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 static bool pxad_filter_fn(struct dma_chan *chan, void *param);
 183
 184 /*
 185  * Debug fs
 186  */
 187 #ifdef CONFIG_DEBUG_FS
 188 #include <linux/debugfs.h>
 189 #include <linux/uaccess.h>
 190 #include <linux/seq_file.h>
 191
 192 static int requester_chan_show(struct seq_file *s, void *p)
 193 {
 194         struct pxad_phy *phy = s->private;
 195         int i;
 196         u32 drcmr;
 197
 198         seq_printf(s, "DMA channel %d requester :\n", phy->idx);
 199         for (i = 0; i < 70; i++) {
 200                 drcmr = readl_relaxed(phy->base + pxad_drcmr(i));
 201                 if ((drcmr & DRCMR_CHLNUM) == phy->idx)
 202                         seq_printf(s, "\tRequester %d (MAPVLD=%d)\n", i,
 203                                    !!(drcmr & DRCMR_MAPVLD));
 204         }
 205         return 0;
 206 }
 207
 208 static inline int dbg_burst_from_dcmd(u32 dcmd)
 209 {
 210         int burst = (dcmd >> 16) & 0x3;
 211
 212         return burst ? 4 << burst : 0;
 213 }
 214
 215 static int is_phys_valid(unsigned long addr)
 216 {
 217         return pfn_valid(__phys_to_pfn(addr));
 218 }
 219
 220 #define PXA_DCSR_STR(flag) (dcsr & PXA_DCSR_##flag ? #flag" " : "")
 221 #define PXA_DCMD_STR(flag) (dcmd & PXA_DCMD_##flag ? #flag" " : "")
 222
 223 static int descriptors_show(struct seq_file *s, void *p)
 224 {
 225         struct pxad_phy *phy = s->private;
 226         int i, max_show = 20, burst, width;
 227         u32 dcmd;
 228         unsigned long phys_desc, ddadr;
 229         struct pxad_desc_hw *desc;
 230
 231         phys_desc = ddadr = _phy_readl_relaxed(phy, DDADR);
 232
 233         seq_printf(s, "DMA channel %d descriptors :\n", phy->idx);
 234         seq_printf(s, "[%03d] First descriptor unknown\n", 0);
 235         for (i = 1; i < max_show && is_phys_valid(phys_desc); i++) {
 236                 desc = phys_to_virt(phys_desc);
 237                 dcmd = desc->dcmd;
 238                 burst = dbg_burst_from_dcmd(dcmd);
 239                 width = (1 << ((dcmd >> 14) & 0x3)) >> 1;
 240
 241                 seq_printf(s, "[%03d] Desc at %08lx(virt %p)\n",
 242                            i, phys_desc, desc);
 243                 seq_printf(s, "\tDDADR = %08x\n", desc->ddadr);
 244                 seq_printf(s, "\tDSADR = %08x\n", desc->dsadr);
 245                 seq_printf(s, "\tDTADR = %08x\n", desc->dtadr);
 246                 seq_printf(s, "\tDCMD  = %08x (%s%s%s%s%s%s%sburst=%d width=%d len=%d)\n",
 247                            dcmd,
 248                            PXA_DCMD_STR(INCSRCADDR), PXA_DCMD_STR(INCTRGADDR),
 249                            PXA_DCMD_STR(FLOWSRC), PXA_DCMD_STR(FLOWTRG),
 250                            PXA_DCMD_STR(STARTIRQEN), PXA_DCMD_STR(ENDIRQEN),
 251                            PXA_DCMD_STR(ENDIAN), burst, width,
 252                            dcmd & PXA_DCMD_LENGTH);
 253                 phys_desc = desc->ddadr;
 254         }
 255         if (i == max_show)
 256                 seq_printf(s, "[%03d] Desc at %08lx ... max display reached\n",
 257                            i, phys_desc);
 258         else
 259                 seq_printf(s, "[%03d] Desc at %08lx is %s\n",
 260                            i, phys_desc, phys_desc == DDADR_STOP ?
 261                            "DDADR_STOP" : "invalid");
 262
 263         return 0;
 264 }
 265
 266 static int chan_state_show(struct seq_file *s, void *p)
 267 {
 268         struct pxad_phy *phy = s->private;
 269         u32 dcsr, dcmd;
 270         int burst, width;
 271         static const char * const str_prio[] = {
 272                 "high", "normal", "low", "invalid"
 273         };
 274
 275         dcsr = _phy_readl_relaxed(phy, DCSR);
 276         dcmd = _phy_readl_relaxed(phy, DCMD);
 277         burst = dbg_burst_from_dcmd(dcmd);
 278         width = (1 << ((dcmd >> 14) & 0x3)) >> 1;
 279
 280         seq_printf(s, "DMA channel %d\n", phy->idx);
 281         seq_printf(s, "\tPriority : %s\n",
 282                           str_prio[(phy->idx & 0xf) / 4]);
 283         seq_printf(s, "\tUnaligned transfer bit: %s\n",
 284                           _phy_readl_relaxed(phy, DALGN) & BIT(phy->idx) ?
 285                           "yes" : "no");
 286         seq_printf(s, "\tDCSR  = %08x (%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s)\n",
 287                    dcsr, PXA_DCSR_STR(RUN), PXA_DCSR_STR(NODESC),
 288                    PXA_DCSR_STR(STOPIRQEN), PXA_DCSR_STR(EORIRQEN),
 289                    PXA_DCSR_STR(EORJMPEN), PXA_DCSR_STR(EORSTOPEN),
 290                    PXA_DCSR_STR(SETCMPST), PXA_DCSR_STR(CLRCMPST),
 291                    PXA_DCSR_STR(CMPST), PXA_DCSR_STR(EORINTR),
 292                    PXA_DCSR_STR(REQPEND), PXA_DCSR_STR(STOPSTATE),
 293                    PXA_DCSR_STR(ENDINTR), PXA_DCSR_STR(STARTINTR),
 294                    PXA_DCSR_STR(BUSERR));
 295
 296         seq_printf(s, "\tDCMD  = %08x (%s%s%s%s%s%s%sburst=%d width=%d len=%d)\n",
 297                    dcmd,
 298                    PXA_DCMD_STR(INCSRCADDR), PXA_DCMD_STR(INCTRGADDR),
 299                    PXA_DCMD_STR(FLOWSRC), PXA_DCMD_STR(FLOWTRG),
 300                    PXA_DCMD_STR(STARTIRQEN), PXA_DCMD_STR(ENDIRQEN),
 301                    PXA_DCMD_STR(ENDIAN), burst, width, dcmd & PXA_DCMD_LENGTH);
 302         seq_printf(s, "\tDSADR = %08x\n", _phy_readl_relaxed(phy, DSADR));
 303         seq_printf(s, "\tDTADR = %08x\n", _phy_readl_relaxed(phy, DTADR));
 304         seq_printf(s, "\tDDADR = %08x\n", _phy_readl_relaxed(phy, DDADR));
 305
 306         return 0;
 307 }
 308
 309 static int state_show(struct seq_file *s, void *p)
 310 {
 311         struct pxad_device *pdev = s->private;
 312
 313         /* basic device status */
 314         seq_puts(s, "DMA engine status\n");
 315         seq_printf(s, "\tChannel number: %d\n", pdev->nr_chans);
 316
 317         return 0;
 318 }
 319
 320 DEFINE_SHOW_ATTRIBUTE(state);
 321 DEFINE_SHOW_ATTRIBUTE(chan_state);
 322 DEFINE_SHOW_ATTRIBUTE(descriptors);
 323 DEFINE_SHOW_ATTRIBUTE(requester_chan);
 324
 325 static struct dentry *pxad_dbg_alloc_chan(struct pxad_device *pdev,
 326                                              int ch, struct dentry *chandir)
 327 {
 328         char chan_name[11];
 329         struct dentry *chan, *chan_state = NULL, *chan_descr = NULL;
 330         struct dentry *chan_reqs = NULL;
 331         void *dt;
 332
 333         scnprintf(chan_name, sizeof(chan_name), "%d", ch);
 334         chan = debugfs_create_dir(chan_name, chandir);
 335         dt = (void *)&pdev->phys[ch];
 336
 337         if (chan)
 338                 chan_state = debugfs_create_file("state", 0400, chan, dt,
 339                                                  &chan_state_fops);
 340         if (chan_state)
 341                 chan_descr = debugfs_create_file("descriptors", 0400, chan, dt,
 342                                                  &descriptors_fops);
 343         if (chan_descr)
 344                 chan_reqs = debugfs_create_file("requesters", 0400, chan, dt,
 345                                                 &requester_chan_fops);
 346         if (!chan_reqs)
 347                 goto err_state;
 348
 349         return chan;
 350
 351 err_state:
 352         debugfs_remove_recursive(chan);
 353         return NULL;
 354 }
 355
 356 static void pxad_init_debugfs(struct pxad_device *pdev)
 357 {
 358         int i;
 359         struct dentry *chandir;
 360
 361         pdev->dbgfs_root = debugfs_create_dir(dev_name(pdev->slave.dev), NULL);
 362         if (IS_ERR(pdev->dbgfs_root) || !pdev->dbgfs_root)
 363                 goto err_root;
 364
 365         pdev->dbgfs_state = debugfs_create_file("state", 0400, pdev->dbgfs_root,
 366                                                 pdev, &state_fops);
 367         if (!pdev->dbgfs_state)
 368                 goto err_state;
 369
 370         pdev->dbgfs_chan =
 371                 kmalloc_array(pdev->nr_chans, sizeof(*pdev->dbgfs_state),
 372                               GFP_KERNEL);
 373         if (!pdev->dbgfs_chan)
 374                 goto err_alloc;
 375
 376         chandir = debugfs_create_dir("channels", pdev->dbgfs_root);
 377         if (!chandir)
 378                 goto err_chandir;
 379
 380         for (i = 0; i < pdev->nr_chans; i++) {
 381                 pdev->dbgfs_chan[i] = pxad_dbg_alloc_chan(pdev, i, chandir);
 382                 if (!pdev->dbgfs_chan[i])
 383                         goto err_chans;
 384         }
 385
 386         return;
 387 err_chans:
 388 err_chandir:
 389         kfree(pdev->dbgfs_chan);
 390 err_alloc:
 391 err_state:
 392         debugfs_remove_recursive(pdev->dbgfs_root);
 393 err_root:
 394         pr_err("pxad: debugfs is not available\n");
 395 }
 396
 397 static void pxad_cleanup_debugfs(struct pxad_device *pdev)
 398 {
 399         debugfs_remove_recursive(pdev->dbgfs_root);
 400 }
 401 #else
 402 static inline void pxad_init_debugfs(struct pxad_device *pdev) {}
 403 static inline void pxad_cleanup_debugfs(struct pxad_device *pdev) {}
 404 #endif
 405
 406 static struct pxad_phy *lookup_phy(struct pxad_chan *pchan)
 407 {
 408         int prio, i;
 409         struct pxad_device *pdev = to_pxad_dev(pchan->vc.chan.device);
 410         struct pxad_phy *phy, *found = NULL;
 411         unsigned long flags;
 412
 413         /*
 414          * dma channel priorities
 415          * ch 0 - 3,  16 - 19  <--> (0)
 416          * ch 4 - 7,  20 - 23  <--> (1)
 417          * ch 8 - 11, 24 - 27  <--> (2)
 418          * ch 12 - 15, 28 - 31  <--> (3)
 419          */
 420
 421         spin_lock_irqsave(&pdev->phy_lock, flags);
 422         for (prio = pchan->prio; prio >= PXAD_PRIO_HIGHEST; prio--) {
 423                 for (i = 0; i < pdev->nr_chans; i++) {
 424                         if (prio != (i & 0xf) >> 2)
 425                                 continue;
 426                         phy = &pdev->phys[i];
 427                         if (!phy->vchan) {
 428                                 phy->vchan = pchan;
 429                                 found = phy;
 430                                 goto out_unlock;
 431                         }
 432                 }
 433         }
 434
 435 out_unlock:
 436         spin_unlock_irqrestore(&pdev->phy_lock, flags);
 437         dev_dbg(&pchan->vc.chan.dev->device,
 438                 "%s(): phy=%p(%d)\n", __func__, found,
 439                 found ? found->idx : -1);
 440
 441         return found;
 442 }
 443
 444 static void pxad_free_phy(struct pxad_chan *chan)
 445 {
 446         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
 447         unsigned long flags;
 448         u32 reg;
 449
 450         dev_dbg(&chan->vc.chan.dev->device,
 451                 "%s(): freeing\n", __func__);
 452         if (!chan->phy)
 453                 return;
 454
 455         /* clear the channel mapping in DRCMR */
 456         if (chan->drcmr <= pdev->nr_requestors) {
 457                 reg = pxad_drcmr(chan->drcmr);
 458                 writel_relaxed(0, chan->phy->base + reg);
 459         }
 460
 461         spin_lock_irqsave(&pdev->phy_lock, flags);
 462         chan->phy->vchan = NULL;
 463         chan->phy = NULL;
 464         spin_unlock_irqrestore(&pdev->phy_lock, flags);
 465 }
 466
 467 static bool is_chan_running(struct pxad_chan *chan)
 468 {
 469         u32 dcsr;
 470         struct pxad_phy *phy = chan->phy;
 471
 472         if (!phy)
 473                 return false;
 474         dcsr = phy_readl_relaxed(phy, DCSR);
 475         return dcsr & PXA_DCSR_RUN;
 476 }
 477
 478 static bool is_running_chan_misaligned(struct pxad_chan *chan)
 479 {
 480         u32 dalgn;
 481
 482         BUG_ON(!chan->phy);
 483         dalgn = phy_readl_relaxed(chan->phy, DALGN);
 484         return dalgn & (BIT(chan->phy->idx));
 485 }
 486
 487 static void phy_enable(struct pxad_phy *phy, bool misaligned)
 488 {
 489         struct pxad_device *pdev;
 490         u32 reg, dalgn;
 491
 492         if (!phy->vchan)
 493                 return;
 494
 495         dev_dbg(&phy->vchan->vc.chan.dev->device,
 496                 "%s(); phy=%p(%d) misaligned=%d\n", __func__,
 497                 phy, phy->idx, misaligned);
 498
 499         pdev = to_pxad_dev(phy->vchan->vc.chan.device);
 500         if (phy->vchan->drcmr <= pdev->nr_requestors) {
 501                 reg = pxad_drcmr(phy->vchan->drcmr);
 502                 writel_relaxed(DRCMR_MAPVLD | phy->idx, phy->base + reg);
 503         }
 504
 505         dalgn = phy_readl_relaxed(phy, DALGN);
 506         if (misaligned)
 507                 dalgn |= BIT(phy->idx);
 508         else
 509                 dalgn &= ~BIT(phy->idx);
 510         phy_writel_relaxed(phy, dalgn, DALGN);
 511
 512         phy_writel(phy, PXA_DCSR_STOPIRQEN | PXA_DCSR_ENDINTR |
 513                    PXA_DCSR_BUSERR | PXA_DCSR_RUN, DCSR);
 514 }
 515
 516 static void phy_disable(struct pxad_phy *phy)
 517 {
 518         u32 dcsr;
 519
 520         if (!phy)
 521                 return;
 522
 523         dcsr = phy_readl_relaxed(phy, DCSR);
 524         dev_dbg(&phy->vchan->vc.chan.dev->device,
 525                 "%s(): phy=%p(%d)\n", __func__, phy, phy->idx);
 526         phy_writel(phy, dcsr & ~PXA_DCSR_RUN & ~PXA_DCSR_STOPIRQEN, DCSR);
 527 }
 528
 529 static void pxad_launch_chan(struct pxad_chan *chan,
 530                                  struct pxad_desc_sw *desc)
 531 {
 532         dev_dbg(&chan->vc.chan.dev->device,
 533                 "%s(): desc=%p\n", __func__, desc);
 534         if (!chan->phy) {
 535                 chan->phy = lookup_phy(chan);
 536                 if (!chan->phy) {
 537                         dev_dbg(&chan->vc.chan.dev->device,
 538                                 "%s(): no free dma channel\n", __func__);
 539                         return;
 540                 }
 541         }
 542         chan->bus_error = 0;
 543
 544         /*
 545          * Program the descriptor's address into the DMA controller,
 546          * then start the DMA transaction
 547          */
 548         phy_writel(chan->phy, desc->first, DDADR);
 549         phy_enable(chan->phy, chan->misaligned);
 550         wake_up(&chan->wq_state);
 551 }
 552
 553 static void set_updater_desc(struct pxad_desc_sw *sw_desc,
 554                              unsigned long flags)
 555 {
 556         struct pxad_desc_hw *updater =
 557                 sw_desc->hw_desc[sw_desc->nb_desc - 1];
 558         dma_addr_t dma = sw_desc->hw_desc[sw_desc->nb_desc - 2]->ddadr;
 559
 560         updater->ddadr = DDADR_STOP;
 561         updater->dsadr = dma;
 562         updater->dtadr = dma + 8;
 563         updater->dcmd = PXA_DCMD_WIDTH4 | PXA_DCMD_BURST32 |
 564                 (PXA_DCMD_LENGTH & sizeof(u32));
 565         if (flags & DMA_PREP_INTERRUPT)
 566                 updater->dcmd |= PXA_DCMD_ENDIRQEN;
 567         if (sw_desc->cyclic)
 568                 sw_desc->hw_desc[sw_desc->nb_desc - 2]->ddadr = sw_desc->first;
 569 }
 570
 571 static bool is_desc_completed(struct virt_dma_desc *vd)
 572 {
 573         struct pxad_desc_sw *sw_desc = to_pxad_sw_desc(vd);
 574         struct pxad_desc_hw *updater =
 575                 sw_desc->hw_desc[sw_desc->nb_desc - 1];
 576
 577         return updater->dtadr != (updater->dsadr + 8);
 578 }
 579
 580 static void pxad_desc_chain(struct virt_dma_desc *vd1,
 581                                 struct virt_dma_desc *vd2)
 582 {
 583         struct pxad_desc_sw *desc1 = to_pxad_sw_desc(vd1);
 584         struct pxad_desc_sw *desc2 = to_pxad_sw_desc(vd2);
 585         dma_addr_t dma_to_chain;
 586
 587         dma_to_chain = desc2->first;
 588         desc1->hw_desc[desc1->nb_desc - 1]->ddadr = dma_to_chain;
 589 }
 590
 591 static bool pxad_try_hotchain(struct virt_dma_chan *vc,
 592                                   struct virt_dma_desc *vd)
 593 {
 594         struct virt_dma_desc *vd_last_issued = NULL;
 595         struct pxad_chan *chan = to_pxad_chan(&vc->chan);
 596
 597         /*
 598          * Attempt to hot chain the tx if the phy is still running. This is
 599          * considered successful only if either the channel is still running
 600          * after the chaining, or if the chained transfer is completed after
 601          * having been hot chained.
 602          * A change of alignment is not allowed, and forbids hotchaining.
 603          */
 604         if (is_chan_running(chan)) {
 605                 BUG_ON(list_empty(&vc->desc_issued));
 606
 607                 if (!is_running_chan_misaligned(chan) &&
 608                     to_pxad_sw_desc(vd)->misaligned)
 609                         return false;
 610
 611                 vd_last_issued = list_entry(vc->desc_issued.prev,
 612                                             struct virt_dma_desc, node);
 613                 pxad_desc_chain(vd_last_issued, vd);
 614                 if (is_chan_running(chan) || is_desc_completed(vd))
 615                         return true;
 616         }
 617
 618         return false;
 619 }
 620
 621 static unsigned int clear_chan_irq(struct pxad_phy *phy)
 622 {
 623         u32 dcsr;
 624         u32 dint = readl(phy->base + DINT);
 625
 626         if (!(dint & BIT(phy->idx)))
 627                 return PXA_DCSR_RUN;
 628
 629         /* clear irq */
 630         dcsr = phy_readl_relaxed(phy, DCSR);
 631         phy_writel(phy, dcsr, DCSR);
 632         if ((dcsr & PXA_DCSR_BUSERR) && (phy->vchan))
 633                 dev_warn(&phy->vchan->vc.chan.dev->device,
 634                          "%s(chan=%p): PXA_DCSR_BUSERR\n",
 635                          __func__, &phy->vchan);
 636
 637         return dcsr & ~PXA_DCSR_RUN;
 638 }
 639
 640 static irqreturn_t pxad_chan_handler(int irq, void *dev_id)
 641 {
 642         struct pxad_phy *phy = dev_id;
 643         struct pxad_chan *chan = phy->vchan;
 644         struct virt_dma_desc *vd, *tmp;
 645         unsigned int dcsr;
 646         unsigned long flags;
 647         bool vd_completed;
 648         dma_cookie_t last_started = 0;
 649
 650         BUG_ON(!chan);
 651
 652         dcsr = clear_chan_irq(phy);
 653         if (dcsr & PXA_DCSR_RUN)
 654                 return IRQ_NONE;
 655
 656         spin_lock_irqsave(&chan->vc.lock, flags);
 657         list_for_each_entry_safe(vd, tmp, &chan->vc.desc_issued, node) {
 658                 vd_completed = is_desc_completed(vd);
 659                 dev_dbg(&chan->vc.chan.dev->device,
 660                         "%s(): checking txd %p[%x]: completed=%d dcsr=0x%x\n",
 661                         __func__, vd, vd->tx.cookie, vd_completed,
 662                         dcsr);
 663                 last_started = vd->tx.cookie;
 664                 if (to_pxad_sw_desc(vd)->cyclic) {
 665                         vchan_cyclic_callback(vd);
 666                         break;
 667                 }
 668                 if (vd_completed) {
 669                         list_del(&vd->node);
 670                         vchan_cookie_complete(vd);
 671                 } else {
 672                         break;
 673                 }
 674         }
 675
 676         if (dcsr & PXA_DCSR_BUSERR) {
 677                 chan->bus_error = last_started;
 678                 phy_disable(phy);
 679         }
 680
 681         if (!chan->bus_error && dcsr & PXA_DCSR_STOPSTATE) {
 682                 dev_dbg(&chan->vc.chan.dev->device,
 683                 "%s(): channel stopped, submitted_empty=%d issued_empty=%d",
 684                         __func__,
 685                         list_empty(&chan->vc.desc_submitted),
 686                         list_empty(&chan->vc.desc_issued));
 687                 phy_writel_relaxed(phy, dcsr & ~PXA_DCSR_STOPIRQEN, DCSR);
 688
 689                 if (list_empty(&chan->vc.desc_issued)) {
 690                         chan->misaligned =
 691                                 !list_empty(&chan->vc.desc_submitted);
 692                 } else {
 693                         vd = list_first_entry(&chan->vc.desc_issued,
 694                                               struct virt_dma_desc, node);
 695                         pxad_launch_chan(chan, to_pxad_sw_desc(vd));
 696                 }
 697         }
 698         spin_unlock_irqrestore(&chan->vc.lock, flags);
 699         wake_up(&chan->wq_state);
 700
 701         return IRQ_HANDLED;
 702 }
 703
 704 static irqreturn_t pxad_int_handler(int irq, void *dev_id)
 705 {
 706         struct pxad_device *pdev = dev_id;
 707         struct pxad_phy *phy;
 708         u32 dint = readl(pdev->base + DINT);
 709         int i, ret = IRQ_NONE;
 710
 711         while (dint) {
 712                 i = __ffs(dint);
 713                 dint &= (dint - 1);
 714                 phy = &pdev->phys[i];
 715                 if (pxad_chan_handler(irq, phy) == IRQ_HANDLED)
 716                         ret = IRQ_HANDLED;
 717         }
 718
 719         return ret;
 720 }
 721
 722 static int pxad_alloc_chan_resources(struct dma_chan *dchan)
 723 {
 724         struct pxad_chan *chan = to_pxad_chan(dchan);
 725         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
 726
 727         if (chan->desc_pool)
 728                 return 1;
 729
 730         chan->desc_pool = dma_pool_create(dma_chan_name(dchan),
 731                                           pdev->slave.dev,
 732                                           sizeof(struct pxad_desc_hw),
 733                                           __alignof__(struct pxad_desc_hw),
 734                                           0);
 735         if (!chan->desc_pool) {
 736                 dev_err(&chan->vc.chan.dev->device,
 737                         "%s(): unable to allocate descriptor pool\n",
 738                         __func__);
 739                 return -ENOMEM;
 740         }
 741
 742         return 1;
 743 }
 744
 745 static void pxad_free_chan_resources(struct dma_chan *dchan)
 746 {
 747         struct pxad_chan *chan = to_pxad_chan(dchan);
 748
 749         vchan_free_chan_resources(&chan->vc);
 750         dma_pool_destroy(chan->desc_pool);
 751         chan->desc_pool = NULL;
 752
 753         chan->drcmr = U32_MAX;
 754         chan->prio = PXAD_PRIO_LOWEST;
 755 }
 756
 757 static void pxad_free_desc(struct virt_dma_desc *vd)
 758 {
 759         int i;
 760         dma_addr_t dma;
 761         struct pxad_desc_sw *sw_desc = to_pxad_sw_desc(vd);
 762
 763         BUG_ON(sw_desc->nb_desc == 0);
 764         for (i = sw_desc->nb_desc - 1; i >= 0; i--) {
 765                 if (i > 0)
 766                         dma = sw_desc->hw_desc[i - 1]->ddadr;
 767                 else
 768                         dma = sw_desc->first;
 769                 dma_pool_free(sw_desc->desc_pool,
 770                               sw_desc->hw_desc[i], dma);
 771         }
 772         sw_desc->nb_desc = 0;
 773         kfree(sw_desc);
 774 }
 775
 776 static struct pxad_desc_sw *
 777 pxad_alloc_desc(struct pxad_chan *chan, unsigned int nb_hw_desc)
 778 {
 779         struct pxad_desc_sw *sw_desc;
 780         dma_addr_t dma;
 781         int i;
 782
 783         sw_desc = kzalloc(sizeof(*sw_desc) +
 784                           nb_hw_desc * sizeof(struct pxad_desc_hw *),
 785                           GFP_NOWAIT);
 786         if (!sw_desc)
 787                 return NULL;
 788         sw_desc->desc_pool = chan->desc_pool;
 789
 790         for (i = 0; i < nb_hw_desc; i++) {
 791                 sw_desc->hw_desc[i] = dma_pool_alloc(sw_desc->desc_pool,
 792                                                      GFP_NOWAIT, &dma);
 793                 if (!sw_desc->hw_desc[i]) {
 794                         dev_err(&chan->vc.chan.dev->device,
 795                                 "%s(): Couldn't allocate the %dth hw_desc from dma_pool %p\n",
 796                                 __func__, i, sw_desc->desc_pool);
 797                         goto err;
 798                 }
 799
 800                 if (i == 0)
 801                         sw_desc->first = dma;
 802                 else
 803                         sw_desc->hw_desc[i - 1]->ddadr = dma;
 804                 sw_desc->nb_desc++;
 805         }
 806
 807         return sw_desc;
 808 err:
 809         pxad_free_desc(&sw_desc->vd);
 810         return NULL;
 811 }
 812
 813 static dma_cookie_t pxad_tx_submit(struct dma_async_tx_descriptor *tx)
 814 {
 815         struct virt_dma_chan *vc = to_virt_chan(tx->chan);
 816         struct pxad_chan *chan = to_pxad_chan(&vc->chan);
 817         struct virt_dma_desc *vd_chained = NULL,
 818                 *vd = container_of(tx, struct virt_dma_desc, tx);
 819         dma_cookie_t cookie;
 820         unsigned long flags;
 821
 822         set_updater_desc(to_pxad_sw_desc(vd), tx->flags);
 823
 824         spin_lock_irqsave(&vc->lock, flags);
 825         cookie = dma_cookie_assign(tx);
 826
 827         if (list_empty(&vc->desc_submitted) && pxad_try_hotchain(vc, vd)) {
 828                 list_move_tail(&vd->node, &vc->desc_issued);
 829                 dev_dbg(&chan->vc.chan.dev->device,
 830                         "%s(): txd %p[%x]: submitted (hot linked)\n",
 831                         __func__, vd, cookie);
 832                 goto out;
 833         }
 834
 835         /*
 836          * Fallback to placing the tx in the submitted queue
 837          */
 838         if (!list_empty(&vc->desc_submitted)) {
 839                 vd_chained = list_entry(vc->desc_submitted.prev,
 840                                         struct virt_dma_desc, node);
 841                 /*
 842                  * Only chain the descriptors if no new misalignment is
 843                  * introduced. If a new misalignment is chained, let the channel
 844                  * stop, and be relaunched in misalign mode from the irq
 845                  * handler.
 846                  */
 847                 if (chan->misaligned || !to_pxad_sw_desc(vd)->misaligned)
 848                         pxad_desc_chain(vd_chained, vd);
 849                 else
 850                         vd_chained = NULL;
 851         }
 852         dev_dbg(&chan->vc.chan.dev->device,
 853                 "%s(): txd %p[%x]: submitted (%s linked)\n",
 854                 __func__, vd, cookie, vd_chained ? "cold" : "not");
 855         list_move_tail(&vd->node, &vc->desc_submitted);
 856         chan->misaligned |= to_pxad_sw_desc(vd)->misaligned;
 857
 858 out:
 859         spin_unlock_irqrestore(&vc->lock, flags);
 860         return cookie;
 861 }
 862
 863 static void pxad_issue_pending(struct dma_chan *dchan)
 864 {
 865         struct pxad_chan *chan = to_pxad_chan(dchan);
 866         struct virt_dma_desc *vd_first;
 867         unsigned long flags;
 868
 869         spin_lock_irqsave(&chan->vc.lock, flags);
 870         if (list_empty(&chan->vc.desc_submitted))
 871                 goto out;
 872
 873         vd_first = list_first_entry(&chan->vc.desc_submitted,
 874                                     struct virt_dma_desc, node);
 875         dev_dbg(&chan->vc.chan.dev->device,
 876                 "%s(): txd %p[%x]", __func__, vd_first, vd_first->tx.cookie);
 877
 878         vchan_issue_pending(&chan->vc);
 879         if (!pxad_try_hotchain(&chan->vc, vd_first))
 880                 pxad_launch_chan(chan, to_pxad_sw_desc(vd_first));
 881 out:
 882         spin_unlock_irqrestore(&chan->vc.lock, flags);
 883 }
 884
 885 static inline struct dma_async_tx_descriptor *
 886 pxad_tx_prep(struct virt_dma_chan *vc, struct virt_dma_desc *vd,
 887                  unsigned long tx_flags)
 888 {
 889         struct dma_async_tx_descriptor *tx;
 890         struct pxad_chan *chan = container_of(vc, struct pxad_chan, vc);
 891
 892         INIT_LIST_HEAD(&vd->node);
 893         tx = vchan_tx_prep(vc, vd, tx_flags);
 894         tx->tx_submit = pxad_tx_submit;
 895         dev_dbg(&chan->vc.chan.dev->device,
 896                 "%s(): vc=%p txd=%p[%x] flags=0x%lx\n", __func__,
 897                 vc, vd, vd->tx.cookie,
 898                 tx_flags);
 899
 900         return tx;
 901 }
 902
 903 static void pxad_get_config(struct pxad_chan *chan,
 904                             enum dma_transfer_direction dir,
 905                             u32 *dcmd, u32 *dev_src, u32 *dev_dst)
 906 {
 907         u32 maxburst = 0, dev_addr = 0;
 908         enum dma_slave_buswidth width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
 909         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
 910
 911         *dcmd = 0;
 912         if (dir == DMA_DEV_TO_MEM) {
 913                 maxburst = chan->cfg.src_maxburst;
 914                 width = chan->cfg.src_addr_width;
 915                 dev_addr = chan->cfg.src_addr;
 916                 *dev_src = dev_addr;
 917                 *dcmd |= PXA_DCMD_INCTRGADDR;
 918                 if (chan->drcmr <= pdev->nr_requestors)
 919                         *dcmd |= PXA_DCMD_FLOWSRC;
 920         }
 921         if (dir == DMA_MEM_TO_DEV) {
 922                 maxburst = chan->cfg.dst_maxburst;
 923                 width = chan->cfg.dst_addr_width;
 924                 dev_addr = chan->cfg.dst_addr;
 925                 *dev_dst = dev_addr;
 926                 *dcmd |= PXA_DCMD_INCSRCADDR;
 927                 if (chan->drcmr <= pdev->nr_requestors)
 928                         *dcmd |= PXA_DCMD_FLOWTRG;
 929         }
 930         if (dir == DMA_MEM_TO_MEM)
 931                 *dcmd |= PXA_DCMD_BURST32 | PXA_DCMD_INCTRGADDR |
 932                         PXA_DCMD_INCSRCADDR;
 933
 934         dev_dbg(&chan->vc.chan.dev->device,
 935                 "%s(): dev_addr=0x%x maxburst=%d width=%d  dir=%d\n",
 936                 __func__, dev_addr, maxburst, width, dir);
 937
 938         if (width == DMA_SLAVE_BUSWIDTH_1_BYTE)
 939                 *dcmd |= PXA_DCMD_WIDTH1;
 940         else if (width == DMA_SLAVE_BUSWIDTH_2_BYTES)
 941                 *dcmd |= PXA_DCMD_WIDTH2;
 942         else if (width == DMA_SLAVE_BUSWIDTH_4_BYTES)
 943                 *dcmd |= PXA_DCMD_WIDTH4;
 944
 945         if (maxburst == 8)
 946                 *dcmd |= PXA_DCMD_BURST8;
 947         else if (maxburst == 16)
 948                 *dcmd |= PXA_DCMD_BURST16;
 949         else if (maxburst == 32)
 950                 *dcmd |= PXA_DCMD_BURST32;
 951
 952         /* FIXME: drivers should be ported over to use the filter
 953          * function. Once that's done, the following two lines can
 954          * be removed.
 955          */
 956         if (chan->cfg.slave_id)
 957                 chan->drcmr = chan->cfg.slave_id;
 958 }
 959
 960 static struct dma_async_tx_descriptor *
 961 pxad_prep_memcpy(struct dma_chan *dchan,
 962                  dma_addr_t dma_dst, dma_addr_t dma_src,
 963                  size_t len, unsigned long flags)
 964 {
 965         struct pxad_chan *chan = to_pxad_chan(dchan);
 966         struct pxad_desc_sw *sw_desc;
 967         struct pxad_desc_hw *hw_desc;
 968         u32 dcmd;
 969         unsigned int i, nb_desc = 0;
 970         size_t copy;
 971
 972         if (!dchan || !len)
 973                 return NULL;
 974
 975         dev_dbg(&chan->vc.chan.dev->device,
 976                 "%s(): dma_dst=0x%lx dma_src=0x%lx len=%zu flags=%lx\n",
 977                 __func__, (unsigned long)dma_dst, (unsigned long)dma_src,
 978                 len, flags);
 979         pxad_get_config(chan, DMA_MEM_TO_MEM, &dcmd, NULL, NULL);
 980
 981         nb_desc = DIV_ROUND_UP(len, PDMA_MAX_DESC_BYTES);
 982         sw_desc = pxad_alloc_desc(chan, nb_desc + 1);
 983         if (!sw_desc)
 984                 return NULL;
 985         sw_desc->len = len;
 986
 987         if (!IS_ALIGNED(dma_src, 1 << PDMA_ALIGNMENT) ||
 988             !IS_ALIGNED(dma_dst, 1 << PDMA_ALIGNMENT))
 989                 sw_desc->misaligned = true;
 990
 991         i = 0;
 992         do {
 993                 hw_desc = sw_desc->hw_desc[i++];
 994                 copy = min_t(size_t, len, PDMA_MAX_DESC_BYTES);
 995                 hw_desc->dcmd = dcmd | (PXA_DCMD_LENGTH & copy);
 996                 hw_desc->dsadr = dma_src;
 997                 hw_desc->dtadr = dma_dst;
 998                 len -= copy;
 999                 dma_src += copy;
1000                 dma_dst += copy;
1001         } while (len);
1002         set_updater_desc(sw_desc, flags);
1003
1004         return pxad_tx_prep(&chan->vc, &sw_desc->vd, flags);
1005 }
1006
1007 static struct dma_async_tx_descriptor *
1008 pxad_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
1009                    unsigned int sg_len, enum dma_transfer_direction dir,
1010                    unsigned long flags, void *context)
1011 {
1012         struct pxad_chan *chan = to_pxad_chan(dchan);
1013         struct pxad_desc_sw *sw_desc;
1014         size_t len, avail;
1015         struct scatterlist *sg;
1016         dma_addr_t dma;
1017         u32 dcmd, dsadr = 0, dtadr = 0;
1018         unsigned int nb_desc = 0, i, j = 0;
1019
1020         if ((sgl == NULL) || (sg_len == 0))
1021                 return NULL;
1022
1023         pxad_get_config(chan, dir, &dcmd, &dsadr, &dtadr);
1024         dev_dbg(&chan->vc.chan.dev->device,
1025                 "%s(): dir=%d flags=%lx\n", __func__, dir, flags);
1026
1027         for_each_sg(sgl, sg, sg_len, i)
1028                 nb_desc += DIV_ROUND_UP(sg_dma_len(sg), PDMA_MAX_DESC_BYTES);
1029         sw_desc = pxad_alloc_desc(chan, nb_desc + 1);
1030         if (!sw_desc)
1031                 return NULL;
1032
1033         for_each_sg(sgl, sg, sg_len, i) {
1034                 dma = sg_dma_address(sg);
1035                 avail = sg_dma_len(sg);
1036                 sw_desc->len += avail;
1037
1038                 do {
1039                         len = min_t(size_t, avail, PDMA_MAX_DESC_BYTES);
1040                         if (dma & 0x7)
1041                                 sw_desc->misaligned = true;
1042
1043                         sw_desc->hw_desc[j]->dcmd =
1044                                 dcmd | (PXA_DCMD_LENGTH & len);
1045                         sw_desc->hw_desc[j]->dsadr = dsadr ? dsadr : dma;
1046                         sw_desc->hw_desc[j++]->dtadr = dtadr ? dtadr : dma;
1047
1048                         dma += len;
1049                         avail -= len;
1050                 } while (avail);
1051         }
1052         set_updater_desc(sw_desc, flags);
1053
1054         return pxad_tx_prep(&chan->vc, &sw_desc->vd, flags);
1055 }
1056
1057 static struct dma_async_tx_descriptor *
1058 pxad_prep_dma_cyclic(struct dma_chan *dchan,
1059                      dma_addr_t buf_addr, size_t len, size_t period_len,
1060                      enum dma_transfer_direction dir, unsigned long flags)
1061 {
1062         struct pxad_chan *chan = to_pxad_chan(dchan);
1063         struct pxad_desc_sw *sw_desc;
1064         struct pxad_desc_hw **phw_desc;
1065         dma_addr_t dma;
1066         u32 dcmd, dsadr = 0, dtadr = 0;
1067         unsigned int nb_desc = 0;
1068
1069         if (!dchan || !len || !period_len)
1070                 return NULL;
1071         if ((dir != DMA_DEV_TO_MEM) && (dir != DMA_MEM_TO_DEV)) {
1072                 dev_err(&chan->vc.chan.dev->device,
1073                         "Unsupported direction for cyclic DMA\n");
1074                 return NULL;
1075         }
1076         /* the buffer length must be a multiple of period_len */
1077         if (len % period_len != 0 || period_len > PDMA_MAX_DESC_BYTES ||
1078             !IS_ALIGNED(period_len, 1 << PDMA_ALIGNMENT))
1079                 return NULL;
1080
1081         pxad_get_config(chan, dir, &dcmd, &dsadr, &dtadr);
1082         dcmd |= PXA_DCMD_ENDIRQEN | (PXA_DCMD_LENGTH & period_len);
1083         dev_dbg(&chan->vc.chan.dev->device,
1084                 "%s(): buf_addr=0x%lx len=%zu period=%zu dir=%d flags=%lx\n",
1085                 __func__, (unsigned long)buf_addr, len, period_len, dir, flags);
1086
1087         nb_desc = DIV_ROUND_UP(period_len, PDMA_MAX_DESC_BYTES);
1088         nb_desc *= DIV_ROUND_UP(len, period_len);
1089         sw_desc = pxad_alloc_desc(chan, nb_desc + 1);
1090         if (!sw_desc)
1091                 return NULL;
1092         sw_desc->cyclic = true;
1093         sw_desc->len = len;
1094
1095         phw_desc = sw_desc->hw_desc;
1096         dma = buf_addr;
1097         do {
1098                 phw_desc[0]->dsadr = dsadr ? dsadr : dma;
1099                 phw_desc[0]->dtadr = dtadr ? dtadr : dma;
1100                 phw_desc[0]->dcmd = dcmd;
1101                 phw_desc++;
1102                 dma += period_len;
1103                 len -= period_len;
1104         } while (len);
1105         set_updater_desc(sw_desc, flags);
1106
1107         return pxad_tx_prep(&chan->vc, &sw_desc->vd, flags);
1108 }
1109
1110 static int pxad_config(struct dma_chan *dchan,
1111                        struct dma_slave_config *cfg)
1112 {
1113         struct pxad_chan *chan = to_pxad_chan(dchan);
1114
1115         if (!dchan)
1116                 return -EINVAL;
1117
1118         chan->cfg = *cfg;
1119         return 0;
1120 }
1121
1122 static int pxad_terminate_all(struct dma_chan *dchan)
1123 {
1124         struct pxad_chan *chan = to_pxad_chan(dchan);
1125         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
1126         struct virt_dma_desc *vd = NULL;
1127         unsigned long flags;
1128         struct pxad_phy *phy;
1129         LIST_HEAD(head);
1130
1131         dev_dbg(&chan->vc.chan.dev->device,
1132                 "%s(): vchan %p: terminate all\n", __func__, &chan->vc);
1133
1134         spin_lock_irqsave(&chan->vc.lock, flags);
1135         vchan_get_all_descriptors(&chan->vc, &head);
1136
1137         list_for_each_entry(vd, &head, node) {
1138                 dev_dbg(&chan->vc.chan.dev->device,
1139                         "%s(): cancelling txd %p[%x] (completed=%d)", __func__,
1140                         vd, vd->tx.cookie, is_desc_completed(vd));
1141         }
1142
1143         phy = chan->phy;
1144         if (phy) {
1145                 phy_disable(chan->phy);
1146                 pxad_free_phy(chan);
1147                 chan->phy = NULL;
1148                 spin_lock(&pdev->phy_lock);
1149                 phy->vchan = NULL;
1150                 spin_unlock(&pdev->phy_lock);
1151         }
1152         spin_unlock_irqrestore(&chan->vc.lock, flags);
1153         vchan_dma_desc_free_list(&chan->vc, &head);
1154
1155         return 0;
1156 }
1157
1158 static unsigned int pxad_residue(struct pxad_chan *chan,
1159                                  dma_cookie_t cookie)
1160 {
1161         struct virt_dma_desc *vd = NULL;
1162         struct pxad_desc_sw *sw_desc = NULL;
1163         struct pxad_desc_hw *hw_desc = NULL;
1164         u32 curr, start, len, end, residue = 0;
1165         unsigned long flags;
1166         bool passed = false;
1167         int i;
1168
1169         /*
1170          * If the channel does not have a phy pointer anymore, it has already
1171          * been completed. Therefore, its residue is 0.
1172          */
1173         if (!chan->phy)
1174                 return 0;
1175
1176         spin_lock_irqsave(&chan->vc.lock, flags);
1177
1178         vd = vchan_find_desc(&chan->vc, cookie);
1179         if (!vd)
1180                 goto out;
1181
1182         sw_desc = to_pxad_sw_desc(vd);
1183         if (sw_desc->hw_desc[0]->dcmd & PXA_DCMD_INCSRCADDR)
1184                 curr = phy_readl_relaxed(chan->phy, DSADR);
1185         else
1186                 curr = phy_readl_relaxed(chan->phy, DTADR);
1187
1188         /*
1189          * curr has to be actually read before checking descriptor
1190          * completion, so that a curr inside a status updater
1191          * descriptor implies the following test returns true, and
1192          * preventing reordering of curr load and the test.
1193          */
1194         rmb();
1195         if (is_desc_completed(vd))
1196                 goto out;
1197
1198         for (i = 0; i < sw_desc->nb_desc - 1; i++) {
1199                 hw_desc = sw_desc->hw_desc[i];
1200                 if (sw_desc->hw_desc[0]->dcmd & PXA_DCMD_INCSRCADDR)
1201                         start = hw_desc->dsadr;
1202                 else
1203                         start = hw_desc->dtadr;
1204                 len = hw_desc->dcmd & PXA_DCMD_LENGTH;
1205                 end = start + len;
1206
1207                 /*
1208                  * 'passed' will be latched once we found the descriptor
1209                  * which lies inside the boundaries of the curr
1210                  * pointer. All descriptors that occur in the list
1211                  * _after_ we found that partially handled descriptor
1212                  * are still to be processed and are hence added to the
1213                  * residual bytes counter.
1214                  */
1215
1216                 if (passed) {
1217                         residue += len;
1218                 } else if (curr >= start && curr <= end) {
1219                         residue += end - curr;
1220                         passed = true;
1221                 }
1222         }
1223         if (!passed)
1224                 residue = sw_desc->len;
1225
1226 out:
1227         spin_unlock_irqrestore(&chan->vc.lock, flags);
1228         dev_dbg(&chan->vc.chan.dev->device,
1229                 "%s(): txd %p[%x] sw_desc=%p: %d\n",
1230                 __func__, vd, cookie, sw_desc, residue);
1231         return residue;
1232 }
1233
1234 static enum dma_status pxad_tx_status(struct dma_chan *dchan,
1235                                       dma_cookie_t cookie,
1236                                       struct dma_tx_state *txstate)
1237 {
1238         struct pxad_chan *chan = to_pxad_chan(dchan);
1239         enum dma_status ret;
1240
1241         if (cookie == chan->bus_error)
1242                 return DMA_ERROR;
1243
1244         ret = dma_cookie_status(dchan, cookie, txstate);
1245         if (likely(txstate && (ret != DMA_ERROR)))
1246                 dma_set_residue(txstate, pxad_residue(chan, cookie));
1247
1248         return ret;
1249 }
1250
1251 static void pxad_synchronize(struct dma_chan *dchan)
1252 {
1253         struct pxad_chan *chan = to_pxad_chan(dchan);
1254
1255         wait_event(chan->wq_state, !is_chan_running(chan));
1256         vchan_synchronize(&chan->vc);
1257 }
1258
1259 static void pxad_free_channels(struct dma_device *dmadev)
1260 {
1261         struct pxad_chan *c, *cn;
1262
1263         list_for_each_entry_safe(c, cn, &dmadev->channels,
1264                                  vc.chan.device_node) {
1265                 list_del(&c->vc.chan.device_node);
1266                 tasklet_kill(&c->vc.task);
1267         }
1268 }
1269
1270 static int pxad_remove(struct platform_device *op)
1271 {
1272         struct pxad_device *pdev = platform_get_drvdata(op);
1273
1274         pxad_cleanup_debugfs(pdev);
1275         pxad_free_channels(&pdev->slave);
1276         return 0;
1277 }
1278
1279 static int pxad_init_phys(struct platform_device *op,
1280                           struct pxad_device *pdev,
1281                           unsigned int nb_phy_chans)
1282 {
1283         int irq0, irq, nr_irq = 0, i, ret;
1284         struct pxad_phy *phy;
1285
1286         irq0 = platform_get_irq(op, 0);
1287         if (irq0 < 0)
1288                 return irq0;
1289
1290         pdev->phys = devm_kcalloc(&op->dev, nb_phy_chans,
1291                                   sizeof(pdev->phys[0]), GFP_KERNEL);
1292         if (!pdev->phys)
1293                 return -ENOMEM;
1294
1295         for (i = 0; i < nb_phy_chans; i++)
1296                 if (platform_get_irq(op, i) > 0)
1297                         nr_irq++;
1298
1299         for (i = 0; i < nb_phy_chans; i++) {
1300                 phy = &pdev->phys[i];
1301                 phy->base = pdev->base;
1302                 phy->idx = i;
1303                 irq = platform_get_irq(op, i);
1304                 if ((nr_irq > 1) && (irq > 0))
1305                         ret = devm_request_irq(&op->dev, irq,
1306                                                pxad_chan_handler,
1307                                                IRQF_SHARED, "pxa-dma", phy);
1308                 if ((nr_irq == 1) && (i == 0))
1309                         ret = devm_request_irq(&op->dev, irq0,
1310                                                pxad_int_handler,
1311                                                IRQF_SHARED, "pxa-dma", pdev);
1312                 if (ret) {
1313                         dev_err(pdev->slave.dev,
1314                                 "%s(): can't request irq %d:%d\n", __func__,
1315                                 irq, ret);
1316                         return ret;
1317                 }
1318         }
1319
1320         return 0;
1321 }
1322
1323 static const struct of_device_id pxad_dt_ids[] = {
1324         { .compatible = "marvell,pdma-1.0", },
1325         {}
1326 };
1327 MODULE_DEVICE_TABLE(of, pxad_dt_ids);
1328
1329 static struct dma_chan *pxad_dma_xlate(struct of_phandle_args *dma_spec,
1330                                            struct of_dma *ofdma)
1331 {
1332         struct pxad_device *d = ofdma->of_dma_data;
1333         struct dma_chan *chan;
1334
1335         chan = dma_get_any_slave_channel(&d->slave);
1336         if (!chan)
1337                 return NULL;
1338
1339         to_pxad_chan(chan)->drcmr = dma_spec->args[0];
1340         to_pxad_chan(chan)->prio = dma_spec->args[1];
1341
1342         return chan;
1343 }
1344
1345 static int pxad_init_dmadev(struct platform_device *op,
1346                             struct pxad_device *pdev,
1347                             unsigned int nr_phy_chans,
1348                             unsigned int nr_requestors)
1349 {
1350         int ret;
1351         unsigned int i;
1352         struct pxad_chan *c;
1353
1354         pdev->nr_chans = nr_phy_chans;
1355         pdev->nr_requestors = nr_requestors;
1356         INIT_LIST_HEAD(&pdev->slave.channels);
1357         pdev->slave.device_alloc_chan_resources = pxad_alloc_chan_resources;
1358         pdev->slave.device_free_chan_resources = pxad_free_chan_resources;
1359         pdev->slave.device_tx_status = pxad_tx_status;
1360         pdev->slave.device_issue_pending = pxad_issue_pending;
1361         pdev->slave.device_config = pxad_config;
1362         pdev->slave.device_synchronize = pxad_synchronize;
1363         pdev->slave.device_terminate_all = pxad_terminate_all;
1364
1365         if (op->dev.coherent_dma_mask)
1366                 dma_set_mask(&op->dev, op->dev.coherent_dma_mask);
1367         else
1368                 dma_set_mask(&op->dev, DMA_BIT_MASK(32));
1369
1370         ret = pxad_init_phys(op, pdev, nr_phy_chans);
1371         if (ret)
1372                 return ret;
1373
1374         for (i = 0; i < nr_phy_chans; i++) {
1375                 c = devm_kzalloc(&op->dev, sizeof(*c), GFP_KERNEL);
1376                 if (!c)
1377                         return -ENOMEM;
1378
1379                 c->drcmr = U32_MAX;
1380                 c->prio = PXAD_PRIO_LOWEST;
1381                 c->vc.desc_free = pxad_free_desc;
1382                 vchan_init(&c->vc, &pdev->slave);
1383                 init_waitqueue_head(&c->wq_state);
1384         }
1385
1386         return dmaenginem_async_device_register(&pdev->slave);
1387 }
1388
1389 static int pxad_probe(struct platform_device *op)
1390 {
1391         struct pxad_device *pdev;
1392         const struct of_device_id *of_id;
1393         const struct dma_slave_map *slave_map = NULL;
1394         struct mmp_dma_platdata *pdata = dev_get_platdata(&op->dev);
1395         struct resource *iores;
1396         int ret, dma_channels = 0, nb_requestors = 0, slave_map_cnt = 0;
1397         const enum dma_slave_buswidth widths =
1398                 DMA_SLAVE_BUSWIDTH_1_BYTE   | DMA_SLAVE_BUSWIDTH_2_BYTES |
1399                 DMA_SLAVE_BUSWIDTH_4_BYTES;
1400
1401         pdev = devm_kzalloc(&op->dev, sizeof(*pdev), GFP_KERNEL);
1402         if (!pdev)
1403                 return -ENOMEM;
1404
1405         spin_lock_init(&pdev->phy_lock);
1406
1407         iores = platform_get_resource(op, IORESOURCE_MEM, 0);
1408         pdev->base = devm_ioremap_resource(&op->dev, iores);
1409         if (IS_ERR(pdev->base))
1410                 return PTR_ERR(pdev->base);
1411
1412         of_id = of_match_device(pxad_dt_ids, &op->dev);
1413         if (of_id) {
1414                 of_property_read_u32(op->dev.of_node, "#dma-channels",
1415                                      &dma_channels);
1416                 ret = of_property_read_u32(op->dev.of_node, "#dma-requests",
1417                                            &nb_requestors);
1418                 if (ret) {
1419                         dev_warn(pdev->slave.dev,
1420                                  "#dma-requests set to default 32 as missing in OF: %d",
1421                                  ret);
1422                         nb_requestors = 32;
1423                 }
1424         } else if (pdata && pdata->dma_channels) {
1425                 dma_channels = pdata->dma_channels;
1426                 nb_requestors = pdata->nb_requestors;
1427                 slave_map = pdata->slave_map;
1428                 slave_map_cnt = pdata->slave_map_cnt;
1429         } else {
1430                 dma_channels = 32;      /* default 32 channel */
1431         }
1432
1433         dma_cap_set(DMA_SLAVE, pdev->slave.cap_mask);
1434         dma_cap_set(DMA_MEMCPY, pdev->slave.cap_mask);
1435         dma_cap_set(DMA_CYCLIC, pdev->slave.cap_mask);
1436         dma_cap_set(DMA_PRIVATE, pdev->slave.cap_mask);
1437         pdev->slave.device_prep_dma_memcpy = pxad_prep_memcpy;
1438         pdev->slave.device_prep_slave_sg = pxad_prep_slave_sg;
1439         pdev->slave.device_prep_dma_cyclic = pxad_prep_dma_cyclic;
1440         pdev->slave.filter.map = slave_map;
1441         pdev->slave.filter.mapcnt = slave_map_cnt;
1442         pdev->slave.filter.fn = pxad_filter_fn;
1443
1444         pdev->slave.copy_align = PDMA_ALIGNMENT;
1445         pdev->slave.src_addr_widths = widths;
1446         pdev->slave.dst_addr_widths = widths;
1447         pdev->slave.directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
1448         pdev->slave.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
1449         pdev->slave.descriptor_reuse = true;
1450
1451         pdev->slave.dev = &op->dev;
1452         ret = pxad_init_dmadev(op, pdev, dma_channels, nb_requestors);
1453         if (ret) {
1454                 dev_err(pdev->slave.dev, "unable to register\n");
1455                 return ret;
1456         }
1457
1458         if (op->dev.of_node) {
1459                 /* Device-tree DMA controller registration */
1460                 ret = of_dma_controller_register(op->dev.of_node,
1461                                                  pxad_dma_xlate, pdev);
1462                 if (ret < 0) {
1463                         dev_err(pdev->slave.dev,
1464                                 "of_dma_controller_register failed\n");
1465                         return ret;
1466                 }
1467         }
1468
1469         platform_set_drvdata(op, pdev);
1470         pxad_init_debugfs(pdev);
1471         dev_info(pdev->slave.dev, "initialized %d channels on %d requestors\n",
1472                  dma_channels, nb_requestors);
1473         return 0;
1474 }
1475
1476 static const struct platform_device_id pxad_id_table[] = {
1477         { "pxa-dma", },
1478         { },
1479 };
1480
1481 static struct platform_driver pxad_driver = {
1482         .driver         = {
1483                 .name   = "pxa-dma",
1484                 .of_match_table = pxad_dt_ids,
1485         },
1486         .id_table       = pxad_id_table,
1487         .probe          = pxad_probe,
1488         .remove         = pxad_remove,
1489 };
1490
1491 static bool pxad_filter_fn(struct dma_chan *chan, void *param)
1492 {
1493         struct pxad_chan *c = to_pxad_chan(chan);
1494         struct pxad_param *p = param;
1495
1496         if (chan->device->dev->driver != &pxad_driver.driver)
1497                 return false;
1498
1499         c->drcmr = p->drcmr;
1500         c->prio = p->prio;
1501
1502         return true;
1503 }
1504
1505 module_platform_driver(pxad_driver);
1506
1507 MODULE_DESCRIPTION("Marvell PXA Peripheral DMA Driver");
1508 MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
1509 MODULE_LICENSE("GPL v2");