drivers/dma/pxa_dma.c

   1 /*
   2  * Copyright 2015 Robert Jarzmik <robert.jarzmik@free.fr>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  */
   8
   9 #include <linux/err.h>
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/types.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/dma-mapping.h>
  15 #include <linux/slab.h>
  16 #include <linux/dmaengine.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/device.h>
  19 #include <linux/platform_data/mmp_dma.h>
  20 #include <linux/dmapool.h>
  21 #include <linux/of_device.h>
  22 #include <linux/of_dma.h>
  23 #include <linux/of.h>
  24 #include <linux/wait.h>
  25 #include <linux/dma/pxa-dma.h>
  26
  27 #include "dmaengine.h"
  28 #include "virt-dma.h"
  29
  30 #define DCSR(n)         (0x0000 + ((n) << 2))
  31 #define DALGN(n)        0x00a0
  32 #define DINT            0x00f0
  33 #define DDADR(n)        (0x0200 + ((n) << 4))
  34 #define DSADR(n)        (0x0204 + ((n) << 4))
  35 #define DTADR(n)        (0x0208 + ((n) << 4))
  36 #define DCMD(n)         (0x020c + ((n) << 4))
  37
  38 #define PXA_DCSR_RUN            BIT(31) /* Run Bit (read / write) */
  39 #define PXA_DCSR_NODESC         BIT(30) /* No-Descriptor Fetch (read / write) */
  40 #define PXA_DCSR_STOPIRQEN      BIT(29) /* Stop Interrupt Enable (R/W) */
  41 #define PXA_DCSR_REQPEND        BIT(8)  /* Request Pending (read-only) */
  42 #define PXA_DCSR_STOPSTATE      BIT(3)  /* Stop State (read-only) */
  43 #define PXA_DCSR_ENDINTR        BIT(2)  /* End Interrupt (read / write) */
  44 #define PXA_DCSR_STARTINTR      BIT(1)  /* Start Interrupt (read / write) */
  45 #define PXA_DCSR_BUSERR         BIT(0)  /* Bus Error Interrupt (read / write) */
  46
  47 #define PXA_DCSR_EORIRQEN       BIT(28) /* End of Receive IRQ Enable (R/W) */
  48 #define PXA_DCSR_EORJMPEN       BIT(27) /* Jump to next descriptor on EOR */
  49 #define PXA_DCSR_EORSTOPEN      BIT(26) /* STOP on an EOR */
  50 #define PXA_DCSR_SETCMPST       BIT(25) /* Set Descriptor Compare Status */
  51 #define PXA_DCSR_CLRCMPST       BIT(24) /* Clear Descriptor Compare Status */
  52 #define PXA_DCSR_CMPST          BIT(10) /* The Descriptor Compare Status */
  53 #define PXA_DCSR_EORINTR        BIT(9)  /* The end of Receive */
  54
  55 #define DRCMR_MAPVLD    BIT(7)  /* Map Valid (read / write) */
  56 #define DRCMR_CHLNUM    0x1f    /* mask for Channel Number (read / write) */
  57
  58 #define DDADR_DESCADDR  0xfffffff0      /* Address of next descriptor (mask) */
  59 #define DDADR_STOP      BIT(0)  /* Stop (read / write) */
  60
  61 #define PXA_DCMD_INCSRCADDR     BIT(31) /* Source Address Increment Setting. */
  62 #define PXA_DCMD_INCTRGADDR     BIT(30) /* Target Address Increment Setting. */
  63 #define PXA_DCMD_FLOWSRC        BIT(29) /* Flow Control by the source. */
  64 #define PXA_DCMD_FLOWTRG        BIT(28) /* Flow Control by the target. */
  65 #define PXA_DCMD_STARTIRQEN     BIT(22) /* Start Interrupt Enable */
  66 #define PXA_DCMD_ENDIRQEN       BIT(21) /* End Interrupt Enable */
  67 #define PXA_DCMD_ENDIAN         BIT(18) /* Device Endian-ness. */
  68 #define PXA_DCMD_BURST8         (1 << 16)       /* 8 byte burst */
  69 #define PXA_DCMD_BURST16        (2 << 16)       /* 16 byte burst */
  70 #define PXA_DCMD_BURST32        (3 << 16)       /* 32 byte burst */
  71 #define PXA_DCMD_WIDTH1         (1 << 14)       /* 1 byte width */
  72 #define PXA_DCMD_WIDTH2         (2 << 14)       /* 2 byte width (HalfWord) */
  73 #define PXA_DCMD_WIDTH4         (3 << 14)       /* 4 byte width (Word) */
  74 #define PXA_DCMD_LENGTH         0x01fff         /* length mask (max = 8K - 1) */
  75
  76 #define PDMA_ALIGNMENT          3
  77 #define PDMA_MAX_DESC_BYTES     (PXA_DCMD_LENGTH & ~((1 << PDMA_ALIGNMENT) - 1))
  78
  79 struct pxad_desc_hw {
  80         u32 ddadr;      /* Points to the next descriptor + flags */
  81         u32 dsadr;      /* DSADR value for the current transfer */
  82         u32 dtadr;      /* DTADR value for the current transfer */
  83         u32 dcmd;       /* DCMD value for the current transfer */
  84 } __aligned(16);
  85
  86 struct pxad_desc_sw {
  87         struct virt_dma_desc    vd;             /* Virtual descriptor */
  88         int                     nb_desc;        /* Number of hw. descriptors */
  89         size_t                  len;            /* Number of bytes xfered */
  90         dma_addr_t              first;          /* First descriptor's addr */
  91
  92         /* At least one descriptor has an src/dst address not multiple of 8 */
  93         bool                    misaligned;
  94         bool                    cyclic;
  95         struct dma_pool         *desc_pool;     /* Channel's used allocator */
  96
  97         struct pxad_desc_hw     *hw_desc[];     /* DMA coherent descriptors */
  98 };
  99
 100 struct pxad_phy {
 101         int                     idx;
 102         void __iomem            *base;
 103         struct pxad_chan        *vchan;
 104 };
 105
 106 struct pxad_chan {
 107         struct virt_dma_chan    vc;             /* Virtual channel */
 108         u32                     drcmr;          /* Requestor of the channel */
 109         enum pxad_chan_prio     prio;           /* Required priority of phy */
 110         /*
 111          * At least one desc_sw in submitted or issued transfers on this channel
 112          * has one address such as: addr % 8 != 0. This implies the DALGN
 113          * setting on the phy.
 114          */
 115         bool                    misaligned;
 116         struct dma_slave_config cfg;            /* Runtime config */
 117
 118         /* protected by vc->lock */
 119         struct pxad_phy         *phy;
 120         struct dma_pool         *desc_pool;     /* Descriptors pool */
 121         dma_cookie_t            bus_error;
 122
 123         wait_queue_head_t       wq_state;
 124 };
 125
 126 struct pxad_device {
 127         struct dma_device               slave;
 128         int                             nr_chans;
 129         int                             nr_requestors;
 130         void __iomem                    *base;
 131         struct pxad_phy                 *phys;
 132         spinlock_t                      phy_lock;       /* Phy association */
 133 #ifdef CONFIG_DEBUG_FS
 134         struct dentry                   *dbgfs_root;
 135         struct dentry                   *dbgfs_state;
 136         struct dentry                   **dbgfs_chan;
 137 #endif
 138 };
 139
 140 #define tx_to_pxad_desc(tx)                                     \
 141         container_of(tx, struct pxad_desc_sw, async_tx)
 142 #define to_pxad_chan(dchan)                                     \
 143         container_of(dchan, struct pxad_chan, vc.chan)
 144 #define to_pxad_dev(dmadev)                                     \
 145         container_of(dmadev, struct pxad_device, slave)
 146 #define to_pxad_sw_desc(_vd)                            \
 147         container_of((_vd), struct pxad_desc_sw, vd)
 148
 149 #define _phy_readl_relaxed(phy, _reg)                                   \
 150         readl_relaxed((phy)->base + _reg((phy)->idx))
 151 #define phy_readl_relaxed(phy, _reg)                                    \
 152         ({                                                              \
 153                 u32 _v;                                                 \
 154                 _v = readl_relaxed((phy)->base + _reg((phy)->idx));     \
 155                 dev_vdbg(&phy->vchan->vc.chan.dev->device,              \
 156                          "%s(): readl(%s): 0x%08x\n", __func__, #_reg,  \
 157                           _v);                                          \
 158                 _v;                                                     \
 159         })
 160 #define phy_writel(phy, val, _reg)                                      \
 161         do {                                                            \
 162                 writel((val), (phy)->base + _reg((phy)->idx));          \
 163                 dev_vdbg(&phy->vchan->vc.chan.dev->device,              \
 164                          "%s(): writel(0x%08x, %s)\n",                  \
 165                          __func__, (u32)(val), #_reg);                  \
 166         } while (0)
 167 #define phy_writel_relaxed(phy, val, _reg)                              \
 168         do {                                                            \
 169                 writel_relaxed((val), (phy)->base + _reg((phy)->idx));  \
 170                 dev_vdbg(&phy->vchan->vc.chan.dev->device,              \
 171                          "%s(): writel_relaxed(0x%08x, %s)\n",          \
 172                          __func__, (u32)(val), #_reg);                  \
 173         } while (0)
 174
 175 static unsigned int pxad_drcmr(unsigned int line)
 176 {
 177         if (line < 64)
 178                 return 0x100 + line * 4;
 179         return 0x1000 + line * 4;
 180 }
 181
 182 /*
 183  * Debug fs
 184  */
 185 #ifdef CONFIG_DEBUG_FS
 186 #include <linux/debugfs.h>
 187 #include <linux/uaccess.h>
 188 #include <linux/seq_file.h>
 189
 190 static int dbg_show_requester_chan(struct seq_file *s, void *p)
 191 {
 192         struct pxad_phy *phy = s->private;
 193         int i;
 194         u32 drcmr;
 195
 196         seq_printf(s, "DMA channel %d requester :\n", phy->idx);
 197         for (i = 0; i < 70; i++) {
 198                 drcmr = readl_relaxed(phy->base + pxad_drcmr(i));
 199                 if ((drcmr & DRCMR_CHLNUM) == phy->idx)
 200                         seq_printf(s, "\tRequester %d (MAPVLD=%d)\n", i,
 201                                    !!(drcmr & DRCMR_MAPVLD));
 202         }
 203         return 0;
 204 }
 205
 206 static inline int dbg_burst_from_dcmd(u32 dcmd)
 207 {
 208         int burst = (dcmd >> 16) & 0x3;
 209
 210         return burst ? 4 << burst : 0;
 211 }
 212
 213 static int is_phys_valid(unsigned long addr)
 214 {
 215         return pfn_valid(__phys_to_pfn(addr));
 216 }
 217
 218 #define PXA_DCSR_STR(flag) (dcsr & PXA_DCSR_##flag ? #flag" " : "")
 219 #define PXA_DCMD_STR(flag) (dcmd & PXA_DCMD_##flag ? #flag" " : "")
 220
 221 static int dbg_show_descriptors(struct seq_file *s, void *p)
 222 {
 223         struct pxad_phy *phy = s->private;
 224         int i, max_show = 20, burst, width;
 225         u32 dcmd;
 226         unsigned long phys_desc, ddadr;
 227         struct pxad_desc_hw *desc;
 228
 229         phys_desc = ddadr = _phy_readl_relaxed(phy, DDADR);
 230
 231         seq_printf(s, "DMA channel %d descriptors :\n", phy->idx);
 232         seq_printf(s, "[%03d] First descriptor unknown\n", 0);
 233         for (i = 1; i < max_show && is_phys_valid(phys_desc); i++) {
 234                 desc = phys_to_virt(phys_desc);
 235                 dcmd = desc->dcmd;
 236                 burst = dbg_burst_from_dcmd(dcmd);
 237                 width = (1 << ((dcmd >> 14) & 0x3)) >> 1;
 238
 239                 seq_printf(s, "[%03d] Desc at %08lx(virt %p)\n",
 240                            i, phys_desc, desc);
 241                 seq_printf(s, "\tDDADR = %08x\n", desc->ddadr);
 242                 seq_printf(s, "\tDSADR = %08x\n", desc->dsadr);
 243                 seq_printf(s, "\tDTADR = %08x\n", desc->dtadr);
 244                 seq_printf(s, "\tDCMD  = %08x (%s%s%s%s%s%s%sburst=%d width=%d len=%d)\n",
 245                            dcmd,
 246                            PXA_DCMD_STR(INCSRCADDR), PXA_DCMD_STR(INCTRGADDR),
 247                            PXA_DCMD_STR(FLOWSRC), PXA_DCMD_STR(FLOWTRG),
 248                            PXA_DCMD_STR(STARTIRQEN), PXA_DCMD_STR(ENDIRQEN),
 249                            PXA_DCMD_STR(ENDIAN), burst, width,
 250                            dcmd & PXA_DCMD_LENGTH);
 251                 phys_desc = desc->ddadr;
 252         }
 253         if (i == max_show)
 254                 seq_printf(s, "[%03d] Desc at %08lx ... max display reached\n",
 255                            i, phys_desc);
 256         else
 257                 seq_printf(s, "[%03d] Desc at %08lx is %s\n",
 258                            i, phys_desc, phys_desc == DDADR_STOP ?
 259                            "DDADR_STOP" : "invalid");
 260
 261         return 0;
 262 }
 263
 264 static int dbg_show_chan_state(struct seq_file *s, void *p)
 265 {
 266         struct pxad_phy *phy = s->private;
 267         u32 dcsr, dcmd;
 268         int burst, width;
 269         static const char * const str_prio[] = {
 270                 "high", "normal", "low", "invalid"
 271         };
 272
 273         dcsr = _phy_readl_relaxed(phy, DCSR);
 274         dcmd = _phy_readl_relaxed(phy, DCMD);
 275         burst = dbg_burst_from_dcmd(dcmd);
 276         width = (1 << ((dcmd >> 14) & 0x3)) >> 1;
 277
 278         seq_printf(s, "DMA channel %d\n", phy->idx);
 279         seq_printf(s, "\tPriority : %s\n",
 280                           str_prio[(phy->idx & 0xf) / 4]);
 281         seq_printf(s, "\tUnaligned transfer bit: %s\n",
 282                           _phy_readl_relaxed(phy, DALGN) & BIT(phy->idx) ?
 283                           "yes" : "no");
 284         seq_printf(s, "\tDCSR  = %08x (%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s)\n",
 285                    dcsr, PXA_DCSR_STR(RUN), PXA_DCSR_STR(NODESC),
 286                    PXA_DCSR_STR(STOPIRQEN), PXA_DCSR_STR(EORIRQEN),
 287                    PXA_DCSR_STR(EORJMPEN), PXA_DCSR_STR(EORSTOPEN),
 288                    PXA_DCSR_STR(SETCMPST), PXA_DCSR_STR(CLRCMPST),
 289                    PXA_DCSR_STR(CMPST), PXA_DCSR_STR(EORINTR),
 290                    PXA_DCSR_STR(REQPEND), PXA_DCSR_STR(STOPSTATE),
 291                    PXA_DCSR_STR(ENDINTR), PXA_DCSR_STR(STARTINTR),
 292                    PXA_DCSR_STR(BUSERR));
 293
 294         seq_printf(s, "\tDCMD  = %08x (%s%s%s%s%s%s%sburst=%d width=%d len=%d)\n",
 295                    dcmd,
 296                    PXA_DCMD_STR(INCSRCADDR), PXA_DCMD_STR(INCTRGADDR),
 297                    PXA_DCMD_STR(FLOWSRC), PXA_DCMD_STR(FLOWTRG),
 298                    PXA_DCMD_STR(STARTIRQEN), PXA_DCMD_STR(ENDIRQEN),
 299                    PXA_DCMD_STR(ENDIAN), burst, width, dcmd & PXA_DCMD_LENGTH);
 300         seq_printf(s, "\tDSADR = %08x\n", _phy_readl_relaxed(phy, DSADR));
 301         seq_printf(s, "\tDTADR = %08x\n", _phy_readl_relaxed(phy, DTADR));
 302         seq_printf(s, "\tDDADR = %08x\n", _phy_readl_relaxed(phy, DDADR));
 303
 304         return 0;
 305 }
 306
 307 static int dbg_show_state(struct seq_file *s, void *p)
 308 {
 309         struct pxad_device *pdev = s->private;
 310
 311         /* basic device status */
 312         seq_puts(s, "DMA engine status\n");
 313         seq_printf(s, "\tChannel number: %d\n", pdev->nr_chans);
 314
 315         return 0;
 316 }
 317
 318 #define DBGFS_FUNC_DECL(name) \
 319 static int dbg_open_##name(struct inode *inode, struct file *file) \
 320 { \
 321         return single_open(file, dbg_show_##name, inode->i_private); \
 322 } \
 323 static const struct file_operations dbg_fops_##name = { \
 324         .open           = dbg_open_##name, \
 325         .llseek         = seq_lseek, \
 326         .read           = seq_read, \
 327         .release        = single_release, \
 328 }
 329
 330 DBGFS_FUNC_DECL(state);
 331 DBGFS_FUNC_DECL(chan_state);
 332 DBGFS_FUNC_DECL(descriptors);
 333 DBGFS_FUNC_DECL(requester_chan);
 334
 335 static struct dentry *pxad_dbg_alloc_chan(struct pxad_device *pdev,
 336                                              int ch, struct dentry *chandir)
 337 {
 338         char chan_name[11];
 339         struct dentry *chan, *chan_state = NULL, *chan_descr = NULL;
 340         struct dentry *chan_reqs = NULL;
 341         void *dt;
 342
 343         scnprintf(chan_name, sizeof(chan_name), "%d", ch);
 344         chan = debugfs_create_dir(chan_name, chandir);
 345         dt = (void *)&pdev->phys[ch];
 346
 347         if (chan)
 348                 chan_state = debugfs_create_file("state", 0400, chan, dt,
 349                                                  &dbg_fops_chan_state);
 350         if (chan_state)
 351                 chan_descr = debugfs_create_file("descriptors", 0400, chan, dt,
 352                                                  &dbg_fops_descriptors);
 353         if (chan_descr)
 354                 chan_reqs = debugfs_create_file("requesters", 0400, chan, dt,
 355                                                 &dbg_fops_requester_chan);
 356         if (!chan_reqs)
 357                 goto err_state;
 358
 359         return chan;
 360
 361 err_state:
 362         debugfs_remove_recursive(chan);
 363         return NULL;
 364 }
 365
 366 static void pxad_init_debugfs(struct pxad_device *pdev)
 367 {
 368         int i;
 369         struct dentry *chandir;
 370
 371         pdev->dbgfs_root = debugfs_create_dir(dev_name(pdev->slave.dev), NULL);
 372         if (IS_ERR(pdev->dbgfs_root) || !pdev->dbgfs_root)
 373                 goto err_root;
 374
 375         pdev->dbgfs_state = debugfs_create_file("state", 0400, pdev->dbgfs_root,
 376                                                 pdev, &dbg_fops_state);
 377         if (!pdev->dbgfs_state)
 378                 goto err_state;
 379
 380         pdev->dbgfs_chan =
 381                 kmalloc_array(pdev->nr_chans, sizeof(*pdev->dbgfs_state),
 382                               GFP_KERNEL);
 383         if (!pdev->dbgfs_chan)
 384                 goto err_alloc;
 385
 386         chandir = debugfs_create_dir("channels", pdev->dbgfs_root);
 387         if (!chandir)
 388                 goto err_chandir;
 389
 390         for (i = 0; i < pdev->nr_chans; i++) {
 391                 pdev->dbgfs_chan[i] = pxad_dbg_alloc_chan(pdev, i, chandir);
 392                 if (!pdev->dbgfs_chan[i])
 393                         goto err_chans;
 394         }
 395
 396         return;
 397 err_chans:
 398 err_chandir:
 399         kfree(pdev->dbgfs_chan);
 400 err_alloc:
 401 err_state:
 402         debugfs_remove_recursive(pdev->dbgfs_root);
 403 err_root:
 404         pr_err("pxad: debugfs is not available\n");
 405 }
 406
 407 static void pxad_cleanup_debugfs(struct pxad_device *pdev)
 408 {
 409         debugfs_remove_recursive(pdev->dbgfs_root);
 410 }
 411 #else
 412 static inline void pxad_init_debugfs(struct pxad_device *pdev) {}
 413 static inline void pxad_cleanup_debugfs(struct pxad_device *pdev) {}
 414 #endif
 415
 416 /*
 417  * In the transition phase where legacy pxa handling is done at the same time as
 418  * mmp_dma, the DMA physical channel split between the 2 DMA providers is done
 419  * through legacy_reserved. Legacy code reserves DMA channels by settings
 420  * corresponding bits in legacy_reserved.
 421  */
 422 static u32 legacy_reserved;
 423 static u32 legacy_unavailable;
 424
 425 static struct pxad_phy *lookup_phy(struct pxad_chan *pchan)
 426 {
 427         int prio, i;
 428         struct pxad_device *pdev = to_pxad_dev(pchan->vc.chan.device);
 429         struct pxad_phy *phy, *found = NULL;
 430         unsigned long flags;
 431
 432         /*
 433          * dma channel priorities
 434          * ch 0 - 3,  16 - 19  <--> (0)
 435          * ch 4 - 7,  20 - 23  <--> (1)
 436          * ch 8 - 11, 24 - 27  <--> (2)
 437          * ch 12 - 15, 28 - 31  <--> (3)
 438          */
 439
 440         spin_lock_irqsave(&pdev->phy_lock, flags);
 441         for (prio = pchan->prio; prio >= PXAD_PRIO_HIGHEST; prio--) {
 442                 for (i = 0; i < pdev->nr_chans; i++) {
 443                         if (prio != (i & 0xf) >> 2)
 444                                 continue;
 445                         if ((i < 32) && (legacy_reserved & BIT(i)))
 446                                 continue;
 447                         phy = &pdev->phys[i];
 448                         if (!phy->vchan) {
 449                                 phy->vchan = pchan;
 450                                 found = phy;
 451                                 if (i < 32)
 452                                         legacy_unavailable |= BIT(i);
 453                                 goto out_unlock;
 454                         }
 455                 }
 456         }
 457
 458 out_unlock:
 459         spin_unlock_irqrestore(&pdev->phy_lock, flags);
 460         dev_dbg(&pchan->vc.chan.dev->device,
 461                 "%s(): phy=%p(%d)\n", __func__, found,
 462                 found ? found->idx : -1);
 463
 464         return found;
 465 }
 466
 467 static void pxad_free_phy(struct pxad_chan *chan)
 468 {
 469         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
 470         unsigned long flags;
 471         u32 reg;
 472         int i;
 473
 474         dev_dbg(&chan->vc.chan.dev->device,
 475                 "%s(): freeing\n", __func__);
 476         if (!chan->phy)
 477                 return;
 478
 479         /* clear the channel mapping in DRCMR */
 480         if (chan->drcmr <= pdev->nr_requestors) {
 481                 reg = pxad_drcmr(chan->drcmr);
 482                 writel_relaxed(0, chan->phy->base + reg);
 483         }
 484
 485         spin_lock_irqsave(&pdev->phy_lock, flags);
 486         for (i = 0; i < 32; i++)
 487                 if (chan->phy == &pdev->phys[i])
 488                         legacy_unavailable &= ~BIT(i);
 489         chan->phy->vchan = NULL;
 490         chan->phy = NULL;
 491         spin_unlock_irqrestore(&pdev->phy_lock, flags);
 492 }
 493
 494 static bool is_chan_running(struct pxad_chan *chan)
 495 {
 496         u32 dcsr;
 497         struct pxad_phy *phy = chan->phy;
 498
 499         if (!phy)
 500                 return false;
 501         dcsr = phy_readl_relaxed(phy, DCSR);
 502         return dcsr & PXA_DCSR_RUN;
 503 }
 504
 505 static bool is_running_chan_misaligned(struct pxad_chan *chan)
 506 {
 507         u32 dalgn;
 508
 509         BUG_ON(!chan->phy);
 510         dalgn = phy_readl_relaxed(chan->phy, DALGN);
 511         return dalgn & (BIT(chan->phy->idx));
 512 }
 513
 514 static void phy_enable(struct pxad_phy *phy, bool misaligned)
 515 {
 516         struct pxad_device *pdev;
 517         u32 reg, dalgn;
 518
 519         if (!phy->vchan)
 520                 return;
 521
 522         dev_dbg(&phy->vchan->vc.chan.dev->device,
 523                 "%s(); phy=%p(%d) misaligned=%d\n", __func__,
 524                 phy, phy->idx, misaligned);
 525
 526         pdev = to_pxad_dev(phy->vchan->vc.chan.device);
 527         if (phy->vchan->drcmr <= pdev->nr_requestors) {
 528                 reg = pxad_drcmr(phy->vchan->drcmr);
 529                 writel_relaxed(DRCMR_MAPVLD | phy->idx, phy->base + reg);
 530         }
 531
 532         dalgn = phy_readl_relaxed(phy, DALGN);
 533         if (misaligned)
 534                 dalgn |= BIT(phy->idx);
 535         else
 536                 dalgn &= ~BIT(phy->idx);
 537         phy_writel_relaxed(phy, dalgn, DALGN);
 538
 539         phy_writel(phy, PXA_DCSR_STOPIRQEN | PXA_DCSR_ENDINTR |
 540                    PXA_DCSR_BUSERR | PXA_DCSR_RUN, DCSR);
 541 }
 542
 543 static void phy_disable(struct pxad_phy *phy)
 544 {
 545         u32 dcsr;
 546
 547         if (!phy)
 548                 return;
 549
 550         dcsr = phy_readl_relaxed(phy, DCSR);
 551         dev_dbg(&phy->vchan->vc.chan.dev->device,
 552                 "%s(): phy=%p(%d)\n", __func__, phy, phy->idx);
 553         phy_writel(phy, dcsr & ~PXA_DCSR_RUN & ~PXA_DCSR_STOPIRQEN, DCSR);
 554 }
 555
 556 static void pxad_launch_chan(struct pxad_chan *chan,
 557                                  struct pxad_desc_sw *desc)
 558 {
 559         dev_dbg(&chan->vc.chan.dev->device,
 560                 "%s(): desc=%p\n", __func__, desc);
 561         if (!chan->phy) {
 562                 chan->phy = lookup_phy(chan);
 563                 if (!chan->phy) {
 564                         dev_dbg(&chan->vc.chan.dev->device,
 565                                 "%s(): no free dma channel\n", __func__);
 566                         return;
 567                 }
 568         }
 569         chan->bus_error = 0;
 570
 571         /*
 572          * Program the descriptor's address into the DMA controller,
 573          * then start the DMA transaction
 574          */
 575         phy_writel(chan->phy, desc->first, DDADR);
 576         phy_enable(chan->phy, chan->misaligned);
 577         wake_up(&chan->wq_state);
 578 }
 579
 580 static void set_updater_desc(struct pxad_desc_sw *sw_desc,
 581                              unsigned long flags)
 582 {
 583         struct pxad_desc_hw *updater =
 584                 sw_desc->hw_desc[sw_desc->nb_desc - 1];
 585         dma_addr_t dma = sw_desc->hw_desc[sw_desc->nb_desc - 2]->ddadr;
 586
 587         updater->ddadr = DDADR_STOP;
 588         updater->dsadr = dma;
 589         updater->dtadr = dma + 8;
 590         updater->dcmd = PXA_DCMD_WIDTH4 | PXA_DCMD_BURST32 |
 591                 (PXA_DCMD_LENGTH & sizeof(u32));
 592         if (flags & DMA_PREP_INTERRUPT)
 593                 updater->dcmd |= PXA_DCMD_ENDIRQEN;
 594         if (sw_desc->cyclic)
 595                 sw_desc->hw_desc[sw_desc->nb_desc - 2]->ddadr = sw_desc->first;
 596 }
 597
 598 static bool is_desc_completed(struct virt_dma_desc *vd)
 599 {
 600         struct pxad_desc_sw *sw_desc = to_pxad_sw_desc(vd);
 601         struct pxad_desc_hw *updater =
 602                 sw_desc->hw_desc[sw_desc->nb_desc - 1];
 603
 604         return updater->dtadr != (updater->dsadr + 8);
 605 }
 606
 607 static void pxad_desc_chain(struct virt_dma_desc *vd1,
 608                                 struct virt_dma_desc *vd2)
 609 {
 610         struct pxad_desc_sw *desc1 = to_pxad_sw_desc(vd1);
 611         struct pxad_desc_sw *desc2 = to_pxad_sw_desc(vd2);
 612         dma_addr_t dma_to_chain;
 613
 614         dma_to_chain = desc2->first;
 615         desc1->hw_desc[desc1->nb_desc - 1]->ddadr = dma_to_chain;
 616 }
 617
 618 static bool pxad_try_hotchain(struct virt_dma_chan *vc,
 619                                   struct virt_dma_desc *vd)
 620 {
 621         struct virt_dma_desc *vd_last_issued = NULL;
 622         struct pxad_chan *chan = to_pxad_chan(&vc->chan);
 623
 624         /*
 625          * Attempt to hot chain the tx if the phy is still running. This is
 626          * considered successful only if either the channel is still running
 627          * after the chaining, or if the chained transfer is completed after
 628          * having been hot chained.
 629          * A change of alignment is not allowed, and forbids hotchaining.
 630          */
 631         if (is_chan_running(chan)) {
 632                 BUG_ON(list_empty(&vc->desc_issued));
 633
 634                 if (!is_running_chan_misaligned(chan) &&
 635                     to_pxad_sw_desc(vd)->misaligned)
 636                         return false;
 637
 638                 vd_last_issued = list_entry(vc->desc_issued.prev,
 639                                             struct virt_dma_desc, node);
 640                 pxad_desc_chain(vd_last_issued, vd);
 641                 if (is_chan_running(chan) || is_desc_completed(vd))
 642                         return true;
 643         }
 644
 645         return false;
 646 }
 647
 648 static unsigned int clear_chan_irq(struct pxad_phy *phy)
 649 {
 650         u32 dcsr;
 651         u32 dint = readl(phy->base + DINT);
 652
 653         if (!(dint & BIT(phy->idx)))
 654                 return PXA_DCSR_RUN;
 655
 656         /* clear irq */
 657         dcsr = phy_readl_relaxed(phy, DCSR);
 658         phy_writel(phy, dcsr, DCSR);
 659         if ((dcsr & PXA_DCSR_BUSERR) && (phy->vchan))
 660                 dev_warn(&phy->vchan->vc.chan.dev->device,
 661                          "%s(chan=%p): PXA_DCSR_BUSERR\n",
 662                          __func__, &phy->vchan);
 663
 664         return dcsr & ~PXA_DCSR_RUN;
 665 }
 666
 667 static irqreturn_t pxad_chan_handler(int irq, void *dev_id)
 668 {
 669         struct pxad_phy *phy = dev_id;
 670         struct pxad_chan *chan = phy->vchan;
 671         struct virt_dma_desc *vd, *tmp;
 672         unsigned int dcsr;
 673         unsigned long flags;
 674         bool vd_completed;
 675         dma_cookie_t last_started = 0;
 676
 677         BUG_ON(!chan);
 678
 679         dcsr = clear_chan_irq(phy);
 680         if (dcsr & PXA_DCSR_RUN)
 681                 return IRQ_NONE;
 682
 683         spin_lock_irqsave(&chan->vc.lock, flags);
 684         list_for_each_entry_safe(vd, tmp, &chan->vc.desc_issued, node) {
 685                 vd_completed = is_desc_completed(vd);
 686                 dev_dbg(&chan->vc.chan.dev->device,
 687                         "%s(): checking txd %p[%x]: completed=%d dcsr=0x%x\n",
 688                         __func__, vd, vd->tx.cookie, vd_completed,
 689                         dcsr);
 690                 last_started = vd->tx.cookie;
 691                 if (to_pxad_sw_desc(vd)->cyclic) {
 692                         vchan_cyclic_callback(vd);
 693                         break;
 694                 }
 695                 if (vd_completed) {
 696                         list_del(&vd->node);
 697                         vchan_cookie_complete(vd);
 698                 } else {
 699                         break;
 700                 }
 701         }
 702
 703         if (dcsr & PXA_DCSR_BUSERR) {
 704                 chan->bus_error = last_started;
 705                 phy_disable(phy);
 706         }
 707
 708         if (!chan->bus_error && dcsr & PXA_DCSR_STOPSTATE) {
 709                 dev_dbg(&chan->vc.chan.dev->device,
 710                 "%s(): channel stopped, submitted_empty=%d issued_empty=%d",
 711                         __func__,
 712                         list_empty(&chan->vc.desc_submitted),
 713                         list_empty(&chan->vc.desc_issued));
 714                 phy_writel_relaxed(phy, dcsr & ~PXA_DCSR_STOPIRQEN, DCSR);
 715
 716                 if (list_empty(&chan->vc.desc_issued)) {
 717                         chan->misaligned =
 718                                 !list_empty(&chan->vc.desc_submitted);
 719                 } else {
 720                         vd = list_first_entry(&chan->vc.desc_issued,
 721                                               struct virt_dma_desc, node);
 722                         pxad_launch_chan(chan, to_pxad_sw_desc(vd));
 723                 }
 724         }
 725         spin_unlock_irqrestore(&chan->vc.lock, flags);
 726         wake_up(&chan->wq_state);
 727
 728         return IRQ_HANDLED;
 729 }
 730
 731 static irqreturn_t pxad_int_handler(int irq, void *dev_id)
 732 {
 733         struct pxad_device *pdev = dev_id;
 734         struct pxad_phy *phy;
 735         u32 dint = readl(pdev->base + DINT);
 736         int i, ret = IRQ_NONE;
 737
 738         while (dint) {
 739                 i = __ffs(dint);
 740                 dint &= (dint - 1);
 741                 phy = &pdev->phys[i];
 742                 if ((i < 32) && (legacy_reserved & BIT(i)))
 743                         continue;
 744                 if (pxad_chan_handler(irq, phy) == IRQ_HANDLED)
 745                         ret = IRQ_HANDLED;
 746         }
 747
 748         return ret;
 749 }
 750
 751 static int pxad_alloc_chan_resources(struct dma_chan *dchan)
 752 {
 753         struct pxad_chan *chan = to_pxad_chan(dchan);
 754         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
 755
 756         if (chan->desc_pool)
 757                 return 1;
 758
 759         chan->desc_pool = dma_pool_create(dma_chan_name(dchan),
 760                                           pdev->slave.dev,
 761                                           sizeof(struct pxad_desc_hw),
 762                                           __alignof__(struct pxad_desc_hw),
 763                                           0);
 764         if (!chan->desc_pool) {
 765                 dev_err(&chan->vc.chan.dev->device,
 766                         "%s(): unable to allocate descriptor pool\n",
 767                         __func__);
 768                 return -ENOMEM;
 769         }
 770
 771         return 1;
 772 }
 773
 774 static void pxad_free_chan_resources(struct dma_chan *dchan)
 775 {
 776         struct pxad_chan *chan = to_pxad_chan(dchan);
 777
 778         vchan_free_chan_resources(&chan->vc);
 779         dma_pool_destroy(chan->desc_pool);
 780         chan->desc_pool = NULL;
 781
 782 }
 783
 784 static void pxad_free_desc(struct virt_dma_desc *vd)
 785 {
 786         int i;
 787         dma_addr_t dma;
 788         struct pxad_desc_sw *sw_desc = to_pxad_sw_desc(vd);
 789
 790         BUG_ON(sw_desc->nb_desc == 0);
 791         for (i = sw_desc->nb_desc - 1; i >= 0; i--) {
 792                 if (i > 0)
 793                         dma = sw_desc->hw_desc[i - 1]->ddadr;
 794                 else
 795                         dma = sw_desc->first;
 796                 dma_pool_free(sw_desc->desc_pool,
 797                               sw_desc->hw_desc[i], dma);
 798         }
 799         sw_desc->nb_desc = 0;
 800         kfree(sw_desc);
 801 }
 802
 803 static struct pxad_desc_sw *
 804 pxad_alloc_desc(struct pxad_chan *chan, unsigned int nb_hw_desc)
 805 {
 806         struct pxad_desc_sw *sw_desc;
 807         dma_addr_t dma;
 808         int i;
 809
 810         sw_desc = kzalloc(sizeof(*sw_desc) +
 811                           nb_hw_desc * sizeof(struct pxad_desc_hw *),
 812                           GFP_NOWAIT);
 813         if (!sw_desc)
 814                 return NULL;
 815         sw_desc->desc_pool = chan->desc_pool;
 816
 817         for (i = 0; i < nb_hw_desc; i++) {
 818                 sw_desc->hw_desc[i] = dma_pool_alloc(sw_desc->desc_pool,
 819                                                      GFP_NOWAIT, &dma);
 820                 if (!sw_desc->hw_desc[i]) {
 821                         dev_err(&chan->vc.chan.dev->device,
 822                                 "%s(): Couldn't allocate the %dth hw_desc from dma_pool %p\n",
 823                                 __func__, i, sw_desc->desc_pool);
 824                         goto err;
 825                 }
 826
 827                 if (i == 0)
 828                         sw_desc->first = dma;
 829                 else
 830                         sw_desc->hw_desc[i - 1]->ddadr = dma;
 831                 sw_desc->nb_desc++;
 832         }
 833
 834         return sw_desc;
 835 err:
 836         pxad_free_desc(&sw_desc->vd);
 837         return NULL;
 838 }
 839
 840 static dma_cookie_t pxad_tx_submit(struct dma_async_tx_descriptor *tx)
 841 {
 842         struct virt_dma_chan *vc = to_virt_chan(tx->chan);
 843         struct pxad_chan *chan = to_pxad_chan(&vc->chan);
 844         struct virt_dma_desc *vd_chained = NULL,
 845                 *vd = container_of(tx, struct virt_dma_desc, tx);
 846         dma_cookie_t cookie;
 847         unsigned long flags;
 848
 849         set_updater_desc(to_pxad_sw_desc(vd), tx->flags);
 850
 851         spin_lock_irqsave(&vc->lock, flags);
 852         cookie = dma_cookie_assign(tx);
 853
 854         if (list_empty(&vc->desc_submitted) && pxad_try_hotchain(vc, vd)) {
 855                 list_move_tail(&vd->node, &vc->desc_issued);
 856                 dev_dbg(&chan->vc.chan.dev->device,
 857                         "%s(): txd %p[%x]: submitted (hot linked)\n",
 858                         __func__, vd, cookie);
 859                 goto out;
 860         }
 861
 862         /*
 863          * Fallback to placing the tx in the submitted queue
 864          */
 865         if (!list_empty(&vc->desc_submitted)) {
 866                 vd_chained = list_entry(vc->desc_submitted.prev,
 867                                         struct virt_dma_desc, node);
 868                 /*
 869                  * Only chain the descriptors if no new misalignment is
 870                  * introduced. If a new misalignment is chained, let the channel
 871                  * stop, and be relaunched in misalign mode from the irq
 872                  * handler.
 873                  */
 874                 if (chan->misaligned || !to_pxad_sw_desc(vd)->misaligned)
 875                         pxad_desc_chain(vd_chained, vd);
 876                 else
 877                         vd_chained = NULL;
 878         }
 879         dev_dbg(&chan->vc.chan.dev->device,
 880                 "%s(): txd %p[%x]: submitted (%s linked)\n",
 881                 __func__, vd, cookie, vd_chained ? "cold" : "not");
 882         list_move_tail(&vd->node, &vc->desc_submitted);
 883         chan->misaligned |= to_pxad_sw_desc(vd)->misaligned;
 884
 885 out:
 886         spin_unlock_irqrestore(&vc->lock, flags);
 887         return cookie;
 888 }
 889
 890 static void pxad_issue_pending(struct dma_chan *dchan)
 891 {
 892         struct pxad_chan *chan = to_pxad_chan(dchan);
 893         struct virt_dma_desc *vd_first;
 894         unsigned long flags;
 895
 896         spin_lock_irqsave(&chan->vc.lock, flags);
 897         if (list_empty(&chan->vc.desc_submitted))
 898                 goto out;
 899
 900         vd_first = list_first_entry(&chan->vc.desc_submitted,
 901                                     struct virt_dma_desc, node);
 902         dev_dbg(&chan->vc.chan.dev->device,
 903                 "%s(): txd %p[%x]", __func__, vd_first, vd_first->tx.cookie);
 904
 905         vchan_issue_pending(&chan->vc);
 906         if (!pxad_try_hotchain(&chan->vc, vd_first))
 907                 pxad_launch_chan(chan, to_pxad_sw_desc(vd_first));
 908 out:
 909         spin_unlock_irqrestore(&chan->vc.lock, flags);
 910 }
 911
 912 static inline struct dma_async_tx_descriptor *
 913 pxad_tx_prep(struct virt_dma_chan *vc, struct virt_dma_desc *vd,
 914                  unsigned long tx_flags)
 915 {
 916         struct dma_async_tx_descriptor *tx;
 917         struct pxad_chan *chan = container_of(vc, struct pxad_chan, vc);
 918
 919         INIT_LIST_HEAD(&vd->node);
 920         tx = vchan_tx_prep(vc, vd, tx_flags);
 921         tx->tx_submit = pxad_tx_submit;
 922         dev_dbg(&chan->vc.chan.dev->device,
 923                 "%s(): vc=%p txd=%p[%x] flags=0x%lx\n", __func__,
 924                 vc, vd, vd->tx.cookie,
 925                 tx_flags);
 926
 927         return tx;
 928 }
 929
 930 static void pxad_get_config(struct pxad_chan *chan,
 931                             enum dma_transfer_direction dir,
 932                             u32 *dcmd, u32 *dev_src, u32 *dev_dst)
 933 {
 934         u32 maxburst = 0, dev_addr = 0;
 935         enum dma_slave_buswidth width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
 936         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
 937
 938         *dcmd = 0;
 939         if (dir == DMA_DEV_TO_MEM) {
 940                 maxburst = chan->cfg.src_maxburst;
 941                 width = chan->cfg.src_addr_width;
 942                 dev_addr = chan->cfg.src_addr;
 943                 *dev_src = dev_addr;
 944                 *dcmd |= PXA_DCMD_INCTRGADDR;
 945                 if (chan->drcmr <= pdev->nr_requestors)
 946                         *dcmd |= PXA_DCMD_FLOWSRC;
 947         }
 948         if (dir == DMA_MEM_TO_DEV) {
 949                 maxburst = chan->cfg.dst_maxburst;
 950                 width = chan->cfg.dst_addr_width;
 951                 dev_addr = chan->cfg.dst_addr;
 952                 *dev_dst = dev_addr;
 953                 *dcmd |= PXA_DCMD_INCSRCADDR;
 954                 if (chan->drcmr <= pdev->nr_requestors)
 955                         *dcmd |= PXA_DCMD_FLOWTRG;
 956         }
 957         if (dir == DMA_MEM_TO_MEM)
 958                 *dcmd |= PXA_DCMD_BURST32 | PXA_DCMD_INCTRGADDR |
 959                         PXA_DCMD_INCSRCADDR;
 960
 961         dev_dbg(&chan->vc.chan.dev->device,
 962                 "%s(): dev_addr=0x%x maxburst=%d width=%d  dir=%d\n",
 963                 __func__, dev_addr, maxburst, width, dir);
 964
 965         if (width == DMA_SLAVE_BUSWIDTH_1_BYTE)
 966                 *dcmd |= PXA_DCMD_WIDTH1;
 967         else if (width == DMA_SLAVE_BUSWIDTH_2_BYTES)
 968                 *dcmd |= PXA_DCMD_WIDTH2;
 969         else if (width == DMA_SLAVE_BUSWIDTH_4_BYTES)
 970                 *dcmd |= PXA_DCMD_WIDTH4;
 971
 972         if (maxburst == 8)
 973                 *dcmd |= PXA_DCMD_BURST8;
 974         else if (maxburst == 16)
 975                 *dcmd |= PXA_DCMD_BURST16;
 976         else if (maxburst == 32)
 977                 *dcmd |= PXA_DCMD_BURST32;
 978
 979         /* FIXME: drivers should be ported over to use the filter
 980          * function. Once that's done, the following two lines can
 981          * be removed.
 982          */
 983         if (chan->cfg.slave_id)
 984                 chan->drcmr = chan->cfg.slave_id;
 985 }
 986
 987 static struct dma_async_tx_descriptor *
 988 pxad_prep_memcpy(struct dma_chan *dchan,
 989                  dma_addr_t dma_dst, dma_addr_t dma_src,
 990                  size_t len, unsigned long flags)
 991 {
 992         struct pxad_chan *chan = to_pxad_chan(dchan);
 993         struct pxad_desc_sw *sw_desc;
 994         struct pxad_desc_hw *hw_desc;
 995         u32 dcmd;
 996         unsigned int i, nb_desc = 0;
 997         size_t copy;
 998
 999         if (!dchan || !len)
1000                 return NULL;
1001
1002         dev_dbg(&chan->vc.chan.dev->device,
1003                 "%s(): dma_dst=0x%lx dma_src=0x%lx len=%zu flags=%lx\n",
1004                 __func__, (unsigned long)dma_dst, (unsigned long)dma_src,
1005                 len, flags);
1006         pxad_get_config(chan, DMA_MEM_TO_MEM, &dcmd, NULL, NULL);
1007
1008         nb_desc = DIV_ROUND_UP(len, PDMA_MAX_DESC_BYTES);
1009         sw_desc = pxad_alloc_desc(chan, nb_desc + 1);
1010         if (!sw_desc)
1011                 return NULL;
1012         sw_desc->len = len;
1013
1014         if (!IS_ALIGNED(dma_src, 1 << PDMA_ALIGNMENT) ||
1015             !IS_ALIGNED(dma_dst, 1 << PDMA_ALIGNMENT))
1016                 sw_desc->misaligned = true;
1017
1018         i = 0;
1019         do {
1020                 hw_desc = sw_desc->hw_desc[i++];
1021                 copy = min_t(size_t, len, PDMA_MAX_DESC_BYTES);
1022                 hw_desc->dcmd = dcmd | (PXA_DCMD_LENGTH & copy);
1023                 hw_desc->dsadr = dma_src;
1024                 hw_desc->dtadr = dma_dst;
1025                 len -= copy;
1026                 dma_src += copy;
1027                 dma_dst += copy;
1028         } while (len);
1029         set_updater_desc(sw_desc, flags);
1030
1031         return pxad_tx_prep(&chan->vc, &sw_desc->vd, flags);
1032 }
1033
1034 static struct dma_async_tx_descriptor *
1035 pxad_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
1036                    unsigned int sg_len, enum dma_transfer_direction dir,
1037                    unsigned long flags, void *context)
1038 {
1039         struct pxad_chan *chan = to_pxad_chan(dchan);
1040         struct pxad_desc_sw *sw_desc;
1041         size_t len, avail;
1042         struct scatterlist *sg;
1043         dma_addr_t dma;
1044         u32 dcmd, dsadr = 0, dtadr = 0;
1045         unsigned int nb_desc = 0, i, j = 0;
1046
1047         if ((sgl == NULL) || (sg_len == 0))
1048                 return NULL;
1049
1050         pxad_get_config(chan, dir, &dcmd, &dsadr, &dtadr);
1051         dev_dbg(&chan->vc.chan.dev->device,
1052                 "%s(): dir=%d flags=%lx\n", __func__, dir, flags);
1053
1054         for_each_sg(sgl, sg, sg_len, i)
1055                 nb_desc += DIV_ROUND_UP(sg_dma_len(sg), PDMA_MAX_DESC_BYTES);
1056         sw_desc = pxad_alloc_desc(chan, nb_desc + 1);
1057         if (!sw_desc)
1058                 return NULL;
1059
1060         for_each_sg(sgl, sg, sg_len, i) {
1061                 dma = sg_dma_address(sg);
1062                 avail = sg_dma_len(sg);
1063                 sw_desc->len += avail;
1064
1065                 do {
1066                         len = min_t(size_t, avail, PDMA_MAX_DESC_BYTES);
1067                         if (dma & 0x7)
1068                                 sw_desc->misaligned = true;
1069
1070                         sw_desc->hw_desc[j]->dcmd =
1071                                 dcmd | (PXA_DCMD_LENGTH & len);
1072                         sw_desc->hw_desc[j]->dsadr = dsadr ? dsadr : dma;
1073                         sw_desc->hw_desc[j++]->dtadr = dtadr ? dtadr : dma;
1074
1075                         dma += len;
1076                         avail -= len;
1077                 } while (avail);
1078         }
1079         set_updater_desc(sw_desc, flags);
1080
1081         return pxad_tx_prep(&chan->vc, &sw_desc->vd, flags);
1082 }
1083
1084 static struct dma_async_tx_descriptor *
1085 pxad_prep_dma_cyclic(struct dma_chan *dchan,
1086                      dma_addr_t buf_addr, size_t len, size_t period_len,
1087                      enum dma_transfer_direction dir, unsigned long flags)
1088 {
1089         struct pxad_chan *chan = to_pxad_chan(dchan);
1090         struct pxad_desc_sw *sw_desc;
1091         struct pxad_desc_hw **phw_desc;
1092         dma_addr_t dma;
1093         u32 dcmd, dsadr = 0, dtadr = 0;
1094         unsigned int nb_desc = 0;
1095
1096         if (!dchan || !len || !period_len)
1097                 return NULL;
1098         if ((dir != DMA_DEV_TO_MEM) && (dir != DMA_MEM_TO_DEV)) {
1099                 dev_err(&chan->vc.chan.dev->device,
1100                         "Unsupported direction for cyclic DMA\n");
1101                 return NULL;
1102         }
1103         /* the buffer length must be a multiple of period_len */
1104         if (len % period_len != 0 || period_len > PDMA_MAX_DESC_BYTES ||
1105             !IS_ALIGNED(period_len, 1 << PDMA_ALIGNMENT))
1106                 return NULL;
1107
1108         pxad_get_config(chan, dir, &dcmd, &dsadr, &dtadr);
1109         dcmd |= PXA_DCMD_ENDIRQEN | (PXA_DCMD_LENGTH & period_len);
1110         dev_dbg(&chan->vc.chan.dev->device,
1111                 "%s(): buf_addr=0x%lx len=%zu period=%zu dir=%d flags=%lx\n",
1112                 __func__, (unsigned long)buf_addr, len, period_len, dir, flags);
1113
1114         nb_desc = DIV_ROUND_UP(period_len, PDMA_MAX_DESC_BYTES);
1115         nb_desc *= DIV_ROUND_UP(len, period_len);
1116         sw_desc = pxad_alloc_desc(chan, nb_desc + 1);
1117         if (!sw_desc)
1118                 return NULL;
1119         sw_desc->cyclic = true;
1120         sw_desc->len = len;
1121
1122         phw_desc = sw_desc->hw_desc;
1123         dma = buf_addr;
1124         do {
1125                 phw_desc[0]->dsadr = dsadr ? dsadr : dma;
1126                 phw_desc[0]->dtadr = dtadr ? dtadr : dma;
1127                 phw_desc[0]->dcmd = dcmd;
1128                 phw_desc++;
1129                 dma += period_len;
1130                 len -= period_len;
1131         } while (len);
1132         set_updater_desc(sw_desc, flags);
1133
1134         return pxad_tx_prep(&chan->vc, &sw_desc->vd, flags);
1135 }
1136
1137 static int pxad_config(struct dma_chan *dchan,
1138                        struct dma_slave_config *cfg)
1139 {
1140         struct pxad_chan *chan = to_pxad_chan(dchan);
1141
1142         if (!dchan)
1143                 return -EINVAL;
1144
1145         chan->cfg = *cfg;
1146         return 0;
1147 }
1148
1149 static int pxad_terminate_all(struct dma_chan *dchan)
1150 {
1151         struct pxad_chan *chan = to_pxad_chan(dchan);
1152         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
1153         struct virt_dma_desc *vd = NULL;
1154         unsigned long flags;
1155         struct pxad_phy *phy;
1156         LIST_HEAD(head);
1157
1158         dev_dbg(&chan->vc.chan.dev->device,
1159                 "%s(): vchan %p: terminate all\n", __func__, &chan->vc);
1160
1161         spin_lock_irqsave(&chan->vc.lock, flags);
1162         vchan_get_all_descriptors(&chan->vc, &head);
1163
1164         list_for_each_entry(vd, &head, node) {
1165                 dev_dbg(&chan->vc.chan.dev->device,
1166                         "%s(): cancelling txd %p[%x] (completed=%d)", __func__,
1167                         vd, vd->tx.cookie, is_desc_completed(vd));
1168         }
1169
1170         phy = chan->phy;
1171         if (phy) {
1172                 phy_disable(chan->phy);
1173                 pxad_free_phy(chan);
1174                 chan->phy = NULL;
1175                 spin_lock(&pdev->phy_lock);
1176                 phy->vchan = NULL;
1177                 spin_unlock(&pdev->phy_lock);
1178         }
1179         spin_unlock_irqrestore(&chan->vc.lock, flags);
1180         vchan_dma_desc_free_list(&chan->vc, &head);
1181
1182         return 0;
1183 }
1184
1185 static unsigned int pxad_residue(struct pxad_chan *chan,
1186                                  dma_cookie_t cookie)
1187 {
1188         struct virt_dma_desc *vd = NULL;
1189         struct pxad_desc_sw *sw_desc = NULL;
1190         struct pxad_desc_hw *hw_desc = NULL;
1191         u32 curr, start, len, end, residue = 0;
1192         unsigned long flags;
1193         bool passed = false;
1194         int i;
1195
1196         /*
1197          * If the channel does not have a phy pointer anymore, it has already
1198          * been completed. Therefore, its residue is 0.
1199          */
1200         if (!chan->phy)
1201                 return 0;
1202
1203         spin_lock_irqsave(&chan->vc.lock, flags);
1204
1205         vd = vchan_find_desc(&chan->vc, cookie);
1206         if (!vd)
1207                 goto out;
1208
1209         sw_desc = to_pxad_sw_desc(vd);
1210         if (sw_desc->hw_desc[0]->dcmd & PXA_DCMD_INCSRCADDR)
1211                 curr = phy_readl_relaxed(chan->phy, DSADR);
1212         else
1213                 curr = phy_readl_relaxed(chan->phy, DTADR);
1214
1215         /*
1216          * curr has to be actually read before checking descriptor
1217          * completion, so that a curr inside a status updater
1218          * descriptor implies the following test returns true, and
1219          * preventing reordering of curr load and the test.
1220          */
1221         rmb();
1222         if (is_desc_completed(vd))
1223                 goto out;
1224
1225         for (i = 0; i < sw_desc->nb_desc - 1; i++) {
1226                 hw_desc = sw_desc->hw_desc[i];
1227                 if (sw_desc->hw_desc[0]->dcmd & PXA_DCMD_INCSRCADDR)
1228                         start = hw_desc->dsadr;
1229                 else
1230                         start = hw_desc->dtadr;
1231                 len = hw_desc->dcmd & PXA_DCMD_LENGTH;
1232                 end = start + len;
1233
1234                 /*
1235                  * 'passed' will be latched once we found the descriptor
1236                  * which lies inside the boundaries of the curr
1237                  * pointer. All descriptors that occur in the list
1238                  * _after_ we found that partially handled descriptor
1239                  * are still to be processed and are hence added to the
1240                  * residual bytes counter.
1241                  */
1242
1243                 if (passed) {
1244                         residue += len;
1245                 } else if (curr >= start && curr <= end) {
1246                         residue += end - curr;
1247                         passed = true;
1248                 }
1249         }
1250         if (!passed)
1251                 residue = sw_desc->len;
1252
1253 out:
1254         spin_unlock_irqrestore(&chan->vc.lock, flags);
1255         dev_dbg(&chan->vc.chan.dev->device,
1256                 "%s(): txd %p[%x] sw_desc=%p: %d\n",
1257                 __func__, vd, cookie, sw_desc, residue);
1258         return residue;
1259 }
1260
1261 static enum dma_status pxad_tx_status(struct dma_chan *dchan,
1262                                       dma_cookie_t cookie,
1263                                       struct dma_tx_state *txstate)
1264 {
1265         struct pxad_chan *chan = to_pxad_chan(dchan);
1266         enum dma_status ret;
1267
1268         if (cookie == chan->bus_error)
1269                 return DMA_ERROR;
1270
1271         ret = dma_cookie_status(dchan, cookie, txstate);
1272         if (likely(txstate && (ret != DMA_ERROR)))
1273                 dma_set_residue(txstate, pxad_residue(chan, cookie));
1274
1275         return ret;
1276 }
1277
1278 static void pxad_synchronize(struct dma_chan *dchan)
1279 {
1280         struct pxad_chan *chan = to_pxad_chan(dchan);
1281
1282         wait_event(chan->wq_state, !is_chan_running(chan));
1283         vchan_synchronize(&chan->vc);
1284 }
1285
1286 static void pxad_free_channels(struct dma_device *dmadev)
1287 {
1288         struct pxad_chan *c, *cn;
1289
1290         list_for_each_entry_safe(c, cn, &dmadev->channels,
1291                                  vc.chan.device_node) {
1292                 list_del(&c->vc.chan.device_node);
1293                 tasklet_kill(&c->vc.task);
1294         }
1295 }
1296
1297 static int pxad_remove(struct platform_device *op)
1298 {
1299         struct pxad_device *pdev = platform_get_drvdata(op);
1300
1301         pxad_cleanup_debugfs(pdev);
1302         pxad_free_channels(&pdev->slave);
1303         dma_async_device_unregister(&pdev->slave);
1304         return 0;
1305 }
1306
1307 static int pxad_init_phys(struct platform_device *op,
1308                           struct pxad_device *pdev,
1309                           unsigned int nb_phy_chans)
1310 {
1311         int irq0, irq, nr_irq = 0, i, ret;
1312         struct pxad_phy *phy;
1313
1314         irq0 = platform_get_irq(op, 0);
1315         if (irq0 < 0)
1316                 return irq0;
1317
1318         pdev->phys = devm_kcalloc(&op->dev, nb_phy_chans,
1319                                   sizeof(pdev->phys[0]), GFP_KERNEL);
1320         if (!pdev->phys)
1321                 return -ENOMEM;
1322
1323         for (i = 0; i < nb_phy_chans; i++)
1324                 if (platform_get_irq(op, i) > 0)
1325                         nr_irq++;
1326
1327         for (i = 0; i < nb_phy_chans; i++) {
1328                 phy = &pdev->phys[i];
1329                 phy->base = pdev->base;
1330                 phy->idx = i;
1331                 irq = platform_get_irq(op, i);
1332                 if ((nr_irq > 1) && (irq > 0))
1333                         ret = devm_request_irq(&op->dev, irq,
1334                                                pxad_chan_handler,
1335                                                IRQF_SHARED, "pxa-dma", phy);
1336                 if ((nr_irq == 1) && (i == 0))
1337                         ret = devm_request_irq(&op->dev, irq0,
1338                                                pxad_int_handler,
1339                                                IRQF_SHARED, "pxa-dma", pdev);
1340                 if (ret) {
1341                         dev_err(pdev->slave.dev,
1342                                 "%s(): can't request irq %d:%d\n", __func__,
1343                                 irq, ret);
1344                         return ret;
1345                 }
1346         }
1347
1348         return 0;
1349 }
1350
1351 static const struct of_device_id pxad_dt_ids[] = {
1352         { .compatible = "marvell,pdma-1.0", },
1353         {}
1354 };
1355 MODULE_DEVICE_TABLE(of, pxad_dt_ids);
1356
1357 static struct dma_chan *pxad_dma_xlate(struct of_phandle_args *dma_spec,
1358                                            struct of_dma *ofdma)
1359 {
1360         struct pxad_device *d = ofdma->of_dma_data;
1361         struct dma_chan *chan;
1362
1363         chan = dma_get_any_slave_channel(&d->slave);
1364         if (!chan)
1365                 return NULL;
1366
1367         to_pxad_chan(chan)->drcmr = dma_spec->args[0];
1368         to_pxad_chan(chan)->prio = dma_spec->args[1];
1369
1370         return chan;
1371 }
1372
1373 static int pxad_init_dmadev(struct platform_device *op,
1374                             struct pxad_device *pdev,
1375                             unsigned int nr_phy_chans,
1376                             unsigned int nr_requestors)
1377 {
1378         int ret;
1379         unsigned int i;
1380         struct pxad_chan *c;
1381
1382         pdev->nr_chans = nr_phy_chans;
1383         pdev->nr_requestors = nr_requestors;
1384         INIT_LIST_HEAD(&pdev->slave.channels);
1385         pdev->slave.device_alloc_chan_resources = pxad_alloc_chan_resources;
1386         pdev->slave.device_free_chan_resources = pxad_free_chan_resources;
1387         pdev->slave.device_tx_status = pxad_tx_status;
1388         pdev->slave.device_issue_pending = pxad_issue_pending;
1389         pdev->slave.device_config = pxad_config;
1390         pdev->slave.device_synchronize = pxad_synchronize;
1391         pdev->slave.device_terminate_all = pxad_terminate_all;
1392
1393         if (op->dev.coherent_dma_mask)
1394                 dma_set_mask(&op->dev, op->dev.coherent_dma_mask);
1395         else
1396                 dma_set_mask(&op->dev, DMA_BIT_MASK(32));
1397
1398         ret = pxad_init_phys(op, pdev, nr_phy_chans);
1399         if (ret)
1400                 return ret;
1401
1402         for (i = 0; i < nr_phy_chans; i++) {
1403                 c = devm_kzalloc(&op->dev, sizeof(*c), GFP_KERNEL);
1404                 if (!c)
1405                         return -ENOMEM;
1406                 c->vc.desc_free = pxad_free_desc;
1407                 vchan_init(&c->vc, &pdev->slave);
1408                 init_waitqueue_head(&c->wq_state);
1409         }
1410
1411         return dma_async_device_register(&pdev->slave);
1412 }
1413
1414 static int pxad_probe(struct platform_device *op)
1415 {
1416         struct pxad_device *pdev;
1417         const struct of_device_id *of_id;
1418         struct mmp_dma_platdata *pdata = dev_get_platdata(&op->dev);
1419         struct resource *iores;
1420         int ret, dma_channels = 0, nb_requestors = 0;
1421         const enum dma_slave_buswidth widths =
1422                 DMA_SLAVE_BUSWIDTH_1_BYTE   | DMA_SLAVE_BUSWIDTH_2_BYTES |
1423                 DMA_SLAVE_BUSWIDTH_4_BYTES;
1424
1425         pdev = devm_kzalloc(&op->dev, sizeof(*pdev), GFP_KERNEL);
1426         if (!pdev)
1427                 return -ENOMEM;
1428
1429         spin_lock_init(&pdev->phy_lock);
1430
1431         iores = platform_get_resource(op, IORESOURCE_MEM, 0);
1432         pdev->base = devm_ioremap_resource(&op->dev, iores);
1433         if (IS_ERR(pdev->base))
1434                 return PTR_ERR(pdev->base);
1435
1436         of_id = of_match_device(pxad_dt_ids, &op->dev);
1437         if (of_id) {
1438                 of_property_read_u32(op->dev.of_node, "#dma-channels",
1439                                      &dma_channels);
1440                 ret = of_property_read_u32(op->dev.of_node, "#dma-requests",
1441                                            &nb_requestors);
1442                 if (ret) {
1443                         dev_warn(pdev->slave.dev,
1444                                  "#dma-requests set to default 32 as missing in OF: %d",
1445                                  ret);
1446                         nb_requestors = 32;
1447                 };
1448         } else if (pdata && pdata->dma_channels) {
1449                 dma_channels = pdata->dma_channels;
1450                 nb_requestors = pdata->nb_requestors;
1451         } else {
1452                 dma_channels = 32;      /* default 32 channel */
1453         }
1454
1455         dma_cap_set(DMA_SLAVE, pdev->slave.cap_mask);
1456         dma_cap_set(DMA_MEMCPY, pdev->slave.cap_mask);
1457         dma_cap_set(DMA_CYCLIC, pdev->slave.cap_mask);
1458         dma_cap_set(DMA_PRIVATE, pdev->slave.cap_mask);
1459         pdev->slave.device_prep_dma_memcpy = pxad_prep_memcpy;
1460         pdev->slave.device_prep_slave_sg = pxad_prep_slave_sg;
1461         pdev->slave.device_prep_dma_cyclic = pxad_prep_dma_cyclic;
1462
1463         pdev->slave.copy_align = PDMA_ALIGNMENT;
1464         pdev->slave.src_addr_widths = widths;
1465         pdev->slave.dst_addr_widths = widths;
1466         pdev->slave.directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
1467         pdev->slave.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
1468         pdev->slave.descriptor_reuse = true;
1469
1470         pdev->slave.dev = &op->dev;
1471         ret = pxad_init_dmadev(op, pdev, dma_channels, nb_requestors);
1472         if (ret) {
1473                 dev_err(pdev->slave.dev, "unable to register\n");
1474                 return ret;
1475         }
1476
1477         if (op->dev.of_node) {
1478                 /* Device-tree DMA controller registration */
1479                 ret = of_dma_controller_register(op->dev.of_node,
1480                                                  pxad_dma_xlate, pdev);
1481                 if (ret < 0) {
1482                         dev_err(pdev->slave.dev,
1483                                 "of_dma_controller_register failed\n");
1484                         return ret;
1485                 }
1486         }
1487
1488         platform_set_drvdata(op, pdev);
1489         pxad_init_debugfs(pdev);
1490         dev_info(pdev->slave.dev, "initialized %d channels on %d requestors\n",
1491                  dma_channels, nb_requestors);
1492         return 0;
1493 }
1494
1495 static const struct platform_device_id pxad_id_table[] = {
1496         { "pxa-dma", },
1497         { },
1498 };
1499
1500 static struct platform_driver pxad_driver = {
1501         .driver         = {
1502                 .name   = "pxa-dma",
1503                 .of_match_table = pxad_dt_ids,
1504         },
1505         .id_table       = pxad_id_table,
1506         .probe          = pxad_probe,
1507         .remove         = pxad_remove,
1508 };
1509
1510 bool pxad_filter_fn(struct dma_chan *chan, void *param)
1511 {
1512         struct pxad_chan *c = to_pxad_chan(chan);
1513         struct pxad_param *p = param;
1514
1515         if (chan->device->dev->driver != &pxad_driver.driver)
1516                 return false;
1517
1518         c->drcmr = p->drcmr;
1519         c->prio = p->prio;
1520
1521         return true;
1522 }
1523 EXPORT_SYMBOL_GPL(pxad_filter_fn);
1524
1525 int pxad_toggle_reserved_channel(int legacy_channel)
1526 {
1527         if (legacy_unavailable & (BIT(legacy_channel)))
1528                 return -EBUSY;
1529         legacy_reserved ^= BIT(legacy_channel);
1530         return 0;
1531 }
1532 EXPORT_SYMBOL_GPL(pxad_toggle_reserved_channel);
1533
1534 module_platform_driver(pxad_driver);
1535
1536 MODULE_DESCRIPTION("Marvell PXA Peripheral DMA Driver");
1537 MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
1538 MODULE_LICENSE("GPL v2");