xref: /linux/drivers/dma/fsl_raid.c (revision 66498c75b4f8017f62d720d9b59675bdf3abce91)
1 /*
2  * drivers/dma/fsl_raid.c
3  *
4  * Freescale RAID Engine device driver
5  *
6  * Author:
7  *	Harninder Rai <harninder.rai@freescale.com>
8  *	Naveen Burmi <naveenburmi@freescale.com>
9  *
10  * Rewrite:
11  *	Xuelin Shi <xuelin.shi@freescale.com>
12  *
13  * Copyright (c) 2010-2014 Freescale Semiconductor, Inc.
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions are met:
17  *     * Redistributions of source code must retain the above copyright
18  *       notice, this list of conditions and the following disclaimer.
19  *     * Redistributions in binary form must reproduce the above copyright
20  *       notice, this list of conditions and the following disclaimer in the
21  *       documentation and/or other materials provided with the distribution.
22  *     * Neither the name of Freescale Semiconductor nor the
23  *       names of its contributors may be used to endorse or promote products
24  *       derived from this software without specific prior written permission.
25  *
26  * ALTERNATIVELY, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") as published by the Free Software
28  * Foundation, either version 2 of that License or (at your option) any
29  * later version.
30  *
31  * THIS SOFTWARE IS PROVIDED BY Freescale Semiconductor ``AS IS'' AND ANY
32  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
33  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
34  * DISCLAIMED. IN NO EVENT SHALL Freescale Semiconductor BE LIABLE FOR ANY
35  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
36  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
37  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
38  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
39  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
40  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
41  *
42  * Theory of operation:
43  *
44  * General capabilities:
45  *	RAID Engine (RE) block is capable of offloading XOR, memcpy and P/Q
46  *	calculations required in RAID5 and RAID6 operations. RE driver
47  *	registers with Linux's ASYNC layer as dma driver. RE hardware
48  *	maintains strict ordering of the requests through chained
49  *	command queueing.
50  *
51  * Data flow:
52  *	Software RAID layer of Linux (MD layer) maintains RAID partitions,
53  *	strips, stripes etc. It sends requests to the underlying ASYNC layer
54  *	which further passes it to RE driver. ASYNC layer decides which request
55  *	goes to which job ring of RE hardware. For every request processed by
56  *	RAID Engine, driver gets an interrupt unless coalescing is set. The
57  *	per job ring interrupt handler checks the status register for errors,
58  *	clears the interrupt and leave the post interrupt processing to the irq
59  *	thread.
60  */
61 #include <linux/interrupt.h>
62 #include <linux/module.h>
63 #include <linux/of.h>
64 #include <linux/of_irq.h>
65 #include <linux/of_platform.h>
66 #include <linux/platform_device.h>
67 #include <linux/dma-mapping.h>
68 #include <linux/dmapool.h>
69 #include <linux/dmaengine.h>
70 #include <linux/io.h>
71 #include <linux/spinlock.h>
72 #include <linux/slab.h>
73 
74 #include "dmaengine.h"
75 #include "fsl_raid.h"
76 
77 #define FSL_RE_MAX_XOR_SRCS	16
78 #define FSL_RE_MAX_PQ_SRCS	16
79 #define FSL_RE_MIN_DESCS	256
80 #define FSL_RE_MAX_DESCS	(4 * FSL_RE_MIN_DESCS)
81 #define FSL_RE_FRAME_FORMAT	0x1
82 #define FSL_RE_MAX_DATA_LEN	(1024*1024)
83 
84 #define to_fsl_re_dma_desc(tx) container_of(tx, struct fsl_re_desc, async_tx)
85 
86 /* Add descriptors into per chan software queue - submit_q */
fsl_re_tx_submit(struct dma_async_tx_descriptor * tx)87 static dma_cookie_t fsl_re_tx_submit(struct dma_async_tx_descriptor *tx)
88 {
89 	struct fsl_re_desc *desc;
90 	struct fsl_re_chan *re_chan;
91 	dma_cookie_t cookie;
92 	unsigned long flags;
93 
94 	desc = to_fsl_re_dma_desc(tx);
95 	re_chan = container_of(tx->chan, struct fsl_re_chan, chan);
96 
97 	spin_lock_irqsave(&re_chan->desc_lock, flags);
98 	cookie = dma_cookie_assign(tx);
99 	list_add_tail(&desc->node, &re_chan->submit_q);
100 	spin_unlock_irqrestore(&re_chan->desc_lock, flags);
101 
102 	return cookie;
103 }
104 
105 /* Copy descriptor from per chan software queue into hardware job ring */
fsl_re_issue_pending(struct dma_chan * chan)106 static void fsl_re_issue_pending(struct dma_chan *chan)
107 {
108 	struct fsl_re_chan *re_chan;
109 	int avail;
110 	struct fsl_re_desc *desc, *_desc;
111 	unsigned long flags;
112 
113 	re_chan = container_of(chan, struct fsl_re_chan, chan);
114 
115 	spin_lock_irqsave(&re_chan->desc_lock, flags);
116 	avail = FSL_RE_SLOT_AVAIL(
117 		in_be32(&re_chan->jrregs->inbring_slot_avail));
118 
119 	list_for_each_entry_safe(desc, _desc, &re_chan->submit_q, node) {
120 		if (!avail)
121 			break;
122 
123 		list_move_tail(&desc->node, &re_chan->active_q);
124 
125 		memcpy(&re_chan->inb_ring_virt_addr[re_chan->inb_count],
126 		       &desc->hwdesc, sizeof(struct fsl_re_hw_desc));
127 
128 		re_chan->inb_count = (re_chan->inb_count + 1) &
129 						FSL_RE_RING_SIZE_MASK;
130 		out_be32(&re_chan->jrregs->inbring_add_job, FSL_RE_ADD_JOB(1));
131 		avail--;
132 	}
133 	spin_unlock_irqrestore(&re_chan->desc_lock, flags);
134 }
135 
fsl_re_desc_done(struct fsl_re_desc * desc)136 static void fsl_re_desc_done(struct fsl_re_desc *desc)
137 {
138 	dma_cookie_complete(&desc->async_tx);
139 	dma_descriptor_unmap(&desc->async_tx);
140 	dmaengine_desc_get_callback_invoke(&desc->async_tx, NULL);
141 }
142 
fsl_re_cleanup_descs(struct fsl_re_chan * re_chan)143 static void fsl_re_cleanup_descs(struct fsl_re_chan *re_chan)
144 {
145 	struct fsl_re_desc *desc, *_desc;
146 	unsigned long flags;
147 
148 	spin_lock_irqsave(&re_chan->desc_lock, flags);
149 	list_for_each_entry_safe(desc, _desc, &re_chan->ack_q, node) {
150 		if (async_tx_test_ack(&desc->async_tx))
151 			list_move_tail(&desc->node, &re_chan->free_q);
152 	}
153 	spin_unlock_irqrestore(&re_chan->desc_lock, flags);
154 
155 	fsl_re_issue_pending(&re_chan->chan);
156 }
157 
fsl_re_dequeue(struct tasklet_struct * t)158 static void fsl_re_dequeue(struct tasklet_struct *t)
159 {
160 	struct fsl_re_chan *re_chan = from_tasklet(re_chan, t, irqtask);
161 	struct fsl_re_desc *desc, *_desc;
162 	struct fsl_re_hw_desc *hwdesc;
163 	unsigned long flags;
164 	unsigned int count, oub_count;
165 	int found;
166 
167 	fsl_re_cleanup_descs(re_chan);
168 
169 	spin_lock_irqsave(&re_chan->desc_lock, flags);
170 	count =	FSL_RE_SLOT_FULL(in_be32(&re_chan->jrregs->oubring_slot_full));
171 	while (count--) {
172 		found = 0;
173 		hwdesc = &re_chan->oub_ring_virt_addr[re_chan->oub_count];
174 		list_for_each_entry_safe(desc, _desc, &re_chan->active_q,
175 					 node) {
176 			/* compare the hw dma addr to find the completed */
177 			if (desc->hwdesc.lbea32 == hwdesc->lbea32 &&
178 			    desc->hwdesc.addr_low == hwdesc->addr_low) {
179 				found = 1;
180 				break;
181 			}
182 		}
183 
184 		if (found) {
185 			fsl_re_desc_done(desc);
186 			list_move_tail(&desc->node, &re_chan->ack_q);
187 		} else {
188 			dev_err(re_chan->dev,
189 				"found hwdesc not in sw queue, discard it\n");
190 		}
191 
192 		oub_count = (re_chan->oub_count + 1) & FSL_RE_RING_SIZE_MASK;
193 		re_chan->oub_count = oub_count;
194 
195 		out_be32(&re_chan->jrregs->oubring_job_rmvd,
196 			 FSL_RE_RMVD_JOB(1));
197 	}
198 	spin_unlock_irqrestore(&re_chan->desc_lock, flags);
199 }
200 
201 /* Per Job Ring interrupt handler */
fsl_re_isr(int irq,void * data)202 static irqreturn_t fsl_re_isr(int irq, void *data)
203 {
204 	struct fsl_re_chan *re_chan;
205 	u32 irqstate, status;
206 
207 	re_chan = dev_get_drvdata((struct device *)data);
208 
209 	irqstate = in_be32(&re_chan->jrregs->jr_interrupt_status);
210 	if (!irqstate)
211 		return IRQ_NONE;
212 
213 	/*
214 	 * There's no way in upper layer (read MD layer) to recover from
215 	 * error conditions except restart everything. In long term we
216 	 * need to do something more than just crashing
217 	 */
218 	if (irqstate & FSL_RE_ERROR) {
219 		status = in_be32(&re_chan->jrregs->jr_status);
220 		dev_err(re_chan->dev, "chan error irqstate: %x, status: %x\n",
221 			irqstate, status);
222 	}
223 
224 	/* Clear interrupt */
225 	out_be32(&re_chan->jrregs->jr_interrupt_status, FSL_RE_CLR_INTR);
226 
227 	tasklet_schedule(&re_chan->irqtask);
228 
229 	return IRQ_HANDLED;
230 }
231 
fsl_re_tx_status(struct dma_chan * chan,dma_cookie_t cookie,struct dma_tx_state * txstate)232 static enum dma_status fsl_re_tx_status(struct dma_chan *chan,
233 					dma_cookie_t cookie,
234 					struct dma_tx_state *txstate)
235 {
236 	return dma_cookie_status(chan, cookie, txstate);
237 }
238 
fill_cfd_frame(struct fsl_re_cmpnd_frame * cf,u8 index,size_t length,dma_addr_t addr,bool final)239 static void fill_cfd_frame(struct fsl_re_cmpnd_frame *cf, u8 index,
240 			   size_t length, dma_addr_t addr, bool final)
241 {
242 	u32 efrl = length & FSL_RE_CF_LENGTH_MASK;
243 
244 	efrl |= final << FSL_RE_CF_FINAL_SHIFT;
245 	cf[index].efrl32 = cpu_to_be32(efrl);
246 	cf[index].addr_high = cpu_to_be32(upper_32_bits(addr));
247 	cf[index].addr_low = cpu_to_be32(lower_32_bits(addr));
248 }
249 
fsl_re_init_desc(struct fsl_re_chan * re_chan,struct fsl_re_desc * desc,void * cf,dma_addr_t paddr)250 static struct fsl_re_desc *fsl_re_init_desc(struct fsl_re_chan *re_chan,
251 					    struct fsl_re_desc *desc,
252 					    void *cf, dma_addr_t paddr)
253 {
254 	desc->re_chan = re_chan;
255 	desc->async_tx.tx_submit = fsl_re_tx_submit;
256 	dma_async_tx_descriptor_init(&desc->async_tx, &re_chan->chan);
257 	INIT_LIST_HEAD(&desc->node);
258 
259 	desc->hwdesc.fmt32 = cpu_to_be32(FSL_RE_FRAME_FORMAT <<
260 					  FSL_RE_HWDESC_FMT_SHIFT);
261 	desc->hwdesc.lbea32 = cpu_to_be32(upper_32_bits(paddr));
262 	desc->hwdesc.addr_low = cpu_to_be32(lower_32_bits(paddr));
263 	desc->cf_addr = cf;
264 	desc->cf_paddr = paddr;
265 
266 	desc->cdb_addr = (void *)(cf + FSL_RE_CF_DESC_SIZE);
267 	desc->cdb_paddr = paddr + FSL_RE_CF_DESC_SIZE;
268 
269 	return desc;
270 }
271 
fsl_re_chan_alloc_desc(struct fsl_re_chan * re_chan,unsigned long flags)272 static struct fsl_re_desc *fsl_re_chan_alloc_desc(struct fsl_re_chan *re_chan,
273 						  unsigned long flags)
274 {
275 	struct fsl_re_desc *desc = NULL;
276 	void *cf;
277 	dma_addr_t paddr;
278 	unsigned long lock_flag;
279 
280 	fsl_re_cleanup_descs(re_chan);
281 
282 	spin_lock_irqsave(&re_chan->desc_lock, lock_flag);
283 	if (!list_empty(&re_chan->free_q)) {
284 		/* take one desc from free_q */
285 		desc = list_first_entry(&re_chan->free_q,
286 					struct fsl_re_desc, node);
287 		list_del(&desc->node);
288 
289 		desc->async_tx.flags = flags;
290 	}
291 	spin_unlock_irqrestore(&re_chan->desc_lock, lock_flag);
292 
293 	if (!desc) {
294 		desc = kzalloc_obj(*desc, GFP_NOWAIT);
295 		if (!desc)
296 			return NULL;
297 
298 		cf = dma_pool_alloc(re_chan->re_dev->cf_desc_pool, GFP_NOWAIT,
299 				    &paddr);
300 		if (!cf) {
301 			kfree(desc);
302 			return NULL;
303 		}
304 
305 		desc = fsl_re_init_desc(re_chan, desc, cf, paddr);
306 		desc->async_tx.flags = flags;
307 
308 		spin_lock_irqsave(&re_chan->desc_lock, lock_flag);
309 		re_chan->alloc_count++;
310 		spin_unlock_irqrestore(&re_chan->desc_lock, lock_flag);
311 	}
312 
313 	return desc;
314 }
315 
fsl_re_prep_dma_genq(struct dma_chan * chan,dma_addr_t dest,dma_addr_t * src,unsigned int src_cnt,const unsigned char * scf,size_t len,unsigned long flags)316 static struct dma_async_tx_descriptor *fsl_re_prep_dma_genq(
317 		struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
318 		unsigned int src_cnt, const unsigned char *scf, size_t len,
319 		unsigned long flags)
320 {
321 	struct fsl_re_chan *re_chan;
322 	struct fsl_re_desc *desc;
323 	struct fsl_re_xor_cdb *xor;
324 	struct fsl_re_cmpnd_frame *cf;
325 	u32 cdb;
326 	unsigned int i, j;
327 	unsigned int save_src_cnt = src_cnt;
328 	int cont_q = 0;
329 
330 	re_chan = container_of(chan, struct fsl_re_chan, chan);
331 	if (len > FSL_RE_MAX_DATA_LEN) {
332 		dev_err(re_chan->dev, "genq tx length %zu, max length %d\n",
333 			len, FSL_RE_MAX_DATA_LEN);
334 		return NULL;
335 	}
336 
337 	desc = fsl_re_chan_alloc_desc(re_chan, flags);
338 	if (desc <= 0)
339 		return NULL;
340 
341 	if (scf && (flags & DMA_PREP_CONTINUE)) {
342 		cont_q = 1;
343 		src_cnt += 1;
344 	}
345 
346 	/* Filling xor CDB */
347 	cdb = FSL_RE_XOR_OPCODE << FSL_RE_CDB_OPCODE_SHIFT;
348 	cdb |= (src_cnt - 1) << FSL_RE_CDB_NRCS_SHIFT;
349 	cdb |= FSL_RE_BLOCK_SIZE << FSL_RE_CDB_BLKSIZE_SHIFT;
350 	cdb |= FSL_RE_INTR_ON_ERROR << FSL_RE_CDB_ERROR_SHIFT;
351 	cdb |= FSL_RE_DATA_DEP << FSL_RE_CDB_DEPEND_SHIFT;
352 	xor = desc->cdb_addr;
353 	xor->cdb32 = cdb;
354 
355 	if (scf) {
356 		/* compute q = src0*coef0^src1*coef1^..., * is GF(8) mult */
357 		for (i = 0; i < save_src_cnt; i++)
358 			xor->gfm[i] = scf[i];
359 		if (cont_q)
360 			xor->gfm[i++] = 1;
361 	} else {
362 		/* compute P, that is XOR all srcs */
363 		for (i = 0; i < src_cnt; i++)
364 			xor->gfm[i] = 1;
365 	}
366 
367 	/* Filling frame 0 of compound frame descriptor with CDB */
368 	cf = desc->cf_addr;
369 	fill_cfd_frame(cf, 0, sizeof(*xor), desc->cdb_paddr, 0);
370 
371 	/* Fill CFD's 1st frame with dest buffer */
372 	fill_cfd_frame(cf, 1, len, dest, 0);
373 
374 	/* Fill CFD's rest of the frames with source buffers */
375 	for (i = 2, j = 0; j < save_src_cnt; i++, j++)
376 		fill_cfd_frame(cf, i, len, src[j], 0);
377 
378 	/* Fill the last frame and mark it final */
379 	if (cont_q)
380 		fill_cfd_frame(cf, i, len, dest, 1);
381 	else
382 		fill_cfd_frame(cf, i - 1, len, src[j - 1], 1);
383 
384 	return &desc->async_tx;
385 }
386 
387 /*
388  * Prep function for P parity calculation.In RAID Engine terminology,
389  * XOR calculation is called GenQ calculation done through GenQ command
390  */
fsl_re_prep_dma_xor(struct dma_chan * chan,dma_addr_t dest,dma_addr_t * src,unsigned int src_cnt,size_t len,unsigned long flags)391 static struct dma_async_tx_descriptor *fsl_re_prep_dma_xor(
392 		struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
393 		unsigned int src_cnt, size_t len, unsigned long flags)
394 {
395 	/* NULL let genq take all coef as 1 */
396 	return fsl_re_prep_dma_genq(chan, dest, src, src_cnt, NULL, len, flags);
397 }
398 
399 /*
400  * Prep function for P/Q parity calculation.In RAID Engine terminology,
401  * P/Q calculation is called GenQQ done through GenQQ command
402  */
fsl_re_prep_dma_pq(struct dma_chan * chan,dma_addr_t * dest,dma_addr_t * src,unsigned int src_cnt,const unsigned char * scf,size_t len,unsigned long flags)403 static struct dma_async_tx_descriptor *fsl_re_prep_dma_pq(
404 		struct dma_chan *chan, dma_addr_t *dest, dma_addr_t *src,
405 		unsigned int src_cnt, const unsigned char *scf, size_t len,
406 		unsigned long flags)
407 {
408 	struct fsl_re_chan *re_chan;
409 	struct fsl_re_desc *desc;
410 	struct fsl_re_pq_cdb *pq;
411 	struct fsl_re_cmpnd_frame *cf;
412 	u32 cdb;
413 	u8 *p;
414 	int gfmq_len, i, j;
415 	unsigned int save_src_cnt = src_cnt;
416 
417 	re_chan = container_of(chan, struct fsl_re_chan, chan);
418 	if (len > FSL_RE_MAX_DATA_LEN) {
419 		dev_err(re_chan->dev, "pq tx length is %zu, max length is %d\n",
420 			len, FSL_RE_MAX_DATA_LEN);
421 		return NULL;
422 	}
423 
424 	/*
425 	 * RE requires at least 2 sources, if given only one source, we pass the
426 	 * second source same as the first one.
427 	 * With only one source, generating P is meaningless, only generate Q.
428 	 */
429 	if (src_cnt == 1) {
430 		struct dma_async_tx_descriptor *tx;
431 		dma_addr_t dma_src[2];
432 		unsigned char coef[2];
433 
434 		dma_src[0] = *src;
435 		coef[0] = *scf;
436 		dma_src[1] = *src;
437 		coef[1] = 0;
438 		tx = fsl_re_prep_dma_genq(chan, dest[1], dma_src, 2, coef, len,
439 					  flags);
440 		if (tx)
441 			desc = to_fsl_re_dma_desc(tx);
442 
443 		return tx;
444 	}
445 
446 	/*
447 	 * During RAID6 array creation, Linux's MD layer gets P and Q
448 	 * calculated separately in two steps. But our RAID Engine has
449 	 * the capability to calculate both P and Q with a single command
450 	 * Hence to merge well with MD layer, we need to provide a hook
451 	 * here and call re_jq_prep_dma_genq() function
452 	 */
453 
454 	if (flags & DMA_PREP_PQ_DISABLE_P)
455 		return fsl_re_prep_dma_genq(chan, dest[1], src, src_cnt,
456 				scf, len, flags);
457 
458 	if (flags & DMA_PREP_CONTINUE)
459 		src_cnt += 3;
460 
461 	desc = fsl_re_chan_alloc_desc(re_chan, flags);
462 	if (desc <= 0)
463 		return NULL;
464 
465 	/* Filling GenQQ CDB */
466 	cdb = FSL_RE_PQ_OPCODE << FSL_RE_CDB_OPCODE_SHIFT;
467 	cdb |= (src_cnt - 1) << FSL_RE_CDB_NRCS_SHIFT;
468 	cdb |= FSL_RE_BLOCK_SIZE << FSL_RE_CDB_BLKSIZE_SHIFT;
469 	cdb |= FSL_RE_BUFFER_OUTPUT << FSL_RE_CDB_BUFFER_SHIFT;
470 	cdb |= FSL_RE_DATA_DEP << FSL_RE_CDB_DEPEND_SHIFT;
471 
472 	pq = desc->cdb_addr;
473 	pq->cdb32 = cdb;
474 
475 	p = pq->gfm_q1;
476 	/* Init gfm_q1[] */
477 	for (i = 0; i < src_cnt; i++)
478 		p[i] = 1;
479 
480 	/* Align gfm[] to 32bit */
481 	gfmq_len = ALIGN(src_cnt, 4);
482 
483 	/* Init gfm_q2[] */
484 	p += gfmq_len;
485 	for (i = 0; i < src_cnt; i++)
486 		p[i] = scf[i];
487 
488 	/* Filling frame 0 of compound frame descriptor with CDB */
489 	cf = desc->cf_addr;
490 	fill_cfd_frame(cf, 0, sizeof(struct fsl_re_pq_cdb), desc->cdb_paddr, 0);
491 
492 	/* Fill CFD's 1st & 2nd frame with dest buffers */
493 	for (i = 1, j = 0; i < 3; i++, j++)
494 		fill_cfd_frame(cf, i, len, dest[j], 0);
495 
496 	/* Fill CFD's rest of the frames with source buffers */
497 	for (i = 3, j = 0; j < save_src_cnt; i++, j++)
498 		fill_cfd_frame(cf, i, len, src[j], 0);
499 
500 	/* PQ computation continuation */
501 	if (flags & DMA_PREP_CONTINUE) {
502 		if (src_cnt - save_src_cnt == 3) {
503 			p[save_src_cnt] = 0;
504 			p[save_src_cnt + 1] = 0;
505 			p[save_src_cnt + 2] = 1;
506 			fill_cfd_frame(cf, i++, len, dest[0], 0);
507 			fill_cfd_frame(cf, i++, len, dest[1], 0);
508 			fill_cfd_frame(cf, i++, len, dest[1], 1);
509 		} else {
510 			dev_err(re_chan->dev, "PQ tx continuation error!\n");
511 			return NULL;
512 		}
513 	} else {
514 		/* Mark the last source buffer frame final */
515 		fill_cfd_frame(cf, i - 1, len, src[j - 1], 1);
516 	}
517 
518 	return &desc->async_tx;
519 }
520 
521 /*
522  * Prep function for memcpy. In RAID Engine, memcpy is done through MOVE
523  * command. Logic of this function will need to be modified once multipage
524  * support is added in Linux's MD/ASYNC Layer
525  */
fsl_re_prep_dma_memcpy(struct dma_chan * chan,dma_addr_t dest,dma_addr_t src,size_t len,unsigned long flags)526 static struct dma_async_tx_descriptor *fsl_re_prep_dma_memcpy(
527 		struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
528 		size_t len, unsigned long flags)
529 {
530 	struct fsl_re_chan *re_chan;
531 	struct fsl_re_desc *desc;
532 	size_t length;
533 	struct fsl_re_cmpnd_frame *cf;
534 	struct fsl_re_move_cdb *move;
535 	u32 cdb;
536 
537 	re_chan = container_of(chan, struct fsl_re_chan, chan);
538 
539 	if (len > FSL_RE_MAX_DATA_LEN) {
540 		dev_err(re_chan->dev, "cp tx length is %zu, max length is %d\n",
541 			len, FSL_RE_MAX_DATA_LEN);
542 		return NULL;
543 	}
544 
545 	desc = fsl_re_chan_alloc_desc(re_chan, flags);
546 	if (desc <= 0)
547 		return NULL;
548 
549 	/* Filling move CDB */
550 	cdb = FSL_RE_MOVE_OPCODE << FSL_RE_CDB_OPCODE_SHIFT;
551 	cdb |= FSL_RE_BLOCK_SIZE << FSL_RE_CDB_BLKSIZE_SHIFT;
552 	cdb |= FSL_RE_INTR_ON_ERROR << FSL_RE_CDB_ERROR_SHIFT;
553 	cdb |= FSL_RE_DATA_DEP << FSL_RE_CDB_DEPEND_SHIFT;
554 
555 	move = desc->cdb_addr;
556 	move->cdb32 = cdb;
557 
558 	/* Filling frame 0 of CFD with move CDB */
559 	cf = desc->cf_addr;
560 	fill_cfd_frame(cf, 0, sizeof(*move), desc->cdb_paddr, 0);
561 
562 	length = min_t(size_t, len, FSL_RE_MAX_DATA_LEN);
563 
564 	/* Fill CFD's 1st frame with dest buffer */
565 	fill_cfd_frame(cf, 1, length, dest, 0);
566 
567 	/* Fill CFD's 2nd frame with src buffer */
568 	fill_cfd_frame(cf, 2, length, src, 1);
569 
570 	return &desc->async_tx;
571 }
572 
fsl_re_alloc_chan_resources(struct dma_chan * chan)573 static int fsl_re_alloc_chan_resources(struct dma_chan *chan)
574 {
575 	struct fsl_re_chan *re_chan;
576 	struct fsl_re_desc *desc;
577 	void *cf;
578 	dma_addr_t paddr;
579 	int i;
580 
581 	re_chan = container_of(chan, struct fsl_re_chan, chan);
582 	for (i = 0; i < FSL_RE_MIN_DESCS; i++) {
583 		desc = kzalloc_obj(*desc);
584 		if (!desc)
585 			break;
586 
587 		cf = dma_pool_alloc(re_chan->re_dev->cf_desc_pool, GFP_KERNEL,
588 				    &paddr);
589 		if (!cf) {
590 			kfree(desc);
591 			break;
592 		}
593 
594 		INIT_LIST_HEAD(&desc->node);
595 		fsl_re_init_desc(re_chan, desc, cf, paddr);
596 
597 		list_add_tail(&desc->node, &re_chan->free_q);
598 		re_chan->alloc_count++;
599 	}
600 	return re_chan->alloc_count;
601 }
602 
fsl_re_free_chan_resources(struct dma_chan * chan)603 static void fsl_re_free_chan_resources(struct dma_chan *chan)
604 {
605 	struct fsl_re_chan *re_chan;
606 	struct fsl_re_desc *desc;
607 
608 	re_chan = container_of(chan, struct fsl_re_chan, chan);
609 	while (re_chan->alloc_count--) {
610 		desc = list_first_entry(&re_chan->free_q,
611 					struct fsl_re_desc,
612 					node);
613 
614 		list_del(&desc->node);
615 		dma_pool_free(re_chan->re_dev->cf_desc_pool, desc->cf_addr,
616 			      desc->cf_paddr);
617 		kfree(desc);
618 	}
619 
620 	if (!list_empty(&re_chan->free_q))
621 		dev_err(re_chan->dev, "chan resource cannot be cleaned!\n");
622 }
623 
fsl_re_chan_probe(struct platform_device * ofdev,struct device_node * np,u8 q,u32 off)624 static int fsl_re_chan_probe(struct platform_device *ofdev,
625 		      struct device_node *np, u8 q, u32 off)
626 {
627 	struct device *dev, *chandev;
628 	struct fsl_re_drv_private *re_priv;
629 	struct fsl_re_chan *chan;
630 	struct dma_device *dma_dev;
631 	u32 ptr;
632 	u32 status;
633 	int ret = 0, rc;
634 	struct platform_device *chan_ofdev;
635 
636 	dev = &ofdev->dev;
637 	re_priv = dev_get_drvdata(dev);
638 	dma_dev = &re_priv->dma_dev;
639 
640 	chan = devm_kzalloc(dev, sizeof(*chan), GFP_KERNEL);
641 	if (!chan)
642 		return -ENOMEM;
643 
644 	/* create platform device for chan node */
645 	chan_ofdev = of_platform_device_create(np, NULL, dev);
646 	if (!chan_ofdev) {
647 		dev_err(dev, "Not able to create ofdev for jr %d\n", q);
648 		ret = -EINVAL;
649 		goto err_free;
650 	}
651 
652 	/* read reg property from dts */
653 	rc = of_property_read_u32(np, "reg", &ptr);
654 	if (rc) {
655 		dev_err(dev, "Reg property not found in jr %d\n", q);
656 		ret = -ENODEV;
657 		goto err_free;
658 	}
659 
660 	chan->jrregs = re_priv->base + off + ptr;
661 
662 	/* read irq property from dts */
663 	chan->irq = irq_of_parse_and_map(np, 0);
664 	if (!chan->irq) {
665 		dev_err(dev, "No IRQ defined for JR %d\n", q);
666 		ret = -ENODEV;
667 		goto err_free;
668 	}
669 
670 	snprintf(chan->name, sizeof(chan->name), "re_jr%02d", q);
671 
672 	chandev = &chan_ofdev->dev;
673 	tasklet_setup(&chan->irqtask, fsl_re_dequeue);
674 
675 	ret = request_irq(chan->irq, fsl_re_isr, 0, chan->name, chandev);
676 	if (ret) {
677 		dev_err(dev, "Unable to register interrupt for JR %d\n", q);
678 		ret = -EINVAL;
679 		goto err_free;
680 	}
681 
682 	re_priv->re_jrs[q] = chan;
683 	chan->chan.device = dma_dev;
684 	chan->chan.private = chan;
685 	chan->dev = chandev;
686 	chan->re_dev = re_priv;
687 
688 	spin_lock_init(&chan->desc_lock);
689 	INIT_LIST_HEAD(&chan->ack_q);
690 	INIT_LIST_HEAD(&chan->active_q);
691 	INIT_LIST_HEAD(&chan->submit_q);
692 	INIT_LIST_HEAD(&chan->free_q);
693 
694 	chan->inb_ring_virt_addr = dma_pool_alloc(chan->re_dev->hw_desc_pool,
695 		GFP_KERNEL, &chan->inb_phys_addr);
696 	if (!chan->inb_ring_virt_addr) {
697 		dev_err(dev, "No dma memory for inb_ring_virt_addr\n");
698 		ret = -ENOMEM;
699 		goto err_free;
700 	}
701 
702 	chan->oub_ring_virt_addr = dma_pool_alloc(chan->re_dev->hw_desc_pool,
703 		GFP_KERNEL, &chan->oub_phys_addr);
704 	if (!chan->oub_ring_virt_addr) {
705 		dev_err(dev, "No dma memory for oub_ring_virt_addr\n");
706 		ret = -ENOMEM;
707 		goto err_free_1;
708 	}
709 
710 	/* Program the Inbound/Outbound ring base addresses and size */
711 	out_be32(&chan->jrregs->inbring_base_h,
712 		 chan->inb_phys_addr & FSL_RE_ADDR_BIT_MASK);
713 	out_be32(&chan->jrregs->oubring_base_h,
714 		 chan->oub_phys_addr & FSL_RE_ADDR_BIT_MASK);
715 	out_be32(&chan->jrregs->inbring_base_l,
716 		 chan->inb_phys_addr >> FSL_RE_ADDR_BIT_SHIFT);
717 	out_be32(&chan->jrregs->oubring_base_l,
718 		 chan->oub_phys_addr >> FSL_RE_ADDR_BIT_SHIFT);
719 	out_be32(&chan->jrregs->inbring_size,
720 		 FSL_RE_RING_SIZE << FSL_RE_RING_SIZE_SHIFT);
721 	out_be32(&chan->jrregs->oubring_size,
722 		 FSL_RE_RING_SIZE << FSL_RE_RING_SIZE_SHIFT);
723 
724 	/* Read LIODN value from u-boot */
725 	status = in_be32(&chan->jrregs->jr_config_1) & FSL_RE_REG_LIODN_MASK;
726 
727 	/* Program the CFG reg */
728 	out_be32(&chan->jrregs->jr_config_1,
729 		 FSL_RE_CFG1_CBSI | FSL_RE_CFG1_CBS0 | status);
730 
731 	dev_set_drvdata(chandev, chan);
732 
733 	/* Enable RE/CHAN */
734 	out_be32(&chan->jrregs->jr_command, FSL_RE_ENABLE);
735 
736 	return 0;
737 
738 err_free_1:
739 	dma_pool_free(chan->re_dev->hw_desc_pool, chan->inb_ring_virt_addr,
740 		      chan->inb_phys_addr);
741 err_free:
742 	return ret;
743 }
744 
745 /* Probe function for RAID Engine */
fsl_re_probe(struct platform_device * ofdev)746 static int fsl_re_probe(struct platform_device *ofdev)
747 {
748 	struct fsl_re_ctrl __iomem *re_regs;
749 	struct fsl_re_drv_private *re_priv;
750 	struct device_node *child;
751 	u32 off;
752 	u8 ridx = 0;
753 	struct dma_device *dma_dev;
754 	int rc;
755 	struct device *dev = &ofdev->dev;
756 
757 	/* IOMAP the entire RAID Engine region */
758 	re_regs = devm_platform_ioremap_resource(ofdev, 0);
759 	if (IS_ERR(re_regs))
760 		return PTR_ERR(re_regs);
761 
762 	re_priv = devm_kzalloc(dev, sizeof(*re_priv), GFP_KERNEL);
763 	if (!re_priv)
764 		return -ENOMEM;
765 
766 	re_priv->base = re_regs;
767 
768 	/* Program the RE mode */
769 	out_be32(&re_regs->global_config, FSL_RE_NON_DPAA_MODE);
770 
771 	/* Program Galois Field polynomial */
772 	out_be32(&re_regs->galois_field_config, FSL_RE_GFM_POLY);
773 
774 	dev_info(dev, "version %x, mode %x, gfp %x\n",
775 		 in_be32(&re_regs->re_version_id),
776 		 in_be32(&re_regs->global_config),
777 		 in_be32(&re_regs->galois_field_config));
778 
779 	dma_dev = &re_priv->dma_dev;
780 	dma_dev->dev = dev;
781 	INIT_LIST_HEAD(&dma_dev->channels);
782 	dma_set_mask(dev, DMA_BIT_MASK(40));
783 
784 	dma_dev->device_alloc_chan_resources = fsl_re_alloc_chan_resources;
785 	dma_dev->device_tx_status = fsl_re_tx_status;
786 	dma_dev->device_issue_pending = fsl_re_issue_pending;
787 
788 	dma_dev->max_xor = FSL_RE_MAX_XOR_SRCS;
789 	dma_dev->device_prep_dma_xor = fsl_re_prep_dma_xor;
790 	dma_cap_set(DMA_XOR, dma_dev->cap_mask);
791 
792 	dma_dev->max_pq = FSL_RE_MAX_PQ_SRCS;
793 	dma_dev->device_prep_dma_pq = fsl_re_prep_dma_pq;
794 	dma_cap_set(DMA_PQ, dma_dev->cap_mask);
795 
796 	dma_dev->device_prep_dma_memcpy = fsl_re_prep_dma_memcpy;
797 	dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask);
798 
799 	dma_dev->device_free_chan_resources = fsl_re_free_chan_resources;
800 
801 	re_priv->total_chans = 0;
802 
803 	re_priv->cf_desc_pool = dmam_pool_create("fsl_re_cf_desc_pool", dev,
804 					FSL_RE_CF_CDB_SIZE,
805 					FSL_RE_CF_CDB_ALIGN, 0);
806 
807 	if (!re_priv->cf_desc_pool) {
808 		dev_err(dev, "No memory for fsl re_cf desc pool\n");
809 		return -ENOMEM;
810 	}
811 
812 	re_priv->hw_desc_pool = dmam_pool_create("fsl_re_hw_desc_pool", dev,
813 			sizeof(struct fsl_re_hw_desc) * FSL_RE_RING_SIZE,
814 			FSL_RE_FRAME_ALIGN, 0);
815 	if (!re_priv->hw_desc_pool) {
816 		dev_err(dev, "No memory for fsl re_hw desc pool\n");
817 		return -ENOMEM;
818 	}
819 
820 	dev_set_drvdata(dev, re_priv);
821 
822 	/* Parse Device tree to find out the total number of JQs present */
823 	for_each_compatible_node_scoped(np, NULL, "fsl,raideng-v1.0-job-queue") {
824 		rc = of_property_read_u32(np, "reg", &off);
825 		if (rc) {
826 			dev_err(dev, "Reg property not found in JQ node\n");
827 			return -ENODEV;
828 		}
829 		/* Find out the Job Rings present under each JQ */
830 		for_each_child_of_node(np, child) {
831 			rc = of_device_is_compatible(child,
832 					     "fsl,raideng-v1.0-job-ring");
833 			if (rc) {
834 				fsl_re_chan_probe(ofdev, child, ridx++, off);
835 				re_priv->total_chans++;
836 			}
837 		}
838 	}
839 
840 	dma_async_device_register(dma_dev);
841 
842 	return 0;
843 }
844 
fsl_re_remove_chan(struct fsl_re_chan * chan)845 static void fsl_re_remove_chan(struct fsl_re_chan *chan)
846 {
847 	tasklet_kill(&chan->irqtask);
848 
849 	dma_pool_free(chan->re_dev->hw_desc_pool, chan->inb_ring_virt_addr,
850 		      chan->inb_phys_addr);
851 
852 	dma_pool_free(chan->re_dev->hw_desc_pool, chan->oub_ring_virt_addr,
853 		      chan->oub_phys_addr);
854 }
855 
fsl_re_remove(struct platform_device * ofdev)856 static void fsl_re_remove(struct platform_device *ofdev)
857 {
858 	struct fsl_re_drv_private *re_priv;
859 	struct device *dev;
860 	int i;
861 
862 	dev = &ofdev->dev;
863 	re_priv = dev_get_drvdata(dev);
864 
865 	/* Cleanup chan related memory areas */
866 	for (i = 0; i < re_priv->total_chans; i++)
867 		fsl_re_remove_chan(re_priv->re_jrs[i]);
868 
869 	/* Unregister the driver */
870 	dma_async_device_unregister(&re_priv->dma_dev);
871 }
872 
873 static const struct of_device_id fsl_re_ids[] = {
874 	{ .compatible = "fsl,raideng-v1.0", },
875 	{}
876 };
877 MODULE_DEVICE_TABLE(of, fsl_re_ids);
878 
879 static struct platform_driver fsl_re_driver = {
880 	.driver = {
881 		.name = "fsl-raideng",
882 		.of_match_table = fsl_re_ids,
883 	},
884 	.probe = fsl_re_probe,
885 	.remove = fsl_re_remove,
886 };
887 
888 module_platform_driver(fsl_re_driver);
889 
890 MODULE_AUTHOR("Harninder Rai <harninder.rai@freescale.com>");
891 MODULE_LICENSE("GPL v2");
892 MODULE_DESCRIPTION("Freescale RAID Engine Device Driver");
893