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 static struct pxad_phy *lookup_phy(struct pxad_chan *pchan)
 417 {
 418         int prio, i;
 419         struct pxad_device *pdev = to_pxad_dev(pchan->vc.chan.device);
 420         struct pxad_phy *phy, *found = NULL;
 421         unsigned long flags;
 422
 423         /*
 424          * dma channel priorities
 425          * ch 0 - 3,  16 - 19  <--> (0)
 426          * ch 4 - 7,  20 - 23  <--> (1)
 427          * ch 8 - 11, 24 - 27  <--> (2)
 428          * ch 12 - 15, 28 - 31  <--> (3)
 429          */
 430
 431         spin_lock_irqsave(&pdev->phy_lock, flags);
 432         for (prio = pchan->prio; prio >= PXAD_PRIO_HIGHEST; prio--) {
 433                 for (i = 0; i < pdev->nr_chans; i++) {
 434                         if (prio != (i & 0xf) >> 2)
 435                                 continue;
 436                         phy = &pdev->phys[i];
 437                         if (!phy->vchan) {
 438                                 phy->vchan = pchan;
 439                                 found = phy;
 440                                 goto out_unlock;
 441                         }
 442                 }
 443         }
 444
 445 out_unlock:
 446         spin_unlock_irqrestore(&pdev->phy_lock, flags);
 447         dev_dbg(&pchan->vc.chan.dev->device,
 448                 "%s(): phy=%p(%d)\n", __func__, found,
 449                 found ? found->idx : -1);
 450
 451         return found;
 452 }
 453
 454 static void pxad_free_phy(struct pxad_chan *chan)
 455 {
 456         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
 457         unsigned long flags;
 458         u32 reg;
 459
 460         dev_dbg(&chan->vc.chan.dev->device,
 461                 "%s(): freeing\n", __func__);
 462         if (!chan->phy)
 463                 return;
 464
 465         /* clear the channel mapping in DRCMR */
 466         if (chan->drcmr <= pdev->nr_requestors) {
 467                 reg = pxad_drcmr(chan->drcmr);
 468                 writel_relaxed(0, chan->phy->base + reg);
 469         }
 470
 471         spin_lock_irqsave(&pdev->phy_lock, flags);
 472         chan->phy->vchan = NULL;
 473         chan->phy = NULL;
 474         spin_unlock_irqrestore(&pdev->phy_lock, flags);
 475 }
 476
 477 static bool is_chan_running(struct pxad_chan *chan)
 478 {
 479         u32 dcsr;
 480         struct pxad_phy *phy = chan->phy;
 481
 482         if (!phy)
 483                 return false;
 484         dcsr = phy_readl_relaxed(phy, DCSR);
 485         return dcsr & PXA_DCSR_RUN;
 486 }
 487
 488 static bool is_running_chan_misaligned(struct pxad_chan *chan)
 489 {
 490         u32 dalgn;
 491
 492         BUG_ON(!chan->phy);
 493         dalgn = phy_readl_relaxed(chan->phy, DALGN);
 494         return dalgn & (BIT(chan->phy->idx));
 495 }
 496
 497 static void phy_enable(struct pxad_phy *phy, bool misaligned)
 498 {
 499         struct pxad_device *pdev;
 500         u32 reg, dalgn;
 501
 502         if (!phy->vchan)
 503                 return;
 504
 505         dev_dbg(&phy->vchan->vc.chan.dev->device,
 506                 "%s(); phy=%p(%d) misaligned=%d\n", __func__,
 507                 phy, phy->idx, misaligned);
 508
 509         pdev = to_pxad_dev(phy->vchan->vc.chan.device);
 510         if (phy->vchan->drcmr <= pdev->nr_requestors) {
 511                 reg = pxad_drcmr(phy->vchan->drcmr);
 512                 writel_relaxed(DRCMR_MAPVLD | phy->idx, phy->base + reg);
 513         }
 514
 515         dalgn = phy_readl_relaxed(phy, DALGN);
 516         if (misaligned)
 517                 dalgn |= BIT(phy->idx);
 518         else
 519                 dalgn &= ~BIT(phy->idx);
 520         phy_writel_relaxed(phy, dalgn, DALGN);
 521
 522         phy_writel(phy, PXA_DCSR_STOPIRQEN | PXA_DCSR_ENDINTR |
 523                    PXA_DCSR_BUSERR | PXA_DCSR_RUN, DCSR);
 524 }
 525
 526 static void phy_disable(struct pxad_phy *phy)
 527 {
 528         u32 dcsr;
 529
 530         if (!phy)
 531                 return;
 532
 533         dcsr = phy_readl_relaxed(phy, DCSR);
 534         dev_dbg(&phy->vchan->vc.chan.dev->device,
 535                 "%s(): phy=%p(%d)\n", __func__, phy, phy->idx);
 536         phy_writel(phy, dcsr & ~PXA_DCSR_RUN & ~PXA_DCSR_STOPIRQEN, DCSR);
 537 }
 538
 539 static void pxad_launch_chan(struct pxad_chan *chan,
 540                                  struct pxad_desc_sw *desc)
 541 {
 542         dev_dbg(&chan->vc.chan.dev->device,
 543                 "%s(): desc=%p\n", __func__, desc);
 544         if (!chan->phy) {
 545                 chan->phy = lookup_phy(chan);
 546                 if (!chan->phy) {
 547                         dev_dbg(&chan->vc.chan.dev->device,
 548                                 "%s(): no free dma channel\n", __func__);
 549                         return;
 550                 }
 551         }
 552         chan->bus_error = 0;
 553
 554         /*
 555          * Program the descriptor's address into the DMA controller,
 556          * then start the DMA transaction
 557          */
 558         phy_writel(chan->phy, desc->first, DDADR);
 559         phy_enable(chan->phy, chan->misaligned);
 560         wake_up(&chan->wq_state);
 561 }
 562
 563 static void set_updater_desc(struct pxad_desc_sw *sw_desc,
 564                              unsigned long flags)
 565 {
 566         struct pxad_desc_hw *updater =
 567                 sw_desc->hw_desc[sw_desc->nb_desc - 1];
 568         dma_addr_t dma = sw_desc->hw_desc[sw_desc->nb_desc - 2]->ddadr;
 569
 570         updater->ddadr = DDADR_STOP;
 571         updater->dsadr = dma;
 572         updater->dtadr = dma + 8;
 573         updater->dcmd = PXA_DCMD_WIDTH4 | PXA_DCMD_BURST32 |
 574                 (PXA_DCMD_LENGTH & sizeof(u32));
 575         if (flags & DMA_PREP_INTERRUPT)
 576                 updater->dcmd |= PXA_DCMD_ENDIRQEN;
 577         if (sw_desc->cyclic)
 578                 sw_desc->hw_desc[sw_desc->nb_desc - 2]->ddadr = sw_desc->first;
 579 }
 580
 581 static bool is_desc_completed(struct virt_dma_desc *vd)
 582 {
 583         struct pxad_desc_sw *sw_desc = to_pxad_sw_desc(vd);
 584         struct pxad_desc_hw *updater =
 585                 sw_desc->hw_desc[sw_desc->nb_desc - 1];
 586
 587         return updater->dtadr != (updater->dsadr + 8);
 588 }
 589
 590 static void pxad_desc_chain(struct virt_dma_desc *vd1,
 591                                 struct virt_dma_desc *vd2)
 592 {
 593         struct pxad_desc_sw *desc1 = to_pxad_sw_desc(vd1);
 594         struct pxad_desc_sw *desc2 = to_pxad_sw_desc(vd2);
 595         dma_addr_t dma_to_chain;
 596
 597         dma_to_chain = desc2->first;
 598         desc1->hw_desc[desc1->nb_desc - 1]->ddadr = dma_to_chain;
 599 }
 600
 601 static bool pxad_try_hotchain(struct virt_dma_chan *vc,
 602                                   struct virt_dma_desc *vd)
 603 {
 604         struct virt_dma_desc *vd_last_issued = NULL;
 605         struct pxad_chan *chan = to_pxad_chan(&vc->chan);
 606
 607         /*
 608          * Attempt to hot chain the tx if the phy is still running. This is
 609          * considered successful only if either the channel is still running
 610          * after the chaining, or if the chained transfer is completed after
 611          * having been hot chained.
 612          * A change of alignment is not allowed, and forbids hotchaining.
 613          */
 614         if (is_chan_running(chan)) {
 615                 BUG_ON(list_empty(&vc->desc_issued));
 616
 617                 if (!is_running_chan_misaligned(chan) &&
 618                     to_pxad_sw_desc(vd)->misaligned)
 619                         return false;
 620
 621                 vd_last_issued = list_entry(vc->desc_issued.prev,
 622                                             struct virt_dma_desc, node);
 623                 pxad_desc_chain(vd_last_issued, vd);
 624                 if (is_chan_running(chan) || is_desc_completed(vd))
 625                         return true;
 626         }
 627
 628         return false;
 629 }
 630
 631 static unsigned int clear_chan_irq(struct pxad_phy *phy)
 632 {
 633         u32 dcsr;
 634         u32 dint = readl(phy->base + DINT);
 635
 636         if (!(dint & BIT(phy->idx)))
 637                 return PXA_DCSR_RUN;
 638
 639         /* clear irq */
 640         dcsr = phy_readl_relaxed(phy, DCSR);
 641         phy_writel(phy, dcsr, DCSR);
 642         if ((dcsr & PXA_DCSR_BUSERR) && (phy->vchan))
 643                 dev_warn(&phy->vchan->vc.chan.dev->device,
 644                          "%s(chan=%p): PXA_DCSR_BUSERR\n",
 645                          __func__, &phy->vchan);
 646
 647         return dcsr & ~PXA_DCSR_RUN;
 648 }
 649
 650 static irqreturn_t pxad_chan_handler(int irq, void *dev_id)
 651 {
 652         struct pxad_phy *phy = dev_id;
 653         struct pxad_chan *chan = phy->vchan;
 654         struct virt_dma_desc *vd, *tmp;
 655         unsigned int dcsr;
 656         unsigned long flags;
 657         bool vd_completed;
 658         dma_cookie_t last_started = 0;
 659
 660         BUG_ON(!chan);
 661
 662         dcsr = clear_chan_irq(phy);
 663         if (dcsr & PXA_DCSR_RUN)
 664                 return IRQ_NONE;
 665
 666         spin_lock_irqsave(&chan->vc.lock, flags);
 667         list_for_each_entry_safe(vd, tmp, &chan->vc.desc_issued, node) {
 668                 vd_completed = is_desc_completed(vd);
 669                 dev_dbg(&chan->vc.chan.dev->device,
 670                         "%s(): checking txd %p[%x]: completed=%d dcsr=0x%x\n",
 671                         __func__, vd, vd->tx.cookie, vd_completed,
 672                         dcsr);
 673                 last_started = vd->tx.cookie;
 674                 if (to_pxad_sw_desc(vd)->cyclic) {
 675                         vchan_cyclic_callback(vd);
 676                         break;
 677                 }
 678                 if (vd_completed) {
 679                         list_del(&vd->node);
 680                         vchan_cookie_complete(vd);
 681                 } else {
 682                         break;
 683                 }
 684         }
 685
 686         if (dcsr & PXA_DCSR_BUSERR) {
 687                 chan->bus_error = last_started;
 688                 phy_disable(phy);
 689         }
 690
 691         if (!chan->bus_error && dcsr & PXA_DCSR_STOPSTATE) {
 692                 dev_dbg(&chan->vc.chan.dev->device,
 693                 "%s(): channel stopped, submitted_empty=%d issued_empty=%d",
 694                         __func__,
 695                         list_empty(&chan->vc.desc_submitted),
 696                         list_empty(&chan->vc.desc_issued));
 697                 phy_writel_relaxed(phy, dcsr & ~PXA_DCSR_STOPIRQEN, DCSR);
 698
 699                 if (list_empty(&chan->vc.desc_issued)) {
 700                         chan->misaligned =
 701                                 !list_empty(&chan->vc.desc_submitted);
 702                 } else {
 703                         vd = list_first_entry(&chan->vc.desc_issued,
 704                                               struct virt_dma_desc, node);
 705                         pxad_launch_chan(chan, to_pxad_sw_desc(vd));
 706                 }
 707         }
 708         spin_unlock_irqrestore(&chan->vc.lock, flags);
 709         wake_up(&chan->wq_state);
 710
 711         return IRQ_HANDLED;
 712 }
 713
 714 static irqreturn_t pxad_int_handler(int irq, void *dev_id)
 715 {
 716         struct pxad_device *pdev = dev_id;
 717         struct pxad_phy *phy;
 718         u32 dint = readl(pdev->base + DINT);
 719         int i, ret = IRQ_NONE;
 720
 721         while (dint) {
 722                 i = __ffs(dint);
 723                 dint &= (dint - 1);
 724                 phy = &pdev->phys[i];
 725                 if (pxad_chan_handler(irq, phy) == IRQ_HANDLED)
 726                         ret = IRQ_HANDLED;
 727         }
 728
 729         return ret;
 730 }
 731
 732 static int pxad_alloc_chan_resources(struct dma_chan *dchan)
 733 {
 734         struct pxad_chan *chan = to_pxad_chan(dchan);
 735         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
 736
 737         if (chan->desc_pool)
 738                 return 1;
 739
 740         chan->desc_pool = dma_pool_create(dma_chan_name(dchan),
 741                                           pdev->slave.dev,
 742                                           sizeof(struct pxad_desc_hw),
 743                                           __alignof__(struct pxad_desc_hw),
 744                                           0);
 745         if (!chan->desc_pool) {
 746                 dev_err(&chan->vc.chan.dev->device,
 747                         "%s(): unable to allocate descriptor pool\n",
 748                         __func__);
 749                 return -ENOMEM;
 750         }
 751
 752         return 1;
 753 }
 754
 755 static void pxad_free_chan_resources(struct dma_chan *dchan)
 756 {
 757         struct pxad_chan *chan = to_pxad_chan(dchan);
 758
 759         vchan_free_chan_resources(&chan->vc);
 760         dma_pool_destroy(chan->desc_pool);
 761         chan->desc_pool = NULL;
 762
 763 }
 764
 765 static void pxad_free_desc(struct virt_dma_desc *vd)
 766 {
 767         int i;
 768         dma_addr_t dma;
 769         struct pxad_desc_sw *sw_desc = to_pxad_sw_desc(vd);
 770
 771         BUG_ON(sw_desc->nb_desc == 0);
 772         for (i = sw_desc->nb_desc - 1; i >= 0; i--) {
 773                 if (i > 0)
 774                         dma = sw_desc->hw_desc[i - 1]->ddadr;
 775                 else
 776                         dma = sw_desc->first;
 777                 dma_pool_free(sw_desc->desc_pool,
 778                               sw_desc->hw_desc[i], dma);
 779         }
 780         sw_desc->nb_desc = 0;
 781         kfree(sw_desc);
 782 }
 783
 784 static struct pxad_desc_sw *
 785 pxad_alloc_desc(struct pxad_chan *chan, unsigned int nb_hw_desc)
 786 {
 787         struct pxad_desc_sw *sw_desc;
 788         dma_addr_t dma;
 789         int i;
 790
 791         sw_desc = kzalloc(sizeof(*sw_desc) +
 792                           nb_hw_desc * sizeof(struct pxad_desc_hw *),
 793                           GFP_NOWAIT);
 794         if (!sw_desc)
 795                 return NULL;
 796         sw_desc->desc_pool = chan->desc_pool;
 797
 798         for (i = 0; i < nb_hw_desc; i++) {
 799                 sw_desc->hw_desc[i] = dma_pool_alloc(sw_desc->desc_pool,
 800                                                      GFP_NOWAIT, &dma);
 801                 if (!sw_desc->hw_desc[i]) {
 802                         dev_err(&chan->vc.chan.dev->device,
 803                                 "%s(): Couldn't allocate the %dth hw_desc from dma_pool %p\n",
 804                                 __func__, i, sw_desc->desc_pool);
 805                         goto err;
 806                 }
 807
 808                 if (i == 0)
 809                         sw_desc->first = dma;
 810                 else
 811                         sw_desc->hw_desc[i - 1]->ddadr = dma;
 812                 sw_desc->nb_desc++;
 813         }
 814
 815         return sw_desc;
 816 err:
 817         pxad_free_desc(&sw_desc->vd);
 818         return NULL;
 819 }
 820
 821 static dma_cookie_t pxad_tx_submit(struct dma_async_tx_descriptor *tx)
 822 {
 823         struct virt_dma_chan *vc = to_virt_chan(tx->chan);
 824         struct pxad_chan *chan = to_pxad_chan(&vc->chan);
 825         struct virt_dma_desc *vd_chained = NULL,
 826                 *vd = container_of(tx, struct virt_dma_desc, tx);
 827         dma_cookie_t cookie;
 828         unsigned long flags;
 829
 830         set_updater_desc(to_pxad_sw_desc(vd), tx->flags);
 831
 832         spin_lock_irqsave(&vc->lock, flags);
 833         cookie = dma_cookie_assign(tx);
 834
 835         if (list_empty(&vc->desc_submitted) && pxad_try_hotchain(vc, vd)) {
 836                 list_move_tail(&vd->node, &vc->desc_issued);
 837                 dev_dbg(&chan->vc.chan.dev->device,
 838                         "%s(): txd %p[%x]: submitted (hot linked)\n",
 839                         __func__, vd, cookie);
 840                 goto out;
 841         }
 842
 843         /*
 844          * Fallback to placing the tx in the submitted queue
 845          */
 846         if (!list_empty(&vc->desc_submitted)) {
 847                 vd_chained = list_entry(vc->desc_submitted.prev,
 848                                         struct virt_dma_desc, node);
 849                 /*
 850                  * Only chain the descriptors if no new misalignment is
 851                  * introduced. If a new misalignment is chained, let the channel
 852                  * stop, and be relaunched in misalign mode from the irq
 853                  * handler.
 854                  */
 855                 if (chan->misaligned || !to_pxad_sw_desc(vd)->misaligned)
 856                         pxad_desc_chain(vd_chained, vd);
 857                 else
 858                         vd_chained = NULL;
 859         }
 860         dev_dbg(&chan->vc.chan.dev->device,
 861                 "%s(): txd %p[%x]: submitted (%s linked)\n",
 862                 __func__, vd, cookie, vd_chained ? "cold" : "not");
 863         list_move_tail(&vd->node, &vc->desc_submitted);
 864         chan->misaligned |= to_pxad_sw_desc(vd)->misaligned;
 865
 866 out:
 867         spin_unlock_irqrestore(&vc->lock, flags);
 868         return cookie;
 869 }
 870
 871 static void pxad_issue_pending(struct dma_chan *dchan)
 872 {
 873         struct pxad_chan *chan = to_pxad_chan(dchan);
 874         struct virt_dma_desc *vd_first;
 875         unsigned long flags;
 876
 877         spin_lock_irqsave(&chan->vc.lock, flags);
 878         if (list_empty(&chan->vc.desc_submitted))
 879                 goto out;
 880
 881         vd_first = list_first_entry(&chan->vc.desc_submitted,
 882                                     struct virt_dma_desc, node);
 883         dev_dbg(&chan->vc.chan.dev->device,
 884                 "%s(): txd %p[%x]", __func__, vd_first, vd_first->tx.cookie);
 885
 886         vchan_issue_pending(&chan->vc);
 887         if (!pxad_try_hotchain(&chan->vc, vd_first))
 888                 pxad_launch_chan(chan, to_pxad_sw_desc(vd_first));
 889 out:
 890         spin_unlock_irqrestore(&chan->vc.lock, flags);
 891 }
 892
 893 static inline struct dma_async_tx_descriptor *
 894 pxad_tx_prep(struct virt_dma_chan *vc, struct virt_dma_desc *vd,
 895                  unsigned long tx_flags)
 896 {
 897         struct dma_async_tx_descriptor *tx;
 898         struct pxad_chan *chan = container_of(vc, struct pxad_chan, vc);
 899
 900         INIT_LIST_HEAD(&vd->node);
 901         tx = vchan_tx_prep(vc, vd, tx_flags);
 902         tx->tx_submit = pxad_tx_submit;
 903         dev_dbg(&chan->vc.chan.dev->device,
 904                 "%s(): vc=%p txd=%p[%x] flags=0x%lx\n", __func__,
 905                 vc, vd, vd->tx.cookie,
 906                 tx_flags);
 907
 908         return tx;
 909 }
 910
 911 static void pxad_get_config(struct pxad_chan *chan,
 912                             enum dma_transfer_direction dir,
 913                             u32 *dcmd, u32 *dev_src, u32 *dev_dst)
 914 {
 915         u32 maxburst = 0, dev_addr = 0;
 916         enum dma_slave_buswidth width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
 917         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
 918
 919         *dcmd = 0;
 920         if (dir == DMA_DEV_TO_MEM) {
 921                 maxburst = chan->cfg.src_maxburst;
 922                 width = chan->cfg.src_addr_width;
 923                 dev_addr = chan->cfg.src_addr;
 924                 *dev_src = dev_addr;
 925                 *dcmd |= PXA_DCMD_INCTRGADDR;
 926                 if (chan->drcmr <= pdev->nr_requestors)
 927                         *dcmd |= PXA_DCMD_FLOWSRC;
 928         }
 929         if (dir == DMA_MEM_TO_DEV) {
 930                 maxburst = chan->cfg.dst_maxburst;
 931                 width = chan->cfg.dst_addr_width;
 932                 dev_addr = chan->cfg.dst_addr;
 933                 *dev_dst = dev_addr;
 934                 *dcmd |= PXA_DCMD_INCSRCADDR;
 935                 if (chan->drcmr <= pdev->nr_requestors)
 936                         *dcmd |= PXA_DCMD_FLOWTRG;
 937         }
 938         if (dir == DMA_MEM_TO_MEM)
 939                 *dcmd |= PXA_DCMD_BURST32 | PXA_DCMD_INCTRGADDR |
 940                         PXA_DCMD_INCSRCADDR;
 941
 942         dev_dbg(&chan->vc.chan.dev->device,
 943                 "%s(): dev_addr=0x%x maxburst=%d width=%d  dir=%d\n",
 944                 __func__, dev_addr, maxburst, width, dir);
 945
 946         if (width == DMA_SLAVE_BUSWIDTH_1_BYTE)
 947                 *dcmd |= PXA_DCMD_WIDTH1;
 948         else if (width == DMA_SLAVE_BUSWIDTH_2_BYTES)
 949                 *dcmd |= PXA_DCMD_WIDTH2;
 950         else if (width == DMA_SLAVE_BUSWIDTH_4_BYTES)
 951                 *dcmd |= PXA_DCMD_WIDTH4;
 952
 953         if (maxburst == 8)
 954                 *dcmd |= PXA_DCMD_BURST8;
 955         else if (maxburst == 16)
 956                 *dcmd |= PXA_DCMD_BURST16;
 957         else if (maxburst == 32)
 958                 *dcmd |= PXA_DCMD_BURST32;
 959
 960         /* FIXME: drivers should be ported over to use the filter
 961          * function. Once that's done, the following two lines can
 962          * be removed.
 963          */
 964         if (chan->cfg.slave_id)
 965                 chan->drcmr = chan->cfg.slave_id;
 966 }
 967
 968 static struct dma_async_tx_descriptor *
 969 pxad_prep_memcpy(struct dma_chan *dchan,
 970                  dma_addr_t dma_dst, dma_addr_t dma_src,
 971                  size_t len, unsigned long flags)
 972 {
 973         struct pxad_chan *chan = to_pxad_chan(dchan);
 974         struct pxad_desc_sw *sw_desc;
 975         struct pxad_desc_hw *hw_desc;
 976         u32 dcmd;
 977         unsigned int i, nb_desc = 0;
 978         size_t copy;
 979
 980         if (!dchan || !len)
 981                 return NULL;
 982
 983         dev_dbg(&chan->vc.chan.dev->device,
 984                 "%s(): dma_dst=0x%lx dma_src=0x%lx len=%zu flags=%lx\n",
 985                 __func__, (unsigned long)dma_dst, (unsigned long)dma_src,
 986                 len, flags);
 987         pxad_get_config(chan, DMA_MEM_TO_MEM, &dcmd, NULL, NULL);
 988
 989         nb_desc = DIV_ROUND_UP(len, PDMA_MAX_DESC_BYTES);
 990         sw_desc = pxad_alloc_desc(chan, nb_desc + 1);
 991         if (!sw_desc)
 992                 return NULL;
 993         sw_desc->len = len;
 994
 995         if (!IS_ALIGNED(dma_src, 1 << PDMA_ALIGNMENT) ||
 996             !IS_ALIGNED(dma_dst, 1 << PDMA_ALIGNMENT))
 997                 sw_desc->misaligned = true;
 998
 999         i = 0;
1000         do {
1001                 hw_desc = sw_desc->hw_desc[i++];
1002                 copy = min_t(size_t, len, PDMA_MAX_DESC_BYTES);
1003                 hw_desc->dcmd = dcmd | (PXA_DCMD_LENGTH & copy);
1004                 hw_desc->dsadr = dma_src;
1005                 hw_desc->dtadr = dma_dst;
1006                 len -= copy;
1007                 dma_src += copy;
1008                 dma_dst += copy;
1009         } while (len);
1010         set_updater_desc(sw_desc, flags);
1011
1012         return pxad_tx_prep(&chan->vc, &sw_desc->vd, flags);
1013 }
1014
1015 static struct dma_async_tx_descriptor *
1016 pxad_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
1017                    unsigned int sg_len, enum dma_transfer_direction dir,
1018                    unsigned long flags, void *context)
1019 {
1020         struct pxad_chan *chan = to_pxad_chan(dchan);
1021         struct pxad_desc_sw *sw_desc;
1022         size_t len, avail;
1023         struct scatterlist *sg;
1024         dma_addr_t dma;
1025         u32 dcmd, dsadr = 0, dtadr = 0;
1026         unsigned int nb_desc = 0, i, j = 0;
1027
1028         if ((sgl == NULL) || (sg_len == 0))
1029                 return NULL;
1030
1031         pxad_get_config(chan, dir, &dcmd, &dsadr, &dtadr);
1032         dev_dbg(&chan->vc.chan.dev->device,
1033                 "%s(): dir=%d flags=%lx\n", __func__, dir, flags);
1034
1035         for_each_sg(sgl, sg, sg_len, i)
1036                 nb_desc += DIV_ROUND_UP(sg_dma_len(sg), PDMA_MAX_DESC_BYTES);
1037         sw_desc = pxad_alloc_desc(chan, nb_desc + 1);
1038         if (!sw_desc)
1039                 return NULL;
1040
1041         for_each_sg(sgl, sg, sg_len, i) {
1042                 dma = sg_dma_address(sg);
1043                 avail = sg_dma_len(sg);
1044                 sw_desc->len += avail;
1045
1046                 do {
1047                         len = min_t(size_t, avail, PDMA_MAX_DESC_BYTES);
1048                         if (dma & 0x7)
1049                                 sw_desc->misaligned = true;
1050
1051                         sw_desc->hw_desc[j]->dcmd =
1052                                 dcmd | (PXA_DCMD_LENGTH & len);
1053                         sw_desc->hw_desc[j]->dsadr = dsadr ? dsadr : dma;
1054                         sw_desc->hw_desc[j++]->dtadr = dtadr ? dtadr : dma;
1055
1056                         dma += len;
1057                         avail -= len;
1058                 } while (avail);
1059         }
1060         set_updater_desc(sw_desc, flags);
1061
1062         return pxad_tx_prep(&chan->vc, &sw_desc->vd, flags);
1063 }
1064
1065 static struct dma_async_tx_descriptor *
1066 pxad_prep_dma_cyclic(struct dma_chan *dchan,
1067                      dma_addr_t buf_addr, size_t len, size_t period_len,
1068                      enum dma_transfer_direction dir, unsigned long flags)
1069 {
1070         struct pxad_chan *chan = to_pxad_chan(dchan);
1071         struct pxad_desc_sw *sw_desc;
1072         struct pxad_desc_hw **phw_desc;
1073         dma_addr_t dma;
1074         u32 dcmd, dsadr = 0, dtadr = 0;
1075         unsigned int nb_desc = 0;
1076
1077         if (!dchan || !len || !period_len)
1078                 return NULL;
1079         if ((dir != DMA_DEV_TO_MEM) && (dir != DMA_MEM_TO_DEV)) {
1080                 dev_err(&chan->vc.chan.dev->device,
1081                         "Unsupported direction for cyclic DMA\n");
1082                 return NULL;
1083         }
1084         /* the buffer length must be a multiple of period_len */
1085         if (len % period_len != 0 || period_len > PDMA_MAX_DESC_BYTES ||
1086             !IS_ALIGNED(period_len, 1 << PDMA_ALIGNMENT))
1087                 return NULL;
1088
1089         pxad_get_config(chan, dir, &dcmd, &dsadr, &dtadr);
1090         dcmd |= PXA_DCMD_ENDIRQEN | (PXA_DCMD_LENGTH & period_len);
1091         dev_dbg(&chan->vc.chan.dev->device,
1092                 "%s(): buf_addr=0x%lx len=%zu period=%zu dir=%d flags=%lx\n",
1093                 __func__, (unsigned long)buf_addr, len, period_len, dir, flags);
1094
1095         nb_desc = DIV_ROUND_UP(period_len, PDMA_MAX_DESC_BYTES);
1096         nb_desc *= DIV_ROUND_UP(len, period_len);
1097         sw_desc = pxad_alloc_desc(chan, nb_desc + 1);
1098         if (!sw_desc)
1099                 return NULL;
1100         sw_desc->cyclic = true;
1101         sw_desc->len = len;
1102
1103         phw_desc = sw_desc->hw_desc;
1104         dma = buf_addr;
1105         do {
1106                 phw_desc[0]->dsadr = dsadr ? dsadr : dma;
1107                 phw_desc[0]->dtadr = dtadr ? dtadr : dma;
1108                 phw_desc[0]->dcmd = dcmd;
1109                 phw_desc++;
1110                 dma += period_len;
1111                 len -= period_len;
1112         } while (len);
1113         set_updater_desc(sw_desc, flags);
1114
1115         return pxad_tx_prep(&chan->vc, &sw_desc->vd, flags);
1116 }
1117
1118 static int pxad_config(struct dma_chan *dchan,
1119                        struct dma_slave_config *cfg)
1120 {
1121         struct pxad_chan *chan = to_pxad_chan(dchan);
1122
1123         if (!dchan)
1124                 return -EINVAL;
1125
1126         chan->cfg = *cfg;
1127         return 0;
1128 }
1129
1130 static int pxad_terminate_all(struct dma_chan *dchan)
1131 {
1132         struct pxad_chan *chan = to_pxad_chan(dchan);
1133         struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
1134         struct virt_dma_desc *vd = NULL;
1135         unsigned long flags;
1136         struct pxad_phy *phy;
1137         LIST_HEAD(head);
1138
1139         dev_dbg(&chan->vc.chan.dev->device,
1140                 "%s(): vchan %p: terminate all\n", __func__, &chan->vc);
1141
1142         spin_lock_irqsave(&chan->vc.lock, flags);
1143         vchan_get_all_descriptors(&chan->vc, &head);
1144
1145         list_for_each_entry(vd, &head, node) {
1146                 dev_dbg(&chan->vc.chan.dev->device,
1147                         "%s(): cancelling txd %p[%x] (completed=%d)", __func__,
1148                         vd, vd->tx.cookie, is_desc_completed(vd));
1149         }
1150
1151         phy = chan->phy;
1152         if (phy) {
1153                 phy_disable(chan->phy);
1154                 pxad_free_phy(chan);
1155                 chan->phy = NULL;
1156                 spin_lock(&pdev->phy_lock);
1157                 phy->vchan = NULL;
1158                 spin_unlock(&pdev->phy_lock);
1159         }
1160         spin_unlock_irqrestore(&chan->vc.lock, flags);
1161         vchan_dma_desc_free_list(&chan->vc, &head);
1162
1163         return 0;
1164 }
1165
1166 static unsigned int pxad_residue(struct pxad_chan *chan,
1167                                  dma_cookie_t cookie)
1168 {
1169         struct virt_dma_desc *vd = NULL;
1170         struct pxad_desc_sw *sw_desc = NULL;
1171         struct pxad_desc_hw *hw_desc = NULL;
1172         u32 curr, start, len, end, residue = 0;
1173         unsigned long flags;
1174         bool passed = false;
1175         int i;
1176
1177         /*
1178          * If the channel does not have a phy pointer anymore, it has already
1179          * been completed. Therefore, its residue is 0.
1180          */
1181         if (!chan->phy)
1182                 return 0;
1183
1184         spin_lock_irqsave(&chan->vc.lock, flags);
1185
1186         vd = vchan_find_desc(&chan->vc, cookie);
1187         if (!vd)
1188                 goto out;
1189
1190         sw_desc = to_pxad_sw_desc(vd);
1191         if (sw_desc->hw_desc[0]->dcmd & PXA_DCMD_INCSRCADDR)
1192                 curr = phy_readl_relaxed(chan->phy, DSADR);
1193         else
1194                 curr = phy_readl_relaxed(chan->phy, DTADR);
1195
1196         /*
1197          * curr has to be actually read before checking descriptor
1198          * completion, so that a curr inside a status updater
1199          * descriptor implies the following test returns true, and
1200          * preventing reordering of curr load and the test.
1201          */
1202         rmb();
1203         if (is_desc_completed(vd))
1204                 goto out;
1205
1206         for (i = 0; i < sw_desc->nb_desc - 1; i++) {
1207                 hw_desc = sw_desc->hw_desc[i];
1208                 if (sw_desc->hw_desc[0]->dcmd & PXA_DCMD_INCSRCADDR)
1209                         start = hw_desc->dsadr;
1210                 else
1211                         start = hw_desc->dtadr;
1212                 len = hw_desc->dcmd & PXA_DCMD_LENGTH;
1213                 end = start + len;
1214
1215                 /*
1216                  * 'passed' will be latched once we found the descriptor
1217                  * which lies inside the boundaries of the curr
1218                  * pointer. All descriptors that occur in the list
1219                  * _after_ we found that partially handled descriptor
1220                  * are still to be processed and are hence added to the
1221                  * residual bytes counter.
1222                  */
1223
1224                 if (passed) {
1225                         residue += len;
1226                 } else if (curr >= start && curr <= end) {
1227                         residue += end - curr;
1228                         passed = true;
1229                 }
1230         }
1231         if (!passed)
1232                 residue = sw_desc->len;
1233
1234 out:
1235         spin_unlock_irqrestore(&chan->vc.lock, flags);
1236         dev_dbg(&chan->vc.chan.dev->device,
1237                 "%s(): txd %p[%x] sw_desc=%p: %d\n",
1238                 __func__, vd, cookie, sw_desc, residue);
1239         return residue;
1240 }
1241
1242 static enum dma_status pxad_tx_status(struct dma_chan *dchan,
1243                                       dma_cookie_t cookie,
1244                                       struct dma_tx_state *txstate)
1245 {
1246         struct pxad_chan *chan = to_pxad_chan(dchan);
1247         enum dma_status ret;
1248
1249         if (cookie == chan->bus_error)
1250                 return DMA_ERROR;
1251
1252         ret = dma_cookie_status(dchan, cookie, txstate);
1253         if (likely(txstate && (ret != DMA_ERROR)))
1254                 dma_set_residue(txstate, pxad_residue(chan, cookie));
1255
1256         return ret;
1257 }
1258
1259 static void pxad_synchronize(struct dma_chan *dchan)
1260 {
1261         struct pxad_chan *chan = to_pxad_chan(dchan);
1262
1263         wait_event(chan->wq_state, !is_chan_running(chan));
1264         vchan_synchronize(&chan->vc);
1265 }
1266
1267 static void pxad_free_channels(struct dma_device *dmadev)
1268 {
1269         struct pxad_chan *c, *cn;
1270
1271         list_for_each_entry_safe(c, cn, &dmadev->channels,
1272                                  vc.chan.device_node) {
1273                 list_del(&c->vc.chan.device_node);
1274                 tasklet_kill(&c->vc.task);
1275         }
1276 }
1277
1278 static int pxad_remove(struct platform_device *op)
1279 {
1280         struct pxad_device *pdev = platform_get_drvdata(op);
1281
1282         pxad_cleanup_debugfs(pdev);
1283         pxad_free_channels(&pdev->slave);
1284         dma_async_device_unregister(&pdev->slave);
1285         return 0;
1286 }
1287
1288 static int pxad_init_phys(struct platform_device *op,
1289                           struct pxad_device *pdev,
1290                           unsigned int nb_phy_chans)
1291 {
1292         int irq0, irq, nr_irq = 0, i, ret;
1293         struct pxad_phy *phy;
1294
1295         irq0 = platform_get_irq(op, 0);
1296         if (irq0 < 0)
1297                 return irq0;
1298
1299         pdev->phys = devm_kcalloc(&op->dev, nb_phy_chans,
1300                                   sizeof(pdev->phys[0]), GFP_KERNEL);
1301         if (!pdev->phys)
1302                 return -ENOMEM;
1303
1304         for (i = 0; i < nb_phy_chans; i++)
1305                 if (platform_get_irq(op, i) > 0)
1306                         nr_irq++;
1307
1308         for (i = 0; i < nb_phy_chans; i++) {
1309                 phy = &pdev->phys[i];
1310                 phy->base = pdev->base;
1311                 phy->idx = i;
1312                 irq = platform_get_irq(op, i);
1313                 if ((nr_irq > 1) && (irq > 0))
1314                         ret = devm_request_irq(&op->dev, irq,
1315                                                pxad_chan_handler,
1316                                                IRQF_SHARED, "pxa-dma", phy);
1317                 if ((nr_irq == 1) && (i == 0))
1318                         ret = devm_request_irq(&op->dev, irq0,
1319                                                pxad_int_handler,
1320                                                IRQF_SHARED, "pxa-dma", pdev);
1321                 if (ret) {
1322                         dev_err(pdev->slave.dev,
1323                                 "%s(): can't request irq %d:%d\n", __func__,
1324                                 irq, ret);
1325                         return ret;
1326                 }
1327         }
1328
1329         return 0;
1330 }
1331
1332 static const struct of_device_id pxad_dt_ids[] = {
1333         { .compatible = "marvell,pdma-1.0", },
1334         {}
1335 };
1336 MODULE_DEVICE_TABLE(of, pxad_dt_ids);
1337
1338 static struct dma_chan *pxad_dma_xlate(struct of_phandle_args *dma_spec,
1339                                            struct of_dma *ofdma)
1340 {
1341         struct pxad_device *d = ofdma->of_dma_data;
1342         struct dma_chan *chan;
1343
1344         chan = dma_get_any_slave_channel(&d->slave);
1345         if (!chan)
1346                 return NULL;
1347
1348         to_pxad_chan(chan)->drcmr = dma_spec->args[0];
1349         to_pxad_chan(chan)->prio = dma_spec->args[1];
1350
1351         return chan;
1352 }
1353
1354 static int pxad_init_dmadev(struct platform_device *op,
1355                             struct pxad_device *pdev,
1356                             unsigned int nr_phy_chans,
1357                             unsigned int nr_requestors)
1358 {
1359         int ret;
1360         unsigned int i;
1361         struct pxad_chan *c;
1362
1363         pdev->nr_chans = nr_phy_chans;
1364         pdev->nr_requestors = nr_requestors;
1365         INIT_LIST_HEAD(&pdev->slave.channels);
1366         pdev->slave.device_alloc_chan_resources = pxad_alloc_chan_resources;
1367         pdev->slave.device_free_chan_resources = pxad_free_chan_resources;
1368         pdev->slave.device_tx_status = pxad_tx_status;
1369         pdev->slave.device_issue_pending = pxad_issue_pending;
1370         pdev->slave.device_config = pxad_config;
1371         pdev->slave.device_synchronize = pxad_synchronize;
1372         pdev->slave.device_terminate_all = pxad_terminate_all;
1373
1374         if (op->dev.coherent_dma_mask)
1375                 dma_set_mask(&op->dev, op->dev.coherent_dma_mask);
1376         else
1377                 dma_set_mask(&op->dev, DMA_BIT_MASK(32));
1378
1379         ret = pxad_init_phys(op, pdev, nr_phy_chans);
1380         if (ret)
1381                 return ret;
1382
1383         for (i = 0; i < nr_phy_chans; i++) {
1384                 c = devm_kzalloc(&op->dev, sizeof(*c), GFP_KERNEL);
1385                 if (!c)
1386                         return -ENOMEM;
1387                 c->vc.desc_free = pxad_free_desc;
1388                 vchan_init(&c->vc, &pdev->slave);
1389                 init_waitqueue_head(&c->wq_state);
1390         }
1391
1392         return dma_async_device_register(&pdev->slave);
1393 }
1394
1395 static int pxad_probe(struct platform_device *op)
1396 {
1397         struct pxad_device *pdev;
1398         const struct of_device_id *of_id;
1399         struct mmp_dma_platdata *pdata = dev_get_platdata(&op->dev);
1400         struct resource *iores;
1401         int ret, dma_channels = 0, nb_requestors = 0;
1402         const enum dma_slave_buswidth widths =
1403                 DMA_SLAVE_BUSWIDTH_1_BYTE   | DMA_SLAVE_BUSWIDTH_2_BYTES |
1404                 DMA_SLAVE_BUSWIDTH_4_BYTES;
1405
1406         pdev = devm_kzalloc(&op->dev, sizeof(*pdev), GFP_KERNEL);
1407         if (!pdev)
1408                 return -ENOMEM;
1409
1410         spin_lock_init(&pdev->phy_lock);
1411
1412         iores = platform_get_resource(op, IORESOURCE_MEM, 0);
1413         pdev->base = devm_ioremap_resource(&op->dev, iores);
1414         if (IS_ERR(pdev->base))
1415                 return PTR_ERR(pdev->base);
1416
1417         of_id = of_match_device(pxad_dt_ids, &op->dev);
1418         if (of_id) {
1419                 of_property_read_u32(op->dev.of_node, "#dma-channels",
1420                                      &dma_channels);
1421                 ret = of_property_read_u32(op->dev.of_node, "#dma-requests",
1422                                            &nb_requestors);
1423                 if (ret) {
1424                         dev_warn(pdev->slave.dev,
1425                                  "#dma-requests set to default 32 as missing in OF: %d",
1426                                  ret);
1427                         nb_requestors = 32;
1428                 };
1429         } else if (pdata && pdata->dma_channels) {
1430                 dma_channels = pdata->dma_channels;
1431                 nb_requestors = pdata->nb_requestors;
1432         } else {
1433                 dma_channels = 32;      /* default 32 channel */
1434         }
1435
1436         dma_cap_set(DMA_SLAVE, pdev->slave.cap_mask);
1437         dma_cap_set(DMA_MEMCPY, pdev->slave.cap_mask);
1438         dma_cap_set(DMA_CYCLIC, pdev->slave.cap_mask);
1439         dma_cap_set(DMA_PRIVATE, pdev->slave.cap_mask);
1440         pdev->slave.device_prep_dma_memcpy = pxad_prep_memcpy;
1441         pdev->slave.device_prep_slave_sg = pxad_prep_slave_sg;
1442         pdev->slave.device_prep_dma_cyclic = pxad_prep_dma_cyclic;
1443
1444         pdev->slave.copy_align = PDMA_ALIGNMENT;
1445         pdev->slave.src_addr_widths = widths;
1446         pdev->slave.dst_addr_widths = widths;
1447         pdev->slave.directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
1448         pdev->slave.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
1449         pdev->slave.descriptor_reuse = true;
1450
1451         pdev->slave.dev = &op->dev;
1452         ret = pxad_init_dmadev(op, pdev, dma_channels, nb_requestors);
1453         if (ret) {
1454                 dev_err(pdev->slave.dev, "unable to register\n");
1455                 return ret;
1456         }
1457
1458         if (op->dev.of_node) {
1459                 /* Device-tree DMA controller registration */
1460                 ret = of_dma_controller_register(op->dev.of_node,
1461                                                  pxad_dma_xlate, pdev);
1462                 if (ret < 0) {
1463                         dev_err(pdev->slave.dev,
1464                                 "of_dma_controller_register failed\n");
1465                         return ret;
1466                 }
1467         }
1468
1469         platform_set_drvdata(op, pdev);
1470         pxad_init_debugfs(pdev);
1471         dev_info(pdev->slave.dev, "initialized %d channels on %d requestors\n",
1472                  dma_channels, nb_requestors);
1473         return 0;
1474 }
1475
1476 static const struct platform_device_id pxad_id_table[] = {
1477         { "pxa-dma", },
1478         { },
1479 };
1480
1481 static struct platform_driver pxad_driver = {
1482         .driver         = {
1483                 .name   = "pxa-dma",
1484                 .of_match_table = pxad_dt_ids,
1485         },
1486         .id_table       = pxad_id_table,
1487         .probe          = pxad_probe,
1488         .remove         = pxad_remove,
1489 };
1490
1491 bool pxad_filter_fn(struct dma_chan *chan, void *param)
1492 {
1493         struct pxad_chan *c = to_pxad_chan(chan);
1494         struct pxad_param *p = param;
1495
1496         if (chan->device->dev->driver != &pxad_driver.driver)
1497                 return false;
1498
1499         c->drcmr = p->drcmr;
1500         c->prio = p->prio;
1501
1502         return true;
1503 }
1504 EXPORT_SYMBOL_GPL(pxad_filter_fn);
1505
1506 module_platform_driver(pxad_driver);
1507
1508 MODULE_DESCRIPTION("Marvell PXA Peripheral DMA Driver");
1509 MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
1510 MODULE_LICENSE("GPL v2");