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