xref: /openbmc/linux/drivers/dma/amba-pl08x.c (revision a36954f5)
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  * @config_offset: offset to the configuration register
110  * @channels: the number of channels available in this variant
111  * @signals: the number of request signals available from the hardware
112  * @dualmaster: whether this version supports dual AHB masters or not.
113  * @nomadik: whether the channels have Nomadik security extension bits
114  *	that need to be checked for permission before use and some registers are
115  *	missing
116  * @pl080s: whether this version is a PL080S, which has separate register and
117  *	LLI word for transfer size.
118  * @max_transfer_size: the maximum single element transfer size for this
119  *	PL08x variant.
120  */
121 struct vendor_data {
122 	u8 config_offset;
123 	u8 channels;
124 	u8 signals;
125 	bool dualmaster;
126 	bool nomadik;
127 	bool pl080s;
128 	u32 max_transfer_size;
129 };
130 
131 /**
132  * struct pl08x_bus_data - information of source or destination
133  * busses for a transfer
134  * @addr: current address
135  * @maxwidth: the maximum width of a transfer on this bus
136  * @buswidth: the width of this bus in bytes: 1, 2 or 4
137  */
138 struct pl08x_bus_data {
139 	dma_addr_t addr;
140 	u8 maxwidth;
141 	u8 buswidth;
142 };
143 
144 #define IS_BUS_ALIGNED(bus) IS_ALIGNED((bus)->addr, (bus)->buswidth)
145 
146 /**
147  * struct pl08x_phy_chan - holder for the physical channels
148  * @id: physical index to this channel
149  * @base: memory base address for this physical channel
150  * @reg_config: configuration address for this physical channel
151  * @lock: a lock to use when altering an instance of this struct
152  * @serving: the virtual channel currently being served by this physical
153  * channel
154  * @locked: channel unavailable for the system, e.g. dedicated to secure
155  * world
156  */
157 struct pl08x_phy_chan {
158 	unsigned int id;
159 	void __iomem *base;
160 	void __iomem *reg_config;
161 	spinlock_t lock;
162 	struct pl08x_dma_chan *serving;
163 	bool locked;
164 };
165 
166 /**
167  * struct pl08x_sg - structure containing data per sg
168  * @src_addr: src address of sg
169  * @dst_addr: dst address of sg
170  * @len: transfer len in bytes
171  * @node: node for txd's dsg_list
172  */
173 struct pl08x_sg {
174 	dma_addr_t src_addr;
175 	dma_addr_t dst_addr;
176 	size_t len;
177 	struct list_head node;
178 };
179 
180 /**
181  * struct pl08x_txd - wrapper for struct dma_async_tx_descriptor
182  * @vd: virtual DMA descriptor
183  * @dsg_list: list of children sg's
184  * @llis_bus: DMA memory address (physical) start for the LLIs
185  * @llis_va: virtual memory address start for the LLIs
186  * @cctl: control reg values for current txd
187  * @ccfg: config reg values for current txd
188  * @done: this marks completed descriptors, which should not have their
189  *   mux released.
190  * @cyclic: indicate cyclic transfers
191  */
192 struct pl08x_txd {
193 	struct virt_dma_desc vd;
194 	struct list_head dsg_list;
195 	dma_addr_t llis_bus;
196 	u32 *llis_va;
197 	/* Default cctl value for LLIs */
198 	u32 cctl;
199 	/*
200 	 * Settings to be put into the physical channel when we
201 	 * trigger this txd.  Other registers are in llis_va[0].
202 	 */
203 	u32 ccfg;
204 	bool done;
205 	bool cyclic;
206 };
207 
208 /**
209  * enum pl08x_dma_chan_state - holds the PL08x specific virtual channel
210  * states
211  * @PL08X_CHAN_IDLE: the channel is idle
212  * @PL08X_CHAN_RUNNING: the channel has allocated a physical transport
213  * channel and is running a transfer on it
214  * @PL08X_CHAN_PAUSED: the channel has allocated a physical transport
215  * channel, but the transfer is currently paused
216  * @PL08X_CHAN_WAITING: the channel is waiting for a physical transport
217  * channel to become available (only pertains to memcpy channels)
218  */
219 enum pl08x_dma_chan_state {
220 	PL08X_CHAN_IDLE,
221 	PL08X_CHAN_RUNNING,
222 	PL08X_CHAN_PAUSED,
223 	PL08X_CHAN_WAITING,
224 };
225 
226 /**
227  * struct pl08x_dma_chan - this structure wraps a DMA ENGINE channel
228  * @vc: wrappped virtual channel
229  * @phychan: the physical channel utilized by this channel, if there is one
230  * @name: name of channel
231  * @cd: channel platform data
232  * @cfg: slave configuration
233  * @at: active transaction on this channel
234  * @host: a pointer to the host (internal use)
235  * @state: whether the channel is idle, paused, running etc
236  * @slave: whether this channel is a device (slave) or for memcpy
237  * @signal: the physical DMA request signal which this channel is using
238  * @mux_use: count of descriptors using this DMA request signal setting
239  */
240 struct pl08x_dma_chan {
241 	struct virt_dma_chan vc;
242 	struct pl08x_phy_chan *phychan;
243 	const char *name;
244 	struct pl08x_channel_data *cd;
245 	struct dma_slave_config cfg;
246 	struct pl08x_txd *at;
247 	struct pl08x_driver_data *host;
248 	enum pl08x_dma_chan_state state;
249 	bool slave;
250 	int signal;
251 	unsigned mux_use;
252 };
253 
254 /**
255  * struct pl08x_driver_data - the local state holder for the PL08x
256  * @slave: slave engine for this instance
257  * @memcpy: memcpy engine for this instance
258  * @base: virtual memory base (remapped) for the PL08x
259  * @adev: the corresponding AMBA (PrimeCell) bus entry
260  * @vd: vendor data for this PL08x variant
261  * @pd: platform data passed in from the platform/machine
262  * @phy_chans: array of data for the physical channels
263  * @pool: a pool for the LLI descriptors
264  * @lli_buses: bitmask to or in to LLI pointer selecting AHB port for LLI
265  * fetches
266  * @mem_buses: set to indicate memory transfers on AHB2.
267  * @lli_words: how many words are used in each LLI item for this variant
268  */
269 struct pl08x_driver_data {
270 	struct dma_device slave;
271 	struct dma_device memcpy;
272 	void __iomem *base;
273 	struct amba_device *adev;
274 	const struct vendor_data *vd;
275 	struct pl08x_platform_data *pd;
276 	struct pl08x_phy_chan *phy_chans;
277 	struct dma_pool *pool;
278 	u8 lli_buses;
279 	u8 mem_buses;
280 	u8 lli_words;
281 };
282 
283 /*
284  * PL08X specific defines
285  */
286 
287 /* The order of words in an LLI. */
288 #define PL080_LLI_SRC		0
289 #define PL080_LLI_DST		1
290 #define PL080_LLI_LLI		2
291 #define PL080_LLI_CCTL		3
292 #define PL080S_LLI_CCTL2	4
293 
294 /* Total words in an LLI. */
295 #define PL080_LLI_WORDS		4
296 #define PL080S_LLI_WORDS	8
297 
298 /*
299  * Number of LLIs in each LLI buffer allocated for one transfer
300  * (maximum times we call dma_pool_alloc on this pool without freeing)
301  */
302 #define MAX_NUM_TSFR_LLIS	512
303 #define PL08X_ALIGN		8
304 
305 static inline struct pl08x_dma_chan *to_pl08x_chan(struct dma_chan *chan)
306 {
307 	return container_of(chan, struct pl08x_dma_chan, vc.chan);
308 }
309 
310 static inline struct pl08x_txd *to_pl08x_txd(struct dma_async_tx_descriptor *tx)
311 {
312 	return container_of(tx, struct pl08x_txd, vd.tx);
313 }
314 
315 /*
316  * Mux handling.
317  *
318  * This gives us the DMA request input to the PL08x primecell which the
319  * peripheral described by the channel data will be routed to, possibly
320  * via a board/SoC specific external MUX.  One important point to note
321  * here is that this does not depend on the physical channel.
322  */
323 static int pl08x_request_mux(struct pl08x_dma_chan *plchan)
324 {
325 	const struct pl08x_platform_data *pd = plchan->host->pd;
326 	int ret;
327 
328 	if (plchan->mux_use++ == 0 && pd->get_xfer_signal) {
329 		ret = pd->get_xfer_signal(plchan->cd);
330 		if (ret < 0) {
331 			plchan->mux_use = 0;
332 			return ret;
333 		}
334 
335 		plchan->signal = ret;
336 	}
337 	return 0;
338 }
339 
340 static void pl08x_release_mux(struct pl08x_dma_chan *plchan)
341 {
342 	const struct pl08x_platform_data *pd = plchan->host->pd;
343 
344 	if (plchan->signal >= 0) {
345 		WARN_ON(plchan->mux_use == 0);
346 
347 		if (--plchan->mux_use == 0 && pd->put_xfer_signal) {
348 			pd->put_xfer_signal(plchan->cd, plchan->signal);
349 			plchan->signal = -1;
350 		}
351 	}
352 }
353 
354 /*
355  * Physical channel handling
356  */
357 
358 /* Whether a certain channel is busy or not */
359 static int pl08x_phy_channel_busy(struct pl08x_phy_chan *ch)
360 {
361 	unsigned int val;
362 
363 	val = readl(ch->reg_config);
364 	return val & PL080_CONFIG_ACTIVE;
365 }
366 
367 static void pl08x_write_lli(struct pl08x_driver_data *pl08x,
368 		struct pl08x_phy_chan *phychan, const u32 *lli, u32 ccfg)
369 {
370 	if (pl08x->vd->pl080s)
371 		dev_vdbg(&pl08x->adev->dev,
372 			"WRITE channel %d: csrc=0x%08x, cdst=0x%08x, "
373 			"clli=0x%08x, cctl=0x%08x, cctl2=0x%08x, ccfg=0x%08x\n",
374 			phychan->id, lli[PL080_LLI_SRC], lli[PL080_LLI_DST],
375 			lli[PL080_LLI_LLI], lli[PL080_LLI_CCTL],
376 			lli[PL080S_LLI_CCTL2], ccfg);
377 	else
378 		dev_vdbg(&pl08x->adev->dev,
379 			"WRITE channel %d: csrc=0x%08x, cdst=0x%08x, "
380 			"clli=0x%08x, cctl=0x%08x, ccfg=0x%08x\n",
381 			phychan->id, lli[PL080_LLI_SRC], lli[PL080_LLI_DST],
382 			lli[PL080_LLI_LLI], lli[PL080_LLI_CCTL], ccfg);
383 
384 	writel_relaxed(lli[PL080_LLI_SRC], phychan->base + PL080_CH_SRC_ADDR);
385 	writel_relaxed(lli[PL080_LLI_DST], phychan->base + PL080_CH_DST_ADDR);
386 	writel_relaxed(lli[PL080_LLI_LLI], phychan->base + PL080_CH_LLI);
387 	writel_relaxed(lli[PL080_LLI_CCTL], phychan->base + PL080_CH_CONTROL);
388 
389 	if (pl08x->vd->pl080s)
390 		writel_relaxed(lli[PL080S_LLI_CCTL2],
391 				phychan->base + PL080S_CH_CONTROL2);
392 
393 	writel(ccfg, phychan->reg_config);
394 }
395 
396 /*
397  * Set the initial DMA register values i.e. those for the first LLI
398  * The next LLI pointer and the configuration interrupt bit have
399  * been set when the LLIs were constructed.  Poke them into the hardware
400  * and start the transfer.
401  */
402 static void pl08x_start_next_txd(struct pl08x_dma_chan *plchan)
403 {
404 	struct pl08x_driver_data *pl08x = plchan->host;
405 	struct pl08x_phy_chan *phychan = plchan->phychan;
406 	struct virt_dma_desc *vd = vchan_next_desc(&plchan->vc);
407 	struct pl08x_txd *txd = to_pl08x_txd(&vd->tx);
408 	u32 val;
409 
410 	list_del(&txd->vd.node);
411 
412 	plchan->at = txd;
413 
414 	/* Wait for channel inactive */
415 	while (pl08x_phy_channel_busy(phychan))
416 		cpu_relax();
417 
418 	pl08x_write_lli(pl08x, phychan, &txd->llis_va[0], txd->ccfg);
419 
420 	/* Enable the DMA channel */
421 	/* Do not access config register until channel shows as disabled */
422 	while (readl(pl08x->base + PL080_EN_CHAN) & BIT(phychan->id))
423 		cpu_relax();
424 
425 	/* Do not access config register until channel shows as inactive */
426 	val = readl(phychan->reg_config);
427 	while ((val & PL080_CONFIG_ACTIVE) || (val & PL080_CONFIG_ENABLE))
428 		val = readl(phychan->reg_config);
429 
430 	writel(val | PL080_CONFIG_ENABLE, phychan->reg_config);
431 }
432 
433 /*
434  * Pause the channel by setting the HALT bit.
435  *
436  * For M->P transfers, pause the DMAC first and then stop the peripheral -
437  * the FIFO can only drain if the peripheral is still requesting data.
438  * (note: this can still timeout if the DMAC FIFO never drains of data.)
439  *
440  * For P->M transfers, disable the peripheral first to stop it filling
441  * the DMAC FIFO, and then pause the DMAC.
442  */
443 static void pl08x_pause_phy_chan(struct pl08x_phy_chan *ch)
444 {
445 	u32 val;
446 	int timeout;
447 
448 	/* Set the HALT bit and wait for the FIFO to drain */
449 	val = readl(ch->reg_config);
450 	val |= PL080_CONFIG_HALT;
451 	writel(val, ch->reg_config);
452 
453 	/* Wait for channel inactive */
454 	for (timeout = 1000; timeout; timeout--) {
455 		if (!pl08x_phy_channel_busy(ch))
456 			break;
457 		udelay(1);
458 	}
459 	if (pl08x_phy_channel_busy(ch))
460 		pr_err("pl08x: channel%u timeout waiting for pause\n", ch->id);
461 }
462 
463 static void pl08x_resume_phy_chan(struct pl08x_phy_chan *ch)
464 {
465 	u32 val;
466 
467 	/* Clear the HALT bit */
468 	val = readl(ch->reg_config);
469 	val &= ~PL080_CONFIG_HALT;
470 	writel(val, ch->reg_config);
471 }
472 
473 /*
474  * pl08x_terminate_phy_chan() stops the channel, clears the FIFO and
475  * clears any pending interrupt status.  This should not be used for
476  * an on-going transfer, but as a method of shutting down a channel
477  * (eg, when it's no longer used) or terminating a transfer.
478  */
479 static void pl08x_terminate_phy_chan(struct pl08x_driver_data *pl08x,
480 	struct pl08x_phy_chan *ch)
481 {
482 	u32 val = readl(ch->reg_config);
483 
484 	val &= ~(PL080_CONFIG_ENABLE | PL080_CONFIG_ERR_IRQ_MASK |
485 		 PL080_CONFIG_TC_IRQ_MASK);
486 
487 	writel(val, ch->reg_config);
488 
489 	writel(BIT(ch->id), pl08x->base + PL080_ERR_CLEAR);
490 	writel(BIT(ch->id), pl08x->base + PL080_TC_CLEAR);
491 }
492 
493 static inline u32 get_bytes_in_cctl(u32 cctl)
494 {
495 	/* The source width defines the number of bytes */
496 	u32 bytes = cctl & PL080_CONTROL_TRANSFER_SIZE_MASK;
497 
498 	cctl &= PL080_CONTROL_SWIDTH_MASK;
499 
500 	switch (cctl >> PL080_CONTROL_SWIDTH_SHIFT) {
501 	case PL080_WIDTH_8BIT:
502 		break;
503 	case PL080_WIDTH_16BIT:
504 		bytes *= 2;
505 		break;
506 	case PL080_WIDTH_32BIT:
507 		bytes *= 4;
508 		break;
509 	}
510 	return bytes;
511 }
512 
513 static inline u32 get_bytes_in_cctl_pl080s(u32 cctl, u32 cctl1)
514 {
515 	/* The source width defines the number of bytes */
516 	u32 bytes = cctl1 & PL080S_CONTROL_TRANSFER_SIZE_MASK;
517 
518 	cctl &= PL080_CONTROL_SWIDTH_MASK;
519 
520 	switch (cctl >> PL080_CONTROL_SWIDTH_SHIFT) {
521 	case PL080_WIDTH_8BIT:
522 		break;
523 	case PL080_WIDTH_16BIT:
524 		bytes *= 2;
525 		break;
526 	case PL080_WIDTH_32BIT:
527 		bytes *= 4;
528 		break;
529 	}
530 	return bytes;
531 }
532 
533 /* The channel should be paused when calling this */
534 static u32 pl08x_getbytes_chan(struct pl08x_dma_chan *plchan)
535 {
536 	struct pl08x_driver_data *pl08x = plchan->host;
537 	const u32 *llis_va, *llis_va_limit;
538 	struct pl08x_phy_chan *ch;
539 	dma_addr_t llis_bus;
540 	struct pl08x_txd *txd;
541 	u32 llis_max_words;
542 	size_t bytes;
543 	u32 clli;
544 
545 	ch = plchan->phychan;
546 	txd = plchan->at;
547 
548 	if (!ch || !txd)
549 		return 0;
550 
551 	/*
552 	 * Follow the LLIs to get the number of remaining
553 	 * bytes in the currently active transaction.
554 	 */
555 	clli = readl(ch->base + PL080_CH_LLI) & ~PL080_LLI_LM_AHB2;
556 
557 	/* First get the remaining bytes in the active transfer */
558 	if (pl08x->vd->pl080s)
559 		bytes = get_bytes_in_cctl_pl080s(
560 				readl(ch->base + PL080_CH_CONTROL),
561 				readl(ch->base + PL080S_CH_CONTROL2));
562 	else
563 		bytes = get_bytes_in_cctl(readl(ch->base + PL080_CH_CONTROL));
564 
565 	if (!clli)
566 		return bytes;
567 
568 	llis_va = txd->llis_va;
569 	llis_bus = txd->llis_bus;
570 
571 	llis_max_words = pl08x->lli_words * MAX_NUM_TSFR_LLIS;
572 	BUG_ON(clli < llis_bus || clli >= llis_bus +
573 						sizeof(u32) * llis_max_words);
574 
575 	/*
576 	 * Locate the next LLI - as this is an array,
577 	 * it's simple maths to find.
578 	 */
579 	llis_va += (clli - llis_bus) / sizeof(u32);
580 
581 	llis_va_limit = llis_va + llis_max_words;
582 
583 	for (; llis_va < llis_va_limit; llis_va += pl08x->lli_words) {
584 		if (pl08x->vd->pl080s)
585 			bytes += get_bytes_in_cctl_pl080s(
586 						llis_va[PL080_LLI_CCTL],
587 						llis_va[PL080S_LLI_CCTL2]);
588 		else
589 			bytes += get_bytes_in_cctl(llis_va[PL080_LLI_CCTL]);
590 
591 		/*
592 		 * A LLI pointer going backward terminates the LLI list
593 		 */
594 		if (llis_va[PL080_LLI_LLI] <= clli)
595 			break;
596 	}
597 
598 	return bytes;
599 }
600 
601 /*
602  * Allocate a physical channel for a virtual channel
603  *
604  * Try to locate a physical channel to be used for this transfer. If all
605  * are taken return NULL and the requester will have to cope by using
606  * some fallback PIO mode or retrying later.
607  */
608 static struct pl08x_phy_chan *
609 pl08x_get_phy_channel(struct pl08x_driver_data *pl08x,
610 		      struct pl08x_dma_chan *virt_chan)
611 {
612 	struct pl08x_phy_chan *ch = NULL;
613 	unsigned long flags;
614 	int i;
615 
616 	for (i = 0; i < pl08x->vd->channels; i++) {
617 		ch = &pl08x->phy_chans[i];
618 
619 		spin_lock_irqsave(&ch->lock, flags);
620 
621 		if (!ch->locked && !ch->serving) {
622 			ch->serving = virt_chan;
623 			spin_unlock_irqrestore(&ch->lock, flags);
624 			break;
625 		}
626 
627 		spin_unlock_irqrestore(&ch->lock, flags);
628 	}
629 
630 	if (i == pl08x->vd->channels) {
631 		/* No physical channel available, cope with it */
632 		return NULL;
633 	}
634 
635 	return ch;
636 }
637 
638 /* Mark the physical channel as free.  Note, this write is atomic. */
639 static inline void pl08x_put_phy_channel(struct pl08x_driver_data *pl08x,
640 					 struct pl08x_phy_chan *ch)
641 {
642 	ch->serving = NULL;
643 }
644 
645 /*
646  * Try to allocate a physical channel.  When successful, assign it to
647  * this virtual channel, and initiate the next descriptor.  The
648  * virtual channel lock must be held at this point.
649  */
650 static void pl08x_phy_alloc_and_start(struct pl08x_dma_chan *plchan)
651 {
652 	struct pl08x_driver_data *pl08x = plchan->host;
653 	struct pl08x_phy_chan *ch;
654 
655 	ch = pl08x_get_phy_channel(pl08x, plchan);
656 	if (!ch) {
657 		dev_dbg(&pl08x->adev->dev, "no physical channel available for xfer on %s\n", plchan->name);
658 		plchan->state = PL08X_CHAN_WAITING;
659 		return;
660 	}
661 
662 	dev_dbg(&pl08x->adev->dev, "allocated physical channel %d for xfer on %s\n",
663 		ch->id, plchan->name);
664 
665 	plchan->phychan = ch;
666 	plchan->state = PL08X_CHAN_RUNNING;
667 	pl08x_start_next_txd(plchan);
668 }
669 
670 static void pl08x_phy_reassign_start(struct pl08x_phy_chan *ch,
671 	struct pl08x_dma_chan *plchan)
672 {
673 	struct pl08x_driver_data *pl08x = plchan->host;
674 
675 	dev_dbg(&pl08x->adev->dev, "reassigned physical channel %d for xfer on %s\n",
676 		ch->id, plchan->name);
677 
678 	/*
679 	 * We do this without taking the lock; we're really only concerned
680 	 * about whether this pointer is NULL or not, and we're guaranteed
681 	 * that this will only be called when it _already_ is non-NULL.
682 	 */
683 	ch->serving = plchan;
684 	plchan->phychan = ch;
685 	plchan->state = PL08X_CHAN_RUNNING;
686 	pl08x_start_next_txd(plchan);
687 }
688 
689 /*
690  * Free a physical DMA channel, potentially reallocating it to another
691  * virtual channel if we have any pending.
692  */
693 static void pl08x_phy_free(struct pl08x_dma_chan *plchan)
694 {
695 	struct pl08x_driver_data *pl08x = plchan->host;
696 	struct pl08x_dma_chan *p, *next;
697 
698  retry:
699 	next = NULL;
700 
701 	/* Find a waiting virtual channel for the next transfer. */
702 	list_for_each_entry(p, &pl08x->memcpy.channels, vc.chan.device_node)
703 		if (p->state == PL08X_CHAN_WAITING) {
704 			next = p;
705 			break;
706 		}
707 
708 	if (!next) {
709 		list_for_each_entry(p, &pl08x->slave.channels, vc.chan.device_node)
710 			if (p->state == PL08X_CHAN_WAITING) {
711 				next = p;
712 				break;
713 			}
714 	}
715 
716 	/* Ensure that the physical channel is stopped */
717 	pl08x_terminate_phy_chan(pl08x, plchan->phychan);
718 
719 	if (next) {
720 		bool success;
721 
722 		/*
723 		 * Eww.  We know this isn't going to deadlock
724 		 * but lockdep probably doesn't.
725 		 */
726 		spin_lock(&next->vc.lock);
727 		/* Re-check the state now that we have the lock */
728 		success = next->state == PL08X_CHAN_WAITING;
729 		if (success)
730 			pl08x_phy_reassign_start(plchan->phychan, next);
731 		spin_unlock(&next->vc.lock);
732 
733 		/* If the state changed, try to find another channel */
734 		if (!success)
735 			goto retry;
736 	} else {
737 		/* No more jobs, so free up the physical channel */
738 		pl08x_put_phy_channel(pl08x, plchan->phychan);
739 	}
740 
741 	plchan->phychan = NULL;
742 	plchan->state = PL08X_CHAN_IDLE;
743 }
744 
745 /*
746  * LLI handling
747  */
748 
749 static inline unsigned int pl08x_get_bytes_for_cctl(unsigned int coded)
750 {
751 	switch (coded) {
752 	case PL080_WIDTH_8BIT:
753 		return 1;
754 	case PL080_WIDTH_16BIT:
755 		return 2;
756 	case PL080_WIDTH_32BIT:
757 		return 4;
758 	default:
759 		break;
760 	}
761 	BUG();
762 	return 0;
763 }
764 
765 static inline u32 pl08x_cctl_bits(u32 cctl, u8 srcwidth, u8 dstwidth,
766 				  size_t tsize)
767 {
768 	u32 retbits = cctl;
769 
770 	/* Remove all src, dst and transfer size bits */
771 	retbits &= ~PL080_CONTROL_DWIDTH_MASK;
772 	retbits &= ~PL080_CONTROL_SWIDTH_MASK;
773 	retbits &= ~PL080_CONTROL_TRANSFER_SIZE_MASK;
774 
775 	/* Then set the bits according to the parameters */
776 	switch (srcwidth) {
777 	case 1:
778 		retbits |= PL080_WIDTH_8BIT << PL080_CONTROL_SWIDTH_SHIFT;
779 		break;
780 	case 2:
781 		retbits |= PL080_WIDTH_16BIT << PL080_CONTROL_SWIDTH_SHIFT;
782 		break;
783 	case 4:
784 		retbits |= PL080_WIDTH_32BIT << PL080_CONTROL_SWIDTH_SHIFT;
785 		break;
786 	default:
787 		BUG();
788 		break;
789 	}
790 
791 	switch (dstwidth) {
792 	case 1:
793 		retbits |= PL080_WIDTH_8BIT << PL080_CONTROL_DWIDTH_SHIFT;
794 		break;
795 	case 2:
796 		retbits |= PL080_WIDTH_16BIT << PL080_CONTROL_DWIDTH_SHIFT;
797 		break;
798 	case 4:
799 		retbits |= PL080_WIDTH_32BIT << PL080_CONTROL_DWIDTH_SHIFT;
800 		break;
801 	default:
802 		BUG();
803 		break;
804 	}
805 
806 	tsize &= PL080_CONTROL_TRANSFER_SIZE_MASK;
807 	retbits |= tsize << PL080_CONTROL_TRANSFER_SIZE_SHIFT;
808 	return retbits;
809 }
810 
811 struct pl08x_lli_build_data {
812 	struct pl08x_txd *txd;
813 	struct pl08x_bus_data srcbus;
814 	struct pl08x_bus_data dstbus;
815 	size_t remainder;
816 	u32 lli_bus;
817 };
818 
819 /*
820  * Autoselect a master bus to use for the transfer. Slave will be the chosen as
821  * victim in case src & dest are not similarly aligned. i.e. If after aligning
822  * masters address with width requirements of transfer (by sending few byte by
823  * byte data), slave is still not aligned, then its width will be reduced to
824  * BYTE.
825  * - prefers the destination bus if both available
826  * - prefers bus with fixed address (i.e. peripheral)
827  */
828 static void pl08x_choose_master_bus(struct pl08x_lli_build_data *bd,
829 	struct pl08x_bus_data **mbus, struct pl08x_bus_data **sbus, u32 cctl)
830 {
831 	if (!(cctl & PL080_CONTROL_DST_INCR)) {
832 		*mbus = &bd->dstbus;
833 		*sbus = &bd->srcbus;
834 	} else if (!(cctl & PL080_CONTROL_SRC_INCR)) {
835 		*mbus = &bd->srcbus;
836 		*sbus = &bd->dstbus;
837 	} else {
838 		if (bd->dstbus.buswidth >= bd->srcbus.buswidth) {
839 			*mbus = &bd->dstbus;
840 			*sbus = &bd->srcbus;
841 		} else {
842 			*mbus = &bd->srcbus;
843 			*sbus = &bd->dstbus;
844 		}
845 	}
846 }
847 
848 /*
849  * Fills in one LLI for a certain transfer descriptor and advance the counter
850  */
851 static void pl08x_fill_lli_for_desc(struct pl08x_driver_data *pl08x,
852 				    struct pl08x_lli_build_data *bd,
853 				    int num_llis, int len, u32 cctl, u32 cctl2)
854 {
855 	u32 offset = num_llis * pl08x->lli_words;
856 	u32 *llis_va = bd->txd->llis_va + offset;
857 	dma_addr_t llis_bus = bd->txd->llis_bus;
858 
859 	BUG_ON(num_llis >= MAX_NUM_TSFR_LLIS);
860 
861 	/* Advance the offset to next LLI. */
862 	offset += pl08x->lli_words;
863 
864 	llis_va[PL080_LLI_SRC] = bd->srcbus.addr;
865 	llis_va[PL080_LLI_DST] = bd->dstbus.addr;
866 	llis_va[PL080_LLI_LLI] = (llis_bus + sizeof(u32) * offset);
867 	llis_va[PL080_LLI_LLI] |= bd->lli_bus;
868 	llis_va[PL080_LLI_CCTL] = cctl;
869 	if (pl08x->vd->pl080s)
870 		llis_va[PL080S_LLI_CCTL2] = cctl2;
871 
872 	if (cctl & PL080_CONTROL_SRC_INCR)
873 		bd->srcbus.addr += len;
874 	if (cctl & PL080_CONTROL_DST_INCR)
875 		bd->dstbus.addr += len;
876 
877 	BUG_ON(bd->remainder < len);
878 
879 	bd->remainder -= len;
880 }
881 
882 static inline void prep_byte_width_lli(struct pl08x_driver_data *pl08x,
883 			struct pl08x_lli_build_data *bd, u32 *cctl, u32 len,
884 			int num_llis, size_t *total_bytes)
885 {
886 	*cctl = pl08x_cctl_bits(*cctl, 1, 1, len);
887 	pl08x_fill_lli_for_desc(pl08x, bd, num_llis, len, *cctl, len);
888 	(*total_bytes) += len;
889 }
890 
891 #ifdef VERBOSE_DEBUG
892 static void pl08x_dump_lli(struct pl08x_driver_data *pl08x,
893 			   const u32 *llis_va, int num_llis)
894 {
895 	int i;
896 
897 	if (pl08x->vd->pl080s) {
898 		dev_vdbg(&pl08x->adev->dev,
899 			"%-3s %-9s  %-10s %-10s %-10s %-10s %s\n",
900 			"lli", "", "csrc", "cdst", "clli", "cctl", "cctl2");
901 		for (i = 0; i < num_llis; i++) {
902 			dev_vdbg(&pl08x->adev->dev,
903 				"%3d @%p: 0x%08x 0x%08x 0x%08x 0x%08x 0x%08x\n",
904 				i, llis_va, llis_va[PL080_LLI_SRC],
905 				llis_va[PL080_LLI_DST], llis_va[PL080_LLI_LLI],
906 				llis_va[PL080_LLI_CCTL],
907 				llis_va[PL080S_LLI_CCTL2]);
908 			llis_va += pl08x->lli_words;
909 		}
910 	} else {
911 		dev_vdbg(&pl08x->adev->dev,
912 			"%-3s %-9s  %-10s %-10s %-10s %s\n",
913 			"lli", "", "csrc", "cdst", "clli", "cctl");
914 		for (i = 0; i < num_llis; i++) {
915 			dev_vdbg(&pl08x->adev->dev,
916 				"%3d @%p: 0x%08x 0x%08x 0x%08x 0x%08x\n",
917 				i, llis_va, llis_va[PL080_LLI_SRC],
918 				llis_va[PL080_LLI_DST], llis_va[PL080_LLI_LLI],
919 				llis_va[PL080_LLI_CCTL]);
920 			llis_va += pl08x->lli_words;
921 		}
922 	}
923 }
924 #else
925 static inline void pl08x_dump_lli(struct pl08x_driver_data *pl08x,
926 				  const u32 *llis_va, int num_llis) {}
927 #endif
928 
929 /*
930  * This fills in the table of LLIs for the transfer descriptor
931  * Note that we assume we never have to change the burst sizes
932  * Return 0 for error
933  */
934 static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
935 			      struct pl08x_txd *txd)
936 {
937 	struct pl08x_bus_data *mbus, *sbus;
938 	struct pl08x_lli_build_data bd;
939 	int num_llis = 0;
940 	u32 cctl, early_bytes = 0;
941 	size_t max_bytes_per_lli, total_bytes;
942 	u32 *llis_va, *last_lli;
943 	struct pl08x_sg *dsg;
944 
945 	txd->llis_va = dma_pool_alloc(pl08x->pool, GFP_NOWAIT, &txd->llis_bus);
946 	if (!txd->llis_va) {
947 		dev_err(&pl08x->adev->dev, "%s no memory for llis\n", __func__);
948 		return 0;
949 	}
950 
951 	bd.txd = txd;
952 	bd.lli_bus = (pl08x->lli_buses & PL08X_AHB2) ? PL080_LLI_LM_AHB2 : 0;
953 	cctl = txd->cctl;
954 
955 	/* Find maximum width of the source bus */
956 	bd.srcbus.maxwidth =
957 		pl08x_get_bytes_for_cctl((cctl & PL080_CONTROL_SWIDTH_MASK) >>
958 				       PL080_CONTROL_SWIDTH_SHIFT);
959 
960 	/* Find maximum width of the destination bus */
961 	bd.dstbus.maxwidth =
962 		pl08x_get_bytes_for_cctl((cctl & PL080_CONTROL_DWIDTH_MASK) >>
963 				       PL080_CONTROL_DWIDTH_SHIFT);
964 
965 	list_for_each_entry(dsg, &txd->dsg_list, node) {
966 		total_bytes = 0;
967 		cctl = txd->cctl;
968 
969 		bd.srcbus.addr = dsg->src_addr;
970 		bd.dstbus.addr = dsg->dst_addr;
971 		bd.remainder = dsg->len;
972 		bd.srcbus.buswidth = bd.srcbus.maxwidth;
973 		bd.dstbus.buswidth = bd.dstbus.maxwidth;
974 
975 		pl08x_choose_master_bus(&bd, &mbus, &sbus, cctl);
976 
977 		dev_vdbg(&pl08x->adev->dev,
978 			"src=0x%08llx%s/%u dst=0x%08llx%s/%u len=%zu\n",
979 			(u64)bd.srcbus.addr,
980 			cctl & PL080_CONTROL_SRC_INCR ? "+" : "",
981 			bd.srcbus.buswidth,
982 			(u64)bd.dstbus.addr,
983 			cctl & PL080_CONTROL_DST_INCR ? "+" : "",
984 			bd.dstbus.buswidth,
985 			bd.remainder);
986 		dev_vdbg(&pl08x->adev->dev, "mbus=%s sbus=%s\n",
987 			mbus == &bd.srcbus ? "src" : "dst",
988 			sbus == &bd.srcbus ? "src" : "dst");
989 
990 		/*
991 		 * Zero length is only allowed if all these requirements are
992 		 * met:
993 		 * - flow controller is peripheral.
994 		 * - src.addr is aligned to src.width
995 		 * - dst.addr is aligned to dst.width
996 		 *
997 		 * sg_len == 1 should be true, as there can be two cases here:
998 		 *
999 		 * - Memory addresses are contiguous and are not scattered.
1000 		 *   Here, Only one sg will be passed by user driver, with
1001 		 *   memory address and zero length. We pass this to controller
1002 		 *   and after the transfer it will receive the last burst
1003 		 *   request from peripheral and so transfer finishes.
1004 		 *
1005 		 * - Memory addresses are scattered and are not contiguous.
1006 		 *   Here, Obviously as DMA controller doesn't know when a lli's
1007 		 *   transfer gets over, it can't load next lli. So in this
1008 		 *   case, there has to be an assumption that only one lli is
1009 		 *   supported. Thus, we can't have scattered addresses.
1010 		 */
1011 		if (!bd.remainder) {
1012 			u32 fc = (txd->ccfg & PL080_CONFIG_FLOW_CONTROL_MASK) >>
1013 				PL080_CONFIG_FLOW_CONTROL_SHIFT;
1014 			if (!((fc >= PL080_FLOW_SRC2DST_DST) &&
1015 					(fc <= PL080_FLOW_SRC2DST_SRC))) {
1016 				dev_err(&pl08x->adev->dev, "%s sg len can't be zero",
1017 					__func__);
1018 				return 0;
1019 			}
1020 
1021 			if (!IS_BUS_ALIGNED(&bd.srcbus) ||
1022 				!IS_BUS_ALIGNED(&bd.dstbus)) {
1023 				dev_err(&pl08x->adev->dev,
1024 					"%s src & dst address must be aligned to src"
1025 					" & dst width if peripheral is flow controller",
1026 					__func__);
1027 				return 0;
1028 			}
1029 
1030 			cctl = pl08x_cctl_bits(cctl, bd.srcbus.buswidth,
1031 					bd.dstbus.buswidth, 0);
1032 			pl08x_fill_lli_for_desc(pl08x, &bd, num_llis++,
1033 					0, cctl, 0);
1034 			break;
1035 		}
1036 
1037 		/*
1038 		 * Send byte by byte for following cases
1039 		 * - Less than a bus width available
1040 		 * - until master bus is aligned
1041 		 */
1042 		if (bd.remainder < mbus->buswidth)
1043 			early_bytes = bd.remainder;
1044 		else if (!IS_BUS_ALIGNED(mbus)) {
1045 			early_bytes = mbus->buswidth -
1046 				(mbus->addr & (mbus->buswidth - 1));
1047 			if ((bd.remainder - early_bytes) < mbus->buswidth)
1048 				early_bytes = bd.remainder;
1049 		}
1050 
1051 		if (early_bytes) {
1052 			dev_vdbg(&pl08x->adev->dev,
1053 				"%s byte width LLIs (remain 0x%08zx)\n",
1054 				__func__, bd.remainder);
1055 			prep_byte_width_lli(pl08x, &bd, &cctl, early_bytes,
1056 				num_llis++, &total_bytes);
1057 		}
1058 
1059 		if (bd.remainder) {
1060 			/*
1061 			 * Master now aligned
1062 			 * - if slave is not then we must set its width down
1063 			 */
1064 			if (!IS_BUS_ALIGNED(sbus)) {
1065 				dev_dbg(&pl08x->adev->dev,
1066 					"%s set down bus width to one byte\n",
1067 					__func__);
1068 
1069 				sbus->buswidth = 1;
1070 			}
1071 
1072 			/*
1073 			 * Bytes transferred = tsize * src width, not
1074 			 * MIN(buswidths)
1075 			 */
1076 			max_bytes_per_lli = bd.srcbus.buswidth *
1077 						pl08x->vd->max_transfer_size;
1078 			dev_vdbg(&pl08x->adev->dev,
1079 				"%s max bytes per lli = %zu\n",
1080 				__func__, max_bytes_per_lli);
1081 
1082 			/*
1083 			 * Make largest possible LLIs until less than one bus
1084 			 * width left
1085 			 */
1086 			while (bd.remainder > (mbus->buswidth - 1)) {
1087 				size_t lli_len, tsize, width;
1088 
1089 				/*
1090 				 * If enough left try to send max possible,
1091 				 * otherwise try to send the remainder
1092 				 */
1093 				lli_len = min(bd.remainder, max_bytes_per_lli);
1094 
1095 				/*
1096 				 * Check against maximum bus alignment:
1097 				 * Calculate actual transfer size in relation to
1098 				 * bus width an get a maximum remainder of the
1099 				 * highest bus width - 1
1100 				 */
1101 				width = max(mbus->buswidth, sbus->buswidth);
1102 				lli_len = (lli_len / width) * width;
1103 				tsize = lli_len / bd.srcbus.buswidth;
1104 
1105 				dev_vdbg(&pl08x->adev->dev,
1106 					"%s fill lli with single lli chunk of "
1107 					"size 0x%08zx (remainder 0x%08zx)\n",
1108 					__func__, lli_len, bd.remainder);
1109 
1110 				cctl = pl08x_cctl_bits(cctl, bd.srcbus.buswidth,
1111 					bd.dstbus.buswidth, tsize);
1112 				pl08x_fill_lli_for_desc(pl08x, &bd, num_llis++,
1113 						lli_len, cctl, tsize);
1114 				total_bytes += lli_len;
1115 			}
1116 
1117 			/*
1118 			 * Send any odd bytes
1119 			 */
1120 			if (bd.remainder) {
1121 				dev_vdbg(&pl08x->adev->dev,
1122 					"%s align with boundary, send odd bytes (remain %zu)\n",
1123 					__func__, bd.remainder);
1124 				prep_byte_width_lli(pl08x, &bd, &cctl,
1125 					bd.remainder, num_llis++, &total_bytes);
1126 			}
1127 		}
1128 
1129 		if (total_bytes != dsg->len) {
1130 			dev_err(&pl08x->adev->dev,
1131 				"%s size of encoded lli:s don't match total txd, transferred 0x%08zx from size 0x%08zx\n",
1132 				__func__, total_bytes, dsg->len);
1133 			return 0;
1134 		}
1135 
1136 		if (num_llis >= MAX_NUM_TSFR_LLIS) {
1137 			dev_err(&pl08x->adev->dev,
1138 				"%s need to increase MAX_NUM_TSFR_LLIS from 0x%08x\n",
1139 				__func__, MAX_NUM_TSFR_LLIS);
1140 			return 0;
1141 		}
1142 	}
1143 
1144 	llis_va = txd->llis_va;
1145 	last_lli = llis_va + (num_llis - 1) * pl08x->lli_words;
1146 
1147 	if (txd->cyclic) {
1148 		/* Link back to the first LLI. */
1149 		last_lli[PL080_LLI_LLI] = txd->llis_bus | bd.lli_bus;
1150 	} else {
1151 		/* The final LLI terminates the LLI. */
1152 		last_lli[PL080_LLI_LLI] = 0;
1153 		/* The final LLI element shall also fire an interrupt. */
1154 		last_lli[PL080_LLI_CCTL] |= PL080_CONTROL_TC_IRQ_EN;
1155 	}
1156 
1157 	pl08x_dump_lli(pl08x, llis_va, num_llis);
1158 
1159 	return num_llis;
1160 }
1161 
1162 static void pl08x_free_txd(struct pl08x_driver_data *pl08x,
1163 			   struct pl08x_txd *txd)
1164 {
1165 	struct pl08x_sg *dsg, *_dsg;
1166 
1167 	if (txd->llis_va)
1168 		dma_pool_free(pl08x->pool, txd->llis_va, txd->llis_bus);
1169 
1170 	list_for_each_entry_safe(dsg, _dsg, &txd->dsg_list, node) {
1171 		list_del(&dsg->node);
1172 		kfree(dsg);
1173 	}
1174 
1175 	kfree(txd);
1176 }
1177 
1178 static void pl08x_desc_free(struct virt_dma_desc *vd)
1179 {
1180 	struct pl08x_txd *txd = to_pl08x_txd(&vd->tx);
1181 	struct pl08x_dma_chan *plchan = to_pl08x_chan(vd->tx.chan);
1182 
1183 	dma_descriptor_unmap(&vd->tx);
1184 	if (!txd->done)
1185 		pl08x_release_mux(plchan);
1186 
1187 	pl08x_free_txd(plchan->host, txd);
1188 }
1189 
1190 static void pl08x_free_txd_list(struct pl08x_driver_data *pl08x,
1191 				struct pl08x_dma_chan *plchan)
1192 {
1193 	LIST_HEAD(head);
1194 
1195 	vchan_get_all_descriptors(&plchan->vc, &head);
1196 	vchan_dma_desc_free_list(&plchan->vc, &head);
1197 }
1198 
1199 /*
1200  * The DMA ENGINE API
1201  */
1202 static void pl08x_free_chan_resources(struct dma_chan *chan)
1203 {
1204 	/* Ensure all queued descriptors are freed */
1205 	vchan_free_chan_resources(to_virt_chan(chan));
1206 }
1207 
1208 static struct dma_async_tx_descriptor *pl08x_prep_dma_interrupt(
1209 		struct dma_chan *chan, unsigned long flags)
1210 {
1211 	struct dma_async_tx_descriptor *retval = NULL;
1212 
1213 	return retval;
1214 }
1215 
1216 /*
1217  * Code accessing dma_async_is_complete() in a tight loop may give problems.
1218  * If slaves are relying on interrupts to signal completion this function
1219  * must not be called with interrupts disabled.
1220  */
1221 static enum dma_status pl08x_dma_tx_status(struct dma_chan *chan,
1222 		dma_cookie_t cookie, struct dma_tx_state *txstate)
1223 {
1224 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1225 	struct virt_dma_desc *vd;
1226 	unsigned long flags;
1227 	enum dma_status ret;
1228 	size_t bytes = 0;
1229 
1230 	ret = dma_cookie_status(chan, cookie, txstate);
1231 	if (ret == DMA_COMPLETE)
1232 		return ret;
1233 
1234 	/*
1235 	 * There's no point calculating the residue if there's
1236 	 * no txstate to store the value.
1237 	 */
1238 	if (!txstate) {
1239 		if (plchan->state == PL08X_CHAN_PAUSED)
1240 			ret = DMA_PAUSED;
1241 		return ret;
1242 	}
1243 
1244 	spin_lock_irqsave(&plchan->vc.lock, flags);
1245 	ret = dma_cookie_status(chan, cookie, txstate);
1246 	if (ret != DMA_COMPLETE) {
1247 		vd = vchan_find_desc(&plchan->vc, cookie);
1248 		if (vd) {
1249 			/* On the issued list, so hasn't been processed yet */
1250 			struct pl08x_txd *txd = to_pl08x_txd(&vd->tx);
1251 			struct pl08x_sg *dsg;
1252 
1253 			list_for_each_entry(dsg, &txd->dsg_list, node)
1254 				bytes += dsg->len;
1255 		} else {
1256 			bytes = pl08x_getbytes_chan(plchan);
1257 		}
1258 	}
1259 	spin_unlock_irqrestore(&plchan->vc.lock, flags);
1260 
1261 	/*
1262 	 * This cookie not complete yet
1263 	 * Get number of bytes left in the active transactions and queue
1264 	 */
1265 	dma_set_residue(txstate, bytes);
1266 
1267 	if (plchan->state == PL08X_CHAN_PAUSED && ret == DMA_IN_PROGRESS)
1268 		ret = DMA_PAUSED;
1269 
1270 	/* Whether waiting or running, we're in progress */
1271 	return ret;
1272 }
1273 
1274 /* PrimeCell DMA extension */
1275 struct burst_table {
1276 	u32 burstwords;
1277 	u32 reg;
1278 };
1279 
1280 static const struct burst_table burst_sizes[] = {
1281 	{
1282 		.burstwords = 256,
1283 		.reg = PL080_BSIZE_256,
1284 	},
1285 	{
1286 		.burstwords = 128,
1287 		.reg = PL080_BSIZE_128,
1288 	},
1289 	{
1290 		.burstwords = 64,
1291 		.reg = PL080_BSIZE_64,
1292 	},
1293 	{
1294 		.burstwords = 32,
1295 		.reg = PL080_BSIZE_32,
1296 	},
1297 	{
1298 		.burstwords = 16,
1299 		.reg = PL080_BSIZE_16,
1300 	},
1301 	{
1302 		.burstwords = 8,
1303 		.reg = PL080_BSIZE_8,
1304 	},
1305 	{
1306 		.burstwords = 4,
1307 		.reg = PL080_BSIZE_4,
1308 	},
1309 	{
1310 		.burstwords = 0,
1311 		.reg = PL080_BSIZE_1,
1312 	},
1313 };
1314 
1315 /*
1316  * Given the source and destination available bus masks, select which
1317  * will be routed to each port.  We try to have source and destination
1318  * on separate ports, but always respect the allowable settings.
1319  */
1320 static u32 pl08x_select_bus(u8 src, u8 dst)
1321 {
1322 	u32 cctl = 0;
1323 
1324 	if (!(dst & PL08X_AHB1) || ((dst & PL08X_AHB2) && (src & PL08X_AHB1)))
1325 		cctl |= PL080_CONTROL_DST_AHB2;
1326 	if (!(src & PL08X_AHB1) || ((src & PL08X_AHB2) && !(dst & PL08X_AHB2)))
1327 		cctl |= PL080_CONTROL_SRC_AHB2;
1328 
1329 	return cctl;
1330 }
1331 
1332 static u32 pl08x_cctl(u32 cctl)
1333 {
1334 	cctl &= ~(PL080_CONTROL_SRC_AHB2 | PL080_CONTROL_DST_AHB2 |
1335 		  PL080_CONTROL_SRC_INCR | PL080_CONTROL_DST_INCR |
1336 		  PL080_CONTROL_PROT_MASK);
1337 
1338 	/* Access the cell in privileged mode, non-bufferable, non-cacheable */
1339 	return cctl | PL080_CONTROL_PROT_SYS;
1340 }
1341 
1342 static u32 pl08x_width(enum dma_slave_buswidth width)
1343 {
1344 	switch (width) {
1345 	case DMA_SLAVE_BUSWIDTH_1_BYTE:
1346 		return PL080_WIDTH_8BIT;
1347 	case DMA_SLAVE_BUSWIDTH_2_BYTES:
1348 		return PL080_WIDTH_16BIT;
1349 	case DMA_SLAVE_BUSWIDTH_4_BYTES:
1350 		return PL080_WIDTH_32BIT;
1351 	default:
1352 		return ~0;
1353 	}
1354 }
1355 
1356 static u32 pl08x_burst(u32 maxburst)
1357 {
1358 	int i;
1359 
1360 	for (i = 0; i < ARRAY_SIZE(burst_sizes); i++)
1361 		if (burst_sizes[i].burstwords <= maxburst)
1362 			break;
1363 
1364 	return burst_sizes[i].reg;
1365 }
1366 
1367 static u32 pl08x_get_cctl(struct pl08x_dma_chan *plchan,
1368 	enum dma_slave_buswidth addr_width, u32 maxburst)
1369 {
1370 	u32 width, burst, cctl = 0;
1371 
1372 	width = pl08x_width(addr_width);
1373 	if (width == ~0)
1374 		return ~0;
1375 
1376 	cctl |= width << PL080_CONTROL_SWIDTH_SHIFT;
1377 	cctl |= width << PL080_CONTROL_DWIDTH_SHIFT;
1378 
1379 	/*
1380 	 * If this channel will only request single transfers, set this
1381 	 * down to ONE element.  Also select one element if no maxburst
1382 	 * is specified.
1383 	 */
1384 	if (plchan->cd->single)
1385 		maxburst = 1;
1386 
1387 	burst = pl08x_burst(maxburst);
1388 	cctl |= burst << PL080_CONTROL_SB_SIZE_SHIFT;
1389 	cctl |= burst << PL080_CONTROL_DB_SIZE_SHIFT;
1390 
1391 	return pl08x_cctl(cctl);
1392 }
1393 
1394 /*
1395  * Slave transactions callback to the slave device to allow
1396  * synchronization of slave DMA signals with the DMAC enable
1397  */
1398 static void pl08x_issue_pending(struct dma_chan *chan)
1399 {
1400 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1401 	unsigned long flags;
1402 
1403 	spin_lock_irqsave(&plchan->vc.lock, flags);
1404 	if (vchan_issue_pending(&plchan->vc)) {
1405 		if (!plchan->phychan && plchan->state != PL08X_CHAN_WAITING)
1406 			pl08x_phy_alloc_and_start(plchan);
1407 	}
1408 	spin_unlock_irqrestore(&plchan->vc.lock, flags);
1409 }
1410 
1411 static struct pl08x_txd *pl08x_get_txd(struct pl08x_dma_chan *plchan)
1412 {
1413 	struct pl08x_txd *txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
1414 
1415 	if (txd) {
1416 		INIT_LIST_HEAD(&txd->dsg_list);
1417 
1418 		/* Always enable error and terminal interrupts */
1419 		txd->ccfg = PL080_CONFIG_ERR_IRQ_MASK |
1420 			    PL080_CONFIG_TC_IRQ_MASK;
1421 	}
1422 	return txd;
1423 }
1424 
1425 /*
1426  * Initialize a descriptor to be used by memcpy submit
1427  */
1428 static struct dma_async_tx_descriptor *pl08x_prep_dma_memcpy(
1429 		struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
1430 		size_t len, unsigned long flags)
1431 {
1432 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1433 	struct pl08x_driver_data *pl08x = plchan->host;
1434 	struct pl08x_txd *txd;
1435 	struct pl08x_sg *dsg;
1436 	int ret;
1437 
1438 	txd = pl08x_get_txd(plchan);
1439 	if (!txd) {
1440 		dev_err(&pl08x->adev->dev,
1441 			"%s no memory for descriptor\n", __func__);
1442 		return NULL;
1443 	}
1444 
1445 	dsg = kzalloc(sizeof(struct pl08x_sg), GFP_NOWAIT);
1446 	if (!dsg) {
1447 		pl08x_free_txd(pl08x, txd);
1448 		return NULL;
1449 	}
1450 	list_add_tail(&dsg->node, &txd->dsg_list);
1451 
1452 	dsg->src_addr = src;
1453 	dsg->dst_addr = dest;
1454 	dsg->len = len;
1455 
1456 	/* Set platform data for m2m */
1457 	txd->ccfg |= PL080_FLOW_MEM2MEM << PL080_CONFIG_FLOW_CONTROL_SHIFT;
1458 	txd->cctl = pl08x->pd->memcpy_channel.cctl_memcpy &
1459 			~(PL080_CONTROL_DST_AHB2 | PL080_CONTROL_SRC_AHB2);
1460 
1461 	/* Both to be incremented or the code will break */
1462 	txd->cctl |= PL080_CONTROL_SRC_INCR | PL080_CONTROL_DST_INCR;
1463 
1464 	if (pl08x->vd->dualmaster)
1465 		txd->cctl |= pl08x_select_bus(pl08x->mem_buses,
1466 					      pl08x->mem_buses);
1467 
1468 	ret = pl08x_fill_llis_for_desc(plchan->host, txd);
1469 	if (!ret) {
1470 		pl08x_free_txd(pl08x, txd);
1471 		return NULL;
1472 	}
1473 
1474 	return vchan_tx_prep(&plchan->vc, &txd->vd, flags);
1475 }
1476 
1477 static struct pl08x_txd *pl08x_init_txd(
1478 		struct dma_chan *chan,
1479 		enum dma_transfer_direction direction,
1480 		dma_addr_t *slave_addr)
1481 {
1482 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1483 	struct pl08x_driver_data *pl08x = plchan->host;
1484 	struct pl08x_txd *txd;
1485 	enum dma_slave_buswidth addr_width;
1486 	int ret, tmp;
1487 	u8 src_buses, dst_buses;
1488 	u32 maxburst, cctl;
1489 
1490 	txd = pl08x_get_txd(plchan);
1491 	if (!txd) {
1492 		dev_err(&pl08x->adev->dev, "%s no txd\n", __func__);
1493 		return NULL;
1494 	}
1495 
1496 	/*
1497 	 * Set up addresses, the PrimeCell configured address
1498 	 * will take precedence since this may configure the
1499 	 * channel target address dynamically at runtime.
1500 	 */
1501 	if (direction == DMA_MEM_TO_DEV) {
1502 		cctl = PL080_CONTROL_SRC_INCR;
1503 		*slave_addr = plchan->cfg.dst_addr;
1504 		addr_width = plchan->cfg.dst_addr_width;
1505 		maxburst = plchan->cfg.dst_maxburst;
1506 		src_buses = pl08x->mem_buses;
1507 		dst_buses = plchan->cd->periph_buses;
1508 	} else if (direction == DMA_DEV_TO_MEM) {
1509 		cctl = PL080_CONTROL_DST_INCR;
1510 		*slave_addr = plchan->cfg.src_addr;
1511 		addr_width = plchan->cfg.src_addr_width;
1512 		maxburst = plchan->cfg.src_maxburst;
1513 		src_buses = plchan->cd->periph_buses;
1514 		dst_buses = pl08x->mem_buses;
1515 	} else {
1516 		pl08x_free_txd(pl08x, txd);
1517 		dev_err(&pl08x->adev->dev,
1518 			"%s direction unsupported\n", __func__);
1519 		return NULL;
1520 	}
1521 
1522 	cctl |= pl08x_get_cctl(plchan, addr_width, maxburst);
1523 	if (cctl == ~0) {
1524 		pl08x_free_txd(pl08x, txd);
1525 		dev_err(&pl08x->adev->dev,
1526 			"DMA slave configuration botched?\n");
1527 		return NULL;
1528 	}
1529 
1530 	txd->cctl = cctl | pl08x_select_bus(src_buses, dst_buses);
1531 
1532 	if (plchan->cfg.device_fc)
1533 		tmp = (direction == DMA_MEM_TO_DEV) ? PL080_FLOW_MEM2PER_PER :
1534 			PL080_FLOW_PER2MEM_PER;
1535 	else
1536 		tmp = (direction == DMA_MEM_TO_DEV) ? PL080_FLOW_MEM2PER :
1537 			PL080_FLOW_PER2MEM;
1538 
1539 	txd->ccfg |= tmp << PL080_CONFIG_FLOW_CONTROL_SHIFT;
1540 
1541 	ret = pl08x_request_mux(plchan);
1542 	if (ret < 0) {
1543 		pl08x_free_txd(pl08x, txd);
1544 		dev_dbg(&pl08x->adev->dev,
1545 			"unable to mux for transfer on %s due to platform restrictions\n",
1546 			plchan->name);
1547 		return NULL;
1548 	}
1549 
1550 	dev_dbg(&pl08x->adev->dev, "allocated DMA request signal %d for xfer on %s\n",
1551 		 plchan->signal, plchan->name);
1552 
1553 	/* Assign the flow control signal to this channel */
1554 	if (direction == DMA_MEM_TO_DEV)
1555 		txd->ccfg |= plchan->signal << PL080_CONFIG_DST_SEL_SHIFT;
1556 	else
1557 		txd->ccfg |= plchan->signal << PL080_CONFIG_SRC_SEL_SHIFT;
1558 
1559 	return txd;
1560 }
1561 
1562 static int pl08x_tx_add_sg(struct pl08x_txd *txd,
1563 			   enum dma_transfer_direction direction,
1564 			   dma_addr_t slave_addr,
1565 			   dma_addr_t buf_addr,
1566 			   unsigned int len)
1567 {
1568 	struct pl08x_sg *dsg;
1569 
1570 	dsg = kzalloc(sizeof(struct pl08x_sg), GFP_NOWAIT);
1571 	if (!dsg)
1572 		return -ENOMEM;
1573 
1574 	list_add_tail(&dsg->node, &txd->dsg_list);
1575 
1576 	dsg->len = len;
1577 	if (direction == DMA_MEM_TO_DEV) {
1578 		dsg->src_addr = buf_addr;
1579 		dsg->dst_addr = slave_addr;
1580 	} else {
1581 		dsg->src_addr = slave_addr;
1582 		dsg->dst_addr = buf_addr;
1583 	}
1584 
1585 	return 0;
1586 }
1587 
1588 static struct dma_async_tx_descriptor *pl08x_prep_slave_sg(
1589 		struct dma_chan *chan, struct scatterlist *sgl,
1590 		unsigned int sg_len, enum dma_transfer_direction direction,
1591 		unsigned long flags, void *context)
1592 {
1593 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1594 	struct pl08x_driver_data *pl08x = plchan->host;
1595 	struct pl08x_txd *txd;
1596 	struct scatterlist *sg;
1597 	int ret, tmp;
1598 	dma_addr_t slave_addr;
1599 
1600 	dev_dbg(&pl08x->adev->dev, "%s prepare transaction of %d bytes from %s\n",
1601 			__func__, sg_dma_len(sgl), plchan->name);
1602 
1603 	txd = pl08x_init_txd(chan, direction, &slave_addr);
1604 	if (!txd)
1605 		return NULL;
1606 
1607 	for_each_sg(sgl, sg, sg_len, tmp) {
1608 		ret = pl08x_tx_add_sg(txd, direction, slave_addr,
1609 				      sg_dma_address(sg),
1610 				      sg_dma_len(sg));
1611 		if (ret) {
1612 			pl08x_release_mux(plchan);
1613 			pl08x_free_txd(pl08x, txd);
1614 			dev_err(&pl08x->adev->dev, "%s no mem for pl080 sg\n",
1615 					__func__);
1616 			return NULL;
1617 		}
1618 	}
1619 
1620 	ret = pl08x_fill_llis_for_desc(plchan->host, txd);
1621 	if (!ret) {
1622 		pl08x_release_mux(plchan);
1623 		pl08x_free_txd(pl08x, txd);
1624 		return NULL;
1625 	}
1626 
1627 	return vchan_tx_prep(&plchan->vc, &txd->vd, flags);
1628 }
1629 
1630 static struct dma_async_tx_descriptor *pl08x_prep_dma_cyclic(
1631 		struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
1632 		size_t period_len, enum dma_transfer_direction direction,
1633 		unsigned long flags)
1634 {
1635 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1636 	struct pl08x_driver_data *pl08x = plchan->host;
1637 	struct pl08x_txd *txd;
1638 	int ret, tmp;
1639 	dma_addr_t slave_addr;
1640 
1641 	dev_dbg(&pl08x->adev->dev,
1642 		"%s prepare cyclic transaction of %zd/%zd bytes %s %s\n",
1643 		__func__, period_len, buf_len,
1644 		direction == DMA_MEM_TO_DEV ? "to" : "from",
1645 		plchan->name);
1646 
1647 	txd = pl08x_init_txd(chan, direction, &slave_addr);
1648 	if (!txd)
1649 		return NULL;
1650 
1651 	txd->cyclic = true;
1652 	txd->cctl |= PL080_CONTROL_TC_IRQ_EN;
1653 	for (tmp = 0; tmp < buf_len; tmp += period_len) {
1654 		ret = pl08x_tx_add_sg(txd, direction, slave_addr,
1655 				      buf_addr + tmp, period_len);
1656 		if (ret) {
1657 			pl08x_release_mux(plchan);
1658 			pl08x_free_txd(pl08x, txd);
1659 			return NULL;
1660 		}
1661 	}
1662 
1663 	ret = pl08x_fill_llis_for_desc(plchan->host, txd);
1664 	if (!ret) {
1665 		pl08x_release_mux(plchan);
1666 		pl08x_free_txd(pl08x, txd);
1667 		return NULL;
1668 	}
1669 
1670 	return vchan_tx_prep(&plchan->vc, &txd->vd, flags);
1671 }
1672 
1673 static int pl08x_config(struct dma_chan *chan,
1674 			struct dma_slave_config *config)
1675 {
1676 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1677 	struct pl08x_driver_data *pl08x = plchan->host;
1678 
1679 	if (!plchan->slave)
1680 		return -EINVAL;
1681 
1682 	/* Reject definitely invalid configurations */
1683 	if (config->src_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES ||
1684 	    config->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES)
1685 		return -EINVAL;
1686 
1687 	if (config->device_fc && pl08x->vd->pl080s) {
1688 		dev_err(&pl08x->adev->dev,
1689 			"%s: PL080S does not support peripheral flow control\n",
1690 			__func__);
1691 		return -EINVAL;
1692 	}
1693 
1694 	plchan->cfg = *config;
1695 
1696 	return 0;
1697 }
1698 
1699 static int pl08x_terminate_all(struct dma_chan *chan)
1700 {
1701 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1702 	struct pl08x_driver_data *pl08x = plchan->host;
1703 	unsigned long flags;
1704 
1705 	spin_lock_irqsave(&plchan->vc.lock, flags);
1706 	if (!plchan->phychan && !plchan->at) {
1707 		spin_unlock_irqrestore(&plchan->vc.lock, flags);
1708 		return 0;
1709 	}
1710 
1711 	plchan->state = PL08X_CHAN_IDLE;
1712 
1713 	if (plchan->phychan) {
1714 		/*
1715 		 * Mark physical channel as free and free any slave
1716 		 * signal
1717 		 */
1718 		pl08x_phy_free(plchan);
1719 	}
1720 	/* Dequeue jobs and free LLIs */
1721 	if (plchan->at) {
1722 		pl08x_desc_free(&plchan->at->vd);
1723 		plchan->at = NULL;
1724 	}
1725 	/* Dequeue jobs not yet fired as well */
1726 	pl08x_free_txd_list(pl08x, plchan);
1727 
1728 	spin_unlock_irqrestore(&plchan->vc.lock, flags);
1729 
1730 	return 0;
1731 }
1732 
1733 static int pl08x_pause(struct dma_chan *chan)
1734 {
1735 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1736 	unsigned long flags;
1737 
1738 	/*
1739 	 * Anything succeeds on channels with no physical allocation and
1740 	 * no queued transfers.
1741 	 */
1742 	spin_lock_irqsave(&plchan->vc.lock, flags);
1743 	if (!plchan->phychan && !plchan->at) {
1744 		spin_unlock_irqrestore(&plchan->vc.lock, flags);
1745 		return 0;
1746 	}
1747 
1748 	pl08x_pause_phy_chan(plchan->phychan);
1749 	plchan->state = PL08X_CHAN_PAUSED;
1750 
1751 	spin_unlock_irqrestore(&plchan->vc.lock, flags);
1752 
1753 	return 0;
1754 }
1755 
1756 static int pl08x_resume(struct dma_chan *chan)
1757 {
1758 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1759 	unsigned long flags;
1760 
1761 	/*
1762 	 * Anything succeeds on channels with no physical allocation and
1763 	 * no queued transfers.
1764 	 */
1765 	spin_lock_irqsave(&plchan->vc.lock, flags);
1766 	if (!plchan->phychan && !plchan->at) {
1767 		spin_unlock_irqrestore(&plchan->vc.lock, flags);
1768 		return 0;
1769 	}
1770 
1771 	pl08x_resume_phy_chan(plchan->phychan);
1772 	plchan->state = PL08X_CHAN_RUNNING;
1773 
1774 	spin_unlock_irqrestore(&plchan->vc.lock, flags);
1775 
1776 	return 0;
1777 }
1778 
1779 bool pl08x_filter_id(struct dma_chan *chan, void *chan_id)
1780 {
1781 	struct pl08x_dma_chan *plchan;
1782 	char *name = chan_id;
1783 
1784 	/* Reject channels for devices not bound to this driver */
1785 	if (chan->device->dev->driver != &pl08x_amba_driver.drv)
1786 		return false;
1787 
1788 	plchan = to_pl08x_chan(chan);
1789 
1790 	/* Check that the channel is not taken! */
1791 	if (!strcmp(plchan->name, name))
1792 		return true;
1793 
1794 	return false;
1795 }
1796 EXPORT_SYMBOL_GPL(pl08x_filter_id);
1797 
1798 static bool pl08x_filter_fn(struct dma_chan *chan, void *chan_id)
1799 {
1800 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
1801 
1802 	return plchan->cd == chan_id;
1803 }
1804 
1805 /*
1806  * Just check that the device is there and active
1807  * TODO: turn this bit on/off depending on the number of physical channels
1808  * actually used, if it is zero... well shut it off. That will save some
1809  * power. Cut the clock at the same time.
1810  */
1811 static void pl08x_ensure_on(struct pl08x_driver_data *pl08x)
1812 {
1813 	/* The Nomadik variant does not have the config register */
1814 	if (pl08x->vd->nomadik)
1815 		return;
1816 	writel(PL080_CONFIG_ENABLE, pl08x->base + PL080_CONFIG);
1817 }
1818 
1819 static irqreturn_t pl08x_irq(int irq, void *dev)
1820 {
1821 	struct pl08x_driver_data *pl08x = dev;
1822 	u32 mask = 0, err, tc, i;
1823 
1824 	/* check & clear - ERR & TC interrupts */
1825 	err = readl(pl08x->base + PL080_ERR_STATUS);
1826 	if (err) {
1827 		dev_err(&pl08x->adev->dev, "%s error interrupt, register value 0x%08x\n",
1828 			__func__, err);
1829 		writel(err, pl08x->base + PL080_ERR_CLEAR);
1830 	}
1831 	tc = readl(pl08x->base + PL080_TC_STATUS);
1832 	if (tc)
1833 		writel(tc, pl08x->base + PL080_TC_CLEAR);
1834 
1835 	if (!err && !tc)
1836 		return IRQ_NONE;
1837 
1838 	for (i = 0; i < pl08x->vd->channels; i++) {
1839 		if ((BIT(i) & err) || (BIT(i) & tc)) {
1840 			/* Locate physical channel */
1841 			struct pl08x_phy_chan *phychan = &pl08x->phy_chans[i];
1842 			struct pl08x_dma_chan *plchan = phychan->serving;
1843 			struct pl08x_txd *tx;
1844 
1845 			if (!plchan) {
1846 				dev_err(&pl08x->adev->dev,
1847 					"%s Error TC interrupt on unused channel: 0x%08x\n",
1848 					__func__, i);
1849 				continue;
1850 			}
1851 
1852 			spin_lock(&plchan->vc.lock);
1853 			tx = plchan->at;
1854 			if (tx && tx->cyclic) {
1855 				vchan_cyclic_callback(&tx->vd);
1856 			} else if (tx) {
1857 				plchan->at = NULL;
1858 				/*
1859 				 * This descriptor is done, release its mux
1860 				 * reservation.
1861 				 */
1862 				pl08x_release_mux(plchan);
1863 				tx->done = true;
1864 				vchan_cookie_complete(&tx->vd);
1865 
1866 				/*
1867 				 * And start the next descriptor (if any),
1868 				 * otherwise free this channel.
1869 				 */
1870 				if (vchan_next_desc(&plchan->vc))
1871 					pl08x_start_next_txd(plchan);
1872 				else
1873 					pl08x_phy_free(plchan);
1874 			}
1875 			spin_unlock(&plchan->vc.lock);
1876 
1877 			mask |= BIT(i);
1878 		}
1879 	}
1880 
1881 	return mask ? IRQ_HANDLED : IRQ_NONE;
1882 }
1883 
1884 static void pl08x_dma_slave_init(struct pl08x_dma_chan *chan)
1885 {
1886 	chan->slave = true;
1887 	chan->name = chan->cd->bus_id;
1888 	chan->cfg.src_addr = chan->cd->addr;
1889 	chan->cfg.dst_addr = chan->cd->addr;
1890 }
1891 
1892 /*
1893  * Initialise the DMAC memcpy/slave channels.
1894  * Make a local wrapper to hold required data
1895  */
1896 static int pl08x_dma_init_virtual_channels(struct pl08x_driver_data *pl08x,
1897 		struct dma_device *dmadev, unsigned int channels, bool slave)
1898 {
1899 	struct pl08x_dma_chan *chan;
1900 	int i;
1901 
1902 	INIT_LIST_HEAD(&dmadev->channels);
1903 
1904 	/*
1905 	 * Register as many many memcpy as we have physical channels,
1906 	 * we won't always be able to use all but the code will have
1907 	 * to cope with that situation.
1908 	 */
1909 	for (i = 0; i < channels; i++) {
1910 		chan = kzalloc(sizeof(*chan), GFP_KERNEL);
1911 		if (!chan)
1912 			return -ENOMEM;
1913 
1914 		chan->host = pl08x;
1915 		chan->state = PL08X_CHAN_IDLE;
1916 		chan->signal = -1;
1917 
1918 		if (slave) {
1919 			chan->cd = &pl08x->pd->slave_channels[i];
1920 			/*
1921 			 * Some implementations have muxed signals, whereas some
1922 			 * use a mux in front of the signals and need dynamic
1923 			 * assignment of signals.
1924 			 */
1925 			chan->signal = i;
1926 			pl08x_dma_slave_init(chan);
1927 		} else {
1928 			chan->cd = &pl08x->pd->memcpy_channel;
1929 			chan->name = kasprintf(GFP_KERNEL, "memcpy%d", i);
1930 			if (!chan->name) {
1931 				kfree(chan);
1932 				return -ENOMEM;
1933 			}
1934 		}
1935 		dev_dbg(&pl08x->adev->dev,
1936 			 "initialize virtual channel \"%s\"\n",
1937 			 chan->name);
1938 
1939 		chan->vc.desc_free = pl08x_desc_free;
1940 		vchan_init(&chan->vc, dmadev);
1941 	}
1942 	dev_info(&pl08x->adev->dev, "initialized %d virtual %s channels\n",
1943 		 i, slave ? "slave" : "memcpy");
1944 	return i;
1945 }
1946 
1947 static void pl08x_free_virtual_channels(struct dma_device *dmadev)
1948 {
1949 	struct pl08x_dma_chan *chan = NULL;
1950 	struct pl08x_dma_chan *next;
1951 
1952 	list_for_each_entry_safe(chan,
1953 				 next, &dmadev->channels, vc.chan.device_node) {
1954 		list_del(&chan->vc.chan.device_node);
1955 		kfree(chan);
1956 	}
1957 }
1958 
1959 #ifdef CONFIG_DEBUG_FS
1960 static const char *pl08x_state_str(enum pl08x_dma_chan_state state)
1961 {
1962 	switch (state) {
1963 	case PL08X_CHAN_IDLE:
1964 		return "idle";
1965 	case PL08X_CHAN_RUNNING:
1966 		return "running";
1967 	case PL08X_CHAN_PAUSED:
1968 		return "paused";
1969 	case PL08X_CHAN_WAITING:
1970 		return "waiting";
1971 	default:
1972 		break;
1973 	}
1974 	return "UNKNOWN STATE";
1975 }
1976 
1977 static int pl08x_debugfs_show(struct seq_file *s, void *data)
1978 {
1979 	struct pl08x_driver_data *pl08x = s->private;
1980 	struct pl08x_dma_chan *chan;
1981 	struct pl08x_phy_chan *ch;
1982 	unsigned long flags;
1983 	int i;
1984 
1985 	seq_printf(s, "PL08x physical channels:\n");
1986 	seq_printf(s, "CHANNEL:\tUSER:\n");
1987 	seq_printf(s, "--------\t-----\n");
1988 	for (i = 0; i < pl08x->vd->channels; i++) {
1989 		struct pl08x_dma_chan *virt_chan;
1990 
1991 		ch = &pl08x->phy_chans[i];
1992 
1993 		spin_lock_irqsave(&ch->lock, flags);
1994 		virt_chan = ch->serving;
1995 
1996 		seq_printf(s, "%d\t\t%s%s\n",
1997 			   ch->id,
1998 			   virt_chan ? virt_chan->name : "(none)",
1999 			   ch->locked ? " LOCKED" : "");
2000 
2001 		spin_unlock_irqrestore(&ch->lock, flags);
2002 	}
2003 
2004 	seq_printf(s, "\nPL08x virtual memcpy channels:\n");
2005 	seq_printf(s, "CHANNEL:\tSTATE:\n");
2006 	seq_printf(s, "--------\t------\n");
2007 	list_for_each_entry(chan, &pl08x->memcpy.channels, vc.chan.device_node) {
2008 		seq_printf(s, "%s\t\t%s\n", chan->name,
2009 			   pl08x_state_str(chan->state));
2010 	}
2011 
2012 	seq_printf(s, "\nPL08x virtual slave channels:\n");
2013 	seq_printf(s, "CHANNEL:\tSTATE:\n");
2014 	seq_printf(s, "--------\t------\n");
2015 	list_for_each_entry(chan, &pl08x->slave.channels, vc.chan.device_node) {
2016 		seq_printf(s, "%s\t\t%s\n", chan->name,
2017 			   pl08x_state_str(chan->state));
2018 	}
2019 
2020 	return 0;
2021 }
2022 
2023 static int pl08x_debugfs_open(struct inode *inode, struct file *file)
2024 {
2025 	return single_open(file, pl08x_debugfs_show, inode->i_private);
2026 }
2027 
2028 static const struct file_operations pl08x_debugfs_operations = {
2029 	.open		= pl08x_debugfs_open,
2030 	.read		= seq_read,
2031 	.llseek		= seq_lseek,
2032 	.release	= single_release,
2033 };
2034 
2035 static void init_pl08x_debugfs(struct pl08x_driver_data *pl08x)
2036 {
2037 	/* Expose a simple debugfs interface to view all clocks */
2038 	(void) debugfs_create_file(dev_name(&pl08x->adev->dev),
2039 			S_IFREG | S_IRUGO, NULL, pl08x,
2040 			&pl08x_debugfs_operations);
2041 }
2042 
2043 #else
2044 static inline void init_pl08x_debugfs(struct pl08x_driver_data *pl08x)
2045 {
2046 }
2047 #endif
2048 
2049 #ifdef CONFIG_OF
2050 static struct dma_chan *pl08x_find_chan_id(struct pl08x_driver_data *pl08x,
2051 					 u32 id)
2052 {
2053 	struct pl08x_dma_chan *chan;
2054 
2055 	list_for_each_entry(chan, &pl08x->slave.channels, vc.chan.device_node) {
2056 		if (chan->signal == id)
2057 			return &chan->vc.chan;
2058 	}
2059 
2060 	return NULL;
2061 }
2062 
2063 static struct dma_chan *pl08x_of_xlate(struct of_phandle_args *dma_spec,
2064 				       struct of_dma *ofdma)
2065 {
2066 	struct pl08x_driver_data *pl08x = ofdma->of_dma_data;
2067 	struct dma_chan *dma_chan;
2068 	struct pl08x_dma_chan *plchan;
2069 
2070 	if (!pl08x)
2071 		return NULL;
2072 
2073 	if (dma_spec->args_count != 2) {
2074 		dev_err(&pl08x->adev->dev,
2075 			"DMA channel translation requires two cells\n");
2076 		return NULL;
2077 	}
2078 
2079 	dma_chan = pl08x_find_chan_id(pl08x, dma_spec->args[0]);
2080 	if (!dma_chan) {
2081 		dev_err(&pl08x->adev->dev,
2082 			"DMA slave channel not found\n");
2083 		return NULL;
2084 	}
2085 
2086 	plchan = to_pl08x_chan(dma_chan);
2087 	dev_dbg(&pl08x->adev->dev,
2088 		"translated channel for signal %d\n",
2089 		dma_spec->args[0]);
2090 
2091 	/* Augment channel data for applicable AHB buses */
2092 	plchan->cd->periph_buses = dma_spec->args[1];
2093 	return dma_get_slave_channel(dma_chan);
2094 }
2095 
2096 static int pl08x_of_probe(struct amba_device *adev,
2097 			  struct pl08x_driver_data *pl08x,
2098 			  struct device_node *np)
2099 {
2100 	struct pl08x_platform_data *pd;
2101 	struct pl08x_channel_data *chanp = NULL;
2102 	u32 cctl_memcpy = 0;
2103 	u32 val;
2104 	int ret;
2105 	int i;
2106 
2107 	pd = devm_kzalloc(&adev->dev, sizeof(*pd), GFP_KERNEL);
2108 	if (!pd)
2109 		return -ENOMEM;
2110 
2111 	/* Eligible bus masters for fetching LLIs */
2112 	if (of_property_read_bool(np, "lli-bus-interface-ahb1"))
2113 		pd->lli_buses |= PL08X_AHB1;
2114 	if (of_property_read_bool(np, "lli-bus-interface-ahb2"))
2115 		pd->lli_buses |= PL08X_AHB2;
2116 	if (!pd->lli_buses) {
2117 		dev_info(&adev->dev, "no bus masters for LLIs stated, assume all\n");
2118 		pd->lli_buses |= PL08X_AHB1 | PL08X_AHB2;
2119 	}
2120 
2121 	/* Eligible bus masters for memory access */
2122 	if (of_property_read_bool(np, "mem-bus-interface-ahb1"))
2123 		pd->mem_buses |= PL08X_AHB1;
2124 	if (of_property_read_bool(np, "mem-bus-interface-ahb2"))
2125 		pd->mem_buses |= PL08X_AHB2;
2126 	if (!pd->mem_buses) {
2127 		dev_info(&adev->dev, "no bus masters for memory stated, assume all\n");
2128 		pd->mem_buses |= PL08X_AHB1 | PL08X_AHB2;
2129 	}
2130 
2131 	/* Parse the memcpy channel properties */
2132 	ret = of_property_read_u32(np, "memcpy-burst-size", &val);
2133 	if (ret) {
2134 		dev_info(&adev->dev, "no memcpy burst size specified, using 1 byte\n");
2135 		val = 1;
2136 	}
2137 	switch (val) {
2138 	default:
2139 		dev_err(&adev->dev, "illegal burst size for memcpy, set to 1\n");
2140 		/* Fall through */
2141 	case 1:
2142 		cctl_memcpy |= PL080_BSIZE_1 << PL080_CONTROL_SB_SIZE_SHIFT |
2143 			       PL080_BSIZE_1 << PL080_CONTROL_DB_SIZE_SHIFT;
2144 		break;
2145 	case 4:
2146 		cctl_memcpy |= PL080_BSIZE_4 << PL080_CONTROL_SB_SIZE_SHIFT |
2147 			       PL080_BSIZE_4 << PL080_CONTROL_DB_SIZE_SHIFT;
2148 		break;
2149 	case 8:
2150 		cctl_memcpy |= PL080_BSIZE_8 << PL080_CONTROL_SB_SIZE_SHIFT |
2151 			       PL080_BSIZE_8 << PL080_CONTROL_DB_SIZE_SHIFT;
2152 		break;
2153 	case 16:
2154 		cctl_memcpy |= PL080_BSIZE_16 << PL080_CONTROL_SB_SIZE_SHIFT |
2155 			       PL080_BSIZE_16 << PL080_CONTROL_DB_SIZE_SHIFT;
2156 		break;
2157 	case 32:
2158 		cctl_memcpy |= PL080_BSIZE_32 << PL080_CONTROL_SB_SIZE_SHIFT |
2159 			       PL080_BSIZE_32 << PL080_CONTROL_DB_SIZE_SHIFT;
2160 		break;
2161 	case 64:
2162 		cctl_memcpy |= PL080_BSIZE_64 << PL080_CONTROL_SB_SIZE_SHIFT |
2163 			       PL080_BSIZE_64 << PL080_CONTROL_DB_SIZE_SHIFT;
2164 		break;
2165 	case 128:
2166 		cctl_memcpy |= PL080_BSIZE_128 << PL080_CONTROL_SB_SIZE_SHIFT |
2167 			       PL080_BSIZE_128 << PL080_CONTROL_DB_SIZE_SHIFT;
2168 		break;
2169 	case 256:
2170 		cctl_memcpy |= PL080_BSIZE_256 << PL080_CONTROL_SB_SIZE_SHIFT |
2171 			       PL080_BSIZE_256 << PL080_CONTROL_DB_SIZE_SHIFT;
2172 		break;
2173 	}
2174 
2175 	ret = of_property_read_u32(np, "memcpy-bus-width", &val);
2176 	if (ret) {
2177 		dev_info(&adev->dev, "no memcpy bus width specified, using 8 bits\n");
2178 		val = 8;
2179 	}
2180 	switch (val) {
2181 	default:
2182 		dev_err(&adev->dev, "illegal bus width for memcpy, set to 8 bits\n");
2183 		/* Fall through */
2184 	case 8:
2185 		cctl_memcpy |= PL080_WIDTH_8BIT << PL080_CONTROL_SWIDTH_SHIFT |
2186 			       PL080_WIDTH_8BIT << PL080_CONTROL_DWIDTH_SHIFT;
2187 		break;
2188 	case 16:
2189 		cctl_memcpy |= PL080_WIDTH_16BIT << PL080_CONTROL_SWIDTH_SHIFT |
2190 			       PL080_WIDTH_16BIT << PL080_CONTROL_DWIDTH_SHIFT;
2191 		break;
2192 	case 32:
2193 		cctl_memcpy |= PL080_WIDTH_32BIT << PL080_CONTROL_SWIDTH_SHIFT |
2194 			       PL080_WIDTH_32BIT << PL080_CONTROL_DWIDTH_SHIFT;
2195 		break;
2196 	}
2197 
2198 	/* This is currently the only thing making sense */
2199 	cctl_memcpy |= PL080_CONTROL_PROT_SYS;
2200 
2201 	/* Set up memcpy channel */
2202 	pd->memcpy_channel.bus_id = "memcpy";
2203 	pd->memcpy_channel.cctl_memcpy = cctl_memcpy;
2204 	/* Use the buses that can access memory, obviously */
2205 	pd->memcpy_channel.periph_buses = pd->mem_buses;
2206 
2207 	/*
2208 	 * Allocate channel data for all possible slave channels (one
2209 	 * for each possible signal), channels will then be allocated
2210 	 * for a device and have it's AHB interfaces set up at
2211 	 * translation time.
2212 	 */
2213 	chanp = devm_kcalloc(&adev->dev,
2214 			pl08x->vd->signals,
2215 			sizeof(struct pl08x_channel_data),
2216 			GFP_KERNEL);
2217 	if (!chanp)
2218 		return -ENOMEM;
2219 
2220 	pd->slave_channels = chanp;
2221 	for (i = 0; i < pl08x->vd->signals; i++) {
2222 		/* chanp->periph_buses will be assigned at translation */
2223 		chanp->bus_id = kasprintf(GFP_KERNEL, "slave%d", i);
2224 		chanp++;
2225 	}
2226 	pd->num_slave_channels = pl08x->vd->signals;
2227 
2228 	pl08x->pd = pd;
2229 
2230 	return of_dma_controller_register(adev->dev.of_node, pl08x_of_xlate,
2231 					  pl08x);
2232 }
2233 #else
2234 static inline int pl08x_of_probe(struct amba_device *adev,
2235 				 struct pl08x_driver_data *pl08x,
2236 				 struct device_node *np)
2237 {
2238 	return -EINVAL;
2239 }
2240 #endif
2241 
2242 static int pl08x_probe(struct amba_device *adev, const struct amba_id *id)
2243 {
2244 	struct pl08x_driver_data *pl08x;
2245 	const struct vendor_data *vd = id->data;
2246 	struct device_node *np = adev->dev.of_node;
2247 	u32 tsfr_size;
2248 	int ret = 0;
2249 	int i;
2250 
2251 	ret = amba_request_regions(adev, NULL);
2252 	if (ret)
2253 		return ret;
2254 
2255 	/* Ensure that we can do DMA */
2256 	ret = dma_set_mask_and_coherent(&adev->dev, DMA_BIT_MASK(32));
2257 	if (ret)
2258 		goto out_no_pl08x;
2259 
2260 	/* Create the driver state holder */
2261 	pl08x = kzalloc(sizeof(*pl08x), GFP_KERNEL);
2262 	if (!pl08x) {
2263 		ret = -ENOMEM;
2264 		goto out_no_pl08x;
2265 	}
2266 
2267 	/* Assign useful pointers to the driver state */
2268 	pl08x->adev = adev;
2269 	pl08x->vd = vd;
2270 
2271 	/* Initialize memcpy engine */
2272 	dma_cap_set(DMA_MEMCPY, pl08x->memcpy.cap_mask);
2273 	pl08x->memcpy.dev = &adev->dev;
2274 	pl08x->memcpy.device_free_chan_resources = pl08x_free_chan_resources;
2275 	pl08x->memcpy.device_prep_dma_memcpy = pl08x_prep_dma_memcpy;
2276 	pl08x->memcpy.device_prep_dma_interrupt = pl08x_prep_dma_interrupt;
2277 	pl08x->memcpy.device_tx_status = pl08x_dma_tx_status;
2278 	pl08x->memcpy.device_issue_pending = pl08x_issue_pending;
2279 	pl08x->memcpy.device_config = pl08x_config;
2280 	pl08x->memcpy.device_pause = pl08x_pause;
2281 	pl08x->memcpy.device_resume = pl08x_resume;
2282 	pl08x->memcpy.device_terminate_all = pl08x_terminate_all;
2283 	pl08x->memcpy.src_addr_widths = PL80X_DMA_BUSWIDTHS;
2284 	pl08x->memcpy.dst_addr_widths = PL80X_DMA_BUSWIDTHS;
2285 	pl08x->memcpy.directions = BIT(DMA_MEM_TO_MEM);
2286 	pl08x->memcpy.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
2287 
2288 	/* Initialize slave engine */
2289 	dma_cap_set(DMA_SLAVE, pl08x->slave.cap_mask);
2290 	dma_cap_set(DMA_CYCLIC, pl08x->slave.cap_mask);
2291 	pl08x->slave.dev = &adev->dev;
2292 	pl08x->slave.device_free_chan_resources = pl08x_free_chan_resources;
2293 	pl08x->slave.device_prep_dma_interrupt = pl08x_prep_dma_interrupt;
2294 	pl08x->slave.device_tx_status = pl08x_dma_tx_status;
2295 	pl08x->slave.device_issue_pending = pl08x_issue_pending;
2296 	pl08x->slave.device_prep_slave_sg = pl08x_prep_slave_sg;
2297 	pl08x->slave.device_prep_dma_cyclic = pl08x_prep_dma_cyclic;
2298 	pl08x->slave.device_config = pl08x_config;
2299 	pl08x->slave.device_pause = pl08x_pause;
2300 	pl08x->slave.device_resume = pl08x_resume;
2301 	pl08x->slave.device_terminate_all = pl08x_terminate_all;
2302 	pl08x->slave.src_addr_widths = PL80X_DMA_BUSWIDTHS;
2303 	pl08x->slave.dst_addr_widths = PL80X_DMA_BUSWIDTHS;
2304 	pl08x->slave.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
2305 	pl08x->slave.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
2306 
2307 	/* Get the platform data */
2308 	pl08x->pd = dev_get_platdata(&adev->dev);
2309 	if (!pl08x->pd) {
2310 		if (np) {
2311 			ret = pl08x_of_probe(adev, pl08x, np);
2312 			if (ret)
2313 				goto out_no_platdata;
2314 		} else {
2315 			dev_err(&adev->dev, "no platform data supplied\n");
2316 			ret = -EINVAL;
2317 			goto out_no_platdata;
2318 		}
2319 	} else {
2320 		pl08x->slave.filter.map = pl08x->pd->slave_map;
2321 		pl08x->slave.filter.mapcnt = pl08x->pd->slave_map_len;
2322 		pl08x->slave.filter.fn = pl08x_filter_fn;
2323 	}
2324 
2325 	/* By default, AHB1 only.  If dualmaster, from platform */
2326 	pl08x->lli_buses = PL08X_AHB1;
2327 	pl08x->mem_buses = PL08X_AHB1;
2328 	if (pl08x->vd->dualmaster) {
2329 		pl08x->lli_buses = pl08x->pd->lli_buses;
2330 		pl08x->mem_buses = pl08x->pd->mem_buses;
2331 	}
2332 
2333 	if (vd->pl080s)
2334 		pl08x->lli_words = PL080S_LLI_WORDS;
2335 	else
2336 		pl08x->lli_words = PL080_LLI_WORDS;
2337 	tsfr_size = MAX_NUM_TSFR_LLIS * pl08x->lli_words * sizeof(u32);
2338 
2339 	/* A DMA memory pool for LLIs, align on 1-byte boundary */
2340 	pl08x->pool = dma_pool_create(DRIVER_NAME, &pl08x->adev->dev,
2341 						tsfr_size, PL08X_ALIGN, 0);
2342 	if (!pl08x->pool) {
2343 		ret = -ENOMEM;
2344 		goto out_no_lli_pool;
2345 	}
2346 
2347 	pl08x->base = ioremap(adev->res.start, resource_size(&adev->res));
2348 	if (!pl08x->base) {
2349 		ret = -ENOMEM;
2350 		goto out_no_ioremap;
2351 	}
2352 
2353 	/* Turn on the PL08x */
2354 	pl08x_ensure_on(pl08x);
2355 
2356 	/* Attach the interrupt handler */
2357 	writel(0x000000FF, pl08x->base + PL080_ERR_CLEAR);
2358 	writel(0x000000FF, pl08x->base + PL080_TC_CLEAR);
2359 
2360 	ret = request_irq(adev->irq[0], pl08x_irq, 0, DRIVER_NAME, pl08x);
2361 	if (ret) {
2362 		dev_err(&adev->dev, "%s failed to request interrupt %d\n",
2363 			__func__, adev->irq[0]);
2364 		goto out_no_irq;
2365 	}
2366 
2367 	/* Initialize physical channels */
2368 	pl08x->phy_chans = kzalloc((vd->channels * sizeof(*pl08x->phy_chans)),
2369 			GFP_KERNEL);
2370 	if (!pl08x->phy_chans) {
2371 		ret = -ENOMEM;
2372 		goto out_no_phychans;
2373 	}
2374 
2375 	for (i = 0; i < vd->channels; i++) {
2376 		struct pl08x_phy_chan *ch = &pl08x->phy_chans[i];
2377 
2378 		ch->id = i;
2379 		ch->base = pl08x->base + PL080_Cx_BASE(i);
2380 		ch->reg_config = ch->base + vd->config_offset;
2381 		spin_lock_init(&ch->lock);
2382 
2383 		/*
2384 		 * Nomadik variants can have channels that are locked
2385 		 * down for the secure world only. Lock up these channels
2386 		 * by perpetually serving a dummy virtual channel.
2387 		 */
2388 		if (vd->nomadik) {
2389 			u32 val;
2390 
2391 			val = readl(ch->reg_config);
2392 			if (val & (PL080N_CONFIG_ITPROT | PL080N_CONFIG_SECPROT)) {
2393 				dev_info(&adev->dev, "physical channel %d reserved for secure access only\n", i);
2394 				ch->locked = true;
2395 			}
2396 		}
2397 
2398 		dev_dbg(&adev->dev, "physical channel %d is %s\n",
2399 			i, pl08x_phy_channel_busy(ch) ? "BUSY" : "FREE");
2400 	}
2401 
2402 	/* Register as many memcpy channels as there are physical channels */
2403 	ret = pl08x_dma_init_virtual_channels(pl08x, &pl08x->memcpy,
2404 					      pl08x->vd->channels, false);
2405 	if (ret <= 0) {
2406 		dev_warn(&pl08x->adev->dev,
2407 			 "%s failed to enumerate memcpy channels - %d\n",
2408 			 __func__, ret);
2409 		goto out_no_memcpy;
2410 	}
2411 
2412 	/* Register slave channels */
2413 	ret = pl08x_dma_init_virtual_channels(pl08x, &pl08x->slave,
2414 			pl08x->pd->num_slave_channels, true);
2415 	if (ret < 0) {
2416 		dev_warn(&pl08x->adev->dev,
2417 			"%s failed to enumerate slave channels - %d\n",
2418 				__func__, ret);
2419 		goto out_no_slave;
2420 	}
2421 
2422 	ret = dma_async_device_register(&pl08x->memcpy);
2423 	if (ret) {
2424 		dev_warn(&pl08x->adev->dev,
2425 			"%s failed to register memcpy as an async device - %d\n",
2426 			__func__, ret);
2427 		goto out_no_memcpy_reg;
2428 	}
2429 
2430 	ret = dma_async_device_register(&pl08x->slave);
2431 	if (ret) {
2432 		dev_warn(&pl08x->adev->dev,
2433 			"%s failed to register slave as an async device - %d\n",
2434 			__func__, ret);
2435 		goto out_no_slave_reg;
2436 	}
2437 
2438 	amba_set_drvdata(adev, pl08x);
2439 	init_pl08x_debugfs(pl08x);
2440 	dev_info(&pl08x->adev->dev, "DMA: PL%03x%s rev%u at 0x%08llx irq %d\n",
2441 		 amba_part(adev), pl08x->vd->pl080s ? "s" : "", amba_rev(adev),
2442 		 (unsigned long long)adev->res.start, adev->irq[0]);
2443 
2444 	return 0;
2445 
2446 out_no_slave_reg:
2447 	dma_async_device_unregister(&pl08x->memcpy);
2448 out_no_memcpy_reg:
2449 	pl08x_free_virtual_channels(&pl08x->slave);
2450 out_no_slave:
2451 	pl08x_free_virtual_channels(&pl08x->memcpy);
2452 out_no_memcpy:
2453 	kfree(pl08x->phy_chans);
2454 out_no_phychans:
2455 	free_irq(adev->irq[0], pl08x);
2456 out_no_irq:
2457 	iounmap(pl08x->base);
2458 out_no_ioremap:
2459 	dma_pool_destroy(pl08x->pool);
2460 out_no_lli_pool:
2461 out_no_platdata:
2462 	kfree(pl08x);
2463 out_no_pl08x:
2464 	amba_release_regions(adev);
2465 	return ret;
2466 }
2467 
2468 /* PL080 has 8 channels and the PL080 have just 2 */
2469 static struct vendor_data vendor_pl080 = {
2470 	.config_offset = PL080_CH_CONFIG,
2471 	.channels = 8,
2472 	.signals = 16,
2473 	.dualmaster = true,
2474 	.max_transfer_size = PL080_CONTROL_TRANSFER_SIZE_MASK,
2475 };
2476 
2477 static struct vendor_data vendor_nomadik = {
2478 	.config_offset = PL080_CH_CONFIG,
2479 	.channels = 8,
2480 	.signals = 32,
2481 	.dualmaster = true,
2482 	.nomadik = true,
2483 	.max_transfer_size = PL080_CONTROL_TRANSFER_SIZE_MASK,
2484 };
2485 
2486 static struct vendor_data vendor_pl080s = {
2487 	.config_offset = PL080S_CH_CONFIG,
2488 	.channels = 8,
2489 	.signals = 32,
2490 	.pl080s = true,
2491 	.max_transfer_size = PL080S_CONTROL_TRANSFER_SIZE_MASK,
2492 };
2493 
2494 static struct vendor_data vendor_pl081 = {
2495 	.config_offset = PL080_CH_CONFIG,
2496 	.channels = 2,
2497 	.signals = 16,
2498 	.dualmaster = false,
2499 	.max_transfer_size = PL080_CONTROL_TRANSFER_SIZE_MASK,
2500 };
2501 
2502 static struct amba_id pl08x_ids[] = {
2503 	/* Samsung PL080S variant */
2504 	{
2505 		.id	= 0x0a141080,
2506 		.mask	= 0xffffffff,
2507 		.data	= &vendor_pl080s,
2508 	},
2509 	/* PL080 */
2510 	{
2511 		.id	= 0x00041080,
2512 		.mask	= 0x000fffff,
2513 		.data	= &vendor_pl080,
2514 	},
2515 	/* PL081 */
2516 	{
2517 		.id	= 0x00041081,
2518 		.mask	= 0x000fffff,
2519 		.data	= &vendor_pl081,
2520 	},
2521 	/* Nomadik 8815 PL080 variant */
2522 	{
2523 		.id	= 0x00280080,
2524 		.mask	= 0x00ffffff,
2525 		.data	= &vendor_nomadik,
2526 	},
2527 	{ 0, 0 },
2528 };
2529 
2530 MODULE_DEVICE_TABLE(amba, pl08x_ids);
2531 
2532 static struct amba_driver pl08x_amba_driver = {
2533 	.drv.name	= DRIVER_NAME,
2534 	.id_table	= pl08x_ids,
2535 	.probe		= pl08x_probe,
2536 };
2537 
2538 static int __init pl08x_init(void)
2539 {
2540 	int retval;
2541 	retval = amba_driver_register(&pl08x_amba_driver);
2542 	if (retval)
2543 		printk(KERN_WARNING DRIVER_NAME
2544 		       "failed to register as an AMBA device (%d)\n",
2545 		       retval);
2546 	return retval;
2547 }
2548 subsys_initcall(pl08x_init);
2549