drivers/dma/ti/cppi41.c

   1 #include <linux/delay.h>
   2 #include <linux/dmaengine.h>
   3 #include <linux/dma-mapping.h>
   4 #include <linux/platform_device.h>
   5 #include <linux/module.h>
   6 #include <linux/of.h>
   7 #include <linux/slab.h>
   8 #include <linux/of_dma.h>
   9 #include <linux/of_irq.h>
  10 #include <linux/dmapool.h>
  11 #include <linux/interrupt.h>
  12 #include <linux/of_address.h>
  13 #include <linux/pm_runtime.h>
  14 #include "../dmaengine.h"
  15
  16 #define DESC_TYPE       27
  17 #define DESC_TYPE_HOST  0x10
  18 #define DESC_TYPE_TEARD 0x13
  19
  20 #define TD_DESC_IS_RX   (1 << 16)
  21 #define TD_DESC_DMA_NUM 10
  22
  23 #define DESC_LENGTH_BITS_NUM    21
  24
  25 #define DESC_TYPE_USB   (5 << 26)
  26 #define DESC_PD_COMPLETE        (1 << 31)
  27
  28 /* DMA engine */
  29 #define DMA_TDFDQ       4
  30 #define DMA_TXGCR(x)    (0x800 + (x) * 0x20)
  31 #define DMA_RXGCR(x)    (0x808 + (x) * 0x20)
  32 #define RXHPCRA0                4
  33
  34 #define GCR_CHAN_ENABLE         (1 << 31)
  35 #define GCR_TEARDOWN            (1 << 30)
  36 #define GCR_STARV_RETRY         (1 << 24)
  37 #define GCR_DESC_TYPE_HOST      (1 << 14)
  38
  39 /* DMA scheduler */
  40 #define DMA_SCHED_CTRL          0
  41 #define DMA_SCHED_CTRL_EN       (1 << 31)
  42 #define DMA_SCHED_WORD(x)       ((x) * 4 + 0x800)
  43
  44 #define SCHED_ENTRY0_CHAN(x)    ((x) << 0)
  45 #define SCHED_ENTRY0_IS_RX      (1 << 7)
  46
  47 #define SCHED_ENTRY1_CHAN(x)    ((x) << 8)
  48 #define SCHED_ENTRY1_IS_RX      (1 << 15)
  49
  50 #define SCHED_ENTRY2_CHAN(x)    ((x) << 16)
  51 #define SCHED_ENTRY2_IS_RX      (1 << 23)
  52
  53 #define SCHED_ENTRY3_CHAN(x)    ((x) << 24)
  54 #define SCHED_ENTRY3_IS_RX      (1 << 31)
  55
  56 /* Queue manager */
  57 /* 4 KiB of memory for descriptors, 2 for each endpoint */
  58 #define ALLOC_DECS_NUM          128
  59 #define DESCS_AREAS             1
  60 #define TOTAL_DESCS_NUM         (ALLOC_DECS_NUM * DESCS_AREAS)
  61 #define QMGR_SCRATCH_SIZE       (TOTAL_DESCS_NUM * 4)
  62
  63 #define QMGR_LRAM0_BASE         0x80
  64 #define QMGR_LRAM_SIZE          0x84
  65 #define QMGR_LRAM1_BASE         0x88
  66 #define QMGR_MEMBASE(x)         (0x1000 + (x) * 0x10)
  67 #define QMGR_MEMCTRL(x)         (0x1004 + (x) * 0x10)
  68 #define QMGR_MEMCTRL_IDX_SH     16
  69 #define QMGR_MEMCTRL_DESC_SH    8
  70
  71 #define QMGR_PEND(x)    (0x90 + (x) * 4)
  72
  73 #define QMGR_PENDING_SLOT_Q(x)  (x / 32)
  74 #define QMGR_PENDING_BIT_Q(x)   (x % 32)
  75
  76 #define QMGR_QUEUE_A(n) (0x2000 + (n) * 0x10)
  77 #define QMGR_QUEUE_B(n) (0x2004 + (n) * 0x10)
  78 #define QMGR_QUEUE_C(n) (0x2008 + (n) * 0x10)
  79 #define QMGR_QUEUE_D(n) (0x200c + (n) * 0x10)
  80
  81 /* Packet Descriptor */
  82 #define PD2_ZERO_LENGTH         (1 << 19)
  83
  84 struct cppi41_channel {
  85         struct dma_chan chan;
  86         struct dma_async_tx_descriptor txd;
  87         struct cppi41_dd *cdd;
  88         struct cppi41_desc *desc;
  89         dma_addr_t desc_phys;
  90         void __iomem *gcr_reg;
  91         int is_tx;
  92         u32 residue;
  93
  94         unsigned int q_num;
  95         unsigned int q_comp_num;
  96         unsigned int port_num;
  97
  98         unsigned td_retry;
  99         unsigned td_queued:1;
 100         unsigned td_seen:1;
 101         unsigned td_desc_seen:1;
 102
 103         struct list_head node;          /* Node for pending list */
 104 };
 105
 106 struct cppi41_desc {
 107         u32 pd0;
 108         u32 pd1;
 109         u32 pd2;
 110         u32 pd3;
 111         u32 pd4;
 112         u32 pd5;
 113         u32 pd6;
 114         u32 pd7;
 115 } __aligned(32);
 116
 117 struct chan_queues {
 118         u16 submit;
 119         u16 complete;
 120 };
 121
 122 struct cppi41_dd {
 123         struct dma_device ddev;
 124
 125         void *qmgr_scratch;
 126         dma_addr_t scratch_phys;
 127
 128         struct cppi41_desc *cd;
 129         dma_addr_t descs_phys;
 130         u32 first_td_desc;
 131         struct cppi41_channel *chan_busy[ALLOC_DECS_NUM];
 132
 133         void __iomem *ctrl_mem;
 134         void __iomem *sched_mem;
 135         void __iomem *qmgr_mem;
 136         unsigned int irq;
 137         const struct chan_queues *queues_rx;
 138         const struct chan_queues *queues_tx;
 139         struct chan_queues td_queue;
 140         u16 first_completion_queue;
 141         u16 qmgr_num_pend;
 142         u32 n_chans;
 143         u8 platform;
 144
 145         struct list_head pending;       /* Pending queued transfers */
 146         spinlock_t lock;                /* Lock for pending list */
 147
 148         /* context for suspend/resume */
 149         unsigned int dma_tdfdq;
 150
 151         bool is_suspended;
 152 };
 153
 154 static struct chan_queues am335x_usb_queues_tx[] = {
 155         /* USB0 ENDP 1 */
 156         [ 0] = { .submit = 32, .complete =  93},
 157         [ 1] = { .submit = 34, .complete =  94},
 158         [ 2] = { .submit = 36, .complete =  95},
 159         [ 3] = { .submit = 38, .complete =  96},
 160         [ 4] = { .submit = 40, .complete =  97},
 161         [ 5] = { .submit = 42, .complete =  98},
 162         [ 6] = { .submit = 44, .complete =  99},
 163         [ 7] = { .submit = 46, .complete = 100},
 164         [ 8] = { .submit = 48, .complete = 101},
 165         [ 9] = { .submit = 50, .complete = 102},
 166         [10] = { .submit = 52, .complete = 103},
 167         [11] = { .submit = 54, .complete = 104},
 168         [12] = { .submit = 56, .complete = 105},
 169         [13] = { .submit = 58, .complete = 106},
 170         [14] = { .submit = 60, .complete = 107},
 171
 172         /* USB1 ENDP1 */
 173         [15] = { .submit = 62, .complete = 125},
 174         [16] = { .submit = 64, .complete = 126},
 175         [17] = { .submit = 66, .complete = 127},
 176         [18] = { .submit = 68, .complete = 128},
 177         [19] = { .submit = 70, .complete = 129},
 178         [20] = { .submit = 72, .complete = 130},
 179         [21] = { .submit = 74, .complete = 131},
 180         [22] = { .submit = 76, .complete = 132},
 181         [23] = { .submit = 78, .complete = 133},
 182         [24] = { .submit = 80, .complete = 134},
 183         [25] = { .submit = 82, .complete = 135},
 184         [26] = { .submit = 84, .complete = 136},
 185         [27] = { .submit = 86, .complete = 137},
 186         [28] = { .submit = 88, .complete = 138},
 187         [29] = { .submit = 90, .complete = 139},
 188 };
 189
 190 static const struct chan_queues am335x_usb_queues_rx[] = {
 191         /* USB0 ENDP 1 */
 192         [ 0] = { .submit =  1, .complete = 109},
 193         [ 1] = { .submit =  2, .complete = 110},
 194         [ 2] = { .submit =  3, .complete = 111},
 195         [ 3] = { .submit =  4, .complete = 112},
 196         [ 4] = { .submit =  5, .complete = 113},
 197         [ 5] = { .submit =  6, .complete = 114},
 198         [ 6] = { .submit =  7, .complete = 115},
 199         [ 7] = { .submit =  8, .complete = 116},
 200         [ 8] = { .submit =  9, .complete = 117},
 201         [ 9] = { .submit = 10, .complete = 118},
 202         [10] = { .submit = 11, .complete = 119},
 203         [11] = { .submit = 12, .complete = 120},
 204         [12] = { .submit = 13, .complete = 121},
 205         [13] = { .submit = 14, .complete = 122},
 206         [14] = { .submit = 15, .complete = 123},
 207
 208         /* USB1 ENDP 1 */
 209         [15] = { .submit = 16, .complete = 141},
 210         [16] = { .submit = 17, .complete = 142},
 211         [17] = { .submit = 18, .complete = 143},
 212         [18] = { .submit = 19, .complete = 144},
 213         [19] = { .submit = 20, .complete = 145},
 214         [20] = { .submit = 21, .complete = 146},
 215         [21] = { .submit = 22, .complete = 147},
 216         [22] = { .submit = 23, .complete = 148},
 217         [23] = { .submit = 24, .complete = 149},
 218         [24] = { .submit = 25, .complete = 150},
 219         [25] = { .submit = 26, .complete = 151},
 220         [26] = { .submit = 27, .complete = 152},
 221         [27] = { .submit = 28, .complete = 153},
 222         [28] = { .submit = 29, .complete = 154},
 223         [29] = { .submit = 30, .complete = 155},
 224 };
 225
 226 static const struct chan_queues da8xx_usb_queues_tx[] = {
 227         [0] = { .submit =  16, .complete = 24},
 228         [1] = { .submit =  18, .complete = 24},
 229         [2] = { .submit =  20, .complete = 24},
 230         [3] = { .submit =  22, .complete = 24},
 231 };
 232
 233 static const struct chan_queues da8xx_usb_queues_rx[] = {
 234         [0] = { .submit =  1, .complete = 26},
 235         [1] = { .submit =  3, .complete = 26},
 236         [2] = { .submit =  5, .complete = 26},
 237         [3] = { .submit =  7, .complete = 26},
 238 };
 239
 240 struct cppi_glue_infos {
 241         const struct chan_queues *queues_rx;
 242         const struct chan_queues *queues_tx;
 243         struct chan_queues td_queue;
 244         u16 first_completion_queue;
 245         u16 qmgr_num_pend;
 246 };
 247
 248 static struct cppi41_channel *to_cpp41_chan(struct dma_chan *c)
 249 {
 250         return container_of(c, struct cppi41_channel, chan);
 251 }
 252
 253 static struct cppi41_channel *desc_to_chan(struct cppi41_dd *cdd, u32 desc)
 254 {
 255         struct cppi41_channel *c;
 256         u32 descs_size;
 257         u32 desc_num;
 258
 259         descs_size = sizeof(struct cppi41_desc) * ALLOC_DECS_NUM;
 260
 261         if (!((desc >= cdd->descs_phys) &&
 262                         (desc < (cdd->descs_phys + descs_size)))) {
 263                 return NULL;
 264         }
 265
 266         desc_num = (desc - cdd->descs_phys) / sizeof(struct cppi41_desc);
 267         BUG_ON(desc_num >= ALLOC_DECS_NUM);
 268         c = cdd->chan_busy[desc_num];
 269         cdd->chan_busy[desc_num] = NULL;
 270
 271         /* Usecount for chan_busy[], paired with push_desc_queue() */
 272         pm_runtime_put(cdd->ddev.dev);
 273
 274         return c;
 275 }
 276
 277 static void cppi_writel(u32 val, void *__iomem *mem)
 278 {
 279         __raw_writel(val, mem);
 280 }
 281
 282 static u32 cppi_readl(void *__iomem *mem)
 283 {
 284         return __raw_readl(mem);
 285 }
 286
 287 static u32 pd_trans_len(u32 val)
 288 {
 289         return val & ((1 << (DESC_LENGTH_BITS_NUM + 1)) - 1);
 290 }
 291
 292 static u32 cppi41_pop_desc(struct cppi41_dd *cdd, unsigned queue_num)
 293 {
 294         u32 desc;
 295
 296         desc = cppi_readl(cdd->qmgr_mem + QMGR_QUEUE_D(queue_num));
 297         desc &= ~0x1f;
 298         return desc;
 299 }
 300
 301 static irqreturn_t cppi41_irq(int irq, void *data)
 302 {
 303         struct cppi41_dd *cdd = data;
 304         u16 first_completion_queue = cdd->first_completion_queue;
 305         u16 qmgr_num_pend = cdd->qmgr_num_pend;
 306         struct cppi41_channel *c;
 307         int i;
 308
 309         for (i = QMGR_PENDING_SLOT_Q(first_completion_queue); i < qmgr_num_pend;
 310                         i++) {
 311                 u32 val;
 312                 u32 q_num;
 313
 314                 val = cppi_readl(cdd->qmgr_mem + QMGR_PEND(i));
 315                 if (i == QMGR_PENDING_SLOT_Q(first_completion_queue) && val) {
 316                         u32 mask;
 317                         /* set corresponding bit for completetion Q 93 */
 318                         mask = 1 << QMGR_PENDING_BIT_Q(first_completion_queue);
 319                         /* not set all bits for queues less than Q 93 */
 320                         mask--;
 321                         /* now invert and keep only Q 93+ set */
 322                         val &= ~mask;
 323                 }
 324
 325                 if (val)
 326                         __iormb();
 327
 328                 while (val) {
 329                         u32 desc, len;
 330
 331                         /*
 332                          * This should never trigger, see the comments in
 333                          * push_desc_queue()
 334                          */
 335                         WARN_ON(cdd->is_suspended);
 336
 337                         q_num = __fls(val);
 338                         val &= ~(1 << q_num);
 339                         q_num += 32 * i;
 340                         desc = cppi41_pop_desc(cdd, q_num);
 341                         c = desc_to_chan(cdd, desc);
 342                         if (WARN_ON(!c)) {
 343                                 pr_err("%s() q %d desc %08x\n", __func__,
 344                                                 q_num, desc);
 345                                 continue;
 346                         }
 347
 348                         if (c->desc->pd2 & PD2_ZERO_LENGTH)
 349                                 len = 0;
 350                         else
 351                                 len = pd_trans_len(c->desc->pd0);
 352
 353                         c->residue = pd_trans_len(c->desc->pd6) - len;
 354                         dma_cookie_complete(&c->txd);
 355                         dmaengine_desc_get_callback_invoke(&c->txd, NULL);
 356                 }
 357         }
 358         return IRQ_HANDLED;
 359 }
 360
 361 static dma_cookie_t cppi41_tx_submit(struct dma_async_tx_descriptor *tx)
 362 {
 363         dma_cookie_t cookie;
 364
 365         cookie = dma_cookie_assign(tx);
 366
 367         return cookie;
 368 }
 369
 370 static int cppi41_dma_alloc_chan_resources(struct dma_chan *chan)
 371 {
 372         struct cppi41_channel *c = to_cpp41_chan(chan);
 373         struct cppi41_dd *cdd = c->cdd;
 374         int error;
 375
 376         error = pm_runtime_get_sync(cdd->ddev.dev);
 377         if (error < 0) {
 378                 dev_err(cdd->ddev.dev, "%s pm runtime get: %i\n",
 379                         __func__, error);
 380                 pm_runtime_put_noidle(cdd->ddev.dev);
 381
 382                 return error;
 383         }
 384
 385         dma_cookie_init(chan);
 386         dma_async_tx_descriptor_init(&c->txd, chan);
 387         c->txd.tx_submit = cppi41_tx_submit;
 388
 389         if (!c->is_tx)
 390                 cppi_writel(c->q_num, c->gcr_reg + RXHPCRA0);
 391
 392         pm_runtime_mark_last_busy(cdd->ddev.dev);
 393         pm_runtime_put_autosuspend(cdd->ddev.dev);
 394
 395         return 0;
 396 }
 397
 398 static void cppi41_dma_free_chan_resources(struct dma_chan *chan)
 399 {
 400         struct cppi41_channel *c = to_cpp41_chan(chan);
 401         struct cppi41_dd *cdd = c->cdd;
 402         int error;
 403
 404         error = pm_runtime_get_sync(cdd->ddev.dev);
 405         if (error < 0) {
 406                 pm_runtime_put_noidle(cdd->ddev.dev);
 407
 408                 return;
 409         }
 410
 411         WARN_ON(!list_empty(&cdd->pending));
 412
 413         pm_runtime_mark_last_busy(cdd->ddev.dev);
 414         pm_runtime_put_autosuspend(cdd->ddev.dev);
 415 }
 416
 417 static enum dma_status cppi41_dma_tx_status(struct dma_chan *chan,
 418         dma_cookie_t cookie, struct dma_tx_state *txstate)
 419 {
 420         struct cppi41_channel *c = to_cpp41_chan(chan);
 421         enum dma_status ret;
 422
 423         ret = dma_cookie_status(chan, cookie, txstate);
 424
 425         dma_set_residue(txstate, c->residue);
 426
 427         return ret;
 428 }
 429
 430 static void push_desc_queue(struct cppi41_channel *c)
 431 {
 432         struct cppi41_dd *cdd = c->cdd;
 433         u32 desc_num;
 434         u32 desc_phys;
 435         u32 reg;
 436
 437         c->residue = 0;
 438
 439         reg = GCR_CHAN_ENABLE;
 440         if (!c->is_tx) {
 441                 reg |= GCR_STARV_RETRY;
 442                 reg |= GCR_DESC_TYPE_HOST;
 443                 reg |= c->q_comp_num;
 444         }
 445
 446         cppi_writel(reg, c->gcr_reg);
 447
 448         /*
 449          * We don't use writel() but __raw_writel() so we have to make sure
 450          * that the DMA descriptor in coherent memory made to the main memory
 451          * before starting the dma engine.
 452          */
 453         __iowmb();
 454
 455         /*
 456          * DMA transfers can take at least 200ms to complete with USB mass
 457          * storage connected. To prevent autosuspend timeouts, we must use
 458          * pm_runtime_get/put() when chan_busy[] is modified. This will get
 459          * cleared in desc_to_chan() or cppi41_stop_chan() depending on the
 460          * outcome of the transfer.
 461          */
 462         pm_runtime_get(cdd->ddev.dev);
 463
 464         desc_phys = lower_32_bits(c->desc_phys);
 465         desc_num = (desc_phys - cdd->descs_phys) / sizeof(struct cppi41_desc);
 466         WARN_ON(cdd->chan_busy[desc_num]);
 467         cdd->chan_busy[desc_num] = c;
 468
 469         reg = (sizeof(struct cppi41_desc) - 24) / 4;
 470         reg |= desc_phys;
 471         cppi_writel(reg, cdd->qmgr_mem + QMGR_QUEUE_D(c->q_num));
 472 }
 473
 474 /*
 475  * Caller must hold cdd->lock to prevent push_desc_queue()
 476  * getting called out of order. We have both cppi41_dma_issue_pending()
 477  * and cppi41_runtime_resume() call this function.
 478  */
 479 static void cppi41_run_queue(struct cppi41_dd *cdd)
 480 {
 481         struct cppi41_channel *c, *_c;
 482
 483         list_for_each_entry_safe(c, _c, &cdd->pending, node) {
 484                 push_desc_queue(c);
 485                 list_del(&c->node);
 486         }
 487 }
 488
 489 static void cppi41_dma_issue_pending(struct dma_chan *chan)
 490 {
 491         struct cppi41_channel *c = to_cpp41_chan(chan);
 492         struct cppi41_dd *cdd = c->cdd;
 493         unsigned long flags;
 494         int error;
 495
 496         error = pm_runtime_get(cdd->ddev.dev);
 497         if ((error != -EINPROGRESS) && error < 0) {
 498                 pm_runtime_put_noidle(cdd->ddev.dev);
 499                 dev_err(cdd->ddev.dev, "Failed to pm_runtime_get: %i\n",
 500                         error);
 501
 502                 return;
 503         }
 504
 505         spin_lock_irqsave(&cdd->lock, flags);
 506         list_add_tail(&c->node, &cdd->pending);
 507         if (!cdd->is_suspended)
 508                 cppi41_run_queue(cdd);
 509         spin_unlock_irqrestore(&cdd->lock, flags);
 510
 511         pm_runtime_mark_last_busy(cdd->ddev.dev);
 512         pm_runtime_put_autosuspend(cdd->ddev.dev);
 513 }
 514
 515 static u32 get_host_pd0(u32 length)
 516 {
 517         u32 reg;
 518
 519         reg = DESC_TYPE_HOST << DESC_TYPE;
 520         reg |= length;
 521
 522         return reg;
 523 }
 524
 525 static u32 get_host_pd1(struct cppi41_channel *c)
 526 {
 527         u32 reg;
 528
 529         reg = 0;
 530
 531         return reg;
 532 }
 533
 534 static u32 get_host_pd2(struct cppi41_channel *c)
 535 {
 536         u32 reg;
 537
 538         reg = DESC_TYPE_USB;
 539         reg |= c->q_comp_num;
 540
 541         return reg;
 542 }
 543
 544 static u32 get_host_pd3(u32 length)
 545 {
 546         u32 reg;
 547
 548         /* PD3 = packet size */
 549         reg = length;
 550
 551         return reg;
 552 }
 553
 554 static u32 get_host_pd6(u32 length)
 555 {
 556         u32 reg;
 557
 558         /* PD6 buffer size */
 559         reg = DESC_PD_COMPLETE;
 560         reg |= length;
 561
 562         return reg;
 563 }
 564
 565 static u32 get_host_pd4_or_7(u32 addr)
 566 {
 567         u32 reg;
 568
 569         reg = addr;
 570
 571         return reg;
 572 }
 573
 574 static u32 get_host_pd5(void)
 575 {
 576         u32 reg;
 577
 578         reg = 0;
 579
 580         return reg;
 581 }
 582
 583 static struct dma_async_tx_descriptor *cppi41_dma_prep_slave_sg(
 584         struct dma_chan *chan, struct scatterlist *sgl, unsigned sg_len,
 585         enum dma_transfer_direction dir, unsigned long tx_flags, void *context)
 586 {
 587         struct cppi41_channel *c = to_cpp41_chan(chan);
 588         struct cppi41_desc *d;
 589         struct scatterlist *sg;
 590         unsigned int i;
 591
 592         d = c->desc;
 593         for_each_sg(sgl, sg, sg_len, i) {
 594                 u32 addr;
 595                 u32 len;
 596
 597                 /* We need to use more than one desc once musb supports sg */
 598                 addr = lower_32_bits(sg_dma_address(sg));
 599                 len = sg_dma_len(sg);
 600
 601                 d->pd0 = get_host_pd0(len);
 602                 d->pd1 = get_host_pd1(c);
 603                 d->pd2 = get_host_pd2(c);
 604                 d->pd3 = get_host_pd3(len);
 605                 d->pd4 = get_host_pd4_or_7(addr);
 606                 d->pd5 = get_host_pd5();
 607                 d->pd6 = get_host_pd6(len);
 608                 d->pd7 = get_host_pd4_or_7(addr);
 609
 610                 d++;
 611         }
 612
 613         return &c->txd;
 614 }
 615
 616 static void cppi41_compute_td_desc(struct cppi41_desc *d)
 617 {
 618         d->pd0 = DESC_TYPE_TEARD << DESC_TYPE;
 619 }
 620
 621 static int cppi41_tear_down_chan(struct cppi41_channel *c)
 622 {
 623         struct dmaengine_result abort_result;
 624         struct cppi41_dd *cdd = c->cdd;
 625         struct cppi41_desc *td;
 626         u32 reg;
 627         u32 desc_phys;
 628         u32 td_desc_phys;
 629
 630         td = cdd->cd;
 631         td += cdd->first_td_desc;
 632
 633         td_desc_phys = cdd->descs_phys;
 634         td_desc_phys += cdd->first_td_desc * sizeof(struct cppi41_desc);
 635
 636         if (!c->td_queued) {
 637                 cppi41_compute_td_desc(td);
 638                 __iowmb();
 639
 640                 reg = (sizeof(struct cppi41_desc) - 24) / 4;
 641                 reg |= td_desc_phys;
 642                 cppi_writel(reg, cdd->qmgr_mem +
 643                                 QMGR_QUEUE_D(cdd->td_queue.submit));
 644
 645                 reg = GCR_CHAN_ENABLE;
 646                 if (!c->is_tx) {
 647                         reg |= GCR_STARV_RETRY;
 648                         reg |= GCR_DESC_TYPE_HOST;
 649                         reg |= cdd->td_queue.complete;
 650                 }
 651                 reg |= GCR_TEARDOWN;
 652                 cppi_writel(reg, c->gcr_reg);
 653                 c->td_queued = 1;
 654                 c->td_retry = 500;
 655         }
 656
 657         if (!c->td_seen || !c->td_desc_seen) {
 658
 659                 desc_phys = cppi41_pop_desc(cdd, cdd->td_queue.complete);
 660                 if (!desc_phys && c->is_tx)
 661                         desc_phys = cppi41_pop_desc(cdd, c->q_comp_num);
 662
 663                 if (desc_phys == c->desc_phys) {
 664                         c->td_desc_seen = 1;
 665
 666                 } else if (desc_phys == td_desc_phys) {
 667                         u32 pd0;
 668
 669                         __iormb();
 670                         pd0 = td->pd0;
 671                         WARN_ON((pd0 >> DESC_TYPE) != DESC_TYPE_TEARD);
 672                         WARN_ON(!c->is_tx && !(pd0 & TD_DESC_IS_RX));
 673                         WARN_ON((pd0 & 0x1f) != c->port_num);
 674                         c->td_seen = 1;
 675                 } else if (desc_phys) {
 676                         WARN_ON_ONCE(1);
 677                 }
 678         }
 679         c->td_retry--;
 680         /*
 681          * If the TX descriptor / channel is in use, the caller needs to poke
 682          * his TD bit multiple times. After that he hardware releases the
 683          * transfer descriptor followed by TD descriptor. Waiting seems not to
 684          * cause any difference.
 685          * RX seems to be thrown out right away. However once the TearDown
 686          * descriptor gets through we are done. If we have seens the transfer
 687          * descriptor before the TD we fetch it from enqueue, it has to be
 688          * there waiting for us.
 689          */
 690         if (!c->td_seen && c->td_retry) {
 691                 udelay(1);
 692                 return -EAGAIN;
 693         }
 694         WARN_ON(!c->td_retry);
 695
 696         if (!c->td_desc_seen) {
 697                 desc_phys = cppi41_pop_desc(cdd, c->q_num);
 698                 if (!desc_phys)
 699                         desc_phys = cppi41_pop_desc(cdd, c->q_comp_num);
 700                 WARN_ON(!desc_phys);
 701         }
 702
 703         c->td_queued = 0;
 704         c->td_seen = 0;
 705         c->td_desc_seen = 0;
 706         cppi_writel(0, c->gcr_reg);
 707
 708         /* Invoke the callback to do the necessary clean-up */
 709         abort_result.result = DMA_TRANS_ABORTED;
 710         dma_cookie_complete(&c->txd);
 711         dmaengine_desc_get_callback_invoke(&c->txd, &abort_result);
 712
 713         return 0;
 714 }
 715
 716 static int cppi41_stop_chan(struct dma_chan *chan)
 717 {
 718         struct cppi41_channel *c = to_cpp41_chan(chan);
 719         struct cppi41_dd *cdd = c->cdd;
 720         u32 desc_num;
 721         u32 desc_phys;
 722         int ret;
 723
 724         desc_phys = lower_32_bits(c->desc_phys);
 725         desc_num = (desc_phys - cdd->descs_phys) / sizeof(struct cppi41_desc);
 726         if (!cdd->chan_busy[desc_num]) {
 727                 struct cppi41_channel *cc, *_ct;
 728
 729                 /*
 730                  * channels might still be in the pendling list if
 731                  * cppi41_dma_issue_pending() is called after
 732                  * cppi41_runtime_suspend() is called
 733                  */
 734                 list_for_each_entry_safe(cc, _ct, &cdd->pending, node) {
 735                         if (cc != c)
 736                                 continue;
 737                         list_del(&cc->node);
 738                         break;
 739                 }
 740                 return 0;
 741         }
 742
 743         ret = cppi41_tear_down_chan(c);
 744         if (ret)
 745                 return ret;
 746
 747         WARN_ON(!cdd->chan_busy[desc_num]);
 748         cdd->chan_busy[desc_num] = NULL;
 749
 750         /* Usecount for chan_busy[], paired with push_desc_queue() */
 751         pm_runtime_put(cdd->ddev.dev);
 752
 753         return 0;
 754 }
 755
 756 static int cppi41_add_chans(struct device *dev, struct cppi41_dd *cdd)
 757 {
 758         struct cppi41_channel *cchan, *chans;
 759         int i;
 760         u32 n_chans = cdd->n_chans;
 761
 762         /*
 763          * The channels can only be used as TX or as RX. So we add twice
 764          * that much dma channels because USB can only do RX or TX.
 765          */
 766         n_chans *= 2;
 767
 768         chans = devm_kcalloc(dev, n_chans, sizeof(*chans), GFP_KERNEL);
 769         if (!chans)
 770                 return -ENOMEM;
 771
 772         for (i = 0; i < n_chans; i++) {
 773                 cchan = &chans[i];
 774
 775                 cchan->cdd = cdd;
 776                 if (i & 1) {
 777                         cchan->gcr_reg = cdd->ctrl_mem + DMA_TXGCR(i >> 1);
 778                         cchan->is_tx = 1;
 779                 } else {
 780                         cchan->gcr_reg = cdd->ctrl_mem + DMA_RXGCR(i >> 1);
 781                         cchan->is_tx = 0;
 782                 }
 783                 cchan->port_num = i >> 1;
 784                 cchan->desc = &cdd->cd[i];
 785                 cchan->desc_phys = cdd->descs_phys;
 786                 cchan->desc_phys += i * sizeof(struct cppi41_desc);
 787                 cchan->chan.device = &cdd->ddev;
 788                 list_add_tail(&cchan->chan.device_node, &cdd->ddev.channels);
 789         }
 790         cdd->first_td_desc = n_chans;
 791
 792         return 0;
 793 }
 794
 795 static void purge_descs(struct device *dev, struct cppi41_dd *cdd)
 796 {
 797         unsigned int mem_decs;
 798         int i;
 799
 800         mem_decs = ALLOC_DECS_NUM * sizeof(struct cppi41_desc);
 801
 802         for (i = 0; i < DESCS_AREAS; i++) {
 803
 804                 cppi_writel(0, cdd->qmgr_mem + QMGR_MEMBASE(i));
 805                 cppi_writel(0, cdd->qmgr_mem + QMGR_MEMCTRL(i));
 806
 807                 dma_free_coherent(dev, mem_decs, cdd->cd,
 808                                 cdd->descs_phys);
 809         }
 810 }
 811
 812 static void disable_sched(struct cppi41_dd *cdd)
 813 {
 814         cppi_writel(0, cdd->sched_mem + DMA_SCHED_CTRL);
 815 }
 816
 817 static void deinit_cppi41(struct device *dev, struct cppi41_dd *cdd)
 818 {
 819         disable_sched(cdd);
 820
 821         purge_descs(dev, cdd);
 822
 823         cppi_writel(0, cdd->qmgr_mem + QMGR_LRAM0_BASE);
 824         cppi_writel(0, cdd->qmgr_mem + QMGR_LRAM0_BASE);
 825         dma_free_coherent(dev, QMGR_SCRATCH_SIZE, cdd->qmgr_scratch,
 826                         cdd->scratch_phys);
 827 }
 828
 829 static int init_descs(struct device *dev, struct cppi41_dd *cdd)
 830 {
 831         unsigned int desc_size;
 832         unsigned int mem_decs;
 833         int i;
 834         u32 reg;
 835         u32 idx;
 836
 837         BUILD_BUG_ON(sizeof(struct cppi41_desc) &
 838                         (sizeof(struct cppi41_desc) - 1));
 839         BUILD_BUG_ON(sizeof(struct cppi41_desc) < 32);
 840         BUILD_BUG_ON(ALLOC_DECS_NUM < 32);
 841
 842         desc_size = sizeof(struct cppi41_desc);
 843         mem_decs = ALLOC_DECS_NUM * desc_size;
 844
 845         idx = 0;
 846         for (i = 0; i < DESCS_AREAS; i++) {
 847
 848                 reg = idx << QMGR_MEMCTRL_IDX_SH;
 849                 reg |= (ilog2(desc_size) - 5) << QMGR_MEMCTRL_DESC_SH;
 850                 reg |= ilog2(ALLOC_DECS_NUM) - 5;
 851
 852                 BUILD_BUG_ON(DESCS_AREAS != 1);
 853                 cdd->cd = dma_alloc_coherent(dev, mem_decs,
 854                                 &cdd->descs_phys, GFP_KERNEL);
 855                 if (!cdd->cd)
 856                         return -ENOMEM;
 857
 858                 cppi_writel(cdd->descs_phys, cdd->qmgr_mem + QMGR_MEMBASE(i));
 859                 cppi_writel(reg, cdd->qmgr_mem + QMGR_MEMCTRL(i));
 860
 861                 idx += ALLOC_DECS_NUM;
 862         }
 863         return 0;
 864 }
 865
 866 static void init_sched(struct cppi41_dd *cdd)
 867 {
 868         unsigned ch;
 869         unsigned word;
 870         u32 reg;
 871
 872         word = 0;
 873         cppi_writel(0, cdd->sched_mem + DMA_SCHED_CTRL);
 874         for (ch = 0; ch < cdd->n_chans; ch += 2) {
 875
 876                 reg = SCHED_ENTRY0_CHAN(ch);
 877                 reg |= SCHED_ENTRY1_CHAN(ch) | SCHED_ENTRY1_IS_RX;
 878
 879                 reg |= SCHED_ENTRY2_CHAN(ch + 1);
 880                 reg |= SCHED_ENTRY3_CHAN(ch + 1) | SCHED_ENTRY3_IS_RX;
 881                 cppi_writel(reg, cdd->sched_mem + DMA_SCHED_WORD(word));
 882                 word++;
 883         }
 884         reg = cdd->n_chans * 2 - 1;
 885         reg |= DMA_SCHED_CTRL_EN;
 886         cppi_writel(reg, cdd->sched_mem + DMA_SCHED_CTRL);
 887 }
 888
 889 static int init_cppi41(struct device *dev, struct cppi41_dd *cdd)
 890 {
 891         int ret;
 892
 893         BUILD_BUG_ON(QMGR_SCRATCH_SIZE > ((1 << 14) - 1));
 894         cdd->qmgr_scratch = dma_alloc_coherent(dev, QMGR_SCRATCH_SIZE,
 895                         &cdd->scratch_phys, GFP_KERNEL);
 896         if (!cdd->qmgr_scratch)
 897                 return -ENOMEM;
 898
 899         cppi_writel(cdd->scratch_phys, cdd->qmgr_mem + QMGR_LRAM0_BASE);
 900         cppi_writel(TOTAL_DESCS_NUM, cdd->qmgr_mem + QMGR_LRAM_SIZE);
 901         cppi_writel(0, cdd->qmgr_mem + QMGR_LRAM1_BASE);
 902
 903         ret = init_descs(dev, cdd);
 904         if (ret)
 905                 goto err_td;
 906
 907         cppi_writel(cdd->td_queue.submit, cdd->ctrl_mem + DMA_TDFDQ);
 908         init_sched(cdd);
 909
 910         return 0;
 911 err_td:
 912         deinit_cppi41(dev, cdd);
 913         return ret;
 914 }
 915
 916 static struct platform_driver cpp41_dma_driver;
 917 /*
 918  * The param format is:
 919  * X Y
 920  * X: Port
 921  * Y: 0 = RX else TX
 922  */
 923 #define INFO_PORT       0
 924 #define INFO_IS_TX      1
 925
 926 static bool cpp41_dma_filter_fn(struct dma_chan *chan, void *param)
 927 {
 928         struct cppi41_channel *cchan;
 929         struct cppi41_dd *cdd;
 930         const struct chan_queues *queues;
 931         u32 *num = param;
 932
 933         if (chan->device->dev->driver != &cpp41_dma_driver.driver)
 934                 return false;
 935
 936         cchan = to_cpp41_chan(chan);
 937
 938         if (cchan->port_num != num[INFO_PORT])
 939                 return false;
 940
 941         if (cchan->is_tx && !num[INFO_IS_TX])
 942                 return false;
 943         cdd = cchan->cdd;
 944         if (cchan->is_tx)
 945                 queues = cdd->queues_tx;
 946         else
 947                 queues = cdd->queues_rx;
 948
 949         BUILD_BUG_ON(ARRAY_SIZE(am335x_usb_queues_rx) !=
 950                      ARRAY_SIZE(am335x_usb_queues_tx));
 951         if (WARN_ON(cchan->port_num >= ARRAY_SIZE(am335x_usb_queues_rx)))
 952                 return false;
 953
 954         cchan->q_num = queues[cchan->port_num].submit;
 955         cchan->q_comp_num = queues[cchan->port_num].complete;
 956         return true;
 957 }
 958
 959 static struct of_dma_filter_info cpp41_dma_info = {
 960         .filter_fn = cpp41_dma_filter_fn,
 961 };
 962
 963 static struct dma_chan *cppi41_dma_xlate(struct of_phandle_args *dma_spec,
 964                 struct of_dma *ofdma)
 965 {
 966         int count = dma_spec->args_count;
 967         struct of_dma_filter_info *info = ofdma->of_dma_data;
 968
 969         if (!info || !info->filter_fn)
 970                 return NULL;
 971
 972         if (count != 2)
 973                 return NULL;
 974
 975         return dma_request_channel(info->dma_cap, info->filter_fn,
 976                         &dma_spec->args[0]);
 977 }
 978
 979 static const struct cppi_glue_infos am335x_usb_infos = {
 980         .queues_rx = am335x_usb_queues_rx,
 981         .queues_tx = am335x_usb_queues_tx,
 982         .td_queue = { .submit = 31, .complete = 0 },
 983         .first_completion_queue = 93,
 984         .qmgr_num_pend = 5,
 985 };
 986
 987 static const struct cppi_glue_infos da8xx_usb_infos = {
 988         .queues_rx = da8xx_usb_queues_rx,
 989         .queues_tx = da8xx_usb_queues_tx,
 990         .td_queue = { .submit = 31, .complete = 0 },
 991         .first_completion_queue = 24,
 992         .qmgr_num_pend = 2,
 993 };
 994
 995 static const struct of_device_id cppi41_dma_ids[] = {
 996         { .compatible = "ti,am3359-cppi41", .data = &am335x_usb_infos},
 997         { .compatible = "ti,da830-cppi41", .data = &da8xx_usb_infos},
 998         {},
 999 };
1000 MODULE_DEVICE_TABLE(of, cppi41_dma_ids);
1001
1002 static const struct cppi_glue_infos *get_glue_info(struct device *dev)
1003 {
1004         const struct of_device_id *of_id;
1005
1006         of_id = of_match_node(cppi41_dma_ids, dev->of_node);
1007         if (!of_id)
1008                 return NULL;
1009         return of_id->data;
1010 }
1011
1012 #define CPPI41_DMA_BUSWIDTHS    (BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
1013                                 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
1014                                 BIT(DMA_SLAVE_BUSWIDTH_3_BYTES) | \
1015                                 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES))
1016
1017 static int cppi41_dma_probe(struct platform_device *pdev)
1018 {
1019         struct cppi41_dd *cdd;
1020         struct device *dev = &pdev->dev;
1021         const struct cppi_glue_infos *glue_info;
1022         struct resource *mem;
1023         int index;
1024         int irq;
1025         int ret;
1026
1027         glue_info = get_glue_info(dev);
1028         if (!glue_info)
1029                 return -EINVAL;
1030
1031         cdd = devm_kzalloc(&pdev->dev, sizeof(*cdd), GFP_KERNEL);
1032         if (!cdd)
1033                 return -ENOMEM;
1034
1035         dma_cap_set(DMA_SLAVE, cdd->ddev.cap_mask);
1036         cdd->ddev.device_alloc_chan_resources = cppi41_dma_alloc_chan_resources;
1037         cdd->ddev.device_free_chan_resources = cppi41_dma_free_chan_resources;
1038         cdd->ddev.device_tx_status = cppi41_dma_tx_status;
1039         cdd->ddev.device_issue_pending = cppi41_dma_issue_pending;
1040         cdd->ddev.device_prep_slave_sg = cppi41_dma_prep_slave_sg;
1041         cdd->ddev.device_terminate_all = cppi41_stop_chan;
1042         cdd->ddev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1043         cdd->ddev.src_addr_widths = CPPI41_DMA_BUSWIDTHS;
1044         cdd->ddev.dst_addr_widths = CPPI41_DMA_BUSWIDTHS;
1045         cdd->ddev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
1046         cdd->ddev.dev = dev;
1047         INIT_LIST_HEAD(&cdd->ddev.channels);
1048         cpp41_dma_info.dma_cap = cdd->ddev.cap_mask;
1049
1050         index = of_property_match_string(dev->of_node,
1051                                          "reg-names", "controller");
1052         if (index < 0)
1053                 return index;
1054
1055         mem = platform_get_resource(pdev, IORESOURCE_MEM, index);
1056         cdd->ctrl_mem = devm_ioremap_resource(dev, mem);
1057         if (IS_ERR(cdd->ctrl_mem))
1058                 return PTR_ERR(cdd->ctrl_mem);
1059
1060         mem = platform_get_resource(pdev, IORESOURCE_MEM, index + 1);
1061         cdd->sched_mem = devm_ioremap_resource(dev, mem);
1062         if (IS_ERR(cdd->sched_mem))
1063                 return PTR_ERR(cdd->sched_mem);
1064
1065         mem = platform_get_resource(pdev, IORESOURCE_MEM, index + 2);
1066         cdd->qmgr_mem = devm_ioremap_resource(dev, mem);
1067         if (IS_ERR(cdd->qmgr_mem))
1068                 return PTR_ERR(cdd->qmgr_mem);
1069
1070         spin_lock_init(&cdd->lock);
1071         INIT_LIST_HEAD(&cdd->pending);
1072
1073         platform_set_drvdata(pdev, cdd);
1074
1075         pm_runtime_enable(dev);
1076         pm_runtime_set_autosuspend_delay(dev, 100);
1077         pm_runtime_use_autosuspend(dev);
1078         ret = pm_runtime_get_sync(dev);
1079         if (ret < 0)
1080                 goto err_get_sync;
1081
1082         cdd->queues_rx = glue_info->queues_rx;
1083         cdd->queues_tx = glue_info->queues_tx;
1084         cdd->td_queue = glue_info->td_queue;
1085         cdd->qmgr_num_pend = glue_info->qmgr_num_pend;
1086         cdd->first_completion_queue = glue_info->first_completion_queue;
1087
1088         ret = of_property_read_u32(dev->of_node,
1089                                    "#dma-channels", &cdd->n_chans);
1090         if (ret)
1091                 goto err_get_n_chans;
1092
1093         ret = init_cppi41(dev, cdd);
1094         if (ret)
1095                 goto err_init_cppi;
1096
1097         ret = cppi41_add_chans(dev, cdd);
1098         if (ret)
1099                 goto err_chans;
1100
1101         irq = irq_of_parse_and_map(dev->of_node, 0);
1102         if (!irq) {
1103                 ret = -EINVAL;
1104                 goto err_chans;
1105         }
1106
1107         ret = devm_request_irq(&pdev->dev, irq, cppi41_irq, IRQF_SHARED,
1108                         dev_name(dev), cdd);
1109         if (ret)
1110                 goto err_chans;
1111         cdd->irq = irq;
1112
1113         ret = dma_async_device_register(&cdd->ddev);
1114         if (ret)
1115                 goto err_chans;
1116
1117         ret = of_dma_controller_register(dev->of_node,
1118                         cppi41_dma_xlate, &cpp41_dma_info);
1119         if (ret)
1120                 goto err_of;
1121
1122         pm_runtime_mark_last_busy(dev);
1123         pm_runtime_put_autosuspend(dev);
1124
1125         return 0;
1126 err_of:
1127         dma_async_device_unregister(&cdd->ddev);
1128 err_chans:
1129         deinit_cppi41(dev, cdd);
1130 err_init_cppi:
1131         pm_runtime_dont_use_autosuspend(dev);
1132 err_get_n_chans:
1133 err_get_sync:
1134         pm_runtime_put_sync(dev);
1135         pm_runtime_disable(dev);
1136         return ret;
1137 }
1138
1139 static int cppi41_dma_remove(struct platform_device *pdev)
1140 {
1141         struct cppi41_dd *cdd = platform_get_drvdata(pdev);
1142         int error;
1143
1144         error = pm_runtime_get_sync(&pdev->dev);
1145         if (error < 0)
1146                 dev_err(&pdev->dev, "%s could not pm_runtime_get: %i\n",
1147                         __func__, error);
1148         of_dma_controller_free(pdev->dev.of_node);
1149         dma_async_device_unregister(&cdd->ddev);
1150
1151         devm_free_irq(&pdev->dev, cdd->irq, cdd);
1152         deinit_cppi41(&pdev->dev, cdd);
1153         pm_runtime_dont_use_autosuspend(&pdev->dev);
1154         pm_runtime_put_sync(&pdev->dev);
1155         pm_runtime_disable(&pdev->dev);
1156         return 0;
1157 }
1158
1159 static int __maybe_unused cppi41_suspend(struct device *dev)
1160 {
1161         struct cppi41_dd *cdd = dev_get_drvdata(dev);
1162
1163         cdd->dma_tdfdq = cppi_readl(cdd->ctrl_mem + DMA_TDFDQ);
1164         disable_sched(cdd);
1165
1166         return 0;
1167 }
1168
1169 static int __maybe_unused cppi41_resume(struct device *dev)
1170 {
1171         struct cppi41_dd *cdd = dev_get_drvdata(dev);
1172         struct cppi41_channel *c;
1173         int i;
1174
1175         for (i = 0; i < DESCS_AREAS; i++)
1176                 cppi_writel(cdd->descs_phys, cdd->qmgr_mem + QMGR_MEMBASE(i));
1177
1178         list_for_each_entry(c, &cdd->ddev.channels, chan.device_node)
1179                 if (!c->is_tx)
1180                         cppi_writel(c->q_num, c->gcr_reg + RXHPCRA0);
1181
1182         init_sched(cdd);
1183
1184         cppi_writel(cdd->dma_tdfdq, cdd->ctrl_mem + DMA_TDFDQ);
1185         cppi_writel(cdd->scratch_phys, cdd->qmgr_mem + QMGR_LRAM0_BASE);
1186         cppi_writel(QMGR_SCRATCH_SIZE, cdd->qmgr_mem + QMGR_LRAM_SIZE);
1187         cppi_writel(0, cdd->qmgr_mem + QMGR_LRAM1_BASE);
1188
1189         return 0;
1190 }
1191
1192 static int __maybe_unused cppi41_runtime_suspend(struct device *dev)
1193 {
1194         struct cppi41_dd *cdd = dev_get_drvdata(dev);
1195         unsigned long flags;
1196
1197         spin_lock_irqsave(&cdd->lock, flags);
1198         cdd->is_suspended = true;
1199         WARN_ON(!list_empty(&cdd->pending));
1200         spin_unlock_irqrestore(&cdd->lock, flags);
1201
1202         return 0;
1203 }
1204
1205 static int __maybe_unused cppi41_runtime_resume(struct device *dev)
1206 {
1207         struct cppi41_dd *cdd = dev_get_drvdata(dev);
1208         unsigned long flags;
1209
1210         spin_lock_irqsave(&cdd->lock, flags);
1211         cdd->is_suspended = false;
1212         cppi41_run_queue(cdd);
1213         spin_unlock_irqrestore(&cdd->lock, flags);
1214
1215         return 0;
1216 }
1217
1218 static const struct dev_pm_ops cppi41_pm_ops = {
1219         SET_LATE_SYSTEM_SLEEP_PM_OPS(cppi41_suspend, cppi41_resume)
1220         SET_RUNTIME_PM_OPS(cppi41_runtime_suspend,
1221                            cppi41_runtime_resume,
1222                            NULL)
1223 };
1224
1225 static struct platform_driver cpp41_dma_driver = {
1226         .probe  = cppi41_dma_probe,
1227         .remove = cppi41_dma_remove,
1228         .driver = {
1229                 .name = "cppi41-dma-engine",
1230                 .pm = &cppi41_pm_ops,
1231                 .of_match_table = of_match_ptr(cppi41_dma_ids),
1232         },
1233 };
1234
1235 module_platform_driver(cpp41_dma_driver);
1236 MODULE_LICENSE("GPL");
1237 MODULE_AUTHOR("Sebastian Andrzej Siewior <bigeasy@linutronix.de>");