drivers/net/ethernet/ti/davinci_cpdma.c

   1 /*
   2  * Texas Instruments CPDMA Driver
   3  *
   4  * Copyright (C) 2010 Texas Instruments
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation version 2.
   9  *
  10  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
  11  * kind, whether express or implied; without even the implied warranty
  12  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15 #include <linux/kernel.h>
  16 #include <linux/spinlock.h>
  17 #include <linux/device.h>
  18 #include <linux/slab.h>
  19 #include <linux/err.h>
  20 #include <linux/dma-mapping.h>
  21 #include <linux/io.h>
  22
  23 #include "davinci_cpdma.h"
  24
  25 /* DMA Registers */
  26 #define CPDMA_TXIDVER           0x00
  27 #define CPDMA_TXCONTROL         0x04
  28 #define CPDMA_TXTEARDOWN        0x08
  29 #define CPDMA_RXIDVER           0x10
  30 #define CPDMA_RXCONTROL         0x14
  31 #define CPDMA_SOFTRESET         0x1c
  32 #define CPDMA_RXTEARDOWN        0x18
  33 #define CPDMA_TXINTSTATRAW      0x80
  34 #define CPDMA_TXINTSTATMASKED   0x84
  35 #define CPDMA_TXINTMASKSET      0x88
  36 #define CPDMA_TXINTMASKCLEAR    0x8c
  37 #define CPDMA_MACINVECTOR       0x90
  38 #define CPDMA_MACEOIVECTOR      0x94
  39 #define CPDMA_RXINTSTATRAW      0xa0
  40 #define CPDMA_RXINTSTATMASKED   0xa4
  41 #define CPDMA_RXINTMASKSET      0xa8
  42 #define CPDMA_RXINTMASKCLEAR    0xac
  43 #define CPDMA_DMAINTSTATRAW     0xb0
  44 #define CPDMA_DMAINTSTATMASKED  0xb4
  45 #define CPDMA_DMAINTMASKSET     0xb8
  46 #define CPDMA_DMAINTMASKCLEAR   0xbc
  47 #define CPDMA_DMAINT_HOSTERR    BIT(1)
  48
  49 /* the following exist only if has_ext_regs is set */
  50 #define CPDMA_DMACONTROL        0x20
  51 #define CPDMA_DMASTATUS         0x24
  52 #define CPDMA_RXBUFFOFS         0x28
  53 #define CPDMA_EM_CONTROL        0x2c
  54
  55 /* Descriptor mode bits */
  56 #define CPDMA_DESC_SOP          BIT(31)
  57 #define CPDMA_DESC_EOP          BIT(30)
  58 #define CPDMA_DESC_OWNER        BIT(29)
  59 #define CPDMA_DESC_EOQ          BIT(28)
  60 #define CPDMA_DESC_TD_COMPLETE  BIT(27)
  61 #define CPDMA_DESC_PASS_CRC     BIT(26)
  62
  63 #define CPDMA_TEARDOWN_VALUE    0xfffffffc
  64
  65 struct cpdma_desc {
  66         /* hardware fields */
  67         u32                     hw_next;
  68         u32                     hw_buffer;
  69         u32                     hw_len;
  70         u32                     hw_mode;
  71         /* software fields */
  72         void                    *sw_token;
  73         u32                     sw_buffer;
  74         u32                     sw_len;
  75 };
  76
  77 struct cpdma_desc_pool {
  78         u32                     phys;
  79         u32                     hw_addr;
  80         void __iomem            *iomap;         /* ioremap map */
  81         void                    *cpumap;        /* dma_alloc map */
  82         int                     desc_size, mem_size;
  83         int                     num_desc, used_desc;
  84         unsigned long           *bitmap;
  85         struct device           *dev;
  86         spinlock_t              lock;
  87 };
  88
  89 enum cpdma_state {
  90         CPDMA_STATE_IDLE,
  91         CPDMA_STATE_ACTIVE,
  92         CPDMA_STATE_TEARDOWN,
  93 };
  94
  95 const char *cpdma_state_str[] = { "idle", "active", "teardown" };
  96
  97 struct cpdma_ctlr {
  98         enum cpdma_state        state;
  99         struct cpdma_params     params;
 100         struct device           *dev;
 101         struct cpdma_desc_pool  *pool;
 102         spinlock_t              lock;
 103         struct cpdma_chan       *channels[2 * CPDMA_MAX_CHANNELS];
 104 };
 105
 106 struct cpdma_chan {
 107         enum cpdma_state                state;
 108         struct cpdma_ctlr               *ctlr;
 109         int                             chan_num;
 110         spinlock_t                      lock;
 111         struct cpdma_desc __iomem       *head, *tail;
 112         int                             count;
 113         void __iomem                    *hdp, *cp, *rxfree;
 114         u32                             mask;
 115         cpdma_handler_fn                handler;
 116         enum dma_data_direction         dir;
 117         struct cpdma_chan_stats         stats;
 118         /* offsets into dmaregs */
 119         int     int_set, int_clear, td;
 120 };
 121
 122 /* The following make access to common cpdma_ctlr params more readable */
 123 #define dmaregs         params.dmaregs
 124 #define num_chan        params.num_chan
 125
 126 /* various accessors */
 127 #define dma_reg_read(ctlr, ofs)         __raw_readl((ctlr)->dmaregs + (ofs))
 128 #define chan_read(chan, fld)            __raw_readl((chan)->fld)
 129 #define desc_read(desc, fld)            __raw_readl(&(desc)->fld)
 130 #define dma_reg_write(ctlr, ofs, v)     __raw_writel(v, (ctlr)->dmaregs + (ofs))
 131 #define chan_write(chan, fld, v)        __raw_writel(v, (chan)->fld)
 132 #define desc_write(desc, fld, v)        __raw_writel((u32)(v), &(desc)->fld)
 133
 134 /*
 135  * Utility constructs for a cpdma descriptor pool.  Some devices (e.g. davinci
 136  * emac) have dedicated on-chip memory for these descriptors.  Some other
 137  * devices (e.g. cpsw switches) use plain old memory.  Descriptor pools
 138  * abstract out these details
 139  */
 140 static struct cpdma_desc_pool *
 141 cpdma_desc_pool_create(struct device *dev, u32 phys, u32 hw_addr,
 142                                 int size, int align)
 143 {
 144         int bitmap_size;
 145         struct cpdma_desc_pool *pool;
 146
 147         pool = kzalloc(sizeof(*pool), GFP_KERNEL);
 148         if (!pool)
 149                 return NULL;
 150
 151         spin_lock_init(&pool->lock);
 152
 153         pool->dev       = dev;
 154         pool->mem_size  = size;
 155         pool->desc_size = ALIGN(sizeof(struct cpdma_desc), align);
 156         pool->num_desc  = size / pool->desc_size;
 157
 158         bitmap_size  = (pool->num_desc / BITS_PER_LONG) * sizeof(long);
 159         pool->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
 160         if (!pool->bitmap)
 161                 goto fail;
 162
 163         if (phys) {
 164                 pool->phys  = phys;
 165                 pool->iomap = ioremap(phys, size);
 166                 pool->hw_addr = hw_addr;
 167         } else {
 168                 pool->cpumap = dma_alloc_coherent(dev, size, &pool->phys,
 169                                                   GFP_KERNEL);
 170                 pool->iomap = pool->cpumap;
 171                 pool->hw_addr = pool->phys;
 172         }
 173
 174         if (pool->iomap)
 175                 return pool;
 176
 177 fail:
 178         kfree(pool->bitmap);
 179         kfree(pool);
 180         return NULL;
 181 }
 182
 183 static void cpdma_desc_pool_destroy(struct cpdma_desc_pool *pool)
 184 {
 185         unsigned long flags;
 186
 187         if (!pool)
 188                 return;
 189
 190         spin_lock_irqsave(&pool->lock, flags);
 191         WARN_ON(pool->used_desc);
 192         kfree(pool->bitmap);
 193         if (pool->cpumap) {
 194                 dma_free_coherent(pool->dev, pool->mem_size, pool->cpumap,
 195                                   pool->phys);
 196         } else {
 197                 iounmap(pool->iomap);
 198         }
 199         spin_unlock_irqrestore(&pool->lock, flags);
 200         kfree(pool);
 201 }
 202
 203 static inline dma_addr_t desc_phys(struct cpdma_desc_pool *pool,
 204                   struct cpdma_desc __iomem *desc)
 205 {
 206         if (!desc)
 207                 return 0;
 208         return pool->hw_addr + (__force dma_addr_t)desc -
 209                             (__force dma_addr_t)pool->iomap;
 210 }
 211
 212 static inline struct cpdma_desc __iomem *
 213 desc_from_phys(struct cpdma_desc_pool *pool, dma_addr_t dma)
 214 {
 215         return dma ? pool->iomap + dma - pool->hw_addr : NULL;
 216 }
 217
 218 static struct cpdma_desc __iomem *
 219 cpdma_desc_alloc(struct cpdma_desc_pool *pool, int num_desc)
 220 {
 221         unsigned long flags;
 222         int index;
 223         struct cpdma_desc __iomem *desc = NULL;
 224
 225         spin_lock_irqsave(&pool->lock, flags);
 226
 227         index = bitmap_find_next_zero_area(pool->bitmap, pool->num_desc, 0,
 228                                            num_desc, 0);
 229         if (index < pool->num_desc) {
 230                 bitmap_set(pool->bitmap, index, num_desc);
 231                 desc = pool->iomap + pool->desc_size * index;
 232                 pool->used_desc++;
 233         }
 234
 235         spin_unlock_irqrestore(&pool->lock, flags);
 236         return desc;
 237 }
 238
 239 static void cpdma_desc_free(struct cpdma_desc_pool *pool,
 240                             struct cpdma_desc __iomem *desc, int num_desc)
 241 {
 242         unsigned long flags, index;
 243
 244         index = ((unsigned long)desc - (unsigned long)pool->iomap) /
 245                 pool->desc_size;
 246         spin_lock_irqsave(&pool->lock, flags);
 247         bitmap_clear(pool->bitmap, index, num_desc);
 248         pool->used_desc--;
 249         spin_unlock_irqrestore(&pool->lock, flags);
 250 }
 251
 252 struct cpdma_ctlr *cpdma_ctlr_create(struct cpdma_params *params)
 253 {
 254         struct cpdma_ctlr *ctlr;
 255
 256         ctlr = kzalloc(sizeof(*ctlr), GFP_KERNEL);
 257         if (!ctlr)
 258                 return NULL;
 259
 260         ctlr->state = CPDMA_STATE_IDLE;
 261         ctlr->params = *params;
 262         ctlr->dev = params->dev;
 263         spin_lock_init(&ctlr->lock);
 264
 265         ctlr->pool = cpdma_desc_pool_create(ctlr->dev,
 266                                             ctlr->params.desc_mem_phys,
 267                                             ctlr->params.desc_hw_addr,
 268                                             ctlr->params.desc_mem_size,
 269                                             ctlr->params.desc_align);
 270         if (!ctlr->pool) {
 271                 kfree(ctlr);
 272                 return NULL;
 273         }
 274
 275         if (WARN_ON(ctlr->num_chan > CPDMA_MAX_CHANNELS))
 276                 ctlr->num_chan = CPDMA_MAX_CHANNELS;
 277         return ctlr;
 278 }
 279
 280 int cpdma_ctlr_start(struct cpdma_ctlr *ctlr)
 281 {
 282         unsigned long flags;
 283         int i;
 284
 285         spin_lock_irqsave(&ctlr->lock, flags);
 286         if (ctlr->state != CPDMA_STATE_IDLE) {
 287                 spin_unlock_irqrestore(&ctlr->lock, flags);
 288                 return -EBUSY;
 289         }
 290
 291         if (ctlr->params.has_soft_reset) {
 292                 unsigned long timeout = jiffies + HZ/10;
 293
 294                 dma_reg_write(ctlr, CPDMA_SOFTRESET, 1);
 295                 while (time_before(jiffies, timeout)) {
 296                         if (dma_reg_read(ctlr, CPDMA_SOFTRESET) == 0)
 297                                 break;
 298                 }
 299                 WARN_ON(!time_before(jiffies, timeout));
 300         }
 301
 302         for (i = 0; i < ctlr->num_chan; i++) {
 303                 __raw_writel(0, ctlr->params.txhdp + 4 * i);
 304                 __raw_writel(0, ctlr->params.rxhdp + 4 * i);
 305                 __raw_writel(0, ctlr->params.txcp + 4 * i);
 306                 __raw_writel(0, ctlr->params.rxcp + 4 * i);
 307         }
 308
 309         dma_reg_write(ctlr, CPDMA_RXINTMASKCLEAR, 0xffffffff);
 310         dma_reg_write(ctlr, CPDMA_TXINTMASKCLEAR, 0xffffffff);
 311
 312         dma_reg_write(ctlr, CPDMA_TXCONTROL, 1);
 313         dma_reg_write(ctlr, CPDMA_RXCONTROL, 1);
 314
 315         ctlr->state = CPDMA_STATE_ACTIVE;
 316
 317         for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) {
 318                 if (ctlr->channels[i])
 319                         cpdma_chan_start(ctlr->channels[i]);
 320         }
 321         spin_unlock_irqrestore(&ctlr->lock, flags);
 322         return 0;
 323 }
 324
 325 int cpdma_ctlr_stop(struct cpdma_ctlr *ctlr)
 326 {
 327         unsigned long flags;
 328         int i;
 329
 330         spin_lock_irqsave(&ctlr->lock, flags);
 331         if (ctlr->state != CPDMA_STATE_ACTIVE) {
 332                 spin_unlock_irqrestore(&ctlr->lock, flags);
 333                 return -EINVAL;
 334         }
 335
 336         ctlr->state = CPDMA_STATE_TEARDOWN;
 337
 338         for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) {
 339                 if (ctlr->channels[i])
 340                         cpdma_chan_stop(ctlr->channels[i]);
 341         }
 342
 343         dma_reg_write(ctlr, CPDMA_RXINTMASKCLEAR, 0xffffffff);
 344         dma_reg_write(ctlr, CPDMA_TXINTMASKCLEAR, 0xffffffff);
 345
 346         dma_reg_write(ctlr, CPDMA_TXCONTROL, 0);
 347         dma_reg_write(ctlr, CPDMA_RXCONTROL, 0);
 348
 349         ctlr->state = CPDMA_STATE_IDLE;
 350
 351         spin_unlock_irqrestore(&ctlr->lock, flags);
 352         return 0;
 353 }
 354
 355 int cpdma_ctlr_dump(struct cpdma_ctlr *ctlr)
 356 {
 357         struct device *dev = ctlr->dev;
 358         unsigned long flags;
 359         int i;
 360
 361         spin_lock_irqsave(&ctlr->lock, flags);
 362
 363         dev_info(dev, "CPDMA: state: %s", cpdma_state_str[ctlr->state]);
 364
 365         dev_info(dev, "CPDMA: txidver: %x",
 366                  dma_reg_read(ctlr, CPDMA_TXIDVER));
 367         dev_info(dev, "CPDMA: txcontrol: %x",
 368                  dma_reg_read(ctlr, CPDMA_TXCONTROL));
 369         dev_info(dev, "CPDMA: txteardown: %x",
 370                  dma_reg_read(ctlr, CPDMA_TXTEARDOWN));
 371         dev_info(dev, "CPDMA: rxidver: %x",
 372                  dma_reg_read(ctlr, CPDMA_RXIDVER));
 373         dev_info(dev, "CPDMA: rxcontrol: %x",
 374                  dma_reg_read(ctlr, CPDMA_RXCONTROL));
 375         dev_info(dev, "CPDMA: softreset: %x",
 376                  dma_reg_read(ctlr, CPDMA_SOFTRESET));
 377         dev_info(dev, "CPDMA: rxteardown: %x",
 378                  dma_reg_read(ctlr, CPDMA_RXTEARDOWN));
 379         dev_info(dev, "CPDMA: txintstatraw: %x",
 380                  dma_reg_read(ctlr, CPDMA_TXINTSTATRAW));
 381         dev_info(dev, "CPDMA: txintstatmasked: %x",
 382                  dma_reg_read(ctlr, CPDMA_TXINTSTATMASKED));
 383         dev_info(dev, "CPDMA: txintmaskset: %x",
 384                  dma_reg_read(ctlr, CPDMA_TXINTMASKSET));
 385         dev_info(dev, "CPDMA: txintmaskclear: %x",
 386                  dma_reg_read(ctlr, CPDMA_TXINTMASKCLEAR));
 387         dev_info(dev, "CPDMA: macinvector: %x",
 388                  dma_reg_read(ctlr, CPDMA_MACINVECTOR));
 389         dev_info(dev, "CPDMA: maceoivector: %x",
 390                  dma_reg_read(ctlr, CPDMA_MACEOIVECTOR));
 391         dev_info(dev, "CPDMA: rxintstatraw: %x",
 392                  dma_reg_read(ctlr, CPDMA_RXINTSTATRAW));
 393         dev_info(dev, "CPDMA: rxintstatmasked: %x",
 394                  dma_reg_read(ctlr, CPDMA_RXINTSTATMASKED));
 395         dev_info(dev, "CPDMA: rxintmaskset: %x",
 396                  dma_reg_read(ctlr, CPDMA_RXINTMASKSET));
 397         dev_info(dev, "CPDMA: rxintmaskclear: %x",
 398                  dma_reg_read(ctlr, CPDMA_RXINTMASKCLEAR));
 399         dev_info(dev, "CPDMA: dmaintstatraw: %x",
 400                  dma_reg_read(ctlr, CPDMA_DMAINTSTATRAW));
 401         dev_info(dev, "CPDMA: dmaintstatmasked: %x",
 402                  dma_reg_read(ctlr, CPDMA_DMAINTSTATMASKED));
 403         dev_info(dev, "CPDMA: dmaintmaskset: %x",
 404                  dma_reg_read(ctlr, CPDMA_DMAINTMASKSET));
 405         dev_info(dev, "CPDMA: dmaintmaskclear: %x",
 406                  dma_reg_read(ctlr, CPDMA_DMAINTMASKCLEAR));
 407
 408         if (!ctlr->params.has_ext_regs) {
 409                 dev_info(dev, "CPDMA: dmacontrol: %x",
 410                          dma_reg_read(ctlr, CPDMA_DMACONTROL));
 411                 dev_info(dev, "CPDMA: dmastatus: %x",
 412                          dma_reg_read(ctlr, CPDMA_DMASTATUS));
 413                 dev_info(dev, "CPDMA: rxbuffofs: %x",
 414                          dma_reg_read(ctlr, CPDMA_RXBUFFOFS));
 415         }
 416
 417         for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++)
 418                 if (ctlr->channels[i])
 419                         cpdma_chan_dump(ctlr->channels[i]);
 420
 421         spin_unlock_irqrestore(&ctlr->lock, flags);
 422         return 0;
 423 }
 424
 425 int cpdma_ctlr_destroy(struct cpdma_ctlr *ctlr)
 426 {
 427         unsigned long flags;
 428         int ret = 0, i;
 429
 430         if (!ctlr)
 431                 return -EINVAL;
 432
 433         spin_lock_irqsave(&ctlr->lock, flags);
 434         if (ctlr->state != CPDMA_STATE_IDLE)
 435                 cpdma_ctlr_stop(ctlr);
 436
 437         for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) {
 438                 if (ctlr->channels[i])
 439                         cpdma_chan_destroy(ctlr->channels[i]);
 440         }
 441
 442         cpdma_desc_pool_destroy(ctlr->pool);
 443         spin_unlock_irqrestore(&ctlr->lock, flags);
 444         kfree(ctlr);
 445         return ret;
 446 }
 447
 448 int cpdma_ctlr_int_ctrl(struct cpdma_ctlr *ctlr, bool enable)
 449 {
 450         unsigned long flags;
 451         int i, reg;
 452
 453         spin_lock_irqsave(&ctlr->lock, flags);
 454         if (ctlr->state != CPDMA_STATE_ACTIVE) {
 455                 spin_unlock_irqrestore(&ctlr->lock, flags);
 456                 return -EINVAL;
 457         }
 458
 459         reg = enable ? CPDMA_DMAINTMASKSET : CPDMA_DMAINTMASKCLEAR;
 460         dma_reg_write(ctlr, reg, CPDMA_DMAINT_HOSTERR);
 461
 462         for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) {
 463                 if (ctlr->channels[i])
 464                         cpdma_chan_int_ctrl(ctlr->channels[i], enable);
 465         }
 466
 467         spin_unlock_irqrestore(&ctlr->lock, flags);
 468         return 0;
 469 }
 470
 471 void cpdma_ctlr_eoi(struct cpdma_ctlr *ctlr)
 472 {
 473         dma_reg_write(ctlr, CPDMA_MACEOIVECTOR, 0);
 474 }
 475
 476 struct cpdma_chan *cpdma_chan_create(struct cpdma_ctlr *ctlr, int chan_num,
 477                                      cpdma_handler_fn handler)
 478 {
 479         struct cpdma_chan *chan;
 480         int ret, offset = (chan_num % CPDMA_MAX_CHANNELS) * 4;
 481         unsigned long flags;
 482
 483         if (__chan_linear(chan_num) >= ctlr->num_chan)
 484                 return NULL;
 485
 486         ret = -ENOMEM;
 487         chan = kzalloc(sizeof(*chan), GFP_KERNEL);
 488         if (!chan)
 489                 goto err_chan_alloc;
 490
 491         spin_lock_irqsave(&ctlr->lock, flags);
 492         ret = -EBUSY;
 493         if (ctlr->channels[chan_num])
 494                 goto err_chan_busy;
 495
 496         chan->ctlr      = ctlr;
 497         chan->state     = CPDMA_STATE_IDLE;
 498         chan->chan_num  = chan_num;
 499         chan->handler   = handler;
 500
 501         if (is_rx_chan(chan)) {
 502                 chan->hdp       = ctlr->params.rxhdp + offset;
 503                 chan->cp        = ctlr->params.rxcp + offset;
 504                 chan->rxfree    = ctlr->params.rxfree + offset;
 505                 chan->int_set   = CPDMA_RXINTMASKSET;
 506                 chan->int_clear = CPDMA_RXINTMASKCLEAR;
 507                 chan->td        = CPDMA_RXTEARDOWN;
 508                 chan->dir       = DMA_FROM_DEVICE;
 509         } else {
 510                 chan->hdp       = ctlr->params.txhdp + offset;
 511                 chan->cp        = ctlr->params.txcp + offset;
 512                 chan->int_set   = CPDMA_TXINTMASKSET;
 513                 chan->int_clear = CPDMA_TXINTMASKCLEAR;
 514                 chan->td        = CPDMA_TXTEARDOWN;
 515                 chan->dir       = DMA_TO_DEVICE;
 516         }
 517         chan->mask = BIT(chan_linear(chan));
 518
 519         spin_lock_init(&chan->lock);
 520
 521         ctlr->channels[chan_num] = chan;
 522         spin_unlock_irqrestore(&ctlr->lock, flags);
 523         return chan;
 524
 525 err_chan_busy:
 526         spin_unlock_irqrestore(&ctlr->lock, flags);
 527         kfree(chan);
 528 err_chan_alloc:
 529         return ERR_PTR(ret);
 530 }
 531
 532 int cpdma_chan_destroy(struct cpdma_chan *chan)
 533 {
 534         struct cpdma_ctlr *ctlr = chan->ctlr;
 535         unsigned long flags;
 536
 537         if (!chan)
 538                 return -EINVAL;
 539
 540         spin_lock_irqsave(&ctlr->lock, flags);
 541         if (chan->state != CPDMA_STATE_IDLE)
 542                 cpdma_chan_stop(chan);
 543         ctlr->channels[chan->chan_num] = NULL;
 544         spin_unlock_irqrestore(&ctlr->lock, flags);
 545         kfree(chan);
 546         return 0;
 547 }
 548
 549 int cpdma_chan_get_stats(struct cpdma_chan *chan,
 550                          struct cpdma_chan_stats *stats)
 551 {
 552         unsigned long flags;
 553         if (!chan)
 554                 return -EINVAL;
 555         spin_lock_irqsave(&chan->lock, flags);
 556         memcpy(stats, &chan->stats, sizeof(*stats));
 557         spin_unlock_irqrestore(&chan->lock, flags);
 558         return 0;
 559 }
 560
 561 int cpdma_chan_dump(struct cpdma_chan *chan)
 562 {
 563         unsigned long flags;
 564         struct device *dev = chan->ctlr->dev;
 565
 566         spin_lock_irqsave(&chan->lock, flags);
 567
 568         dev_info(dev, "channel %d (%s %d) state %s",
 569                  chan->chan_num, is_rx_chan(chan) ? "rx" : "tx",
 570                  chan_linear(chan), cpdma_state_str[chan->state]);
 571         dev_info(dev, "\thdp: %x\n", chan_read(chan, hdp));
 572         dev_info(dev, "\tcp: %x\n", chan_read(chan, cp));
 573         if (chan->rxfree) {
 574                 dev_info(dev, "\trxfree: %x\n",
 575                          chan_read(chan, rxfree));
 576         }
 577
 578         dev_info(dev, "\tstats head_enqueue: %d\n",
 579                  chan->stats.head_enqueue);
 580         dev_info(dev, "\tstats tail_enqueue: %d\n",
 581                  chan->stats.tail_enqueue);
 582         dev_info(dev, "\tstats pad_enqueue: %d\n",
 583                  chan->stats.pad_enqueue);
 584         dev_info(dev, "\tstats misqueued: %d\n",
 585                  chan->stats.misqueued);
 586         dev_info(dev, "\tstats desc_alloc_fail: %d\n",
 587                  chan->stats.desc_alloc_fail);
 588         dev_info(dev, "\tstats pad_alloc_fail: %d\n",
 589                  chan->stats.pad_alloc_fail);
 590         dev_info(dev, "\tstats runt_receive_buff: %d\n",
 591                  chan->stats.runt_receive_buff);
 592         dev_info(dev, "\tstats runt_transmit_buff: %d\n",
 593                  chan->stats.runt_transmit_buff);
 594         dev_info(dev, "\tstats empty_dequeue: %d\n",
 595                  chan->stats.empty_dequeue);
 596         dev_info(dev, "\tstats busy_dequeue: %d\n",
 597                  chan->stats.busy_dequeue);
 598         dev_info(dev, "\tstats good_dequeue: %d\n",
 599                  chan->stats.good_dequeue);
 600         dev_info(dev, "\tstats requeue: %d\n",
 601                  chan->stats.requeue);
 602         dev_info(dev, "\tstats teardown_dequeue: %d\n",
 603                  chan->stats.teardown_dequeue);
 604
 605         spin_unlock_irqrestore(&chan->lock, flags);
 606         return 0;
 607 }
 608
 609 static void __cpdma_chan_submit(struct cpdma_chan *chan,
 610                                 struct cpdma_desc __iomem *desc)
 611 {
 612         struct cpdma_ctlr               *ctlr = chan->ctlr;
 613         struct cpdma_desc __iomem       *prev = chan->tail;
 614         struct cpdma_desc_pool          *pool = ctlr->pool;
 615         dma_addr_t                      desc_dma;
 616         u32                             mode;
 617
 618         desc_dma = desc_phys(pool, desc);
 619
 620         /* simple case - idle channel */
 621         if (!chan->head) {
 622                 chan->stats.head_enqueue++;
 623                 chan->head = desc;
 624                 chan->tail = desc;
 625                 if (chan->state == CPDMA_STATE_ACTIVE)
 626                         chan_write(chan, hdp, desc_dma);
 627                 return;
 628         }
 629
 630         /* first chain the descriptor at the tail of the list */
 631         desc_write(prev, hw_next, desc_dma);
 632         chan->tail = desc;
 633         chan->stats.tail_enqueue++;
 634
 635         /* next check if EOQ has been triggered already */
 636         mode = desc_read(prev, hw_mode);
 637         if (((mode & (CPDMA_DESC_EOQ | CPDMA_DESC_OWNER)) == CPDMA_DESC_EOQ) &&
 638             (chan->state == CPDMA_STATE_ACTIVE)) {
 639                 desc_write(prev, hw_mode, mode & ~CPDMA_DESC_EOQ);
 640                 chan_write(chan, hdp, desc_dma);
 641                 chan->stats.misqueued++;
 642         }
 643 }
 644
 645 int cpdma_chan_submit(struct cpdma_chan *chan, void *token, void *data,
 646                       int len, gfp_t gfp_mask)
 647 {
 648         struct cpdma_ctlr               *ctlr = chan->ctlr;
 649         struct cpdma_desc __iomem       *desc;
 650         dma_addr_t                      buffer;
 651         unsigned long                   flags;
 652         u32                             mode;
 653         int                             ret = 0;
 654
 655         spin_lock_irqsave(&chan->lock, flags);
 656
 657         if (chan->state == CPDMA_STATE_TEARDOWN) {
 658                 ret = -EINVAL;
 659                 goto unlock_ret;
 660         }
 661
 662         desc = cpdma_desc_alloc(ctlr->pool, 1);
 663         if (!desc) {
 664                 chan->stats.desc_alloc_fail++;
 665                 ret = -ENOMEM;
 666                 goto unlock_ret;
 667         }
 668
 669         if (len < ctlr->params.min_packet_size) {
 670                 len = ctlr->params.min_packet_size;
 671                 chan->stats.runt_transmit_buff++;
 672         }
 673
 674         buffer = dma_map_single(ctlr->dev, data, len, chan->dir);
 675         mode = CPDMA_DESC_OWNER | CPDMA_DESC_SOP | CPDMA_DESC_EOP;
 676
 677         desc_write(desc, hw_next,   0);
 678         desc_write(desc, hw_buffer, buffer);
 679         desc_write(desc, hw_len,    len);
 680         desc_write(desc, hw_mode,   mode | len);
 681         desc_write(desc, sw_token,  token);
 682         desc_write(desc, sw_buffer, buffer);
 683         desc_write(desc, sw_len,    len);
 684
 685         __cpdma_chan_submit(chan, desc);
 686
 687         if (chan->state == CPDMA_STATE_ACTIVE && chan->rxfree)
 688                 chan_write(chan, rxfree, 1);
 689
 690         chan->count++;
 691
 692 unlock_ret:
 693         spin_unlock_irqrestore(&chan->lock, flags);
 694         return ret;
 695 }
 696
 697 static void __cpdma_chan_free(struct cpdma_chan *chan,
 698                               struct cpdma_desc __iomem *desc,
 699                               int outlen, int status)
 700 {
 701         struct cpdma_ctlr               *ctlr = chan->ctlr;
 702         struct cpdma_desc_pool          *pool = ctlr->pool;
 703         dma_addr_t                      buff_dma;
 704         int                             origlen;
 705         void                            *token;
 706
 707         token      = (void *)desc_read(desc, sw_token);
 708         buff_dma   = desc_read(desc, sw_buffer);
 709         origlen    = desc_read(desc, sw_len);
 710
 711         dma_unmap_single(ctlr->dev, buff_dma, origlen, chan->dir);
 712         cpdma_desc_free(pool, desc, 1);
 713         (*chan->handler)(token, outlen, status);
 714 }
 715
 716 static int __cpdma_chan_process(struct cpdma_chan *chan)
 717 {
 718         struct cpdma_ctlr               *ctlr = chan->ctlr;
 719         struct cpdma_desc __iomem       *desc;
 720         int                             status, outlen;
 721         struct cpdma_desc_pool          *pool = ctlr->pool;
 722         dma_addr_t                      desc_dma;
 723         unsigned long                   flags;
 724
 725         spin_lock_irqsave(&chan->lock, flags);
 726
 727         desc = chan->head;
 728         if (!desc) {
 729                 chan->stats.empty_dequeue++;
 730                 status = -ENOENT;
 731                 goto unlock_ret;
 732         }
 733         desc_dma = desc_phys(pool, desc);
 734
 735         status  = __raw_readl(&desc->hw_mode);
 736         outlen  = status & 0x7ff;
 737         if (status & CPDMA_DESC_OWNER) {
 738                 chan->stats.busy_dequeue++;
 739                 status = -EBUSY;
 740                 goto unlock_ret;
 741         }
 742         status  = status & (CPDMA_DESC_EOQ | CPDMA_DESC_TD_COMPLETE);
 743
 744         chan->head = desc_from_phys(pool, desc_read(desc, hw_next));
 745         chan_write(chan, cp, desc_dma);
 746         chan->count--;
 747         chan->stats.good_dequeue++;
 748
 749         if (status & CPDMA_DESC_EOQ) {
 750                 chan->stats.requeue++;
 751                 chan_write(chan, hdp, desc_phys(pool, chan->head));
 752         }
 753
 754         spin_unlock_irqrestore(&chan->lock, flags);
 755
 756         __cpdma_chan_free(chan, desc, outlen, status);
 757         return status;
 758
 759 unlock_ret:
 760         spin_unlock_irqrestore(&chan->lock, flags);
 761         return status;
 762 }
 763
 764 int cpdma_chan_process(struct cpdma_chan *chan, int quota)
 765 {
 766         int used = 0, ret = 0;
 767
 768         if (chan->state != CPDMA_STATE_ACTIVE)
 769                 return -EINVAL;
 770
 771         while (used < quota) {
 772                 ret = __cpdma_chan_process(chan);
 773                 if (ret < 0)
 774                         break;
 775                 used++;
 776         }
 777         return used;
 778 }
 779
 780 int cpdma_chan_start(struct cpdma_chan *chan)
 781 {
 782         struct cpdma_ctlr       *ctlr = chan->ctlr;
 783         struct cpdma_desc_pool  *pool = ctlr->pool;
 784         unsigned long           flags;
 785
 786         spin_lock_irqsave(&chan->lock, flags);
 787         if (chan->state != CPDMA_STATE_IDLE) {
 788                 spin_unlock_irqrestore(&chan->lock, flags);
 789                 return -EBUSY;
 790         }
 791         if (ctlr->state != CPDMA_STATE_ACTIVE) {
 792                 spin_unlock_irqrestore(&chan->lock, flags);
 793                 return -EINVAL;
 794         }
 795         dma_reg_write(ctlr, chan->int_set, chan->mask);
 796         chan->state = CPDMA_STATE_ACTIVE;
 797         if (chan->head) {
 798                 chan_write(chan, hdp, desc_phys(pool, chan->head));
 799                 if (chan->rxfree)
 800                         chan_write(chan, rxfree, chan->count);
 801         }
 802
 803         spin_unlock_irqrestore(&chan->lock, flags);
 804         return 0;
 805 }
 806
 807 int cpdma_chan_stop(struct cpdma_chan *chan)
 808 {
 809         struct cpdma_ctlr       *ctlr = chan->ctlr;
 810         struct cpdma_desc_pool  *pool = ctlr->pool;
 811         unsigned long           flags;
 812         int                     ret;
 813         unsigned long           timeout;
 814
 815         spin_lock_irqsave(&chan->lock, flags);
 816         if (chan->state != CPDMA_STATE_ACTIVE) {
 817                 spin_unlock_irqrestore(&chan->lock, flags);
 818                 return -EINVAL;
 819         }
 820
 821         chan->state = CPDMA_STATE_TEARDOWN;
 822         dma_reg_write(ctlr, chan->int_clear, chan->mask);
 823
 824         /* trigger teardown */
 825         dma_reg_write(ctlr, chan->td, chan->chan_num);
 826
 827         /* wait for teardown complete */
 828         timeout = jiffies + HZ/10;      /* 100 msec */
 829         while (time_before(jiffies, timeout)) {
 830                 u32 cp = chan_read(chan, cp);
 831                 if ((cp & CPDMA_TEARDOWN_VALUE) == CPDMA_TEARDOWN_VALUE)
 832                         break;
 833                 cpu_relax();
 834         }
 835         WARN_ON(!time_before(jiffies, timeout));
 836         chan_write(chan, cp, CPDMA_TEARDOWN_VALUE);
 837
 838         /* handle completed packets */
 839         do {
 840                 ret = __cpdma_chan_process(chan);
 841                 if (ret < 0)
 842                         break;
 843         } while ((ret & CPDMA_DESC_TD_COMPLETE) == 0);
 844
 845         /* remaining packets haven't been tx/rx'ed, clean them up */
 846         while (chan->head) {
 847                 struct cpdma_desc __iomem *desc = chan->head;
 848                 dma_addr_t next_dma;
 849
 850                 next_dma = desc_read(desc, hw_next);
 851                 chan->head = desc_from_phys(pool, next_dma);
 852                 chan->stats.teardown_dequeue++;
 853
 854                 /* issue callback without locks held */
 855                 spin_unlock_irqrestore(&chan->lock, flags);
 856                 __cpdma_chan_free(chan, desc, 0, -ENOSYS);
 857                 spin_lock_irqsave(&chan->lock, flags);
 858         }
 859
 860         chan->state = CPDMA_STATE_IDLE;
 861         spin_unlock_irqrestore(&chan->lock, flags);
 862         return 0;
 863 }
 864
 865 int cpdma_chan_int_ctrl(struct cpdma_chan *chan, bool enable)
 866 {
 867         unsigned long flags;
 868
 869         spin_lock_irqsave(&chan->lock, flags);
 870         if (chan->state != CPDMA_STATE_ACTIVE) {
 871                 spin_unlock_irqrestore(&chan->lock, flags);
 872                 return -EINVAL;
 873         }
 874
 875         dma_reg_write(chan->ctlr, enable ? chan->int_set : chan->int_clear,
 876                       chan->mask);
 877         spin_unlock_irqrestore(&chan->lock, flags);
 878
 879         return 0;
 880 }
 881
 882 struct cpdma_control_info {
 883         u32             reg;
 884         u32             shift, mask;
 885         int             access;
 886 #define ACCESS_RO       BIT(0)
 887 #define ACCESS_WO       BIT(1)
 888 #define ACCESS_RW       (ACCESS_RO | ACCESS_WO)
 889 };
 890
 891 struct cpdma_control_info controls[] = {
 892         [CPDMA_CMD_IDLE]          = {CPDMA_DMACONTROL,  3,  1,      ACCESS_WO},
 893         [CPDMA_COPY_ERROR_FRAMES] = {CPDMA_DMACONTROL,  4,  1,      ACCESS_RW},
 894         [CPDMA_RX_OFF_LEN_UPDATE] = {CPDMA_DMACONTROL,  2,  1,      ACCESS_RW},
 895         [CPDMA_RX_OWNERSHIP_FLIP] = {CPDMA_DMACONTROL,  1,  1,      ACCESS_RW},
 896         [CPDMA_TX_PRIO_FIXED]     = {CPDMA_DMACONTROL,  0,  1,      ACCESS_RW},
 897         [CPDMA_STAT_IDLE]         = {CPDMA_DMASTATUS,   31, 1,      ACCESS_RO},
 898         [CPDMA_STAT_TX_ERR_CODE]  = {CPDMA_DMASTATUS,   20, 0xf,    ACCESS_RW},
 899         [CPDMA_STAT_TX_ERR_CHAN]  = {CPDMA_DMASTATUS,   16, 0x7,    ACCESS_RW},
 900         [CPDMA_STAT_RX_ERR_CODE]  = {CPDMA_DMASTATUS,   12, 0xf,    ACCESS_RW},
 901         [CPDMA_STAT_RX_ERR_CHAN]  = {CPDMA_DMASTATUS,   8,  0x7,    ACCESS_RW},
 902         [CPDMA_RX_BUFFER_OFFSET]  = {CPDMA_RXBUFFOFS,   0,  0xffff, ACCESS_RW},
 903 };
 904
 905 int cpdma_control_get(struct cpdma_ctlr *ctlr, int control)
 906 {
 907         unsigned long flags;
 908         struct cpdma_control_info *info = &controls[control];
 909         int ret;
 910
 911         spin_lock_irqsave(&ctlr->lock, flags);
 912
 913         ret = -ENOTSUPP;
 914         if (!ctlr->params.has_ext_regs)
 915                 goto unlock_ret;
 916
 917         ret = -EINVAL;
 918         if (ctlr->state != CPDMA_STATE_ACTIVE)
 919                 goto unlock_ret;
 920
 921         ret = -ENOENT;
 922         if (control < 0 || control >= ARRAY_SIZE(controls))
 923                 goto unlock_ret;
 924
 925         ret = -EPERM;
 926         if ((info->access & ACCESS_RO) != ACCESS_RO)
 927                 goto unlock_ret;
 928
 929         ret = (dma_reg_read(ctlr, info->reg) >> info->shift) & info->mask;
 930
 931 unlock_ret:
 932         spin_unlock_irqrestore(&ctlr->lock, flags);
 933         return ret;
 934 }
 935
 936 int cpdma_control_set(struct cpdma_ctlr *ctlr, int control, int value)
 937 {
 938         unsigned long flags;
 939         struct cpdma_control_info *info = &controls[control];
 940         int ret;
 941         u32 val;
 942
 943         spin_lock_irqsave(&ctlr->lock, flags);
 944
 945         ret = -ENOTSUPP;
 946         if (!ctlr->params.has_ext_regs)
 947                 goto unlock_ret;
 948
 949         ret = -EINVAL;
 950         if (ctlr->state != CPDMA_STATE_ACTIVE)
 951                 goto unlock_ret;
 952
 953         ret = -ENOENT;
 954         if (control < 0 || control >= ARRAY_SIZE(controls))
 955                 goto unlock_ret;
 956
 957         ret = -EPERM;
 958         if ((info->access & ACCESS_WO) != ACCESS_WO)
 959                 goto unlock_ret;
 960
 961         val  = dma_reg_read(ctlr, info->reg);
 962         val &= ~(info->mask << info->shift);
 963         val |= (value & info->mask) << info->shift;
 964         dma_reg_write(ctlr, info->reg, val);
 965         ret = 0;
 966
 967 unlock_ret:
 968         spin_unlock_irqrestore(&ctlr->lock, flags);
 969         return ret;
 970 }