xref: /linux/drivers/dma/ppc4xx/adma.c (revision c0e297dc61f8d4453e07afbea1fa8d0e67cd4a34)
1 /*
2  * Copyright (C) 2006-2009 DENX Software Engineering.
3  *
4  * Author: Yuri Tikhonov <yur@emcraft.com>
5  *
6  * Further porting to arch/powerpc by
7  * 	Anatolij Gustschin <agust@denx.de>
8  *
9  * This program is free software; you can redistribute it and/or modify it
10  * under the terms of the GNU General Public License as published by the Free
11  * Software Foundation; either version 2 of the License, or (at your option)
12  * any later version.
13  *
14  * This program is distributed in the hope that it will be useful, but WITHOUT
15  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
16  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
17  * more details.
18  *
19  * The full GNU General Public License is included in this distribution in the
20  * file called COPYING.
21  */
22 
23 /*
24  * This driver supports the asynchrounous DMA copy and RAID engines available
25  * on the AMCC PPC440SPe Processors.
26  * Based on the Intel Xscale(R) family of I/O Processors (IOP 32x, 33x, 134x)
27  * ADMA driver written by D.Williams.
28  */
29 
30 #include <linux/init.h>
31 #include <linux/module.h>
32 #include <linux/async_tx.h>
33 #include <linux/delay.h>
34 #include <linux/dma-mapping.h>
35 #include <linux/spinlock.h>
36 #include <linux/interrupt.h>
37 #include <linux/slab.h>
38 #include <linux/uaccess.h>
39 #include <linux/proc_fs.h>
40 #include <linux/of.h>
41 #include <linux/of_address.h>
42 #include <linux/of_irq.h>
43 #include <linux/of_platform.h>
44 #include <asm/dcr.h>
45 #include <asm/dcr-regs.h>
46 #include "adma.h"
47 #include "../dmaengine.h"
48 
49 enum ppc_adma_init_code {
50 	PPC_ADMA_INIT_OK = 0,
51 	PPC_ADMA_INIT_MEMRES,
52 	PPC_ADMA_INIT_MEMREG,
53 	PPC_ADMA_INIT_ALLOC,
54 	PPC_ADMA_INIT_COHERENT,
55 	PPC_ADMA_INIT_CHANNEL,
56 	PPC_ADMA_INIT_IRQ1,
57 	PPC_ADMA_INIT_IRQ2,
58 	PPC_ADMA_INIT_REGISTER
59 };
60 
61 static char *ppc_adma_errors[] = {
62 	[PPC_ADMA_INIT_OK] = "ok",
63 	[PPC_ADMA_INIT_MEMRES] = "failed to get memory resource",
64 	[PPC_ADMA_INIT_MEMREG] = "failed to request memory region",
65 	[PPC_ADMA_INIT_ALLOC] = "failed to allocate memory for adev "
66 				"structure",
67 	[PPC_ADMA_INIT_COHERENT] = "failed to allocate coherent memory for "
68 				   "hardware descriptors",
69 	[PPC_ADMA_INIT_CHANNEL] = "failed to allocate memory for channel",
70 	[PPC_ADMA_INIT_IRQ1] = "failed to request first irq",
71 	[PPC_ADMA_INIT_IRQ2] = "failed to request second irq",
72 	[PPC_ADMA_INIT_REGISTER] = "failed to register dma async device",
73 };
74 
75 static enum ppc_adma_init_code
76 ppc440spe_adma_devices[PPC440SPE_ADMA_ENGINES_NUM];
77 
78 struct ppc_dma_chan_ref {
79 	struct dma_chan *chan;
80 	struct list_head node;
81 };
82 
83 /* The list of channels exported by ppc440spe ADMA */
84 struct list_head
85 ppc440spe_adma_chan_list = LIST_HEAD_INIT(ppc440spe_adma_chan_list);
86 
87 /* This flag is set when want to refetch the xor chain in the interrupt
88  * handler
89  */
90 static u32 do_xor_refetch;
91 
92 /* Pointer to DMA0, DMA1 CP/CS FIFO */
93 static void *ppc440spe_dma_fifo_buf;
94 
95 /* Pointers to last submitted to DMA0, DMA1 CDBs */
96 static struct ppc440spe_adma_desc_slot *chan_last_sub[3];
97 static struct ppc440spe_adma_desc_slot *chan_first_cdb[3];
98 
99 /* Pointer to last linked and submitted xor CB */
100 static struct ppc440spe_adma_desc_slot *xor_last_linked;
101 static struct ppc440spe_adma_desc_slot *xor_last_submit;
102 
103 /* This array is used in data-check operations for storing a pattern */
104 static char ppc440spe_qword[16];
105 
106 static atomic_t ppc440spe_adma_err_irq_ref;
107 static dcr_host_t ppc440spe_mq_dcr_host;
108 static unsigned int ppc440spe_mq_dcr_len;
109 
110 /* Since RXOR operations use the common register (MQ0_CF2H) for setting-up
111  * the block size in transactions, then we do not allow to activate more than
112  * only one RXOR transactions simultaneously. So use this var to store
113  * the information about is RXOR currently active (PPC440SPE_RXOR_RUN bit is
114  * set) or not (PPC440SPE_RXOR_RUN is clear).
115  */
116 static unsigned long ppc440spe_rxor_state;
117 
118 /* These are used in enable & check routines
119  */
120 static u32 ppc440spe_r6_enabled;
121 static struct ppc440spe_adma_chan *ppc440spe_r6_tchan;
122 static struct completion ppc440spe_r6_test_comp;
123 
124 static int ppc440spe_adma_dma2rxor_prep_src(
125 		struct ppc440spe_adma_desc_slot *desc,
126 		struct ppc440spe_rxor *cursor, int index,
127 		int src_cnt, u32 addr);
128 static void ppc440spe_adma_dma2rxor_set_src(
129 		struct ppc440spe_adma_desc_slot *desc,
130 		int index, dma_addr_t addr);
131 static void ppc440spe_adma_dma2rxor_set_mult(
132 		struct ppc440spe_adma_desc_slot *desc,
133 		int index, u8 mult);
134 
135 #ifdef ADMA_LL_DEBUG
136 #define ADMA_LL_DBG(x) ({ if (1) x; 0; })
137 #else
138 #define ADMA_LL_DBG(x) ({ if (0) x; 0; })
139 #endif
140 
141 static void print_cb(struct ppc440spe_adma_chan *chan, void *block)
142 {
143 	struct dma_cdb *cdb;
144 	struct xor_cb *cb;
145 	int i;
146 
147 	switch (chan->device->id) {
148 	case 0:
149 	case 1:
150 		cdb = block;
151 
152 		pr_debug("CDB at %p [%d]:\n"
153 			"\t attr 0x%02x opc 0x%02x cnt 0x%08x\n"
154 			"\t sg1u 0x%08x sg1l 0x%08x\n"
155 			"\t sg2u 0x%08x sg2l 0x%08x\n"
156 			"\t sg3u 0x%08x sg3l 0x%08x\n",
157 			cdb, chan->device->id,
158 			cdb->attr, cdb->opc, le32_to_cpu(cdb->cnt),
159 			le32_to_cpu(cdb->sg1u), le32_to_cpu(cdb->sg1l),
160 			le32_to_cpu(cdb->sg2u), le32_to_cpu(cdb->sg2l),
161 			le32_to_cpu(cdb->sg3u), le32_to_cpu(cdb->sg3l)
162 		);
163 		break;
164 	case 2:
165 		cb = block;
166 
167 		pr_debug("CB at %p [%d]:\n"
168 			"\t cbc 0x%08x cbbc 0x%08x cbs 0x%08x\n"
169 			"\t cbtah 0x%08x cbtal 0x%08x\n"
170 			"\t cblah 0x%08x cblal 0x%08x\n",
171 			cb, chan->device->id,
172 			cb->cbc, cb->cbbc, cb->cbs,
173 			cb->cbtah, cb->cbtal,
174 			cb->cblah, cb->cblal);
175 		for (i = 0; i < 16; i++) {
176 			if (i && !cb->ops[i].h && !cb->ops[i].l)
177 				continue;
178 			pr_debug("\t ops[%2d]: h 0x%08x l 0x%08x\n",
179 				i, cb->ops[i].h, cb->ops[i].l);
180 		}
181 		break;
182 	}
183 }
184 
185 static void print_cb_list(struct ppc440spe_adma_chan *chan,
186 			  struct ppc440spe_adma_desc_slot *iter)
187 {
188 	for (; iter; iter = iter->hw_next)
189 		print_cb(chan, iter->hw_desc);
190 }
191 
192 static void prep_dma_xor_dbg(int id, dma_addr_t dst, dma_addr_t *src,
193 			     unsigned int src_cnt)
194 {
195 	int i;
196 
197 	pr_debug("\n%s(%d):\nsrc: ", __func__, id);
198 	for (i = 0; i < src_cnt; i++)
199 		pr_debug("\t0x%016llx ", src[i]);
200 	pr_debug("dst:\n\t0x%016llx\n", dst);
201 }
202 
203 static void prep_dma_pq_dbg(int id, dma_addr_t *dst, dma_addr_t *src,
204 			    unsigned int src_cnt)
205 {
206 	int i;
207 
208 	pr_debug("\n%s(%d):\nsrc: ", __func__, id);
209 	for (i = 0; i < src_cnt; i++)
210 		pr_debug("\t0x%016llx ", src[i]);
211 	pr_debug("dst: ");
212 	for (i = 0; i < 2; i++)
213 		pr_debug("\t0x%016llx ", dst[i]);
214 }
215 
216 static void prep_dma_pqzero_sum_dbg(int id, dma_addr_t *src,
217 				    unsigned int src_cnt,
218 				    const unsigned char *scf)
219 {
220 	int i;
221 
222 	pr_debug("\n%s(%d):\nsrc(coef): ", __func__, id);
223 	if (scf) {
224 		for (i = 0; i < src_cnt; i++)
225 			pr_debug("\t0x%016llx(0x%02x) ", src[i], scf[i]);
226 	} else {
227 		for (i = 0; i < src_cnt; i++)
228 			pr_debug("\t0x%016llx(no) ", src[i]);
229 	}
230 
231 	pr_debug("dst: ");
232 	for (i = 0; i < 2; i++)
233 		pr_debug("\t0x%016llx ", src[src_cnt + i]);
234 }
235 
236 /******************************************************************************
237  * Command (Descriptor) Blocks low-level routines
238  ******************************************************************************/
239 /**
240  * ppc440spe_desc_init_interrupt - initialize the descriptor for INTERRUPT
241  * pseudo operation
242  */
243 static void ppc440spe_desc_init_interrupt(struct ppc440spe_adma_desc_slot *desc,
244 					  struct ppc440spe_adma_chan *chan)
245 {
246 	struct xor_cb *p;
247 
248 	switch (chan->device->id) {
249 	case PPC440SPE_XOR_ID:
250 		p = desc->hw_desc;
251 		memset(desc->hw_desc, 0, sizeof(struct xor_cb));
252 		/* NOP with Command Block Complete Enable */
253 		p->cbc = XOR_CBCR_CBCE_BIT;
254 		break;
255 	case PPC440SPE_DMA0_ID:
256 	case PPC440SPE_DMA1_ID:
257 		memset(desc->hw_desc, 0, sizeof(struct dma_cdb));
258 		/* NOP with interrupt */
259 		set_bit(PPC440SPE_DESC_INT, &desc->flags);
260 		break;
261 	default:
262 		printk(KERN_ERR "Unsupported id %d in %s\n", chan->device->id,
263 				__func__);
264 		break;
265 	}
266 }
267 
268 /**
269  * ppc440spe_desc_init_null_xor - initialize the descriptor for NULL XOR
270  * pseudo operation
271  */
272 static void ppc440spe_desc_init_null_xor(struct ppc440spe_adma_desc_slot *desc)
273 {
274 	memset(desc->hw_desc, 0, sizeof(struct xor_cb));
275 	desc->hw_next = NULL;
276 	desc->src_cnt = 0;
277 	desc->dst_cnt = 1;
278 }
279 
280 /**
281  * ppc440spe_desc_init_xor - initialize the descriptor for XOR operation
282  */
283 static void ppc440spe_desc_init_xor(struct ppc440spe_adma_desc_slot *desc,
284 					 int src_cnt, unsigned long flags)
285 {
286 	struct xor_cb *hw_desc = desc->hw_desc;
287 
288 	memset(desc->hw_desc, 0, sizeof(struct xor_cb));
289 	desc->hw_next = NULL;
290 	desc->src_cnt = src_cnt;
291 	desc->dst_cnt = 1;
292 
293 	hw_desc->cbc = XOR_CBCR_TGT_BIT | src_cnt;
294 	if (flags & DMA_PREP_INTERRUPT)
295 		/* Enable interrupt on completion */
296 		hw_desc->cbc |= XOR_CBCR_CBCE_BIT;
297 }
298 
299 /**
300  * ppc440spe_desc_init_dma2pq - initialize the descriptor for PQ
301  * operation in DMA2 controller
302  */
303 static void ppc440spe_desc_init_dma2pq(struct ppc440spe_adma_desc_slot *desc,
304 		int dst_cnt, int src_cnt, unsigned long flags)
305 {
306 	struct xor_cb *hw_desc = desc->hw_desc;
307 
308 	memset(desc->hw_desc, 0, sizeof(struct xor_cb));
309 	desc->hw_next = NULL;
310 	desc->src_cnt = src_cnt;
311 	desc->dst_cnt = dst_cnt;
312 	memset(desc->reverse_flags, 0, sizeof(desc->reverse_flags));
313 	desc->descs_per_op = 0;
314 
315 	hw_desc->cbc = XOR_CBCR_TGT_BIT;
316 	if (flags & DMA_PREP_INTERRUPT)
317 		/* Enable interrupt on completion */
318 		hw_desc->cbc |= XOR_CBCR_CBCE_BIT;
319 }
320 
321 #define DMA_CTRL_FLAGS_LAST	DMA_PREP_FENCE
322 #define DMA_PREP_ZERO_P		(DMA_CTRL_FLAGS_LAST << 1)
323 #define DMA_PREP_ZERO_Q		(DMA_PREP_ZERO_P << 1)
324 
325 /**
326  * ppc440spe_desc_init_dma01pq - initialize the descriptors for PQ operation
327  * with DMA0/1
328  */
329 static void ppc440spe_desc_init_dma01pq(struct ppc440spe_adma_desc_slot *desc,
330 				int dst_cnt, int src_cnt, unsigned long flags,
331 				unsigned long op)
332 {
333 	struct dma_cdb *hw_desc;
334 	struct ppc440spe_adma_desc_slot *iter;
335 	u8 dopc;
336 
337 	/* Common initialization of a PQ descriptors chain */
338 	set_bits(op, &desc->flags);
339 	desc->src_cnt = src_cnt;
340 	desc->dst_cnt = dst_cnt;
341 
342 	/* WXOR MULTICAST if both P and Q are being computed
343 	 * MV_SG1_SG2 if Q only
344 	 */
345 	dopc = (desc->dst_cnt == DMA_DEST_MAX_NUM) ?
346 		DMA_CDB_OPC_MULTICAST : DMA_CDB_OPC_MV_SG1_SG2;
347 
348 	list_for_each_entry(iter, &desc->group_list, chain_node) {
349 		hw_desc = iter->hw_desc;
350 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
351 
352 		if (likely(!list_is_last(&iter->chain_node,
353 				&desc->group_list))) {
354 			/* set 'next' pointer */
355 			iter->hw_next = list_entry(iter->chain_node.next,
356 				struct ppc440spe_adma_desc_slot, chain_node);
357 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
358 		} else {
359 			/* this is the last descriptor.
360 			 * this slot will be pasted from ADMA level
361 			 * each time it wants to configure parameters
362 			 * of the transaction (src, dst, ...)
363 			 */
364 			iter->hw_next = NULL;
365 			if (flags & DMA_PREP_INTERRUPT)
366 				set_bit(PPC440SPE_DESC_INT, &iter->flags);
367 			else
368 				clear_bit(PPC440SPE_DESC_INT, &iter->flags);
369 		}
370 	}
371 
372 	/* Set OPS depending on WXOR/RXOR type of operation */
373 	if (!test_bit(PPC440SPE_DESC_RXOR, &desc->flags)) {
374 		/* This is a WXOR only chain:
375 		 * - first descriptors are for zeroing destinations
376 		 *   if PPC440SPE_ZERO_P/Q set;
377 		 * - descriptors remained are for GF-XOR operations.
378 		 */
379 		iter = list_first_entry(&desc->group_list,
380 					struct ppc440spe_adma_desc_slot,
381 					chain_node);
382 
383 		if (test_bit(PPC440SPE_ZERO_P, &desc->flags)) {
384 			hw_desc = iter->hw_desc;
385 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
386 			iter = list_first_entry(&iter->chain_node,
387 					struct ppc440spe_adma_desc_slot,
388 					chain_node);
389 		}
390 
391 		if (test_bit(PPC440SPE_ZERO_Q, &desc->flags)) {
392 			hw_desc = iter->hw_desc;
393 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
394 			iter = list_first_entry(&iter->chain_node,
395 					struct ppc440spe_adma_desc_slot,
396 					chain_node);
397 		}
398 
399 		list_for_each_entry_from(iter, &desc->group_list, chain_node) {
400 			hw_desc = iter->hw_desc;
401 			hw_desc->opc = dopc;
402 		}
403 	} else {
404 		/* This is either RXOR-only or mixed RXOR/WXOR */
405 
406 		/* The first 1 or 2 slots in chain are always RXOR,
407 		 * if need to calculate P & Q, then there are two
408 		 * RXOR slots; if only P or only Q, then there is one
409 		 */
410 		iter = list_first_entry(&desc->group_list,
411 					struct ppc440spe_adma_desc_slot,
412 					chain_node);
413 		hw_desc = iter->hw_desc;
414 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
415 
416 		if (desc->dst_cnt == DMA_DEST_MAX_NUM) {
417 			iter = list_first_entry(&iter->chain_node,
418 						struct ppc440spe_adma_desc_slot,
419 						chain_node);
420 			hw_desc = iter->hw_desc;
421 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
422 		}
423 
424 		/* The remaining descs (if any) are WXORs */
425 		if (test_bit(PPC440SPE_DESC_WXOR, &desc->flags)) {
426 			iter = list_first_entry(&iter->chain_node,
427 						struct ppc440spe_adma_desc_slot,
428 						chain_node);
429 			list_for_each_entry_from(iter, &desc->group_list,
430 						chain_node) {
431 				hw_desc = iter->hw_desc;
432 				hw_desc->opc = dopc;
433 			}
434 		}
435 	}
436 }
437 
438 /**
439  * ppc440spe_desc_init_dma01pqzero_sum - initialize the descriptor
440  * for PQ_ZERO_SUM operation
441  */
442 static void ppc440spe_desc_init_dma01pqzero_sum(
443 				struct ppc440spe_adma_desc_slot *desc,
444 				int dst_cnt, int src_cnt)
445 {
446 	struct dma_cdb *hw_desc;
447 	struct ppc440spe_adma_desc_slot *iter;
448 	int i = 0;
449 	u8 dopc = (dst_cnt == 2) ? DMA_CDB_OPC_MULTICAST :
450 				   DMA_CDB_OPC_MV_SG1_SG2;
451 	/*
452 	 * Initialize starting from 2nd or 3rd descriptor dependent
453 	 * on dst_cnt. First one or two slots are for cloning P
454 	 * and/or Q to chan->pdest and/or chan->qdest as we have
455 	 * to preserve original P/Q.
456 	 */
457 	iter = list_first_entry(&desc->group_list,
458 				struct ppc440spe_adma_desc_slot, chain_node);
459 	iter = list_entry(iter->chain_node.next,
460 			  struct ppc440spe_adma_desc_slot, chain_node);
461 
462 	if (dst_cnt > 1) {
463 		iter = list_entry(iter->chain_node.next,
464 				  struct ppc440spe_adma_desc_slot, chain_node);
465 	}
466 	/* initialize each source descriptor in chain */
467 	list_for_each_entry_from(iter, &desc->group_list, chain_node) {
468 		hw_desc = iter->hw_desc;
469 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
470 		iter->src_cnt = 0;
471 		iter->dst_cnt = 0;
472 
473 		/* This is a ZERO_SUM operation:
474 		 * - <src_cnt> descriptors starting from 2nd or 3rd
475 		 *   descriptor are for GF-XOR operations;
476 		 * - remaining <dst_cnt> descriptors are for checking the result
477 		 */
478 		if (i++ < src_cnt)
479 			/* MV_SG1_SG2 if only Q is being verified
480 			 * MULTICAST if both P and Q are being verified
481 			 */
482 			hw_desc->opc = dopc;
483 		else
484 			/* DMA_CDB_OPC_DCHECK128 operation */
485 			hw_desc->opc = DMA_CDB_OPC_DCHECK128;
486 
487 		if (likely(!list_is_last(&iter->chain_node,
488 					 &desc->group_list))) {
489 			/* set 'next' pointer */
490 			iter->hw_next = list_entry(iter->chain_node.next,
491 						struct ppc440spe_adma_desc_slot,
492 						chain_node);
493 		} else {
494 			/* this is the last descriptor.
495 			 * this slot will be pasted from ADMA level
496 			 * each time it wants to configure parameters
497 			 * of the transaction (src, dst, ...)
498 			 */
499 			iter->hw_next = NULL;
500 			/* always enable interrupt generation since we get
501 			 * the status of pqzero from the handler
502 			 */
503 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
504 		}
505 	}
506 	desc->src_cnt = src_cnt;
507 	desc->dst_cnt = dst_cnt;
508 }
509 
510 /**
511  * ppc440spe_desc_init_memcpy - initialize the descriptor for MEMCPY operation
512  */
513 static void ppc440spe_desc_init_memcpy(struct ppc440spe_adma_desc_slot *desc,
514 					unsigned long flags)
515 {
516 	struct dma_cdb *hw_desc = desc->hw_desc;
517 
518 	memset(desc->hw_desc, 0, sizeof(struct dma_cdb));
519 	desc->hw_next = NULL;
520 	desc->src_cnt = 1;
521 	desc->dst_cnt = 1;
522 
523 	if (flags & DMA_PREP_INTERRUPT)
524 		set_bit(PPC440SPE_DESC_INT, &desc->flags);
525 	else
526 		clear_bit(PPC440SPE_DESC_INT, &desc->flags);
527 
528 	hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
529 }
530 
531 /**
532  * ppc440spe_desc_set_src_addr - set source address into the descriptor
533  */
534 static void ppc440spe_desc_set_src_addr(struct ppc440spe_adma_desc_slot *desc,
535 					struct ppc440spe_adma_chan *chan,
536 					int src_idx, dma_addr_t addrh,
537 					dma_addr_t addrl)
538 {
539 	struct dma_cdb *dma_hw_desc;
540 	struct xor_cb *xor_hw_desc;
541 	phys_addr_t addr64, tmplow, tmphi;
542 
543 	switch (chan->device->id) {
544 	case PPC440SPE_DMA0_ID:
545 	case PPC440SPE_DMA1_ID:
546 		if (!addrh) {
547 			addr64 = addrl;
548 			tmphi = (addr64 >> 32);
549 			tmplow = (addr64 & 0xFFFFFFFF);
550 		} else {
551 			tmphi = addrh;
552 			tmplow = addrl;
553 		}
554 		dma_hw_desc = desc->hw_desc;
555 		dma_hw_desc->sg1l = cpu_to_le32((u32)tmplow);
556 		dma_hw_desc->sg1u |= cpu_to_le32((u32)tmphi);
557 		break;
558 	case PPC440SPE_XOR_ID:
559 		xor_hw_desc = desc->hw_desc;
560 		xor_hw_desc->ops[src_idx].l = addrl;
561 		xor_hw_desc->ops[src_idx].h |= addrh;
562 		break;
563 	}
564 }
565 
566 /**
567  * ppc440spe_desc_set_src_mult - set source address mult into the descriptor
568  */
569 static void ppc440spe_desc_set_src_mult(struct ppc440spe_adma_desc_slot *desc,
570 			struct ppc440spe_adma_chan *chan, u32 mult_index,
571 			int sg_index, unsigned char mult_value)
572 {
573 	struct dma_cdb *dma_hw_desc;
574 	struct xor_cb *xor_hw_desc;
575 	u32 *psgu;
576 
577 	switch (chan->device->id) {
578 	case PPC440SPE_DMA0_ID:
579 	case PPC440SPE_DMA1_ID:
580 		dma_hw_desc = desc->hw_desc;
581 
582 		switch (sg_index) {
583 		/* for RXOR operations set multiplier
584 		 * into source cued address
585 		 */
586 		case DMA_CDB_SG_SRC:
587 			psgu = &dma_hw_desc->sg1u;
588 			break;
589 		/* for WXOR operations set multiplier
590 		 * into destination cued address(es)
591 		 */
592 		case DMA_CDB_SG_DST1:
593 			psgu = &dma_hw_desc->sg2u;
594 			break;
595 		case DMA_CDB_SG_DST2:
596 			psgu = &dma_hw_desc->sg3u;
597 			break;
598 		default:
599 			BUG();
600 		}
601 
602 		*psgu |= cpu_to_le32(mult_value << mult_index);
603 		break;
604 	case PPC440SPE_XOR_ID:
605 		xor_hw_desc = desc->hw_desc;
606 		break;
607 	default:
608 		BUG();
609 	}
610 }
611 
612 /**
613  * ppc440spe_desc_set_dest_addr - set destination address into the descriptor
614  */
615 static void ppc440spe_desc_set_dest_addr(struct ppc440spe_adma_desc_slot *desc,
616 				struct ppc440spe_adma_chan *chan,
617 				dma_addr_t addrh, dma_addr_t addrl,
618 				u32 dst_idx)
619 {
620 	struct dma_cdb *dma_hw_desc;
621 	struct xor_cb *xor_hw_desc;
622 	phys_addr_t addr64, tmphi, tmplow;
623 	u32 *psgu, *psgl;
624 
625 	switch (chan->device->id) {
626 	case PPC440SPE_DMA0_ID:
627 	case PPC440SPE_DMA1_ID:
628 		if (!addrh) {
629 			addr64 = addrl;
630 			tmphi = (addr64 >> 32);
631 			tmplow = (addr64 & 0xFFFFFFFF);
632 		} else {
633 			tmphi = addrh;
634 			tmplow = addrl;
635 		}
636 		dma_hw_desc = desc->hw_desc;
637 
638 		psgu = dst_idx ? &dma_hw_desc->sg3u : &dma_hw_desc->sg2u;
639 		psgl = dst_idx ? &dma_hw_desc->sg3l : &dma_hw_desc->sg2l;
640 
641 		*psgl = cpu_to_le32((u32)tmplow);
642 		*psgu |= cpu_to_le32((u32)tmphi);
643 		break;
644 	case PPC440SPE_XOR_ID:
645 		xor_hw_desc = desc->hw_desc;
646 		xor_hw_desc->cbtal = addrl;
647 		xor_hw_desc->cbtah |= addrh;
648 		break;
649 	}
650 }
651 
652 /**
653  * ppc440spe_desc_set_byte_count - set number of data bytes involved
654  * into the operation
655  */
656 static void ppc440spe_desc_set_byte_count(struct ppc440spe_adma_desc_slot *desc,
657 				struct ppc440spe_adma_chan *chan,
658 				u32 byte_count)
659 {
660 	struct dma_cdb *dma_hw_desc;
661 	struct xor_cb *xor_hw_desc;
662 
663 	switch (chan->device->id) {
664 	case PPC440SPE_DMA0_ID:
665 	case PPC440SPE_DMA1_ID:
666 		dma_hw_desc = desc->hw_desc;
667 		dma_hw_desc->cnt = cpu_to_le32(byte_count);
668 		break;
669 	case PPC440SPE_XOR_ID:
670 		xor_hw_desc = desc->hw_desc;
671 		xor_hw_desc->cbbc = byte_count;
672 		break;
673 	}
674 }
675 
676 /**
677  * ppc440spe_desc_set_rxor_block_size - set RXOR block size
678  */
679 static inline void ppc440spe_desc_set_rxor_block_size(u32 byte_count)
680 {
681 	/* assume that byte_count is aligned on the 512-boundary;
682 	 * thus write it directly to the register (bits 23:31 are
683 	 * reserved there).
684 	 */
685 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_CF2H, byte_count);
686 }
687 
688 /**
689  * ppc440spe_desc_set_dcheck - set CHECK pattern
690  */
691 static void ppc440spe_desc_set_dcheck(struct ppc440spe_adma_desc_slot *desc,
692 				struct ppc440spe_adma_chan *chan, u8 *qword)
693 {
694 	struct dma_cdb *dma_hw_desc;
695 
696 	switch (chan->device->id) {
697 	case PPC440SPE_DMA0_ID:
698 	case PPC440SPE_DMA1_ID:
699 		dma_hw_desc = desc->hw_desc;
700 		iowrite32(qword[0], &dma_hw_desc->sg3l);
701 		iowrite32(qword[4], &dma_hw_desc->sg3u);
702 		iowrite32(qword[8], &dma_hw_desc->sg2l);
703 		iowrite32(qword[12], &dma_hw_desc->sg2u);
704 		break;
705 	default:
706 		BUG();
707 	}
708 }
709 
710 /**
711  * ppc440spe_xor_set_link - set link address in xor CB
712  */
713 static void ppc440spe_xor_set_link(struct ppc440spe_adma_desc_slot *prev_desc,
714 				struct ppc440spe_adma_desc_slot *next_desc)
715 {
716 	struct xor_cb *xor_hw_desc = prev_desc->hw_desc;
717 
718 	if (unlikely(!next_desc || !(next_desc->phys))) {
719 		printk(KERN_ERR "%s: next_desc=0x%p; next_desc->phys=0x%llx\n",
720 			__func__, next_desc,
721 			next_desc ? next_desc->phys : 0);
722 		BUG();
723 	}
724 
725 	xor_hw_desc->cbs = 0;
726 	xor_hw_desc->cblal = next_desc->phys;
727 	xor_hw_desc->cblah = 0;
728 	xor_hw_desc->cbc |= XOR_CBCR_LNK_BIT;
729 }
730 
731 /**
732  * ppc440spe_desc_set_link - set the address of descriptor following this
733  * descriptor in chain
734  */
735 static void ppc440spe_desc_set_link(struct ppc440spe_adma_chan *chan,
736 				struct ppc440spe_adma_desc_slot *prev_desc,
737 				struct ppc440spe_adma_desc_slot *next_desc)
738 {
739 	unsigned long flags;
740 	struct ppc440spe_adma_desc_slot *tail = next_desc;
741 
742 	if (unlikely(!prev_desc || !next_desc ||
743 		(prev_desc->hw_next && prev_desc->hw_next != next_desc))) {
744 		/* If previous next is overwritten something is wrong.
745 		 * though we may refetch from append to initiate list
746 		 * processing; in this case - it's ok.
747 		 */
748 		printk(KERN_ERR "%s: prev_desc=0x%p; next_desc=0x%p; "
749 			"prev->hw_next=0x%p\n", __func__, prev_desc,
750 			next_desc, prev_desc ? prev_desc->hw_next : 0);
751 		BUG();
752 	}
753 
754 	local_irq_save(flags);
755 
756 	/* do s/w chaining both for DMA and XOR descriptors */
757 	prev_desc->hw_next = next_desc;
758 
759 	switch (chan->device->id) {
760 	case PPC440SPE_DMA0_ID:
761 	case PPC440SPE_DMA1_ID:
762 		break;
763 	case PPC440SPE_XOR_ID:
764 		/* bind descriptor to the chain */
765 		while (tail->hw_next)
766 			tail = tail->hw_next;
767 		xor_last_linked = tail;
768 
769 		if (prev_desc == xor_last_submit)
770 			/* do not link to the last submitted CB */
771 			break;
772 		ppc440spe_xor_set_link(prev_desc, next_desc);
773 		break;
774 	}
775 
776 	local_irq_restore(flags);
777 }
778 
779 /**
780  * ppc440spe_desc_get_link - get the address of the descriptor that
781  * follows this one
782  */
783 static inline u32 ppc440spe_desc_get_link(struct ppc440spe_adma_desc_slot *desc,
784 					struct ppc440spe_adma_chan *chan)
785 {
786 	if (!desc->hw_next)
787 		return 0;
788 
789 	return desc->hw_next->phys;
790 }
791 
792 /**
793  * ppc440spe_desc_is_aligned - check alignment
794  */
795 static inline int ppc440spe_desc_is_aligned(
796 	struct ppc440spe_adma_desc_slot *desc, int num_slots)
797 {
798 	return (desc->idx & (num_slots - 1)) ? 0 : 1;
799 }
800 
801 /**
802  * ppc440spe_chan_xor_slot_count - get the number of slots necessary for
803  * XOR operation
804  */
805 static int ppc440spe_chan_xor_slot_count(size_t len, int src_cnt,
806 			int *slots_per_op)
807 {
808 	int slot_cnt;
809 
810 	/* each XOR descriptor provides up to 16 source operands */
811 	slot_cnt = *slots_per_op = (src_cnt + XOR_MAX_OPS - 1)/XOR_MAX_OPS;
812 
813 	if (likely(len <= PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT))
814 		return slot_cnt;
815 
816 	printk(KERN_ERR "%s: len %d > max %d !!\n",
817 		__func__, len, PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT);
818 	BUG();
819 	return slot_cnt;
820 }
821 
822 /**
823  * ppc440spe_dma2_pq_slot_count - get the number of slots necessary for
824  * DMA2 PQ operation
825  */
826 static int ppc440spe_dma2_pq_slot_count(dma_addr_t *srcs,
827 		int src_cnt, size_t len)
828 {
829 	signed long long order = 0;
830 	int state = 0;
831 	int addr_count = 0;
832 	int i;
833 	for (i = 1; i < src_cnt; i++) {
834 		dma_addr_t cur_addr = srcs[i];
835 		dma_addr_t old_addr = srcs[i-1];
836 		switch (state) {
837 		case 0:
838 			if (cur_addr == old_addr + len) {
839 				/* direct RXOR */
840 				order = 1;
841 				state = 1;
842 				if (i == src_cnt-1)
843 					addr_count++;
844 			} else if (old_addr == cur_addr + len) {
845 				/* reverse RXOR */
846 				order = -1;
847 				state = 1;
848 				if (i == src_cnt-1)
849 					addr_count++;
850 			} else {
851 				state = 3;
852 			}
853 			break;
854 		case 1:
855 			if (i == src_cnt-2 || (order == -1
856 				&& cur_addr != old_addr - len)) {
857 				order = 0;
858 				state = 0;
859 				addr_count++;
860 			} else if (cur_addr == old_addr + len*order) {
861 				state = 2;
862 				if (i == src_cnt-1)
863 					addr_count++;
864 			} else if (cur_addr == old_addr + 2*len) {
865 				state = 2;
866 				if (i == src_cnt-1)
867 					addr_count++;
868 			} else if (cur_addr == old_addr + 3*len) {
869 				state = 2;
870 				if (i == src_cnt-1)
871 					addr_count++;
872 			} else {
873 				order = 0;
874 				state = 0;
875 				addr_count++;
876 			}
877 			break;
878 		case 2:
879 			order = 0;
880 			state = 0;
881 			addr_count++;
882 				break;
883 		}
884 		if (state == 3)
885 			break;
886 	}
887 	if (src_cnt <= 1 || (state != 1 && state != 2)) {
888 		pr_err("%s: src_cnt=%d, state=%d, addr_count=%d, order=%lld\n",
889 			__func__, src_cnt, state, addr_count, order);
890 		for (i = 0; i < src_cnt; i++)
891 			pr_err("\t[%d] 0x%llx \n", i, srcs[i]);
892 		BUG();
893 	}
894 
895 	return (addr_count + XOR_MAX_OPS - 1) / XOR_MAX_OPS;
896 }
897 
898 
899 /******************************************************************************
900  * ADMA channel low-level routines
901  ******************************************************************************/
902 
903 static u32
904 ppc440spe_chan_get_current_descriptor(struct ppc440spe_adma_chan *chan);
905 static void ppc440spe_chan_append(struct ppc440spe_adma_chan *chan);
906 
907 /**
908  * ppc440spe_adma_device_clear_eot_status - interrupt ack to XOR or DMA engine
909  */
910 static void ppc440spe_adma_device_clear_eot_status(
911 					struct ppc440spe_adma_chan *chan)
912 {
913 	struct dma_regs *dma_reg;
914 	struct xor_regs *xor_reg;
915 	u8 *p = chan->device->dma_desc_pool_virt;
916 	struct dma_cdb *cdb;
917 	u32 rv, i;
918 
919 	switch (chan->device->id) {
920 	case PPC440SPE_DMA0_ID:
921 	case PPC440SPE_DMA1_ID:
922 		/* read FIFO to ack */
923 		dma_reg = chan->device->dma_reg;
924 		while ((rv = ioread32(&dma_reg->csfpl))) {
925 			i = rv & DMA_CDB_ADDR_MSK;
926 			cdb = (struct dma_cdb *)&p[i -
927 			    (u32)chan->device->dma_desc_pool];
928 
929 			/* Clear opcode to ack. This is necessary for
930 			 * ZeroSum operations only
931 			 */
932 			cdb->opc = 0;
933 
934 			if (test_bit(PPC440SPE_RXOR_RUN,
935 			    &ppc440spe_rxor_state)) {
936 				/* probably this is a completed RXOR op,
937 				 * get pointer to CDB using the fact that
938 				 * physical and virtual addresses of CDB
939 				 * in pools have the same offsets
940 				 */
941 				if (le32_to_cpu(cdb->sg1u) &
942 				    DMA_CUED_XOR_BASE) {
943 					/* this is a RXOR */
944 					clear_bit(PPC440SPE_RXOR_RUN,
945 						  &ppc440spe_rxor_state);
946 				}
947 			}
948 
949 			if (rv & DMA_CDB_STATUS_MSK) {
950 				/* ZeroSum check failed
951 				 */
952 				struct ppc440spe_adma_desc_slot *iter;
953 				dma_addr_t phys = rv & ~DMA_CDB_MSK;
954 
955 				/*
956 				 * Update the status of corresponding
957 				 * descriptor.
958 				 */
959 				list_for_each_entry(iter, &chan->chain,
960 				    chain_node) {
961 					if (iter->phys == phys)
962 						break;
963 				}
964 				/*
965 				 * if cannot find the corresponding
966 				 * slot it's a bug
967 				 */
968 				BUG_ON(&iter->chain_node == &chan->chain);
969 
970 				if (iter->xor_check_result) {
971 					if (test_bit(PPC440SPE_DESC_PCHECK,
972 						     &iter->flags)) {
973 						*iter->xor_check_result |=
974 							SUM_CHECK_P_RESULT;
975 					} else
976 					if (test_bit(PPC440SPE_DESC_QCHECK,
977 						     &iter->flags)) {
978 						*iter->xor_check_result |=
979 							SUM_CHECK_Q_RESULT;
980 					} else
981 						BUG();
982 				}
983 			}
984 		}
985 
986 		rv = ioread32(&dma_reg->dsts);
987 		if (rv) {
988 			pr_err("DMA%d err status: 0x%x\n",
989 			       chan->device->id, rv);
990 			/* write back to clear */
991 			iowrite32(rv, &dma_reg->dsts);
992 		}
993 		break;
994 	case PPC440SPE_XOR_ID:
995 		/* reset status bits to ack */
996 		xor_reg = chan->device->xor_reg;
997 		rv = ioread32be(&xor_reg->sr);
998 		iowrite32be(rv, &xor_reg->sr);
999 
1000 		if (rv & (XOR_IE_ICBIE_BIT|XOR_IE_ICIE_BIT|XOR_IE_RPTIE_BIT)) {
1001 			if (rv & XOR_IE_RPTIE_BIT) {
1002 				/* Read PLB Timeout Error.
1003 				 * Try to resubmit the CB
1004 				 */
1005 				u32 val = ioread32be(&xor_reg->ccbalr);
1006 
1007 				iowrite32be(val, &xor_reg->cblalr);
1008 
1009 				val = ioread32be(&xor_reg->crsr);
1010 				iowrite32be(val | XOR_CRSR_XAE_BIT,
1011 					    &xor_reg->crsr);
1012 			} else
1013 				pr_err("XOR ERR 0x%x status\n", rv);
1014 			break;
1015 		}
1016 
1017 		/*  if the XORcore is idle, but there are unprocessed CBs
1018 		 * then refetch the s/w chain here
1019 		 */
1020 		if (!(ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT) &&
1021 		    do_xor_refetch)
1022 			ppc440spe_chan_append(chan);
1023 		break;
1024 	}
1025 }
1026 
1027 /**
1028  * ppc440spe_chan_is_busy - get the channel status
1029  */
1030 static int ppc440spe_chan_is_busy(struct ppc440spe_adma_chan *chan)
1031 {
1032 	struct dma_regs *dma_reg;
1033 	struct xor_regs *xor_reg;
1034 	int busy = 0;
1035 
1036 	switch (chan->device->id) {
1037 	case PPC440SPE_DMA0_ID:
1038 	case PPC440SPE_DMA1_ID:
1039 		dma_reg = chan->device->dma_reg;
1040 		/*  if command FIFO's head and tail pointers are equal and
1041 		 * status tail is the same as command, then channel is free
1042 		 */
1043 		if (ioread16(&dma_reg->cpfhp) != ioread16(&dma_reg->cpftp) ||
1044 		    ioread16(&dma_reg->cpftp) != ioread16(&dma_reg->csftp))
1045 			busy = 1;
1046 		break;
1047 	case PPC440SPE_XOR_ID:
1048 		/* use the special status bit for the XORcore
1049 		 */
1050 		xor_reg = chan->device->xor_reg;
1051 		busy = (ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT) ? 1 : 0;
1052 		break;
1053 	}
1054 
1055 	return busy;
1056 }
1057 
1058 /**
1059  * ppc440spe_chan_set_first_xor_descriptor -  init XORcore chain
1060  */
1061 static void ppc440spe_chan_set_first_xor_descriptor(
1062 				struct ppc440spe_adma_chan *chan,
1063 				struct ppc440spe_adma_desc_slot *next_desc)
1064 {
1065 	struct xor_regs *xor_reg = chan->device->xor_reg;
1066 
1067 	if (ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT)
1068 		printk(KERN_INFO "%s: Warn: XORcore is running "
1069 			"when try to set the first CDB!\n",
1070 			__func__);
1071 
1072 	xor_last_submit = xor_last_linked = next_desc;
1073 
1074 	iowrite32be(XOR_CRSR_64BA_BIT, &xor_reg->crsr);
1075 
1076 	iowrite32be(next_desc->phys, &xor_reg->cblalr);
1077 	iowrite32be(0, &xor_reg->cblahr);
1078 	iowrite32be(ioread32be(&xor_reg->cbcr) | XOR_CBCR_LNK_BIT,
1079 		    &xor_reg->cbcr);
1080 
1081 	chan->hw_chain_inited = 1;
1082 }
1083 
1084 /**
1085  * ppc440spe_dma_put_desc - put DMA0,1 descriptor to FIFO.
1086  * called with irqs disabled
1087  */
1088 static void ppc440spe_dma_put_desc(struct ppc440spe_adma_chan *chan,
1089 		struct ppc440spe_adma_desc_slot *desc)
1090 {
1091 	u32 pcdb;
1092 	struct dma_regs *dma_reg = chan->device->dma_reg;
1093 
1094 	pcdb = desc->phys;
1095 	if (!test_bit(PPC440SPE_DESC_INT, &desc->flags))
1096 		pcdb |= DMA_CDB_NO_INT;
1097 
1098 	chan_last_sub[chan->device->id] = desc;
1099 
1100 	ADMA_LL_DBG(print_cb(chan, desc->hw_desc));
1101 
1102 	iowrite32(pcdb, &dma_reg->cpfpl);
1103 }
1104 
1105 /**
1106  * ppc440spe_chan_append - update the h/w chain in the channel
1107  */
1108 static void ppc440spe_chan_append(struct ppc440spe_adma_chan *chan)
1109 {
1110 	struct xor_regs *xor_reg;
1111 	struct ppc440spe_adma_desc_slot *iter;
1112 	struct xor_cb *xcb;
1113 	u32 cur_desc;
1114 	unsigned long flags;
1115 
1116 	local_irq_save(flags);
1117 
1118 	switch (chan->device->id) {
1119 	case PPC440SPE_DMA0_ID:
1120 	case PPC440SPE_DMA1_ID:
1121 		cur_desc = ppc440spe_chan_get_current_descriptor(chan);
1122 
1123 		if (likely(cur_desc)) {
1124 			iter = chan_last_sub[chan->device->id];
1125 			BUG_ON(!iter);
1126 		} else {
1127 			/* first peer */
1128 			iter = chan_first_cdb[chan->device->id];
1129 			BUG_ON(!iter);
1130 			ppc440spe_dma_put_desc(chan, iter);
1131 			chan->hw_chain_inited = 1;
1132 		}
1133 
1134 		/* is there something new to append */
1135 		if (!iter->hw_next)
1136 			break;
1137 
1138 		/* flush descriptors from the s/w queue to fifo */
1139 		list_for_each_entry_continue(iter, &chan->chain, chain_node) {
1140 			ppc440spe_dma_put_desc(chan, iter);
1141 			if (!iter->hw_next)
1142 				break;
1143 		}
1144 		break;
1145 	case PPC440SPE_XOR_ID:
1146 		/* update h/w links and refetch */
1147 		if (!xor_last_submit->hw_next)
1148 			break;
1149 
1150 		xor_reg = chan->device->xor_reg;
1151 		/* the last linked CDB has to generate an interrupt
1152 		 * that we'd be able to append the next lists to h/w
1153 		 * regardless of the XOR engine state at the moment of
1154 		 * appending of these next lists
1155 		 */
1156 		xcb = xor_last_linked->hw_desc;
1157 		xcb->cbc |= XOR_CBCR_CBCE_BIT;
1158 
1159 		if (!(ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT)) {
1160 			/* XORcore is idle. Refetch now */
1161 			do_xor_refetch = 0;
1162 			ppc440spe_xor_set_link(xor_last_submit,
1163 				xor_last_submit->hw_next);
1164 
1165 			ADMA_LL_DBG(print_cb_list(chan,
1166 				xor_last_submit->hw_next));
1167 
1168 			xor_last_submit = xor_last_linked;
1169 			iowrite32be(ioread32be(&xor_reg->crsr) |
1170 				    XOR_CRSR_RCBE_BIT | XOR_CRSR_64BA_BIT,
1171 				    &xor_reg->crsr);
1172 		} else {
1173 			/* XORcore is running. Refetch later in the handler */
1174 			do_xor_refetch = 1;
1175 		}
1176 
1177 		break;
1178 	}
1179 
1180 	local_irq_restore(flags);
1181 }
1182 
1183 /**
1184  * ppc440spe_chan_get_current_descriptor - get the currently executed descriptor
1185  */
1186 static u32
1187 ppc440spe_chan_get_current_descriptor(struct ppc440spe_adma_chan *chan)
1188 {
1189 	struct dma_regs *dma_reg;
1190 	struct xor_regs *xor_reg;
1191 
1192 	if (unlikely(!chan->hw_chain_inited))
1193 		/* h/w descriptor chain is not initialized yet */
1194 		return 0;
1195 
1196 	switch (chan->device->id) {
1197 	case PPC440SPE_DMA0_ID:
1198 	case PPC440SPE_DMA1_ID:
1199 		dma_reg = chan->device->dma_reg;
1200 		return ioread32(&dma_reg->acpl) & (~DMA_CDB_MSK);
1201 	case PPC440SPE_XOR_ID:
1202 		xor_reg = chan->device->xor_reg;
1203 		return ioread32be(&xor_reg->ccbalr);
1204 	}
1205 	return 0;
1206 }
1207 
1208 /**
1209  * ppc440spe_chan_run - enable the channel
1210  */
1211 static void ppc440spe_chan_run(struct ppc440spe_adma_chan *chan)
1212 {
1213 	struct xor_regs *xor_reg;
1214 
1215 	switch (chan->device->id) {
1216 	case PPC440SPE_DMA0_ID:
1217 	case PPC440SPE_DMA1_ID:
1218 		/* DMAs are always enabled, do nothing */
1219 		break;
1220 	case PPC440SPE_XOR_ID:
1221 		/* drain write buffer */
1222 		xor_reg = chan->device->xor_reg;
1223 
1224 		/* fetch descriptor pointed to in <link> */
1225 		iowrite32be(XOR_CRSR_64BA_BIT | XOR_CRSR_XAE_BIT,
1226 			    &xor_reg->crsr);
1227 		break;
1228 	}
1229 }
1230 
1231 /******************************************************************************
1232  * ADMA device level
1233  ******************************************************************************/
1234 
1235 static void ppc440spe_chan_start_null_xor(struct ppc440spe_adma_chan *chan);
1236 static int ppc440spe_adma_alloc_chan_resources(struct dma_chan *chan);
1237 
1238 static dma_cookie_t
1239 ppc440spe_adma_tx_submit(struct dma_async_tx_descriptor *tx);
1240 
1241 static void ppc440spe_adma_set_dest(struct ppc440spe_adma_desc_slot *tx,
1242 				    dma_addr_t addr, int index);
1243 static void
1244 ppc440spe_adma_memcpy_xor_set_src(struct ppc440spe_adma_desc_slot *tx,
1245 				  dma_addr_t addr, int index);
1246 
1247 static void
1248 ppc440spe_adma_pq_set_dest(struct ppc440spe_adma_desc_slot *tx,
1249 			   dma_addr_t *paddr, unsigned long flags);
1250 static void
1251 ppc440spe_adma_pq_set_src(struct ppc440spe_adma_desc_slot *tx,
1252 			  dma_addr_t addr, int index);
1253 static void
1254 ppc440spe_adma_pq_set_src_mult(struct ppc440spe_adma_desc_slot *tx,
1255 			       unsigned char mult, int index, int dst_pos);
1256 static void
1257 ppc440spe_adma_pqzero_sum_set_dest(struct ppc440spe_adma_desc_slot *tx,
1258 				   dma_addr_t paddr, dma_addr_t qaddr);
1259 
1260 static struct page *ppc440spe_rxor_srcs[32];
1261 
1262 /**
1263  * ppc440spe_can_rxor - check if the operands may be processed with RXOR
1264  */
1265 static int ppc440spe_can_rxor(struct page **srcs, int src_cnt, size_t len)
1266 {
1267 	int i, order = 0, state = 0;
1268 	int idx = 0;
1269 
1270 	if (unlikely(!(src_cnt > 1)))
1271 		return 0;
1272 
1273 	BUG_ON(src_cnt > ARRAY_SIZE(ppc440spe_rxor_srcs));
1274 
1275 	/* Skip holes in the source list before checking */
1276 	for (i = 0; i < src_cnt; i++) {
1277 		if (!srcs[i])
1278 			continue;
1279 		ppc440spe_rxor_srcs[idx++] = srcs[i];
1280 	}
1281 	src_cnt = idx;
1282 
1283 	for (i = 1; i < src_cnt; i++) {
1284 		char *cur_addr = page_address(ppc440spe_rxor_srcs[i]);
1285 		char *old_addr = page_address(ppc440spe_rxor_srcs[i - 1]);
1286 
1287 		switch (state) {
1288 		case 0:
1289 			if (cur_addr == old_addr + len) {
1290 				/* direct RXOR */
1291 				order = 1;
1292 				state = 1;
1293 			} else if (old_addr == cur_addr + len) {
1294 				/* reverse RXOR */
1295 				order = -1;
1296 				state = 1;
1297 			} else
1298 				goto out;
1299 			break;
1300 		case 1:
1301 			if ((i == src_cnt - 2) ||
1302 			    (order == -1 && cur_addr != old_addr - len)) {
1303 				order = 0;
1304 				state = 0;
1305 			} else if ((cur_addr == old_addr + len * order) ||
1306 				   (cur_addr == old_addr + 2 * len) ||
1307 				   (cur_addr == old_addr + 3 * len)) {
1308 				state = 2;
1309 			} else {
1310 				order = 0;
1311 				state = 0;
1312 			}
1313 			break;
1314 		case 2:
1315 			order = 0;
1316 			state = 0;
1317 			break;
1318 		}
1319 	}
1320 
1321 out:
1322 	if (state == 1 || state == 2)
1323 		return 1;
1324 
1325 	return 0;
1326 }
1327 
1328 /**
1329  * ppc440spe_adma_device_estimate - estimate the efficiency of processing
1330  *	the operation given on this channel. It's assumed that 'chan' is
1331  *	capable to process 'cap' type of operation.
1332  * @chan: channel to use
1333  * @cap: type of transaction
1334  * @dst_lst: array of destination pointers
1335  * @dst_cnt: number of destination operands
1336  * @src_lst: array of source pointers
1337  * @src_cnt: number of source operands
1338  * @src_sz: size of each source operand
1339  */
1340 static int ppc440spe_adma_estimate(struct dma_chan *chan,
1341 	enum dma_transaction_type cap, struct page **dst_lst, int dst_cnt,
1342 	struct page **src_lst, int src_cnt, size_t src_sz)
1343 {
1344 	int ef = 1;
1345 
1346 	if (cap == DMA_PQ || cap == DMA_PQ_VAL) {
1347 		/* If RAID-6 capabilities were not activated don't try
1348 		 * to use them
1349 		 */
1350 		if (unlikely(!ppc440spe_r6_enabled))
1351 			return -1;
1352 	}
1353 	/*  In the current implementation of ppc440spe ADMA driver it
1354 	 * makes sense to pick out only pq case, because it may be
1355 	 * processed:
1356 	 * (1) either using Biskup method on DMA2;
1357 	 * (2) or on DMA0/1.
1358 	 *  Thus we give a favour to (1) if the sources are suitable;
1359 	 * else let it be processed on one of the DMA0/1 engines.
1360 	 *  In the sum_product case where destination is also the
1361 	 * source process it on DMA0/1 only.
1362 	 */
1363 	if (cap == DMA_PQ && chan->chan_id == PPC440SPE_XOR_ID) {
1364 
1365 		if (dst_cnt == 1 && src_cnt == 2 && dst_lst[0] == src_lst[1])
1366 			ef = 0; /* sum_product case, process on DMA0/1 */
1367 		else if (ppc440spe_can_rxor(src_lst, src_cnt, src_sz))
1368 			ef = 3; /* override (DMA0/1 + idle) */
1369 		else
1370 			ef = 0; /* can't process on DMA2 if !rxor */
1371 	}
1372 
1373 	/* channel idleness increases the priority */
1374 	if (likely(ef) &&
1375 	    !ppc440spe_chan_is_busy(to_ppc440spe_adma_chan(chan)))
1376 		ef++;
1377 
1378 	return ef;
1379 }
1380 
1381 struct dma_chan *
1382 ppc440spe_async_tx_find_best_channel(enum dma_transaction_type cap,
1383 	struct page **dst_lst, int dst_cnt, struct page **src_lst,
1384 	int src_cnt, size_t src_sz)
1385 {
1386 	struct dma_chan *best_chan = NULL;
1387 	struct ppc_dma_chan_ref *ref;
1388 	int best_rank = -1;
1389 
1390 	if (unlikely(!src_sz))
1391 		return NULL;
1392 	if (src_sz > PAGE_SIZE) {
1393 		/*
1394 		 * should a user of the api ever pass > PAGE_SIZE requests
1395 		 * we sort out cases where temporary page-sized buffers
1396 		 * are used.
1397 		 */
1398 		switch (cap) {
1399 		case DMA_PQ:
1400 			if (src_cnt == 1 && dst_lst[1] == src_lst[0])
1401 				return NULL;
1402 			if (src_cnt == 2 && dst_lst[1] == src_lst[1])
1403 				return NULL;
1404 			break;
1405 		case DMA_PQ_VAL:
1406 		case DMA_XOR_VAL:
1407 			return NULL;
1408 		default:
1409 			break;
1410 		}
1411 	}
1412 
1413 	list_for_each_entry(ref, &ppc440spe_adma_chan_list, node) {
1414 		if (dma_has_cap(cap, ref->chan->device->cap_mask)) {
1415 			int rank;
1416 
1417 			rank = ppc440spe_adma_estimate(ref->chan, cap, dst_lst,
1418 					dst_cnt, src_lst, src_cnt, src_sz);
1419 			if (rank > best_rank) {
1420 				best_rank = rank;
1421 				best_chan = ref->chan;
1422 			}
1423 		}
1424 	}
1425 
1426 	return best_chan;
1427 }
1428 EXPORT_SYMBOL_GPL(ppc440spe_async_tx_find_best_channel);
1429 
1430 /**
1431  * ppc440spe_get_group_entry - get group entry with index idx
1432  * @tdesc: is the last allocated slot in the group.
1433  */
1434 static struct ppc440spe_adma_desc_slot *
1435 ppc440spe_get_group_entry(struct ppc440spe_adma_desc_slot *tdesc, u32 entry_idx)
1436 {
1437 	struct ppc440spe_adma_desc_slot *iter = tdesc->group_head;
1438 	int i = 0;
1439 
1440 	if (entry_idx < 0 || entry_idx >= (tdesc->src_cnt + tdesc->dst_cnt)) {
1441 		printk("%s: entry_idx %d, src_cnt %d, dst_cnt %d\n",
1442 			__func__, entry_idx, tdesc->src_cnt, tdesc->dst_cnt);
1443 		BUG();
1444 	}
1445 
1446 	list_for_each_entry(iter, &tdesc->group_list, chain_node) {
1447 		if (i++ == entry_idx)
1448 			break;
1449 	}
1450 	return iter;
1451 }
1452 
1453 /**
1454  * ppc440spe_adma_free_slots - flags descriptor slots for reuse
1455  * @slot: Slot to free
1456  * Caller must hold &ppc440spe_chan->lock while calling this function
1457  */
1458 static void ppc440spe_adma_free_slots(struct ppc440spe_adma_desc_slot *slot,
1459 				      struct ppc440spe_adma_chan *chan)
1460 {
1461 	int stride = slot->slots_per_op;
1462 
1463 	while (stride--) {
1464 		slot->slots_per_op = 0;
1465 		slot = list_entry(slot->slot_node.next,
1466 				struct ppc440spe_adma_desc_slot,
1467 				slot_node);
1468 	}
1469 }
1470 
1471 /**
1472  * ppc440spe_adma_run_tx_complete_actions - call functions to be called
1473  * upon completion
1474  */
1475 static dma_cookie_t ppc440spe_adma_run_tx_complete_actions(
1476 		struct ppc440spe_adma_desc_slot *desc,
1477 		struct ppc440spe_adma_chan *chan,
1478 		dma_cookie_t cookie)
1479 {
1480 	BUG_ON(desc->async_tx.cookie < 0);
1481 	if (desc->async_tx.cookie > 0) {
1482 		cookie = desc->async_tx.cookie;
1483 		desc->async_tx.cookie = 0;
1484 
1485 		/* call the callback (must not sleep or submit new
1486 		 * operations to this channel)
1487 		 */
1488 		if (desc->async_tx.callback)
1489 			desc->async_tx.callback(
1490 				desc->async_tx.callback_param);
1491 
1492 		dma_descriptor_unmap(&desc->async_tx);
1493 	}
1494 
1495 	/* run dependent operations */
1496 	dma_run_dependencies(&desc->async_tx);
1497 
1498 	return cookie;
1499 }
1500 
1501 /**
1502  * ppc440spe_adma_clean_slot - clean up CDB slot (if ack is set)
1503  */
1504 static int ppc440spe_adma_clean_slot(struct ppc440spe_adma_desc_slot *desc,
1505 		struct ppc440spe_adma_chan *chan)
1506 {
1507 	/* the client is allowed to attach dependent operations
1508 	 * until 'ack' is set
1509 	 */
1510 	if (!async_tx_test_ack(&desc->async_tx))
1511 		return 0;
1512 
1513 	/* leave the last descriptor in the chain
1514 	 * so we can append to it
1515 	 */
1516 	if (list_is_last(&desc->chain_node, &chan->chain) ||
1517 	    desc->phys == ppc440spe_chan_get_current_descriptor(chan))
1518 		return 1;
1519 
1520 	if (chan->device->id != PPC440SPE_XOR_ID) {
1521 		/* our DMA interrupt handler clears opc field of
1522 		 * each processed descriptor. For all types of
1523 		 * operations except for ZeroSum we do not actually
1524 		 * need ack from the interrupt handler. ZeroSum is a
1525 		 * special case since the result of this operation
1526 		 * is available from the handler only, so if we see
1527 		 * such type of descriptor (which is unprocessed yet)
1528 		 * then leave it in chain.
1529 		 */
1530 		struct dma_cdb *cdb = desc->hw_desc;
1531 		if (cdb->opc == DMA_CDB_OPC_DCHECK128)
1532 			return 1;
1533 	}
1534 
1535 	dev_dbg(chan->device->common.dev, "\tfree slot %llx: %d stride: %d\n",
1536 		desc->phys, desc->idx, desc->slots_per_op);
1537 
1538 	list_del(&desc->chain_node);
1539 	ppc440spe_adma_free_slots(desc, chan);
1540 	return 0;
1541 }
1542 
1543 /**
1544  * __ppc440spe_adma_slot_cleanup - this is the common clean-up routine
1545  *	which runs through the channel CDBs list until reach the descriptor
1546  *	currently processed. When routine determines that all CDBs of group
1547  *	are completed then corresponding callbacks (if any) are called and slots
1548  *	are freed.
1549  */
1550 static void __ppc440spe_adma_slot_cleanup(struct ppc440spe_adma_chan *chan)
1551 {
1552 	struct ppc440spe_adma_desc_slot *iter, *_iter, *group_start = NULL;
1553 	dma_cookie_t cookie = 0;
1554 	u32 current_desc = ppc440spe_chan_get_current_descriptor(chan);
1555 	int busy = ppc440spe_chan_is_busy(chan);
1556 	int seen_current = 0, slot_cnt = 0, slots_per_op = 0;
1557 
1558 	dev_dbg(chan->device->common.dev, "ppc440spe adma%d: %s\n",
1559 		chan->device->id, __func__);
1560 
1561 	if (!current_desc) {
1562 		/*  There were no transactions yet, so
1563 		 * nothing to clean
1564 		 */
1565 		return;
1566 	}
1567 
1568 	/* free completed slots from the chain starting with
1569 	 * the oldest descriptor
1570 	 */
1571 	list_for_each_entry_safe(iter, _iter, &chan->chain,
1572 					chain_node) {
1573 		dev_dbg(chan->device->common.dev, "\tcookie: %d slot: %d "
1574 		    "busy: %d this_desc: %#llx next_desc: %#x "
1575 		    "cur: %#x ack: %d\n",
1576 		    iter->async_tx.cookie, iter->idx, busy, iter->phys,
1577 		    ppc440spe_desc_get_link(iter, chan), current_desc,
1578 		    async_tx_test_ack(&iter->async_tx));
1579 		prefetch(_iter);
1580 		prefetch(&_iter->async_tx);
1581 
1582 		/* do not advance past the current descriptor loaded into the
1583 		 * hardware channel,subsequent descriptors are either in process
1584 		 * or have not been submitted
1585 		 */
1586 		if (seen_current)
1587 			break;
1588 
1589 		/* stop the search if we reach the current descriptor and the
1590 		 * channel is busy, or if it appears that the current descriptor
1591 		 * needs to be re-read (i.e. has been appended to)
1592 		 */
1593 		if (iter->phys == current_desc) {
1594 			BUG_ON(seen_current++);
1595 			if (busy || ppc440spe_desc_get_link(iter, chan)) {
1596 				/* not all descriptors of the group have
1597 				 * been completed; exit.
1598 				 */
1599 				break;
1600 			}
1601 		}
1602 
1603 		/* detect the start of a group transaction */
1604 		if (!slot_cnt && !slots_per_op) {
1605 			slot_cnt = iter->slot_cnt;
1606 			slots_per_op = iter->slots_per_op;
1607 			if (slot_cnt <= slots_per_op) {
1608 				slot_cnt = 0;
1609 				slots_per_op = 0;
1610 			}
1611 		}
1612 
1613 		if (slot_cnt) {
1614 			if (!group_start)
1615 				group_start = iter;
1616 			slot_cnt -= slots_per_op;
1617 		}
1618 
1619 		/* all the members of a group are complete */
1620 		if (slots_per_op != 0 && slot_cnt == 0) {
1621 			struct ppc440spe_adma_desc_slot *grp_iter, *_grp_iter;
1622 			int end_of_chain = 0;
1623 
1624 			/* clean up the group */
1625 			slot_cnt = group_start->slot_cnt;
1626 			grp_iter = group_start;
1627 			list_for_each_entry_safe_from(grp_iter, _grp_iter,
1628 				&chan->chain, chain_node) {
1629 
1630 				cookie = ppc440spe_adma_run_tx_complete_actions(
1631 					grp_iter, chan, cookie);
1632 
1633 				slot_cnt -= slots_per_op;
1634 				end_of_chain = ppc440spe_adma_clean_slot(
1635 				    grp_iter, chan);
1636 				if (end_of_chain && slot_cnt) {
1637 					/* Should wait for ZeroSum completion */
1638 					if (cookie > 0)
1639 						chan->common.completed_cookie = cookie;
1640 					return;
1641 				}
1642 
1643 				if (slot_cnt == 0 || end_of_chain)
1644 					break;
1645 			}
1646 
1647 			/* the group should be complete at this point */
1648 			BUG_ON(slot_cnt);
1649 
1650 			slots_per_op = 0;
1651 			group_start = NULL;
1652 			if (end_of_chain)
1653 				break;
1654 			else
1655 				continue;
1656 		} else if (slots_per_op) /* wait for group completion */
1657 			continue;
1658 
1659 		cookie = ppc440spe_adma_run_tx_complete_actions(iter, chan,
1660 		    cookie);
1661 
1662 		if (ppc440spe_adma_clean_slot(iter, chan))
1663 			break;
1664 	}
1665 
1666 	BUG_ON(!seen_current);
1667 
1668 	if (cookie > 0) {
1669 		chan->common.completed_cookie = cookie;
1670 		pr_debug("\tcompleted cookie %d\n", cookie);
1671 	}
1672 
1673 }
1674 
1675 /**
1676  * ppc440spe_adma_tasklet - clean up watch-dog initiator
1677  */
1678 static void ppc440spe_adma_tasklet(unsigned long data)
1679 {
1680 	struct ppc440spe_adma_chan *chan = (struct ppc440spe_adma_chan *) data;
1681 
1682 	spin_lock_nested(&chan->lock, SINGLE_DEPTH_NESTING);
1683 	__ppc440spe_adma_slot_cleanup(chan);
1684 	spin_unlock(&chan->lock);
1685 }
1686 
1687 /**
1688  * ppc440spe_adma_slot_cleanup - clean up scheduled initiator
1689  */
1690 static void ppc440spe_adma_slot_cleanup(struct ppc440spe_adma_chan *chan)
1691 {
1692 	spin_lock_bh(&chan->lock);
1693 	__ppc440spe_adma_slot_cleanup(chan);
1694 	spin_unlock_bh(&chan->lock);
1695 }
1696 
1697 /**
1698  * ppc440spe_adma_alloc_slots - allocate free slots (if any)
1699  */
1700 static struct ppc440spe_adma_desc_slot *ppc440spe_adma_alloc_slots(
1701 		struct ppc440spe_adma_chan *chan, int num_slots,
1702 		int slots_per_op)
1703 {
1704 	struct ppc440spe_adma_desc_slot *iter = NULL, *_iter;
1705 	struct ppc440spe_adma_desc_slot *alloc_start = NULL;
1706 	struct list_head chain = LIST_HEAD_INIT(chain);
1707 	int slots_found, retry = 0;
1708 
1709 
1710 	BUG_ON(!num_slots || !slots_per_op);
1711 	/* start search from the last allocated descrtiptor
1712 	 * if a contiguous allocation can not be found start searching
1713 	 * from the beginning of the list
1714 	 */
1715 retry:
1716 	slots_found = 0;
1717 	if (retry == 0)
1718 		iter = chan->last_used;
1719 	else
1720 		iter = list_entry(&chan->all_slots,
1721 				  struct ppc440spe_adma_desc_slot,
1722 				  slot_node);
1723 	list_for_each_entry_safe_continue(iter, _iter, &chan->all_slots,
1724 	    slot_node) {
1725 		prefetch(_iter);
1726 		prefetch(&_iter->async_tx);
1727 		if (iter->slots_per_op) {
1728 			slots_found = 0;
1729 			continue;
1730 		}
1731 
1732 		/* start the allocation if the slot is correctly aligned */
1733 		if (!slots_found++)
1734 			alloc_start = iter;
1735 
1736 		if (slots_found == num_slots) {
1737 			struct ppc440spe_adma_desc_slot *alloc_tail = NULL;
1738 			struct ppc440spe_adma_desc_slot *last_used = NULL;
1739 
1740 			iter = alloc_start;
1741 			while (num_slots) {
1742 				int i;
1743 				/* pre-ack all but the last descriptor */
1744 				if (num_slots != slots_per_op)
1745 					async_tx_ack(&iter->async_tx);
1746 
1747 				list_add_tail(&iter->chain_node, &chain);
1748 				alloc_tail = iter;
1749 				iter->async_tx.cookie = 0;
1750 				iter->hw_next = NULL;
1751 				iter->flags = 0;
1752 				iter->slot_cnt = num_slots;
1753 				iter->xor_check_result = NULL;
1754 				for (i = 0; i < slots_per_op; i++) {
1755 					iter->slots_per_op = slots_per_op - i;
1756 					last_used = iter;
1757 					iter = list_entry(iter->slot_node.next,
1758 						struct ppc440spe_adma_desc_slot,
1759 						slot_node);
1760 				}
1761 				num_slots -= slots_per_op;
1762 			}
1763 			alloc_tail->group_head = alloc_start;
1764 			alloc_tail->async_tx.cookie = -EBUSY;
1765 			list_splice(&chain, &alloc_tail->group_list);
1766 			chan->last_used = last_used;
1767 			return alloc_tail;
1768 		}
1769 	}
1770 	if (!retry++)
1771 		goto retry;
1772 
1773 	/* try to free some slots if the allocation fails */
1774 	tasklet_schedule(&chan->irq_tasklet);
1775 	return NULL;
1776 }
1777 
1778 /**
1779  * ppc440spe_adma_alloc_chan_resources -  allocate pools for CDB slots
1780  */
1781 static int ppc440spe_adma_alloc_chan_resources(struct dma_chan *chan)
1782 {
1783 	struct ppc440spe_adma_chan *ppc440spe_chan;
1784 	struct ppc440spe_adma_desc_slot *slot = NULL;
1785 	char *hw_desc;
1786 	int i, db_sz;
1787 	int init;
1788 
1789 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
1790 	init = ppc440spe_chan->slots_allocated ? 0 : 1;
1791 	chan->chan_id = ppc440spe_chan->device->id;
1792 
1793 	/* Allocate descriptor slots */
1794 	i = ppc440spe_chan->slots_allocated;
1795 	if (ppc440spe_chan->device->id != PPC440SPE_XOR_ID)
1796 		db_sz = sizeof(struct dma_cdb);
1797 	else
1798 		db_sz = sizeof(struct xor_cb);
1799 
1800 	for (; i < (ppc440spe_chan->device->pool_size / db_sz); i++) {
1801 		slot = kzalloc(sizeof(struct ppc440spe_adma_desc_slot),
1802 			       GFP_KERNEL);
1803 		if (!slot) {
1804 			printk(KERN_INFO "SPE ADMA Channel only initialized"
1805 				" %d descriptor slots", i--);
1806 			break;
1807 		}
1808 
1809 		hw_desc = (char *) ppc440spe_chan->device->dma_desc_pool_virt;
1810 		slot->hw_desc = (void *) &hw_desc[i * db_sz];
1811 		dma_async_tx_descriptor_init(&slot->async_tx, chan);
1812 		slot->async_tx.tx_submit = ppc440spe_adma_tx_submit;
1813 		INIT_LIST_HEAD(&slot->chain_node);
1814 		INIT_LIST_HEAD(&slot->slot_node);
1815 		INIT_LIST_HEAD(&slot->group_list);
1816 		slot->phys = ppc440spe_chan->device->dma_desc_pool + i * db_sz;
1817 		slot->idx = i;
1818 
1819 		spin_lock_bh(&ppc440spe_chan->lock);
1820 		ppc440spe_chan->slots_allocated++;
1821 		list_add_tail(&slot->slot_node, &ppc440spe_chan->all_slots);
1822 		spin_unlock_bh(&ppc440spe_chan->lock);
1823 	}
1824 
1825 	if (i && !ppc440spe_chan->last_used) {
1826 		ppc440spe_chan->last_used =
1827 			list_entry(ppc440spe_chan->all_slots.next,
1828 				struct ppc440spe_adma_desc_slot,
1829 				slot_node);
1830 	}
1831 
1832 	dev_dbg(ppc440spe_chan->device->common.dev,
1833 		"ppc440spe adma%d: allocated %d descriptor slots\n",
1834 		ppc440spe_chan->device->id, i);
1835 
1836 	/* initialize the channel and the chain with a null operation */
1837 	if (init) {
1838 		switch (ppc440spe_chan->device->id) {
1839 		case PPC440SPE_DMA0_ID:
1840 		case PPC440SPE_DMA1_ID:
1841 			ppc440spe_chan->hw_chain_inited = 0;
1842 			/* Use WXOR for self-testing */
1843 			if (!ppc440spe_r6_tchan)
1844 				ppc440spe_r6_tchan = ppc440spe_chan;
1845 			break;
1846 		case PPC440SPE_XOR_ID:
1847 			ppc440spe_chan_start_null_xor(ppc440spe_chan);
1848 			break;
1849 		default:
1850 			BUG();
1851 		}
1852 		ppc440spe_chan->needs_unmap = 1;
1853 	}
1854 
1855 	return (i > 0) ? i : -ENOMEM;
1856 }
1857 
1858 /**
1859  * ppc440spe_rxor_set_region_data -
1860  */
1861 static void ppc440spe_rxor_set_region(struct ppc440spe_adma_desc_slot *desc,
1862 	u8 xor_arg_no, u32 mask)
1863 {
1864 	struct xor_cb *xcb = desc->hw_desc;
1865 
1866 	xcb->ops[xor_arg_no].h |= mask;
1867 }
1868 
1869 /**
1870  * ppc440spe_rxor_set_src -
1871  */
1872 static void ppc440spe_rxor_set_src(struct ppc440spe_adma_desc_slot *desc,
1873 	u8 xor_arg_no, dma_addr_t addr)
1874 {
1875 	struct xor_cb *xcb = desc->hw_desc;
1876 
1877 	xcb->ops[xor_arg_no].h |= DMA_CUED_XOR_BASE;
1878 	xcb->ops[xor_arg_no].l = addr;
1879 }
1880 
1881 /**
1882  * ppc440spe_rxor_set_mult -
1883  */
1884 static void ppc440spe_rxor_set_mult(struct ppc440spe_adma_desc_slot *desc,
1885 	u8 xor_arg_no, u8 idx, u8 mult)
1886 {
1887 	struct xor_cb *xcb = desc->hw_desc;
1888 
1889 	xcb->ops[xor_arg_no].h |= mult << (DMA_CUED_MULT1_OFF + idx * 8);
1890 }
1891 
1892 /**
1893  * ppc440spe_adma_check_threshold - append CDBs to h/w chain if threshold
1894  *	has been achieved
1895  */
1896 static void ppc440spe_adma_check_threshold(struct ppc440spe_adma_chan *chan)
1897 {
1898 	dev_dbg(chan->device->common.dev, "ppc440spe adma%d: pending: %d\n",
1899 		chan->device->id, chan->pending);
1900 
1901 	if (chan->pending >= PPC440SPE_ADMA_THRESHOLD) {
1902 		chan->pending = 0;
1903 		ppc440spe_chan_append(chan);
1904 	}
1905 }
1906 
1907 /**
1908  * ppc440spe_adma_tx_submit - submit new descriptor group to the channel
1909  *	(it's not necessary that descriptors will be submitted to the h/w
1910  *	chains too right now)
1911  */
1912 static dma_cookie_t ppc440spe_adma_tx_submit(struct dma_async_tx_descriptor *tx)
1913 {
1914 	struct ppc440spe_adma_desc_slot *sw_desc;
1915 	struct ppc440spe_adma_chan *chan = to_ppc440spe_adma_chan(tx->chan);
1916 	struct ppc440spe_adma_desc_slot *group_start, *old_chain_tail;
1917 	int slot_cnt;
1918 	int slots_per_op;
1919 	dma_cookie_t cookie;
1920 
1921 	sw_desc = tx_to_ppc440spe_adma_slot(tx);
1922 
1923 	group_start = sw_desc->group_head;
1924 	slot_cnt = group_start->slot_cnt;
1925 	slots_per_op = group_start->slots_per_op;
1926 
1927 	spin_lock_bh(&chan->lock);
1928 	cookie = dma_cookie_assign(tx);
1929 
1930 	if (unlikely(list_empty(&chan->chain))) {
1931 		/* first peer */
1932 		list_splice_init(&sw_desc->group_list, &chan->chain);
1933 		chan_first_cdb[chan->device->id] = group_start;
1934 	} else {
1935 		/* isn't first peer, bind CDBs to chain */
1936 		old_chain_tail = list_entry(chan->chain.prev,
1937 					struct ppc440spe_adma_desc_slot,
1938 					chain_node);
1939 		list_splice_init(&sw_desc->group_list,
1940 		    &old_chain_tail->chain_node);
1941 		/* fix up the hardware chain */
1942 		ppc440spe_desc_set_link(chan, old_chain_tail, group_start);
1943 	}
1944 
1945 	/* increment the pending count by the number of operations */
1946 	chan->pending += slot_cnt / slots_per_op;
1947 	ppc440spe_adma_check_threshold(chan);
1948 	spin_unlock_bh(&chan->lock);
1949 
1950 	dev_dbg(chan->device->common.dev,
1951 		"ppc440spe adma%d: %s cookie: %d slot: %d tx %p\n",
1952 		chan->device->id, __func__,
1953 		sw_desc->async_tx.cookie, sw_desc->idx, sw_desc);
1954 
1955 	return cookie;
1956 }
1957 
1958 /**
1959  * ppc440spe_adma_prep_dma_interrupt - prepare CDB for a pseudo DMA operation
1960  */
1961 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_interrupt(
1962 		struct dma_chan *chan, unsigned long flags)
1963 {
1964 	struct ppc440spe_adma_chan *ppc440spe_chan;
1965 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
1966 	int slot_cnt, slots_per_op;
1967 
1968 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
1969 
1970 	dev_dbg(ppc440spe_chan->device->common.dev,
1971 		"ppc440spe adma%d: %s\n", ppc440spe_chan->device->id,
1972 		__func__);
1973 
1974 	spin_lock_bh(&ppc440spe_chan->lock);
1975 	slot_cnt = slots_per_op = 1;
1976 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
1977 			slots_per_op);
1978 	if (sw_desc) {
1979 		group_start = sw_desc->group_head;
1980 		ppc440spe_desc_init_interrupt(group_start, ppc440spe_chan);
1981 		group_start->unmap_len = 0;
1982 		sw_desc->async_tx.flags = flags;
1983 	}
1984 	spin_unlock_bh(&ppc440spe_chan->lock);
1985 
1986 	return sw_desc ? &sw_desc->async_tx : NULL;
1987 }
1988 
1989 /**
1990  * ppc440spe_adma_prep_dma_memcpy - prepare CDB for a MEMCPY operation
1991  */
1992 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_memcpy(
1993 		struct dma_chan *chan, dma_addr_t dma_dest,
1994 		dma_addr_t dma_src, size_t len, unsigned long flags)
1995 {
1996 	struct ppc440spe_adma_chan *ppc440spe_chan;
1997 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
1998 	int slot_cnt, slots_per_op;
1999 
2000 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2001 
2002 	if (unlikely(!len))
2003 		return NULL;
2004 
2005 	BUG_ON(len > PPC440SPE_ADMA_DMA_MAX_BYTE_COUNT);
2006 
2007 	spin_lock_bh(&ppc440spe_chan->lock);
2008 
2009 	dev_dbg(ppc440spe_chan->device->common.dev,
2010 		"ppc440spe adma%d: %s len: %u int_en %d\n",
2011 		ppc440spe_chan->device->id, __func__, len,
2012 		flags & DMA_PREP_INTERRUPT ? 1 : 0);
2013 	slot_cnt = slots_per_op = 1;
2014 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
2015 		slots_per_op);
2016 	if (sw_desc) {
2017 		group_start = sw_desc->group_head;
2018 		ppc440spe_desc_init_memcpy(group_start, flags);
2019 		ppc440spe_adma_set_dest(group_start, dma_dest, 0);
2020 		ppc440spe_adma_memcpy_xor_set_src(group_start, dma_src, 0);
2021 		ppc440spe_desc_set_byte_count(group_start, ppc440spe_chan, len);
2022 		sw_desc->unmap_len = len;
2023 		sw_desc->async_tx.flags = flags;
2024 	}
2025 	spin_unlock_bh(&ppc440spe_chan->lock);
2026 
2027 	return sw_desc ? &sw_desc->async_tx : NULL;
2028 }
2029 
2030 /**
2031  * ppc440spe_adma_prep_dma_xor - prepare CDB for a XOR operation
2032  */
2033 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_xor(
2034 		struct dma_chan *chan, dma_addr_t dma_dest,
2035 		dma_addr_t *dma_src, u32 src_cnt, size_t len,
2036 		unsigned long flags)
2037 {
2038 	struct ppc440spe_adma_chan *ppc440spe_chan;
2039 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
2040 	int slot_cnt, slots_per_op;
2041 
2042 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2043 
2044 	ADMA_LL_DBG(prep_dma_xor_dbg(ppc440spe_chan->device->id,
2045 				     dma_dest, dma_src, src_cnt));
2046 	if (unlikely(!len))
2047 		return NULL;
2048 	BUG_ON(len > PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT);
2049 
2050 	dev_dbg(ppc440spe_chan->device->common.dev,
2051 		"ppc440spe adma%d: %s src_cnt: %d len: %u int_en: %d\n",
2052 		ppc440spe_chan->device->id, __func__, src_cnt, len,
2053 		flags & DMA_PREP_INTERRUPT ? 1 : 0);
2054 
2055 	spin_lock_bh(&ppc440spe_chan->lock);
2056 	slot_cnt = ppc440spe_chan_xor_slot_count(len, src_cnt, &slots_per_op);
2057 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
2058 			slots_per_op);
2059 	if (sw_desc) {
2060 		group_start = sw_desc->group_head;
2061 		ppc440spe_desc_init_xor(group_start, src_cnt, flags);
2062 		ppc440spe_adma_set_dest(group_start, dma_dest, 0);
2063 		while (src_cnt--)
2064 			ppc440spe_adma_memcpy_xor_set_src(group_start,
2065 				dma_src[src_cnt], src_cnt);
2066 		ppc440spe_desc_set_byte_count(group_start, ppc440spe_chan, len);
2067 		sw_desc->unmap_len = len;
2068 		sw_desc->async_tx.flags = flags;
2069 	}
2070 	spin_unlock_bh(&ppc440spe_chan->lock);
2071 
2072 	return sw_desc ? &sw_desc->async_tx : NULL;
2073 }
2074 
2075 static inline void
2076 ppc440spe_desc_set_xor_src_cnt(struct ppc440spe_adma_desc_slot *desc,
2077 				int src_cnt);
2078 static void ppc440spe_init_rxor_cursor(struct ppc440spe_rxor *cursor);
2079 
2080 /**
2081  * ppc440spe_adma_init_dma2rxor_slot -
2082  */
2083 static void ppc440spe_adma_init_dma2rxor_slot(
2084 		struct ppc440spe_adma_desc_slot *desc,
2085 		dma_addr_t *src, int src_cnt)
2086 {
2087 	int i;
2088 
2089 	/* initialize CDB */
2090 	for (i = 0; i < src_cnt; i++) {
2091 		ppc440spe_adma_dma2rxor_prep_src(desc, &desc->rxor_cursor, i,
2092 						 desc->src_cnt, (u32)src[i]);
2093 	}
2094 }
2095 
2096 /**
2097  * ppc440spe_dma01_prep_mult -
2098  * for Q operation where destination is also the source
2099  */
2100 static struct ppc440spe_adma_desc_slot *ppc440spe_dma01_prep_mult(
2101 		struct ppc440spe_adma_chan *ppc440spe_chan,
2102 		dma_addr_t *dst, int dst_cnt, dma_addr_t *src, int src_cnt,
2103 		const unsigned char *scf, size_t len, unsigned long flags)
2104 {
2105 	struct ppc440spe_adma_desc_slot *sw_desc = NULL;
2106 	unsigned long op = 0;
2107 	int slot_cnt;
2108 
2109 	set_bit(PPC440SPE_DESC_WXOR, &op);
2110 	slot_cnt = 2;
2111 
2112 	spin_lock_bh(&ppc440spe_chan->lock);
2113 
2114 	/* use WXOR, each descriptor occupies one slot */
2115 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2116 	if (sw_desc) {
2117 		struct ppc440spe_adma_chan *chan;
2118 		struct ppc440spe_adma_desc_slot *iter;
2119 		struct dma_cdb *hw_desc;
2120 
2121 		chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
2122 		set_bits(op, &sw_desc->flags);
2123 		sw_desc->src_cnt = src_cnt;
2124 		sw_desc->dst_cnt = dst_cnt;
2125 		/* First descriptor, zero data in the destination and copy it
2126 		 * to q page using MULTICAST transfer.
2127 		 */
2128 		iter = list_first_entry(&sw_desc->group_list,
2129 					struct ppc440spe_adma_desc_slot,
2130 					chain_node);
2131 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2132 		/* set 'next' pointer */
2133 		iter->hw_next = list_entry(iter->chain_node.next,
2134 					   struct ppc440spe_adma_desc_slot,
2135 					   chain_node);
2136 		clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2137 		hw_desc = iter->hw_desc;
2138 		hw_desc->opc = DMA_CDB_OPC_MULTICAST;
2139 
2140 		ppc440spe_desc_set_dest_addr(iter, chan,
2141 					     DMA_CUED_XOR_BASE, dst[0], 0);
2142 		ppc440spe_desc_set_dest_addr(iter, chan, 0, dst[1], 1);
2143 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2144 					    src[0]);
2145 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2146 		iter->unmap_len = len;
2147 
2148 		/*
2149 		 * Second descriptor, multiply data from the q page
2150 		 * and store the result in real destination.
2151 		 */
2152 		iter = list_first_entry(&iter->chain_node,
2153 					struct ppc440spe_adma_desc_slot,
2154 					chain_node);
2155 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2156 		iter->hw_next = NULL;
2157 		if (flags & DMA_PREP_INTERRUPT)
2158 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
2159 		else
2160 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2161 
2162 		hw_desc = iter->hw_desc;
2163 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2164 		ppc440spe_desc_set_src_addr(iter, chan, 0,
2165 					    DMA_CUED_XOR_HB, dst[1]);
2166 		ppc440spe_desc_set_dest_addr(iter, chan,
2167 					     DMA_CUED_XOR_BASE, dst[0], 0);
2168 
2169 		ppc440spe_desc_set_src_mult(iter, chan, DMA_CUED_MULT1_OFF,
2170 					    DMA_CDB_SG_DST1, scf[0]);
2171 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2172 		iter->unmap_len = len;
2173 		sw_desc->async_tx.flags = flags;
2174 	}
2175 
2176 	spin_unlock_bh(&ppc440spe_chan->lock);
2177 
2178 	return sw_desc;
2179 }
2180 
2181 /**
2182  * ppc440spe_dma01_prep_sum_product -
2183  * Dx = A*(P+Pxy) + B*(Q+Qxy) operation where destination is also
2184  * the source.
2185  */
2186 static struct ppc440spe_adma_desc_slot *ppc440spe_dma01_prep_sum_product(
2187 		struct ppc440spe_adma_chan *ppc440spe_chan,
2188 		dma_addr_t *dst, dma_addr_t *src, int src_cnt,
2189 		const unsigned char *scf, size_t len, unsigned long flags)
2190 {
2191 	struct ppc440spe_adma_desc_slot *sw_desc = NULL;
2192 	unsigned long op = 0;
2193 	int slot_cnt;
2194 
2195 	set_bit(PPC440SPE_DESC_WXOR, &op);
2196 	slot_cnt = 3;
2197 
2198 	spin_lock_bh(&ppc440spe_chan->lock);
2199 
2200 	/* WXOR, each descriptor occupies one slot */
2201 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2202 	if (sw_desc) {
2203 		struct ppc440spe_adma_chan *chan;
2204 		struct ppc440spe_adma_desc_slot *iter;
2205 		struct dma_cdb *hw_desc;
2206 
2207 		chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
2208 		set_bits(op, &sw_desc->flags);
2209 		sw_desc->src_cnt = src_cnt;
2210 		sw_desc->dst_cnt = 1;
2211 		/* 1st descriptor, src[1] data to q page and zero destination */
2212 		iter = list_first_entry(&sw_desc->group_list,
2213 					struct ppc440spe_adma_desc_slot,
2214 					chain_node);
2215 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2216 		iter->hw_next = list_entry(iter->chain_node.next,
2217 					   struct ppc440spe_adma_desc_slot,
2218 					   chain_node);
2219 		clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2220 		hw_desc = iter->hw_desc;
2221 		hw_desc->opc = DMA_CDB_OPC_MULTICAST;
2222 
2223 		ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE,
2224 					     *dst, 0);
2225 		ppc440spe_desc_set_dest_addr(iter, chan, 0,
2226 					     ppc440spe_chan->qdest, 1);
2227 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2228 					    src[1]);
2229 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2230 		iter->unmap_len = len;
2231 
2232 		/* 2nd descriptor, multiply src[1] data and store the
2233 		 * result in destination */
2234 		iter = list_first_entry(&iter->chain_node,
2235 					struct ppc440spe_adma_desc_slot,
2236 					chain_node);
2237 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2238 		/* set 'next' pointer */
2239 		iter->hw_next = list_entry(iter->chain_node.next,
2240 					   struct ppc440spe_adma_desc_slot,
2241 					   chain_node);
2242 		if (flags & DMA_PREP_INTERRUPT)
2243 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
2244 		else
2245 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2246 
2247 		hw_desc = iter->hw_desc;
2248 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2249 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2250 					    ppc440spe_chan->qdest);
2251 		ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE,
2252 					     *dst, 0);
2253 		ppc440spe_desc_set_src_mult(iter, chan,	DMA_CUED_MULT1_OFF,
2254 					    DMA_CDB_SG_DST1, scf[1]);
2255 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2256 		iter->unmap_len = len;
2257 
2258 		/*
2259 		 * 3rd descriptor, multiply src[0] data and xor it
2260 		 * with destination
2261 		 */
2262 		iter = list_first_entry(&iter->chain_node,
2263 					struct ppc440spe_adma_desc_slot,
2264 					chain_node);
2265 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2266 		iter->hw_next = NULL;
2267 		if (flags & DMA_PREP_INTERRUPT)
2268 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
2269 		else
2270 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2271 
2272 		hw_desc = iter->hw_desc;
2273 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2274 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2275 					    src[0]);
2276 		ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE,
2277 					     *dst, 0);
2278 		ppc440spe_desc_set_src_mult(iter, chan, DMA_CUED_MULT1_OFF,
2279 					    DMA_CDB_SG_DST1, scf[0]);
2280 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2281 		iter->unmap_len = len;
2282 		sw_desc->async_tx.flags = flags;
2283 	}
2284 
2285 	spin_unlock_bh(&ppc440spe_chan->lock);
2286 
2287 	return sw_desc;
2288 }
2289 
2290 static struct ppc440spe_adma_desc_slot *ppc440spe_dma01_prep_pq(
2291 		struct ppc440spe_adma_chan *ppc440spe_chan,
2292 		dma_addr_t *dst, int dst_cnt, dma_addr_t *src, int src_cnt,
2293 		const unsigned char *scf, size_t len, unsigned long flags)
2294 {
2295 	int slot_cnt;
2296 	struct ppc440spe_adma_desc_slot *sw_desc = NULL, *iter;
2297 	unsigned long op = 0;
2298 	unsigned char mult = 1;
2299 
2300 	pr_debug("%s: dst_cnt %d, src_cnt %d, len %d\n",
2301 		 __func__, dst_cnt, src_cnt, len);
2302 	/*  select operations WXOR/RXOR depending on the
2303 	 * source addresses of operators and the number
2304 	 * of destinations (RXOR support only Q-parity calculations)
2305 	 */
2306 	set_bit(PPC440SPE_DESC_WXOR, &op);
2307 	if (!test_and_set_bit(PPC440SPE_RXOR_RUN, &ppc440spe_rxor_state)) {
2308 		/* no active RXOR;
2309 		 * do RXOR if:
2310 		 * - there are more than 1 source,
2311 		 * - len is aligned on 512-byte boundary,
2312 		 * - source addresses fit to one of 4 possible regions.
2313 		 */
2314 		if (src_cnt > 1 &&
2315 		    !(len & MQ0_CF2H_RXOR_BS_MASK) &&
2316 		    (src[0] + len) == src[1]) {
2317 			/* may do RXOR R1 R2 */
2318 			set_bit(PPC440SPE_DESC_RXOR, &op);
2319 			if (src_cnt != 2) {
2320 				/* may try to enhance region of RXOR */
2321 				if ((src[1] + len) == src[2]) {
2322 					/* do RXOR R1 R2 R3 */
2323 					set_bit(PPC440SPE_DESC_RXOR123,
2324 						&op);
2325 				} else if ((src[1] + len * 2) == src[2]) {
2326 					/* do RXOR R1 R2 R4 */
2327 					set_bit(PPC440SPE_DESC_RXOR124, &op);
2328 				} else if ((src[1] + len * 3) == src[2]) {
2329 					/* do RXOR R1 R2 R5 */
2330 					set_bit(PPC440SPE_DESC_RXOR125,
2331 						&op);
2332 				} else {
2333 					/* do RXOR R1 R2 */
2334 					set_bit(PPC440SPE_DESC_RXOR12,
2335 						&op);
2336 				}
2337 			} else {
2338 				/* do RXOR R1 R2 */
2339 				set_bit(PPC440SPE_DESC_RXOR12, &op);
2340 			}
2341 		}
2342 
2343 		if (!test_bit(PPC440SPE_DESC_RXOR, &op)) {
2344 			/* can not do this operation with RXOR */
2345 			clear_bit(PPC440SPE_RXOR_RUN,
2346 				&ppc440spe_rxor_state);
2347 		} else {
2348 			/* can do; set block size right now */
2349 			ppc440spe_desc_set_rxor_block_size(len);
2350 		}
2351 	}
2352 
2353 	/* Number of necessary slots depends on operation type selected */
2354 	if (!test_bit(PPC440SPE_DESC_RXOR, &op)) {
2355 		/*  This is a WXOR only chain. Need descriptors for each
2356 		 * source to GF-XOR them with WXOR, and need descriptors
2357 		 * for each destination to zero them with WXOR
2358 		 */
2359 		slot_cnt = src_cnt;
2360 
2361 		if (flags & DMA_PREP_ZERO_P) {
2362 			slot_cnt++;
2363 			set_bit(PPC440SPE_ZERO_P, &op);
2364 		}
2365 		if (flags & DMA_PREP_ZERO_Q) {
2366 			slot_cnt++;
2367 			set_bit(PPC440SPE_ZERO_Q, &op);
2368 		}
2369 	} else {
2370 		/*  Need 1/2 descriptor for RXOR operation, and
2371 		 * need (src_cnt - (2 or 3)) for WXOR of sources
2372 		 * remained (if any)
2373 		 */
2374 		slot_cnt = dst_cnt;
2375 
2376 		if (flags & DMA_PREP_ZERO_P)
2377 			set_bit(PPC440SPE_ZERO_P, &op);
2378 		if (flags & DMA_PREP_ZERO_Q)
2379 			set_bit(PPC440SPE_ZERO_Q, &op);
2380 
2381 		if (test_bit(PPC440SPE_DESC_RXOR12, &op))
2382 			slot_cnt += src_cnt - 2;
2383 		else
2384 			slot_cnt += src_cnt - 3;
2385 
2386 		/*  Thus we have either RXOR only chain or
2387 		 * mixed RXOR/WXOR
2388 		 */
2389 		if (slot_cnt == dst_cnt)
2390 			/* RXOR only chain */
2391 			clear_bit(PPC440SPE_DESC_WXOR, &op);
2392 	}
2393 
2394 	spin_lock_bh(&ppc440spe_chan->lock);
2395 	/* for both RXOR/WXOR each descriptor occupies one slot */
2396 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2397 	if (sw_desc) {
2398 		ppc440spe_desc_init_dma01pq(sw_desc, dst_cnt, src_cnt,
2399 				flags, op);
2400 
2401 		/* setup dst/src/mult */
2402 		pr_debug("%s: set dst descriptor 0, 1: 0x%016llx, 0x%016llx\n",
2403 			 __func__, dst[0], dst[1]);
2404 		ppc440spe_adma_pq_set_dest(sw_desc, dst, flags);
2405 		while (src_cnt--) {
2406 			ppc440spe_adma_pq_set_src(sw_desc, src[src_cnt],
2407 						  src_cnt);
2408 
2409 			/* NOTE: "Multi = 0 is equivalent to = 1" as it
2410 			 * stated in 440SPSPe_RAID6_Addendum_UM_1_17.pdf
2411 			 * doesn't work for RXOR with DMA0/1! Instead, multi=0
2412 			 * leads to zeroing source data after RXOR.
2413 			 * So, for P case set-up mult=1 explicitly.
2414 			 */
2415 			if (!(flags & DMA_PREP_PQ_DISABLE_Q))
2416 				mult = scf[src_cnt];
2417 			ppc440spe_adma_pq_set_src_mult(sw_desc,
2418 				mult, src_cnt,  dst_cnt - 1);
2419 		}
2420 
2421 		/* Setup byte count foreach slot just allocated */
2422 		sw_desc->async_tx.flags = flags;
2423 		list_for_each_entry(iter, &sw_desc->group_list,
2424 				chain_node) {
2425 			ppc440spe_desc_set_byte_count(iter,
2426 				ppc440spe_chan, len);
2427 			iter->unmap_len = len;
2428 		}
2429 	}
2430 	spin_unlock_bh(&ppc440spe_chan->lock);
2431 
2432 	return sw_desc;
2433 }
2434 
2435 static struct ppc440spe_adma_desc_slot *ppc440spe_dma2_prep_pq(
2436 		struct ppc440spe_adma_chan *ppc440spe_chan,
2437 		dma_addr_t *dst, int dst_cnt, dma_addr_t *src, int src_cnt,
2438 		const unsigned char *scf, size_t len, unsigned long flags)
2439 {
2440 	int slot_cnt, descs_per_op;
2441 	struct ppc440spe_adma_desc_slot *sw_desc = NULL, *iter;
2442 	unsigned long op = 0;
2443 	unsigned char mult = 1;
2444 
2445 	BUG_ON(!dst_cnt);
2446 	/*pr_debug("%s: dst_cnt %d, src_cnt %d, len %d\n",
2447 		 __func__, dst_cnt, src_cnt, len);*/
2448 
2449 	spin_lock_bh(&ppc440spe_chan->lock);
2450 	descs_per_op = ppc440spe_dma2_pq_slot_count(src, src_cnt, len);
2451 	if (descs_per_op < 0) {
2452 		spin_unlock_bh(&ppc440spe_chan->lock);
2453 		return NULL;
2454 	}
2455 
2456 	/* depending on number of sources we have 1 or 2 RXOR chains */
2457 	slot_cnt = descs_per_op * dst_cnt;
2458 
2459 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2460 	if (sw_desc) {
2461 		op = slot_cnt;
2462 		sw_desc->async_tx.flags = flags;
2463 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
2464 			ppc440spe_desc_init_dma2pq(iter, dst_cnt, src_cnt,
2465 				--op ? 0 : flags);
2466 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
2467 				len);
2468 			iter->unmap_len = len;
2469 
2470 			ppc440spe_init_rxor_cursor(&(iter->rxor_cursor));
2471 			iter->rxor_cursor.len = len;
2472 			iter->descs_per_op = descs_per_op;
2473 		}
2474 		op = 0;
2475 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
2476 			op++;
2477 			if (op % descs_per_op == 0)
2478 				ppc440spe_adma_init_dma2rxor_slot(iter, src,
2479 								  src_cnt);
2480 			if (likely(!list_is_last(&iter->chain_node,
2481 						 &sw_desc->group_list))) {
2482 				/* set 'next' pointer */
2483 				iter->hw_next =
2484 					list_entry(iter->chain_node.next,
2485 						struct ppc440spe_adma_desc_slot,
2486 						chain_node);
2487 				ppc440spe_xor_set_link(iter, iter->hw_next);
2488 			} else {
2489 				/* this is the last descriptor. */
2490 				iter->hw_next = NULL;
2491 			}
2492 		}
2493 
2494 		/* fixup head descriptor */
2495 		sw_desc->dst_cnt = dst_cnt;
2496 		if (flags & DMA_PREP_ZERO_P)
2497 			set_bit(PPC440SPE_ZERO_P, &sw_desc->flags);
2498 		if (flags & DMA_PREP_ZERO_Q)
2499 			set_bit(PPC440SPE_ZERO_Q, &sw_desc->flags);
2500 
2501 		/* setup dst/src/mult */
2502 		ppc440spe_adma_pq_set_dest(sw_desc, dst, flags);
2503 
2504 		while (src_cnt--) {
2505 			/* handle descriptors (if dst_cnt == 2) inside
2506 			 * the ppc440spe_adma_pq_set_srcxxx() functions
2507 			 */
2508 			ppc440spe_adma_pq_set_src(sw_desc, src[src_cnt],
2509 						  src_cnt);
2510 			if (!(flags & DMA_PREP_PQ_DISABLE_Q))
2511 				mult = scf[src_cnt];
2512 			ppc440spe_adma_pq_set_src_mult(sw_desc,
2513 					mult, src_cnt, dst_cnt - 1);
2514 		}
2515 	}
2516 	spin_unlock_bh(&ppc440spe_chan->lock);
2517 	ppc440spe_desc_set_rxor_block_size(len);
2518 	return sw_desc;
2519 }
2520 
2521 /**
2522  * ppc440spe_adma_prep_dma_pq - prepare CDB (group) for a GF-XOR operation
2523  */
2524 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_pq(
2525 		struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
2526 		unsigned int src_cnt, const unsigned char *scf,
2527 		size_t len, unsigned long flags)
2528 {
2529 	struct ppc440spe_adma_chan *ppc440spe_chan;
2530 	struct ppc440spe_adma_desc_slot *sw_desc = NULL;
2531 	int dst_cnt = 0;
2532 
2533 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2534 
2535 	ADMA_LL_DBG(prep_dma_pq_dbg(ppc440spe_chan->device->id,
2536 				    dst, src, src_cnt));
2537 	BUG_ON(!len);
2538 	BUG_ON(len > PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT);
2539 	BUG_ON(!src_cnt);
2540 
2541 	if (src_cnt == 1 && dst[1] == src[0]) {
2542 		dma_addr_t dest[2];
2543 
2544 		/* dst[1] is real destination (Q) */
2545 		dest[0] = dst[1];
2546 		/* this is the page to multicast source data to */
2547 		dest[1] = ppc440spe_chan->qdest;
2548 		sw_desc = ppc440spe_dma01_prep_mult(ppc440spe_chan,
2549 				dest, 2, src, src_cnt, scf, len, flags);
2550 		return sw_desc ? &sw_desc->async_tx : NULL;
2551 	}
2552 
2553 	if (src_cnt == 2 && dst[1] == src[1]) {
2554 		sw_desc = ppc440spe_dma01_prep_sum_product(ppc440spe_chan,
2555 					&dst[1], src, 2, scf, len, flags);
2556 		return sw_desc ? &sw_desc->async_tx : NULL;
2557 	}
2558 
2559 	if (!(flags & DMA_PREP_PQ_DISABLE_P)) {
2560 		BUG_ON(!dst[0]);
2561 		dst_cnt++;
2562 		flags |= DMA_PREP_ZERO_P;
2563 	}
2564 
2565 	if (!(flags & DMA_PREP_PQ_DISABLE_Q)) {
2566 		BUG_ON(!dst[1]);
2567 		dst_cnt++;
2568 		flags |= DMA_PREP_ZERO_Q;
2569 	}
2570 
2571 	BUG_ON(!dst_cnt);
2572 
2573 	dev_dbg(ppc440spe_chan->device->common.dev,
2574 		"ppc440spe adma%d: %s src_cnt: %d len: %u int_en: %d\n",
2575 		ppc440spe_chan->device->id, __func__, src_cnt, len,
2576 		flags & DMA_PREP_INTERRUPT ? 1 : 0);
2577 
2578 	switch (ppc440spe_chan->device->id) {
2579 	case PPC440SPE_DMA0_ID:
2580 	case PPC440SPE_DMA1_ID:
2581 		sw_desc = ppc440spe_dma01_prep_pq(ppc440spe_chan,
2582 				dst, dst_cnt, src, src_cnt, scf,
2583 				len, flags);
2584 		break;
2585 
2586 	case PPC440SPE_XOR_ID:
2587 		sw_desc = ppc440spe_dma2_prep_pq(ppc440spe_chan,
2588 				dst, dst_cnt, src, src_cnt, scf,
2589 				len, flags);
2590 		break;
2591 	}
2592 
2593 	return sw_desc ? &sw_desc->async_tx : NULL;
2594 }
2595 
2596 /**
2597  * ppc440spe_adma_prep_dma_pqzero_sum - prepare CDB group for
2598  * a PQ_ZERO_SUM operation
2599  */
2600 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_pqzero_sum(
2601 		struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
2602 		unsigned int src_cnt, const unsigned char *scf, size_t len,
2603 		enum sum_check_flags *pqres, unsigned long flags)
2604 {
2605 	struct ppc440spe_adma_chan *ppc440spe_chan;
2606 	struct ppc440spe_adma_desc_slot *sw_desc, *iter;
2607 	dma_addr_t pdest, qdest;
2608 	int slot_cnt, slots_per_op, idst, dst_cnt;
2609 
2610 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2611 
2612 	if (flags & DMA_PREP_PQ_DISABLE_P)
2613 		pdest = 0;
2614 	else
2615 		pdest = pq[0];
2616 
2617 	if (flags & DMA_PREP_PQ_DISABLE_Q)
2618 		qdest = 0;
2619 	else
2620 		qdest = pq[1];
2621 
2622 	ADMA_LL_DBG(prep_dma_pqzero_sum_dbg(ppc440spe_chan->device->id,
2623 					    src, src_cnt, scf));
2624 
2625 	/* Always use WXOR for P/Q calculations (two destinations).
2626 	 * Need 1 or 2 extra slots to verify results are zero.
2627 	 */
2628 	idst = dst_cnt = (pdest && qdest) ? 2 : 1;
2629 
2630 	/* One additional slot per destination to clone P/Q
2631 	 * before calculation (we have to preserve destinations).
2632 	 */
2633 	slot_cnt = src_cnt + dst_cnt * 2;
2634 	slots_per_op = 1;
2635 
2636 	spin_lock_bh(&ppc440spe_chan->lock);
2637 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
2638 					     slots_per_op);
2639 	if (sw_desc) {
2640 		ppc440spe_desc_init_dma01pqzero_sum(sw_desc, dst_cnt, src_cnt);
2641 
2642 		/* Setup byte count for each slot just allocated */
2643 		sw_desc->async_tx.flags = flags;
2644 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
2645 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
2646 						      len);
2647 			iter->unmap_len = len;
2648 		}
2649 
2650 		if (pdest) {
2651 			struct dma_cdb *hw_desc;
2652 			struct ppc440spe_adma_chan *chan;
2653 
2654 			iter = sw_desc->group_head;
2655 			chan = to_ppc440spe_adma_chan(iter->async_tx.chan);
2656 			memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2657 			iter->hw_next = list_entry(iter->chain_node.next,
2658 						struct ppc440spe_adma_desc_slot,
2659 						chain_node);
2660 			hw_desc = iter->hw_desc;
2661 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2662 			iter->src_cnt = 0;
2663 			iter->dst_cnt = 0;
2664 			ppc440spe_desc_set_dest_addr(iter, chan, 0,
2665 						     ppc440spe_chan->pdest, 0);
2666 			ppc440spe_desc_set_src_addr(iter, chan, 0, 0, pdest);
2667 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
2668 						      len);
2669 			iter->unmap_len = 0;
2670 			/* override pdest to preserve original P */
2671 			pdest = ppc440spe_chan->pdest;
2672 		}
2673 		if (qdest) {
2674 			struct dma_cdb *hw_desc;
2675 			struct ppc440spe_adma_chan *chan;
2676 
2677 			iter = list_first_entry(&sw_desc->group_list,
2678 						struct ppc440spe_adma_desc_slot,
2679 						chain_node);
2680 			chan = to_ppc440spe_adma_chan(iter->async_tx.chan);
2681 
2682 			if (pdest) {
2683 				iter = list_entry(iter->chain_node.next,
2684 						struct ppc440spe_adma_desc_slot,
2685 						chain_node);
2686 			}
2687 
2688 			memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2689 			iter->hw_next = list_entry(iter->chain_node.next,
2690 						struct ppc440spe_adma_desc_slot,
2691 						chain_node);
2692 			hw_desc = iter->hw_desc;
2693 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2694 			iter->src_cnt = 0;
2695 			iter->dst_cnt = 0;
2696 			ppc440spe_desc_set_dest_addr(iter, chan, 0,
2697 						     ppc440spe_chan->qdest, 0);
2698 			ppc440spe_desc_set_src_addr(iter, chan, 0, 0, qdest);
2699 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
2700 						      len);
2701 			iter->unmap_len = 0;
2702 			/* override qdest to preserve original Q */
2703 			qdest = ppc440spe_chan->qdest;
2704 		}
2705 
2706 		/* Setup destinations for P/Q ops */
2707 		ppc440spe_adma_pqzero_sum_set_dest(sw_desc, pdest, qdest);
2708 
2709 		/* Setup zero QWORDs into DCHECK CDBs */
2710 		idst = dst_cnt;
2711 		list_for_each_entry_reverse(iter, &sw_desc->group_list,
2712 					    chain_node) {
2713 			/*
2714 			 * The last CDB corresponds to Q-parity check,
2715 			 * the one before last CDB corresponds
2716 			 * P-parity check
2717 			 */
2718 			if (idst == DMA_DEST_MAX_NUM) {
2719 				if (idst == dst_cnt) {
2720 					set_bit(PPC440SPE_DESC_QCHECK,
2721 						&iter->flags);
2722 				} else {
2723 					set_bit(PPC440SPE_DESC_PCHECK,
2724 						&iter->flags);
2725 				}
2726 			} else {
2727 				if (qdest) {
2728 					set_bit(PPC440SPE_DESC_QCHECK,
2729 						&iter->flags);
2730 				} else {
2731 					set_bit(PPC440SPE_DESC_PCHECK,
2732 						&iter->flags);
2733 				}
2734 			}
2735 			iter->xor_check_result = pqres;
2736 
2737 			/*
2738 			 * set it to zero, if check fail then result will
2739 			 * be updated
2740 			 */
2741 			*iter->xor_check_result = 0;
2742 			ppc440spe_desc_set_dcheck(iter, ppc440spe_chan,
2743 				ppc440spe_qword);
2744 
2745 			if (!(--dst_cnt))
2746 				break;
2747 		}
2748 
2749 		/* Setup sources and mults for P/Q ops */
2750 		list_for_each_entry_continue_reverse(iter, &sw_desc->group_list,
2751 						     chain_node) {
2752 			struct ppc440spe_adma_chan *chan;
2753 			u32 mult_dst;
2754 
2755 			chan = to_ppc440spe_adma_chan(iter->async_tx.chan);
2756 			ppc440spe_desc_set_src_addr(iter, chan, 0,
2757 						    DMA_CUED_XOR_HB,
2758 						    src[src_cnt - 1]);
2759 			if (qdest) {
2760 				mult_dst = (dst_cnt - 1) ? DMA_CDB_SG_DST2 :
2761 							   DMA_CDB_SG_DST1;
2762 				ppc440spe_desc_set_src_mult(iter, chan,
2763 							    DMA_CUED_MULT1_OFF,
2764 							    mult_dst,
2765 							    scf[src_cnt - 1]);
2766 			}
2767 			if (!(--src_cnt))
2768 				break;
2769 		}
2770 	}
2771 	spin_unlock_bh(&ppc440spe_chan->lock);
2772 	return sw_desc ? &sw_desc->async_tx : NULL;
2773 }
2774 
2775 /**
2776  * ppc440spe_adma_prep_dma_xor_zero_sum - prepare CDB group for
2777  * XOR ZERO_SUM operation
2778  */
2779 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_xor_zero_sum(
2780 		struct dma_chan *chan, dma_addr_t *src, unsigned int src_cnt,
2781 		size_t len, enum sum_check_flags *result, unsigned long flags)
2782 {
2783 	struct dma_async_tx_descriptor *tx;
2784 	dma_addr_t pq[2];
2785 
2786 	/* validate P, disable Q */
2787 	pq[0] = src[0];
2788 	pq[1] = 0;
2789 	flags |= DMA_PREP_PQ_DISABLE_Q;
2790 
2791 	tx = ppc440spe_adma_prep_dma_pqzero_sum(chan, pq, &src[1],
2792 						src_cnt - 1, 0, len,
2793 						result, flags);
2794 	return tx;
2795 }
2796 
2797 /**
2798  * ppc440spe_adma_set_dest - set destination address into descriptor
2799  */
2800 static void ppc440spe_adma_set_dest(struct ppc440spe_adma_desc_slot *sw_desc,
2801 		dma_addr_t addr, int index)
2802 {
2803 	struct ppc440spe_adma_chan *chan;
2804 
2805 	BUG_ON(index >= sw_desc->dst_cnt);
2806 
2807 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
2808 
2809 	switch (chan->device->id) {
2810 	case PPC440SPE_DMA0_ID:
2811 	case PPC440SPE_DMA1_ID:
2812 		/* to do: support transfers lengths >
2813 		 * PPC440SPE_ADMA_DMA/XOR_MAX_BYTE_COUNT
2814 		 */
2815 		ppc440spe_desc_set_dest_addr(sw_desc->group_head,
2816 			chan, 0, addr, index);
2817 		break;
2818 	case PPC440SPE_XOR_ID:
2819 		sw_desc = ppc440spe_get_group_entry(sw_desc, index);
2820 		ppc440spe_desc_set_dest_addr(sw_desc,
2821 			chan, 0, addr, index);
2822 		break;
2823 	}
2824 }
2825 
2826 static void ppc440spe_adma_pq_zero_op(struct ppc440spe_adma_desc_slot *iter,
2827 		struct ppc440spe_adma_chan *chan, dma_addr_t addr)
2828 {
2829 	/*  To clear destinations update the descriptor
2830 	 * (P or Q depending on index) as follows:
2831 	 * addr is destination (0 corresponds to SG2):
2832 	 */
2833 	ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE, addr, 0);
2834 
2835 	/* ... and the addr is source: */
2836 	ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB, addr);
2837 
2838 	/* addr is always SG2 then the mult is always DST1 */
2839 	ppc440spe_desc_set_src_mult(iter, chan, DMA_CUED_MULT1_OFF,
2840 				    DMA_CDB_SG_DST1, 1);
2841 }
2842 
2843 /**
2844  * ppc440spe_adma_pq_set_dest - set destination address into descriptor
2845  * for the PQXOR operation
2846  */
2847 static void ppc440spe_adma_pq_set_dest(struct ppc440spe_adma_desc_slot *sw_desc,
2848 		dma_addr_t *addrs, unsigned long flags)
2849 {
2850 	struct ppc440spe_adma_desc_slot *iter;
2851 	struct ppc440spe_adma_chan *chan;
2852 	dma_addr_t paddr, qaddr;
2853 	dma_addr_t addr = 0, ppath, qpath;
2854 	int index = 0, i;
2855 
2856 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
2857 
2858 	if (flags & DMA_PREP_PQ_DISABLE_P)
2859 		paddr = 0;
2860 	else
2861 		paddr = addrs[0];
2862 
2863 	if (flags & DMA_PREP_PQ_DISABLE_Q)
2864 		qaddr = 0;
2865 	else
2866 		qaddr = addrs[1];
2867 
2868 	if (!paddr || !qaddr)
2869 		addr = paddr ? paddr : qaddr;
2870 
2871 	switch (chan->device->id) {
2872 	case PPC440SPE_DMA0_ID:
2873 	case PPC440SPE_DMA1_ID:
2874 		/* walk through the WXOR source list and set P/Q-destinations
2875 		 * for each slot:
2876 		 */
2877 		if (!test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags)) {
2878 			/* This is WXOR-only chain; may have 1/2 zero descs */
2879 			if (test_bit(PPC440SPE_ZERO_P, &sw_desc->flags))
2880 				index++;
2881 			if (test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags))
2882 				index++;
2883 
2884 			iter = ppc440spe_get_group_entry(sw_desc, index);
2885 			if (addr) {
2886 				/* one destination */
2887 				list_for_each_entry_from(iter,
2888 					&sw_desc->group_list, chain_node)
2889 					ppc440spe_desc_set_dest_addr(iter, chan,
2890 						DMA_CUED_XOR_BASE, addr, 0);
2891 			} else {
2892 				/* two destinations */
2893 				list_for_each_entry_from(iter,
2894 					&sw_desc->group_list, chain_node) {
2895 					ppc440spe_desc_set_dest_addr(iter, chan,
2896 						DMA_CUED_XOR_BASE, paddr, 0);
2897 					ppc440spe_desc_set_dest_addr(iter, chan,
2898 						DMA_CUED_XOR_BASE, qaddr, 1);
2899 				}
2900 			}
2901 
2902 			if (index) {
2903 				/*  To clear destinations update the descriptor
2904 				 * (1st,2nd, or both depending on flags)
2905 				 */
2906 				index = 0;
2907 				if (test_bit(PPC440SPE_ZERO_P,
2908 						&sw_desc->flags)) {
2909 					iter = ppc440spe_get_group_entry(
2910 							sw_desc, index++);
2911 					ppc440spe_adma_pq_zero_op(iter, chan,
2912 							paddr);
2913 				}
2914 
2915 				if (test_bit(PPC440SPE_ZERO_Q,
2916 						&sw_desc->flags)) {
2917 					iter = ppc440spe_get_group_entry(
2918 							sw_desc, index++);
2919 					ppc440spe_adma_pq_zero_op(iter, chan,
2920 							qaddr);
2921 				}
2922 
2923 				return;
2924 			}
2925 		} else {
2926 			/* This is RXOR-only or RXOR/WXOR mixed chain */
2927 
2928 			/* If we want to include destination into calculations,
2929 			 * then make dest addresses cued with mult=1 (XOR).
2930 			 */
2931 			ppath = test_bit(PPC440SPE_ZERO_P, &sw_desc->flags) ?
2932 					DMA_CUED_XOR_HB :
2933 					DMA_CUED_XOR_BASE |
2934 						(1 << DMA_CUED_MULT1_OFF);
2935 			qpath = test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags) ?
2936 					DMA_CUED_XOR_HB :
2937 					DMA_CUED_XOR_BASE |
2938 						(1 << DMA_CUED_MULT1_OFF);
2939 
2940 			/* Setup destination(s) in RXOR slot(s) */
2941 			iter = ppc440spe_get_group_entry(sw_desc, index++);
2942 			ppc440spe_desc_set_dest_addr(iter, chan,
2943 						paddr ? ppath : qpath,
2944 						paddr ? paddr : qaddr, 0);
2945 			if (!addr) {
2946 				/* two destinations */
2947 				iter = ppc440spe_get_group_entry(sw_desc,
2948 								 index++);
2949 				ppc440spe_desc_set_dest_addr(iter, chan,
2950 						qpath, qaddr, 0);
2951 			}
2952 
2953 			if (test_bit(PPC440SPE_DESC_WXOR, &sw_desc->flags)) {
2954 				/* Setup destination(s) in remaining WXOR
2955 				 * slots
2956 				 */
2957 				iter = ppc440spe_get_group_entry(sw_desc,
2958 								 index);
2959 				if (addr) {
2960 					/* one destination */
2961 					list_for_each_entry_from(iter,
2962 					    &sw_desc->group_list,
2963 					    chain_node)
2964 						ppc440spe_desc_set_dest_addr(
2965 							iter, chan,
2966 							DMA_CUED_XOR_BASE,
2967 							addr, 0);
2968 
2969 				} else {
2970 					/* two destinations */
2971 					list_for_each_entry_from(iter,
2972 					    &sw_desc->group_list,
2973 					    chain_node) {
2974 						ppc440spe_desc_set_dest_addr(
2975 							iter, chan,
2976 							DMA_CUED_XOR_BASE,
2977 							paddr, 0);
2978 						ppc440spe_desc_set_dest_addr(
2979 							iter, chan,
2980 							DMA_CUED_XOR_BASE,
2981 							qaddr, 1);
2982 					}
2983 				}
2984 			}
2985 
2986 		}
2987 		break;
2988 
2989 	case PPC440SPE_XOR_ID:
2990 		/* DMA2 descriptors have only 1 destination, so there are
2991 		 * two chains - one for each dest.
2992 		 * If we want to include destination into calculations,
2993 		 * then make dest addresses cued with mult=1 (XOR).
2994 		 */
2995 		ppath = test_bit(PPC440SPE_ZERO_P, &sw_desc->flags) ?
2996 				DMA_CUED_XOR_HB :
2997 				DMA_CUED_XOR_BASE |
2998 					(1 << DMA_CUED_MULT1_OFF);
2999 
3000 		qpath = test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags) ?
3001 				DMA_CUED_XOR_HB :
3002 				DMA_CUED_XOR_BASE |
3003 					(1 << DMA_CUED_MULT1_OFF);
3004 
3005 		iter = ppc440spe_get_group_entry(sw_desc, 0);
3006 		for (i = 0; i < sw_desc->descs_per_op; i++) {
3007 			ppc440spe_desc_set_dest_addr(iter, chan,
3008 				paddr ? ppath : qpath,
3009 				paddr ? paddr : qaddr, 0);
3010 			iter = list_entry(iter->chain_node.next,
3011 					  struct ppc440spe_adma_desc_slot,
3012 					  chain_node);
3013 		}
3014 
3015 		if (!addr) {
3016 			/* Two destinations; setup Q here */
3017 			iter = ppc440spe_get_group_entry(sw_desc,
3018 				sw_desc->descs_per_op);
3019 			for (i = 0; i < sw_desc->descs_per_op; i++) {
3020 				ppc440spe_desc_set_dest_addr(iter,
3021 					chan, qpath, qaddr, 0);
3022 				iter = list_entry(iter->chain_node.next,
3023 						struct ppc440spe_adma_desc_slot,
3024 						chain_node);
3025 			}
3026 		}
3027 
3028 		break;
3029 	}
3030 }
3031 
3032 /**
3033  * ppc440spe_adma_pq_zero_sum_set_dest - set destination address into descriptor
3034  * for the PQ_ZERO_SUM operation
3035  */
3036 static void ppc440spe_adma_pqzero_sum_set_dest(
3037 		struct ppc440spe_adma_desc_slot *sw_desc,
3038 		dma_addr_t paddr, dma_addr_t qaddr)
3039 {
3040 	struct ppc440spe_adma_desc_slot *iter, *end;
3041 	struct ppc440spe_adma_chan *chan;
3042 	dma_addr_t addr = 0;
3043 	int idx;
3044 
3045 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3046 
3047 	/* walk through the WXOR source list and set P/Q-destinations
3048 	 * for each slot
3049 	 */
3050 	idx = (paddr && qaddr) ? 2 : 1;
3051 	/* set end */
3052 	list_for_each_entry_reverse(end, &sw_desc->group_list,
3053 				    chain_node) {
3054 		if (!(--idx))
3055 			break;
3056 	}
3057 	/* set start */
3058 	idx = (paddr && qaddr) ? 2 : 1;
3059 	iter = ppc440spe_get_group_entry(sw_desc, idx);
3060 
3061 	if (paddr && qaddr) {
3062 		/* two destinations */
3063 		list_for_each_entry_from(iter, &sw_desc->group_list,
3064 					 chain_node) {
3065 			if (unlikely(iter == end))
3066 				break;
3067 			ppc440spe_desc_set_dest_addr(iter, chan,
3068 						DMA_CUED_XOR_BASE, paddr, 0);
3069 			ppc440spe_desc_set_dest_addr(iter, chan,
3070 						DMA_CUED_XOR_BASE, qaddr, 1);
3071 		}
3072 	} else {
3073 		/* one destination */
3074 		addr = paddr ? paddr : qaddr;
3075 		list_for_each_entry_from(iter, &sw_desc->group_list,
3076 					 chain_node) {
3077 			if (unlikely(iter == end))
3078 				break;
3079 			ppc440spe_desc_set_dest_addr(iter, chan,
3080 						DMA_CUED_XOR_BASE, addr, 0);
3081 		}
3082 	}
3083 
3084 	/*  The remaining descriptors are DATACHECK. These have no need in
3085 	 * destination. Actually, these destinations are used there
3086 	 * as sources for check operation. So, set addr as source.
3087 	 */
3088 	ppc440spe_desc_set_src_addr(end, chan, 0, 0, addr ? addr : paddr);
3089 
3090 	if (!addr) {
3091 		end = list_entry(end->chain_node.next,
3092 				 struct ppc440spe_adma_desc_slot, chain_node);
3093 		ppc440spe_desc_set_src_addr(end, chan, 0, 0, qaddr);
3094 	}
3095 }
3096 
3097 /**
3098  * ppc440spe_desc_set_xor_src_cnt - set source count into descriptor
3099  */
3100 static inline void ppc440spe_desc_set_xor_src_cnt(
3101 			struct ppc440spe_adma_desc_slot *desc,
3102 			int src_cnt)
3103 {
3104 	struct xor_cb *hw_desc = desc->hw_desc;
3105 
3106 	hw_desc->cbc &= ~XOR_CDCR_OAC_MSK;
3107 	hw_desc->cbc |= src_cnt;
3108 }
3109 
3110 /**
3111  * ppc440spe_adma_pq_set_src - set source address into descriptor
3112  */
3113 static void ppc440spe_adma_pq_set_src(struct ppc440spe_adma_desc_slot *sw_desc,
3114 		dma_addr_t addr, int index)
3115 {
3116 	struct ppc440spe_adma_chan *chan;
3117 	dma_addr_t haddr = 0;
3118 	struct ppc440spe_adma_desc_slot *iter = NULL;
3119 
3120 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3121 
3122 	switch (chan->device->id) {
3123 	case PPC440SPE_DMA0_ID:
3124 	case PPC440SPE_DMA1_ID:
3125 		/* DMA0,1 may do: WXOR, RXOR, RXOR+WXORs chain
3126 		 */
3127 		if (test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags)) {
3128 			/* RXOR-only or RXOR/WXOR operation */
3129 			int iskip = test_bit(PPC440SPE_DESC_RXOR12,
3130 				&sw_desc->flags) ?  2 : 3;
3131 
3132 			if (index == 0) {
3133 				/* 1st slot (RXOR) */
3134 				/* setup sources region (R1-2-3, R1-2-4,
3135 				 * or R1-2-5)
3136 				 */
3137 				if (test_bit(PPC440SPE_DESC_RXOR12,
3138 						&sw_desc->flags))
3139 					haddr = DMA_RXOR12 <<
3140 						DMA_CUED_REGION_OFF;
3141 				else if (test_bit(PPC440SPE_DESC_RXOR123,
3142 				    &sw_desc->flags))
3143 					haddr = DMA_RXOR123 <<
3144 						DMA_CUED_REGION_OFF;
3145 				else if (test_bit(PPC440SPE_DESC_RXOR124,
3146 				    &sw_desc->flags))
3147 					haddr = DMA_RXOR124 <<
3148 						DMA_CUED_REGION_OFF;
3149 				else if (test_bit(PPC440SPE_DESC_RXOR125,
3150 				    &sw_desc->flags))
3151 					haddr = DMA_RXOR125 <<
3152 						DMA_CUED_REGION_OFF;
3153 				else
3154 					BUG();
3155 				haddr |= DMA_CUED_XOR_BASE;
3156 				iter = ppc440spe_get_group_entry(sw_desc, 0);
3157 			} else if (index < iskip) {
3158 				/* 1st slot (RXOR)
3159 				 * shall actually set source address only once
3160 				 * instead of first <iskip>
3161 				 */
3162 				iter = NULL;
3163 			} else {
3164 				/* 2nd/3d and next slots (WXOR);
3165 				 * skip first slot with RXOR
3166 				 */
3167 				haddr = DMA_CUED_XOR_HB;
3168 				iter = ppc440spe_get_group_entry(sw_desc,
3169 				    index - iskip + sw_desc->dst_cnt);
3170 			}
3171 		} else {
3172 			int znum = 0;
3173 
3174 			/* WXOR-only operation; skip first slots with
3175 			 * zeroing destinations
3176 			 */
3177 			if (test_bit(PPC440SPE_ZERO_P, &sw_desc->flags))
3178 				znum++;
3179 			if (test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags))
3180 				znum++;
3181 
3182 			haddr = DMA_CUED_XOR_HB;
3183 			iter = ppc440spe_get_group_entry(sw_desc,
3184 					index + znum);
3185 		}
3186 
3187 		if (likely(iter)) {
3188 			ppc440spe_desc_set_src_addr(iter, chan, 0, haddr, addr);
3189 
3190 			if (!index &&
3191 			    test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags) &&
3192 			    sw_desc->dst_cnt == 2) {
3193 				/* if we have two destinations for RXOR, then
3194 				 * setup source in the second descr too
3195 				 */
3196 				iter = ppc440spe_get_group_entry(sw_desc, 1);
3197 				ppc440spe_desc_set_src_addr(iter, chan, 0,
3198 					haddr, addr);
3199 			}
3200 		}
3201 		break;
3202 
3203 	case PPC440SPE_XOR_ID:
3204 		/* DMA2 may do Biskup */
3205 		iter = sw_desc->group_head;
3206 		if (iter->dst_cnt == 2) {
3207 			/* both P & Q calculations required; set P src here */
3208 			ppc440spe_adma_dma2rxor_set_src(iter, index, addr);
3209 
3210 			/* this is for Q */
3211 			iter = ppc440spe_get_group_entry(sw_desc,
3212 				sw_desc->descs_per_op);
3213 		}
3214 		ppc440spe_adma_dma2rxor_set_src(iter, index, addr);
3215 		break;
3216 	}
3217 }
3218 
3219 /**
3220  * ppc440spe_adma_memcpy_xor_set_src - set source address into descriptor
3221  */
3222 static void ppc440spe_adma_memcpy_xor_set_src(
3223 		struct ppc440spe_adma_desc_slot *sw_desc,
3224 		dma_addr_t addr, int index)
3225 {
3226 	struct ppc440spe_adma_chan *chan;
3227 
3228 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3229 	sw_desc = sw_desc->group_head;
3230 
3231 	if (likely(sw_desc))
3232 		ppc440spe_desc_set_src_addr(sw_desc, chan, index, 0, addr);
3233 }
3234 
3235 /**
3236  * ppc440spe_adma_dma2rxor_inc_addr  -
3237  */
3238 static void ppc440spe_adma_dma2rxor_inc_addr(
3239 		struct ppc440spe_adma_desc_slot *desc,
3240 		struct ppc440spe_rxor *cursor, int index, int src_cnt)
3241 {
3242 	cursor->addr_count++;
3243 	if (index == src_cnt - 1) {
3244 		ppc440spe_desc_set_xor_src_cnt(desc, cursor->addr_count);
3245 	} else if (cursor->addr_count == XOR_MAX_OPS) {
3246 		ppc440spe_desc_set_xor_src_cnt(desc, cursor->addr_count);
3247 		cursor->addr_count = 0;
3248 		cursor->desc_count++;
3249 	}
3250 }
3251 
3252 /**
3253  * ppc440spe_adma_dma2rxor_prep_src - setup RXOR types in DMA2 CDB
3254  */
3255 static int ppc440spe_adma_dma2rxor_prep_src(
3256 		struct ppc440spe_adma_desc_slot *hdesc,
3257 		struct ppc440spe_rxor *cursor, int index,
3258 		int src_cnt, u32 addr)
3259 {
3260 	int rval = 0;
3261 	u32 sign;
3262 	struct ppc440spe_adma_desc_slot *desc = hdesc;
3263 	int i;
3264 
3265 	for (i = 0; i < cursor->desc_count; i++) {
3266 		desc = list_entry(hdesc->chain_node.next,
3267 				  struct ppc440spe_adma_desc_slot,
3268 				  chain_node);
3269 	}
3270 
3271 	switch (cursor->state) {
3272 	case 0:
3273 		if (addr == cursor->addrl + cursor->len) {
3274 			/* direct RXOR */
3275 			cursor->state = 1;
3276 			cursor->xor_count++;
3277 			if (index == src_cnt-1) {
3278 				ppc440spe_rxor_set_region(desc,
3279 					cursor->addr_count,
3280 					DMA_RXOR12 << DMA_CUED_REGION_OFF);
3281 				ppc440spe_adma_dma2rxor_inc_addr(
3282 					desc, cursor, index, src_cnt);
3283 			}
3284 		} else if (cursor->addrl == addr + cursor->len) {
3285 			/* reverse RXOR */
3286 			cursor->state = 1;
3287 			cursor->xor_count++;
3288 			set_bit(cursor->addr_count, &desc->reverse_flags[0]);
3289 			if (index == src_cnt-1) {
3290 				ppc440spe_rxor_set_region(desc,
3291 					cursor->addr_count,
3292 					DMA_RXOR12 << DMA_CUED_REGION_OFF);
3293 				ppc440spe_adma_dma2rxor_inc_addr(
3294 					desc, cursor, index, src_cnt);
3295 			}
3296 		} else {
3297 			printk(KERN_ERR "Cannot build "
3298 				"DMA2 RXOR command block.\n");
3299 			BUG();
3300 		}
3301 		break;
3302 	case 1:
3303 		sign = test_bit(cursor->addr_count,
3304 				desc->reverse_flags)
3305 			? -1 : 1;
3306 		if (index == src_cnt-2 || (sign == -1
3307 			&& addr != cursor->addrl - 2*cursor->len)) {
3308 			cursor->state = 0;
3309 			cursor->xor_count = 1;
3310 			cursor->addrl = addr;
3311 			ppc440spe_rxor_set_region(desc,
3312 				cursor->addr_count,
3313 				DMA_RXOR12 << DMA_CUED_REGION_OFF);
3314 			ppc440spe_adma_dma2rxor_inc_addr(
3315 				desc, cursor, index, src_cnt);
3316 		} else if (addr == cursor->addrl + 2*sign*cursor->len) {
3317 			cursor->state = 2;
3318 			cursor->xor_count = 0;
3319 			ppc440spe_rxor_set_region(desc,
3320 				cursor->addr_count,
3321 				DMA_RXOR123 << DMA_CUED_REGION_OFF);
3322 			if (index == src_cnt-1) {
3323 				ppc440spe_adma_dma2rxor_inc_addr(
3324 					desc, cursor, index, src_cnt);
3325 			}
3326 		} else if (addr == cursor->addrl + 3*cursor->len) {
3327 			cursor->state = 2;
3328 			cursor->xor_count = 0;
3329 			ppc440spe_rxor_set_region(desc,
3330 				cursor->addr_count,
3331 				DMA_RXOR124 << DMA_CUED_REGION_OFF);
3332 			if (index == src_cnt-1) {
3333 				ppc440spe_adma_dma2rxor_inc_addr(
3334 					desc, cursor, index, src_cnt);
3335 			}
3336 		} else if (addr == cursor->addrl + 4*cursor->len) {
3337 			cursor->state = 2;
3338 			cursor->xor_count = 0;
3339 			ppc440spe_rxor_set_region(desc,
3340 				cursor->addr_count,
3341 				DMA_RXOR125 << DMA_CUED_REGION_OFF);
3342 			if (index == src_cnt-1) {
3343 				ppc440spe_adma_dma2rxor_inc_addr(
3344 					desc, cursor, index, src_cnt);
3345 			}
3346 		} else {
3347 			cursor->state = 0;
3348 			cursor->xor_count = 1;
3349 			cursor->addrl = addr;
3350 			ppc440spe_rxor_set_region(desc,
3351 				cursor->addr_count,
3352 				DMA_RXOR12 << DMA_CUED_REGION_OFF);
3353 			ppc440spe_adma_dma2rxor_inc_addr(
3354 				desc, cursor, index, src_cnt);
3355 		}
3356 		break;
3357 	case 2:
3358 		cursor->state = 0;
3359 		cursor->addrl = addr;
3360 		cursor->xor_count++;
3361 		if (index) {
3362 			ppc440spe_adma_dma2rxor_inc_addr(
3363 				desc, cursor, index, src_cnt);
3364 		}
3365 		break;
3366 	}
3367 
3368 	return rval;
3369 }
3370 
3371 /**
3372  * ppc440spe_adma_dma2rxor_set_src - set RXOR source address; it's assumed that
3373  *	ppc440spe_adma_dma2rxor_prep_src() has already done prior this call
3374  */
3375 static void ppc440spe_adma_dma2rxor_set_src(
3376 		struct ppc440spe_adma_desc_slot *desc,
3377 		int index, dma_addr_t addr)
3378 {
3379 	struct xor_cb *xcb = desc->hw_desc;
3380 	int k = 0, op = 0, lop = 0;
3381 
3382 	/* get the RXOR operand which corresponds to index addr */
3383 	while (op <= index) {
3384 		lop = op;
3385 		if (k == XOR_MAX_OPS) {
3386 			k = 0;
3387 			desc = list_entry(desc->chain_node.next,
3388 				struct ppc440spe_adma_desc_slot, chain_node);
3389 			xcb = desc->hw_desc;
3390 
3391 		}
3392 		if ((xcb->ops[k++].h & (DMA_RXOR12 << DMA_CUED_REGION_OFF)) ==
3393 		    (DMA_RXOR12 << DMA_CUED_REGION_OFF))
3394 			op += 2;
3395 		else
3396 			op += 3;
3397 	}
3398 
3399 	BUG_ON(k < 1);
3400 
3401 	if (test_bit(k-1, desc->reverse_flags)) {
3402 		/* reverse operand order; put last op in RXOR group */
3403 		if (index == op - 1)
3404 			ppc440spe_rxor_set_src(desc, k - 1, addr);
3405 	} else {
3406 		/* direct operand order; put first op in RXOR group */
3407 		if (index == lop)
3408 			ppc440spe_rxor_set_src(desc, k - 1, addr);
3409 	}
3410 }
3411 
3412 /**
3413  * ppc440spe_adma_dma2rxor_set_mult - set RXOR multipliers; it's assumed that
3414  *	ppc440spe_adma_dma2rxor_prep_src() has already done prior this call
3415  */
3416 static void ppc440spe_adma_dma2rxor_set_mult(
3417 		struct ppc440spe_adma_desc_slot *desc,
3418 		int index, u8 mult)
3419 {
3420 	struct xor_cb *xcb = desc->hw_desc;
3421 	int k = 0, op = 0, lop = 0;
3422 
3423 	/* get the RXOR operand which corresponds to index mult */
3424 	while (op <= index) {
3425 		lop = op;
3426 		if (k == XOR_MAX_OPS) {
3427 			k = 0;
3428 			desc = list_entry(desc->chain_node.next,
3429 					  struct ppc440spe_adma_desc_slot,
3430 					  chain_node);
3431 			xcb = desc->hw_desc;
3432 
3433 		}
3434 		if ((xcb->ops[k++].h & (DMA_RXOR12 << DMA_CUED_REGION_OFF)) ==
3435 		    (DMA_RXOR12 << DMA_CUED_REGION_OFF))
3436 			op += 2;
3437 		else
3438 			op += 3;
3439 	}
3440 
3441 	BUG_ON(k < 1);
3442 	if (test_bit(k-1, desc->reverse_flags)) {
3443 		/* reverse order */
3444 		ppc440spe_rxor_set_mult(desc, k - 1, op - index - 1, mult);
3445 	} else {
3446 		/* direct order */
3447 		ppc440spe_rxor_set_mult(desc, k - 1, index - lop, mult);
3448 	}
3449 }
3450 
3451 /**
3452  * ppc440spe_init_rxor_cursor -
3453  */
3454 static void ppc440spe_init_rxor_cursor(struct ppc440spe_rxor *cursor)
3455 {
3456 	memset(cursor, 0, sizeof(struct ppc440spe_rxor));
3457 	cursor->state = 2;
3458 }
3459 
3460 /**
3461  * ppc440spe_adma_pq_set_src_mult - set multiplication coefficient into
3462  * descriptor for the PQXOR operation
3463  */
3464 static void ppc440spe_adma_pq_set_src_mult(
3465 		struct ppc440spe_adma_desc_slot *sw_desc,
3466 		unsigned char mult, int index, int dst_pos)
3467 {
3468 	struct ppc440spe_adma_chan *chan;
3469 	u32 mult_idx, mult_dst;
3470 	struct ppc440spe_adma_desc_slot *iter = NULL, *iter1 = NULL;
3471 
3472 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3473 
3474 	switch (chan->device->id) {
3475 	case PPC440SPE_DMA0_ID:
3476 	case PPC440SPE_DMA1_ID:
3477 		if (test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags)) {
3478 			int region = test_bit(PPC440SPE_DESC_RXOR12,
3479 					&sw_desc->flags) ? 2 : 3;
3480 
3481 			if (index < region) {
3482 				/* RXOR multipliers */
3483 				iter = ppc440spe_get_group_entry(sw_desc,
3484 					sw_desc->dst_cnt - 1);
3485 				if (sw_desc->dst_cnt == 2)
3486 					iter1 = ppc440spe_get_group_entry(
3487 							sw_desc, 0);
3488 
3489 				mult_idx = DMA_CUED_MULT1_OFF + (index << 3);
3490 				mult_dst = DMA_CDB_SG_SRC;
3491 			} else {
3492 				/* WXOR multiplier */
3493 				iter = ppc440spe_get_group_entry(sw_desc,
3494 							index - region +
3495 							sw_desc->dst_cnt);
3496 				mult_idx = DMA_CUED_MULT1_OFF;
3497 				mult_dst = dst_pos ? DMA_CDB_SG_DST2 :
3498 						     DMA_CDB_SG_DST1;
3499 			}
3500 		} else {
3501 			int znum = 0;
3502 
3503 			/* WXOR-only;
3504 			 * skip first slots with destinations (if ZERO_DST has
3505 			 * place)
3506 			 */
3507 			if (test_bit(PPC440SPE_ZERO_P, &sw_desc->flags))
3508 				znum++;
3509 			if (test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags))
3510 				znum++;
3511 
3512 			iter = ppc440spe_get_group_entry(sw_desc, index + znum);
3513 			mult_idx = DMA_CUED_MULT1_OFF;
3514 			mult_dst = dst_pos ? DMA_CDB_SG_DST2 : DMA_CDB_SG_DST1;
3515 		}
3516 
3517 		if (likely(iter)) {
3518 			ppc440spe_desc_set_src_mult(iter, chan,
3519 				mult_idx, mult_dst, mult);
3520 
3521 			if (unlikely(iter1)) {
3522 				/* if we have two destinations for RXOR, then
3523 				 * we've just set Q mult. Set-up P now.
3524 				 */
3525 				ppc440spe_desc_set_src_mult(iter1, chan,
3526 					mult_idx, mult_dst, 1);
3527 			}
3528 
3529 		}
3530 		break;
3531 
3532 	case PPC440SPE_XOR_ID:
3533 		iter = sw_desc->group_head;
3534 		if (sw_desc->dst_cnt == 2) {
3535 			/* both P & Q calculations required; set P mult here */
3536 			ppc440spe_adma_dma2rxor_set_mult(iter, index, 1);
3537 
3538 			/* and then set Q mult */
3539 			iter = ppc440spe_get_group_entry(sw_desc,
3540 			       sw_desc->descs_per_op);
3541 		}
3542 		ppc440spe_adma_dma2rxor_set_mult(iter, index, mult);
3543 		break;
3544 	}
3545 }
3546 
3547 /**
3548  * ppc440spe_adma_free_chan_resources - free the resources allocated
3549  */
3550 static void ppc440spe_adma_free_chan_resources(struct dma_chan *chan)
3551 {
3552 	struct ppc440spe_adma_chan *ppc440spe_chan;
3553 	struct ppc440spe_adma_desc_slot *iter, *_iter;
3554 	int in_use_descs = 0;
3555 
3556 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
3557 	ppc440spe_adma_slot_cleanup(ppc440spe_chan);
3558 
3559 	spin_lock_bh(&ppc440spe_chan->lock);
3560 	list_for_each_entry_safe(iter, _iter, &ppc440spe_chan->chain,
3561 					chain_node) {
3562 		in_use_descs++;
3563 		list_del(&iter->chain_node);
3564 	}
3565 	list_for_each_entry_safe_reverse(iter, _iter,
3566 			&ppc440spe_chan->all_slots, slot_node) {
3567 		list_del(&iter->slot_node);
3568 		kfree(iter);
3569 		ppc440spe_chan->slots_allocated--;
3570 	}
3571 	ppc440spe_chan->last_used = NULL;
3572 
3573 	dev_dbg(ppc440spe_chan->device->common.dev,
3574 		"ppc440spe adma%d %s slots_allocated %d\n",
3575 		ppc440spe_chan->device->id,
3576 		__func__, ppc440spe_chan->slots_allocated);
3577 	spin_unlock_bh(&ppc440spe_chan->lock);
3578 
3579 	/* one is ok since we left it on there on purpose */
3580 	if (in_use_descs > 1)
3581 		printk(KERN_ERR "SPE: Freeing %d in use descriptors!\n",
3582 			in_use_descs - 1);
3583 }
3584 
3585 /**
3586  * ppc440spe_adma_tx_status - poll the status of an ADMA transaction
3587  * @chan: ADMA channel handle
3588  * @cookie: ADMA transaction identifier
3589  * @txstate: a holder for the current state of the channel
3590  */
3591 static enum dma_status ppc440spe_adma_tx_status(struct dma_chan *chan,
3592 			dma_cookie_t cookie, struct dma_tx_state *txstate)
3593 {
3594 	struct ppc440spe_adma_chan *ppc440spe_chan;
3595 	enum dma_status ret;
3596 
3597 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
3598 	ret = dma_cookie_status(chan, cookie, txstate);
3599 	if (ret == DMA_COMPLETE)
3600 		return ret;
3601 
3602 	ppc440spe_adma_slot_cleanup(ppc440spe_chan);
3603 
3604 	return dma_cookie_status(chan, cookie, txstate);
3605 }
3606 
3607 /**
3608  * ppc440spe_adma_eot_handler - end of transfer interrupt handler
3609  */
3610 static irqreturn_t ppc440spe_adma_eot_handler(int irq, void *data)
3611 {
3612 	struct ppc440spe_adma_chan *chan = data;
3613 
3614 	dev_dbg(chan->device->common.dev,
3615 		"ppc440spe adma%d: %s\n", chan->device->id, __func__);
3616 
3617 	tasklet_schedule(&chan->irq_tasklet);
3618 	ppc440spe_adma_device_clear_eot_status(chan);
3619 
3620 	return IRQ_HANDLED;
3621 }
3622 
3623 /**
3624  * ppc440spe_adma_err_handler - DMA error interrupt handler;
3625  *	do the same things as a eot handler
3626  */
3627 static irqreturn_t ppc440spe_adma_err_handler(int irq, void *data)
3628 {
3629 	struct ppc440spe_adma_chan *chan = data;
3630 
3631 	dev_dbg(chan->device->common.dev,
3632 		"ppc440spe adma%d: %s\n", chan->device->id, __func__);
3633 
3634 	tasklet_schedule(&chan->irq_tasklet);
3635 	ppc440spe_adma_device_clear_eot_status(chan);
3636 
3637 	return IRQ_HANDLED;
3638 }
3639 
3640 /**
3641  * ppc440spe_test_callback - called when test operation has been done
3642  */
3643 static void ppc440spe_test_callback(void *unused)
3644 {
3645 	complete(&ppc440spe_r6_test_comp);
3646 }
3647 
3648 /**
3649  * ppc440spe_adma_issue_pending - flush all pending descriptors to h/w
3650  */
3651 static void ppc440spe_adma_issue_pending(struct dma_chan *chan)
3652 {
3653 	struct ppc440spe_adma_chan *ppc440spe_chan;
3654 
3655 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
3656 	dev_dbg(ppc440spe_chan->device->common.dev,
3657 		"ppc440spe adma%d: %s %d \n", ppc440spe_chan->device->id,
3658 		__func__, ppc440spe_chan->pending);
3659 
3660 	if (ppc440spe_chan->pending) {
3661 		ppc440spe_chan->pending = 0;
3662 		ppc440spe_chan_append(ppc440spe_chan);
3663 	}
3664 }
3665 
3666 /**
3667  * ppc440spe_chan_start_null_xor - initiate the first XOR operation (DMA engines
3668  *	use FIFOs (as opposite to chains used in XOR) so this is a XOR
3669  *	specific operation)
3670  */
3671 static void ppc440spe_chan_start_null_xor(struct ppc440spe_adma_chan *chan)
3672 {
3673 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
3674 	dma_cookie_t cookie;
3675 	int slot_cnt, slots_per_op;
3676 
3677 	dev_dbg(chan->device->common.dev,
3678 		"ppc440spe adma%d: %s\n", chan->device->id, __func__);
3679 
3680 	spin_lock_bh(&chan->lock);
3681 	slot_cnt = ppc440spe_chan_xor_slot_count(0, 2, &slots_per_op);
3682 	sw_desc = ppc440spe_adma_alloc_slots(chan, slot_cnt, slots_per_op);
3683 	if (sw_desc) {
3684 		group_start = sw_desc->group_head;
3685 		list_splice_init(&sw_desc->group_list, &chan->chain);
3686 		async_tx_ack(&sw_desc->async_tx);
3687 		ppc440spe_desc_init_null_xor(group_start);
3688 
3689 		cookie = dma_cookie_assign(&sw_desc->async_tx);
3690 
3691 		/* initialize the completed cookie to be less than
3692 		 * the most recently used cookie
3693 		 */
3694 		chan->common.completed_cookie = cookie - 1;
3695 
3696 		/* channel should not be busy */
3697 		BUG_ON(ppc440spe_chan_is_busy(chan));
3698 
3699 		/* set the descriptor address */
3700 		ppc440spe_chan_set_first_xor_descriptor(chan, sw_desc);
3701 
3702 		/* run the descriptor */
3703 		ppc440spe_chan_run(chan);
3704 	} else
3705 		printk(KERN_ERR "ppc440spe adma%d"
3706 			" failed to allocate null descriptor\n",
3707 			chan->device->id);
3708 	spin_unlock_bh(&chan->lock);
3709 }
3710 
3711 /**
3712  * ppc440spe_test_raid6 - test are RAID-6 capabilities enabled successfully.
3713  *	For this we just perform one WXOR operation with the same source
3714  *	and destination addresses, the GF-multiplier is 1; so if RAID-6
3715  *	capabilities are enabled then we'll get src/dst filled with zero.
3716  */
3717 static int ppc440spe_test_raid6(struct ppc440spe_adma_chan *chan)
3718 {
3719 	struct ppc440spe_adma_desc_slot *sw_desc, *iter;
3720 	struct page *pg;
3721 	char *a;
3722 	dma_addr_t dma_addr, addrs[2];
3723 	unsigned long op = 0;
3724 	int rval = 0;
3725 
3726 	set_bit(PPC440SPE_DESC_WXOR, &op);
3727 
3728 	pg = alloc_page(GFP_KERNEL);
3729 	if (!pg)
3730 		return -ENOMEM;
3731 
3732 	spin_lock_bh(&chan->lock);
3733 	sw_desc = ppc440spe_adma_alloc_slots(chan, 1, 1);
3734 	if (sw_desc) {
3735 		/* 1 src, 1 dsr, int_ena, WXOR */
3736 		ppc440spe_desc_init_dma01pq(sw_desc, 1, 1, 1, op);
3737 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
3738 			ppc440spe_desc_set_byte_count(iter, chan, PAGE_SIZE);
3739 			iter->unmap_len = PAGE_SIZE;
3740 		}
3741 	} else {
3742 		rval = -EFAULT;
3743 		spin_unlock_bh(&chan->lock);
3744 		goto exit;
3745 	}
3746 	spin_unlock_bh(&chan->lock);
3747 
3748 	/* Fill the test page with ones */
3749 	memset(page_address(pg), 0xFF, PAGE_SIZE);
3750 	dma_addr = dma_map_page(chan->device->dev, pg, 0,
3751 				PAGE_SIZE, DMA_BIDIRECTIONAL);
3752 
3753 	/* Setup addresses */
3754 	ppc440spe_adma_pq_set_src(sw_desc, dma_addr, 0);
3755 	ppc440spe_adma_pq_set_src_mult(sw_desc, 1, 0, 0);
3756 	addrs[0] = dma_addr;
3757 	addrs[1] = 0;
3758 	ppc440spe_adma_pq_set_dest(sw_desc, addrs, DMA_PREP_PQ_DISABLE_Q);
3759 
3760 	async_tx_ack(&sw_desc->async_tx);
3761 	sw_desc->async_tx.callback = ppc440spe_test_callback;
3762 	sw_desc->async_tx.callback_param = NULL;
3763 
3764 	init_completion(&ppc440spe_r6_test_comp);
3765 
3766 	ppc440spe_adma_tx_submit(&sw_desc->async_tx);
3767 	ppc440spe_adma_issue_pending(&chan->common);
3768 
3769 	wait_for_completion(&ppc440spe_r6_test_comp);
3770 
3771 	/* Now check if the test page is zeroed */
3772 	a = page_address(pg);
3773 	if ((*(u32 *)a) == 0 && memcmp(a, a+4, PAGE_SIZE-4) == 0) {
3774 		/* page is zero - RAID-6 enabled */
3775 		rval = 0;
3776 	} else {
3777 		/* RAID-6 was not enabled */
3778 		rval = -EINVAL;
3779 	}
3780 exit:
3781 	__free_page(pg);
3782 	return rval;
3783 }
3784 
3785 static void ppc440spe_adma_init_capabilities(struct ppc440spe_adma_device *adev)
3786 {
3787 	switch (adev->id) {
3788 	case PPC440SPE_DMA0_ID:
3789 	case PPC440SPE_DMA1_ID:
3790 		dma_cap_set(DMA_MEMCPY, adev->common.cap_mask);
3791 		dma_cap_set(DMA_INTERRUPT, adev->common.cap_mask);
3792 		dma_cap_set(DMA_PQ, adev->common.cap_mask);
3793 		dma_cap_set(DMA_PQ_VAL, adev->common.cap_mask);
3794 		dma_cap_set(DMA_XOR_VAL, adev->common.cap_mask);
3795 		break;
3796 	case PPC440SPE_XOR_ID:
3797 		dma_cap_set(DMA_XOR, adev->common.cap_mask);
3798 		dma_cap_set(DMA_PQ, adev->common.cap_mask);
3799 		dma_cap_set(DMA_INTERRUPT, adev->common.cap_mask);
3800 		adev->common.cap_mask = adev->common.cap_mask;
3801 		break;
3802 	}
3803 
3804 	/* Set base routines */
3805 	adev->common.device_alloc_chan_resources =
3806 				ppc440spe_adma_alloc_chan_resources;
3807 	adev->common.device_free_chan_resources =
3808 				ppc440spe_adma_free_chan_resources;
3809 	adev->common.device_tx_status = ppc440spe_adma_tx_status;
3810 	adev->common.device_issue_pending = ppc440spe_adma_issue_pending;
3811 
3812 	/* Set prep routines based on capability */
3813 	if (dma_has_cap(DMA_MEMCPY, adev->common.cap_mask)) {
3814 		adev->common.device_prep_dma_memcpy =
3815 			ppc440spe_adma_prep_dma_memcpy;
3816 	}
3817 	if (dma_has_cap(DMA_XOR, adev->common.cap_mask)) {
3818 		adev->common.max_xor = XOR_MAX_OPS;
3819 		adev->common.device_prep_dma_xor =
3820 			ppc440spe_adma_prep_dma_xor;
3821 	}
3822 	if (dma_has_cap(DMA_PQ, adev->common.cap_mask)) {
3823 		switch (adev->id) {
3824 		case PPC440SPE_DMA0_ID:
3825 			dma_set_maxpq(&adev->common,
3826 				DMA0_FIFO_SIZE / sizeof(struct dma_cdb), 0);
3827 			break;
3828 		case PPC440SPE_DMA1_ID:
3829 			dma_set_maxpq(&adev->common,
3830 				DMA1_FIFO_SIZE / sizeof(struct dma_cdb), 0);
3831 			break;
3832 		case PPC440SPE_XOR_ID:
3833 			adev->common.max_pq = XOR_MAX_OPS * 3;
3834 			break;
3835 		}
3836 		adev->common.device_prep_dma_pq =
3837 			ppc440spe_adma_prep_dma_pq;
3838 	}
3839 	if (dma_has_cap(DMA_PQ_VAL, adev->common.cap_mask)) {
3840 		switch (adev->id) {
3841 		case PPC440SPE_DMA0_ID:
3842 			adev->common.max_pq = DMA0_FIFO_SIZE /
3843 						sizeof(struct dma_cdb);
3844 			break;
3845 		case PPC440SPE_DMA1_ID:
3846 			adev->common.max_pq = DMA1_FIFO_SIZE /
3847 						sizeof(struct dma_cdb);
3848 			break;
3849 		}
3850 		adev->common.device_prep_dma_pq_val =
3851 			ppc440spe_adma_prep_dma_pqzero_sum;
3852 	}
3853 	if (dma_has_cap(DMA_XOR_VAL, adev->common.cap_mask)) {
3854 		switch (adev->id) {
3855 		case PPC440SPE_DMA0_ID:
3856 			adev->common.max_xor = DMA0_FIFO_SIZE /
3857 						sizeof(struct dma_cdb);
3858 			break;
3859 		case PPC440SPE_DMA1_ID:
3860 			adev->common.max_xor = DMA1_FIFO_SIZE /
3861 						sizeof(struct dma_cdb);
3862 			break;
3863 		}
3864 		adev->common.device_prep_dma_xor_val =
3865 			ppc440spe_adma_prep_dma_xor_zero_sum;
3866 	}
3867 	if (dma_has_cap(DMA_INTERRUPT, adev->common.cap_mask)) {
3868 		adev->common.device_prep_dma_interrupt =
3869 			ppc440spe_adma_prep_dma_interrupt;
3870 	}
3871 	pr_info("%s: AMCC(R) PPC440SP(E) ADMA Engine: "
3872 	  "( %s%s%s%s%s%s)\n",
3873 	  dev_name(adev->dev),
3874 	  dma_has_cap(DMA_PQ, adev->common.cap_mask) ? "pq " : "",
3875 	  dma_has_cap(DMA_PQ_VAL, adev->common.cap_mask) ? "pq_val " : "",
3876 	  dma_has_cap(DMA_XOR, adev->common.cap_mask) ? "xor " : "",
3877 	  dma_has_cap(DMA_XOR_VAL, adev->common.cap_mask) ? "xor_val " : "",
3878 	  dma_has_cap(DMA_MEMCPY, adev->common.cap_mask) ? "memcpy " : "",
3879 	  dma_has_cap(DMA_INTERRUPT, adev->common.cap_mask) ? "intr " : "");
3880 }
3881 
3882 static int ppc440spe_adma_setup_irqs(struct ppc440spe_adma_device *adev,
3883 				     struct ppc440spe_adma_chan *chan,
3884 				     int *initcode)
3885 {
3886 	struct platform_device *ofdev;
3887 	struct device_node *np;
3888 	int ret;
3889 
3890 	ofdev = container_of(adev->dev, struct platform_device, dev);
3891 	np = ofdev->dev.of_node;
3892 	if (adev->id != PPC440SPE_XOR_ID) {
3893 		adev->err_irq = irq_of_parse_and_map(np, 1);
3894 		if (adev->err_irq == NO_IRQ) {
3895 			dev_warn(adev->dev, "no err irq resource?\n");
3896 			*initcode = PPC_ADMA_INIT_IRQ2;
3897 			adev->err_irq = -ENXIO;
3898 		} else
3899 			atomic_inc(&ppc440spe_adma_err_irq_ref);
3900 	} else {
3901 		adev->err_irq = -ENXIO;
3902 	}
3903 
3904 	adev->irq = irq_of_parse_and_map(np, 0);
3905 	if (adev->irq == NO_IRQ) {
3906 		dev_err(adev->dev, "no irq resource\n");
3907 		*initcode = PPC_ADMA_INIT_IRQ1;
3908 		ret = -ENXIO;
3909 		goto err_irq_map;
3910 	}
3911 	dev_dbg(adev->dev, "irq %d, err irq %d\n",
3912 		adev->irq, adev->err_irq);
3913 
3914 	ret = request_irq(adev->irq, ppc440spe_adma_eot_handler,
3915 			  0, dev_driver_string(adev->dev), chan);
3916 	if (ret) {
3917 		dev_err(adev->dev, "can't request irq %d\n",
3918 			adev->irq);
3919 		*initcode = PPC_ADMA_INIT_IRQ1;
3920 		ret = -EIO;
3921 		goto err_req1;
3922 	}
3923 
3924 	/* only DMA engines have a separate error IRQ
3925 	 * so it's Ok if err_irq < 0 in XOR engine case.
3926 	 */
3927 	if (adev->err_irq > 0) {
3928 		/* both DMA engines share common error IRQ */
3929 		ret = request_irq(adev->err_irq,
3930 				  ppc440spe_adma_err_handler,
3931 				  IRQF_SHARED,
3932 				  dev_driver_string(adev->dev),
3933 				  chan);
3934 		if (ret) {
3935 			dev_err(adev->dev, "can't request irq %d\n",
3936 				adev->err_irq);
3937 			*initcode = PPC_ADMA_INIT_IRQ2;
3938 			ret = -EIO;
3939 			goto err_req2;
3940 		}
3941 	}
3942 
3943 	if (adev->id == PPC440SPE_XOR_ID) {
3944 		/* enable XOR engine interrupts */
3945 		iowrite32be(XOR_IE_CBCIE_BIT | XOR_IE_ICBIE_BIT |
3946 			    XOR_IE_ICIE_BIT | XOR_IE_RPTIE_BIT,
3947 			    &adev->xor_reg->ier);
3948 	} else {
3949 		u32 mask, enable;
3950 
3951 		np = of_find_compatible_node(NULL, NULL, "ibm,i2o-440spe");
3952 		if (!np) {
3953 			pr_err("%s: can't find I2O device tree node\n",
3954 				__func__);
3955 			ret = -ENODEV;
3956 			goto err_req2;
3957 		}
3958 		adev->i2o_reg = of_iomap(np, 0);
3959 		if (!adev->i2o_reg) {
3960 			pr_err("%s: failed to map I2O registers\n", __func__);
3961 			of_node_put(np);
3962 			ret = -EINVAL;
3963 			goto err_req2;
3964 		}
3965 		of_node_put(np);
3966 		/* Unmask 'CS FIFO Attention' interrupts and
3967 		 * enable generating interrupts on errors
3968 		 */
3969 		enable = (adev->id == PPC440SPE_DMA0_ID) ?
3970 			 ~(I2O_IOPIM_P0SNE | I2O_IOPIM_P0EM) :
3971 			 ~(I2O_IOPIM_P1SNE | I2O_IOPIM_P1EM);
3972 		mask = ioread32(&adev->i2o_reg->iopim) & enable;
3973 		iowrite32(mask, &adev->i2o_reg->iopim);
3974 	}
3975 	return 0;
3976 
3977 err_req2:
3978 	free_irq(adev->irq, chan);
3979 err_req1:
3980 	irq_dispose_mapping(adev->irq);
3981 err_irq_map:
3982 	if (adev->err_irq > 0) {
3983 		if (atomic_dec_and_test(&ppc440spe_adma_err_irq_ref))
3984 			irq_dispose_mapping(adev->err_irq);
3985 	}
3986 	return ret;
3987 }
3988 
3989 static void ppc440spe_adma_release_irqs(struct ppc440spe_adma_device *adev,
3990 					struct ppc440spe_adma_chan *chan)
3991 {
3992 	u32 mask, disable;
3993 
3994 	if (adev->id == PPC440SPE_XOR_ID) {
3995 		/* disable XOR engine interrupts */
3996 		mask = ioread32be(&adev->xor_reg->ier);
3997 		mask &= ~(XOR_IE_CBCIE_BIT | XOR_IE_ICBIE_BIT |
3998 			  XOR_IE_ICIE_BIT | XOR_IE_RPTIE_BIT);
3999 		iowrite32be(mask, &adev->xor_reg->ier);
4000 	} else {
4001 		/* disable DMAx engine interrupts */
4002 		disable = (adev->id == PPC440SPE_DMA0_ID) ?
4003 			  (I2O_IOPIM_P0SNE | I2O_IOPIM_P0EM) :
4004 			  (I2O_IOPIM_P1SNE | I2O_IOPIM_P1EM);
4005 		mask = ioread32(&adev->i2o_reg->iopim) | disable;
4006 		iowrite32(mask, &adev->i2o_reg->iopim);
4007 	}
4008 	free_irq(adev->irq, chan);
4009 	irq_dispose_mapping(adev->irq);
4010 	if (adev->err_irq > 0) {
4011 		free_irq(adev->err_irq, chan);
4012 		if (atomic_dec_and_test(&ppc440spe_adma_err_irq_ref)) {
4013 			irq_dispose_mapping(adev->err_irq);
4014 			iounmap(adev->i2o_reg);
4015 		}
4016 	}
4017 }
4018 
4019 /**
4020  * ppc440spe_adma_probe - probe the asynch device
4021  */
4022 static int ppc440spe_adma_probe(struct platform_device *ofdev)
4023 {
4024 	struct device_node *np = ofdev->dev.of_node;
4025 	struct resource res;
4026 	struct ppc440spe_adma_device *adev;
4027 	struct ppc440spe_adma_chan *chan;
4028 	struct ppc_dma_chan_ref *ref, *_ref;
4029 	int ret = 0, initcode = PPC_ADMA_INIT_OK;
4030 	const u32 *idx;
4031 	int len;
4032 	void *regs;
4033 	u32 id, pool_size;
4034 
4035 	if (of_device_is_compatible(np, "amcc,xor-accelerator")) {
4036 		id = PPC440SPE_XOR_ID;
4037 		/* As far as the XOR engine is concerned, it does not
4038 		 * use FIFOs but uses linked list. So there is no dependency
4039 		 * between pool size to allocate and the engine configuration.
4040 		 */
4041 		pool_size = PAGE_SIZE << 1;
4042 	} else {
4043 		/* it is DMA0 or DMA1 */
4044 		idx = of_get_property(np, "cell-index", &len);
4045 		if (!idx || (len != sizeof(u32))) {
4046 			dev_err(&ofdev->dev, "Device node %s has missing "
4047 				"or invalid cell-index property\n",
4048 				np->full_name);
4049 			return -EINVAL;
4050 		}
4051 		id = *idx;
4052 		/* DMA0,1 engines use FIFO to maintain CDBs, so we
4053 		 * should allocate the pool accordingly to size of this
4054 		 * FIFO. Thus, the pool size depends on the FIFO depth:
4055 		 * how much CDBs pointers the FIFO may contain then so
4056 		 * much CDBs we should provide in the pool.
4057 		 * That is
4058 		 *   CDB size = 32B;
4059 		 *   CDBs number = (DMA0_FIFO_SIZE >> 3);
4060 		 *   Pool size = CDBs number * CDB size =
4061 		 *      = (DMA0_FIFO_SIZE >> 3) << 5 = DMA0_FIFO_SIZE << 2.
4062 		 */
4063 		pool_size = (id == PPC440SPE_DMA0_ID) ?
4064 			    DMA0_FIFO_SIZE : DMA1_FIFO_SIZE;
4065 		pool_size <<= 2;
4066 	}
4067 
4068 	if (of_address_to_resource(np, 0, &res)) {
4069 		dev_err(&ofdev->dev, "failed to get memory resource\n");
4070 		initcode = PPC_ADMA_INIT_MEMRES;
4071 		ret = -ENODEV;
4072 		goto out;
4073 	}
4074 
4075 	if (!request_mem_region(res.start, resource_size(&res),
4076 				dev_driver_string(&ofdev->dev))) {
4077 		dev_err(&ofdev->dev, "failed to request memory region %pR\n",
4078 			&res);
4079 		initcode = PPC_ADMA_INIT_MEMREG;
4080 		ret = -EBUSY;
4081 		goto out;
4082 	}
4083 
4084 	/* create a device */
4085 	adev = kzalloc(sizeof(*adev), GFP_KERNEL);
4086 	if (!adev) {
4087 		dev_err(&ofdev->dev, "failed to allocate device\n");
4088 		initcode = PPC_ADMA_INIT_ALLOC;
4089 		ret = -ENOMEM;
4090 		goto err_adev_alloc;
4091 	}
4092 
4093 	adev->id = id;
4094 	adev->pool_size = pool_size;
4095 	/* allocate coherent memory for hardware descriptors */
4096 	adev->dma_desc_pool_virt = dma_alloc_coherent(&ofdev->dev,
4097 					adev->pool_size, &adev->dma_desc_pool,
4098 					GFP_KERNEL);
4099 	if (adev->dma_desc_pool_virt == NULL) {
4100 		dev_err(&ofdev->dev, "failed to allocate %d bytes of coherent "
4101 			"memory for hardware descriptors\n",
4102 			adev->pool_size);
4103 		initcode = PPC_ADMA_INIT_COHERENT;
4104 		ret = -ENOMEM;
4105 		goto err_dma_alloc;
4106 	}
4107 	dev_dbg(&ofdev->dev, "allocated descriptor pool virt 0x%p phys 0x%llx\n",
4108 		adev->dma_desc_pool_virt, (u64)adev->dma_desc_pool);
4109 
4110 	regs = ioremap(res.start, resource_size(&res));
4111 	if (!regs) {
4112 		dev_err(&ofdev->dev, "failed to ioremap regs!\n");
4113 		ret = -ENOMEM;
4114 		goto err_regs_alloc;
4115 	}
4116 
4117 	if (adev->id == PPC440SPE_XOR_ID) {
4118 		adev->xor_reg = regs;
4119 		/* Reset XOR */
4120 		iowrite32be(XOR_CRSR_XASR_BIT, &adev->xor_reg->crsr);
4121 		iowrite32be(XOR_CRSR_64BA_BIT, &adev->xor_reg->crrr);
4122 	} else {
4123 		size_t fifo_size = (adev->id == PPC440SPE_DMA0_ID) ?
4124 				   DMA0_FIFO_SIZE : DMA1_FIFO_SIZE;
4125 		adev->dma_reg = regs;
4126 		/* DMAx_FIFO_SIZE is defined in bytes,
4127 		 * <fsiz> - is defined in number of CDB pointers (8byte).
4128 		 * DMA FIFO Length = CSlength + CPlength, where
4129 		 * CSlength = CPlength = (fsiz + 1) * 8.
4130 		 */
4131 		iowrite32(DMA_FIFO_ENABLE | ((fifo_size >> 3) - 2),
4132 			  &adev->dma_reg->fsiz);
4133 		/* Configure DMA engine */
4134 		iowrite32(DMA_CFG_DXEPR_HP | DMA_CFG_DFMPP_HP | DMA_CFG_FALGN,
4135 			  &adev->dma_reg->cfg);
4136 		/* Clear Status */
4137 		iowrite32(~0, &adev->dma_reg->dsts);
4138 	}
4139 
4140 	adev->dev = &ofdev->dev;
4141 	adev->common.dev = &ofdev->dev;
4142 	INIT_LIST_HEAD(&adev->common.channels);
4143 	platform_set_drvdata(ofdev, adev);
4144 
4145 	/* create a channel */
4146 	chan = kzalloc(sizeof(*chan), GFP_KERNEL);
4147 	if (!chan) {
4148 		dev_err(&ofdev->dev, "can't allocate channel structure\n");
4149 		initcode = PPC_ADMA_INIT_CHANNEL;
4150 		ret = -ENOMEM;
4151 		goto err_chan_alloc;
4152 	}
4153 
4154 	spin_lock_init(&chan->lock);
4155 	INIT_LIST_HEAD(&chan->chain);
4156 	INIT_LIST_HEAD(&chan->all_slots);
4157 	chan->device = adev;
4158 	chan->common.device = &adev->common;
4159 	dma_cookie_init(&chan->common);
4160 	list_add_tail(&chan->common.device_node, &adev->common.channels);
4161 	tasklet_init(&chan->irq_tasklet, ppc440spe_adma_tasklet,
4162 		     (unsigned long)chan);
4163 
4164 	/* allocate and map helper pages for async validation or
4165 	 * async_mult/async_sum_product operations on DMA0/1.
4166 	 */
4167 	if (adev->id != PPC440SPE_XOR_ID) {
4168 		chan->pdest_page = alloc_page(GFP_KERNEL);
4169 		chan->qdest_page = alloc_page(GFP_KERNEL);
4170 		if (!chan->pdest_page ||
4171 		    !chan->qdest_page) {
4172 			if (chan->pdest_page)
4173 				__free_page(chan->pdest_page);
4174 			if (chan->qdest_page)
4175 				__free_page(chan->qdest_page);
4176 			ret = -ENOMEM;
4177 			goto err_page_alloc;
4178 		}
4179 		chan->pdest = dma_map_page(&ofdev->dev, chan->pdest_page, 0,
4180 					   PAGE_SIZE, DMA_BIDIRECTIONAL);
4181 		chan->qdest = dma_map_page(&ofdev->dev, chan->qdest_page, 0,
4182 					   PAGE_SIZE, DMA_BIDIRECTIONAL);
4183 	}
4184 
4185 	ref = kmalloc(sizeof(*ref), GFP_KERNEL);
4186 	if (ref) {
4187 		ref->chan = &chan->common;
4188 		INIT_LIST_HEAD(&ref->node);
4189 		list_add_tail(&ref->node, &ppc440spe_adma_chan_list);
4190 	} else {
4191 		dev_err(&ofdev->dev, "failed to allocate channel reference!\n");
4192 		ret = -ENOMEM;
4193 		goto err_ref_alloc;
4194 	}
4195 
4196 	ret = ppc440spe_adma_setup_irqs(adev, chan, &initcode);
4197 	if (ret)
4198 		goto err_irq;
4199 
4200 	ppc440spe_adma_init_capabilities(adev);
4201 
4202 	ret = dma_async_device_register(&adev->common);
4203 	if (ret) {
4204 		initcode = PPC_ADMA_INIT_REGISTER;
4205 		dev_err(&ofdev->dev, "failed to register dma device\n");
4206 		goto err_dev_reg;
4207 	}
4208 
4209 	goto out;
4210 
4211 err_dev_reg:
4212 	ppc440spe_adma_release_irqs(adev, chan);
4213 err_irq:
4214 	list_for_each_entry_safe(ref, _ref, &ppc440spe_adma_chan_list, node) {
4215 		if (chan == to_ppc440spe_adma_chan(ref->chan)) {
4216 			list_del(&ref->node);
4217 			kfree(ref);
4218 		}
4219 	}
4220 err_ref_alloc:
4221 	if (adev->id != PPC440SPE_XOR_ID) {
4222 		dma_unmap_page(&ofdev->dev, chan->pdest,
4223 			       PAGE_SIZE, DMA_BIDIRECTIONAL);
4224 		dma_unmap_page(&ofdev->dev, chan->qdest,
4225 			       PAGE_SIZE, DMA_BIDIRECTIONAL);
4226 		__free_page(chan->pdest_page);
4227 		__free_page(chan->qdest_page);
4228 	}
4229 err_page_alloc:
4230 	kfree(chan);
4231 err_chan_alloc:
4232 	if (adev->id == PPC440SPE_XOR_ID)
4233 		iounmap(adev->xor_reg);
4234 	else
4235 		iounmap(adev->dma_reg);
4236 err_regs_alloc:
4237 	dma_free_coherent(adev->dev, adev->pool_size,
4238 			  adev->dma_desc_pool_virt,
4239 			  adev->dma_desc_pool);
4240 err_dma_alloc:
4241 	kfree(adev);
4242 err_adev_alloc:
4243 	release_mem_region(res.start, resource_size(&res));
4244 out:
4245 	if (id < PPC440SPE_ADMA_ENGINES_NUM)
4246 		ppc440spe_adma_devices[id] = initcode;
4247 
4248 	return ret;
4249 }
4250 
4251 /**
4252  * ppc440spe_adma_remove - remove the asynch device
4253  */
4254 static int ppc440spe_adma_remove(struct platform_device *ofdev)
4255 {
4256 	struct ppc440spe_adma_device *adev = platform_get_drvdata(ofdev);
4257 	struct device_node *np = ofdev->dev.of_node;
4258 	struct resource res;
4259 	struct dma_chan *chan, *_chan;
4260 	struct ppc_dma_chan_ref *ref, *_ref;
4261 	struct ppc440spe_adma_chan *ppc440spe_chan;
4262 
4263 	if (adev->id < PPC440SPE_ADMA_ENGINES_NUM)
4264 		ppc440spe_adma_devices[adev->id] = -1;
4265 
4266 	dma_async_device_unregister(&adev->common);
4267 
4268 	list_for_each_entry_safe(chan, _chan, &adev->common.channels,
4269 				 device_node) {
4270 		ppc440spe_chan = to_ppc440spe_adma_chan(chan);
4271 		ppc440spe_adma_release_irqs(adev, ppc440spe_chan);
4272 		tasklet_kill(&ppc440spe_chan->irq_tasklet);
4273 		if (adev->id != PPC440SPE_XOR_ID) {
4274 			dma_unmap_page(&ofdev->dev, ppc440spe_chan->pdest,
4275 					PAGE_SIZE, DMA_BIDIRECTIONAL);
4276 			dma_unmap_page(&ofdev->dev, ppc440spe_chan->qdest,
4277 					PAGE_SIZE, DMA_BIDIRECTIONAL);
4278 			__free_page(ppc440spe_chan->pdest_page);
4279 			__free_page(ppc440spe_chan->qdest_page);
4280 		}
4281 		list_for_each_entry_safe(ref, _ref, &ppc440spe_adma_chan_list,
4282 					 node) {
4283 			if (ppc440spe_chan ==
4284 			    to_ppc440spe_adma_chan(ref->chan)) {
4285 				list_del(&ref->node);
4286 				kfree(ref);
4287 			}
4288 		}
4289 		list_del(&chan->device_node);
4290 		kfree(ppc440spe_chan);
4291 	}
4292 
4293 	dma_free_coherent(adev->dev, adev->pool_size,
4294 			  adev->dma_desc_pool_virt, adev->dma_desc_pool);
4295 	if (adev->id == PPC440SPE_XOR_ID)
4296 		iounmap(adev->xor_reg);
4297 	else
4298 		iounmap(adev->dma_reg);
4299 	of_address_to_resource(np, 0, &res);
4300 	release_mem_region(res.start, resource_size(&res));
4301 	kfree(adev);
4302 	return 0;
4303 }
4304 
4305 /*
4306  * /sys driver interface to enable h/w RAID-6 capabilities
4307  * Files created in e.g. /sys/devices/plb.0/400100100.dma0/driver/
4308  * directory are "devices", "enable" and "poly".
4309  * "devices" shows available engines.
4310  * "enable" is used to enable RAID-6 capabilities or to check
4311  * whether these has been activated.
4312  * "poly" allows setting/checking used polynomial (for PPC440SPe only).
4313  */
4314 
4315 static ssize_t show_ppc440spe_devices(struct device_driver *dev, char *buf)
4316 {
4317 	ssize_t size = 0;
4318 	int i;
4319 
4320 	for (i = 0; i < PPC440SPE_ADMA_ENGINES_NUM; i++) {
4321 		if (ppc440spe_adma_devices[i] == -1)
4322 			continue;
4323 		size += snprintf(buf + size, PAGE_SIZE - size,
4324 				 "PPC440SP(E)-ADMA.%d: %s\n", i,
4325 				 ppc_adma_errors[ppc440spe_adma_devices[i]]);
4326 	}
4327 	return size;
4328 }
4329 
4330 static ssize_t show_ppc440spe_r6enable(struct device_driver *dev, char *buf)
4331 {
4332 	return snprintf(buf, PAGE_SIZE,
4333 			"PPC440SP(e) RAID-6 capabilities are %sABLED.\n",
4334 			ppc440spe_r6_enabled ? "EN" : "DIS");
4335 }
4336 
4337 static ssize_t store_ppc440spe_r6enable(struct device_driver *dev,
4338 					const char *buf, size_t count)
4339 {
4340 	unsigned long val;
4341 
4342 	if (!count || count > 11)
4343 		return -EINVAL;
4344 
4345 	if (!ppc440spe_r6_tchan)
4346 		return -EFAULT;
4347 
4348 	/* Write a key */
4349 	sscanf(buf, "%lx", &val);
4350 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_XORBA, val);
4351 	isync();
4352 
4353 	/* Verify whether it really works now */
4354 	if (ppc440spe_test_raid6(ppc440spe_r6_tchan) == 0) {
4355 		pr_info("PPC440SP(e) RAID-6 has been activated "
4356 			"successfully\n");
4357 		ppc440spe_r6_enabled = 1;
4358 	} else {
4359 		pr_info("PPC440SP(e) RAID-6 hasn't been activated!"
4360 			" Error key ?\n");
4361 		ppc440spe_r6_enabled = 0;
4362 	}
4363 	return count;
4364 }
4365 
4366 static ssize_t show_ppc440spe_r6poly(struct device_driver *dev, char *buf)
4367 {
4368 	ssize_t size = 0;
4369 	u32 reg;
4370 
4371 #ifdef CONFIG_440SP
4372 	/* 440SP has fixed polynomial */
4373 	reg = 0x4d;
4374 #else
4375 	reg = dcr_read(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL);
4376 	reg >>= MQ0_CFBHL_POLY;
4377 	reg &= 0xFF;
4378 #endif
4379 
4380 	size = snprintf(buf, PAGE_SIZE, "PPC440SP(e) RAID-6 driver "
4381 			"uses 0x1%02x polynomial.\n", reg);
4382 	return size;
4383 }
4384 
4385 static ssize_t store_ppc440spe_r6poly(struct device_driver *dev,
4386 				      const char *buf, size_t count)
4387 {
4388 	unsigned long reg, val;
4389 
4390 #ifdef CONFIG_440SP
4391 	/* 440SP uses default 0x14D polynomial only */
4392 	return -EINVAL;
4393 #endif
4394 
4395 	if (!count || count > 6)
4396 		return -EINVAL;
4397 
4398 	/* e.g., 0x14D or 0x11D */
4399 	sscanf(buf, "%lx", &val);
4400 
4401 	if (val & ~0x1FF)
4402 		return -EINVAL;
4403 
4404 	val &= 0xFF;
4405 	reg = dcr_read(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL);
4406 	reg &= ~(0xFF << MQ0_CFBHL_POLY);
4407 	reg |= val << MQ0_CFBHL_POLY;
4408 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL, reg);
4409 
4410 	return count;
4411 }
4412 
4413 static DRIVER_ATTR(devices, S_IRUGO, show_ppc440spe_devices, NULL);
4414 static DRIVER_ATTR(enable, S_IRUGO | S_IWUSR, show_ppc440spe_r6enable,
4415 		   store_ppc440spe_r6enable);
4416 static DRIVER_ATTR(poly, S_IRUGO | S_IWUSR, show_ppc440spe_r6poly,
4417 		   store_ppc440spe_r6poly);
4418 
4419 /*
4420  * Common initialisation for RAID engines; allocate memory for
4421  * DMAx FIFOs, perform configuration common for all DMA engines.
4422  * Further DMA engine specific configuration is done at probe time.
4423  */
4424 static int ppc440spe_configure_raid_devices(void)
4425 {
4426 	struct device_node *np;
4427 	struct resource i2o_res;
4428 	struct i2o_regs __iomem *i2o_reg;
4429 	dcr_host_t i2o_dcr_host;
4430 	unsigned int dcr_base, dcr_len;
4431 	int i, ret;
4432 
4433 	np = of_find_compatible_node(NULL, NULL, "ibm,i2o-440spe");
4434 	if (!np) {
4435 		pr_err("%s: can't find I2O device tree node\n",
4436 			__func__);
4437 		return -ENODEV;
4438 	}
4439 
4440 	if (of_address_to_resource(np, 0, &i2o_res)) {
4441 		of_node_put(np);
4442 		return -EINVAL;
4443 	}
4444 
4445 	i2o_reg = of_iomap(np, 0);
4446 	if (!i2o_reg) {
4447 		pr_err("%s: failed to map I2O registers\n", __func__);
4448 		of_node_put(np);
4449 		return -EINVAL;
4450 	}
4451 
4452 	/* Get I2O DCRs base */
4453 	dcr_base = dcr_resource_start(np, 0);
4454 	dcr_len = dcr_resource_len(np, 0);
4455 	if (!dcr_base && !dcr_len) {
4456 		pr_err("%s: can't get DCR registers base/len!\n",
4457 			np->full_name);
4458 		of_node_put(np);
4459 		iounmap(i2o_reg);
4460 		return -ENODEV;
4461 	}
4462 
4463 	i2o_dcr_host = dcr_map(np, dcr_base, dcr_len);
4464 	if (!DCR_MAP_OK(i2o_dcr_host)) {
4465 		pr_err("%s: failed to map DCRs!\n", np->full_name);
4466 		of_node_put(np);
4467 		iounmap(i2o_reg);
4468 		return -ENODEV;
4469 	}
4470 	of_node_put(np);
4471 
4472 	/* Provide memory regions for DMA's FIFOs: I2O, DMA0 and DMA1 share
4473 	 * the base address of FIFO memory space.
4474 	 * Actually we need twice more physical memory than programmed in the
4475 	 * <fsiz> register (because there are two FIFOs for each DMA: CP and CS)
4476 	 */
4477 	ppc440spe_dma_fifo_buf = kmalloc((DMA0_FIFO_SIZE + DMA1_FIFO_SIZE) << 1,
4478 					 GFP_KERNEL);
4479 	if (!ppc440spe_dma_fifo_buf) {
4480 		pr_err("%s: DMA FIFO buffer allocation failed.\n", __func__);
4481 		iounmap(i2o_reg);
4482 		dcr_unmap(i2o_dcr_host, dcr_len);
4483 		return -ENOMEM;
4484 	}
4485 
4486 	/*
4487 	 * Configure h/w
4488 	 */
4489 	/* Reset I2O/DMA */
4490 	mtdcri(SDR0, DCRN_SDR0_SRST, DCRN_SDR0_SRST_I2ODMA);
4491 	mtdcri(SDR0, DCRN_SDR0_SRST, 0);
4492 
4493 	/* Setup the base address of mmaped registers */
4494 	dcr_write(i2o_dcr_host, DCRN_I2O0_IBAH, (u32)(i2o_res.start >> 32));
4495 	dcr_write(i2o_dcr_host, DCRN_I2O0_IBAL, (u32)(i2o_res.start) |
4496 						I2O_REG_ENABLE);
4497 	dcr_unmap(i2o_dcr_host, dcr_len);
4498 
4499 	/* Setup FIFO memory space base address */
4500 	iowrite32(0, &i2o_reg->ifbah);
4501 	iowrite32(((u32)__pa(ppc440spe_dma_fifo_buf)), &i2o_reg->ifbal);
4502 
4503 	/* set zero FIFO size for I2O, so the whole
4504 	 * ppc440spe_dma_fifo_buf is used by DMAs.
4505 	 * DMAx_FIFOs will be configured while probe.
4506 	 */
4507 	iowrite32(0, &i2o_reg->ifsiz);
4508 	iounmap(i2o_reg);
4509 
4510 	/* To prepare WXOR/RXOR functionality we need access to
4511 	 * Memory Queue Module DCRs (finally it will be enabled
4512 	 * via /sys interface of the ppc440spe ADMA driver).
4513 	 */
4514 	np = of_find_compatible_node(NULL, NULL, "ibm,mq-440spe");
4515 	if (!np) {
4516 		pr_err("%s: can't find MQ device tree node\n",
4517 			__func__);
4518 		ret = -ENODEV;
4519 		goto out_free;
4520 	}
4521 
4522 	/* Get MQ DCRs base */
4523 	dcr_base = dcr_resource_start(np, 0);
4524 	dcr_len = dcr_resource_len(np, 0);
4525 	if (!dcr_base && !dcr_len) {
4526 		pr_err("%s: can't get DCR registers base/len!\n",
4527 			np->full_name);
4528 		ret = -ENODEV;
4529 		goto out_mq;
4530 	}
4531 
4532 	ppc440spe_mq_dcr_host = dcr_map(np, dcr_base, dcr_len);
4533 	if (!DCR_MAP_OK(ppc440spe_mq_dcr_host)) {
4534 		pr_err("%s: failed to map DCRs!\n", np->full_name);
4535 		ret = -ENODEV;
4536 		goto out_mq;
4537 	}
4538 	of_node_put(np);
4539 	ppc440spe_mq_dcr_len = dcr_len;
4540 
4541 	/* Set HB alias */
4542 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_BAUH, DMA_CUED_XOR_HB);
4543 
4544 	/* Set:
4545 	 * - LL transaction passing limit to 1;
4546 	 * - Memory controller cycle limit to 1;
4547 	 * - Galois Polynomial to 0x14d (default)
4548 	 */
4549 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL,
4550 		  (1 << MQ0_CFBHL_TPLM) | (1 << MQ0_CFBHL_HBCL) |
4551 		  (PPC440SPE_DEFAULT_POLY << MQ0_CFBHL_POLY));
4552 
4553 	atomic_set(&ppc440spe_adma_err_irq_ref, 0);
4554 	for (i = 0; i < PPC440SPE_ADMA_ENGINES_NUM; i++)
4555 		ppc440spe_adma_devices[i] = -1;
4556 
4557 	return 0;
4558 
4559 out_mq:
4560 	of_node_put(np);
4561 out_free:
4562 	kfree(ppc440spe_dma_fifo_buf);
4563 	return ret;
4564 }
4565 
4566 static const struct of_device_id ppc440spe_adma_of_match[] = {
4567 	{ .compatible	= "ibm,dma-440spe", },
4568 	{ .compatible	= "amcc,xor-accelerator", },
4569 	{},
4570 };
4571 MODULE_DEVICE_TABLE(of, ppc440spe_adma_of_match);
4572 
4573 static struct platform_driver ppc440spe_adma_driver = {
4574 	.probe = ppc440spe_adma_probe,
4575 	.remove = ppc440spe_adma_remove,
4576 	.driver = {
4577 		.name = "PPC440SP(E)-ADMA",
4578 		.of_match_table = ppc440spe_adma_of_match,
4579 	},
4580 };
4581 
4582 static __init int ppc440spe_adma_init(void)
4583 {
4584 	int ret;
4585 
4586 	ret = ppc440spe_configure_raid_devices();
4587 	if (ret)
4588 		return ret;
4589 
4590 	ret = platform_driver_register(&ppc440spe_adma_driver);
4591 	if (ret) {
4592 		pr_err("%s: failed to register platform driver\n",
4593 			__func__);
4594 		goto out_reg;
4595 	}
4596 
4597 	/* Initialization status */
4598 	ret = driver_create_file(&ppc440spe_adma_driver.driver,
4599 				 &driver_attr_devices);
4600 	if (ret)
4601 		goto out_dev;
4602 
4603 	/* RAID-6 h/w enable entry */
4604 	ret = driver_create_file(&ppc440spe_adma_driver.driver,
4605 				 &driver_attr_enable);
4606 	if (ret)
4607 		goto out_en;
4608 
4609 	/* GF polynomial to use */
4610 	ret = driver_create_file(&ppc440spe_adma_driver.driver,
4611 				 &driver_attr_poly);
4612 	if (!ret)
4613 		return ret;
4614 
4615 	driver_remove_file(&ppc440spe_adma_driver.driver,
4616 			   &driver_attr_enable);
4617 out_en:
4618 	driver_remove_file(&ppc440spe_adma_driver.driver,
4619 			   &driver_attr_devices);
4620 out_dev:
4621 	/* User will not be able to enable h/w RAID-6 */
4622 	pr_err("%s: failed to create RAID-6 driver interface\n",
4623 		__func__);
4624 	platform_driver_unregister(&ppc440spe_adma_driver);
4625 out_reg:
4626 	dcr_unmap(ppc440spe_mq_dcr_host, ppc440spe_mq_dcr_len);
4627 	kfree(ppc440spe_dma_fifo_buf);
4628 	return ret;
4629 }
4630 
4631 static void __exit ppc440spe_adma_exit(void)
4632 {
4633 	driver_remove_file(&ppc440spe_adma_driver.driver,
4634 			   &driver_attr_poly);
4635 	driver_remove_file(&ppc440spe_adma_driver.driver,
4636 			   &driver_attr_enable);
4637 	driver_remove_file(&ppc440spe_adma_driver.driver,
4638 			   &driver_attr_devices);
4639 	platform_driver_unregister(&ppc440spe_adma_driver);
4640 	dcr_unmap(ppc440spe_mq_dcr_host, ppc440spe_mq_dcr_len);
4641 	kfree(ppc440spe_dma_fifo_buf);
4642 }
4643 
4644 arch_initcall(ppc440spe_adma_init);
4645 module_exit(ppc440spe_adma_exit);
4646 
4647 MODULE_AUTHOR("Yuri Tikhonov <yur@emcraft.com>");
4648 MODULE_DESCRIPTION("PPC440SPE ADMA Engine Driver");
4649 MODULE_LICENSE("GPL");
4650