drivers/dma/pxa_dma.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright 2015 Robert Jarzmik <robert.jarzmik@free.fr>
   4  */
   5
   6 #include <linux/err.h>
   7 #include <linux/module.h>
   8 #include <linux/init.h>
   9 #include <linux/types.h>
  10 #include <linux/interrupt.h>
  11 #include <linux/dma-mapping.h>
  12 #include <linux/slab.h>
  13 #include <linux/dmaengine.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/device.h>
  16 #include <linux/platform_data/mmp_dma.h>
  17 #include <linux/dmapool.h>
  18 #include <linux/of_device.h>
  19 #include <linux/of_dma.h>
  20 #include <linux/of.h>
  21 #include <linux/wait.h>
  22 #include <linux/dma/pxa-dma.h>
  23
  24 #include "dmaengine.h"
  25 #include "virt-dma.h"
  26
  27 #define DCSR(n)         (0x0000 + ((n) << 2))
  28 #define DALGN(n)        0x00a0
  29 #define DINT            0x00f0
  30 #define DDADR(n)        (0x0200 + ((n) << 4))
  31 #define DSADR(n)        (0x0204 + ((n) << 4))
  32 #define DTADR(n)        (0x0208 + ((n) << 4))
  33 #define DCMD(n)         (0x020c + ((n) << 4))
  34
  35 #define PXA_DCSR_RUN            BIT(31) /* Run Bit (read / write) */
  36 #define PXA_DCSR_NODESC         BIT(30) /* No-Descriptor Fetch (read / write) */
  37 #define PXA_DCSR_STOPIRQEN      BIT(29) /* Stop Interrupt Enable (R/W) */
  38 #define PXA_DCSR_REQPEND        BIT(8)  /* Request Pending (read-only) */
  39 #define PXA_DCSR_STOPSTATE      BIT(3)  /* Stop State (read-only) */
  40 #define PXA_DCSR_ENDINTR        BIT(2)  /* End Interrupt (read / write) */
  41 #define PXA_DCSR_STARTINTR      BIT(1)  /* Start Interrupt (read / write) */
  42 #define PXA_DCSR_BUSERR         BIT(0)  /* Bus Error Interrupt (read / write) */
  43
  44 #define PXA_DCSR_EORIRQEN       BIT(28) /* End of Receive IRQ Enable (R/W) */
  45 #define PXA_DCSR_EORJMPEN       BIT(27) /* Jump to next descriptor on EOR */
  46 #define PXA_DCSR_EORSTOPEN      BIT(26) /* STOP on an EOR */
  47 #define PXA_DCSR_SETCMPST       BIT(25) /* Set Descriptor Compare Status */
  48 #define PXA_DCSR_CLRCMPST       BIT(24) /* Clear Descriptor Compare Status */
  49 #define PXA_DCSR_CMPST          BIT(10) /* The Descriptor Compare Status */
  50 #define PXA_DCSR_EORINTR        BIT(9)  /* The end of Receive */
  51
  52 #define DRCMR_MAPVLD    BIT(7)  /* Map Valid (read / write) */
  53 #define DRCMR_CHLNUM    0x1f    /* mask for Channel Number (read / write) */
  54
  55 #define DDADR_DESCADDR  0xfffffff0      /* Address of next descriptor (mask) */
  56 #define DDADR_STOP      BIT(0)  /* Stop (read / write) */
  57
  58 #define PXA_DCMD_INCSRCADDR     BIT(31) /* Source Address Increment Setting. */
  59 #define PXA_DCMD_INCTRGADDR     BIT(30) /* Target Address Increment Setting. */
  60 #define PXA_DCMD_FLOWSRC        BIT(29) /* Flow Control by the source. */
  61 #define PXA_DCMD_FLOWTRG        BIT(28) /* Flow Control by the target. */
  62 #define PXA_DCMD_STARTIRQEN     BIT(22) /* Start Interrupt Enable */
  63 #define PXA_DCMD_ENDIRQEN       BIT(21) /* End Interrupt Enable */
  64 #define PXA_DCMD_ENDIAN         BIT(18) /* Device Endian-ness. */
  65 #define PXA_DCMD_BURST8         (1 << 16)       /* 8 byte burst */
  66 #define PXA_DCMD_BURST16        (2 << 16)       /* 16 byte burst */
  67 #define PXA_DCMD_BURST32        (3 << 16)       /* 32 byte burst */
  68 #define PXA_DCMD_WIDTH1         (1 << 14)       /* 1 byte width */
  69 #define PXA_DCMD_WIDTH2         (2 << 14)       /* 2 byte width (HalfWord) */
  70 #define PXA_DCMD_WIDTH4         (3 << 14)       /* 4 byte width (Word) */
  71 #define PXA_DCMD_LENGTH         0x01fff         /* length mask (max = 8K - 1) */
  72
  73 #define PDMA_ALIGNMENT          3
  74 #define PDMA_MAX_DESC_BYTES     (PXA_DCMD_LENGTH & ~((1 << PDMA_ALIGNMENT) - 1))
  75
  76 struct pxad_desc_hw {
  77         u32 ddadr;      /* Points to the next descriptor + flags */
  78         u32 dsadr;      /* DSADR value for the current transfer */
  79         u32 dtadr;      /* DTADR value for the current transfer */
  80         u32 dcmd;       /* DCMD value for the current transfer */
  81 } __aligned(16);
  82
  83 struct pxad_desc_sw {
  84         struct virt_dma_desc    vd;             /* Virtual descriptor */
  85         int                     nb_desc;        /* Number of hw. descriptors */
  86         size_t                  len;            /* Number of bytes xfered */
  87         dma_addr_t              first;          /* First descriptor's addr */
  88
  89         /* At least one descriptor has an src/dst address not multiple of 8 */
  90         bool                    misaligned;
  91         bool                    cyclic;
  92         struct dma_pool         *desc_pool;     /* Channel's used allocator */
  93
  94         struct pxad_desc_hw     *hw_desc[];     /* DMA coherent descriptors */
  95 };
  96
  97 struct pxad_phy {
  98         int                     idx;
  99         void __iomem            *base;
 100         struct pxad_chan        *vchan;
 101 };
 102
 103 struct pxad_chan {
 104         struct virt_dma_chan    vc;             /* Virtual channel */
 105         u32                     drcmr;          /* Requestor of the channel */
 106         enum pxad_chan_prio     prio;           /* Required priority of phy */
 107         /*
 108          * At least one desc_sw in submitted or issued transfers on this channel
 109          * has one address such as: addr % 8 != 0. This implies the DALGN
 110          * setting on the phy.
 111          */
 112         bool                    misaligned;
 113         struct dma_slave_config cfg;            /* Runtime config */
 114
 115         /* protected by vc->lock */
 116         struct pxad_phy         *phy;
 117         struct dma_pool         *desc_pool;     /* Descriptors pool */
 118         dma_cookie_t            bus_error;
 119
 120         wait_queue_head_t       wq_state;
 121 };
 122
 123 struct pxad_device {
 124         struct dma_device               slave;
 125         int                             nr_chans;
 126         int                             nr_requestors;
 127         void __iomem                    *base;
 128         struct pxad_phy                 *phys;
 129         spinlock_t                      phy_lock;       /* Phy association */
 130 #ifdef CONFIG_DEBUG_FS
 131         struct dentry                   *dbgfs_root;
 132         struct dentry                   **dbgfs_chan;
 133 #endif
 134 };
 135
 136 #define tx_to_pxad_desc(tx)                                     \
 137         container_of(tx, struct pxad_desc_sw, async_tx)
 138 #define to_pxad_chan(dchan)                                     \
 139         container_of(dchan, struct pxad_chan, vc.chan)
 140 #define to_pxad_dev(dmadev)                                     \
 141         container_of(dmadev, struct pxad_device, slave)
 142 #define to_pxad_sw_desc(_vd)                            \
 143         container_of((_vd), struct pxad_desc_sw, vd)
 144
 145 #define _phy_readl_relaxed(phy, _reg)                                   \
 146         readl_relaxed((phy)->base + _reg((phy)->idx))
 147 #define phy_readl_relaxed(phy, _reg)                                    \
 148         ({                                                              \
 149                 u32 _v;                                                 \
 150                 _v = readl_relaxed((phy)->base + _reg((phy)->idx));     \
 151                 dev_vdbg(&phy->vchan->vc.chan.dev->device,              \
 152                          "%s(): readl(%s): 0x%08x\n", __func__, #_reg,  \
 153                           _v);                                          \
 154                 _v;                                                     \
 155         })
 156 #define phy_writel(phy, val, _reg)                                      \
 157         do {                                                            \
 158                 writel((val), (phy)->base + _reg((phy)->idx));          \
 159                 dev_vdbg(&phy->vchan->vc.chan.dev->device,              \
 160                          "%s(): writel(0x%08x, %s)\n",                  \
 161                          __func__, (u32)(val), #_reg);                  \
 162         } while (0)
 163 #define phy_writel_relaxed(phy, val, _reg)                              \
 164         do {                                                            \
 165                 writel_relaxed((val), (phy)->base + _reg((phy)->idx));  \
 166                 dev_vdbg(&phy->vchan->vc.chan.dev->device,              \
 167                          "%s(): writel_relaxed(0x%08x, %s)\n",          \
 168                          __func__, (u32)(val), #_reg);                  \
 169         } while (0)
 170
 171 static unsigned int pxad_drcmr(unsigned int line)
 172 {
 173         if (line < 64)
 174                 return 0x100 + line * 4;
 175         return 0x1000 + line * 4;
 176 }
 177
 178 static bool pxad_filter_fn(struct dma_chan *chan, void *param);
 179
 180 /*
 181  * Debug fs
 182  */
 183 #ifdef CONFIG_DEBUG_FS
 184 #include <linux/debugfs.h>
 185 #include <linux/uaccess.h>
 186 #include <linux/seq_file.h>
 187
 188 static int requester_chan_show(struct seq_file *s, void *p)
 189 {
 190         struct pxad_phy *phy = s->private;
 191         int i;
 192         u32 drcmr;
 193
 194         seq_printf(s, "DMA channel %d requester :\n", phy->idx);
 195         for (i = 0; i < 70; i++) {
 196                 drcmr = readl_relaxed(phy->base + pxad_drcmr(i));
 197                 if ((drcmr & DRCMR_CHLNUM) == phy->idx)
 198                         seq_printf(s, "\tRequester %d (MAPVLD=%d)\n", i,
 199                                    !!(drcmr & DRCMR_MAPVLD));
 200         }
 201         return 0;
 202 }
 203
 204 static inline int dbg_burst_from_dcmd(u32 dcmd)
 205 {
 206         int burst = (dcmd >> 16) & 0x3;
 207
 208         return burst ? 4 << burst : 0;
 209 }
 210
 211 static int is_phys_valid(unsigned long addr)
 212 {
 213         return pfn_valid(__phys_to_pfn(addr));
 214 }
 215
 216 #define PXA_DCSR_STR(flag) (dcsr & PXA_DCSR_##flag ? #flag" " : "")
 217 #define PXA_DCMD_STR(flag) (dcmd & PXA_DCMD_##flag ? #flag" " : "")
 218
 219 static int descriptors_show(struct seq_file *s, void *p)
 220 {
 221         struct pxad_phy *phy = s->private;
 222         int i, max_show = 20, burst, width;
 223         u32 dcmd;
 224         unsigned long phys_desc, ddadr;
 225         struct pxad_desc_hw *desc;
 226
 227         phys_desc = ddadr = _phy_readl_relaxed(phy, DDADR);
 228
 229         seq_printf(s, "DMA channel %d descriptors :\n", phy->idx);
 230         seq_printf(s, "[%03d] First descriptor unknown\n", 0);
 231         for (i = 1; i < max_show && is_phys_valid(phys_desc); i++) {
 232                 desc = phys_to_virt(phys_desc);
 233                 dcmd = desc->dcmd;
 234                 burst = dbg_burst_from_dcmd(dcmd);
 235                 width = (1 << ((dcmd >> 14) & 0x3)) >> 1;
 236
 237                 seq_printf(s, "[%03d] Desc at %08lx(virt %p)\n",
 238                            i, phys_desc, desc);
 239                 seq_printf(s, "\tDDADR = %08x\n", desc->ddadr);
 240                 seq_printf(s, "\tDSADR = %08x\n", desc->dsadr);
 241                 seq_printf(s, "\tDTADR = %08x\n", desc->dtadr);
 242                 seq_printf(s, "\tDCMD  = %08x (%s%s%s%s%s%s%sburst=%d width=%d len=%d)\n",
 243                            dcmd,
 244                            PXA_DCMD_STR(INCSRCADDR), PXA_DCMD_STR(INCTRGADDR),
 245                            PXA_DCMD_STR(FLOWSRC), PXA_DCMD_STR(FLOWTRG),
 246                            PXA_DCMD_STR(STARTIRQEN), PXA_DCMD_STR(ENDIRQEN),
 247                            PXA_DCMD_STR(ENDIAN), burst, width,
 248                            dcmd & PXA_DCMD_LENGTH);
 249                 phys_desc = desc->ddadr;
 250         }
 251         if (i == max_show)
 252                 seq_printf(s, "[%03d] Desc at %08lx ... max display reached\n",
 253                            i, phys_desc);
 254         else
 255                 seq_printf(s, "[%03d] Desc at %08lx is %s\n",
 256                            i, phys_desc, phys_desc == DDADR_STOP ?
 257                            "DDADR_STOP" : "invalid");
 258
 259         return 0;
 260 }
 261
 262 static int chan_state_show(struct seq_file *s, void *p)
 263 {
 264         struct pxad_phy *phy = s->private;
 265         u32 dcsr, dcmd;
 266         int burst, width;
 267         static const char * const str_prio[] = {
 268                 "high", "normal", "low", "invalid"
 269         };
 270
 271         dcsr = _phy_readl_relaxed(phy, DCSR);
 272         dcmd = _phy_readl_relaxed(phy, DCMD);
 273         burst = dbg_burst_from_dcmd(dcmd);
 274         width = (1 << ((dcmd >> 14) & 0x3)) >> 1;
 275
 276         seq_printf(s, "DMA channel %d\n", phy->idx);
 277         seq_printf(s, "\tPriority : %s\n",
 278                           str_prio[(phy->idx & 0xf) / 4]);
 279         seq_printf(s, "\tUnaligned transfer bit: %s\n",
 280                           _phy_readl_relaxed(phy, DALGN) & BIT(phy->idx) ?
 281                           "yes" : "no");
 282         seq_printf(s, "\tDCSR  = %08x (%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s)\n",
 283                    dcsr, PXA_DCSR_STR(RUN), PXA_DCSR_STR(NODESC),
 284                    PXA_DCSR_STR(STOPIRQEN), PXA_DCSR_STR(EORIRQEN),
 285                    PXA_DCSR_STR(EORJMPEN), PXA_DCSR_STR(EORSTOPEN),
 286                    PXA_DCSR_STR(SETCMPST), PXA_DCSR_STR(CLRCMPST),
 287                    PXA_DCSR_STR(CMPST), PXA_DCSR_STR(EORINTR),
 288                    PXA_DCSR_STR(REQPEND), PXA_DCSR_STR(STOPSTATE),
 289                    PXA_DCSR_STR(ENDINTR), PXA_DCSR_STR(STARTINTR),
 290                    PXA_DCSR_STR(BUSERR));
 291
 292         seq_printf(s, "\tDCMD  = %08x (%s%s%s%s%s%s%sburst=%d width=%d len=%d)\n",
 293                    dcmd,
 294                    PXA_DCMD_STR(INCSRCADDR), PXA_DCMD_STR(INCTRGADDR),
 295                    PXA_DCMD_STR(FLOWSRC), PXA_DCMD_STR(FLOWTRG),
 296                    PXA_DCMD_STR(STARTIRQEN), PXA_DCMD_STR(ENDIRQEN),
 297                    PXA_DCMD_STR(ENDIAN), burst, width, dcmd & PXA_DCMD_LENGTH);
 298         seq_printf(s, "\tDSADR = %08x\n", _phy_readl_relaxed(phy, DSADR));
 299         seq_printf(s, "\tDTADR = %08x\n", _phy_readl_relaxed(phy, DTADR));
 300         seq_printf(s, "\tDDADR = %08x\n", _phy_readl_relaxed(phy, DDADR));
 301
 302         return 0;
 303 }
 304
 305 static int state_show(struct seq_file *s, void *p)
 306 {
 307         struct pxad_device *pdev = s->private;
 308
 309         /* basic device status */
 310         seq_puts(s, "DMA engine status\n");
 311         seq_printf(s, "\tChannel number: %d\n", pdev->nr_chans);
 312
 313         return 0;
 314 }
 315
 316 DEFINE_SHOW_ATTRIBUTE(state);
 317 DEFINE_SHOW_ATTRIBUTE(chan_state);
 318 DEFINE_SHOW_ATTRIBUTE(descriptors);
 319 DEFINE_SHOW_ATTRIBUTE(requester_chan);
 320
 321 static struct dentry *pxad_dbg_alloc_chan(struct pxad_device *pdev,
 322                                              int ch, struct dentry *chandir)
 323 {
 324         char chan_name[11];
 325         struct dentry *chan;
 326         void *dt;
 327
 328         scnprintf(chan_name, sizeof(chan_name), "%d", ch);
 329         chan = debugfs_create_dir(chan_name, chandir);
 330         dt = (void *)&pdev->phys[ch];
 331
 332         debugfs_create_file("state", 0400, chan, dt, &chan_state_fops);
 333         debugfs_create_file("descriptors", 0400, chan, dt, &descriptors_fops);
 334         debugfs_create_file("requesters", 0400, chan, dt, &requester_chan_fops);
 335
 336         return chan;
 337 }
 338
 339 static void pxad_init_debugfs(struct pxad_device *pdev)
 340 {
 341         int i;
 342         struct dentry *chandir;
 343
 344         pdev->dbgfs_chan =
 345                 kmalloc_array(pdev->nr_chans, sizeof(struct dentry *),
 346                               GFP_KERNEL);
 347         if (!pdev->dbgfs_chan)
 348                 return;
 349
 350         pdev->dbgfs_root = debugfs_create_dir(dev_name(pdev->slave.dev), NULL);
 351
 352         debugfs_create_file("state", 0400, pdev->dbgfs_root, pdev, &state_fops);
 353
 354         chandir = debugfs_create_dir("channels", pdev->dbgfs_root);
 355
 356         for (i = 0; i < pdev->nr_chans; i++)
 357                 pdev->dbgfs_chan[i] = pxad_dbg_alloc_chan(pdev, i, chandir);
 358 }
 359
 360 static void pxad_cleanup_debugfs(struct pxad_device *pdev)
 361 {
 362         debugfs_remove_recursive(pdev->dbgfs_root);
 363 }
 364 #else
 365 static inline void pxad_init_debugfs(struct pxad_device *pdev) {}
 366 static inline void pxad_cleanup_debugfs(struct pxad_device *pdev) {}
 367 #endif
 368
 369 static struct pxad_phy *lookup_phy(struct pxad_chan *pchan)
 370 {
 371         int prio, i;
 372         struct pxad_device *pdev = to_pxad_dev(pchan->vc.chan.device);
 373         struct pxad_phy *phy, *found = NULL;
 374         unsigned long flags;
 375
 376         /*
 377          * dma channel priorities
 378          * ch 0 - 3,  16 - 19  <--> (0)
 379          * ch 4 - 7,  20 - 23  <--> (1)
 380          * ch 8 - 11, 24 - 27  <--> (2)
 381          * ch 12 - 15, 28 - 31  <--> (3)
 382          */
 383
 384         spin_lock_irqsave(&pdev->phy_lock, flags);
 385         for (prio = pchan->prio; prio >= PXAD_PRIO_HIGHEST; prio--) {
 386                 for (i = 0; i < pdev->nr_chans; i++) {
 387                         if (prio != (i & 0xf) >> 2)
 388                                 continue;
 389                         phy = &pdev->phys[i];
 390                         if (!phy->vchan) {
 391                                 phy->vchan = pchan;
 392                                 found = phy;
 393                                 goto out_unlock;
 394                         }
 395                 }
 396         }
 397
 398 out_unlock:
 399         spin_unlock_irqrestore(&pdev->phy_lock, flags);
 400         dev_dbg(&pchan->vc.chan.dev->device,
 401                 "%s(): phy=%p(%d)\n", __func__, found,
 402                 found ? found->idx : -1);
 403
 404         return found;
 405 }
 406
 407 static void pxad_free_phy(struct pxad_chan *chan)
 408 {
 409         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
 410         unsigned long flags;
 411         u32 reg;
 412
 413         dev_dbg(&chan->vc.chan.dev->device,
 414                 "%s(): freeing\n", __func__);
 415         if (!chan->phy)
 416                 return;
 417
 418         /* clear the channel mapping in DRCMR */
 419         if (chan->drcmr <= pdev->nr_requestors) {
 420                 reg = pxad_drcmr(chan->drcmr);
 421                 writel_relaxed(0, chan->phy->base + reg);
 422         }
 423
 424         spin_lock_irqsave(&pdev->phy_lock, flags);
 425         chan->phy->vchan = NULL;
 426         chan->phy = NULL;
 427         spin_unlock_irqrestore(&pdev->phy_lock, flags);
 428 }
 429
 430 static bool is_chan_running(struct pxad_chan *chan)
 431 {
 432         u32 dcsr;
 433         struct pxad_phy *phy = chan->phy;
 434
 435         if (!phy)
 436                 return false;
 437         dcsr = phy_readl_relaxed(phy, DCSR);
 438         return dcsr & PXA_DCSR_RUN;
 439 }
 440
 441 static bool is_running_chan_misaligned(struct pxad_chan *chan)
 442 {
 443         u32 dalgn;
 444
 445         BUG_ON(!chan->phy);
 446         dalgn = phy_readl_relaxed(chan->phy, DALGN);
 447         return dalgn & (BIT(chan->phy->idx));
 448 }
 449
 450 static void phy_enable(struct pxad_phy *phy, bool misaligned)
 451 {
 452         struct pxad_device *pdev;
 453         u32 reg, dalgn;
 454
 455         if (!phy->vchan)
 456                 return;
 457
 458         dev_dbg(&phy->vchan->vc.chan.dev->device,
 459                 "%s(); phy=%p(%d) misaligned=%d\n", __func__,
 460                 phy, phy->idx, misaligned);
 461
 462         pdev = to_pxad_dev(phy->vchan->vc.chan.device);
 463         if (phy->vchan->drcmr <= pdev->nr_requestors) {
 464                 reg = pxad_drcmr(phy->vchan->drcmr);
 465                 writel_relaxed(DRCMR_MAPVLD | phy->idx, phy->base + reg);
 466         }
 467
 468         dalgn = phy_readl_relaxed(phy, DALGN);
 469         if (misaligned)
 470                 dalgn |= BIT(phy->idx);
 471         else
 472                 dalgn &= ~BIT(phy->idx);
 473         phy_writel_relaxed(phy, dalgn, DALGN);
 474
 475         phy_writel(phy, PXA_DCSR_STOPIRQEN | PXA_DCSR_ENDINTR |
 476                    PXA_DCSR_BUSERR | PXA_DCSR_RUN, DCSR);
 477 }
 478
 479 static void phy_disable(struct pxad_phy *phy)
 480 {
 481         u32 dcsr;
 482
 483         if (!phy)
 484                 return;
 485
 486         dcsr = phy_readl_relaxed(phy, DCSR);
 487         dev_dbg(&phy->vchan->vc.chan.dev->device,
 488                 "%s(): phy=%p(%d)\n", __func__, phy, phy->idx);
 489         phy_writel(phy, dcsr & ~PXA_DCSR_RUN & ~PXA_DCSR_STOPIRQEN, DCSR);
 490 }
 491
 492 static void pxad_launch_chan(struct pxad_chan *chan,
 493                                  struct pxad_desc_sw *desc)
 494 {
 495         dev_dbg(&chan->vc.chan.dev->device,
 496                 "%s(): desc=%p\n", __func__, desc);
 497         if (!chan->phy) {
 498                 chan->phy = lookup_phy(chan);
 499                 if (!chan->phy) {
 500                         dev_dbg(&chan->vc.chan.dev->device,
 501                                 "%s(): no free dma channel\n", __func__);
 502                         return;
 503                 }
 504         }
 505         chan->bus_error = 0;
 506
 507         /*
 508          * Program the descriptor's address into the DMA controller,
 509          * then start the DMA transaction
 510          */
 511         phy_writel(chan->phy, desc->first, DDADR);
 512         phy_enable(chan->phy, chan->misaligned);
 513         wake_up(&chan->wq_state);
 514 }
 515
 516 static void set_updater_desc(struct pxad_desc_sw *sw_desc,
 517                              unsigned long flags)
 518 {
 519         struct pxad_desc_hw *updater =
 520                 sw_desc->hw_desc[sw_desc->nb_desc - 1];
 521         dma_addr_t dma = sw_desc->hw_desc[sw_desc->nb_desc - 2]->ddadr;
 522
 523         updater->ddadr = DDADR_STOP;
 524         updater->dsadr = dma;
 525         updater->dtadr = dma + 8;
 526         updater->dcmd = PXA_DCMD_WIDTH4 | PXA_DCMD_BURST32 |
 527                 (PXA_DCMD_LENGTH & sizeof(u32));
 528         if (flags & DMA_PREP_INTERRUPT)
 529                 updater->dcmd |= PXA_DCMD_ENDIRQEN;
 530         if (sw_desc->cyclic)
 531                 sw_desc->hw_desc[sw_desc->nb_desc - 2]->ddadr = sw_desc->first;
 532 }
 533
 534 static bool is_desc_completed(struct virt_dma_desc *vd)
 535 {
 536         struct pxad_desc_sw *sw_desc = to_pxad_sw_desc(vd);
 537         struct pxad_desc_hw *updater =
 538                 sw_desc->hw_desc[sw_desc->nb_desc - 1];
 539
 540         return updater->dtadr != (updater->dsadr + 8);
 541 }
 542
 543 static void pxad_desc_chain(struct virt_dma_desc *vd1,
 544                                 struct virt_dma_desc *vd2)
 545 {
 546         struct pxad_desc_sw *desc1 = to_pxad_sw_desc(vd1);
 547         struct pxad_desc_sw *desc2 = to_pxad_sw_desc(vd2);
 548         dma_addr_t dma_to_chain;
 549
 550         dma_to_chain = desc2->first;
 551         desc1->hw_desc[desc1->nb_desc - 1]->ddadr = dma_to_chain;
 552 }
 553
 554 static bool pxad_try_hotchain(struct virt_dma_chan *vc,
 555                                   struct virt_dma_desc *vd)
 556 {
 557         struct virt_dma_desc *vd_last_issued = NULL;
 558         struct pxad_chan *chan = to_pxad_chan(&vc->chan);
 559
 560         /*
 561          * Attempt to hot chain the tx if the phy is still running. This is
 562          * considered successful only if either the channel is still running
 563          * after the chaining, or if the chained transfer is completed after
 564          * having been hot chained.
 565          * A change of alignment is not allowed, and forbids hotchaining.
 566          */
 567         if (is_chan_running(chan)) {
 568                 BUG_ON(list_empty(&vc->desc_issued));
 569
 570                 if (!is_running_chan_misaligned(chan) &&
 571                     to_pxad_sw_desc(vd)->misaligned)
 572                         return false;
 573
 574                 vd_last_issued = list_entry(vc->desc_issued.prev,
 575                                             struct virt_dma_desc, node);
 576                 pxad_desc_chain(vd_last_issued, vd);
 577                 if (is_chan_running(chan) || is_desc_completed(vd))
 578                         return true;
 579         }
 580
 581         return false;
 582 }
 583
 584 static unsigned int clear_chan_irq(struct pxad_phy *phy)
 585 {
 586         u32 dcsr;
 587         u32 dint = readl(phy->base + DINT);
 588
 589         if (!(dint & BIT(phy->idx)))
 590                 return PXA_DCSR_RUN;
 591
 592         /* clear irq */
 593         dcsr = phy_readl_relaxed(phy, DCSR);
 594         phy_writel(phy, dcsr, DCSR);
 595         if ((dcsr & PXA_DCSR_BUSERR) && (phy->vchan))
 596                 dev_warn(&phy->vchan->vc.chan.dev->device,
 597                          "%s(chan=%p): PXA_DCSR_BUSERR\n",
 598                          __func__, &phy->vchan);
 599
 600         return dcsr & ~PXA_DCSR_RUN;
 601 }
 602
 603 static irqreturn_t pxad_chan_handler(int irq, void *dev_id)
 604 {
 605         struct pxad_phy *phy = dev_id;
 606         struct pxad_chan *chan = phy->vchan;
 607         struct virt_dma_desc *vd, *tmp;
 608         unsigned int dcsr;
 609         bool vd_completed;
 610         dma_cookie_t last_started = 0;
 611
 612         BUG_ON(!chan);
 613
 614         dcsr = clear_chan_irq(phy);
 615         if (dcsr & PXA_DCSR_RUN)
 616                 return IRQ_NONE;
 617
 618         spin_lock(&chan->vc.lock);
 619         list_for_each_entry_safe(vd, tmp, &chan->vc.desc_issued, node) {
 620                 vd_completed = is_desc_completed(vd);
 621                 dev_dbg(&chan->vc.chan.dev->device,
 622                         "%s(): checking txd %p[%x]: completed=%d dcsr=0x%x\n",
 623                         __func__, vd, vd->tx.cookie, vd_completed,
 624                         dcsr);
 625                 last_started = vd->tx.cookie;
 626                 if (to_pxad_sw_desc(vd)->cyclic) {
 627                         vchan_cyclic_callback(vd);
 628                         break;
 629                 }
 630                 if (vd_completed) {
 631                         list_del(&vd->node);
 632                         vchan_cookie_complete(vd);
 633                 } else {
 634                         break;
 635                 }
 636         }
 637
 638         if (dcsr & PXA_DCSR_BUSERR) {
 639                 chan->bus_error = last_started;
 640                 phy_disable(phy);
 641         }
 642
 643         if (!chan->bus_error && dcsr & PXA_DCSR_STOPSTATE) {
 644                 dev_dbg(&chan->vc.chan.dev->device,
 645                 "%s(): channel stopped, submitted_empty=%d issued_empty=%d",
 646                         __func__,
 647                         list_empty(&chan->vc.desc_submitted),
 648                         list_empty(&chan->vc.desc_issued));
 649                 phy_writel_relaxed(phy, dcsr & ~PXA_DCSR_STOPIRQEN, DCSR);
 650
 651                 if (list_empty(&chan->vc.desc_issued)) {
 652                         chan->misaligned =
 653                                 !list_empty(&chan->vc.desc_submitted);
 654                 } else {
 655                         vd = list_first_entry(&chan->vc.desc_issued,
 656                                               struct virt_dma_desc, node);
 657                         pxad_launch_chan(chan, to_pxad_sw_desc(vd));
 658                 }
 659         }
 660         spin_unlock(&chan->vc.lock);
 661         wake_up(&chan->wq_state);
 662
 663         return IRQ_HANDLED;
 664 }
 665
 666 static irqreturn_t pxad_int_handler(int irq, void *dev_id)
 667 {
 668         struct pxad_device *pdev = dev_id;
 669         struct pxad_phy *phy;
 670         u32 dint = readl(pdev->base + DINT);
 671         int i, ret = IRQ_NONE;
 672
 673         while (dint) {
 674                 i = __ffs(dint);
 675                 dint &= (dint - 1);
 676                 phy = &pdev->phys[i];
 677                 if (pxad_chan_handler(irq, phy) == IRQ_HANDLED)
 678                         ret = IRQ_HANDLED;
 679         }
 680
 681         return ret;
 682 }
 683
 684 static int pxad_alloc_chan_resources(struct dma_chan *dchan)
 685 {
 686         struct pxad_chan *chan = to_pxad_chan(dchan);
 687         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
 688
 689         if (chan->desc_pool)
 690                 return 1;
 691
 692         chan->desc_pool = dma_pool_create(dma_chan_name(dchan),
 693                                           pdev->slave.dev,
 694                                           sizeof(struct pxad_desc_hw),
 695                                           __alignof__(struct pxad_desc_hw),
 696                                           0);
 697         if (!chan->desc_pool) {
 698                 dev_err(&chan->vc.chan.dev->device,
 699                         "%s(): unable to allocate descriptor pool\n",
 700                         __func__);
 701                 return -ENOMEM;
 702         }
 703
 704         return 1;
 705 }
 706
 707 static void pxad_free_chan_resources(struct dma_chan *dchan)
 708 {
 709         struct pxad_chan *chan = to_pxad_chan(dchan);
 710
 711         vchan_free_chan_resources(&chan->vc);
 712         dma_pool_destroy(chan->desc_pool);
 713         chan->desc_pool = NULL;
 714
 715         chan->drcmr = U32_MAX;
 716         chan->prio = PXAD_PRIO_LOWEST;
 717 }
 718
 719 static void pxad_free_desc(struct virt_dma_desc *vd)
 720 {
 721         int i;
 722         dma_addr_t dma;
 723         struct pxad_desc_sw *sw_desc = to_pxad_sw_desc(vd);
 724
 725         BUG_ON(sw_desc->nb_desc == 0);
 726         for (i = sw_desc->nb_desc - 1; i >= 0; i--) {
 727                 if (i > 0)
 728                         dma = sw_desc->hw_desc[i - 1]->ddadr;
 729                 else
 730                         dma = sw_desc->first;
 731                 dma_pool_free(sw_desc->desc_pool,
 732                               sw_desc->hw_desc[i], dma);
 733         }
 734         sw_desc->nb_desc = 0;
 735         kfree(sw_desc);
 736 }
 737
 738 static struct pxad_desc_sw *
 739 pxad_alloc_desc(struct pxad_chan *chan, unsigned int nb_hw_desc)
 740 {
 741         struct pxad_desc_sw *sw_desc;
 742         dma_addr_t dma;
 743         int i;
 744
 745         sw_desc = kzalloc(sizeof(*sw_desc) +
 746                           nb_hw_desc * sizeof(struct pxad_desc_hw *),
 747                           GFP_NOWAIT);
 748         if (!sw_desc)
 749                 return NULL;
 750         sw_desc->desc_pool = chan->desc_pool;
 751
 752         for (i = 0; i < nb_hw_desc; i++) {
 753                 sw_desc->hw_desc[i] = dma_pool_alloc(sw_desc->desc_pool,
 754                                                      GFP_NOWAIT, &dma);
 755                 if (!sw_desc->hw_desc[i]) {
 756                         dev_err(&chan->vc.chan.dev->device,
 757                                 "%s(): Couldn't allocate the %dth hw_desc from dma_pool %p\n",
 758                                 __func__, i, sw_desc->desc_pool);
 759                         goto err;
 760                 }
 761
 762                 if (i == 0)
 763                         sw_desc->first = dma;
 764                 else
 765                         sw_desc->hw_desc[i - 1]->ddadr = dma;
 766                 sw_desc->nb_desc++;
 767         }
 768
 769         return sw_desc;
 770 err:
 771         pxad_free_desc(&sw_desc->vd);
 772         return NULL;
 773 }
 774
 775 static dma_cookie_t pxad_tx_submit(struct dma_async_tx_descriptor *tx)
 776 {
 777         struct virt_dma_chan *vc = to_virt_chan(tx->chan);
 778         struct pxad_chan *chan = to_pxad_chan(&vc->chan);
 779         struct virt_dma_desc *vd_chained = NULL,
 780                 *vd = container_of(tx, struct virt_dma_desc, tx);
 781         dma_cookie_t cookie;
 782         unsigned long flags;
 783
 784         set_updater_desc(to_pxad_sw_desc(vd), tx->flags);
 785
 786         spin_lock_irqsave(&vc->lock, flags);
 787         cookie = dma_cookie_assign(tx);
 788
 789         if (list_empty(&vc->desc_submitted) && pxad_try_hotchain(vc, vd)) {
 790                 list_move_tail(&vd->node, &vc->desc_issued);
 791                 dev_dbg(&chan->vc.chan.dev->device,
 792                         "%s(): txd %p[%x]: submitted (hot linked)\n",
 793                         __func__, vd, cookie);
 794                 goto out;
 795         }
 796
 797         /*
 798          * Fallback to placing the tx in the submitted queue
 799          */
 800         if (!list_empty(&vc->desc_submitted)) {
 801                 vd_chained = list_entry(vc->desc_submitted.prev,
 802                                         struct virt_dma_desc, node);
 803                 /*
 804                  * Only chain the descriptors if no new misalignment is
 805                  * introduced. If a new misalignment is chained, let the channel
 806                  * stop, and be relaunched in misalign mode from the irq
 807                  * handler.
 808                  */
 809                 if (chan->misaligned || !to_pxad_sw_desc(vd)->misaligned)
 810                         pxad_desc_chain(vd_chained, vd);
 811                 else
 812                         vd_chained = NULL;
 813         }
 814         dev_dbg(&chan->vc.chan.dev->device,
 815                 "%s(): txd %p[%x]: submitted (%s linked)\n",
 816                 __func__, vd, cookie, vd_chained ? "cold" : "not");
 817         list_move_tail(&vd->node, &vc->desc_submitted);
 818         chan->misaligned |= to_pxad_sw_desc(vd)->misaligned;
 819
 820 out:
 821         spin_unlock_irqrestore(&vc->lock, flags);
 822         return cookie;
 823 }
 824
 825 static void pxad_issue_pending(struct dma_chan *dchan)
 826 {
 827         struct pxad_chan *chan = to_pxad_chan(dchan);
 828         struct virt_dma_desc *vd_first;
 829         unsigned long flags;
 830
 831         spin_lock_irqsave(&chan->vc.lock, flags);
 832         if (list_empty(&chan->vc.desc_submitted))
 833                 goto out;
 834
 835         vd_first = list_first_entry(&chan->vc.desc_submitted,
 836                                     struct virt_dma_desc, node);
 837         dev_dbg(&chan->vc.chan.dev->device,
 838                 "%s(): txd %p[%x]", __func__, vd_first, vd_first->tx.cookie);
 839
 840         vchan_issue_pending(&chan->vc);
 841         if (!pxad_try_hotchain(&chan->vc, vd_first))
 842                 pxad_launch_chan(chan, to_pxad_sw_desc(vd_first));
 843 out:
 844         spin_unlock_irqrestore(&chan->vc.lock, flags);
 845 }
 846
 847 static inline struct dma_async_tx_descriptor *
 848 pxad_tx_prep(struct virt_dma_chan *vc, struct virt_dma_desc *vd,
 849                  unsigned long tx_flags)
 850 {
 851         struct dma_async_tx_descriptor *tx;
 852         struct pxad_chan *chan = container_of(vc, struct pxad_chan, vc);
 853
 854         INIT_LIST_HEAD(&vd->node);
 855         tx = vchan_tx_prep(vc, vd, tx_flags);
 856         tx->tx_submit = pxad_tx_submit;
 857         dev_dbg(&chan->vc.chan.dev->device,
 858                 "%s(): vc=%p txd=%p[%x] flags=0x%lx\n", __func__,
 859                 vc, vd, vd->tx.cookie,
 860                 tx_flags);
 861
 862         return tx;
 863 }
 864
 865 static void pxad_get_config(struct pxad_chan *chan,
 866                             enum dma_transfer_direction dir,
 867                             u32 *dcmd, u32 *dev_src, u32 *dev_dst)
 868 {
 869         u32 maxburst = 0, dev_addr = 0;
 870         enum dma_slave_buswidth width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
 871         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
 872
 873         *dcmd = 0;
 874         if (dir == DMA_DEV_TO_MEM) {
 875                 maxburst = chan->cfg.src_maxburst;
 876                 width = chan->cfg.src_addr_width;
 877                 dev_addr = chan->cfg.src_addr;
 878                 *dev_src = dev_addr;
 879                 *dcmd |= PXA_DCMD_INCTRGADDR;
 880                 if (chan->drcmr <= pdev->nr_requestors)
 881                         *dcmd |= PXA_DCMD_FLOWSRC;
 882         }
 883         if (dir == DMA_MEM_TO_DEV) {
 884                 maxburst = chan->cfg.dst_maxburst;
 885                 width = chan->cfg.dst_addr_width;
 886                 dev_addr = chan->cfg.dst_addr;
 887                 *dev_dst = dev_addr;
 888                 *dcmd |= PXA_DCMD_INCSRCADDR;
 889                 if (chan->drcmr <= pdev->nr_requestors)
 890                         *dcmd |= PXA_DCMD_FLOWTRG;
 891         }
 892         if (dir == DMA_MEM_TO_MEM)
 893                 *dcmd |= PXA_DCMD_BURST32 | PXA_DCMD_INCTRGADDR |
 894                         PXA_DCMD_INCSRCADDR;
 895
 896         dev_dbg(&chan->vc.chan.dev->device,
 897                 "%s(): dev_addr=0x%x maxburst=%d width=%d  dir=%d\n",
 898                 __func__, dev_addr, maxburst, width, dir);
 899
 900         if (width == DMA_SLAVE_BUSWIDTH_1_BYTE)
 901                 *dcmd |= PXA_DCMD_WIDTH1;
 902         else if (width == DMA_SLAVE_BUSWIDTH_2_BYTES)
 903                 *dcmd |= PXA_DCMD_WIDTH2;
 904         else if (width == DMA_SLAVE_BUSWIDTH_4_BYTES)
 905                 *dcmd |= PXA_DCMD_WIDTH4;
 906
 907         if (maxburst == 8)
 908                 *dcmd |= PXA_DCMD_BURST8;
 909         else if (maxburst == 16)
 910                 *dcmd |= PXA_DCMD_BURST16;
 911         else if (maxburst == 32)
 912                 *dcmd |= PXA_DCMD_BURST32;
 913
 914         /* FIXME: drivers should be ported over to use the filter
 915          * function. Once that's done, the following two lines can
 916          * be removed.
 917          */
 918         if (chan->cfg.slave_id)
 919                 chan->drcmr = chan->cfg.slave_id;
 920 }
 921
 922 static struct dma_async_tx_descriptor *
 923 pxad_prep_memcpy(struct dma_chan *dchan,
 924                  dma_addr_t dma_dst, dma_addr_t dma_src,
 925                  size_t len, unsigned long flags)
 926 {
 927         struct pxad_chan *chan = to_pxad_chan(dchan);
 928         struct pxad_desc_sw *sw_desc;
 929         struct pxad_desc_hw *hw_desc;
 930         u32 dcmd;
 931         unsigned int i, nb_desc = 0;
 932         size_t copy;
 933
 934         if (!dchan || !len)
 935                 return NULL;
 936
 937         dev_dbg(&chan->vc.chan.dev->device,
 938                 "%s(): dma_dst=0x%lx dma_src=0x%lx len=%zu flags=%lx\n",
 939                 __func__, (unsigned long)dma_dst, (unsigned long)dma_src,
 940                 len, flags);
 941         pxad_get_config(chan, DMA_MEM_TO_MEM, &dcmd, NULL, NULL);
 942
 943         nb_desc = DIV_ROUND_UP(len, PDMA_MAX_DESC_BYTES);
 944         sw_desc = pxad_alloc_desc(chan, nb_desc + 1);
 945         if (!sw_desc)
 946                 return NULL;
 947         sw_desc->len = len;
 948
 949         if (!IS_ALIGNED(dma_src, 1 << PDMA_ALIGNMENT) ||
 950             !IS_ALIGNED(dma_dst, 1 << PDMA_ALIGNMENT))
 951                 sw_desc->misaligned = true;
 952
 953         i = 0;
 954         do {
 955                 hw_desc = sw_desc->hw_desc[i++];
 956                 copy = min_t(size_t, len, PDMA_MAX_DESC_BYTES);
 957                 hw_desc->dcmd = dcmd | (PXA_DCMD_LENGTH & copy);
 958                 hw_desc->dsadr = dma_src;
 959                 hw_desc->dtadr = dma_dst;
 960                 len -= copy;
 961                 dma_src += copy;
 962                 dma_dst += copy;
 963         } while (len);
 964         set_updater_desc(sw_desc, flags);
 965
 966         return pxad_tx_prep(&chan->vc, &sw_desc->vd, flags);
 967 }
 968
 969 static struct dma_async_tx_descriptor *
 970 pxad_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
 971                    unsigned int sg_len, enum dma_transfer_direction dir,
 972                    unsigned long flags, void *context)
 973 {
 974         struct pxad_chan *chan = to_pxad_chan(dchan);
 975         struct pxad_desc_sw *sw_desc;
 976         size_t len, avail;
 977         struct scatterlist *sg;
 978         dma_addr_t dma;
 979         u32 dcmd, dsadr = 0, dtadr = 0;
 980         unsigned int nb_desc = 0, i, j = 0;
 981
 982         if ((sgl == NULL) || (sg_len == 0))
 983                 return NULL;
 984
 985         pxad_get_config(chan, dir, &dcmd, &dsadr, &dtadr);
 986         dev_dbg(&chan->vc.chan.dev->device,
 987                 "%s(): dir=%d flags=%lx\n", __func__, dir, flags);
 988
 989         for_each_sg(sgl, sg, sg_len, i)
 990                 nb_desc += DIV_ROUND_UP(sg_dma_len(sg), PDMA_MAX_DESC_BYTES);
 991         sw_desc = pxad_alloc_desc(chan, nb_desc + 1);
 992         if (!sw_desc)
 993                 return NULL;
 994
 995         for_each_sg(sgl, sg, sg_len, i) {
 996                 dma = sg_dma_address(sg);
 997                 avail = sg_dma_len(sg);
 998                 sw_desc->len += avail;
 999
1000                 do {
1001                         len = min_t(size_t, avail, PDMA_MAX_DESC_BYTES);
1002                         if (dma & 0x7)
1003                                 sw_desc->misaligned = true;
1004
1005                         sw_desc->hw_desc[j]->dcmd =
1006                                 dcmd | (PXA_DCMD_LENGTH & len);
1007                         sw_desc->hw_desc[j]->dsadr = dsadr ? dsadr : dma;
1008                         sw_desc->hw_desc[j++]->dtadr = dtadr ? dtadr : dma;
1009
1010                         dma += len;
1011                         avail -= len;
1012                 } while (avail);
1013         }
1014         set_updater_desc(sw_desc, flags);
1015
1016         return pxad_tx_prep(&chan->vc, &sw_desc->vd, flags);
1017 }
1018
1019 static struct dma_async_tx_descriptor *
1020 pxad_prep_dma_cyclic(struct dma_chan *dchan,
1021                      dma_addr_t buf_addr, size_t len, size_t period_len,
1022                      enum dma_transfer_direction dir, unsigned long flags)
1023 {
1024         struct pxad_chan *chan = to_pxad_chan(dchan);
1025         struct pxad_desc_sw *sw_desc;
1026         struct pxad_desc_hw **phw_desc;
1027         dma_addr_t dma;
1028         u32 dcmd, dsadr = 0, dtadr = 0;
1029         unsigned int nb_desc = 0;
1030
1031         if (!dchan || !len || !period_len)
1032                 return NULL;
1033         if ((dir != DMA_DEV_TO_MEM) && (dir != DMA_MEM_TO_DEV)) {
1034                 dev_err(&chan->vc.chan.dev->device,
1035                         "Unsupported direction for cyclic DMA\n");
1036                 return NULL;
1037         }
1038         /* the buffer length must be a multiple of period_len */
1039         if (len % period_len != 0 || period_len > PDMA_MAX_DESC_BYTES ||
1040             !IS_ALIGNED(period_len, 1 << PDMA_ALIGNMENT))
1041                 return NULL;
1042
1043         pxad_get_config(chan, dir, &dcmd, &dsadr, &dtadr);
1044         dcmd |= PXA_DCMD_ENDIRQEN | (PXA_DCMD_LENGTH & period_len);
1045         dev_dbg(&chan->vc.chan.dev->device,
1046                 "%s(): buf_addr=0x%lx len=%zu period=%zu dir=%d flags=%lx\n",
1047                 __func__, (unsigned long)buf_addr, len, period_len, dir, flags);
1048
1049         nb_desc = DIV_ROUND_UP(period_len, PDMA_MAX_DESC_BYTES);
1050         nb_desc *= DIV_ROUND_UP(len, period_len);
1051         sw_desc = pxad_alloc_desc(chan, nb_desc + 1);
1052         if (!sw_desc)
1053                 return NULL;
1054         sw_desc->cyclic = true;
1055         sw_desc->len = len;
1056
1057         phw_desc = sw_desc->hw_desc;
1058         dma = buf_addr;
1059         do {
1060                 phw_desc[0]->dsadr = dsadr ? dsadr : dma;
1061                 phw_desc[0]->dtadr = dtadr ? dtadr : dma;
1062                 phw_desc[0]->dcmd = dcmd;
1063                 phw_desc++;
1064                 dma += period_len;
1065                 len -= period_len;
1066         } while (len);
1067         set_updater_desc(sw_desc, flags);
1068
1069         return pxad_tx_prep(&chan->vc, &sw_desc->vd, flags);
1070 }
1071
1072 static int pxad_config(struct dma_chan *dchan,
1073                        struct dma_slave_config *cfg)
1074 {
1075         struct pxad_chan *chan = to_pxad_chan(dchan);
1076
1077         if (!dchan)
1078                 return -EINVAL;
1079
1080         chan->cfg = *cfg;
1081         return 0;
1082 }
1083
1084 static int pxad_terminate_all(struct dma_chan *dchan)
1085 {
1086         struct pxad_chan *chan = to_pxad_chan(dchan);
1087         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
1088         struct virt_dma_desc *vd = NULL;
1089         unsigned long flags;
1090         struct pxad_phy *phy;
1091         LIST_HEAD(head);
1092
1093         dev_dbg(&chan->vc.chan.dev->device,
1094                 "%s(): vchan %p: terminate all\n", __func__, &chan->vc);
1095
1096         spin_lock_irqsave(&chan->vc.lock, flags);
1097         vchan_get_all_descriptors(&chan->vc, &head);
1098
1099         list_for_each_entry(vd, &head, node) {
1100                 dev_dbg(&chan->vc.chan.dev->device,
1101                         "%s(): cancelling txd %p[%x] (completed=%d)", __func__,
1102                         vd, vd->tx.cookie, is_desc_completed(vd));
1103         }
1104
1105         phy = chan->phy;
1106         if (phy) {
1107                 phy_disable(chan->phy);
1108                 pxad_free_phy(chan);
1109                 chan->phy = NULL;
1110                 spin_lock(&pdev->phy_lock);
1111                 phy->vchan = NULL;
1112                 spin_unlock(&pdev->phy_lock);
1113         }
1114         spin_unlock_irqrestore(&chan->vc.lock, flags);
1115         vchan_dma_desc_free_list(&chan->vc, &head);
1116
1117         return 0;
1118 }
1119
1120 static unsigned int pxad_residue(struct pxad_chan *chan,
1121                                  dma_cookie_t cookie)
1122 {
1123         struct virt_dma_desc *vd = NULL;
1124         struct pxad_desc_sw *sw_desc = NULL;
1125         struct pxad_desc_hw *hw_desc = NULL;
1126         u32 curr, start, len, end, residue = 0;
1127         unsigned long flags;
1128         bool passed = false;
1129         int i;
1130
1131         /*
1132          * If the channel does not have a phy pointer anymore, it has already
1133          * been completed. Therefore, its residue is 0.
1134          */
1135         if (!chan->phy)
1136                 return 0;
1137
1138         spin_lock_irqsave(&chan->vc.lock, flags);
1139
1140         vd = vchan_find_desc(&chan->vc, cookie);
1141         if (!vd)
1142                 goto out;
1143
1144         sw_desc = to_pxad_sw_desc(vd);
1145         if (sw_desc->hw_desc[0]->dcmd & PXA_DCMD_INCSRCADDR)
1146                 curr = phy_readl_relaxed(chan->phy, DSADR);
1147         else
1148                 curr = phy_readl_relaxed(chan->phy, DTADR);
1149
1150         /*
1151          * curr has to be actually read before checking descriptor
1152          * completion, so that a curr inside a status updater
1153          * descriptor implies the following test returns true, and
1154          * preventing reordering of curr load and the test.
1155          */
1156         rmb();
1157         if (is_desc_completed(vd))
1158                 goto out;
1159
1160         for (i = 0; i < sw_desc->nb_desc - 1; i++) {
1161                 hw_desc = sw_desc->hw_desc[i];
1162                 if (sw_desc->hw_desc[0]->dcmd & PXA_DCMD_INCSRCADDR)
1163                         start = hw_desc->dsadr;
1164                 else
1165                         start = hw_desc->dtadr;
1166                 len = hw_desc->dcmd & PXA_DCMD_LENGTH;
1167                 end = start + len;
1168
1169                 /*
1170                  * 'passed' will be latched once we found the descriptor
1171                  * which lies inside the boundaries of the curr
1172                  * pointer. All descriptors that occur in the list
1173                  * _after_ we found that partially handled descriptor
1174                  * are still to be processed and are hence added to the
1175                  * residual bytes counter.
1176                  */
1177
1178                 if (passed) {
1179                         residue += len;
1180                 } else if (curr >= start && curr <= end) {
1181                         residue += end - curr;
1182                         passed = true;
1183                 }
1184         }
1185         if (!passed)
1186                 residue = sw_desc->len;
1187
1188 out:
1189         spin_unlock_irqrestore(&chan->vc.lock, flags);
1190         dev_dbg(&chan->vc.chan.dev->device,
1191                 "%s(): txd %p[%x] sw_desc=%p: %d\n",
1192                 __func__, vd, cookie, sw_desc, residue);
1193         return residue;
1194 }
1195
1196 static enum dma_status pxad_tx_status(struct dma_chan *dchan,
1197                                       dma_cookie_t cookie,
1198                                       struct dma_tx_state *txstate)
1199 {
1200         struct pxad_chan *chan = to_pxad_chan(dchan);
1201         enum dma_status ret;
1202
1203         if (cookie == chan->bus_error)
1204                 return DMA_ERROR;
1205
1206         ret = dma_cookie_status(dchan, cookie, txstate);
1207         if (likely(txstate && (ret != DMA_ERROR)))
1208                 dma_set_residue(txstate, pxad_residue(chan, cookie));
1209
1210         return ret;
1211 }
1212
1213 static void pxad_synchronize(struct dma_chan *dchan)
1214 {
1215         struct pxad_chan *chan = to_pxad_chan(dchan);
1216
1217         wait_event(chan->wq_state, !is_chan_running(chan));
1218         vchan_synchronize(&chan->vc);
1219 }
1220
1221 static void pxad_free_channels(struct dma_device *dmadev)
1222 {
1223         struct pxad_chan *c, *cn;
1224
1225         list_for_each_entry_safe(c, cn, &dmadev->channels,
1226                                  vc.chan.device_node) {
1227                 list_del(&c->vc.chan.device_node);
1228                 tasklet_kill(&c->vc.task);
1229         }
1230 }
1231
1232 static int pxad_remove(struct platform_device *op)
1233 {
1234         struct pxad_device *pdev = platform_get_drvdata(op);
1235
1236         pxad_cleanup_debugfs(pdev);
1237         pxad_free_channels(&pdev->slave);
1238         return 0;
1239 }
1240
1241 static int pxad_init_phys(struct platform_device *op,
1242                           struct pxad_device *pdev,
1243                           unsigned int nb_phy_chans)
1244 {
1245         int irq0, irq, nr_irq = 0, i, ret;
1246         struct pxad_phy *phy;
1247
1248         irq0 = platform_get_irq(op, 0);
1249         if (irq0 < 0)
1250                 return irq0;
1251
1252         pdev->phys = devm_kcalloc(&op->dev, nb_phy_chans,
1253                                   sizeof(pdev->phys[0]), GFP_KERNEL);
1254         if (!pdev->phys)
1255                 return -ENOMEM;
1256
1257         for (i = 0; i < nb_phy_chans; i++)
1258                 if (platform_get_irq(op, i) > 0)
1259                         nr_irq++;
1260
1261         for (i = 0; i < nb_phy_chans; i++) {
1262                 phy = &pdev->phys[i];
1263                 phy->base = pdev->base;
1264                 phy->idx = i;
1265                 irq = platform_get_irq(op, i);
1266                 if ((nr_irq > 1) && (irq > 0))
1267                         ret = devm_request_irq(&op->dev, irq,
1268                                                pxad_chan_handler,
1269                                                IRQF_SHARED, "pxa-dma", phy);
1270                 if ((nr_irq == 1) && (i == 0))
1271                         ret = devm_request_irq(&op->dev, irq0,
1272                                                pxad_int_handler,
1273                                                IRQF_SHARED, "pxa-dma", pdev);
1274                 if (ret) {
1275                         dev_err(pdev->slave.dev,
1276                                 "%s(): can't request irq %d:%d\n", __func__,
1277                                 irq, ret);
1278                         return ret;
1279                 }
1280         }
1281
1282         return 0;
1283 }
1284
1285 static const struct of_device_id pxad_dt_ids[] = {
1286         { .compatible = "marvell,pdma-1.0", },
1287         {}
1288 };
1289 MODULE_DEVICE_TABLE(of, pxad_dt_ids);
1290
1291 static struct dma_chan *pxad_dma_xlate(struct of_phandle_args *dma_spec,
1292                                            struct of_dma *ofdma)
1293 {
1294         struct pxad_device *d = ofdma->of_dma_data;
1295         struct dma_chan *chan;
1296
1297         chan = dma_get_any_slave_channel(&d->slave);
1298         if (!chan)
1299                 return NULL;
1300
1301         to_pxad_chan(chan)->drcmr = dma_spec->args[0];
1302         to_pxad_chan(chan)->prio = dma_spec->args[1];
1303
1304         return chan;
1305 }
1306
1307 static int pxad_init_dmadev(struct platform_device *op,
1308                             struct pxad_device *pdev,
1309                             unsigned int nr_phy_chans,
1310                             unsigned int nr_requestors)
1311 {
1312         int ret;
1313         unsigned int i;
1314         struct pxad_chan *c;
1315
1316         pdev->nr_chans = nr_phy_chans;
1317         pdev->nr_requestors = nr_requestors;
1318         INIT_LIST_HEAD(&pdev->slave.channels);
1319         pdev->slave.device_alloc_chan_resources = pxad_alloc_chan_resources;
1320         pdev->slave.device_free_chan_resources = pxad_free_chan_resources;
1321         pdev->slave.device_tx_status = pxad_tx_status;
1322         pdev->slave.device_issue_pending = pxad_issue_pending;
1323         pdev->slave.device_config = pxad_config;
1324         pdev->slave.device_synchronize = pxad_synchronize;
1325         pdev->slave.device_terminate_all = pxad_terminate_all;
1326
1327         if (op->dev.coherent_dma_mask)
1328                 dma_set_mask(&op->dev, op->dev.coherent_dma_mask);
1329         else
1330                 dma_set_mask(&op->dev, DMA_BIT_MASK(32));
1331
1332         ret = pxad_init_phys(op, pdev, nr_phy_chans);
1333         if (ret)
1334                 return ret;
1335
1336         for (i = 0; i < nr_phy_chans; i++) {
1337                 c = devm_kzalloc(&op->dev, sizeof(*c), GFP_KERNEL);
1338                 if (!c)
1339                         return -ENOMEM;
1340
1341                 c->drcmr = U32_MAX;
1342                 c->prio = PXAD_PRIO_LOWEST;
1343                 c->vc.desc_free = pxad_free_desc;
1344                 vchan_init(&c->vc, &pdev->slave);
1345                 init_waitqueue_head(&c->wq_state);
1346         }
1347
1348         return dmaenginem_async_device_register(&pdev->slave);
1349 }
1350
1351 static int pxad_probe(struct platform_device *op)
1352 {
1353         struct pxad_device *pdev;
1354         const struct of_device_id *of_id;
1355         const struct dma_slave_map *slave_map = NULL;
1356         struct mmp_dma_platdata *pdata = dev_get_platdata(&op->dev);
1357         struct resource *iores;
1358         int ret, dma_channels = 0, nb_requestors = 0, slave_map_cnt = 0;
1359         const enum dma_slave_buswidth widths =
1360                 DMA_SLAVE_BUSWIDTH_1_BYTE   | DMA_SLAVE_BUSWIDTH_2_BYTES |
1361                 DMA_SLAVE_BUSWIDTH_4_BYTES;
1362
1363         pdev = devm_kzalloc(&op->dev, sizeof(*pdev), GFP_KERNEL);
1364         if (!pdev)
1365                 return -ENOMEM;
1366
1367         spin_lock_init(&pdev->phy_lock);
1368
1369         iores = platform_get_resource(op, IORESOURCE_MEM, 0);
1370         pdev->base = devm_ioremap_resource(&op->dev, iores);
1371         if (IS_ERR(pdev->base))
1372                 return PTR_ERR(pdev->base);
1373
1374         of_id = of_match_device(pxad_dt_ids, &op->dev);
1375         if (of_id) {
1376                 of_property_read_u32(op->dev.of_node, "#dma-channels",
1377                                      &dma_channels);
1378                 ret = of_property_read_u32(op->dev.of_node, "#dma-requests",
1379                                            &nb_requestors);
1380                 if (ret) {
1381                         dev_warn(pdev->slave.dev,
1382                                  "#dma-requests set to default 32 as missing in OF: %d",
1383                                  ret);
1384                         nb_requestors = 32;
1385                 }
1386         } else if (pdata && pdata->dma_channels) {
1387                 dma_channels = pdata->dma_channels;
1388                 nb_requestors = pdata->nb_requestors;
1389                 slave_map = pdata->slave_map;
1390                 slave_map_cnt = pdata->slave_map_cnt;
1391         } else {
1392                 dma_channels = 32;      /* default 32 channel */
1393         }
1394
1395         dma_cap_set(DMA_SLAVE, pdev->slave.cap_mask);
1396         dma_cap_set(DMA_MEMCPY, pdev->slave.cap_mask);
1397         dma_cap_set(DMA_CYCLIC, pdev->slave.cap_mask);
1398         dma_cap_set(DMA_PRIVATE, pdev->slave.cap_mask);
1399         pdev->slave.device_prep_dma_memcpy = pxad_prep_memcpy;
1400         pdev->slave.device_prep_slave_sg = pxad_prep_slave_sg;
1401         pdev->slave.device_prep_dma_cyclic = pxad_prep_dma_cyclic;
1402         pdev->slave.filter.map = slave_map;
1403         pdev->slave.filter.mapcnt = slave_map_cnt;
1404         pdev->slave.filter.fn = pxad_filter_fn;
1405
1406         pdev->slave.copy_align = PDMA_ALIGNMENT;
1407         pdev->slave.src_addr_widths = widths;
1408         pdev->slave.dst_addr_widths = widths;
1409         pdev->slave.directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
1410         pdev->slave.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
1411         pdev->slave.descriptor_reuse = true;
1412
1413         pdev->slave.dev = &op->dev;
1414         ret = pxad_init_dmadev(op, pdev, dma_channels, nb_requestors);
1415         if (ret) {
1416                 dev_err(pdev->slave.dev, "unable to register\n");
1417                 return ret;
1418         }
1419
1420         if (op->dev.of_node) {
1421                 /* Device-tree DMA controller registration */
1422                 ret = of_dma_controller_register(op->dev.of_node,
1423                                                  pxad_dma_xlate, pdev);
1424                 if (ret < 0) {
1425                         dev_err(pdev->slave.dev,
1426                                 "of_dma_controller_register failed\n");
1427                         return ret;
1428                 }
1429         }
1430
1431         platform_set_drvdata(op, pdev);
1432         pxad_init_debugfs(pdev);
1433         dev_info(pdev->slave.dev, "initialized %d channels on %d requestors\n",
1434                  dma_channels, nb_requestors);
1435         return 0;
1436 }
1437
1438 static const struct platform_device_id pxad_id_table[] = {
1439         { "pxa-dma", },
1440         { },
1441 };
1442
1443 static struct platform_driver pxad_driver = {
1444         .driver         = {
1445                 .name   = "pxa-dma",
1446                 .of_match_table = pxad_dt_ids,
1447         },
1448         .id_table       = pxad_id_table,
1449         .probe          = pxad_probe,
1450         .remove         = pxad_remove,
1451 };
1452
1453 static bool pxad_filter_fn(struct dma_chan *chan, void *param)
1454 {
1455         struct pxad_chan *c = to_pxad_chan(chan);
1456         struct pxad_param *p = param;
1457
1458         if (chan->device->dev->driver != &pxad_driver.driver)
1459                 return false;
1460
1461         c->drcmr = p->drcmr;
1462         c->prio = p->prio;
1463
1464         return true;
1465 }
1466
1467 module_platform_driver(pxad_driver);
1468
1469 MODULE_DESCRIPTION("Marvell PXA Peripheral DMA Driver");
1470 MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
1471 MODULE_LICENSE("GPL v2");