GNU Linux-libre 4.9.328-gnu1
[releases.git] / drivers / dma / pxa_dma.c
1 /*
2  * Copyright 2015 Robert Jarzmik <robert.jarzmik@free.fr>
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8
9 #include <linux/err.h>
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/types.h>
13 #include <linux/interrupt.h>
14 #include <linux/dma-mapping.h>
15 #include <linux/slab.h>
16 #include <linux/dmaengine.h>
17 #include <linux/platform_device.h>
18 #include <linux/device.h>
19 #include <linux/platform_data/mmp_dma.h>
20 #include <linux/dmapool.h>
21 #include <linux/of_device.h>
22 #include <linux/of_dma.h>
23 #include <linux/of.h>
24 #include <linux/wait.h>
25 #include <linux/dma/pxa-dma.h>
26
27 #include "dmaengine.h"
28 #include "virt-dma.h"
29
30 #define DCSR(n)         (0x0000 + ((n) << 2))
31 #define DALGN(n)        0x00a0
32 #define DINT            0x00f0
33 #define DDADR(n)        (0x0200 + ((n) << 4))
34 #define DSADR(n)        (0x0204 + ((n) << 4))
35 #define DTADR(n)        (0x0208 + ((n) << 4))
36 #define DCMD(n)         (0x020c + ((n) << 4))
37
38 #define PXA_DCSR_RUN            BIT(31) /* Run Bit (read / write) */
39 #define PXA_DCSR_NODESC         BIT(30) /* No-Descriptor Fetch (read / write) */
40 #define PXA_DCSR_STOPIRQEN      BIT(29) /* Stop Interrupt Enable (R/W) */
41 #define PXA_DCSR_REQPEND        BIT(8)  /* Request Pending (read-only) */
42 #define PXA_DCSR_STOPSTATE      BIT(3)  /* Stop State (read-only) */
43 #define PXA_DCSR_ENDINTR        BIT(2)  /* End Interrupt (read / write) */
44 #define PXA_DCSR_STARTINTR      BIT(1)  /* Start Interrupt (read / write) */
45 #define PXA_DCSR_BUSERR         BIT(0)  /* Bus Error Interrupt (read / write) */
46
47 #define PXA_DCSR_EORIRQEN       BIT(28) /* End of Receive IRQ Enable (R/W) */
48 #define PXA_DCSR_EORJMPEN       BIT(27) /* Jump to next descriptor on EOR */
49 #define PXA_DCSR_EORSTOPEN      BIT(26) /* STOP on an EOR */
50 #define PXA_DCSR_SETCMPST       BIT(25) /* Set Descriptor Compare Status */
51 #define PXA_DCSR_CLRCMPST       BIT(24) /* Clear Descriptor Compare Status */
52 #define PXA_DCSR_CMPST          BIT(10) /* The Descriptor Compare Status */
53 #define PXA_DCSR_EORINTR        BIT(9)  /* The end of Receive */
54
55 #define DRCMR_MAPVLD    BIT(7)  /* Map Valid (read / write) */
56 #define DRCMR_CHLNUM    0x1f    /* mask for Channel Number (read / write) */
57
58 #define DDADR_DESCADDR  0xfffffff0      /* Address of next descriptor (mask) */
59 #define DDADR_STOP      BIT(0)  /* Stop (read / write) */
60
61 #define PXA_DCMD_INCSRCADDR     BIT(31) /* Source Address Increment Setting. */
62 #define PXA_DCMD_INCTRGADDR     BIT(30) /* Target Address Increment Setting. */
63 #define PXA_DCMD_FLOWSRC        BIT(29) /* Flow Control by the source. */
64 #define PXA_DCMD_FLOWTRG        BIT(28) /* Flow Control by the target. */
65 #define PXA_DCMD_STARTIRQEN     BIT(22) /* Start Interrupt Enable */
66 #define PXA_DCMD_ENDIRQEN       BIT(21) /* End Interrupt Enable */
67 #define PXA_DCMD_ENDIAN         BIT(18) /* Device Endian-ness. */
68 #define PXA_DCMD_BURST8         (1 << 16)       /* 8 byte burst */
69 #define PXA_DCMD_BURST16        (2 << 16)       /* 16 byte burst */
70 #define PXA_DCMD_BURST32        (3 << 16)       /* 32 byte burst */
71 #define PXA_DCMD_WIDTH1         (1 << 14)       /* 1 byte width */
72 #define PXA_DCMD_WIDTH2         (2 << 14)       /* 2 byte width (HalfWord) */
73 #define PXA_DCMD_WIDTH4         (3 << 14)       /* 4 byte width (Word) */
74 #define PXA_DCMD_LENGTH         0x01fff         /* length mask (max = 8K - 1) */
75
76 #define PDMA_ALIGNMENT          3
77 #define PDMA_MAX_DESC_BYTES     (PXA_DCMD_LENGTH & ~((1 << PDMA_ALIGNMENT) - 1))
78
79 struct pxad_desc_hw {
80         u32 ddadr;      /* Points to the next descriptor + flags */
81         u32 dsadr;      /* DSADR value for the current transfer */
82         u32 dtadr;      /* DTADR value for the current transfer */
83         u32 dcmd;       /* DCMD value for the current transfer */
84 } __aligned(16);
85
86 struct pxad_desc_sw {
87         struct virt_dma_desc    vd;             /* Virtual descriptor */
88         int                     nb_desc;        /* Number of hw. descriptors */
89         size_t                  len;            /* Number of bytes xfered */
90         dma_addr_t              first;          /* First descriptor's addr */
91
92         /* At least one descriptor has an src/dst address not multiple of 8 */
93         bool                    misaligned;
94         bool                    cyclic;
95         struct dma_pool         *desc_pool;     /* Channel's used allocator */
96
97         struct pxad_desc_hw     *hw_desc[];     /* DMA coherent descriptors */
98 };
99
100 struct pxad_phy {
101         int                     idx;
102         void __iomem            *base;
103         struct pxad_chan        *vchan;
104 };
105
106 struct pxad_chan {
107         struct virt_dma_chan    vc;             /* Virtual channel */
108         u32                     drcmr;          /* Requestor of the channel */
109         enum pxad_chan_prio     prio;           /* Required priority of phy */
110         /*
111          * At least one desc_sw in submitted or issued transfers on this channel
112          * has one address such as: addr % 8 != 0. This implies the DALGN
113          * setting on the phy.
114          */
115         bool                    misaligned;
116         struct dma_slave_config cfg;            /* Runtime config */
117
118         /* protected by vc->lock */
119         struct pxad_phy         *phy;
120         struct dma_pool         *desc_pool;     /* Descriptors pool */
121         dma_cookie_t            bus_error;
122
123         wait_queue_head_t       wq_state;
124 };
125
126 struct pxad_device {
127         struct dma_device               slave;
128         int                             nr_chans;
129         int                             nr_requestors;
130         void __iomem                    *base;
131         struct pxad_phy                 *phys;
132         spinlock_t                      phy_lock;       /* Phy association */
133 #ifdef CONFIG_DEBUG_FS
134         struct dentry                   *dbgfs_root;
135         struct dentry                   *dbgfs_state;
136         struct dentry                   **dbgfs_chan;
137 #endif
138 };
139
140 #define tx_to_pxad_desc(tx)                                     \
141         container_of(tx, struct pxad_desc_sw, async_tx)
142 #define to_pxad_chan(dchan)                                     \
143         container_of(dchan, struct pxad_chan, vc.chan)
144 #define to_pxad_dev(dmadev)                                     \
145         container_of(dmadev, struct pxad_device, slave)
146 #define to_pxad_sw_desc(_vd)                            \
147         container_of((_vd), struct pxad_desc_sw, vd)
148
149 #define _phy_readl_relaxed(phy, _reg)                                   \
150         readl_relaxed((phy)->base + _reg((phy)->idx))
151 #define phy_readl_relaxed(phy, _reg)                                    \
152         ({                                                              \
153                 u32 _v;                                                 \
154                 _v = readl_relaxed((phy)->base + _reg((phy)->idx));     \
155                 dev_vdbg(&phy->vchan->vc.chan.dev->device,              \
156                          "%s(): readl(%s): 0x%08x\n", __func__, #_reg,  \
157                           _v);                                          \
158                 _v;                                                     \
159         })
160 #define phy_writel(phy, val, _reg)                                      \
161         do {                                                            \
162                 writel((val), (phy)->base + _reg((phy)->idx));          \
163                 dev_vdbg(&phy->vchan->vc.chan.dev->device,              \
164                          "%s(): writel(0x%08x, %s)\n",                  \
165                          __func__, (u32)(val), #_reg);                  \
166         } while (0)
167 #define phy_writel_relaxed(phy, val, _reg)                              \
168         do {                                                            \
169                 writel_relaxed((val), (phy)->base + _reg((phy)->idx));  \
170                 dev_vdbg(&phy->vchan->vc.chan.dev->device,              \
171                          "%s(): writel_relaxed(0x%08x, %s)\n",          \
172                          __func__, (u32)(val), #_reg);                  \
173         } while (0)
174
175 static unsigned int pxad_drcmr(unsigned int line)
176 {
177         if (line < 64)
178                 return 0x100 + line * 4;
179         return 0x1000 + line * 4;
180 }
181
182 /*
183  * Debug fs
184  */
185 #ifdef CONFIG_DEBUG_FS
186 #include <linux/debugfs.h>
187 #include <linux/uaccess.h>
188 #include <linux/seq_file.h>
189
190 static int dbg_show_requester_chan(struct seq_file *s, void *p)
191 {
192         struct pxad_phy *phy = s->private;
193         int i;
194         u32 drcmr;
195
196         seq_printf(s, "DMA channel %d requester :\n", phy->idx);
197         for (i = 0; i < 70; i++) {
198                 drcmr = readl_relaxed(phy->base + pxad_drcmr(i));
199                 if ((drcmr & DRCMR_CHLNUM) == phy->idx)
200                         seq_printf(s, "\tRequester %d (MAPVLD=%d)\n", i,
201                                    !!(drcmr & DRCMR_MAPVLD));
202         }
203         return 0;
204 }
205
206 static inline int dbg_burst_from_dcmd(u32 dcmd)
207 {
208         int burst = (dcmd >> 16) & 0x3;
209
210         return burst ? 4 << burst : 0;
211 }
212
213 static int is_phys_valid(unsigned long addr)
214 {
215         return pfn_valid(__phys_to_pfn(addr));
216 }
217
218 #define PXA_DCSR_STR(flag) (dcsr & PXA_DCSR_##flag ? #flag" " : "")
219 #define PXA_DCMD_STR(flag) (dcmd & PXA_DCMD_##flag ? #flag" " : "")
220
221 static int dbg_show_descriptors(struct seq_file *s, void *p)
222 {
223         struct pxad_phy *phy = s->private;
224         int i, max_show = 20, burst, width;
225         u32 dcmd;
226         unsigned long phys_desc, ddadr;
227         struct pxad_desc_hw *desc;
228
229         phys_desc = ddadr = _phy_readl_relaxed(phy, DDADR);
230
231         seq_printf(s, "DMA channel %d descriptors :\n", phy->idx);
232         seq_printf(s, "[%03d] First descriptor unknown\n", 0);
233         for (i = 1; i < max_show && is_phys_valid(phys_desc); i++) {
234                 desc = phys_to_virt(phys_desc);
235                 dcmd = desc->dcmd;
236                 burst = dbg_burst_from_dcmd(dcmd);
237                 width = (1 << ((dcmd >> 14) & 0x3)) >> 1;
238
239                 seq_printf(s, "[%03d] Desc at %08lx(virt %p)\n",
240                            i, phys_desc, desc);
241                 seq_printf(s, "\tDDADR = %08x\n", desc->ddadr);
242                 seq_printf(s, "\tDSADR = %08x\n", desc->dsadr);
243                 seq_printf(s, "\tDTADR = %08x\n", desc->dtadr);
244                 seq_printf(s, "\tDCMD  = %08x (%s%s%s%s%s%s%sburst=%d width=%d len=%d)\n",
245                            dcmd,
246                            PXA_DCMD_STR(INCSRCADDR), PXA_DCMD_STR(INCTRGADDR),
247                            PXA_DCMD_STR(FLOWSRC), PXA_DCMD_STR(FLOWTRG),
248                            PXA_DCMD_STR(STARTIRQEN), PXA_DCMD_STR(ENDIRQEN),
249                            PXA_DCMD_STR(ENDIAN), burst, width,
250                            dcmd & PXA_DCMD_LENGTH);
251                 phys_desc = desc->ddadr;
252         }
253         if (i == max_show)
254                 seq_printf(s, "[%03d] Desc at %08lx ... max display reached\n",
255                            i, phys_desc);
256         else
257                 seq_printf(s, "[%03d] Desc at %08lx is %s\n",
258                            i, phys_desc, phys_desc == DDADR_STOP ?
259                            "DDADR_STOP" : "invalid");
260
261         return 0;
262 }
263
264 static int dbg_show_chan_state(struct seq_file *s, void *p)
265 {
266         struct pxad_phy *phy = s->private;
267         u32 dcsr, dcmd;
268         int burst, width;
269         static const char * const str_prio[] = {
270                 "high", "normal", "low", "invalid"
271         };
272
273         dcsr = _phy_readl_relaxed(phy, DCSR);
274         dcmd = _phy_readl_relaxed(phy, DCMD);
275         burst = dbg_burst_from_dcmd(dcmd);
276         width = (1 << ((dcmd >> 14) & 0x3)) >> 1;
277
278         seq_printf(s, "DMA channel %d\n", phy->idx);
279         seq_printf(s, "\tPriority : %s\n",
280                           str_prio[(phy->idx & 0xf) / 4]);
281         seq_printf(s, "\tUnaligned transfer bit: %s\n",
282                           _phy_readl_relaxed(phy, DALGN) & BIT(phy->idx) ?
283                           "yes" : "no");
284         seq_printf(s, "\tDCSR  = %08x (%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s)\n",
285                    dcsr, PXA_DCSR_STR(RUN), PXA_DCSR_STR(NODESC),
286                    PXA_DCSR_STR(STOPIRQEN), PXA_DCSR_STR(EORIRQEN),
287                    PXA_DCSR_STR(EORJMPEN), PXA_DCSR_STR(EORSTOPEN),
288                    PXA_DCSR_STR(SETCMPST), PXA_DCSR_STR(CLRCMPST),
289                    PXA_DCSR_STR(CMPST), PXA_DCSR_STR(EORINTR),
290                    PXA_DCSR_STR(REQPEND), PXA_DCSR_STR(STOPSTATE),
291                    PXA_DCSR_STR(ENDINTR), PXA_DCSR_STR(STARTINTR),
292                    PXA_DCSR_STR(BUSERR));
293
294         seq_printf(s, "\tDCMD  = %08x (%s%s%s%s%s%s%sburst=%d width=%d len=%d)\n",
295                    dcmd,
296                    PXA_DCMD_STR(INCSRCADDR), PXA_DCMD_STR(INCTRGADDR),
297                    PXA_DCMD_STR(FLOWSRC), PXA_DCMD_STR(FLOWTRG),
298                    PXA_DCMD_STR(STARTIRQEN), PXA_DCMD_STR(ENDIRQEN),
299                    PXA_DCMD_STR(ENDIAN), burst, width, dcmd & PXA_DCMD_LENGTH);
300         seq_printf(s, "\tDSADR = %08x\n", _phy_readl_relaxed(phy, DSADR));
301         seq_printf(s, "\tDTADR = %08x\n", _phy_readl_relaxed(phy, DTADR));
302         seq_printf(s, "\tDDADR = %08x\n", _phy_readl_relaxed(phy, DDADR));
303
304         return 0;
305 }
306
307 static int dbg_show_state(struct seq_file *s, void *p)
308 {
309         struct pxad_device *pdev = s->private;
310
311         /* basic device status */
312         seq_puts(s, "DMA engine status\n");
313         seq_printf(s, "\tChannel number: %d\n", pdev->nr_chans);
314
315         return 0;
316 }
317
318 #define DBGFS_FUNC_DECL(name) \
319 static int dbg_open_##name(struct inode *inode, struct file *file) \
320 { \
321         return single_open(file, dbg_show_##name, inode->i_private); \
322 } \
323 static const struct file_operations dbg_fops_##name = { \
324         .open           = dbg_open_##name, \
325         .llseek         = seq_lseek, \
326         .read           = seq_read, \
327         .release        = single_release, \
328 }
329
330 DBGFS_FUNC_DECL(state);
331 DBGFS_FUNC_DECL(chan_state);
332 DBGFS_FUNC_DECL(descriptors);
333 DBGFS_FUNC_DECL(requester_chan);
334
335 static struct dentry *pxad_dbg_alloc_chan(struct pxad_device *pdev,
336                                              int ch, struct dentry *chandir)
337 {
338         char chan_name[11];
339         struct dentry *chan, *chan_state = NULL, *chan_descr = NULL;
340         struct dentry *chan_reqs = NULL;
341         void *dt;
342
343         scnprintf(chan_name, sizeof(chan_name), "%d", ch);
344         chan = debugfs_create_dir(chan_name, chandir);
345         dt = (void *)&pdev->phys[ch];
346
347         if (chan)
348                 chan_state = debugfs_create_file("state", 0400, chan, dt,
349                                                  &dbg_fops_chan_state);
350         if (chan_state)
351                 chan_descr = debugfs_create_file("descriptors", 0400, chan, dt,
352                                                  &dbg_fops_descriptors);
353         if (chan_descr)
354                 chan_reqs = debugfs_create_file("requesters", 0400, chan, dt,
355                                                 &dbg_fops_requester_chan);
356         if (!chan_reqs)
357                 goto err_state;
358
359         return chan;
360
361 err_state:
362         debugfs_remove_recursive(chan);
363         return NULL;
364 }
365
366 static void pxad_init_debugfs(struct pxad_device *pdev)
367 {
368         int i;
369         struct dentry *chandir;
370
371         pdev->dbgfs_root = debugfs_create_dir(dev_name(pdev->slave.dev), NULL);
372         if (IS_ERR(pdev->dbgfs_root) || !pdev->dbgfs_root)
373                 goto err_root;
374
375         pdev->dbgfs_state = debugfs_create_file("state", 0400, pdev->dbgfs_root,
376                                                 pdev, &dbg_fops_state);
377         if (!pdev->dbgfs_state)
378                 goto err_state;
379
380         pdev->dbgfs_chan =
381                 kmalloc_array(pdev->nr_chans, sizeof(*pdev->dbgfs_state),
382                               GFP_KERNEL);
383         if (!pdev->dbgfs_chan)
384                 goto err_alloc;
385
386         chandir = debugfs_create_dir("channels", pdev->dbgfs_root);
387         if (!chandir)
388                 goto err_chandir;
389
390         for (i = 0; i < pdev->nr_chans; i++) {
391                 pdev->dbgfs_chan[i] = pxad_dbg_alloc_chan(pdev, i, chandir);
392                 if (!pdev->dbgfs_chan[i])
393                         goto err_chans;
394         }
395
396         return;
397 err_chans:
398 err_chandir:
399         kfree(pdev->dbgfs_chan);
400 err_alloc:
401 err_state:
402         debugfs_remove_recursive(pdev->dbgfs_root);
403 err_root:
404         pr_err("pxad: debugfs is not available\n");
405 }
406
407 static void pxad_cleanup_debugfs(struct pxad_device *pdev)
408 {
409         debugfs_remove_recursive(pdev->dbgfs_root);
410 }
411 #else
412 static inline void pxad_init_debugfs(struct pxad_device *pdev) {}
413 static inline void pxad_cleanup_debugfs(struct pxad_device *pdev) {}
414 #endif
415
416 /*
417  * In the transition phase where legacy pxa handling is done at the same time as
418  * mmp_dma, the DMA physical channel split between the 2 DMA providers is done
419  * through legacy_reserved. Legacy code reserves DMA channels by settings
420  * corresponding bits in legacy_reserved.
421  */
422 static u32 legacy_reserved;
423 static u32 legacy_unavailable;
424
425 static struct pxad_phy *lookup_phy(struct pxad_chan *pchan)
426 {
427         int prio, i;
428         struct pxad_device *pdev = to_pxad_dev(pchan->vc.chan.device);
429         struct pxad_phy *phy, *found = NULL;
430         unsigned long flags;
431
432         /*
433          * dma channel priorities
434          * ch 0 - 3,  16 - 19  <--> (0)
435          * ch 4 - 7,  20 - 23  <--> (1)
436          * ch 8 - 11, 24 - 27  <--> (2)
437          * ch 12 - 15, 28 - 31  <--> (3)
438          */
439
440         spin_lock_irqsave(&pdev->phy_lock, flags);
441         for (prio = pchan->prio; prio >= PXAD_PRIO_HIGHEST; prio--) {
442                 for (i = 0; i < pdev->nr_chans; i++) {
443                         if (prio != (i & 0xf) >> 2)
444                                 continue;
445                         if ((i < 32) && (legacy_reserved & BIT(i)))
446                                 continue;
447                         phy = &pdev->phys[i];
448                         if (!phy->vchan) {
449                                 phy->vchan = pchan;
450                                 found = phy;
451                                 if (i < 32)
452                                         legacy_unavailable |= BIT(i);
453                                 goto out_unlock;
454                         }
455                 }
456         }
457
458 out_unlock:
459         spin_unlock_irqrestore(&pdev->phy_lock, flags);
460         dev_dbg(&pchan->vc.chan.dev->device,
461                 "%s(): phy=%p(%d)\n", __func__, found,
462                 found ? found->idx : -1);
463
464         return found;
465 }
466
467 static void pxad_free_phy(struct pxad_chan *chan)
468 {
469         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
470         unsigned long flags;
471         u32 reg;
472         int i;
473
474         dev_dbg(&chan->vc.chan.dev->device,
475                 "%s(): freeing\n", __func__);
476         if (!chan->phy)
477                 return;
478
479         /* clear the channel mapping in DRCMR */
480         if (chan->drcmr <= pdev->nr_requestors) {
481                 reg = pxad_drcmr(chan->drcmr);
482                 writel_relaxed(0, chan->phy->base + reg);
483         }
484
485         spin_lock_irqsave(&pdev->phy_lock, flags);
486         for (i = 0; i < 32; i++)
487                 if (chan->phy == &pdev->phys[i])
488                         legacy_unavailable &= ~BIT(i);
489         chan->phy->vchan = NULL;
490         chan->phy = NULL;
491         spin_unlock_irqrestore(&pdev->phy_lock, flags);
492 }
493
494 static bool is_chan_running(struct pxad_chan *chan)
495 {
496         u32 dcsr;
497         struct pxad_phy *phy = chan->phy;
498
499         if (!phy)
500                 return false;
501         dcsr = phy_readl_relaxed(phy, DCSR);
502         return dcsr & PXA_DCSR_RUN;
503 }
504
505 static bool is_running_chan_misaligned(struct pxad_chan *chan)
506 {
507         u32 dalgn;
508
509         BUG_ON(!chan->phy);
510         dalgn = phy_readl_relaxed(chan->phy, DALGN);
511         return dalgn & (BIT(chan->phy->idx));
512 }
513
514 static void phy_enable(struct pxad_phy *phy, bool misaligned)
515 {
516         struct pxad_device *pdev;
517         u32 reg, dalgn;
518
519         if (!phy->vchan)
520                 return;
521
522         dev_dbg(&phy->vchan->vc.chan.dev->device,
523                 "%s(); phy=%p(%d) misaligned=%d\n", __func__,
524                 phy, phy->idx, misaligned);
525
526         pdev = to_pxad_dev(phy->vchan->vc.chan.device);
527         if (phy->vchan->drcmr <= pdev->nr_requestors) {
528                 reg = pxad_drcmr(phy->vchan->drcmr);
529                 writel_relaxed(DRCMR_MAPVLD | phy->idx, phy->base + reg);
530         }
531
532         dalgn = phy_readl_relaxed(phy, DALGN);
533         if (misaligned)
534                 dalgn |= BIT(phy->idx);
535         else
536                 dalgn &= ~BIT(phy->idx);
537         phy_writel_relaxed(phy, dalgn, DALGN);
538
539         phy_writel(phy, PXA_DCSR_STOPIRQEN | PXA_DCSR_ENDINTR |
540                    PXA_DCSR_BUSERR | PXA_DCSR_RUN, DCSR);
541 }
542
543 static void phy_disable(struct pxad_phy *phy)
544 {
545         u32 dcsr;
546
547         if (!phy)
548                 return;
549
550         dcsr = phy_readl_relaxed(phy, DCSR);
551         dev_dbg(&phy->vchan->vc.chan.dev->device,
552                 "%s(): phy=%p(%d)\n", __func__, phy, phy->idx);
553         phy_writel(phy, dcsr & ~PXA_DCSR_RUN & ~PXA_DCSR_STOPIRQEN, DCSR);
554 }
555
556 static void pxad_launch_chan(struct pxad_chan *chan,
557                                  struct pxad_desc_sw *desc)
558 {
559         dev_dbg(&chan->vc.chan.dev->device,
560                 "%s(): desc=%p\n", __func__, desc);
561         if (!chan->phy) {
562                 chan->phy = lookup_phy(chan);
563                 if (!chan->phy) {
564                         dev_dbg(&chan->vc.chan.dev->device,
565                                 "%s(): no free dma channel\n", __func__);
566                         return;
567                 }
568         }
569         chan->bus_error = 0;
570
571         /*
572          * Program the descriptor's address into the DMA controller,
573          * then start the DMA transaction
574          */
575         phy_writel(chan->phy, desc->first, DDADR);
576         phy_enable(chan->phy, chan->misaligned);
577         wake_up(&chan->wq_state);
578 }
579
580 static void set_updater_desc(struct pxad_desc_sw *sw_desc,
581                              unsigned long flags)
582 {
583         struct pxad_desc_hw *updater =
584                 sw_desc->hw_desc[sw_desc->nb_desc - 1];
585         dma_addr_t dma = sw_desc->hw_desc[sw_desc->nb_desc - 2]->ddadr;
586
587         updater->ddadr = DDADR_STOP;
588         updater->dsadr = dma;
589         updater->dtadr = dma + 8;
590         updater->dcmd = PXA_DCMD_WIDTH4 | PXA_DCMD_BURST32 |
591                 (PXA_DCMD_LENGTH & sizeof(u32));
592         if (flags & DMA_PREP_INTERRUPT)
593                 updater->dcmd |= PXA_DCMD_ENDIRQEN;
594         if (sw_desc->cyclic)
595                 sw_desc->hw_desc[sw_desc->nb_desc - 2]->ddadr = sw_desc->first;
596 }
597
598 static bool is_desc_completed(struct virt_dma_desc *vd)
599 {
600         struct pxad_desc_sw *sw_desc = to_pxad_sw_desc(vd);
601         struct pxad_desc_hw *updater =
602                 sw_desc->hw_desc[sw_desc->nb_desc - 1];
603
604         return updater->dtadr != (updater->dsadr + 8);
605 }
606
607 static void pxad_desc_chain(struct virt_dma_desc *vd1,
608                                 struct virt_dma_desc *vd2)
609 {
610         struct pxad_desc_sw *desc1 = to_pxad_sw_desc(vd1);
611         struct pxad_desc_sw *desc2 = to_pxad_sw_desc(vd2);
612         dma_addr_t dma_to_chain;
613
614         dma_to_chain = desc2->first;
615         desc1->hw_desc[desc1->nb_desc - 1]->ddadr = dma_to_chain;
616 }
617
618 static bool pxad_try_hotchain(struct virt_dma_chan *vc,
619                                   struct virt_dma_desc *vd)
620 {
621         struct virt_dma_desc *vd_last_issued = NULL;
622         struct pxad_chan *chan = to_pxad_chan(&vc->chan);
623
624         /*
625          * Attempt to hot chain the tx if the phy is still running. This is
626          * considered successful only if either the channel is still running
627          * after the chaining, or if the chained transfer is completed after
628          * having been hot chained.
629          * A change of alignment is not allowed, and forbids hotchaining.
630          */
631         if (is_chan_running(chan)) {
632                 BUG_ON(list_empty(&vc->desc_issued));
633
634                 if (!is_running_chan_misaligned(chan) &&
635                     to_pxad_sw_desc(vd)->misaligned)
636                         return false;
637
638                 vd_last_issued = list_entry(vc->desc_issued.prev,
639                                             struct virt_dma_desc, node);
640                 pxad_desc_chain(vd_last_issued, vd);
641                 if (is_chan_running(chan) || is_desc_completed(vd))
642                         return true;
643         }
644
645         return false;
646 }
647
648 static unsigned int clear_chan_irq(struct pxad_phy *phy)
649 {
650         u32 dcsr;
651         u32 dint = readl(phy->base + DINT);
652
653         if (!(dint & BIT(phy->idx)))
654                 return PXA_DCSR_RUN;
655
656         /* clear irq */
657         dcsr = phy_readl_relaxed(phy, DCSR);
658         phy_writel(phy, dcsr, DCSR);
659         if ((dcsr & PXA_DCSR_BUSERR) && (phy->vchan))
660                 dev_warn(&phy->vchan->vc.chan.dev->device,
661                          "%s(chan=%p): PXA_DCSR_BUSERR\n",
662                          __func__, &phy->vchan);
663
664         return dcsr & ~PXA_DCSR_RUN;
665 }
666
667 static irqreturn_t pxad_chan_handler(int irq, void *dev_id)
668 {
669         struct pxad_phy *phy = dev_id;
670         struct pxad_chan *chan = phy->vchan;
671         struct virt_dma_desc *vd, *tmp;
672         unsigned int dcsr;
673         unsigned long flags;
674         bool vd_completed;
675         dma_cookie_t last_started = 0;
676
677         BUG_ON(!chan);
678
679         dcsr = clear_chan_irq(phy);
680         if (dcsr & PXA_DCSR_RUN)
681                 return IRQ_NONE;
682
683         spin_lock_irqsave(&chan->vc.lock, flags);
684         list_for_each_entry_safe(vd, tmp, &chan->vc.desc_issued, node) {
685                 vd_completed = is_desc_completed(vd);
686                 dev_dbg(&chan->vc.chan.dev->device,
687                         "%s(): checking txd %p[%x]: completed=%d dcsr=0x%x\n",
688                         __func__, vd, vd->tx.cookie, vd_completed,
689                         dcsr);
690                 last_started = vd->tx.cookie;
691                 if (to_pxad_sw_desc(vd)->cyclic) {
692                         vchan_cyclic_callback(vd);
693                         break;
694                 }
695                 if (vd_completed) {
696                         list_del(&vd->node);
697                         vchan_cookie_complete(vd);
698                 } else {
699                         break;
700                 }
701         }
702
703         if (dcsr & PXA_DCSR_BUSERR) {
704                 chan->bus_error = last_started;
705                 phy_disable(phy);
706         }
707
708         if (!chan->bus_error && dcsr & PXA_DCSR_STOPSTATE) {
709                 dev_dbg(&chan->vc.chan.dev->device,
710                 "%s(): channel stopped, submitted_empty=%d issued_empty=%d",
711                         __func__,
712                         list_empty(&chan->vc.desc_submitted),
713                         list_empty(&chan->vc.desc_issued));
714                 phy_writel_relaxed(phy, dcsr & ~PXA_DCSR_STOPIRQEN, DCSR);
715
716                 if (list_empty(&chan->vc.desc_issued)) {
717                         chan->misaligned =
718                                 !list_empty(&chan->vc.desc_submitted);
719                 } else {
720                         vd = list_first_entry(&chan->vc.desc_issued,
721                                               struct virt_dma_desc, node);
722                         pxad_launch_chan(chan, to_pxad_sw_desc(vd));
723                 }
724         }
725         spin_unlock_irqrestore(&chan->vc.lock, flags);
726         wake_up(&chan->wq_state);
727
728         return IRQ_HANDLED;
729 }
730
731 static irqreturn_t pxad_int_handler(int irq, void *dev_id)
732 {
733         struct pxad_device *pdev = dev_id;
734         struct pxad_phy *phy;
735         u32 dint = readl(pdev->base + DINT);
736         int i, ret = IRQ_NONE;
737
738         while (dint) {
739                 i = __ffs(dint);
740                 dint &= (dint - 1);
741                 phy = &pdev->phys[i];
742                 if ((i < 32) && (legacy_reserved & BIT(i)))
743                         continue;
744                 if (pxad_chan_handler(irq, phy) == IRQ_HANDLED)
745                         ret = IRQ_HANDLED;
746         }
747
748         return ret;
749 }
750
751 static int pxad_alloc_chan_resources(struct dma_chan *dchan)
752 {
753         struct pxad_chan *chan = to_pxad_chan(dchan);
754         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
755
756         if (chan->desc_pool)
757                 return 1;
758
759         chan->desc_pool = dma_pool_create(dma_chan_name(dchan),
760                                           pdev->slave.dev,
761                                           sizeof(struct pxad_desc_hw),
762                                           __alignof__(struct pxad_desc_hw),
763                                           0);
764         if (!chan->desc_pool) {
765                 dev_err(&chan->vc.chan.dev->device,
766                         "%s(): unable to allocate descriptor pool\n",
767                         __func__);
768                 return -ENOMEM;
769         }
770
771         return 1;
772 }
773
774 static void pxad_free_chan_resources(struct dma_chan *dchan)
775 {
776         struct pxad_chan *chan = to_pxad_chan(dchan);
777
778         vchan_free_chan_resources(&chan->vc);
779         dma_pool_destroy(chan->desc_pool);
780         chan->desc_pool = NULL;
781
782 }
783
784 static void pxad_free_desc(struct virt_dma_desc *vd)
785 {
786         int i;
787         dma_addr_t dma;
788         struct pxad_desc_sw *sw_desc = to_pxad_sw_desc(vd);
789
790         BUG_ON(sw_desc->nb_desc == 0);
791         for (i = sw_desc->nb_desc - 1; i >= 0; i--) {
792                 if (i > 0)
793                         dma = sw_desc->hw_desc[i - 1]->ddadr;
794                 else
795                         dma = sw_desc->first;
796                 dma_pool_free(sw_desc->desc_pool,
797                               sw_desc->hw_desc[i], dma);
798         }
799         sw_desc->nb_desc = 0;
800         kfree(sw_desc);
801 }
802
803 static struct pxad_desc_sw *
804 pxad_alloc_desc(struct pxad_chan *chan, unsigned int nb_hw_desc)
805 {
806         struct pxad_desc_sw *sw_desc;
807         dma_addr_t dma;
808         int i;
809
810         sw_desc = kzalloc(sizeof(*sw_desc) +
811                           nb_hw_desc * sizeof(struct pxad_desc_hw *),
812                           GFP_NOWAIT);
813         if (!sw_desc)
814                 return NULL;
815         sw_desc->desc_pool = chan->desc_pool;
816
817         for (i = 0; i < nb_hw_desc; i++) {
818                 sw_desc->hw_desc[i] = dma_pool_alloc(sw_desc->desc_pool,
819                                                      GFP_NOWAIT, &dma);
820                 if (!sw_desc->hw_desc[i]) {
821                         dev_err(&chan->vc.chan.dev->device,
822                                 "%s(): Couldn't allocate the %dth hw_desc from dma_pool %p\n",
823                                 __func__, i, sw_desc->desc_pool);
824                         goto err;
825                 }
826
827                 if (i == 0)
828                         sw_desc->first = dma;
829                 else
830                         sw_desc->hw_desc[i - 1]->ddadr = dma;
831                 sw_desc->nb_desc++;
832         }
833
834         return sw_desc;
835 err:
836         pxad_free_desc(&sw_desc->vd);
837         return NULL;
838 }
839
840 static dma_cookie_t pxad_tx_submit(struct dma_async_tx_descriptor *tx)
841 {
842         struct virt_dma_chan *vc = to_virt_chan(tx->chan);
843         struct pxad_chan *chan = to_pxad_chan(&vc->chan);
844         struct virt_dma_desc *vd_chained = NULL,
845                 *vd = container_of(tx, struct virt_dma_desc, tx);
846         dma_cookie_t cookie;
847         unsigned long flags;
848
849         set_updater_desc(to_pxad_sw_desc(vd), tx->flags);
850
851         spin_lock_irqsave(&vc->lock, flags);
852         cookie = dma_cookie_assign(tx);
853
854         if (list_empty(&vc->desc_submitted) && pxad_try_hotchain(vc, vd)) {
855                 list_move_tail(&vd->node, &vc->desc_issued);
856                 dev_dbg(&chan->vc.chan.dev->device,
857                         "%s(): txd %p[%x]: submitted (hot linked)\n",
858                         __func__, vd, cookie);
859                 goto out;
860         }
861
862         /*
863          * Fallback to placing the tx in the submitted queue
864          */
865         if (!list_empty(&vc->desc_submitted)) {
866                 vd_chained = list_entry(vc->desc_submitted.prev,
867                                         struct virt_dma_desc, node);
868                 /*
869                  * Only chain the descriptors if no new misalignment is
870                  * introduced. If a new misalignment is chained, let the channel
871                  * stop, and be relaunched in misalign mode from the irq
872                  * handler.
873                  */
874                 if (chan->misaligned || !to_pxad_sw_desc(vd)->misaligned)
875                         pxad_desc_chain(vd_chained, vd);
876                 else
877                         vd_chained = NULL;
878         }
879         dev_dbg(&chan->vc.chan.dev->device,
880                 "%s(): txd %p[%x]: submitted (%s linked)\n",
881                 __func__, vd, cookie, vd_chained ? "cold" : "not");
882         list_move_tail(&vd->node, &vc->desc_submitted);
883         chan->misaligned |= to_pxad_sw_desc(vd)->misaligned;
884
885 out:
886         spin_unlock_irqrestore(&vc->lock, flags);
887         return cookie;
888 }
889
890 static void pxad_issue_pending(struct dma_chan *dchan)
891 {
892         struct pxad_chan *chan = to_pxad_chan(dchan);
893         struct virt_dma_desc *vd_first;
894         unsigned long flags;
895
896         spin_lock_irqsave(&chan->vc.lock, flags);
897         if (list_empty(&chan->vc.desc_submitted))
898                 goto out;
899
900         vd_first = list_first_entry(&chan->vc.desc_submitted,
901                                     struct virt_dma_desc, node);
902         dev_dbg(&chan->vc.chan.dev->device,
903                 "%s(): txd %p[%x]", __func__, vd_first, vd_first->tx.cookie);
904
905         vchan_issue_pending(&chan->vc);
906         if (!pxad_try_hotchain(&chan->vc, vd_first))
907                 pxad_launch_chan(chan, to_pxad_sw_desc(vd_first));
908 out:
909         spin_unlock_irqrestore(&chan->vc.lock, flags);
910 }
911
912 static inline struct dma_async_tx_descriptor *
913 pxad_tx_prep(struct virt_dma_chan *vc, struct virt_dma_desc *vd,
914                  unsigned long tx_flags)
915 {
916         struct dma_async_tx_descriptor *tx;
917         struct pxad_chan *chan = container_of(vc, struct pxad_chan, vc);
918
919         INIT_LIST_HEAD(&vd->node);
920         tx = vchan_tx_prep(vc, vd, tx_flags);
921         tx->tx_submit = pxad_tx_submit;
922         dev_dbg(&chan->vc.chan.dev->device,
923                 "%s(): vc=%p txd=%p[%x] flags=0x%lx\n", __func__,
924                 vc, vd, vd->tx.cookie,
925                 tx_flags);
926
927         return tx;
928 }
929
930 static void pxad_get_config(struct pxad_chan *chan,
931                             enum dma_transfer_direction dir,
932                             u32 *dcmd, u32 *dev_src, u32 *dev_dst)
933 {
934         u32 maxburst = 0, dev_addr = 0;
935         enum dma_slave_buswidth width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
936         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
937
938         *dcmd = 0;
939         if (dir == DMA_DEV_TO_MEM) {
940                 maxburst = chan->cfg.src_maxburst;
941                 width = chan->cfg.src_addr_width;
942                 dev_addr = chan->cfg.src_addr;
943                 *dev_src = dev_addr;
944                 *dcmd |= PXA_DCMD_INCTRGADDR;
945                 if (chan->drcmr <= pdev->nr_requestors)
946                         *dcmd |= PXA_DCMD_FLOWSRC;
947         }
948         if (dir == DMA_MEM_TO_DEV) {
949                 maxburst = chan->cfg.dst_maxburst;
950                 width = chan->cfg.dst_addr_width;
951                 dev_addr = chan->cfg.dst_addr;
952                 *dev_dst = dev_addr;
953                 *dcmd |= PXA_DCMD_INCSRCADDR;
954                 if (chan->drcmr <= pdev->nr_requestors)
955                         *dcmd |= PXA_DCMD_FLOWTRG;
956         }
957         if (dir == DMA_MEM_TO_MEM)
958                 *dcmd |= PXA_DCMD_BURST32 | PXA_DCMD_INCTRGADDR |
959                         PXA_DCMD_INCSRCADDR;
960
961         dev_dbg(&chan->vc.chan.dev->device,
962                 "%s(): dev_addr=0x%x maxburst=%d width=%d  dir=%d\n",
963                 __func__, dev_addr, maxburst, width, dir);
964
965         if (width == DMA_SLAVE_BUSWIDTH_1_BYTE)
966                 *dcmd |= PXA_DCMD_WIDTH1;
967         else if (width == DMA_SLAVE_BUSWIDTH_2_BYTES)
968                 *dcmd |= PXA_DCMD_WIDTH2;
969         else if (width == DMA_SLAVE_BUSWIDTH_4_BYTES)
970                 *dcmd |= PXA_DCMD_WIDTH4;
971
972         if (maxburst == 8)
973                 *dcmd |= PXA_DCMD_BURST8;
974         else if (maxburst == 16)
975                 *dcmd |= PXA_DCMD_BURST16;
976         else if (maxburst == 32)
977                 *dcmd |= PXA_DCMD_BURST32;
978 }
979
980 static struct dma_async_tx_descriptor *
981 pxad_prep_memcpy(struct dma_chan *dchan,
982                  dma_addr_t dma_dst, dma_addr_t dma_src,
983                  size_t len, unsigned long flags)
984 {
985         struct pxad_chan *chan = to_pxad_chan(dchan);
986         struct pxad_desc_sw *sw_desc;
987         struct pxad_desc_hw *hw_desc;
988         u32 dcmd;
989         unsigned int i, nb_desc = 0;
990         size_t copy;
991
992         if (!dchan || !len)
993                 return NULL;
994
995         dev_dbg(&chan->vc.chan.dev->device,
996                 "%s(): dma_dst=0x%lx dma_src=0x%lx len=%zu flags=%lx\n",
997                 __func__, (unsigned long)dma_dst, (unsigned long)dma_src,
998                 len, flags);
999         pxad_get_config(chan, DMA_MEM_TO_MEM, &dcmd, NULL, NULL);
1000
1001         nb_desc = DIV_ROUND_UP(len, PDMA_MAX_DESC_BYTES);
1002         sw_desc = pxad_alloc_desc(chan, nb_desc + 1);
1003         if (!sw_desc)
1004                 return NULL;
1005         sw_desc->len = len;
1006
1007         if (!IS_ALIGNED(dma_src, 1 << PDMA_ALIGNMENT) ||
1008             !IS_ALIGNED(dma_dst, 1 << PDMA_ALIGNMENT))
1009                 sw_desc->misaligned = true;
1010
1011         i = 0;
1012         do {
1013                 hw_desc = sw_desc->hw_desc[i++];
1014                 copy = min_t(size_t, len, PDMA_MAX_DESC_BYTES);
1015                 hw_desc->dcmd = dcmd | (PXA_DCMD_LENGTH & copy);
1016                 hw_desc->dsadr = dma_src;
1017                 hw_desc->dtadr = dma_dst;
1018                 len -= copy;
1019                 dma_src += copy;
1020                 dma_dst += copy;
1021         } while (len);
1022         set_updater_desc(sw_desc, flags);
1023
1024         return pxad_tx_prep(&chan->vc, &sw_desc->vd, flags);
1025 }
1026
1027 static struct dma_async_tx_descriptor *
1028 pxad_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
1029                    unsigned int sg_len, enum dma_transfer_direction dir,
1030                    unsigned long flags, void *context)
1031 {
1032         struct pxad_chan *chan = to_pxad_chan(dchan);
1033         struct pxad_desc_sw *sw_desc;
1034         size_t len, avail;
1035         struct scatterlist *sg;
1036         dma_addr_t dma;
1037         u32 dcmd, dsadr = 0, dtadr = 0;
1038         unsigned int nb_desc = 0, i, j = 0;
1039
1040         if ((sgl == NULL) || (sg_len == 0))
1041                 return NULL;
1042
1043         pxad_get_config(chan, dir, &dcmd, &dsadr, &dtadr);
1044         dev_dbg(&chan->vc.chan.dev->device,
1045                 "%s(): dir=%d flags=%lx\n", __func__, dir, flags);
1046
1047         for_each_sg(sgl, sg, sg_len, i)
1048                 nb_desc += DIV_ROUND_UP(sg_dma_len(sg), PDMA_MAX_DESC_BYTES);
1049         sw_desc = pxad_alloc_desc(chan, nb_desc + 1);
1050         if (!sw_desc)
1051                 return NULL;
1052
1053         for_each_sg(sgl, sg, sg_len, i) {
1054                 dma = sg_dma_address(sg);
1055                 avail = sg_dma_len(sg);
1056                 sw_desc->len += avail;
1057
1058                 do {
1059                         len = min_t(size_t, avail, PDMA_MAX_DESC_BYTES);
1060                         if (dma & 0x7)
1061                                 sw_desc->misaligned = true;
1062
1063                         sw_desc->hw_desc[j]->dcmd =
1064                                 dcmd | (PXA_DCMD_LENGTH & len);
1065                         sw_desc->hw_desc[j]->dsadr = dsadr ? dsadr : dma;
1066                         sw_desc->hw_desc[j++]->dtadr = dtadr ? dtadr : dma;
1067
1068                         dma += len;
1069                         avail -= len;
1070                 } while (avail);
1071         }
1072         set_updater_desc(sw_desc, flags);
1073
1074         return pxad_tx_prep(&chan->vc, &sw_desc->vd, flags);
1075 }
1076
1077 static struct dma_async_tx_descriptor *
1078 pxad_prep_dma_cyclic(struct dma_chan *dchan,
1079                      dma_addr_t buf_addr, size_t len, size_t period_len,
1080                      enum dma_transfer_direction dir, unsigned long flags)
1081 {
1082         struct pxad_chan *chan = to_pxad_chan(dchan);
1083         struct pxad_desc_sw *sw_desc;
1084         struct pxad_desc_hw **phw_desc;
1085         dma_addr_t dma;
1086         u32 dcmd, dsadr = 0, dtadr = 0;
1087         unsigned int nb_desc = 0;
1088
1089         if (!dchan || !len || !period_len)
1090                 return NULL;
1091         if ((dir != DMA_DEV_TO_MEM) && (dir != DMA_MEM_TO_DEV)) {
1092                 dev_err(&chan->vc.chan.dev->device,
1093                         "Unsupported direction for cyclic DMA\n");
1094                 return NULL;
1095         }
1096         /* the buffer length must be a multiple of period_len */
1097         if (len % period_len != 0 || period_len > PDMA_MAX_DESC_BYTES ||
1098             !IS_ALIGNED(period_len, 1 << PDMA_ALIGNMENT))
1099                 return NULL;
1100
1101         pxad_get_config(chan, dir, &dcmd, &dsadr, &dtadr);
1102         dcmd |= PXA_DCMD_ENDIRQEN | (PXA_DCMD_LENGTH & period_len);
1103         dev_dbg(&chan->vc.chan.dev->device,
1104                 "%s(): buf_addr=0x%lx len=%zu period=%zu dir=%d flags=%lx\n",
1105                 __func__, (unsigned long)buf_addr, len, period_len, dir, flags);
1106
1107         nb_desc = DIV_ROUND_UP(period_len, PDMA_MAX_DESC_BYTES);
1108         nb_desc *= DIV_ROUND_UP(len, period_len);
1109         sw_desc = pxad_alloc_desc(chan, nb_desc + 1);
1110         if (!sw_desc)
1111                 return NULL;
1112         sw_desc->cyclic = true;
1113         sw_desc->len = len;
1114
1115         phw_desc = sw_desc->hw_desc;
1116         dma = buf_addr;
1117         do {
1118                 phw_desc[0]->dsadr = dsadr ? dsadr : dma;
1119                 phw_desc[0]->dtadr = dtadr ? dtadr : dma;
1120                 phw_desc[0]->dcmd = dcmd;
1121                 phw_desc++;
1122                 dma += period_len;
1123                 len -= period_len;
1124         } while (len);
1125         set_updater_desc(sw_desc, flags);
1126
1127         return pxad_tx_prep(&chan->vc, &sw_desc->vd, flags);
1128 }
1129
1130 static int pxad_config(struct dma_chan *dchan,
1131                        struct dma_slave_config *cfg)
1132 {
1133         struct pxad_chan *chan = to_pxad_chan(dchan);
1134
1135         if (!dchan)
1136                 return -EINVAL;
1137
1138         chan->cfg = *cfg;
1139         return 0;
1140 }
1141
1142 static int pxad_terminate_all(struct dma_chan *dchan)
1143 {
1144         struct pxad_chan *chan = to_pxad_chan(dchan);
1145         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
1146         struct virt_dma_desc *vd = NULL;
1147         unsigned long flags;
1148         struct pxad_phy *phy;
1149         LIST_HEAD(head);
1150
1151         dev_dbg(&chan->vc.chan.dev->device,
1152                 "%s(): vchan %p: terminate all\n", __func__, &chan->vc);
1153
1154         spin_lock_irqsave(&chan->vc.lock, flags);
1155         vchan_get_all_descriptors(&chan->vc, &head);
1156
1157         list_for_each_entry(vd, &head, node) {
1158                 dev_dbg(&chan->vc.chan.dev->device,
1159                         "%s(): cancelling txd %p[%x] (completed=%d)", __func__,
1160                         vd, vd->tx.cookie, is_desc_completed(vd));
1161         }
1162
1163         phy = chan->phy;
1164         if (phy) {
1165                 phy_disable(chan->phy);
1166                 pxad_free_phy(chan);
1167                 chan->phy = NULL;
1168                 spin_lock(&pdev->phy_lock);
1169                 phy->vchan = NULL;
1170                 spin_unlock(&pdev->phy_lock);
1171         }
1172         spin_unlock_irqrestore(&chan->vc.lock, flags);
1173         vchan_dma_desc_free_list(&chan->vc, &head);
1174
1175         return 0;
1176 }
1177
1178 static unsigned int pxad_residue(struct pxad_chan *chan,
1179                                  dma_cookie_t cookie)
1180 {
1181         struct virt_dma_desc *vd = NULL;
1182         struct pxad_desc_sw *sw_desc = NULL;
1183         struct pxad_desc_hw *hw_desc = NULL;
1184         u32 curr, start, len, end, residue = 0;
1185         unsigned long flags;
1186         bool passed = false;
1187         int i;
1188
1189         /*
1190          * If the channel does not have a phy pointer anymore, it has already
1191          * been completed. Therefore, its residue is 0.
1192          */
1193         if (!chan->phy)
1194                 return 0;
1195
1196         spin_lock_irqsave(&chan->vc.lock, flags);
1197
1198         vd = vchan_find_desc(&chan->vc, cookie);
1199         if (!vd)
1200                 goto out;
1201
1202         sw_desc = to_pxad_sw_desc(vd);
1203         if (sw_desc->hw_desc[0]->dcmd & PXA_DCMD_INCSRCADDR)
1204                 curr = phy_readl_relaxed(chan->phy, DSADR);
1205         else
1206                 curr = phy_readl_relaxed(chan->phy, DTADR);
1207
1208         /*
1209          * curr has to be actually read before checking descriptor
1210          * completion, so that a curr inside a status updater
1211          * descriptor implies the following test returns true, and
1212          * preventing reordering of curr load and the test.
1213          */
1214         rmb();
1215         if (is_desc_completed(vd))
1216                 goto out;
1217
1218         for (i = 0; i < sw_desc->nb_desc - 1; i++) {
1219                 hw_desc = sw_desc->hw_desc[i];
1220                 if (sw_desc->hw_desc[0]->dcmd & PXA_DCMD_INCSRCADDR)
1221                         start = hw_desc->dsadr;
1222                 else
1223                         start = hw_desc->dtadr;
1224                 len = hw_desc->dcmd & PXA_DCMD_LENGTH;
1225                 end = start + len;
1226
1227                 /*
1228                  * 'passed' will be latched once we found the descriptor
1229                  * which lies inside the boundaries of the curr
1230                  * pointer. All descriptors that occur in the list
1231                  * _after_ we found that partially handled descriptor
1232                  * are still to be processed and are hence added to the
1233                  * residual bytes counter.
1234                  */
1235
1236                 if (passed) {
1237                         residue += len;
1238                 } else if (curr >= start && curr <= end) {
1239                         residue += end - curr;
1240                         passed = true;
1241                 }
1242         }
1243         if (!passed)
1244                 residue = sw_desc->len;
1245
1246 out:
1247         spin_unlock_irqrestore(&chan->vc.lock, flags);
1248         dev_dbg(&chan->vc.chan.dev->device,
1249                 "%s(): txd %p[%x] sw_desc=%p: %d\n",
1250                 __func__, vd, cookie, sw_desc, residue);
1251         return residue;
1252 }
1253
1254 static enum dma_status pxad_tx_status(struct dma_chan *dchan,
1255                                       dma_cookie_t cookie,
1256                                       struct dma_tx_state *txstate)
1257 {
1258         struct pxad_chan *chan = to_pxad_chan(dchan);
1259         enum dma_status ret;
1260
1261         if (cookie == chan->bus_error)
1262                 return DMA_ERROR;
1263
1264         ret = dma_cookie_status(dchan, cookie, txstate);
1265         if (likely(txstate && (ret != DMA_ERROR)))
1266                 dma_set_residue(txstate, pxad_residue(chan, cookie));
1267
1268         return ret;
1269 }
1270
1271 static void pxad_synchronize(struct dma_chan *dchan)
1272 {
1273         struct pxad_chan *chan = to_pxad_chan(dchan);
1274
1275         wait_event(chan->wq_state, !is_chan_running(chan));
1276         vchan_synchronize(&chan->vc);
1277 }
1278
1279 static void pxad_free_channels(struct dma_device *dmadev)
1280 {
1281         struct pxad_chan *c, *cn;
1282
1283         list_for_each_entry_safe(c, cn, &dmadev->channels,
1284                                  vc.chan.device_node) {
1285                 list_del(&c->vc.chan.device_node);
1286                 tasklet_kill(&c->vc.task);
1287         }
1288 }
1289
1290 static int pxad_remove(struct platform_device *op)
1291 {
1292         struct pxad_device *pdev = platform_get_drvdata(op);
1293
1294         pxad_cleanup_debugfs(pdev);
1295         pxad_free_channels(&pdev->slave);
1296         dma_async_device_unregister(&pdev->slave);
1297         return 0;
1298 }
1299
1300 static int pxad_init_phys(struct platform_device *op,
1301                           struct pxad_device *pdev,
1302                           unsigned int nb_phy_chans)
1303 {
1304         int irq0, irq, nr_irq = 0, i, ret;
1305         struct pxad_phy *phy;
1306
1307         irq0 = platform_get_irq(op, 0);
1308         if (irq0 < 0)
1309                 return irq0;
1310
1311         pdev->phys = devm_kcalloc(&op->dev, nb_phy_chans,
1312                                   sizeof(pdev->phys[0]), GFP_KERNEL);
1313         if (!pdev->phys)
1314                 return -ENOMEM;
1315
1316         for (i = 0; i < nb_phy_chans; i++)
1317                 if (platform_get_irq(op, i) > 0)
1318                         nr_irq++;
1319
1320         for (i = 0; i < nb_phy_chans; i++) {
1321                 phy = &pdev->phys[i];
1322                 phy->base = pdev->base;
1323                 phy->idx = i;
1324                 irq = platform_get_irq(op, i);
1325                 if ((nr_irq > 1) && (irq > 0))
1326                         ret = devm_request_irq(&op->dev, irq,
1327                                                pxad_chan_handler,
1328                                                IRQF_SHARED, "pxa-dma", phy);
1329                 if ((nr_irq == 1) && (i == 0))
1330                         ret = devm_request_irq(&op->dev, irq0,
1331                                                pxad_int_handler,
1332                                                IRQF_SHARED, "pxa-dma", pdev);
1333                 if (ret) {
1334                         dev_err(pdev->slave.dev,
1335                                 "%s(): can't request irq %d:%d\n", __func__,
1336                                 irq, ret);
1337                         return ret;
1338                 }
1339         }
1340
1341         return 0;
1342 }
1343
1344 static const struct of_device_id pxad_dt_ids[] = {
1345         { .compatible = "marvell,pdma-1.0", },
1346         {}
1347 };
1348 MODULE_DEVICE_TABLE(of, pxad_dt_ids);
1349
1350 static struct dma_chan *pxad_dma_xlate(struct of_phandle_args *dma_spec,
1351                                            struct of_dma *ofdma)
1352 {
1353         struct pxad_device *d = ofdma->of_dma_data;
1354         struct dma_chan *chan;
1355
1356         chan = dma_get_any_slave_channel(&d->slave);
1357         if (!chan)
1358                 return NULL;
1359
1360         to_pxad_chan(chan)->drcmr = dma_spec->args[0];
1361         to_pxad_chan(chan)->prio = dma_spec->args[1];
1362
1363         return chan;
1364 }
1365
1366 static int pxad_init_dmadev(struct platform_device *op,
1367                             struct pxad_device *pdev,
1368                             unsigned int nr_phy_chans,
1369                             unsigned int nr_requestors)
1370 {
1371         int ret;
1372         unsigned int i;
1373         struct pxad_chan *c;
1374
1375         pdev->nr_chans = nr_phy_chans;
1376         pdev->nr_requestors = nr_requestors;
1377         INIT_LIST_HEAD(&pdev->slave.channels);
1378         pdev->slave.device_alloc_chan_resources = pxad_alloc_chan_resources;
1379         pdev->slave.device_free_chan_resources = pxad_free_chan_resources;
1380         pdev->slave.device_tx_status = pxad_tx_status;
1381         pdev->slave.device_issue_pending = pxad_issue_pending;
1382         pdev->slave.device_config = pxad_config;
1383         pdev->slave.device_synchronize = pxad_synchronize;
1384         pdev->slave.device_terminate_all = pxad_terminate_all;
1385
1386         if (op->dev.coherent_dma_mask)
1387                 dma_set_mask(&op->dev, op->dev.coherent_dma_mask);
1388         else
1389                 dma_set_mask(&op->dev, DMA_BIT_MASK(32));
1390
1391         ret = pxad_init_phys(op, pdev, nr_phy_chans);
1392         if (ret)
1393                 return ret;
1394
1395         for (i = 0; i < nr_phy_chans; i++) {
1396                 c = devm_kzalloc(&op->dev, sizeof(*c), GFP_KERNEL);
1397                 if (!c)
1398                         return -ENOMEM;
1399                 c->vc.desc_free = pxad_free_desc;
1400                 vchan_init(&c->vc, &pdev->slave);
1401                 init_waitqueue_head(&c->wq_state);
1402         }
1403
1404         return dma_async_device_register(&pdev->slave);
1405 }
1406
1407 static int pxad_probe(struct platform_device *op)
1408 {
1409         struct pxad_device *pdev;
1410         const struct of_device_id *of_id;
1411         struct mmp_dma_platdata *pdata = dev_get_platdata(&op->dev);
1412         struct resource *iores;
1413         int ret, dma_channels = 0, nb_requestors = 0;
1414         const enum dma_slave_buswidth widths =
1415                 DMA_SLAVE_BUSWIDTH_1_BYTE   | DMA_SLAVE_BUSWIDTH_2_BYTES |
1416                 DMA_SLAVE_BUSWIDTH_4_BYTES;
1417
1418         pdev = devm_kzalloc(&op->dev, sizeof(*pdev), GFP_KERNEL);
1419         if (!pdev)
1420                 return -ENOMEM;
1421
1422         spin_lock_init(&pdev->phy_lock);
1423
1424         iores = platform_get_resource(op, IORESOURCE_MEM, 0);
1425         pdev->base = devm_ioremap_resource(&op->dev, iores);
1426         if (IS_ERR(pdev->base))
1427                 return PTR_ERR(pdev->base);
1428
1429         of_id = of_match_device(pxad_dt_ids, &op->dev);
1430         if (of_id) {
1431                 of_property_read_u32(op->dev.of_node, "#dma-channels",
1432                                      &dma_channels);
1433                 ret = of_property_read_u32(op->dev.of_node, "#dma-requests",
1434                                            &nb_requestors);
1435                 if (ret) {
1436                         dev_warn(pdev->slave.dev,
1437                                  "#dma-requests set to default 32 as missing in OF: %d",
1438                                  ret);
1439                         nb_requestors = 32;
1440                 };
1441         } else if (pdata && pdata->dma_channels) {
1442                 dma_channels = pdata->dma_channels;
1443                 nb_requestors = pdata->nb_requestors;
1444         } else {
1445                 dma_channels = 32;      /* default 32 channel */
1446         }
1447
1448         dma_cap_set(DMA_SLAVE, pdev->slave.cap_mask);
1449         dma_cap_set(DMA_MEMCPY, pdev->slave.cap_mask);
1450         dma_cap_set(DMA_CYCLIC, pdev->slave.cap_mask);
1451         dma_cap_set(DMA_PRIVATE, pdev->slave.cap_mask);
1452         pdev->slave.device_prep_dma_memcpy = pxad_prep_memcpy;
1453         pdev->slave.device_prep_slave_sg = pxad_prep_slave_sg;
1454         pdev->slave.device_prep_dma_cyclic = pxad_prep_dma_cyclic;
1455
1456         pdev->slave.copy_align = PDMA_ALIGNMENT;
1457         pdev->slave.src_addr_widths = widths;
1458         pdev->slave.dst_addr_widths = widths;
1459         pdev->slave.directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
1460         pdev->slave.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
1461         pdev->slave.descriptor_reuse = true;
1462
1463         pdev->slave.dev = &op->dev;
1464         ret = pxad_init_dmadev(op, pdev, dma_channels, nb_requestors);
1465         if (ret) {
1466                 dev_err(pdev->slave.dev, "unable to register\n");
1467                 return ret;
1468         }
1469
1470         if (op->dev.of_node) {
1471                 /* Device-tree DMA controller registration */
1472                 ret = of_dma_controller_register(op->dev.of_node,
1473                                                  pxad_dma_xlate, pdev);
1474                 if (ret < 0) {
1475                         dev_err(pdev->slave.dev,
1476                                 "of_dma_controller_register failed\n");
1477                         return ret;
1478                 }
1479         }
1480
1481         platform_set_drvdata(op, pdev);
1482         pxad_init_debugfs(pdev);
1483         dev_info(pdev->slave.dev, "initialized %d channels on %d requestors\n",
1484                  dma_channels, nb_requestors);
1485         return 0;
1486 }
1487
1488 static const struct platform_device_id pxad_id_table[] = {
1489         { "pxa-dma", },
1490         { },
1491 };
1492
1493 static struct platform_driver pxad_driver = {
1494         .driver         = {
1495                 .name   = "pxa-dma",
1496                 .of_match_table = pxad_dt_ids,
1497         },
1498         .id_table       = pxad_id_table,
1499         .probe          = pxad_probe,
1500         .remove         = pxad_remove,
1501 };
1502
1503 bool pxad_filter_fn(struct dma_chan *chan, void *param)
1504 {
1505         struct pxad_chan *c = to_pxad_chan(chan);
1506         struct pxad_param *p = param;
1507
1508         if (chan->device->dev->driver != &pxad_driver.driver)
1509                 return false;
1510
1511         c->drcmr = p->drcmr;
1512         c->prio = p->prio;
1513
1514         return true;
1515 }
1516 EXPORT_SYMBOL_GPL(pxad_filter_fn);
1517
1518 int pxad_toggle_reserved_channel(int legacy_channel)
1519 {
1520         if (legacy_unavailable & (BIT(legacy_channel)))
1521                 return -EBUSY;
1522         legacy_reserved ^= BIT(legacy_channel);
1523         return 0;
1524 }
1525 EXPORT_SYMBOL_GPL(pxad_toggle_reserved_channel);
1526
1527 module_platform_driver(pxad_driver);
1528
1529 MODULE_DESCRIPTION("Marvell PXA Peripheral DMA Driver");
1530 MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
1531 MODULE_LICENSE("GPL v2");