xref: /linux/drivers/dma/amba-pl08x.c (revision 80d443e8876602be2c130f79c4de81e12e2a700d)
1 /*
2  * Copyright (c) 2006 ARM Ltd.
3  * Copyright (c) 2010 ST-Ericsson SA
4  *
5  * Author: Peter Pearse <peter.pearse@arm.com>
6  * Author: Linus Walleij <linus.walleij@stericsson.com>
7  *
8  * This program is free software; you can redistribute it and/or modify it
9  * under the terms of the GNU General Public License as published by the Free
10  * Software Foundation; either version 2 of the License, or (at your option)
11  * any later version.
12  *
13  * This program is distributed in the hope that it will be useful, but WITHOUT
14  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
15  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
16  * more details.
17  *
18  * The full GNU General Public License is in this distribution in the file
19  * called COPYING.
20  *
21  * Documentation: ARM DDI 0196G == PL080
22  * Documentation: ARM DDI 0218E == PL081
23  * Documentation: S3C6410 User's Manual == PL080S
24  *
25  * PL080 & PL081 both have 16 sets of DMA signals that can be routed to any
26  * channel.
27  *
28  * The PL080 has 8 channels available for simultaneous use, and the PL081
29  * has only two channels. So on these DMA controllers the number of channels
30  * and the number of incoming DMA signals are two totally different things.
31  * It is usually not possible to theoretically handle all physical signals,
32  * so a multiplexing scheme with possible denial of use is necessary.
33  *
34  * The PL080 has a dual bus master, PL081 has a single master.
35  *
36  * PL080S is a version modified by Samsung and used in S3C64xx SoCs.
37  * It differs in following aspects:
38  * - CH_CONFIG register at different offset,
39  * - separate CH_CONTROL2 register for transfer size,
40  * - bigger maximum transfer size,
41  * - 8-word aligned LLI, instead of 4-word, due to extra CCTL2 word,
42  * - no support for peripheral flow control.
43  *
44  * Memory to peripheral transfer may be visualized as
45  *	Get data from memory to DMAC
46  *	Until no data left
47  *		On burst request from peripheral
48  *			Destination burst from DMAC to peripheral
49  *			Clear burst request
50  *	Raise terminal count interrupt
51  *
52  * For peripherals with a FIFO:
53  * Source      burst size == half the depth of the peripheral FIFO
54  * Destination burst size == the depth of the peripheral FIFO
55  *
56  * (Bursts are irrelevant for mem to mem transfers - there are no burst
57  * signals, the DMA controller will simply facilitate its AHB master.)
58  *
59  * ASSUMES default (little) endianness for DMA transfers
60  *
61  * The PL08x has two flow control settings:
62  *  - DMAC flow control: the transfer size defines the number of transfers
63  *    which occur for the current LLI entry, and the DMAC raises TC at the
64  *    end of every LLI entry.  Observed behaviour shows the DMAC listening
65  *    to both the BREQ and SREQ signals (contrary to documented),
66  *    transferring data if either is active.  The LBREQ and LSREQ signals
67  *    are ignored.
68  *
69  *  - Peripheral flow control: the transfer size is ignored (and should be
70  *    zero).  The data is transferred from the current LLI entry, until
71  *    after the final transfer signalled by LBREQ or LSREQ.  The DMAC
72  *    will then move to the next LLI entry. Unsupported by PL080S.
73  */
74 #include <linux/amba/bus.h>
75 #include <linux/amba/pl08x.h>
76 #include <linux/debugfs.h>
77 #include <linux/delay.h>
78 #include <linux/device.h>
79 #include <linux/dmaengine.h>
80 #include <linux/dmapool.h>
81 #include <linux/dma-mapping.h>
82 #include <linux/export.h>
83 #include <linux/init.h>
84 #include <linux/interrupt.h>
85 #include <linux/module.h>
86 #include <linux/of.h>
87 #include <linux/of_dma.h>
88 #include <linux/pm_runtime.h>
89 #include <linux/seq_file.h>
90 #include <linux/slab.h>
91 #include <linux/amba/pl080.h>
92 
93 #include "dmaengine.h"
94 #include "virt-dma.h"
95 
96 #define DRIVER_NAME	"pl08xdmac"
97 
98 #define PL80X_DMA_BUSWIDTHS \
99 	BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) | \
100 	BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
101 	BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
102 	BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)
103 
104 static struct amba_driver pl08x_amba_driver;
105 struct pl08x_driver_data;
106 
107 /**
108  * struct vendor_data - vendor-specific config parameters for PL08x derivatives
109  * @channels: the number of channels available in this variant
110  * @signals: the number of request signals available from the hardware
111  * @dualmaster: whether this version supports dual AHB masters or not.
112  * @nomadik: whether the channels have Nomadik security extension bits
113  *	that need to be checked for permission before use and some registers are
114  *	missing
115  * @pl080s: whether this version is a PL080S, which has separate register and
116  *	LLI word for transfer size.
117  * @max_transfer_size: the maximum single element transfer size for this
118  *	PL08x variant.
119  */
120 struct vendor_data {
121 	u8 config_offset;
122 	u8 channels;
123 	u8 signals;
124 	bool dualmaster;
125 	bool nomadik;
126 	bool pl080s;
127 	u32 max_transfer_size;
128 };
129 
130 /**
131  * struct pl08x_bus_data - information of source or destination
132  * busses for a transfer
133  * @addr: current address
134  * @maxwidth: the maximum width of a transfer on this bus
135  * @buswidth: the width of this bus in bytes: 1, 2 or 4
136  */
137 struct pl08x_bus_data {
138 	dma_addr_t addr;
139 	u8 maxwidth;
140 	u8 buswidth;
141 };
142 
143 #define IS_BUS_ALIGNED(bus) IS_ALIGNED((bus)->addr, (bus)->buswidth)
144 
145 /**
146  * struct pl08x_phy_chan - holder for the physical channels
147  * @id: physical index to this channel
148  * @lock: a lock to use when altering an instance of this struct
149  * @serving: the virtual channel currently being served by this physical
150  * channel
151  * @locked: channel unavailable for the system, e.g. dedicated to secure
152  * world
153  */
154 struct pl08x_phy_chan {
155 	unsigned int id;
156 	void __iomem *base;
157 	void __iomem *reg_config;
158 	spinlock_t lock;
159 	struct pl08x_dma_chan *serving;
160 	bool locked;
161 };
162 
163 /**
164  * struct pl08x_sg - structure containing data per sg
165  * @src_addr: src address of sg
166  * @dst_addr: dst address of sg
167  * @len: transfer len in bytes
168  * @node: node for txd's dsg_list
169  */
170 struct pl08x_sg {
171 	dma_addr_t src_addr;
172 	dma_addr_t dst_addr;
173 	size_t len;
174 	struct list_head node;
175 };
176 
177 /**
178  * struct pl08x_txd - wrapper for struct dma_async_tx_descriptor
179  * @vd: virtual DMA descriptor
180  * @dsg_list: list of children sg's
181  * @llis_bus: DMA memory address (physical) start for the LLIs
182  * @llis_va: virtual memory address start for the LLIs
183  * @cctl: control reg values for current txd
184  * @ccfg: config reg values for current txd
185  * @done: this marks completed descriptors, which should not have their
186  *   mux released.
187  * @cyclic: indicate cyclic transfers
188  */
189 struct pl08x_txd {
190 	struct virt_dma_desc vd;
191 	struct list_head dsg_list;
192 	dma_addr_t llis_bus;
193 	u32 *llis_va;
194 	/* Default cctl value for LLIs */
195 	u32 cctl;
196 	/*
197 	 * Settings to be put into the physical channel when we
198 	 * trigger this txd.  Other registers are in llis_va[0].
199 	 */
200 	u32 ccfg;
201 	bool done;
202 	bool cyclic;
203 };
204 
205 /**
206  * struct pl08x_dma_chan_state - holds the PL08x specific virtual channel
207  * states
208  * @PL08X_CHAN_IDLE: the channel is idle
209  * @PL08X_CHAN_RUNNING: the channel has allocated a physical transport
210  * channel and is running a transfer on it
211  * @PL08X_CHAN_PAUSED: the channel has allocated a physical transport
212  * channel, but the transfer is currently paused
213  * @PL08X_CHAN_WAITING: the channel is waiting for a physical transport
214  * channel to become available (only pertains to memcpy channels)
215  */
216 enum pl08x_dma_chan_state {
217 	PL08X_CHAN_IDLE,
218 	PL08X_CHAN_RUNNING,
219 	PL08X_CHAN_PAUSED,
220 	PL08X_CHAN_WAITING,
221 };
222 
223 /**
224  * struct pl08x_dma_chan - this structure wraps a DMA ENGINE channel
225  * @vc: wrappped virtual channel
226  * @phychan: the physical channel utilized by this channel, if there is one
227  * @name: name of channel
228  * @cd: channel platform data
229  * @runtime_addr: address for RX/TX according to the runtime config
230  * @at: active transaction on this channel
231  * @lock: a lock for this channel data
232  * @host: a pointer to the host (internal use)
233  * @state: whether the channel is idle, paused, running etc
234  * @slave: whether this channel is a device (slave) or for memcpy
235  * @signal: the physical DMA request signal which this channel is using
236  * @mux_use: count of descriptors using this DMA request signal setting
237  */
238 struct pl08x_dma_chan {
239 	struct virt_dma_chan vc;
240 	struct pl08x_phy_chan *phychan;
241 	const char *name;
242 	struct pl08x_channel_data *cd;
243 	struct dma_slave_config cfg;
244 	struct pl08x_txd *at;
245 	struct pl08x_driver_data *host;
246 	enum pl08x_dma_chan_state state;
247 	bool slave;
248 	int signal;
249 	unsigned mux_use;
250 };
251 
252 /**
253  * struct pl08x_driver_data - the local state holder for the PL08x
254  * @slave: slave engine for this instance
255  * @memcpy: memcpy engine for this instance
256  * @base: virtual memory base (remapped) for the PL08x
257  * @adev: the corresponding AMBA (PrimeCell) bus entry
258  * @vd: vendor data for this PL08x variant
259  * @pd: platform data passed in from the platform/machine
260  * @phy_chans: array of data for the physical channels
261  * @pool: a pool for the LLI descriptors
262  * @lli_buses: bitmask to or in to LLI pointer selecting AHB port for LLI
263  * fetches
264  * @mem_buses: set to indicate memory transfers on AHB2.
265  * @lock: a spinlock for this struct
266  */
267 struct pl08x_driver_data {
268 	struct dma_device slave;
269 	struct dma_device memcpy;
270 	void __iomem *base;
271 	struct amba_device *adev;
272 	const struct vendor_data *vd;
273 	struct pl08x_platform_data *pd;
274 	struct pl08x_phy_chan *phy_chans;
275 	struct dma_pool *pool;
276 	u8 lli_buses;
277 	u8 mem_buses;
278 	u8 lli_words;
279 };
280 
281 /*
282  * PL08X specific defines
283  */
284 
285 /* The order of words in an LLI. */
286 #define PL080_LLI_SRC		0
287 #define PL080_LLI_DST		1
288 #define PL080_LLI_LLI		2
289 #define PL080_LLI_CCTL		3
290 #define PL080S_LLI_CCTL2	4
291 
292 /* Total words in an LLI. */
293 #define PL080_LLI_WORDS		4
294 #define PL080S_LLI_WORDS	8
295 
296 /*
297  * Number of LLIs in each LLI buffer allocated for one transfer
298  * (maximum times we call dma_pool_alloc on this pool without freeing)
299  */
300 #define MAX_NUM_TSFR_LLIS	512
301 #define PL08X_ALIGN		8
302 
303 static inline struct pl08x_dma_chan *to_pl08x_chan(struct dma_chan *chan)
304 {
305 	return container_of(chan, struct pl08x_dma_chan, vc.chan);
306 }
307 
308 static inline struct pl08x_txd *to_pl08x_txd(struct dma_async_tx_descriptor *tx)
309 {
310 	return container_of(tx, struct pl08x_txd, vd.tx);
311 }
312 
313 /*
314  * Mux handling.
315  *
316  * This gives us the DMA request input to the PL08x primecell which the
317  * peripheral described by the channel data will be routed to, possibly
318  * via a board/SoC specific external MUX.  One important point to note
319  * here is that this does not depend on the physical channel.
320  */
321 static int pl08x_request_mux(struct pl08x_dma_chan *plchan)
322 {
323 	const struct pl08x_platform_data *pd = plchan->host->pd;
324 	int ret;
325 
326 	if (plchan->mux_use++ == 0 && pd->get_xfer_signal) {
327 		ret = pd->get_xfer_signal(plchan->cd);
328 		if (ret < 0) {
329 			plchan->mux_use = 0;
330 			return ret;
331 		}
332 
333 		plchan->signal = ret;
334 	}
335 	return 0;
336 }
337 
338 static void pl08x_release_mux(struct pl08x_dma_chan *plchan)
339 {
340 	const struct pl08x_platform_data *pd = plchan->host->pd;
341 
342 	if (plchan->signal >= 0) {
343 		WARN_ON(plchan->mux_use == 0);
344 
345 		if (--plchan->mux_use == 0 && pd->put_xfer_signal) {
346 			pd->put_xfer_signal(plchan->cd, plchan->signal);
347 			plchan->signal = -1;
348 		}
349 	}
350 }
351 
352 /*
353  * Physical channel handling
354  */
355 
356 /* Whether a certain channel is busy or not */
357 static int pl08x_phy_channel_busy(struct pl08x_phy_chan *ch)
358 {
359 	unsigned int val;
360 
361 	val = readl(ch->reg_config);
362 	return val & PL080_CONFIG_ACTIVE;
363 }
364 
365 static void pl08x_write_lli(struct pl08x_driver_data *pl08x,
366 		struct pl08x_phy_chan *phychan, const u32 *lli, u32 ccfg)
367 {
368 	if (pl08x->vd->pl080s)
369 		dev_vdbg(&pl08x->adev->dev,
370 			"WRITE channel %d: csrc=0x%08x, cdst=0x%08x, "
371 			"clli=0x%08x, cctl=0x%08x, cctl2=0x%08x, ccfg=0x%08x\n",
372 			phychan->id, lli[PL080_LLI_SRC], lli[PL080_LLI_DST],
373 			lli[PL080_LLI_LLI], lli[PL080_LLI_CCTL],
374 			lli[PL080S_LLI_CCTL2], ccfg);
375 	else
376 		dev_vdbg(&pl08x->adev->dev,
377 			"WRITE channel %d: csrc=0x%08x, cdst=0x%08x, "
378 			"clli=0x%08x, cctl=0x%08x, ccfg=0x%08x\n",
379 			phychan->id, lli[PL080_LLI_SRC], lli[PL080_LLI_DST],
380 			lli[PL080_LLI_LLI], lli[PL080_LLI_CCTL], ccfg);
381 
382 	writel_relaxed(lli[PL080_LLI_SRC], phychan->base + PL080_CH_SRC_ADDR);
383 	writel_relaxed(lli[PL080_LLI_DST], phychan->base + PL080_CH_DST_ADDR);
384 	writel_relaxed(lli[PL080_LLI_LLI], phychan->base + PL080_CH_LLI);
385 	writel_relaxed(lli[PL080_LLI_CCTL], phychan->base + PL080_CH_CONTROL);
386 
387 	if (pl08x->vd->pl080s)
388 		writel_relaxed(lli[PL080S_LLI_CCTL2],
389 				phychan->base + PL080S_CH_CONTROL2);
390 
391 	writel(ccfg, phychan->reg_config);
392 }
393 
394 /*
395  * Set the initial DMA register values i.e. those for the first LLI
396  * The next LLI pointer and the configuration interrupt bit have
397  * been set when the LLIs were constructed.  Poke them into the hardware
398  * and start the transfer.
399  */
400 static void pl08x_start_next_txd(struct pl08x_dma_chan *plchan)
401 {
402 	struct pl08x_driver_data *pl08x = plchan->host;
403 	struct pl08x_phy_chan *phychan = plchan->phychan;
404 	struct virt_dma_desc *vd = vchan_next_desc(&plchan->vc);
405 	struct pl08x_txd *txd = to_pl08x_txd(&vd->tx);
406 	u32 val;
407 
408 	list_del(&txd->vd.node);
409 
410 	plchan->at = txd;
411 
412 	/* Wait for channel inactive */
413 	while (pl08x_phy_channel_busy(phychan))
414 		cpu_relax();
415 
416 	pl08x_write_lli(pl08x, phychan, &txd->llis_va[0], txd->ccfg);
417 
418 	/* Enable the DMA channel */
419 	/* Do not access config register until channel shows as disabled */
420 	while (readl(pl08x->base + PL080_EN_CHAN) & (1 << phychan->id))
421 		cpu_relax();
422 
423 	/* Do not access config register until channel shows as inactive */
424 	val = readl(phychan->reg_config);
425 	while ((val & PL080_CONFIG_ACTIVE) || (val & PL080_CONFIG_ENABLE))
426 		val = readl(phychan->reg_config);
427 
428 	writel(val | PL080_CONFIG_ENABLE, phychan->reg_config);
429 }
430 
431 /*
432  * Pause the channel by setting the HALT bit.
433  *
434  * For M->P transfers, pause the DMAC first and then stop the peripheral -
435  * the FIFO can only drain if the peripheral is still requesting data.
436  * (note: this can still timeout if the DMAC FIFO never drains of data.)
437  *
438  * For P->M transfers, disable the peripheral first to stop it filling
439  * the DMAC FIFO, and then pause the DMAC.
440  */
441 static void pl08x_pause_phy_chan(struct pl08x_phy_chan *ch)
442 {
443 	u32 val;
444 	int timeout;
445 
446 	/* Set the HALT bit and wait for the FIFO to drain */
447 	val = readl(ch->reg_config);
448 	val |= PL080_CONFIG_HALT;
449 	writel(val, ch->reg_config);
450 
451 	/* Wait for channel inactive */
452 	for (timeout = 1000; timeout; timeout--) {
453 		if (!pl08x_phy_channel_busy(ch))
454 			break;
455 		udelay(1);
456 	}
457 	if (pl08x_phy_channel_busy(ch))
458 		pr_err("pl08x: channel%u timeout waiting for pause\n", ch->id);
459 }
460 
461 static void pl08x_resume_phy_chan(struct pl08x_phy_chan *ch)
462 {
463 	u32 val;
464 
465 	/* Clear the HALT bit */
466 	val = readl(ch->reg_config);
467 	val &= ~PL080_CONFIG_HALT;
468 	writel(val, ch->reg_config);
469 }
470 
471 /*
472  * pl08x_terminate_phy_chan() stops the channel, clears the FIFO and
473  * clears any pending interrupt status.  This should not be used for
474  * an on-going transfer, but as a method of shutting down a channel
475  * (eg, when it's no longer used) or terminating a transfer.
476  */
477 static void pl08x_terminate_phy_chan(struct pl08x_driver_data *pl08x,
478 	struct pl08x_phy_chan *ch)
479 {
480 	u32 val = readl(ch->reg_config);
481 
482 	val &= ~(PL080_CONFIG_ENABLE | PL080_CONFIG_ERR_IRQ_MASK |
483 		 PL080_CONFIG_TC_IRQ_MASK);
484 
485 	writel(val, ch->reg_config);
486 
487 	writel(1 << ch->id, pl08x->base + PL080_ERR_CLEAR);
488 	writel(1 << ch->id, pl08x->base + PL080_TC_CLEAR);
489 }
490 
491 static inline u32 get_bytes_in_cctl(u32 cctl)
492 {
493 	/* The source width defines the number of bytes */
494 	u32 bytes = cctl & PL080_CONTROL_TRANSFER_SIZE_MASK;
495 
496 	cctl &= PL080_CONTROL_SWIDTH_MASK;
497 
498 	switch (cctl >> PL080_CONTROL_SWIDTH_SHIFT) {
499 	case PL080_WIDTH_8BIT:
500 		break;
501 	case PL080_WIDTH_16BIT:
502 		bytes *= 2;
503 		break;
504 	case PL080_WIDTH_32BIT:
505 		bytes *= 4;
506 		break;
507 	}
508 	return bytes;
509 }
510 
511 static inline u32 get_bytes_in_cctl_pl080s(u32 cctl, u32 cctl1)
512 {
513 	/* The source width defines the number of bytes */
514 	u32 bytes = cctl1 & PL080S_CONTROL_TRANSFER_SIZE_MASK;
515 
516 	cctl &= PL080_CONTROL_SWIDTH_MASK;
517 
518 	switch (cctl >> PL080_CONTROL_SWIDTH_SHIFT) {
519 	case PL080_WIDTH_8BIT:
520 		break;
521 	case PL080_WIDTH_16BIT:
522 		bytes *= 2;
523 		break;
524 	case PL080_WIDTH_32BIT:
525 		bytes *= 4;
526 		break;
527 	}
528 	return bytes;
529 }
530 
531 /* The channel should be paused when calling this */
532 static u32 pl08x_getbytes_chan(struct pl08x_dma_chan *plchan)
533 {
534 	struct pl08x_driver_data *pl08x = plchan->host;
535 	const u32 *llis_va, *llis_va_limit;
536 	struct pl08x_phy_chan *ch;
537 	dma_addr_t llis_bus;
538 	struct pl08x_txd *txd;
539 	u32 llis_max_words;
540 	size_t bytes;
541 	u32 clli;
542 
543 	ch = plchan->phychan;
544 	txd = plchan->at;
545 
546 	if (!ch || !txd)
547 		return 0;
548 
549 	/*
550 	 * Follow the LLIs to get the number of remaining
551 	 * bytes in the currently active transaction.
552 	 */
553 	clli = readl(ch->base + PL080_CH_LLI) & ~PL080_LLI_LM_AHB2;
554 
555 	/* First get the remaining bytes in the active transfer */
556 	if (pl08x->vd->pl080s)
557 		bytes = get_bytes_in_cctl_pl080s(
558 				readl(ch->base + PL080_CH_CONTROL),
559 				readl(ch->base + PL080S_CH_CONTROL2));
560 	else
561 		bytes = get_bytes_in_cctl(readl(ch->base + PL080_CH_CONTROL));
562 
563 	if (!clli)
564 		return bytes;
565 
566 	llis_va = txd->llis_va;
567 	llis_bus = txd->llis_bus;
568 
569 	llis_max_words = pl08x->lli_words * MAX_NUM_TSFR_LLIS;
570 	BUG_ON(clli < llis_bus || clli >= llis_bus +
571 						sizeof(u32) * llis_max_words);
572 
573 	/*
574 	 * Locate the next LLI - as this is an array,
575 	 * it's simple maths to find.
576 	 */
577 	llis_va += (clli - llis_bus) / sizeof(u32);
578 
579 	llis_va_limit = llis_va + llis_max_words;
580 
581 	for (; llis_va < llis_va_limit; llis_va += pl08x->lli_words) {
582 		if (pl08x->vd->pl080s)
583 			bytes += get_bytes_in_cctl_pl080s(
584 						llis_va[PL080_LLI_CCTL],
585 						llis_va[PL080S_LLI_CCTL2]);
586 		else
587 			bytes += get_bytes_in_cctl(llis_va[PL080_LLI_CCTL]);
588 
589 		/*
590 		 * A LLI pointer going backward terminates the LLI list
591 		 */
592 		if (llis_va[PL080_LLI_LLI] <= clli)
593 			break;
594 	}
595 
596 	return bytes;
597 }
598 
599 /*
600  * Allocate a physical channel for a virtual channel
601  *
602  * Try to locate a physical channel to be used for this transfer. If all
603  * are taken return NULL and the requester will have to cope by using
604  * some fallback PIO mode or retrying later.
605  */
606 static struct pl08x_phy_chan *
607 pl08x_get_phy_channel(struct pl08x_driver_data *pl08x,
608 		      struct pl08x_dma_chan *virt_chan)
609 {
610 	struct pl08x_phy_chan *ch = NULL;
611 	unsigned long flags;
612 	int i;
613 
614 	for (i = 0; i < pl08x->vd->channels; i++) {
615 		ch = &pl08x->phy_chans[i];
616 
617 		spin_lock_irqsave(&ch->lock, flags);
618 
619 		if (!ch->locked && !ch->serving) {
620 			ch->serving = virt_chan;
621 			spin_unlock_irqrestore(&ch->lock, flags);
622 			break;
623 		}
624 
625 		spin_unlock_irqrestore(&ch->lock, flags);
626 	}
627 
628 	if (i == pl08x->vd->channels) {
629 		/* No physical channel available, cope with it */
630 		return NULL;
631 	}
632 
633 	return ch;
634 }
635 
636 /* Mark the physical channel as free.  Note, this write is atomic. */
637 static inline void pl08x_put_phy_channel(struct pl08x_driver_data *pl08x,
638 					 struct pl08x_phy_chan *ch)
639 {
640 	ch->serving = NULL;
641 }
642 
643 /*
644  * Try to allocate a physical channel.  When successful, assign it to
645  * this virtual channel, and initiate the next descriptor.  The
646  * virtual channel lock must be held at this point.
647  */
648 static void pl08x_phy_alloc_and_start(struct pl08x_dma_chan *plchan)
649 {
650 	struct pl08x_driver_data *pl08x = plchan->host;
651 	struct pl08x_phy_chan *ch;
652 
653 	ch = pl08x_get_phy_channel(pl08x, plchan);
654 	if (!ch) {
655 		dev_dbg(&pl08x->adev->dev, "no physical channel available for xfer on %s\n", plchan->name);
656 		plchan->state = PL08X_CHAN_WAITING;
657 		return;
658 	}
659 
660 	dev_dbg(&pl08x->adev->dev, "allocated physical channel %d for xfer on %s\n",
661 		ch->id, plchan->name);
662 
663 	plchan->phychan = ch;
664 	plchan->state = PL08X_CHAN_RUNNING;
665 	pl08x_start_next_txd(plchan);
666 }
667 
668 static void pl08x_phy_reassign_start(struct pl08x_phy_chan *ch,
669 	struct pl08x_dma_chan *plchan)
670 {
671 	struct pl08x_driver_data *pl08x = plchan->host;
672 
673 	dev_dbg(&pl08x->adev->dev, "reassigned physical channel %d for xfer on %s\n",
674 		ch->id, plchan->name);
675 
676 	/*
677 	 * We do this without taking the lock; we're really only concerned
678 	 * about whether this pointer is NULL or not, and we're guaranteed
679 	 * that this will only be called when it _already_ is non-NULL.
680 	 */
681 	ch->serving = plchan;
682 	plchan->phychan = ch;
683 	plchan->state = PL08X_CHAN_RUNNING;
684 	pl08x_start_next_txd(plchan);
685 }
686 
687 /*
688  * Free a physical DMA channel, potentially reallocating it to another
689  * virtual channel if we have any pending.
690  */
691 static void pl08x_phy_free(struct pl08x_dma_chan *plchan)
692 {
693 	struct pl08x_driver_data *pl08x = plchan->host;
694 	struct pl08x_dma_chan *p, *next;
695 
696  retry:
697 	next = NULL;
698 
699 	/* Find a waiting virtual channel for the next transfer. */
700 	list_for_each_entry(p, &pl08x->memcpy.channels, vc.chan.device_node)
701 		if (p->state == PL08X_CHAN_WAITING) {
702 			next = p;
703 			break;
704 		}
705 
706 	if (!next) {
707 		list_for_each_entry(p, &pl08x->slave.channels, vc.chan.device_node)
708 			if (p->state == PL08X_CHAN_WAITING) {
709 				next = p;
710 				break;
711 			}
712 	}
713 
714 	/* Ensure that the physical channel is stopped */
715 	pl08x_terminate_phy_chan(pl08x, plchan->phychan);
716 
717 	if (next) {
718 		bool success;
719 
720 		/*
721 		 * Eww.  We know this isn't going to deadlock
722 		 * but lockdep probably doesn't.
723 		 */
724 		spin_lock(&next->vc.lock);
725 		/* Re-check the state now that we have the lock */
726 		success = next->state == PL08X_CHAN_WAITING;
727 		if (success)
728 			pl08x_phy_reassign_start(plchan->phychan, next);
729 		spin_unlock(&next->vc.lock);
730 
731 		/* If the state changed, try to find another channel */
732 		if (!success)
733 			goto retry;
734 	} else {
735 		/* No more jobs, so free up the physical channel */
736 		pl08x_put_phy_channel(pl08x, plchan->phychan);
737 	}
738 
739 	plchan->phychan = NULL;
740 	plchan->state = PL08X_CHAN_IDLE;
741 }
742 
743 /*
744  * LLI handling
745  */
746 
747 static inline unsigned int pl08x_get_bytes_for_cctl(unsigned int coded)
748 {
749 	switch (coded) {
750 	case PL080_WIDTH_8BIT:
751 		return 1;
752 	case PL080_WIDTH_16BIT:
753 		return 2;
754 	case PL080_WIDTH_32BIT:
755 		return 4;
756 	default:
757 		break;
758 	}
759 	BUG();
760 	return 0;
761 }
762 
763 static inline u32 pl08x_cctl_bits(u32 cctl, u8 srcwidth, u8 dstwidth,
764 				  size_t tsize)
765 {
766 	u32 retbits = cctl;
767 
768 	/* Remove all src, dst and transfer size bits */
769 	retbits &= ~PL080_CONTROL_DWIDTH_MASK;
770 	retbits &= ~PL080_CONTROL_SWIDTH_MASK;
771 	retbits &= ~PL080_CONTROL_TRANSFER_SIZE_MASK;
772 
773 	/* Then set the bits according to the parameters */
774 	switch (srcwidth) {
775 	case 1:
776 		retbits |= PL080_WIDTH_8BIT << PL080_CONTROL_SWIDTH_SHIFT;
777 		break;
778 	case 2:
779 		retbits |= PL080_WIDTH_16BIT << PL080_CONTROL_SWIDTH_SHIFT;
780 		break;
781 	case 4:
782 		retbits |= PL080_WIDTH_32BIT << PL080_CONTROL_SWIDTH_SHIFT;
783 		break;
784 	default:
785 		BUG();
786 		break;
787 	}
788 
789 	switch (dstwidth) {
790 	case 1:
791 		retbits |= PL080_WIDTH_8BIT << PL080_CONTROL_DWIDTH_SHIFT;
792 		break;
793 	case 2:
794 		retbits |= PL080_WIDTH_16BIT << PL080_CONTROL_DWIDTH_SHIFT;
795 		break;
796 	case 4:
797 		retbits |= PL080_WIDTH_32BIT << PL080_CONTROL_DWIDTH_SHIFT;
798 		break;
799 	default:
800 		BUG();
801 		break;
802 	}
803 
804 	tsize &= PL080_CONTROL_TRANSFER_SIZE_MASK;
805 	retbits |= tsize << PL080_CONTROL_TRANSFER_SIZE_SHIFT;
806 	return retbits;
807 }
808 
809 struct pl08x_lli_build_data {
810 	struct pl08x_txd *txd;
811 	struct pl08x_bus_data srcbus;
812 	struct pl08x_bus_data dstbus;
813 	size_t remainder;
814 	u32 lli_bus;
815 };
816 
817 /*
818  * Autoselect a master bus to use for the transfer. Slave will be the chosen as
819  * victim in case src & dest are not similarly aligned. i.e. If after aligning
820  * masters address with width requirements of transfer (by sending few byte by
821  * byte data), slave is still not aligned, then its width will be reduced to
822  * BYTE.
823  * - prefers the destination bus if both available
824  * - prefers bus with fixed address (i.e. peripheral)
825  */
826 static void pl08x_choose_master_bus(struct pl08x_lli_build_data *bd,
827 	struct pl08x_bus_data **mbus, struct pl08x_bus_data **sbus, u32 cctl)
828 {
829 	if (!(cctl & PL080_CONTROL_DST_INCR)) {
830 		*mbus = &bd->dstbus;
831 		*sbus = &bd->srcbus;
832 	} else if (!(cctl & PL080_CONTROL_SRC_INCR)) {
833 		*mbus = &bd->srcbus;
834 		*sbus = &bd->dstbus;
835 	} else {
836 		if (bd->dstbus.buswidth >= bd->srcbus.buswidth) {
837 			*mbus = &bd->dstbus;
838 			*sbus = &bd->srcbus;
839 		} else {
840 			*mbus = &bd->srcbus;
841 			*sbus = &bd->dstbus;
842 		}
843 	}
844 }
845 
846 /*
847  * Fills in one LLI for a certain transfer descriptor and advance the counter
848  */
849 static void pl08x_fill_lli_for_desc(struct pl08x_driver_data *pl08x,
850 				    struct pl08x_lli_build_data *bd,
851 				    int num_llis, int len, u32 cctl, u32 cctl2)
852 {
853 	u32 offset = num_llis * pl08x->lli_words;
854 	u32 *llis_va = bd->txd->llis_va + offset;
855 	dma_addr_t llis_bus = bd->txd->llis_bus;
856 
857 	BUG_ON(num_llis >= MAX_NUM_TSFR_LLIS);
858 
859 	/* Advance the offset to next LLI. */
860 	offset += pl08x->lli_words;
861 
862 	llis_va[PL080_LLI_SRC] = bd->srcbus.addr;
863 	llis_va[PL080_LLI_DST] = bd->dstbus.addr;
864 	llis_va[PL080_LLI_LLI] = (llis_bus + sizeof(u32) * offset);
865 	llis_va[PL080_LLI_LLI] |= bd->lli_bus;
866 	llis_va[PL080_LLI_CCTL] = cctl;
867 	if (pl08x->vd->pl080s)
868 		llis_va[PL080S_LLI_CCTL2] = cctl2;
869 
870 	if (cctl & PL080_CONTROL_SRC_INCR)
871 		bd->srcbus.addr += len;
872 	if (cctl & PL080_CONTROL_DST_INCR)
873 		bd->dstbus.addr += len;
874 
875 	BUG_ON(bd->remainder < len);
876 
877 	bd->remainder -= len;
878 }
879 
880 static inline void prep_byte_width_lli(struct pl08x_driver_data *pl08x,
881 			struct pl08x_lli_build_data *bd, u32 *cctl, u32 len,
882 			int num_llis, size_t *total_bytes)
883 {
884 	*cctl = pl08x_cctl_bits(*cctl, 1, 1, len);
885 	pl08x_fill_lli_for_desc(pl08x, bd, num_llis, len, *cctl, len);
886 	(*total_bytes) += len;
887 }
888 
889 #ifdef VERBOSE_DEBUG
890 static void pl08x_dump_lli(struct pl08x_driver_data *pl08x,
891 			   const u32 *llis_va, int num_llis)
892 {
893 	int i;
894 
895 	if (pl08x->vd->pl080s) {
896 		dev_vdbg(&pl08x->adev->dev,
897 			"%-3s %-9s  %-10s %-10s %-10s %-10s %s\n",
898 			"lli", "", "csrc", "cdst", "clli", "cctl", "cctl2");
899 		for (i = 0; i < num_llis; i++) {
900 			dev_vdbg(&pl08x->adev->dev,
901 				"%3d @%p: 0x%08x 0x%08x 0x%08x 0x%08x 0x%08x\n",
902 				i, llis_va, llis_va[PL080_LLI_SRC],
903 				llis_va[PL080_LLI_DST], llis_va[PL080_LLI_LLI],
904 				llis_va[PL080_LLI_CCTL],
905 				llis_va[PL080S_LLI_CCTL2]);
906 			llis_va += pl08x->lli_words;
907 		}
908 	} else {
909 		dev_vdbg(&pl08x->adev->dev,
910 			"%-3s %-9s  %-10s %-10s %-10s %s\n",
911 			"lli", "", "csrc", "cdst", "clli", "cctl");
912 		for (i = 0; i < num_llis; i++) {
913 			dev_vdbg(&pl08x->adev->dev,
914 				"%3d @%p: 0x%08x 0x%08x 0x%08x 0x%08x\n",
915 				i, llis_va, llis_va[PL080_LLI_SRC],
916 				llis_va[PL080_LLI_DST], llis_va[PL080_LLI_LLI],
917 				llis_va[PL080_LLI_CCTL]);
918 			llis_va += pl08x->lli_words;
919 		}
920 	}
921 }
922 #else
923 static inline void pl08x_dump_lli(struct pl08x_driver_data *pl08x,
924 				  const u32 *llis_va, int num_llis) {}
925 #endif
926 
927 /*
928  * This fills in the table of LLIs for the transfer descriptor
929  * Note that we assume we never have to change the burst sizes
930  * Return 0 for error
931  */
932 static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
933 			      struct pl08x_txd *txd)
934 {
935 	struct pl08x_bus_data *mbus, *sbus;
936 	struct pl08x_lli_build_data bd;
937 	int num_llis = 0;
938 	u32 cctl, early_bytes = 0;
939 	size_t max_bytes_per_lli, total_bytes;
940 	u32 *llis_va, *last_lli;
941 	struct pl08x_sg *dsg;
942 
943 	txd->llis_va = dma_pool_alloc(pl08x->pool, GFP_NOWAIT, &txd->llis_bus);
944 	if (!txd->llis_va) {
945 		dev_err(&pl08x->adev->dev, "%s no memory for llis\n", __func__);
946 		return 0;
947 	}
948 
949 	bd.txd = txd;
950 	bd.lli_bus = (pl08x->lli_buses & PL08X_AHB2) ? PL080_LLI_LM_AHB2 : 0;
951 	cctl = txd->cctl;
952 
953 	/* Find maximum width of the source bus */
954 	bd.srcbus.maxwidth =
955 		pl08x_get_bytes_for_cctl((cctl & PL080_CONTROL_SWIDTH_MASK) >>
956 				       PL080_CONTROL_SWIDTH_SHIFT);
957 
958 	/* Find maximum width of the destination bus */
959 	bd.dstbus.maxwidth =
960 		pl08x_get_bytes_for_cctl((cctl & PL080_CONTROL_DWIDTH_MASK) >>
961 				       PL080_CONTROL_DWIDTH_SHIFT);
962 
963 	list_for_each_entry(dsg, &txd->dsg_list, node) {
964 		total_bytes = 0;
965 		cctl = txd->cctl;
966 
967 		bd.srcbus.addr = dsg->src_addr;
968 		bd.dstbus.addr = dsg->dst_addr;
969 		bd.remainder = dsg->len;
970 		bd.srcbus.buswidth = bd.srcbus.maxwidth;
971 		bd.dstbus.buswidth = bd.dstbus.maxwidth;
972 
973 		pl08x_choose_master_bus(&bd, &mbus, &sbus, cctl);
974 
975 		dev_vdbg(&pl08x->adev->dev,
976 			"src=0x%08llx%s/%u dst=0x%08llx%s/%u len=%zu\n",
977 			(u64)bd.srcbus.addr,
978 			cctl & PL080_CONTROL_SRC_INCR ? "+" : "",
979 			bd.srcbus.buswidth,
980 			(u64)bd.dstbus.addr,
981 			cctl & PL080_CONTROL_DST_INCR ? "+" : "",
982 			bd.dstbus.buswidth,
983 			bd.remainder);
984 		dev_vdbg(&pl08x->adev->dev, "mbus=%s sbus=%s\n",
985 			mbus == &bd.srcbus ? "src" : "dst",
986 			sbus == &bd.srcbus ? "src" : "dst");
987 
988 		/*
989 		 * Zero length is only allowed if all these requirements are
990 		 * met:
991 		 * - flow controller is peripheral.
992 		 * - src.addr is aligned to src.width
993 		 * - dst.addr is aligned to dst.width
994 		 *
995 		 * sg_len == 1 should be true, as there can be two cases here:
996 		 *
997 		 * - Memory addresses are contiguous and are not scattered.
998 		 *   Here, Only one sg will be passed by user driver, with
999 		 *   memory address and zero length. We pass this to controller
1000 		 *   and after the transfer it will receive the last burst
1001 		 *   request from peripheral and so transfer finishes.
1002 		 *
1003 		 * - Memory addresses are scattered and are not contiguous.
1004 		 *   Here, Obviously as DMA controller doesn't know when a lli's
1005 		 *   transfer gets over, it can't load next lli. So in this
1006 		 *   case, there has to be an assumption that only one lli is
1007 		 *   supported. Thus, we can't have scattered addresses.
1008 		 */
1009 		if (!bd.remainder) {
1010 			u32 fc = (txd->ccfg & PL080_CONFIG_FLOW_CONTROL_MASK) >>
1011 				PL080_CONFIG_FLOW_CONTROL_SHIFT;
1012 			if (!((fc >= PL080_FLOW_SRC2DST_DST) &&
1013 					(fc <= PL080_FLOW_SRC2DST_SRC))) {
1014 				dev_err(&pl08x->adev->dev, "%s sg len can't be zero",
1015 					__func__);
1016 				return 0;
1017 			}
1018 
1019 			if (!IS_BUS_ALIGNED(&bd.srcbus) ||
1020 				!IS_BUS_ALIGNED(&bd.dstbus)) {
1021 				dev_err(&pl08x->adev->dev,
1022 					"%s src & dst address must be aligned to src"
1023 					" & dst width if peripheral is flow controller",
1024 					__func__);
1025 				return 0;
1026 			}
1027 
1028 			cctl = pl08x_cctl_bits(cctl, bd.srcbus.buswidth,
1029 					bd.dstbus.buswidth, 0);
1030 			pl08x_fill_lli_for_desc(pl08x, &bd, num_llis++,
1031 					0, cctl, 0);
1032 			break;
1033 		}
1034 
1035 		/*
1036 		 * Send byte by byte for following cases
1037 		 * - Less than a bus width available
1038 		 * - until master bus is aligned
1039 		 */
1040 		if (bd.remainder < mbus->buswidth)
1041 			early_bytes = bd.remainder;
1042 		else if (!IS_BUS_ALIGNED(mbus)) {
1043 			early_bytes = mbus->buswidth -
1044 				(mbus->addr & (mbus->buswidth - 1));
1045 			if ((bd.remainder - early_bytes) < mbus->buswidth)
1046 				early_bytes = bd.remainder;
1047 		}
1048 
1049 		if (early_bytes) {
1050 			dev_vdbg(&pl08x->adev->dev,
1051 				"%s byte width LLIs (remain 0x%08zx)\n",
1052 				__func__, bd.remainder);
1053 			prep_byte_width_lli(pl08x, &bd, &cctl, early_bytes,
1054 				num_llis++, &total_bytes);
1055 		}
1056 
1057 		if (bd.remainder) {
1058 			/*
1059 			 * Master now aligned
1060 			 * - if slave is not then we must set its width down
1061 			 */
1062 			if (!IS_BUS_ALIGNED(sbus)) {
1063 				dev_dbg(&pl08x->adev->dev,
1064 					"%s set down bus width to one byte\n",
1065 					__func__);
1066 
1067 				sbus->buswidth = 1;
1068 			}
1069 
1070 			/*
1071 			 * Bytes transferred = tsize * src width, not
1072 			 * MIN(buswidths)
1073 			 */
1074 			max_bytes_per_lli = bd.srcbus.buswidth *
1075 						pl08x->vd->max_transfer_size;
1076 			dev_vdbg(&pl08x->adev->dev,
1077 				"%s max bytes per lli = %zu\n",
1078 				__func__, max_bytes_per_lli);
1079 
1080 			/*
1081 			 * Make largest possible LLIs until less than one bus
1082 			 * width left
1083 			 */
1084 			while (bd.remainder > (mbus->buswidth - 1)) {
1085 				size_t lli_len, tsize, width;
1086 
1087 				/*
1088 				 * If enough left try to send max possible,
1089 				 * otherwise try to send the remainder
1090 				 */
1091 				lli_len = min(bd.remainder, max_bytes_per_lli);
1092 
1093 				/*
1094 				 * Check against maximum bus alignment:
1095 				 * Calculate actual transfer size in relation to
1096 				 * bus width an get a maximum remainder of the
1097 				 * highest bus width - 1
1098 				 */
1099 				width = max(mbus->buswidth, sbus->buswidth);
1100 				lli_len = (lli_len / width) * width;
1101 				tsize = lli_len / bd.srcbus.buswidth;
1102 
1103 				dev_vdbg(&pl08x->adev->dev,
1104 					"%s fill lli with single lli chunk of "
1105 					"size 0x%08zx (remainder 0x%08zx)\n",
1106 					__func__, lli_len, bd.remainder);
1107 
1108 				cctl = pl08x_cctl_bits(cctl, bd.srcbus.buswidth,
1109 					bd.dstbus.buswidth, tsize);
1110 				pl08x_fill_lli_for_desc(pl08x, &bd, num_llis++,
1111 						lli_len, cctl, tsize);
1112 				total_bytes += lli_len;
1113 			}
1114 
1115 			/*
1116 			 * Send any odd bytes
1117 			 */
1118 			if (bd.remainder) {
1119 				dev_vdbg(&pl08x->adev->dev,
1120 					"%s align with boundary, send odd bytes (remain %zu)\n",
1121 					__func__, bd.remainder);
1122 				prep_byte_width_lli(pl08x, &bd, &cctl,
1123 					bd.remainder, num_llis++, &total_bytes);
1124 			}
1125 		}
1126 
1127 		if (total_bytes != dsg->len) {
1128 			dev_err(&pl08x->adev->dev,
1129 				"%s size of encoded lli:s don't match total txd, transferred 0x%08zx from size 0x%08zx\n",
1130 				__func__, total_bytes, dsg->len);
1131 			return 0;
1132 		}
1133 
1134 		if (num_llis >= MAX_NUM_TSFR_LLIS) {
1135 			dev_err(&pl08x->adev->dev,
1136 				"%s need to increase MAX_NUM_TSFR_LLIS from 0x%08x\n",
1137 				__func__, MAX_NUM_TSFR_LLIS);
1138 			return 0;
1139 		}
1140 	}
1141 
1142 	llis_va = txd->llis_va;
1143 	last_lli = llis_va + (num_llis - 1) * pl08x->lli_words;
1144 
1145 	if (txd->cyclic) {
1146 		/* Link back to the first LLI. */
1147 		last_lli[PL080_LLI_LLI] = txd->llis_bus | bd.lli_bus;
1148 	} else {
1149 		/* The final LLI terminates the LLI. */
1150 		last_lli[PL080_LLI_LLI] = 0;
1151 		/* The final LLI element shall also fire an interrupt. */
1152 		last_lli[PL080_LLI_CCTL] |= PL080_CONTROL_TC_IRQ_EN;
1153 	}
1154 
1155 	pl08x_dump_lli(pl08x, llis_va, num_llis);
1156 
1157 	return num_llis;
1158 }
1159 
1160 static void pl08x_free_txd(struct pl08x_driver_data *pl08x,
1161 			   struct pl08x_txd *txd)
1162 {
1163 	struct pl08x_sg *dsg, *_dsg;
1164 
1165 	if (txd->llis_va)
1166 		dma_pool_free(pl08x->pool, txd->llis_va, txd->llis_bus);
1167 
1168 	list_for_each_entry_safe(dsg, _dsg, &txd->dsg_list, node) {
1169 		list_del(&dsg->node);
1170 		kfree(dsg);
1171 	}
1172 
1173 	kfree(txd);
1174 }
1175 
1176 static void pl08x_desc_free(struct virt_dma_desc *vd)
1177 {
1178 	struct pl08x_txd *txd = to_pl08x_txd(&vd->tx);
1179 	struct pl08x_dma_chan *plchan = to_pl08x_chan(vd->tx.chan);
1180 
1181 	dma_descriptor_unmap(&vd->tx);
1182 	if (!txd->done)
1183 		pl08x_release_mux(plchan);
1184 
1185 	pl08x_free_txd(plchan->host, txd);
1186 }
1187 
1188 static void pl08x_free_txd_list(struct pl08x_driver_data *pl08x,
1189 				struct pl08x_dma_chan *plchan)
1190 {
1191 	LIST_HEAD(head);
1192 
1193 	vchan_get_all_descriptors(&plchan->vc, &head);
1194 	vchan_dma_desc_free_list(&plchan->vc, &head);
1195 }
1196 
1197 /*
1198  * The DMA ENGINE API
1199  */
1200 static void pl08x_free_chan_resources(struct dma_chan *chan)
1201 {
1202 	/* Ensure all queued descriptors are freed */
1203 	vchan_free_chan_resources(to_virt_chan(chan));
1204 }
1205 
1206 static struct dma_async_tx_descriptor *pl08x_prep_dma_interrupt(
1207 		struct dma_chan *chan, unsigned long flags)
1208 {
1209 	struct dma_async_tx_descriptor *retval = NULL;
1210 
1211 	return retval;
1212 }
1213 
1214 /*
1215  * Code accessing dma_async_is_complete() in a tight loop may give problems.
1216  * If slaves are relying on interrupts to signal completion this function
1217  * must not be called with interrupts disabled.
1218  */
1219 static enum dma_status pl08x_dma_tx_status(struct dma_chan *chan,
1220 		dma_cookie_t cookie, struct dma_tx_state *txstate)
1221 {
1222 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1223 	struct virt_dma_desc *vd;
1224 	unsigned long flags;
1225 	enum dma_status ret;
1226 	size_t bytes = 0;
1227 
1228 	ret = dma_cookie_status(chan, cookie, txstate);
1229 	if (ret == DMA_COMPLETE)
1230 		return ret;
1231 
1232 	/*
1233 	 * There's no point calculating the residue if there's
1234 	 * no txstate to store the value.
1235 	 */
1236 	if (!txstate) {
1237 		if (plchan->state == PL08X_CHAN_PAUSED)
1238 			ret = DMA_PAUSED;
1239 		return ret;
1240 	}
1241 
1242 	spin_lock_irqsave(&plchan->vc.lock, flags);
1243 	ret = dma_cookie_status(chan, cookie, txstate);
1244 	if (ret != DMA_COMPLETE) {
1245 		vd = vchan_find_desc(&plchan->vc, cookie);
1246 		if (vd) {
1247 			/* On the issued list, so hasn't been processed yet */
1248 			struct pl08x_txd *txd = to_pl08x_txd(&vd->tx);
1249 			struct pl08x_sg *dsg;
1250 
1251 			list_for_each_entry(dsg, &txd->dsg_list, node)
1252 				bytes += dsg->len;
1253 		} else {
1254 			bytes = pl08x_getbytes_chan(plchan);
1255 		}
1256 	}
1257 	spin_unlock_irqrestore(&plchan->vc.lock, flags);
1258 
1259 	/*
1260 	 * This cookie not complete yet
1261 	 * Get number of bytes left in the active transactions and queue
1262 	 */
1263 	dma_set_residue(txstate, bytes);
1264 
1265 	if (plchan->state == PL08X_CHAN_PAUSED && ret == DMA_IN_PROGRESS)
1266 		ret = DMA_PAUSED;
1267 
1268 	/* Whether waiting or running, we're in progress */
1269 	return ret;
1270 }
1271 
1272 /* PrimeCell DMA extension */
1273 struct burst_table {
1274 	u32 burstwords;
1275 	u32 reg;
1276 };
1277 
1278 static const struct burst_table burst_sizes[] = {
1279 	{
1280 		.burstwords = 256,
1281 		.reg = PL080_BSIZE_256,
1282 	},
1283 	{
1284 		.burstwords = 128,
1285 		.reg = PL080_BSIZE_128,
1286 	},
1287 	{
1288 		.burstwords = 64,
1289 		.reg = PL080_BSIZE_64,
1290 	},
1291 	{
1292 		.burstwords = 32,
1293 		.reg = PL080_BSIZE_32,
1294 	},
1295 	{
1296 		.burstwords = 16,
1297 		.reg = PL080_BSIZE_16,
1298 	},
1299 	{
1300 		.burstwords = 8,
1301 		.reg = PL080_BSIZE_8,
1302 	},
1303 	{
1304 		.burstwords = 4,
1305 		.reg = PL080_BSIZE_4,
1306 	},
1307 	{
1308 		.burstwords = 0,
1309 		.reg = PL080_BSIZE_1,
1310 	},
1311 };
1312 
1313 /*
1314  * Given the source and destination available bus masks, select which
1315  * will be routed to each port.  We try to have source and destination
1316  * on separate ports, but always respect the allowable settings.
1317  */
1318 static u32 pl08x_select_bus(u8 src, u8 dst)
1319 {
1320 	u32 cctl = 0;
1321 
1322 	if (!(dst & PL08X_AHB1) || ((dst & PL08X_AHB2) && (src & PL08X_AHB1)))
1323 		cctl |= PL080_CONTROL_DST_AHB2;
1324 	if (!(src & PL08X_AHB1) || ((src & PL08X_AHB2) && !(dst & PL08X_AHB2)))
1325 		cctl |= PL080_CONTROL_SRC_AHB2;
1326 
1327 	return cctl;
1328 }
1329 
1330 static u32 pl08x_cctl(u32 cctl)
1331 {
1332 	cctl &= ~(PL080_CONTROL_SRC_AHB2 | PL080_CONTROL_DST_AHB2 |
1333 		  PL080_CONTROL_SRC_INCR | PL080_CONTROL_DST_INCR |
1334 		  PL080_CONTROL_PROT_MASK);
1335 
1336 	/* Access the cell in privileged mode, non-bufferable, non-cacheable */
1337 	return cctl | PL080_CONTROL_PROT_SYS;
1338 }
1339 
1340 static u32 pl08x_width(enum dma_slave_buswidth width)
1341 {
1342 	switch (width) {
1343 	case DMA_SLAVE_BUSWIDTH_1_BYTE:
1344 		return PL080_WIDTH_8BIT;
1345 	case DMA_SLAVE_BUSWIDTH_2_BYTES:
1346 		return PL080_WIDTH_16BIT;
1347 	case DMA_SLAVE_BUSWIDTH_4_BYTES:
1348 		return PL080_WIDTH_32BIT;
1349 	default:
1350 		return ~0;
1351 	}
1352 }
1353 
1354 static u32 pl08x_burst(u32 maxburst)
1355 {
1356 	int i;
1357 
1358 	for (i = 0; i < ARRAY_SIZE(burst_sizes); i++)
1359 		if (burst_sizes[i].burstwords <= maxburst)
1360 			break;
1361 
1362 	return burst_sizes[i].reg;
1363 }
1364 
1365 static u32 pl08x_get_cctl(struct pl08x_dma_chan *plchan,
1366 	enum dma_slave_buswidth addr_width, u32 maxburst)
1367 {
1368 	u32 width, burst, cctl = 0;
1369 
1370 	width = pl08x_width(addr_width);
1371 	if (width == ~0)
1372 		return ~0;
1373 
1374 	cctl |= width << PL080_CONTROL_SWIDTH_SHIFT;
1375 	cctl |= width << PL080_CONTROL_DWIDTH_SHIFT;
1376 
1377 	/*
1378 	 * If this channel will only request single transfers, set this
1379 	 * down to ONE element.  Also select one element if no maxburst
1380 	 * is specified.
1381 	 */
1382 	if (plchan->cd->single)
1383 		maxburst = 1;
1384 
1385 	burst = pl08x_burst(maxburst);
1386 	cctl |= burst << PL080_CONTROL_SB_SIZE_SHIFT;
1387 	cctl |= burst << PL080_CONTROL_DB_SIZE_SHIFT;
1388 
1389 	return pl08x_cctl(cctl);
1390 }
1391 
1392 /*
1393  * Slave transactions callback to the slave device to allow
1394  * synchronization of slave DMA signals with the DMAC enable
1395  */
1396 static void pl08x_issue_pending(struct dma_chan *chan)
1397 {
1398 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1399 	unsigned long flags;
1400 
1401 	spin_lock_irqsave(&plchan->vc.lock, flags);
1402 	if (vchan_issue_pending(&plchan->vc)) {
1403 		if (!plchan->phychan && plchan->state != PL08X_CHAN_WAITING)
1404 			pl08x_phy_alloc_and_start(plchan);
1405 	}
1406 	spin_unlock_irqrestore(&plchan->vc.lock, flags);
1407 }
1408 
1409 static struct pl08x_txd *pl08x_get_txd(struct pl08x_dma_chan *plchan)
1410 {
1411 	struct pl08x_txd *txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
1412 
1413 	if (txd) {
1414 		INIT_LIST_HEAD(&txd->dsg_list);
1415 
1416 		/* Always enable error and terminal interrupts */
1417 		txd->ccfg = PL080_CONFIG_ERR_IRQ_MASK |
1418 			    PL080_CONFIG_TC_IRQ_MASK;
1419 	}
1420 	return txd;
1421 }
1422 
1423 /*
1424  * Initialize a descriptor to be used by memcpy submit
1425  */
1426 static struct dma_async_tx_descriptor *pl08x_prep_dma_memcpy(
1427 		struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
1428 		size_t len, unsigned long flags)
1429 {
1430 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1431 	struct pl08x_driver_data *pl08x = plchan->host;
1432 	struct pl08x_txd *txd;
1433 	struct pl08x_sg *dsg;
1434 	int ret;
1435 
1436 	txd = pl08x_get_txd(plchan);
1437 	if (!txd) {
1438 		dev_err(&pl08x->adev->dev,
1439 			"%s no memory for descriptor\n", __func__);
1440 		return NULL;
1441 	}
1442 
1443 	dsg = kzalloc(sizeof(struct pl08x_sg), GFP_NOWAIT);
1444 	if (!dsg) {
1445 		pl08x_free_txd(pl08x, txd);
1446 		return NULL;
1447 	}
1448 	list_add_tail(&dsg->node, &txd->dsg_list);
1449 
1450 	dsg->src_addr = src;
1451 	dsg->dst_addr = dest;
1452 	dsg->len = len;
1453 
1454 	/* Set platform data for m2m */
1455 	txd->ccfg |= PL080_FLOW_MEM2MEM << PL080_CONFIG_FLOW_CONTROL_SHIFT;
1456 	txd->cctl = pl08x->pd->memcpy_channel.cctl_memcpy &
1457 			~(PL080_CONTROL_DST_AHB2 | PL080_CONTROL_SRC_AHB2);
1458 
1459 	/* Both to be incremented or the code will break */
1460 	txd->cctl |= PL080_CONTROL_SRC_INCR | PL080_CONTROL_DST_INCR;
1461 
1462 	if (pl08x->vd->dualmaster)
1463 		txd->cctl |= pl08x_select_bus(pl08x->mem_buses,
1464 					      pl08x->mem_buses);
1465 
1466 	ret = pl08x_fill_llis_for_desc(plchan->host, txd);
1467 	if (!ret) {
1468 		pl08x_free_txd(pl08x, txd);
1469 		return NULL;
1470 	}
1471 
1472 	return vchan_tx_prep(&plchan->vc, &txd->vd, flags);
1473 }
1474 
1475 static struct pl08x_txd *pl08x_init_txd(
1476 		struct dma_chan *chan,
1477 		enum dma_transfer_direction direction,
1478 		dma_addr_t *slave_addr)
1479 {
1480 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1481 	struct pl08x_driver_data *pl08x = plchan->host;
1482 	struct pl08x_txd *txd;
1483 	enum dma_slave_buswidth addr_width;
1484 	int ret, tmp;
1485 	u8 src_buses, dst_buses;
1486 	u32 maxburst, cctl;
1487 
1488 	txd = pl08x_get_txd(plchan);
1489 	if (!txd) {
1490 		dev_err(&pl08x->adev->dev, "%s no txd\n", __func__);
1491 		return NULL;
1492 	}
1493 
1494 	/*
1495 	 * Set up addresses, the PrimeCell configured address
1496 	 * will take precedence since this may configure the
1497 	 * channel target address dynamically at runtime.
1498 	 */
1499 	if (direction == DMA_MEM_TO_DEV) {
1500 		cctl = PL080_CONTROL_SRC_INCR;
1501 		*slave_addr = plchan->cfg.dst_addr;
1502 		addr_width = plchan->cfg.dst_addr_width;
1503 		maxburst = plchan->cfg.dst_maxburst;
1504 		src_buses = pl08x->mem_buses;
1505 		dst_buses = plchan->cd->periph_buses;
1506 	} else if (direction == DMA_DEV_TO_MEM) {
1507 		cctl = PL080_CONTROL_DST_INCR;
1508 		*slave_addr = plchan->cfg.src_addr;
1509 		addr_width = plchan->cfg.src_addr_width;
1510 		maxburst = plchan->cfg.src_maxburst;
1511 		src_buses = plchan->cd->periph_buses;
1512 		dst_buses = pl08x->mem_buses;
1513 	} else {
1514 		pl08x_free_txd(pl08x, txd);
1515 		dev_err(&pl08x->adev->dev,
1516 			"%s direction unsupported\n", __func__);
1517 		return NULL;
1518 	}
1519 
1520 	cctl |= pl08x_get_cctl(plchan, addr_width, maxburst);
1521 	if (cctl == ~0) {
1522 		pl08x_free_txd(pl08x, txd);
1523 		dev_err(&pl08x->adev->dev,
1524 			"DMA slave configuration botched?\n");
1525 		return NULL;
1526 	}
1527 
1528 	txd->cctl = cctl | pl08x_select_bus(src_buses, dst_buses);
1529 
1530 	if (plchan->cfg.device_fc)
1531 		tmp = (direction == DMA_MEM_TO_DEV) ? PL080_FLOW_MEM2PER_PER :
1532 			PL080_FLOW_PER2MEM_PER;
1533 	else
1534 		tmp = (direction == DMA_MEM_TO_DEV) ? PL080_FLOW_MEM2PER :
1535 			PL080_FLOW_PER2MEM;
1536 
1537 	txd->ccfg |= tmp << PL080_CONFIG_FLOW_CONTROL_SHIFT;
1538 
1539 	ret = pl08x_request_mux(plchan);
1540 	if (ret < 0) {
1541 		pl08x_free_txd(pl08x, txd);
1542 		dev_dbg(&pl08x->adev->dev,
1543 			"unable to mux for transfer on %s due to platform restrictions\n",
1544 			plchan->name);
1545 		return NULL;
1546 	}
1547 
1548 	dev_dbg(&pl08x->adev->dev, "allocated DMA request signal %d for xfer on %s\n",
1549 		 plchan->signal, plchan->name);
1550 
1551 	/* Assign the flow control signal to this channel */
1552 	if (direction == DMA_MEM_TO_DEV)
1553 		txd->ccfg |= plchan->signal << PL080_CONFIG_DST_SEL_SHIFT;
1554 	else
1555 		txd->ccfg |= plchan->signal << PL080_CONFIG_SRC_SEL_SHIFT;
1556 
1557 	return txd;
1558 }
1559 
1560 static int pl08x_tx_add_sg(struct pl08x_txd *txd,
1561 			   enum dma_transfer_direction direction,
1562 			   dma_addr_t slave_addr,
1563 			   dma_addr_t buf_addr,
1564 			   unsigned int len)
1565 {
1566 	struct pl08x_sg *dsg;
1567 
1568 	dsg = kzalloc(sizeof(struct pl08x_sg), GFP_NOWAIT);
1569 	if (!dsg)
1570 		return -ENOMEM;
1571 
1572 	list_add_tail(&dsg->node, &txd->dsg_list);
1573 
1574 	dsg->len = len;
1575 	if (direction == DMA_MEM_TO_DEV) {
1576 		dsg->src_addr = buf_addr;
1577 		dsg->dst_addr = slave_addr;
1578 	} else {
1579 		dsg->src_addr = slave_addr;
1580 		dsg->dst_addr = buf_addr;
1581 	}
1582 
1583 	return 0;
1584 }
1585 
1586 static struct dma_async_tx_descriptor *pl08x_prep_slave_sg(
1587 		struct dma_chan *chan, struct scatterlist *sgl,
1588 		unsigned int sg_len, enum dma_transfer_direction direction,
1589 		unsigned long flags, void *context)
1590 {
1591 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1592 	struct pl08x_driver_data *pl08x = plchan->host;
1593 	struct pl08x_txd *txd;
1594 	struct scatterlist *sg;
1595 	int ret, tmp;
1596 	dma_addr_t slave_addr;
1597 
1598 	dev_dbg(&pl08x->adev->dev, "%s prepare transaction of %d bytes from %s\n",
1599 			__func__, sg_dma_len(sgl), plchan->name);
1600 
1601 	txd = pl08x_init_txd(chan, direction, &slave_addr);
1602 	if (!txd)
1603 		return NULL;
1604 
1605 	for_each_sg(sgl, sg, sg_len, tmp) {
1606 		ret = pl08x_tx_add_sg(txd, direction, slave_addr,
1607 				      sg_dma_address(sg),
1608 				      sg_dma_len(sg));
1609 		if (ret) {
1610 			pl08x_release_mux(plchan);
1611 			pl08x_free_txd(pl08x, txd);
1612 			dev_err(&pl08x->adev->dev, "%s no mem for pl080 sg\n",
1613 					__func__);
1614 			return NULL;
1615 		}
1616 	}
1617 
1618 	ret = pl08x_fill_llis_for_desc(plchan->host, txd);
1619 	if (!ret) {
1620 		pl08x_release_mux(plchan);
1621 		pl08x_free_txd(pl08x, txd);
1622 		return NULL;
1623 	}
1624 
1625 	return vchan_tx_prep(&plchan->vc, &txd->vd, flags);
1626 }
1627 
1628 static struct dma_async_tx_descriptor *pl08x_prep_dma_cyclic(
1629 		struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
1630 		size_t period_len, enum dma_transfer_direction direction,
1631 		unsigned long flags)
1632 {
1633 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1634 	struct pl08x_driver_data *pl08x = plchan->host;
1635 	struct pl08x_txd *txd;
1636 	int ret, tmp;
1637 	dma_addr_t slave_addr;
1638 
1639 	dev_dbg(&pl08x->adev->dev,
1640 		"%s prepare cyclic transaction of %zd/%zd bytes %s %s\n",
1641 		__func__, period_len, buf_len,
1642 		direction == DMA_MEM_TO_DEV ? "to" : "from",
1643 		plchan->name);
1644 
1645 	txd = pl08x_init_txd(chan, direction, &slave_addr);
1646 	if (!txd)
1647 		return NULL;
1648 
1649 	txd->cyclic = true;
1650 	txd->cctl |= PL080_CONTROL_TC_IRQ_EN;
1651 	for (tmp = 0; tmp < buf_len; tmp += period_len) {
1652 		ret = pl08x_tx_add_sg(txd, direction, slave_addr,
1653 				      buf_addr + tmp, period_len);
1654 		if (ret) {
1655 			pl08x_release_mux(plchan);
1656 			pl08x_free_txd(pl08x, txd);
1657 			return NULL;
1658 		}
1659 	}
1660 
1661 	ret = pl08x_fill_llis_for_desc(plchan->host, txd);
1662 	if (!ret) {
1663 		pl08x_release_mux(plchan);
1664 		pl08x_free_txd(pl08x, txd);
1665 		return NULL;
1666 	}
1667 
1668 	return vchan_tx_prep(&plchan->vc, &txd->vd, flags);
1669 }
1670 
1671 static int pl08x_config(struct dma_chan *chan,
1672 			struct dma_slave_config *config)
1673 {
1674 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1675 	struct pl08x_driver_data *pl08x = plchan->host;
1676 
1677 	if (!plchan->slave)
1678 		return -EINVAL;
1679 
1680 	/* Reject definitely invalid configurations */
1681 	if (config->src_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES ||
1682 	    config->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES)
1683 		return -EINVAL;
1684 
1685 	if (config->device_fc && pl08x->vd->pl080s) {
1686 		dev_err(&pl08x->adev->dev,
1687 			"%s: PL080S does not support peripheral flow control\n",
1688 			__func__);
1689 		return -EINVAL;
1690 	}
1691 
1692 	plchan->cfg = *config;
1693 
1694 	return 0;
1695 }
1696 
1697 static int pl08x_terminate_all(struct dma_chan *chan)
1698 {
1699 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1700 	struct pl08x_driver_data *pl08x = plchan->host;
1701 	unsigned long flags;
1702 
1703 	spin_lock_irqsave(&plchan->vc.lock, flags);
1704 	if (!plchan->phychan && !plchan->at) {
1705 		spin_unlock_irqrestore(&plchan->vc.lock, flags);
1706 		return 0;
1707 	}
1708 
1709 	plchan->state = PL08X_CHAN_IDLE;
1710 
1711 	if (plchan->phychan) {
1712 		/*
1713 		 * Mark physical channel as free and free any slave
1714 		 * signal
1715 		 */
1716 		pl08x_phy_free(plchan);
1717 	}
1718 	/* Dequeue jobs and free LLIs */
1719 	if (plchan->at) {
1720 		pl08x_desc_free(&plchan->at->vd);
1721 		plchan->at = NULL;
1722 	}
1723 	/* Dequeue jobs not yet fired as well */
1724 	pl08x_free_txd_list(pl08x, plchan);
1725 
1726 	spin_unlock_irqrestore(&plchan->vc.lock, flags);
1727 
1728 	return 0;
1729 }
1730 
1731 static int pl08x_pause(struct dma_chan *chan)
1732 {
1733 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1734 	unsigned long flags;
1735 
1736 	/*
1737 	 * Anything succeeds on channels with no physical allocation and
1738 	 * no queued transfers.
1739 	 */
1740 	spin_lock_irqsave(&plchan->vc.lock, flags);
1741 	if (!plchan->phychan && !plchan->at) {
1742 		spin_unlock_irqrestore(&plchan->vc.lock, flags);
1743 		return 0;
1744 	}
1745 
1746 	pl08x_pause_phy_chan(plchan->phychan);
1747 	plchan->state = PL08X_CHAN_PAUSED;
1748 
1749 	spin_unlock_irqrestore(&plchan->vc.lock, flags);
1750 
1751 	return 0;
1752 }
1753 
1754 static int pl08x_resume(struct dma_chan *chan)
1755 {
1756 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1757 	unsigned long flags;
1758 
1759 	/*
1760 	 * Anything succeeds on channels with no physical allocation and
1761 	 * no queued transfers.
1762 	 */
1763 	spin_lock_irqsave(&plchan->vc.lock, flags);
1764 	if (!plchan->phychan && !plchan->at) {
1765 		spin_unlock_irqrestore(&plchan->vc.lock, flags);
1766 		return 0;
1767 	}
1768 
1769 	pl08x_resume_phy_chan(plchan->phychan);
1770 	plchan->state = PL08X_CHAN_RUNNING;
1771 
1772 	spin_unlock_irqrestore(&plchan->vc.lock, flags);
1773 
1774 	return 0;
1775 }
1776 
1777 bool pl08x_filter_id(struct dma_chan *chan, void *chan_id)
1778 {
1779 	struct pl08x_dma_chan *plchan;
1780 	char *name = chan_id;
1781 
1782 	/* Reject channels for devices not bound to this driver */
1783 	if (chan->device->dev->driver != &pl08x_amba_driver.drv)
1784 		return false;
1785 
1786 	plchan = to_pl08x_chan(chan);
1787 
1788 	/* Check that the channel is not taken! */
1789 	if (!strcmp(plchan->name, name))
1790 		return true;
1791 
1792 	return false;
1793 }
1794 EXPORT_SYMBOL_GPL(pl08x_filter_id);
1795 
1796 static bool pl08x_filter_fn(struct dma_chan *chan, void *chan_id)
1797 {
1798 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1799 
1800 	return plchan->cd == chan_id;
1801 }
1802 
1803 /*
1804  * Just check that the device is there and active
1805  * TODO: turn this bit on/off depending on the number of physical channels
1806  * actually used, if it is zero... well shut it off. That will save some
1807  * power. Cut the clock at the same time.
1808  */
1809 static void pl08x_ensure_on(struct pl08x_driver_data *pl08x)
1810 {
1811 	/* The Nomadik variant does not have the config register */
1812 	if (pl08x->vd->nomadik)
1813 		return;
1814 	writel(PL080_CONFIG_ENABLE, pl08x->base + PL080_CONFIG);
1815 }
1816 
1817 static irqreturn_t pl08x_irq(int irq, void *dev)
1818 {
1819 	struct pl08x_driver_data *pl08x = dev;
1820 	u32 mask = 0, err, tc, i;
1821 
1822 	/* check & clear - ERR & TC interrupts */
1823 	err = readl(pl08x->base + PL080_ERR_STATUS);
1824 	if (err) {
1825 		dev_err(&pl08x->adev->dev, "%s error interrupt, register value 0x%08x\n",
1826 			__func__, err);
1827 		writel(err, pl08x->base + PL080_ERR_CLEAR);
1828 	}
1829 	tc = readl(pl08x->base + PL080_TC_STATUS);
1830 	if (tc)
1831 		writel(tc, pl08x->base + PL080_TC_CLEAR);
1832 
1833 	if (!err && !tc)
1834 		return IRQ_NONE;
1835 
1836 	for (i = 0; i < pl08x->vd->channels; i++) {
1837 		if (((1 << i) & err) || ((1 << i) & tc)) {
1838 			/* Locate physical channel */
1839 			struct pl08x_phy_chan *phychan = &pl08x->phy_chans[i];
1840 			struct pl08x_dma_chan *plchan = phychan->serving;
1841 			struct pl08x_txd *tx;
1842 
1843 			if (!plchan) {
1844 				dev_err(&pl08x->adev->dev,
1845 					"%s Error TC interrupt on unused channel: 0x%08x\n",
1846 					__func__, i);
1847 				continue;
1848 			}
1849 
1850 			spin_lock(&plchan->vc.lock);
1851 			tx = plchan->at;
1852 			if (tx && tx->cyclic) {
1853 				vchan_cyclic_callback(&tx->vd);
1854 			} else if (tx) {
1855 				plchan->at = NULL;
1856 				/*
1857 				 * This descriptor is done, release its mux
1858 				 * reservation.
1859 				 */
1860 				pl08x_release_mux(plchan);
1861 				tx->done = true;
1862 				vchan_cookie_complete(&tx->vd);
1863 
1864 				/*
1865 				 * And start the next descriptor (if any),
1866 				 * otherwise free this channel.
1867 				 */
1868 				if (vchan_next_desc(&plchan->vc))
1869 					pl08x_start_next_txd(plchan);
1870 				else
1871 					pl08x_phy_free(plchan);
1872 			}
1873 			spin_unlock(&plchan->vc.lock);
1874 
1875 			mask |= (1 << i);
1876 		}
1877 	}
1878 
1879 	return mask ? IRQ_HANDLED : IRQ_NONE;
1880 }
1881 
1882 static void pl08x_dma_slave_init(struct pl08x_dma_chan *chan)
1883 {
1884 	chan->slave = true;
1885 	chan->name = chan->cd->bus_id;
1886 	chan->cfg.src_addr = chan->cd->addr;
1887 	chan->cfg.dst_addr = chan->cd->addr;
1888 }
1889 
1890 /*
1891  * Initialise the DMAC memcpy/slave channels.
1892  * Make a local wrapper to hold required data
1893  */
1894 static int pl08x_dma_init_virtual_channels(struct pl08x_driver_data *pl08x,
1895 		struct dma_device *dmadev, unsigned int channels, bool slave)
1896 {
1897 	struct pl08x_dma_chan *chan;
1898 	int i;
1899 
1900 	INIT_LIST_HEAD(&dmadev->channels);
1901 
1902 	/*
1903 	 * Register as many many memcpy as we have physical channels,
1904 	 * we won't always be able to use all but the code will have
1905 	 * to cope with that situation.
1906 	 */
1907 	for (i = 0; i < channels; i++) {
1908 		chan = kzalloc(sizeof(*chan), GFP_KERNEL);
1909 		if (!chan)
1910 			return -ENOMEM;
1911 
1912 		chan->host = pl08x;
1913 		chan->state = PL08X_CHAN_IDLE;
1914 		chan->signal = -1;
1915 
1916 		if (slave) {
1917 			chan->cd = &pl08x->pd->slave_channels[i];
1918 			/*
1919 			 * Some implementations have muxed signals, whereas some
1920 			 * use a mux in front of the signals and need dynamic
1921 			 * assignment of signals.
1922 			 */
1923 			chan->signal = i;
1924 			pl08x_dma_slave_init(chan);
1925 		} else {
1926 			chan->cd = &pl08x->pd->memcpy_channel;
1927 			chan->name = kasprintf(GFP_KERNEL, "memcpy%d", i);
1928 			if (!chan->name) {
1929 				kfree(chan);
1930 				return -ENOMEM;
1931 			}
1932 		}
1933 		dev_dbg(&pl08x->adev->dev,
1934 			 "initialize virtual channel \"%s\"\n",
1935 			 chan->name);
1936 
1937 		chan->vc.desc_free = pl08x_desc_free;
1938 		vchan_init(&chan->vc, dmadev);
1939 	}
1940 	dev_info(&pl08x->adev->dev, "initialized %d virtual %s channels\n",
1941 		 i, slave ? "slave" : "memcpy");
1942 	return i;
1943 }
1944 
1945 static void pl08x_free_virtual_channels(struct dma_device *dmadev)
1946 {
1947 	struct pl08x_dma_chan *chan = NULL;
1948 	struct pl08x_dma_chan *next;
1949 
1950 	list_for_each_entry_safe(chan,
1951 				 next, &dmadev->channels, vc.chan.device_node) {
1952 		list_del(&chan->vc.chan.device_node);
1953 		kfree(chan);
1954 	}
1955 }
1956 
1957 #ifdef CONFIG_DEBUG_FS
1958 static const char *pl08x_state_str(enum pl08x_dma_chan_state state)
1959 {
1960 	switch (state) {
1961 	case PL08X_CHAN_IDLE:
1962 		return "idle";
1963 	case PL08X_CHAN_RUNNING:
1964 		return "running";
1965 	case PL08X_CHAN_PAUSED:
1966 		return "paused";
1967 	case PL08X_CHAN_WAITING:
1968 		return "waiting";
1969 	default:
1970 		break;
1971 	}
1972 	return "UNKNOWN STATE";
1973 }
1974 
1975 static int pl08x_debugfs_show(struct seq_file *s, void *data)
1976 {
1977 	struct pl08x_driver_data *pl08x = s->private;
1978 	struct pl08x_dma_chan *chan;
1979 	struct pl08x_phy_chan *ch;
1980 	unsigned long flags;
1981 	int i;
1982 
1983 	seq_printf(s, "PL08x physical channels:\n");
1984 	seq_printf(s, "CHANNEL:\tUSER:\n");
1985 	seq_printf(s, "--------\t-----\n");
1986 	for (i = 0; i < pl08x->vd->channels; i++) {
1987 		struct pl08x_dma_chan *virt_chan;
1988 
1989 		ch = &pl08x->phy_chans[i];
1990 
1991 		spin_lock_irqsave(&ch->lock, flags);
1992 		virt_chan = ch->serving;
1993 
1994 		seq_printf(s, "%d\t\t%s%s\n",
1995 			   ch->id,
1996 			   virt_chan ? virt_chan->name : "(none)",
1997 			   ch->locked ? " LOCKED" : "");
1998 
1999 		spin_unlock_irqrestore(&ch->lock, flags);
2000 	}
2001 
2002 	seq_printf(s, "\nPL08x virtual memcpy channels:\n");
2003 	seq_printf(s, "CHANNEL:\tSTATE:\n");
2004 	seq_printf(s, "--------\t------\n");
2005 	list_for_each_entry(chan, &pl08x->memcpy.channels, vc.chan.device_node) {
2006 		seq_printf(s, "%s\t\t%s\n", chan->name,
2007 			   pl08x_state_str(chan->state));
2008 	}
2009 
2010 	seq_printf(s, "\nPL08x virtual slave channels:\n");
2011 	seq_printf(s, "CHANNEL:\tSTATE:\n");
2012 	seq_printf(s, "--------\t------\n");
2013 	list_for_each_entry(chan, &pl08x->slave.channels, vc.chan.device_node) {
2014 		seq_printf(s, "%s\t\t%s\n", chan->name,
2015 			   pl08x_state_str(chan->state));
2016 	}
2017 
2018 	return 0;
2019 }
2020 
2021 static int pl08x_debugfs_open(struct inode *inode, struct file *file)
2022 {
2023 	return single_open(file, pl08x_debugfs_show, inode->i_private);
2024 }
2025 
2026 static const struct file_operations pl08x_debugfs_operations = {
2027 	.open		= pl08x_debugfs_open,
2028 	.read		= seq_read,
2029 	.llseek		= seq_lseek,
2030 	.release	= single_release,
2031 };
2032 
2033 static void init_pl08x_debugfs(struct pl08x_driver_data *pl08x)
2034 {
2035 	/* Expose a simple debugfs interface to view all clocks */
2036 	(void) debugfs_create_file(dev_name(&pl08x->adev->dev),
2037 			S_IFREG | S_IRUGO, NULL, pl08x,
2038 			&pl08x_debugfs_operations);
2039 }
2040 
2041 #else
2042 static inline void init_pl08x_debugfs(struct pl08x_driver_data *pl08x)
2043 {
2044 }
2045 #endif
2046 
2047 #ifdef CONFIG_OF
2048 static struct dma_chan *pl08x_find_chan_id(struct pl08x_driver_data *pl08x,
2049 					 u32 id)
2050 {
2051 	struct pl08x_dma_chan *chan;
2052 
2053 	list_for_each_entry(chan, &pl08x->slave.channels, vc.chan.device_node) {
2054 		if (chan->signal == id)
2055 			return &chan->vc.chan;
2056 	}
2057 
2058 	return NULL;
2059 }
2060 
2061 static struct dma_chan *pl08x_of_xlate(struct of_phandle_args *dma_spec,
2062 				       struct of_dma *ofdma)
2063 {
2064 	struct pl08x_driver_data *pl08x = ofdma->of_dma_data;
2065 	struct dma_chan *dma_chan;
2066 	struct pl08x_dma_chan *plchan;
2067 
2068 	if (!pl08x)
2069 		return NULL;
2070 
2071 	if (dma_spec->args_count != 2) {
2072 		dev_err(&pl08x->adev->dev,
2073 			"DMA channel translation requires two cells\n");
2074 		return NULL;
2075 	}
2076 
2077 	dma_chan = pl08x_find_chan_id(pl08x, dma_spec->args[0]);
2078 	if (!dma_chan) {
2079 		dev_err(&pl08x->adev->dev,
2080 			"DMA slave channel not found\n");
2081 		return NULL;
2082 	}
2083 
2084 	plchan = to_pl08x_chan(dma_chan);
2085 	dev_dbg(&pl08x->adev->dev,
2086 		"translated channel for signal %d\n",
2087 		dma_spec->args[0]);
2088 
2089 	/* Augment channel data for applicable AHB buses */
2090 	plchan->cd->periph_buses = dma_spec->args[1];
2091 	return dma_get_slave_channel(dma_chan);
2092 }
2093 
2094 static int pl08x_of_probe(struct amba_device *adev,
2095 			  struct pl08x_driver_data *pl08x,
2096 			  struct device_node *np)
2097 {
2098 	struct pl08x_platform_data *pd;
2099 	struct pl08x_channel_data *chanp = NULL;
2100 	u32 cctl_memcpy = 0;
2101 	u32 val;
2102 	int ret;
2103 	int i;
2104 
2105 	pd = devm_kzalloc(&adev->dev, sizeof(*pd), GFP_KERNEL);
2106 	if (!pd)
2107 		return -ENOMEM;
2108 
2109 	/* Eligible bus masters for fetching LLIs */
2110 	if (of_property_read_bool(np, "lli-bus-interface-ahb1"))
2111 		pd->lli_buses |= PL08X_AHB1;
2112 	if (of_property_read_bool(np, "lli-bus-interface-ahb2"))
2113 		pd->lli_buses |= PL08X_AHB2;
2114 	if (!pd->lli_buses) {
2115 		dev_info(&adev->dev, "no bus masters for LLIs stated, assume all\n");
2116 		pd->lli_buses |= PL08X_AHB1 | PL08X_AHB2;
2117 	}
2118 
2119 	/* Eligible bus masters for memory access */
2120 	if (of_property_read_bool(np, "mem-bus-interface-ahb1"))
2121 		pd->mem_buses |= PL08X_AHB1;
2122 	if (of_property_read_bool(np, "mem-bus-interface-ahb2"))
2123 		pd->mem_buses |= PL08X_AHB2;
2124 	if (!pd->mem_buses) {
2125 		dev_info(&adev->dev, "no bus masters for memory stated, assume all\n");
2126 		pd->mem_buses |= PL08X_AHB1 | PL08X_AHB2;
2127 	}
2128 
2129 	/* Parse the memcpy channel properties */
2130 	ret = of_property_read_u32(np, "memcpy-burst-size", &val);
2131 	if (ret) {
2132 		dev_info(&adev->dev, "no memcpy burst size specified, using 1 byte\n");
2133 		val = 1;
2134 	}
2135 	switch (val) {
2136 	default:
2137 		dev_err(&adev->dev, "illegal burst size for memcpy, set to 1\n");
2138 		/* Fall through */
2139 	case 1:
2140 		cctl_memcpy |= PL080_BSIZE_1 << PL080_CONTROL_SB_SIZE_SHIFT |
2141 			       PL080_BSIZE_1 << PL080_CONTROL_DB_SIZE_SHIFT;
2142 		break;
2143 	case 4:
2144 		cctl_memcpy |= PL080_BSIZE_4 << PL080_CONTROL_SB_SIZE_SHIFT |
2145 			       PL080_BSIZE_4 << PL080_CONTROL_DB_SIZE_SHIFT;
2146 		break;
2147 	case 8:
2148 		cctl_memcpy |= PL080_BSIZE_8 << PL080_CONTROL_SB_SIZE_SHIFT |
2149 			       PL080_BSIZE_8 << PL080_CONTROL_DB_SIZE_SHIFT;
2150 		break;
2151 	case 16:
2152 		cctl_memcpy |= PL080_BSIZE_16 << PL080_CONTROL_SB_SIZE_SHIFT |
2153 			       PL080_BSIZE_16 << PL080_CONTROL_DB_SIZE_SHIFT;
2154 		break;
2155 	case 32:
2156 		cctl_memcpy |= PL080_BSIZE_32 << PL080_CONTROL_SB_SIZE_SHIFT |
2157 			       PL080_BSIZE_32 << PL080_CONTROL_DB_SIZE_SHIFT;
2158 		break;
2159 	case 64:
2160 		cctl_memcpy |= PL080_BSIZE_64 << PL080_CONTROL_SB_SIZE_SHIFT |
2161 			       PL080_BSIZE_64 << PL080_CONTROL_DB_SIZE_SHIFT;
2162 		break;
2163 	case 128:
2164 		cctl_memcpy |= PL080_BSIZE_128 << PL080_CONTROL_SB_SIZE_SHIFT |
2165 			       PL080_BSIZE_128 << PL080_CONTROL_DB_SIZE_SHIFT;
2166 		break;
2167 	case 256:
2168 		cctl_memcpy |= PL080_BSIZE_256 << PL080_CONTROL_SB_SIZE_SHIFT |
2169 			       PL080_BSIZE_256 << PL080_CONTROL_DB_SIZE_SHIFT;
2170 		break;
2171 	}
2172 
2173 	ret = of_property_read_u32(np, "memcpy-bus-width", &val);
2174 	if (ret) {
2175 		dev_info(&adev->dev, "no memcpy bus width specified, using 8 bits\n");
2176 		val = 8;
2177 	}
2178 	switch (val) {
2179 	default:
2180 		dev_err(&adev->dev, "illegal bus width for memcpy, set to 8 bits\n");
2181 		/* Fall through */
2182 	case 8:
2183 		cctl_memcpy |= PL080_WIDTH_8BIT << PL080_CONTROL_SWIDTH_SHIFT |
2184 			       PL080_WIDTH_8BIT << PL080_CONTROL_DWIDTH_SHIFT;
2185 		break;
2186 	case 16:
2187 		cctl_memcpy |= PL080_WIDTH_16BIT << PL080_CONTROL_SWIDTH_SHIFT |
2188 			       PL080_WIDTH_16BIT << PL080_CONTROL_DWIDTH_SHIFT;
2189 		break;
2190 	case 32:
2191 		cctl_memcpy |= PL080_WIDTH_32BIT << PL080_CONTROL_SWIDTH_SHIFT |
2192 			       PL080_WIDTH_32BIT << PL080_CONTROL_DWIDTH_SHIFT;
2193 		break;
2194 	}
2195 
2196 	/* This is currently the only thing making sense */
2197 	cctl_memcpy |= PL080_CONTROL_PROT_SYS;
2198 
2199 	/* Set up memcpy channel */
2200 	pd->memcpy_channel.bus_id = "memcpy";
2201 	pd->memcpy_channel.cctl_memcpy = cctl_memcpy;
2202 	/* Use the buses that can access memory, obviously */
2203 	pd->memcpy_channel.periph_buses = pd->mem_buses;
2204 
2205 	/*
2206 	 * Allocate channel data for all possible slave channels (one
2207 	 * for each possible signal), channels will then be allocated
2208 	 * for a device and have it's AHB interfaces set up at
2209 	 * translation time.
2210 	 */
2211 	chanp = devm_kcalloc(&adev->dev,
2212 			pl08x->vd->signals,
2213 			sizeof(struct pl08x_channel_data),
2214 			GFP_KERNEL);
2215 	if (!chanp)
2216 		return -ENOMEM;
2217 
2218 	pd->slave_channels = chanp;
2219 	for (i = 0; i < pl08x->vd->signals; i++) {
2220 		/* chanp->periph_buses will be assigned at translation */
2221 		chanp->bus_id = kasprintf(GFP_KERNEL, "slave%d", i);
2222 		chanp++;
2223 	}
2224 	pd->num_slave_channels = pl08x->vd->signals;
2225 
2226 	pl08x->pd = pd;
2227 
2228 	return of_dma_controller_register(adev->dev.of_node, pl08x_of_xlate,
2229 					  pl08x);
2230 }
2231 #else
2232 static inline int pl08x_of_probe(struct amba_device *adev,
2233 				 struct pl08x_driver_data *pl08x,
2234 				 struct device_node *np)
2235 {
2236 	return -EINVAL;
2237 }
2238 #endif
2239 
2240 static int pl08x_probe(struct amba_device *adev, const struct amba_id *id)
2241 {
2242 	struct pl08x_driver_data *pl08x;
2243 	const struct vendor_data *vd = id->data;
2244 	struct device_node *np = adev->dev.of_node;
2245 	u32 tsfr_size;
2246 	int ret = 0;
2247 	int i;
2248 
2249 	ret = amba_request_regions(adev, NULL);
2250 	if (ret)
2251 		return ret;
2252 
2253 	/* Ensure that we can do DMA */
2254 	ret = dma_set_mask_and_coherent(&adev->dev, DMA_BIT_MASK(32));
2255 	if (ret)
2256 		goto out_no_pl08x;
2257 
2258 	/* Create the driver state holder */
2259 	pl08x = kzalloc(sizeof(*pl08x), GFP_KERNEL);
2260 	if (!pl08x) {
2261 		ret = -ENOMEM;
2262 		goto out_no_pl08x;
2263 	}
2264 
2265 	/* Assign useful pointers to the driver state */
2266 	pl08x->adev = adev;
2267 	pl08x->vd = vd;
2268 
2269 	/* Initialize memcpy engine */
2270 	dma_cap_set(DMA_MEMCPY, pl08x->memcpy.cap_mask);
2271 	pl08x->memcpy.dev = &adev->dev;
2272 	pl08x->memcpy.device_free_chan_resources = pl08x_free_chan_resources;
2273 	pl08x->memcpy.device_prep_dma_memcpy = pl08x_prep_dma_memcpy;
2274 	pl08x->memcpy.device_prep_dma_interrupt = pl08x_prep_dma_interrupt;
2275 	pl08x->memcpy.device_tx_status = pl08x_dma_tx_status;
2276 	pl08x->memcpy.device_issue_pending = pl08x_issue_pending;
2277 	pl08x->memcpy.device_config = pl08x_config;
2278 	pl08x->memcpy.device_pause = pl08x_pause;
2279 	pl08x->memcpy.device_resume = pl08x_resume;
2280 	pl08x->memcpy.device_terminate_all = pl08x_terminate_all;
2281 	pl08x->memcpy.src_addr_widths = PL80X_DMA_BUSWIDTHS;
2282 	pl08x->memcpy.dst_addr_widths = PL80X_DMA_BUSWIDTHS;
2283 	pl08x->memcpy.directions = BIT(DMA_MEM_TO_MEM);
2284 	pl08x->memcpy.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
2285 
2286 	/* Initialize slave engine */
2287 	dma_cap_set(DMA_SLAVE, pl08x->slave.cap_mask);
2288 	dma_cap_set(DMA_CYCLIC, pl08x->slave.cap_mask);
2289 	pl08x->slave.dev = &adev->dev;
2290 	pl08x->slave.device_free_chan_resources = pl08x_free_chan_resources;
2291 	pl08x->slave.device_prep_dma_interrupt = pl08x_prep_dma_interrupt;
2292 	pl08x->slave.device_tx_status = pl08x_dma_tx_status;
2293 	pl08x->slave.device_issue_pending = pl08x_issue_pending;
2294 	pl08x->slave.device_prep_slave_sg = pl08x_prep_slave_sg;
2295 	pl08x->slave.device_prep_dma_cyclic = pl08x_prep_dma_cyclic;
2296 	pl08x->slave.device_config = pl08x_config;
2297 	pl08x->slave.device_pause = pl08x_pause;
2298 	pl08x->slave.device_resume = pl08x_resume;
2299 	pl08x->slave.device_terminate_all = pl08x_terminate_all;
2300 	pl08x->slave.src_addr_widths = PL80X_DMA_BUSWIDTHS;
2301 	pl08x->slave.dst_addr_widths = PL80X_DMA_BUSWIDTHS;
2302 	pl08x->slave.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
2303 	pl08x->slave.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
2304 
2305 	/* Get the platform data */
2306 	pl08x->pd = dev_get_platdata(&adev->dev);
2307 	if (!pl08x->pd) {
2308 		if (np) {
2309 			ret = pl08x_of_probe(adev, pl08x, np);
2310 			if (ret)
2311 				goto out_no_platdata;
2312 		} else {
2313 			dev_err(&adev->dev, "no platform data supplied\n");
2314 			ret = -EINVAL;
2315 			goto out_no_platdata;
2316 		}
2317 	} else {
2318 		pl08x->slave.filter.map = pl08x->pd->slave_map;
2319 		pl08x->slave.filter.mapcnt = pl08x->pd->slave_map_len;
2320 		pl08x->slave.filter.fn = pl08x_filter_fn;
2321 	}
2322 
2323 	/* By default, AHB1 only.  If dualmaster, from platform */
2324 	pl08x->lli_buses = PL08X_AHB1;
2325 	pl08x->mem_buses = PL08X_AHB1;
2326 	if (pl08x->vd->dualmaster) {
2327 		pl08x->lli_buses = pl08x->pd->lli_buses;
2328 		pl08x->mem_buses = pl08x->pd->mem_buses;
2329 	}
2330 
2331 	if (vd->pl080s)
2332 		pl08x->lli_words = PL080S_LLI_WORDS;
2333 	else
2334 		pl08x->lli_words = PL080_LLI_WORDS;
2335 	tsfr_size = MAX_NUM_TSFR_LLIS * pl08x->lli_words * sizeof(u32);
2336 
2337 	/* A DMA memory pool for LLIs, align on 1-byte boundary */
2338 	pl08x->pool = dma_pool_create(DRIVER_NAME, &pl08x->adev->dev,
2339 						tsfr_size, PL08X_ALIGN, 0);
2340 	if (!pl08x->pool) {
2341 		ret = -ENOMEM;
2342 		goto out_no_lli_pool;
2343 	}
2344 
2345 	pl08x->base = ioremap(adev->res.start, resource_size(&adev->res));
2346 	if (!pl08x->base) {
2347 		ret = -ENOMEM;
2348 		goto out_no_ioremap;
2349 	}
2350 
2351 	/* Turn on the PL08x */
2352 	pl08x_ensure_on(pl08x);
2353 
2354 	/* Attach the interrupt handler */
2355 	writel(0x000000FF, pl08x->base + PL080_ERR_CLEAR);
2356 	writel(0x000000FF, pl08x->base + PL080_TC_CLEAR);
2357 
2358 	ret = request_irq(adev->irq[0], pl08x_irq, 0, DRIVER_NAME, pl08x);
2359 	if (ret) {
2360 		dev_err(&adev->dev, "%s failed to request interrupt %d\n",
2361 			__func__, adev->irq[0]);
2362 		goto out_no_irq;
2363 	}
2364 
2365 	/* Initialize physical channels */
2366 	pl08x->phy_chans = kzalloc((vd->channels * sizeof(*pl08x->phy_chans)),
2367 			GFP_KERNEL);
2368 	if (!pl08x->phy_chans) {
2369 		ret = -ENOMEM;
2370 		goto out_no_phychans;
2371 	}
2372 
2373 	for (i = 0; i < vd->channels; i++) {
2374 		struct pl08x_phy_chan *ch = &pl08x->phy_chans[i];
2375 
2376 		ch->id = i;
2377 		ch->base = pl08x->base + PL080_Cx_BASE(i);
2378 		ch->reg_config = ch->base + vd->config_offset;
2379 		spin_lock_init(&ch->lock);
2380 
2381 		/*
2382 		 * Nomadik variants can have channels that are locked
2383 		 * down for the secure world only. Lock up these channels
2384 		 * by perpetually serving a dummy virtual channel.
2385 		 */
2386 		if (vd->nomadik) {
2387 			u32 val;
2388 
2389 			val = readl(ch->reg_config);
2390 			if (val & (PL080N_CONFIG_ITPROT | PL080N_CONFIG_SECPROT)) {
2391 				dev_info(&adev->dev, "physical channel %d reserved for secure access only\n", i);
2392 				ch->locked = true;
2393 			}
2394 		}
2395 
2396 		dev_dbg(&adev->dev, "physical channel %d is %s\n",
2397 			i, pl08x_phy_channel_busy(ch) ? "BUSY" : "FREE");
2398 	}
2399 
2400 	/* Register as many memcpy channels as there are physical channels */
2401 	ret = pl08x_dma_init_virtual_channels(pl08x, &pl08x->memcpy,
2402 					      pl08x->vd->channels, false);
2403 	if (ret <= 0) {
2404 		dev_warn(&pl08x->adev->dev,
2405 			 "%s failed to enumerate memcpy channels - %d\n",
2406 			 __func__, ret);
2407 		goto out_no_memcpy;
2408 	}
2409 
2410 	/* Register slave channels */
2411 	ret = pl08x_dma_init_virtual_channels(pl08x, &pl08x->slave,
2412 			pl08x->pd->num_slave_channels, true);
2413 	if (ret < 0) {
2414 		dev_warn(&pl08x->adev->dev,
2415 			"%s failed to enumerate slave channels - %d\n",
2416 				__func__, ret);
2417 		goto out_no_slave;
2418 	}
2419 
2420 	ret = dma_async_device_register(&pl08x->memcpy);
2421 	if (ret) {
2422 		dev_warn(&pl08x->adev->dev,
2423 			"%s failed to register memcpy as an async device - %d\n",
2424 			__func__, ret);
2425 		goto out_no_memcpy_reg;
2426 	}
2427 
2428 	ret = dma_async_device_register(&pl08x->slave);
2429 	if (ret) {
2430 		dev_warn(&pl08x->adev->dev,
2431 			"%s failed to register slave as an async device - %d\n",
2432 			__func__, ret);
2433 		goto out_no_slave_reg;
2434 	}
2435 
2436 	amba_set_drvdata(adev, pl08x);
2437 	init_pl08x_debugfs(pl08x);
2438 	dev_info(&pl08x->adev->dev, "DMA: PL%03x%s rev%u at 0x%08llx irq %d\n",
2439 		 amba_part(adev), pl08x->vd->pl080s ? "s" : "", amba_rev(adev),
2440 		 (unsigned long long)adev->res.start, adev->irq[0]);
2441 
2442 	return 0;
2443 
2444 out_no_slave_reg:
2445 	dma_async_device_unregister(&pl08x->memcpy);
2446 out_no_memcpy_reg:
2447 	pl08x_free_virtual_channels(&pl08x->slave);
2448 out_no_slave:
2449 	pl08x_free_virtual_channels(&pl08x->memcpy);
2450 out_no_memcpy:
2451 	kfree(pl08x->phy_chans);
2452 out_no_phychans:
2453 	free_irq(adev->irq[0], pl08x);
2454 out_no_irq:
2455 	iounmap(pl08x->base);
2456 out_no_ioremap:
2457 	dma_pool_destroy(pl08x->pool);
2458 out_no_lli_pool:
2459 out_no_platdata:
2460 	kfree(pl08x);
2461 out_no_pl08x:
2462 	amba_release_regions(adev);
2463 	return ret;
2464 }
2465 
2466 /* PL080 has 8 channels and the PL080 have just 2 */
2467 static struct vendor_data vendor_pl080 = {
2468 	.config_offset = PL080_CH_CONFIG,
2469 	.channels = 8,
2470 	.signals = 16,
2471 	.dualmaster = true,
2472 	.max_transfer_size = PL080_CONTROL_TRANSFER_SIZE_MASK,
2473 };
2474 
2475 static struct vendor_data vendor_nomadik = {
2476 	.config_offset = PL080_CH_CONFIG,
2477 	.channels = 8,
2478 	.signals = 32,
2479 	.dualmaster = true,
2480 	.nomadik = true,
2481 	.max_transfer_size = PL080_CONTROL_TRANSFER_SIZE_MASK,
2482 };
2483 
2484 static struct vendor_data vendor_pl080s = {
2485 	.config_offset = PL080S_CH_CONFIG,
2486 	.channels = 8,
2487 	.signals = 32,
2488 	.pl080s = true,
2489 	.max_transfer_size = PL080S_CONTROL_TRANSFER_SIZE_MASK,
2490 };
2491 
2492 static struct vendor_data vendor_pl081 = {
2493 	.config_offset = PL080_CH_CONFIG,
2494 	.channels = 2,
2495 	.signals = 16,
2496 	.dualmaster = false,
2497 	.max_transfer_size = PL080_CONTROL_TRANSFER_SIZE_MASK,
2498 };
2499 
2500 static struct amba_id pl08x_ids[] = {
2501 	/* Samsung PL080S variant */
2502 	{
2503 		.id	= 0x0a141080,
2504 		.mask	= 0xffffffff,
2505 		.data	= &vendor_pl080s,
2506 	},
2507 	/* PL080 */
2508 	{
2509 		.id	= 0x00041080,
2510 		.mask	= 0x000fffff,
2511 		.data	= &vendor_pl080,
2512 	},
2513 	/* PL081 */
2514 	{
2515 		.id	= 0x00041081,
2516 		.mask	= 0x000fffff,
2517 		.data	= &vendor_pl081,
2518 	},
2519 	/* Nomadik 8815 PL080 variant */
2520 	{
2521 		.id	= 0x00280080,
2522 		.mask	= 0x00ffffff,
2523 		.data	= &vendor_nomadik,
2524 	},
2525 	{ 0, 0 },
2526 };
2527 
2528 MODULE_DEVICE_TABLE(amba, pl08x_ids);
2529 
2530 static struct amba_driver pl08x_amba_driver = {
2531 	.drv.name	= DRIVER_NAME,
2532 	.id_table	= pl08x_ids,
2533 	.probe		= pl08x_probe,
2534 };
2535 
2536 static int __init pl08x_init(void)
2537 {
2538 	int retval;
2539 	retval = amba_driver_register(&pl08x_amba_driver);
2540 	if (retval)
2541 		printk(KERN_WARNING DRIVER_NAME
2542 		       "failed to register as an AMBA device (%d)\n",
2543 		       retval);
2544 	return retval;
2545 }
2546 subsys_initcall(pl08x_init);
2547