1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright 2015 Robert Jarzmik <robert.jarzmik@free.fr>
4 */
5
6#include <linux/err.h>
7#include <linux/module.h>
8#include <linux/init.h>
9#include <linux/types.h>
10#include <linux/interrupt.h>
11#include <linux/dma-mapping.h>
12#include <linux/slab.h>
13#include <linux/dmaengine.h>
14#include <linux/platform_device.h>
15#include <linux/device.h>
16#include <linux/platform_data/mmp_dma.h>
17#include <linux/dmapool.h>
18#include <linux/of.h>
19#include <linux/of_dma.h>
20#include <linux/wait.h>
21#include <linux/dma/pxa-dma.h>
22
23#include "dmaengine.h"
24#include "virt-dma.h"
25
26#define DCSR(n) (0x0000 + ((n) << 2))
27#define DALGN(n) 0x00a0
28#define DINT 0x00f0
29#define DDADR(n) (0x0200 + ((n) << 4))
30#define DSADR(n) (0x0204 + ((n) << 4))
31#define DTADR(n) (0x0208 + ((n) << 4))
32#define DCMD(n) (0x020c + ((n) << 4))
33
34#define PXA_DCSR_RUN BIT(31) /* Run Bit (read / write) */
35#define PXA_DCSR_NODESC BIT(30) /* No-Descriptor Fetch (read / write) */
36#define PXA_DCSR_STOPIRQEN BIT(29) /* Stop Interrupt Enable (R/W) */
37#define PXA_DCSR_REQPEND BIT(8) /* Request Pending (read-only) */
38#define PXA_DCSR_STOPSTATE BIT(3) /* Stop State (read-only) */
39#define PXA_DCSR_ENDINTR BIT(2) /* End Interrupt (read / write) */
40#define PXA_DCSR_STARTINTR BIT(1) /* Start Interrupt (read / write) */
41#define PXA_DCSR_BUSERR BIT(0) /* Bus Error Interrupt (read / write) */
42
43#define PXA_DCSR_EORIRQEN BIT(28) /* End of Receive IRQ Enable (R/W) */
44#define PXA_DCSR_EORJMPEN BIT(27) /* Jump to next descriptor on EOR */
45#define PXA_DCSR_EORSTOPEN BIT(26) /* STOP on an EOR */
46#define PXA_DCSR_SETCMPST BIT(25) /* Set Descriptor Compare Status */
47#define PXA_DCSR_CLRCMPST BIT(24) /* Clear Descriptor Compare Status */
48#define PXA_DCSR_CMPST BIT(10) /* The Descriptor Compare Status */
49#define PXA_DCSR_EORINTR BIT(9) /* The end of Receive */
50
51#define DRCMR_MAPVLD BIT(7) /* Map Valid (read / write) */
52#define DRCMR_CHLNUM 0x1f /* mask for Channel Number (read / write) */
53
54#define DDADR_DESCADDR 0xfffffff0 /* Address of next descriptor (mask) */
55#define DDADR_STOP BIT(0) /* Stop (read / write) */
56
57#define PXA_DCMD_INCSRCADDR BIT(31) /* Source Address Increment Setting. */
58#define PXA_DCMD_INCTRGADDR BIT(30) /* Target Address Increment Setting. */
59#define PXA_DCMD_FLOWSRC BIT(29) /* Flow Control by the source. */
60#define PXA_DCMD_FLOWTRG BIT(28) /* Flow Control by the target. */
61#define PXA_DCMD_STARTIRQEN BIT(22) /* Start Interrupt Enable */
62#define PXA_DCMD_ENDIRQEN BIT(21) /* End Interrupt Enable */
63#define PXA_DCMD_ENDIAN BIT(18) /* Device Endian-ness. */
64#define PXA_DCMD_BURST8 (1 << 16) /* 8 byte burst */
65#define PXA_DCMD_BURST16 (2 << 16) /* 16 byte burst */
66#define PXA_DCMD_BURST32 (3 << 16) /* 32 byte burst */
67#define PXA_DCMD_WIDTH1 (1 << 14) /* 1 byte width */
68#define PXA_DCMD_WIDTH2 (2 << 14) /* 2 byte width (HalfWord) */
69#define PXA_DCMD_WIDTH4 (3 << 14) /* 4 byte width (Word) */
70#define PXA_DCMD_LENGTH 0x01fff /* length mask (max = 8K - 1) */
71
72#define PDMA_ALIGNMENT 3
73#define PDMA_MAX_DESC_BYTES (PXA_DCMD_LENGTH & ~((1 << PDMA_ALIGNMENT) - 1))
74
75struct pxad_desc_hw {
76 u32 ddadr; /* Points to the next descriptor + flags */
77 u32 dsadr; /* DSADR value for the current transfer */
78 u32 dtadr; /* DTADR value for the current transfer */
79 u32 dcmd; /* DCMD value for the current transfer */
80} __aligned(16);
81
82struct pxad_desc_sw {
83 struct virt_dma_desc vd; /* Virtual descriptor */
84 int nb_desc; /* Number of hw. descriptors */
85 size_t len; /* Number of bytes xfered */
86 dma_addr_t first; /* First descriptor's addr */
87
88 /* At least one descriptor has an src/dst address not multiple of 8 */
89 bool misaligned;
90 bool cyclic;
91 struct dma_pool *desc_pool; /* Channel's used allocator */
92
93 struct pxad_desc_hw *hw_desc[] __counted_by(nb_desc);
94 /* DMA coherent descriptors */
95};
96
97struct pxad_phy {
98 int idx;
99 void __iomem *base;
100 struct pxad_chan *vchan;
101};
102
103struct pxad_chan {
104 struct virt_dma_chan vc; /* Virtual channel */
105 u32 drcmr; /* Requestor of the channel */
106 enum pxad_chan_prio prio; /* Required priority of phy */
107 /*
108 * At least one desc_sw in submitted or issued transfers on this channel
109 * has one address such as: addr % 8 != 0. This implies the DALGN
110 * setting on the phy.
111 */
112 bool misaligned;
113 struct dma_slave_config cfg; /* Runtime config */
114
115 /* protected by vc->lock */
116 struct pxad_phy *phy;
117 struct dma_pool *desc_pool; /* Descriptors pool */
118 dma_cookie_t bus_error;
119
120 wait_queue_head_t wq_state;
121};
122
123struct pxad_device {
124 struct dma_device slave;
125 int nr_chans;
126 int nr_requestors;
127 void __iomem *base;
128 struct pxad_phy *phys;
129 spinlock_t phy_lock; /* Phy association */
130#ifdef CONFIG_DEBUG_FS
131 struct dentry *dbgfs_root;
132 struct dentry **dbgfs_chan;
133#endif
134};
135
136#define tx_to_pxad_desc(tx) \
137 container_of(tx, struct pxad_desc_sw, async_tx)
138#define to_pxad_chan(dchan) \
139 container_of(dchan, struct pxad_chan, vc.chan)
140#define to_pxad_dev(dmadev) \
141 container_of(dmadev, struct pxad_device, slave)
142#define to_pxad_sw_desc(_vd) \
143 container_of((_vd), struct pxad_desc_sw, vd)
144
145#define _phy_readl_relaxed(phy, _reg) \
146 readl_relaxed((phy)->base + _reg((phy)->idx))
147#define phy_readl_relaxed(phy, _reg) \
148 ({ \
149 u32 _v; \
150 _v = readl_relaxed((phy)->base + _reg((phy)->idx)); \
151 dev_vdbg(&phy->vchan->vc.chan.dev->device, \
152 "%s(): readl(%s): 0x%08x\n", __func__, #_reg, \
153 _v); \
154 _v; \
155 })
156#define phy_writel(phy, val, _reg) \
157 do { \
158 writel((val), (phy)->base + _reg((phy)->idx)); \
159 dev_vdbg(&phy->vchan->vc.chan.dev->device, \
160 "%s(): writel(0x%08x, %s)\n", \
161 __func__, (u32)(val), #_reg); \
162 } while (0)
163#define phy_writel_relaxed(phy, val, _reg) \
164 do { \
165 writel_relaxed((val), (phy)->base + _reg((phy)->idx)); \
166 dev_vdbg(&phy->vchan->vc.chan.dev->device, \
167 "%s(): writel_relaxed(0x%08x, %s)\n", \
168 __func__, (u32)(val), #_reg); \
169 } while (0)
170
171static unsigned int pxad_drcmr(unsigned int line)
172{
173 if (line < 64)
174 return 0x100 + line * 4;
175 return 0x1000 + line * 4;
176}
177
178static bool pxad_filter_fn(struct dma_chan *chan, void *param);
179
180/*
181 * Debug fs
182 */
183#ifdef CONFIG_DEBUG_FS
184#include <linux/debugfs.h>
185#include <linux/uaccess.h>
186#include <linux/seq_file.h>
187
188static int requester_chan_show(struct seq_file *s, void *p)
189{
190 struct pxad_phy *phy = s->private;
191 int i;
192 u32 drcmr;
193
194 seq_printf(m: s, fmt: "DMA channel %d requester :\n", phy->idx);
195 for (i = 0; i < 70; i++) {
196 drcmr = readl_relaxed(phy->base + pxad_drcmr(i));
197 if ((drcmr & DRCMR_CHLNUM) == phy->idx)
198 seq_printf(m: s, fmt: "\tRequester %d (MAPVLD=%d)\n", i,
199 !!(drcmr & DRCMR_MAPVLD));
200 }
201 return 0;
202}
203
204static inline int dbg_burst_from_dcmd(u32 dcmd)
205{
206 int burst = (dcmd >> 16) & 0x3;
207
208 return burst ? 4 << burst : 0;
209}
210
211static int is_phys_valid(unsigned long addr)
212{
213 return pfn_valid(__phys_to_pfn(addr));
214}
215
216#define PXA_DCSR_STR(flag) (dcsr & PXA_DCSR_##flag ? #flag" " : "")
217#define PXA_DCMD_STR(flag) (dcmd & PXA_DCMD_##flag ? #flag" " : "")
218
219static int descriptors_show(struct seq_file *s, void *p)
220{
221 struct pxad_phy *phy = s->private;
222 int i, max_show = 20, burst, width;
223 u32 dcmd;
224 unsigned long phys_desc, ddadr;
225 struct pxad_desc_hw *desc;
226
227 phys_desc = ddadr = _phy_readl_relaxed(phy, DDADR);
228
229 seq_printf(m: s, fmt: "DMA channel %d descriptors :\n", phy->idx);
230 seq_printf(m: s, fmt: "[%03d] First descriptor unknown\n", 0);
231 for (i = 1; i < max_show && is_phys_valid(addr: phys_desc); i++) {
232 desc = phys_to_virt(address: phys_desc);
233 dcmd = desc->dcmd;
234 burst = dbg_burst_from_dcmd(dcmd);
235 width = (1 << ((dcmd >> 14) & 0x3)) >> 1;
236
237 seq_printf(m: s, fmt: "[%03d] Desc at %08lx(virt %p)\n",
238 i, phys_desc, desc);
239 seq_printf(m: s, fmt: "\tDDADR = %08x\n", desc->ddadr);
240 seq_printf(m: s, fmt: "\tDSADR = %08x\n", desc->dsadr);
241 seq_printf(m: s, fmt: "\tDTADR = %08x\n", desc->dtadr);
242 seq_printf(m: s, fmt: "\tDCMD = %08x (%s%s%s%s%s%s%sburst=%d width=%d len=%d)\n",
243 dcmd,
244 PXA_DCMD_STR(INCSRCADDR), PXA_DCMD_STR(INCTRGADDR),
245 PXA_DCMD_STR(FLOWSRC), PXA_DCMD_STR(FLOWTRG),
246 PXA_DCMD_STR(STARTIRQEN), PXA_DCMD_STR(ENDIRQEN),
247 PXA_DCMD_STR(ENDIAN), burst, width,
248 dcmd & PXA_DCMD_LENGTH);
249 phys_desc = desc->ddadr;
250 }
251 if (i == max_show)
252 seq_printf(m: s, fmt: "[%03d] Desc at %08lx ... max display reached\n",
253 i, phys_desc);
254 else
255 seq_printf(m: s, fmt: "[%03d] Desc at %08lx is %s\n",
256 i, phys_desc, phys_desc == DDADR_STOP ?
257 "DDADR_STOP" : "invalid");
258
259 return 0;
260}
261
262static int chan_state_show(struct seq_file *s, void *p)
263{
264 struct pxad_phy *phy = s->private;
265 u32 dcsr, dcmd;
266 int burst, width;
267 static const char * const str_prio[] = {
268 "high", "normal", "low", "invalid"
269 };
270
271 dcsr = _phy_readl_relaxed(phy, DCSR);
272 dcmd = _phy_readl_relaxed(phy, DCMD);
273 burst = dbg_burst_from_dcmd(dcmd);
274 width = (1 << ((dcmd >> 14) & 0x3)) >> 1;
275
276 seq_printf(m: s, fmt: "DMA channel %d\n", phy->idx);
277 seq_printf(m: s, fmt: "\tPriority : %s\n",
278 str_prio[(phy->idx & 0xf) / 4]);
279 seq_printf(m: s, fmt: "\tUnaligned transfer bit: %s\n",
280 _phy_readl_relaxed(phy, DALGN) & BIT(phy->idx) ?
281 "yes" : "no");
282 seq_printf(m: s, fmt: "\tDCSR = %08x (%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s)\n",
283 dcsr, PXA_DCSR_STR(RUN), PXA_DCSR_STR(NODESC),
284 PXA_DCSR_STR(STOPIRQEN), PXA_DCSR_STR(EORIRQEN),
285 PXA_DCSR_STR(EORJMPEN), PXA_DCSR_STR(EORSTOPEN),
286 PXA_DCSR_STR(SETCMPST), PXA_DCSR_STR(CLRCMPST),
287 PXA_DCSR_STR(CMPST), PXA_DCSR_STR(EORINTR),
288 PXA_DCSR_STR(REQPEND), PXA_DCSR_STR(STOPSTATE),
289 PXA_DCSR_STR(ENDINTR), PXA_DCSR_STR(STARTINTR),
290 PXA_DCSR_STR(BUSERR));
291
292 seq_printf(m: s, fmt: "\tDCMD = %08x (%s%s%s%s%s%s%sburst=%d width=%d len=%d)\n",
293 dcmd,
294 PXA_DCMD_STR(INCSRCADDR), PXA_DCMD_STR(INCTRGADDR),
295 PXA_DCMD_STR(FLOWSRC), PXA_DCMD_STR(FLOWTRG),
296 PXA_DCMD_STR(STARTIRQEN), PXA_DCMD_STR(ENDIRQEN),
297 PXA_DCMD_STR(ENDIAN), burst, width, dcmd & PXA_DCMD_LENGTH);
298 seq_printf(m: s, fmt: "\tDSADR = %08x\n", _phy_readl_relaxed(phy, DSADR));
299 seq_printf(m: s, fmt: "\tDTADR = %08x\n", _phy_readl_relaxed(phy, DTADR));
300 seq_printf(m: s, fmt: "\tDDADR = %08x\n", _phy_readl_relaxed(phy, DDADR));
301
302 return 0;
303}
304
305static int state_show(struct seq_file *s, void *p)
306{
307 struct pxad_device *pdev = s->private;
308
309 /* basic device status */
310 seq_puts(m: s, s: "DMA engine status\n");
311 seq_printf(m: s, fmt: "\tChannel number: %d\n", pdev->nr_chans);
312
313 return 0;
314}
315
316DEFINE_SHOW_ATTRIBUTE(state);
317DEFINE_SHOW_ATTRIBUTE(chan_state);
318DEFINE_SHOW_ATTRIBUTE(descriptors);
319DEFINE_SHOW_ATTRIBUTE(requester_chan);
320
321static struct dentry *pxad_dbg_alloc_chan(struct pxad_device *pdev,
322 int ch, struct dentry *chandir)
323{
324 char chan_name[11];
325 struct dentry *chan;
326 void *dt;
327
328 scnprintf(buf: chan_name, size: sizeof(chan_name), fmt: "%d", ch);
329 chan = debugfs_create_dir(name: chan_name, parent: chandir);
330 dt = (void *)&pdev->phys[ch];
331
332 debugfs_create_file(name: "state", mode: 0400, parent: chan, data: dt, fops: &chan_state_fops);
333 debugfs_create_file(name: "descriptors", mode: 0400, parent: chan, data: dt, fops: &descriptors_fops);
334 debugfs_create_file(name: "requesters", mode: 0400, parent: chan, data: dt, fops: &requester_chan_fops);
335
336 return chan;
337}
338
339static void pxad_init_debugfs(struct pxad_device *pdev)
340{
341 int i;
342 struct dentry *chandir;
343
344 pdev->dbgfs_chan =
345 kmalloc_array(n: pdev->nr_chans, size: sizeof(struct dentry *),
346 GFP_KERNEL);
347 if (!pdev->dbgfs_chan)
348 return;
349
350 pdev->dbgfs_root = debugfs_create_dir(name: dev_name(dev: pdev->slave.dev), NULL);
351
352 debugfs_create_file(name: "state", mode: 0400, parent: pdev->dbgfs_root, data: pdev, fops: &state_fops);
353
354 chandir = debugfs_create_dir(name: "channels", parent: pdev->dbgfs_root);
355
356 for (i = 0; i < pdev->nr_chans; i++)
357 pdev->dbgfs_chan[i] = pxad_dbg_alloc_chan(pdev, ch: i, chandir);
358}
359
360static void pxad_cleanup_debugfs(struct pxad_device *pdev)
361{
362 debugfs_remove_recursive(dentry: pdev->dbgfs_root);
363}
364#else
365static inline void pxad_init_debugfs(struct pxad_device *pdev) {}
366static inline void pxad_cleanup_debugfs(struct pxad_device *pdev) {}
367#endif
368
369static struct pxad_phy *lookup_phy(struct pxad_chan *pchan)
370{
371 int prio, i;
372 struct pxad_device *pdev = to_pxad_dev(pchan->vc.chan.device);
373 struct pxad_phy *phy, *found = NULL;
374 unsigned long flags;
375
376 /*
377 * dma channel priorities
378 * ch 0 - 3, 16 - 19 <--> (0)
379 * ch 4 - 7, 20 - 23 <--> (1)
380 * ch 8 - 11, 24 - 27 <--> (2)
381 * ch 12 - 15, 28 - 31 <--> (3)
382 */
383
384 spin_lock_irqsave(&pdev->phy_lock, flags);
385 for (prio = pchan->prio; prio >= PXAD_PRIO_HIGHEST; prio--) {
386 for (i = 0; i < pdev->nr_chans; i++) {
387 if (prio != (i & 0xf) >> 2)
388 continue;
389 phy = &pdev->phys[i];
390 if (!phy->vchan) {
391 phy->vchan = pchan;
392 found = phy;
393 goto out_unlock;
394 }
395 }
396 }
397
398out_unlock:
399 spin_unlock_irqrestore(lock: &pdev->phy_lock, flags);
400 dev_dbg(&pchan->vc.chan.dev->device,
401 "%s(): phy=%p(%d)\n", __func__, found,
402 found ? found->idx : -1);
403
404 return found;
405}
406
407static void pxad_free_phy(struct pxad_chan *chan)
408{
409 struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
410 unsigned long flags;
411 u32 reg;
412
413 dev_dbg(&chan->vc.chan.dev->device,
414 "%s(): freeing\n", __func__);
415 if (!chan->phy)
416 return;
417
418 /* clear the channel mapping in DRCMR */
419 if (chan->drcmr <= pdev->nr_requestors) {
420 reg = pxad_drcmr(line: chan->drcmr);
421 writel_relaxed(0, chan->phy->base + reg);
422 }
423
424 spin_lock_irqsave(&pdev->phy_lock, flags);
425 chan->phy->vchan = NULL;
426 chan->phy = NULL;
427 spin_unlock_irqrestore(lock: &pdev->phy_lock, flags);
428}
429
430static bool is_chan_running(struct pxad_chan *chan)
431{
432 u32 dcsr;
433 struct pxad_phy *phy = chan->phy;
434
435 if (!phy)
436 return false;
437 dcsr = phy_readl_relaxed(phy, DCSR);
438 return dcsr & PXA_DCSR_RUN;
439}
440
441static bool is_running_chan_misaligned(struct pxad_chan *chan)
442{
443 u32 dalgn;
444
445 BUG_ON(!chan->phy);
446 dalgn = phy_readl_relaxed(chan->phy, DALGN);
447 return dalgn & (BIT(chan->phy->idx));
448}
449
450static void phy_enable(struct pxad_phy *phy, bool misaligned)
451{
452 struct pxad_device *pdev;
453 u32 reg, dalgn;
454
455 if (!phy->vchan)
456 return;
457
458 dev_dbg(&phy->vchan->vc.chan.dev->device,
459 "%s(); phy=%p(%d) misaligned=%d\n", __func__,
460 phy, phy->idx, misaligned);
461
462 pdev = to_pxad_dev(phy->vchan->vc.chan.device);
463 if (phy->vchan->drcmr <= pdev->nr_requestors) {
464 reg = pxad_drcmr(line: phy->vchan->drcmr);
465 writel_relaxed(DRCMR_MAPVLD | phy->idx, phy->base + reg);
466 }
467
468 dalgn = phy_readl_relaxed(phy, DALGN);
469 if (misaligned)
470 dalgn |= BIT(phy->idx);
471 else
472 dalgn &= ~BIT(phy->idx);
473 phy_writel_relaxed(phy, dalgn, DALGN);
474
475 phy_writel(phy, PXA_DCSR_STOPIRQEN | PXA_DCSR_ENDINTR |
476 PXA_DCSR_BUSERR | PXA_DCSR_RUN, DCSR);
477}
478
479static void phy_disable(struct pxad_phy *phy)
480{
481 u32 dcsr;
482
483 if (!phy)
484 return;
485
486 dcsr = phy_readl_relaxed(phy, DCSR);
487 dev_dbg(&phy->vchan->vc.chan.dev->device,
488 "%s(): phy=%p(%d)\n", __func__, phy, phy->idx);
489 phy_writel(phy, dcsr & ~PXA_DCSR_RUN & ~PXA_DCSR_STOPIRQEN, DCSR);
490}
491
492static void pxad_launch_chan(struct pxad_chan *chan,
493 struct pxad_desc_sw *desc)
494{
495 dev_dbg(&chan->vc.chan.dev->device,
496 "%s(): desc=%p\n", __func__, desc);
497 if (!chan->phy) {
498 chan->phy = lookup_phy(pchan: chan);
499 if (!chan->phy) {
500 dev_dbg(&chan->vc.chan.dev->device,
501 "%s(): no free dma channel\n", __func__);
502 return;
503 }
504 }
505 chan->bus_error = 0;
506
507 /*
508 * Program the descriptor's address into the DMA controller,
509 * then start the DMA transaction
510 */
511 phy_writel(chan->phy, desc->first, DDADR);
512 phy_enable(phy: chan->phy, misaligned: chan->misaligned);
513 wake_up(&chan->wq_state);
514}
515
516static void set_updater_desc(struct pxad_desc_sw *sw_desc,
517 unsigned long flags)
518{
519 struct pxad_desc_hw *updater =
520 sw_desc->hw_desc[sw_desc->nb_desc - 1];
521 dma_addr_t dma = sw_desc->hw_desc[sw_desc->nb_desc - 2]->ddadr;
522
523 updater->ddadr = DDADR_STOP;
524 updater->dsadr = dma;
525 updater->dtadr = dma + 8;
526 updater->dcmd = PXA_DCMD_WIDTH4 | PXA_DCMD_BURST32 |
527 (PXA_DCMD_LENGTH & sizeof(u32));
528 if (flags & DMA_PREP_INTERRUPT)
529 updater->dcmd |= PXA_DCMD_ENDIRQEN;
530 if (sw_desc->cyclic)
531 sw_desc->hw_desc[sw_desc->nb_desc - 2]->ddadr = sw_desc->first;
532}
533
534static bool is_desc_completed(struct virt_dma_desc *vd)
535{
536 struct pxad_desc_sw *sw_desc = to_pxad_sw_desc(vd);
537 struct pxad_desc_hw *updater =
538 sw_desc->hw_desc[sw_desc->nb_desc - 1];
539
540 return updater->dtadr != (updater->dsadr + 8);
541}
542
543static void pxad_desc_chain(struct virt_dma_desc *vd1,
544 struct virt_dma_desc *vd2)
545{
546 struct pxad_desc_sw *desc1 = to_pxad_sw_desc(vd1);
547 struct pxad_desc_sw *desc2 = to_pxad_sw_desc(vd2);
548 dma_addr_t dma_to_chain;
549
550 dma_to_chain = desc2->first;
551 desc1->hw_desc[desc1->nb_desc - 1]->ddadr = dma_to_chain;
552}
553
554static bool pxad_try_hotchain(struct virt_dma_chan *vc,
555 struct virt_dma_desc *vd)
556{
557 struct virt_dma_desc *vd_last_issued = NULL;
558 struct pxad_chan *chan = to_pxad_chan(&vc->chan);
559
560 /*
561 * Attempt to hot chain the tx if the phy is still running. This is
562 * considered successful only if either the channel is still running
563 * after the chaining, or if the chained transfer is completed after
564 * having been hot chained.
565 * A change of alignment is not allowed, and forbids hotchaining.
566 */
567 if (is_chan_running(chan)) {
568 BUG_ON(list_empty(&vc->desc_issued));
569
570 if (!is_running_chan_misaligned(chan) &&
571 to_pxad_sw_desc(vd)->misaligned)
572 return false;
573
574 vd_last_issued = list_entry(vc->desc_issued.prev,
575 struct virt_dma_desc, node);
576 pxad_desc_chain(vd1: vd_last_issued, vd2: vd);
577 if (is_chan_running(chan) || is_desc_completed(vd))
578 return true;
579 }
580
581 return false;
582}
583
584static unsigned int clear_chan_irq(struct pxad_phy *phy)
585{
586 u32 dcsr;
587 u32 dint = readl(addr: phy->base + DINT);
588
589 if (!(dint & BIT(phy->idx)))
590 return PXA_DCSR_RUN;
591
592 /* clear irq */
593 dcsr = phy_readl_relaxed(phy, DCSR);
594 phy_writel(phy, dcsr, DCSR);
595 if ((dcsr & PXA_DCSR_BUSERR) && (phy->vchan))
596 dev_warn(&phy->vchan->vc.chan.dev->device,
597 "%s(chan=%p): PXA_DCSR_BUSERR\n",
598 __func__, &phy->vchan);
599
600 return dcsr & ~PXA_DCSR_RUN;
601}
602
603static irqreturn_t pxad_chan_handler(int irq, void *dev_id)
604{
605 struct pxad_phy *phy = dev_id;
606 struct pxad_chan *chan = phy->vchan;
607 struct virt_dma_desc *vd, *tmp;
608 unsigned int dcsr;
609 bool vd_completed;
610 dma_cookie_t last_started = 0;
611
612 BUG_ON(!chan);
613
614 dcsr = clear_chan_irq(phy);
615 if (dcsr & PXA_DCSR_RUN)
616 return IRQ_NONE;
617
618 spin_lock(lock: &chan->vc.lock);
619 list_for_each_entry_safe(vd, tmp, &chan->vc.desc_issued, node) {
620 vd_completed = is_desc_completed(vd);
621 dev_dbg(&chan->vc.chan.dev->device,
622 "%s(): checking txd %p[%x]: completed=%d dcsr=0x%x\n",
623 __func__, vd, vd->tx.cookie, vd_completed,
624 dcsr);
625 last_started = vd->tx.cookie;
626 if (to_pxad_sw_desc(vd)->cyclic) {
627 vchan_cyclic_callback(vd);
628 break;
629 }
630 if (vd_completed) {
631 list_del(entry: &vd->node);
632 vchan_cookie_complete(vd);
633 } else {
634 break;
635 }
636 }
637
638 if (dcsr & PXA_DCSR_BUSERR) {
639 chan->bus_error = last_started;
640 phy_disable(phy);
641 }
642
643 if (!chan->bus_error && dcsr & PXA_DCSR_STOPSTATE) {
644 dev_dbg(&chan->vc.chan.dev->device,
645 "%s(): channel stopped, submitted_empty=%d issued_empty=%d",
646 __func__,
647 list_empty(&chan->vc.desc_submitted),
648 list_empty(&chan->vc.desc_issued));
649 phy_writel_relaxed(phy, dcsr & ~PXA_DCSR_STOPIRQEN, DCSR);
650
651 if (list_empty(head: &chan->vc.desc_issued)) {
652 chan->misaligned =
653 !list_empty(head: &chan->vc.desc_submitted);
654 } else {
655 vd = list_first_entry(&chan->vc.desc_issued,
656 struct virt_dma_desc, node);
657 pxad_launch_chan(chan, to_pxad_sw_desc(vd));
658 }
659 }
660 spin_unlock(lock: &chan->vc.lock);
661 wake_up(&chan->wq_state);
662
663 return IRQ_HANDLED;
664}
665
666static irqreturn_t pxad_int_handler(int irq, void *dev_id)
667{
668 struct pxad_device *pdev = dev_id;
669 struct pxad_phy *phy;
670 u32 dint = readl(addr: pdev->base + DINT);
671 int i, ret = IRQ_NONE;
672
673 while (dint) {
674 i = __ffs(dint);
675 dint &= (dint - 1);
676 phy = &pdev->phys[i];
677 if (pxad_chan_handler(irq, dev_id: phy) == IRQ_HANDLED)
678 ret = IRQ_HANDLED;
679 }
680
681 return ret;
682}
683
684static int pxad_alloc_chan_resources(struct dma_chan *dchan)
685{
686 struct pxad_chan *chan = to_pxad_chan(dchan);
687 struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
688
689 if (chan->desc_pool)
690 return 1;
691
692 chan->desc_pool = dma_pool_create(name: dma_chan_name(chan: dchan),
693 dev: pdev->slave.dev,
694 size: sizeof(struct pxad_desc_hw),
695 align: __alignof__(struct pxad_desc_hw),
696 allocation: 0);
697 if (!chan->desc_pool) {
698 dev_err(&chan->vc.chan.dev->device,
699 "%s(): unable to allocate descriptor pool\n",
700 __func__);
701 return -ENOMEM;
702 }
703
704 return 1;
705}
706
707static void pxad_free_chan_resources(struct dma_chan *dchan)
708{
709 struct pxad_chan *chan = to_pxad_chan(dchan);
710
711 vchan_free_chan_resources(vc: &chan->vc);
712 dma_pool_destroy(pool: chan->desc_pool);
713 chan->desc_pool = NULL;
714
715 chan->drcmr = U32_MAX;
716 chan->prio = PXAD_PRIO_LOWEST;
717}
718
719static void pxad_free_desc(struct virt_dma_desc *vd)
720{
721 int i;
722 dma_addr_t dma;
723 struct pxad_desc_sw *sw_desc = to_pxad_sw_desc(vd);
724
725 for (i = sw_desc->nb_desc - 1; i >= 0; i--) {
726 if (i > 0)
727 dma = sw_desc->hw_desc[i - 1]->ddadr;
728 else
729 dma = sw_desc->first;
730 dma_pool_free(pool: sw_desc->desc_pool,
731 vaddr: sw_desc->hw_desc[i], addr: dma);
732 }
733 sw_desc->nb_desc = 0;
734 kfree(objp: sw_desc);
735}
736
737static struct pxad_desc_sw *
738pxad_alloc_desc(struct pxad_chan *chan, unsigned int nb_hw_desc)
739{
740 struct pxad_desc_sw *sw_desc;
741 dma_addr_t dma;
742 void *desc;
743 int i;
744
745 sw_desc = kzalloc(struct_size(sw_desc, hw_desc, nb_hw_desc),
746 GFP_NOWAIT);
747 if (!sw_desc)
748 return NULL;
749 sw_desc->desc_pool = chan->desc_pool;
750
751 for (i = 0; i < nb_hw_desc; i++) {
752 desc = dma_pool_alloc(pool: sw_desc->desc_pool, GFP_NOWAIT, handle: &dma);
753 if (!desc) {
754 dev_err(&chan->vc.chan.dev->device,
755 "%s(): Couldn't allocate the %dth hw_desc from dma_pool %p\n",
756 __func__, i, sw_desc->desc_pool);
757 goto err;
758 }
759
760 sw_desc->nb_desc++;
761 sw_desc->hw_desc[i] = desc;
762
763 if (i == 0)
764 sw_desc->first = dma;
765 else
766 sw_desc->hw_desc[i - 1]->ddadr = dma;
767 }
768
769 return sw_desc;
770err:
771 pxad_free_desc(vd: &sw_desc->vd);
772 return NULL;
773}
774
775static dma_cookie_t pxad_tx_submit(struct dma_async_tx_descriptor *tx)
776{
777 struct virt_dma_chan *vc = to_virt_chan(chan: tx->chan);
778 struct pxad_chan *chan = to_pxad_chan(&vc->chan);
779 struct virt_dma_desc *vd_chained = NULL,
780 *vd = container_of(tx, struct virt_dma_desc, tx);
781 dma_cookie_t cookie;
782 unsigned long flags;
783
784 set_updater_desc(to_pxad_sw_desc(vd), flags: tx->flags);
785
786 spin_lock_irqsave(&vc->lock, flags);
787 cookie = dma_cookie_assign(tx);
788
789 if (list_empty(head: &vc->desc_submitted) && pxad_try_hotchain(vc, vd)) {
790 list_move_tail(list: &vd->node, head: &vc->desc_issued);
791 dev_dbg(&chan->vc.chan.dev->device,
792 "%s(): txd %p[%x]: submitted (hot linked)\n",
793 __func__, vd, cookie);
794 goto out;
795 }
796
797 /*
798 * Fallback to placing the tx in the submitted queue
799 */
800 if (!list_empty(head: &vc->desc_submitted)) {
801 vd_chained = list_entry(vc->desc_submitted.prev,
802 struct virt_dma_desc, node);
803 /*
804 * Only chain the descriptors if no new misalignment is
805 * introduced. If a new misalignment is chained, let the channel
806 * stop, and be relaunched in misalign mode from the irq
807 * handler.
808 */
809 if (chan->misaligned || !to_pxad_sw_desc(vd)->misaligned)
810 pxad_desc_chain(vd1: vd_chained, vd2: vd);
811 else
812 vd_chained = NULL;
813 }
814 dev_dbg(&chan->vc.chan.dev->device,
815 "%s(): txd %p[%x]: submitted (%s linked)\n",
816 __func__, vd, cookie, vd_chained ? "cold" : "not");
817 list_move_tail(list: &vd->node, head: &vc->desc_submitted);
818 chan->misaligned |= to_pxad_sw_desc(vd)->misaligned;
819
820out:
821 spin_unlock_irqrestore(lock: &vc->lock, flags);
822 return cookie;
823}
824
825static void pxad_issue_pending(struct dma_chan *dchan)
826{
827 struct pxad_chan *chan = to_pxad_chan(dchan);
828 struct virt_dma_desc *vd_first;
829 unsigned long flags;
830
831 spin_lock_irqsave(&chan->vc.lock, flags);
832 if (list_empty(head: &chan->vc.desc_submitted))
833 goto out;
834
835 vd_first = list_first_entry(&chan->vc.desc_submitted,
836 struct virt_dma_desc, node);
837 dev_dbg(&chan->vc.chan.dev->device,
838 "%s(): txd %p[%x]", __func__, vd_first, vd_first->tx.cookie);
839
840 vchan_issue_pending(vc: &chan->vc);
841 if (!pxad_try_hotchain(vc: &chan->vc, vd: vd_first))
842 pxad_launch_chan(chan, to_pxad_sw_desc(vd_first));
843out:
844 spin_unlock_irqrestore(lock: &chan->vc.lock, flags);
845}
846
847static inline struct dma_async_tx_descriptor *
848pxad_tx_prep(struct virt_dma_chan *vc, struct virt_dma_desc *vd,
849 unsigned long tx_flags)
850{
851 struct dma_async_tx_descriptor *tx;
852 struct pxad_chan *chan = container_of(vc, struct pxad_chan, vc);
853
854 INIT_LIST_HEAD(list: &vd->node);
855 tx = vchan_tx_prep(vc, vd, tx_flags);
856 tx->tx_submit = pxad_tx_submit;
857 dev_dbg(&chan->vc.chan.dev->device,
858 "%s(): vc=%p txd=%p[%x] flags=0x%lx\n", __func__,
859 vc, vd, vd->tx.cookie,
860 tx_flags);
861
862 return tx;
863}
864
865static void pxad_get_config(struct pxad_chan *chan,
866 enum dma_transfer_direction dir,
867 u32 *dcmd, u32 *dev_src, u32 *dev_dst)
868{
869 u32 maxburst = 0, dev_addr = 0;
870 enum dma_slave_buswidth width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
871 struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
872
873 *dcmd = 0;
874 if (dir == DMA_DEV_TO_MEM) {
875 maxburst = chan->cfg.src_maxburst;
876 width = chan->cfg.src_addr_width;
877 dev_addr = chan->cfg.src_addr;
878 *dev_src = dev_addr;
879 *dcmd |= PXA_DCMD_INCTRGADDR;
880 if (chan->drcmr <= pdev->nr_requestors)
881 *dcmd |= PXA_DCMD_FLOWSRC;
882 }
883 if (dir == DMA_MEM_TO_DEV) {
884 maxburst = chan->cfg.dst_maxburst;
885 width = chan->cfg.dst_addr_width;
886 dev_addr = chan->cfg.dst_addr;
887 *dev_dst = dev_addr;
888 *dcmd |= PXA_DCMD_INCSRCADDR;
889 if (chan->drcmr <= pdev->nr_requestors)
890 *dcmd |= PXA_DCMD_FLOWTRG;
891 }
892 if (dir == DMA_MEM_TO_MEM)
893 *dcmd |= PXA_DCMD_BURST32 | PXA_DCMD_INCTRGADDR |
894 PXA_DCMD_INCSRCADDR;
895
896 dev_dbg(&chan->vc.chan.dev->device,
897 "%s(): dev_addr=0x%x maxburst=%d width=%d dir=%d\n",
898 __func__, dev_addr, maxburst, width, dir);
899
900 if (width == DMA_SLAVE_BUSWIDTH_1_BYTE)
901 *dcmd |= PXA_DCMD_WIDTH1;
902 else if (width == DMA_SLAVE_BUSWIDTH_2_BYTES)
903 *dcmd |= PXA_DCMD_WIDTH2;
904 else if (width == DMA_SLAVE_BUSWIDTH_4_BYTES)
905 *dcmd |= PXA_DCMD_WIDTH4;
906
907 if (maxburst == 8)
908 *dcmd |= PXA_DCMD_BURST8;
909 else if (maxburst == 16)
910 *dcmd |= PXA_DCMD_BURST16;
911 else if (maxburst == 32)
912 *dcmd |= PXA_DCMD_BURST32;
913}
914
915static struct dma_async_tx_descriptor *
916pxad_prep_memcpy(struct dma_chan *dchan,
917 dma_addr_t dma_dst, dma_addr_t dma_src,
918 size_t len, unsigned long flags)
919{
920 struct pxad_chan *chan = to_pxad_chan(dchan);
921 struct pxad_desc_sw *sw_desc;
922 struct pxad_desc_hw *hw_desc;
923 u32 dcmd;
924 unsigned int i, nb_desc = 0;
925 size_t copy;
926
927 if (!dchan || !len)
928 return NULL;
929
930 dev_dbg(&chan->vc.chan.dev->device,
931 "%s(): dma_dst=0x%lx dma_src=0x%lx len=%zu flags=%lx\n",
932 __func__, (unsigned long)dma_dst, (unsigned long)dma_src,
933 len, flags);
934 pxad_get_config(chan, dir: DMA_MEM_TO_MEM, dcmd: &dcmd, NULL, NULL);
935
936 nb_desc = DIV_ROUND_UP(len, PDMA_MAX_DESC_BYTES);
937 sw_desc = pxad_alloc_desc(chan, nb_hw_desc: nb_desc + 1);
938 if (!sw_desc)
939 return NULL;
940 sw_desc->len = len;
941
942 if (!IS_ALIGNED(dma_src, 1 << PDMA_ALIGNMENT) ||
943 !IS_ALIGNED(dma_dst, 1 << PDMA_ALIGNMENT))
944 sw_desc->misaligned = true;
945
946 i = 0;
947 do {
948 hw_desc = sw_desc->hw_desc[i++];
949 copy = min_t(size_t, len, PDMA_MAX_DESC_BYTES);
950 hw_desc->dcmd = dcmd | (PXA_DCMD_LENGTH & copy);
951 hw_desc->dsadr = dma_src;
952 hw_desc->dtadr = dma_dst;
953 len -= copy;
954 dma_src += copy;
955 dma_dst += copy;
956 } while (len);
957 set_updater_desc(sw_desc, flags);
958
959 return pxad_tx_prep(vc: &chan->vc, vd: &sw_desc->vd, tx_flags: flags);
960}
961
962static struct dma_async_tx_descriptor *
963pxad_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
964 unsigned int sg_len, enum dma_transfer_direction dir,
965 unsigned long flags, void *context)
966{
967 struct pxad_chan *chan = to_pxad_chan(dchan);
968 struct pxad_desc_sw *sw_desc;
969 size_t len, avail;
970 struct scatterlist *sg;
971 dma_addr_t dma;
972 u32 dcmd, dsadr = 0, dtadr = 0;
973 unsigned int nb_desc = 0, i, j = 0;
974
975 if ((sgl == NULL) || (sg_len == 0))
976 return NULL;
977
978 pxad_get_config(chan, dir, dcmd: &dcmd, dev_src: &dsadr, dev_dst: &dtadr);
979 dev_dbg(&chan->vc.chan.dev->device,
980 "%s(): dir=%d flags=%lx\n", __func__, dir, flags);
981
982 for_each_sg(sgl, sg, sg_len, i)
983 nb_desc += DIV_ROUND_UP(sg_dma_len(sg), PDMA_MAX_DESC_BYTES);
984 sw_desc = pxad_alloc_desc(chan, nb_hw_desc: nb_desc + 1);
985 if (!sw_desc)
986 return NULL;
987
988 for_each_sg(sgl, sg, sg_len, i) {
989 dma = sg_dma_address(sg);
990 avail = sg_dma_len(sg);
991 sw_desc->len += avail;
992
993 do {
994 len = min_t(size_t, avail, PDMA_MAX_DESC_BYTES);
995 if (dma & 0x7)
996 sw_desc->misaligned = true;
997
998 sw_desc->hw_desc[j]->dcmd =
999 dcmd | (PXA_DCMD_LENGTH & len);
1000 sw_desc->hw_desc[j]->dsadr = dsadr ? dsadr : dma;
1001 sw_desc->hw_desc[j++]->dtadr = dtadr ? dtadr : dma;
1002
1003 dma += len;
1004 avail -= len;
1005 } while (avail);
1006 }
1007 set_updater_desc(sw_desc, flags);
1008
1009 return pxad_tx_prep(vc: &chan->vc, vd: &sw_desc->vd, tx_flags: flags);
1010}
1011
1012static struct dma_async_tx_descriptor *
1013pxad_prep_dma_cyclic(struct dma_chan *dchan,
1014 dma_addr_t buf_addr, size_t len, size_t period_len,
1015 enum dma_transfer_direction dir, unsigned long flags)
1016{
1017 struct pxad_chan *chan = to_pxad_chan(dchan);
1018 struct pxad_desc_sw *sw_desc;
1019 struct pxad_desc_hw **phw_desc;
1020 dma_addr_t dma;
1021 u32 dcmd, dsadr = 0, dtadr = 0;
1022 unsigned int nb_desc = 0;
1023
1024 if (!dchan || !len || !period_len)
1025 return NULL;
1026 if ((dir != DMA_DEV_TO_MEM) && (dir != DMA_MEM_TO_DEV)) {
1027 dev_err(&chan->vc.chan.dev->device,
1028 "Unsupported direction for cyclic DMA\n");
1029 return NULL;
1030 }
1031 /* the buffer length must be a multiple of period_len */
1032 if (len % period_len != 0 || period_len > PDMA_MAX_DESC_BYTES ||
1033 !IS_ALIGNED(period_len, 1 << PDMA_ALIGNMENT))
1034 return NULL;
1035
1036 pxad_get_config(chan, dir, dcmd: &dcmd, dev_src: &dsadr, dev_dst: &dtadr);
1037 dcmd |= PXA_DCMD_ENDIRQEN | (PXA_DCMD_LENGTH & period_len);
1038 dev_dbg(&chan->vc.chan.dev->device,
1039 "%s(): buf_addr=0x%lx len=%zu period=%zu dir=%d flags=%lx\n",
1040 __func__, (unsigned long)buf_addr, len, period_len, dir, flags);
1041
1042 nb_desc = DIV_ROUND_UP(period_len, PDMA_MAX_DESC_BYTES);
1043 nb_desc *= DIV_ROUND_UP(len, period_len);
1044 sw_desc = pxad_alloc_desc(chan, nb_hw_desc: nb_desc + 1);
1045 if (!sw_desc)
1046 return NULL;
1047 sw_desc->cyclic = true;
1048 sw_desc->len = len;
1049
1050 phw_desc = sw_desc->hw_desc;
1051 dma = buf_addr;
1052 do {
1053 phw_desc[0]->dsadr = dsadr ? dsadr : dma;
1054 phw_desc[0]->dtadr = dtadr ? dtadr : dma;
1055 phw_desc[0]->dcmd = dcmd;
1056 phw_desc++;
1057 dma += period_len;
1058 len -= period_len;
1059 } while (len);
1060 set_updater_desc(sw_desc, flags);
1061
1062 return pxad_tx_prep(vc: &chan->vc, vd: &sw_desc->vd, tx_flags: flags);
1063}
1064
1065static int pxad_config(struct dma_chan *dchan,
1066 struct dma_slave_config *cfg)
1067{
1068 struct pxad_chan *chan = to_pxad_chan(dchan);
1069
1070 if (!dchan)
1071 return -EINVAL;
1072
1073 chan->cfg = *cfg;
1074 return 0;
1075}
1076
1077static int pxad_terminate_all(struct dma_chan *dchan)
1078{
1079 struct pxad_chan *chan = to_pxad_chan(dchan);
1080 struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
1081 struct virt_dma_desc *vd = NULL;
1082 unsigned long flags;
1083 struct pxad_phy *phy;
1084 LIST_HEAD(head);
1085
1086 dev_dbg(&chan->vc.chan.dev->device,
1087 "%s(): vchan %p: terminate all\n", __func__, &chan->vc);
1088
1089 spin_lock_irqsave(&chan->vc.lock, flags);
1090 vchan_get_all_descriptors(vc: &chan->vc, head: &head);
1091
1092 list_for_each_entry(vd, &head, node) {
1093 dev_dbg(&chan->vc.chan.dev->device,
1094 "%s(): cancelling txd %p[%x] (completed=%d)", __func__,
1095 vd, vd->tx.cookie, is_desc_completed(vd));
1096 }
1097
1098 phy = chan->phy;
1099 if (phy) {
1100 phy_disable(phy: chan->phy);
1101 pxad_free_phy(chan);
1102 chan->phy = NULL;
1103 spin_lock(lock: &pdev->phy_lock);
1104 phy->vchan = NULL;
1105 spin_unlock(lock: &pdev->phy_lock);
1106 }
1107 spin_unlock_irqrestore(lock: &chan->vc.lock, flags);
1108 vchan_dma_desc_free_list(vc: &chan->vc, head: &head);
1109
1110 return 0;
1111}
1112
1113static unsigned int pxad_residue(struct pxad_chan *chan,
1114 dma_cookie_t cookie)
1115{
1116 struct virt_dma_desc *vd = NULL;
1117 struct pxad_desc_sw *sw_desc = NULL;
1118 struct pxad_desc_hw *hw_desc = NULL;
1119 u32 curr, start, len, end, residue = 0;
1120 unsigned long flags;
1121 bool passed = false;
1122 int i;
1123
1124 /*
1125 * If the channel does not have a phy pointer anymore, it has already
1126 * been completed. Therefore, its residue is 0.
1127 */
1128 if (!chan->phy)
1129 return 0;
1130
1131 spin_lock_irqsave(&chan->vc.lock, flags);
1132
1133 vd = vchan_find_desc(&chan->vc, cookie);
1134 if (!vd)
1135 goto out;
1136
1137 sw_desc = to_pxad_sw_desc(vd);
1138 if (sw_desc->hw_desc[0]->dcmd & PXA_DCMD_INCSRCADDR)
1139 curr = phy_readl_relaxed(chan->phy, DSADR);
1140 else
1141 curr = phy_readl_relaxed(chan->phy, DTADR);
1142
1143 /*
1144 * curr has to be actually read before checking descriptor
1145 * completion, so that a curr inside a status updater
1146 * descriptor implies the following test returns true, and
1147 * preventing reordering of curr load and the test.
1148 */
1149 rmb();
1150 if (is_desc_completed(vd))
1151 goto out;
1152
1153 for (i = 0; i < sw_desc->nb_desc - 1; i++) {
1154 hw_desc = sw_desc->hw_desc[i];
1155 if (sw_desc->hw_desc[0]->dcmd & PXA_DCMD_INCSRCADDR)
1156 start = hw_desc->dsadr;
1157 else
1158 start = hw_desc->dtadr;
1159 len = hw_desc->dcmd & PXA_DCMD_LENGTH;
1160 end = start + len;
1161
1162 /*
1163 * 'passed' will be latched once we found the descriptor
1164 * which lies inside the boundaries of the curr
1165 * pointer. All descriptors that occur in the list
1166 * _after_ we found that partially handled descriptor
1167 * are still to be processed and are hence added to the
1168 * residual bytes counter.
1169 */
1170
1171 if (passed) {
1172 residue += len;
1173 } else if (curr >= start && curr <= end) {
1174 residue += end - curr;
1175 passed = true;
1176 }
1177 }
1178 if (!passed)
1179 residue = sw_desc->len;
1180
1181out:
1182 spin_unlock_irqrestore(lock: &chan->vc.lock, flags);
1183 dev_dbg(&chan->vc.chan.dev->device,
1184 "%s(): txd %p[%x] sw_desc=%p: %d\n",
1185 __func__, vd, cookie, sw_desc, residue);
1186 return residue;
1187}
1188
1189static enum dma_status pxad_tx_status(struct dma_chan *dchan,
1190 dma_cookie_t cookie,
1191 struct dma_tx_state *txstate)
1192{
1193 struct pxad_chan *chan = to_pxad_chan(dchan);
1194 enum dma_status ret;
1195
1196 if (cookie == chan->bus_error)
1197 return DMA_ERROR;
1198
1199 ret = dma_cookie_status(chan: dchan, cookie, state: txstate);
1200 if (likely(txstate && (ret != DMA_ERROR)))
1201 dma_set_residue(state: txstate, residue: pxad_residue(chan, cookie));
1202
1203 return ret;
1204}
1205
1206static void pxad_synchronize(struct dma_chan *dchan)
1207{
1208 struct pxad_chan *chan = to_pxad_chan(dchan);
1209
1210 wait_event(chan->wq_state, !is_chan_running(chan));
1211 vchan_synchronize(vc: &chan->vc);
1212}
1213
1214static void pxad_free_channels(struct dma_device *dmadev)
1215{
1216 struct pxad_chan *c, *cn;
1217
1218 list_for_each_entry_safe(c, cn, &dmadev->channels,
1219 vc.chan.device_node) {
1220 list_del(entry: &c->vc.chan.device_node);
1221 tasklet_kill(t: &c->vc.task);
1222 }
1223}
1224
1225static void pxad_remove(struct platform_device *op)
1226{
1227 struct pxad_device *pdev = platform_get_drvdata(pdev: op);
1228
1229 pxad_cleanup_debugfs(pdev);
1230 pxad_free_channels(dmadev: &pdev->slave);
1231}
1232
1233static int pxad_init_phys(struct platform_device *op,
1234 struct pxad_device *pdev,
1235 unsigned int nb_phy_chans)
1236{
1237 int irq0, irq, nr_irq = 0, i, ret;
1238 struct pxad_phy *phy;
1239
1240 irq0 = platform_get_irq(op, 0);
1241 if (irq0 < 0)
1242 return irq0;
1243
1244 pdev->phys = devm_kcalloc(dev: &op->dev, n: nb_phy_chans,
1245 size: sizeof(pdev->phys[0]), GFP_KERNEL);
1246 if (!pdev->phys)
1247 return -ENOMEM;
1248
1249 for (i = 0; i < nb_phy_chans; i++)
1250 if (platform_get_irq_optional(op, i) > 0)
1251 nr_irq++;
1252
1253 for (i = 0; i < nb_phy_chans; i++) {
1254 phy = &pdev->phys[i];
1255 phy->base = pdev->base;
1256 phy->idx = i;
1257 irq = platform_get_irq_optional(op, i);
1258 if ((nr_irq > 1) && (irq > 0))
1259 ret = devm_request_irq(dev: &op->dev, irq,
1260 handler: pxad_chan_handler,
1261 IRQF_SHARED, devname: "pxa-dma", dev_id: phy);
1262 if ((nr_irq == 1) && (i == 0))
1263 ret = devm_request_irq(dev: &op->dev, irq: irq0,
1264 handler: pxad_int_handler,
1265 IRQF_SHARED, devname: "pxa-dma", dev_id: pdev);
1266 if (ret) {
1267 dev_err(pdev->slave.dev,
1268 "%s(): can't request irq %d:%d\n", __func__,
1269 irq, ret);
1270 return ret;
1271 }
1272 }
1273
1274 return 0;
1275}
1276
1277static const struct of_device_id pxad_dt_ids[] = {
1278 { .compatible = "marvell,pdma-1.0", },
1279 {}
1280};
1281MODULE_DEVICE_TABLE(of, pxad_dt_ids);
1282
1283static struct dma_chan *pxad_dma_xlate(struct of_phandle_args *dma_spec,
1284 struct of_dma *ofdma)
1285{
1286 struct pxad_device *d = ofdma->of_dma_data;
1287 struct dma_chan *chan;
1288
1289 chan = dma_get_any_slave_channel(device: &d->slave);
1290 if (!chan)
1291 return NULL;
1292
1293 to_pxad_chan(chan)->drcmr = dma_spec->args[0];
1294 to_pxad_chan(chan)->prio = dma_spec->args[1];
1295
1296 return chan;
1297}
1298
1299static int pxad_init_dmadev(struct platform_device *op,
1300 struct pxad_device *pdev,
1301 unsigned int nr_phy_chans,
1302 unsigned int nr_requestors)
1303{
1304 int ret;
1305 unsigned int i;
1306 struct pxad_chan *c;
1307
1308 pdev->nr_chans = nr_phy_chans;
1309 pdev->nr_requestors = nr_requestors;
1310 INIT_LIST_HEAD(list: &pdev->slave.channels);
1311 pdev->slave.device_alloc_chan_resources = pxad_alloc_chan_resources;
1312 pdev->slave.device_free_chan_resources = pxad_free_chan_resources;
1313 pdev->slave.device_tx_status = pxad_tx_status;
1314 pdev->slave.device_issue_pending = pxad_issue_pending;
1315 pdev->slave.device_config = pxad_config;
1316 pdev->slave.device_synchronize = pxad_synchronize;
1317 pdev->slave.device_terminate_all = pxad_terminate_all;
1318
1319 if (op->dev.coherent_dma_mask)
1320 dma_set_mask(dev: &op->dev, mask: op->dev.coherent_dma_mask);
1321 else
1322 dma_set_mask(dev: &op->dev, DMA_BIT_MASK(32));
1323
1324 ret = pxad_init_phys(op, pdev, nb_phy_chans: nr_phy_chans);
1325 if (ret)
1326 return ret;
1327
1328 for (i = 0; i < nr_phy_chans; i++) {
1329 c = devm_kzalloc(dev: &op->dev, size: sizeof(*c), GFP_KERNEL);
1330 if (!c)
1331 return -ENOMEM;
1332
1333 c->drcmr = U32_MAX;
1334 c->prio = PXAD_PRIO_LOWEST;
1335 c->vc.desc_free = pxad_free_desc;
1336 vchan_init(vc: &c->vc, dmadev: &pdev->slave);
1337 init_waitqueue_head(&c->wq_state);
1338 }
1339
1340 return dmaenginem_async_device_register(device: &pdev->slave);
1341}
1342
1343static int pxad_probe(struct platform_device *op)
1344{
1345 struct pxad_device *pdev;
1346 const struct dma_slave_map *slave_map = NULL;
1347 struct mmp_dma_platdata *pdata = dev_get_platdata(dev: &op->dev);
1348 int ret, dma_channels = 0, nb_requestors = 0, slave_map_cnt = 0;
1349 const enum dma_slave_buswidth widths =
1350 DMA_SLAVE_BUSWIDTH_1_BYTE | DMA_SLAVE_BUSWIDTH_2_BYTES |
1351 DMA_SLAVE_BUSWIDTH_4_BYTES;
1352
1353 pdev = devm_kzalloc(dev: &op->dev, size: sizeof(*pdev), GFP_KERNEL);
1354 if (!pdev)
1355 return -ENOMEM;
1356
1357 spin_lock_init(&pdev->phy_lock);
1358
1359 pdev->base = devm_platform_ioremap_resource(pdev: op, index: 0);
1360 if (IS_ERR(ptr: pdev->base))
1361 return PTR_ERR(ptr: pdev->base);
1362
1363 if (op->dev.of_node) {
1364 /* Parse new and deprecated dma-channels properties */
1365 if (of_property_read_u32(np: op->dev.of_node, propname: "dma-channels",
1366 out_value: &dma_channels))
1367 of_property_read_u32(np: op->dev.of_node, propname: "#dma-channels",
1368 out_value: &dma_channels);
1369 /* Parse new and deprecated dma-requests properties */
1370 ret = of_property_read_u32(np: op->dev.of_node, propname: "dma-requests",
1371 out_value: &nb_requestors);
1372 if (ret)
1373 ret = of_property_read_u32(np: op->dev.of_node, propname: "#dma-requests",
1374 out_value: &nb_requestors);
1375 if (ret) {
1376 dev_warn(pdev->slave.dev,
1377 "#dma-requests set to default 32 as missing in OF: %d",
1378 ret);
1379 nb_requestors = 32;
1380 }
1381 } else if (pdata && pdata->dma_channels) {
1382 dma_channels = pdata->dma_channels;
1383 nb_requestors = pdata->nb_requestors;
1384 slave_map = pdata->slave_map;
1385 slave_map_cnt = pdata->slave_map_cnt;
1386 } else {
1387 dma_channels = 32; /* default 32 channel */
1388 }
1389
1390 dma_cap_set(DMA_SLAVE, pdev->slave.cap_mask);
1391 dma_cap_set(DMA_MEMCPY, pdev->slave.cap_mask);
1392 dma_cap_set(DMA_CYCLIC, pdev->slave.cap_mask);
1393 dma_cap_set(DMA_PRIVATE, pdev->slave.cap_mask);
1394 pdev->slave.device_prep_dma_memcpy = pxad_prep_memcpy;
1395 pdev->slave.device_prep_slave_sg = pxad_prep_slave_sg;
1396 pdev->slave.device_prep_dma_cyclic = pxad_prep_dma_cyclic;
1397 pdev->slave.filter.map = slave_map;
1398 pdev->slave.filter.mapcnt = slave_map_cnt;
1399 pdev->slave.filter.fn = pxad_filter_fn;
1400
1401 pdev->slave.copy_align = PDMA_ALIGNMENT;
1402 pdev->slave.src_addr_widths = widths;
1403 pdev->slave.dst_addr_widths = widths;
1404 pdev->slave.directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
1405 pdev->slave.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
1406 pdev->slave.descriptor_reuse = true;
1407
1408 pdev->slave.dev = &op->dev;
1409 ret = pxad_init_dmadev(op, pdev, nr_phy_chans: dma_channels, nr_requestors: nb_requestors);
1410 if (ret) {
1411 dev_err(pdev->slave.dev, "unable to register\n");
1412 return ret;
1413 }
1414
1415 if (op->dev.of_node) {
1416 /* Device-tree DMA controller registration */
1417 ret = of_dma_controller_register(np: op->dev.of_node,
1418 of_dma_xlate: pxad_dma_xlate, data: pdev);
1419 if (ret < 0) {
1420 dev_err(pdev->slave.dev,
1421 "of_dma_controller_register failed\n");
1422 return ret;
1423 }
1424 }
1425
1426 platform_set_drvdata(pdev: op, data: pdev);
1427 pxad_init_debugfs(pdev);
1428 dev_info(pdev->slave.dev, "initialized %d channels on %d requestors\n",
1429 dma_channels, nb_requestors);
1430 return 0;
1431}
1432
1433static const struct platform_device_id pxad_id_table[] = {
1434 { "pxa-dma", },
1435 { },
1436};
1437
1438static struct platform_driver pxad_driver = {
1439 .driver = {
1440 .name = "pxa-dma",
1441 .of_match_table = pxad_dt_ids,
1442 },
1443 .id_table = pxad_id_table,
1444 .probe = pxad_probe,
1445 .remove_new = pxad_remove,
1446};
1447
1448static bool pxad_filter_fn(struct dma_chan *chan, void *param)
1449{
1450 struct pxad_chan *c = to_pxad_chan(chan);
1451 struct pxad_param *p = param;
1452
1453 if (chan->device->dev->driver != &pxad_driver.driver)
1454 return false;
1455
1456 c->drcmr = p->drcmr;
1457 c->prio = p->prio;
1458
1459 return true;
1460}
1461
1462module_platform_driver(pxad_driver);
1463
1464MODULE_DESCRIPTION("Marvell PXA Peripheral DMA Driver");
1465MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
1466MODULE_LICENSE("GPL v2");
1467

source code of linux/drivers/dma/pxa_dma.c