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/module.h>
  19 #include <linux/slab.h>
  20 #include <linux/err.h>
  21 #include <linux/dma-mapping.h>
  22 #include <linux/io.h>
  23 #include <linux/delay.h>
  24
  25 #include "davinci_cpdma.h"
  26
  27 /* DMA Registers */
  28 #define CPDMA_TXIDVER           0x00
  29 #define CPDMA_TXCONTROL         0x04
  30 #define CPDMA_TXTEARDOWN        0x08
  31 #define CPDMA_RXIDVER           0x10
  32 #define CPDMA_RXCONTROL         0x14
  33 #define CPDMA_SOFTRESET         0x1c
  34 #define CPDMA_RXTEARDOWN        0x18
  35 #define CPDMA_TXINTSTATRAW      0x80
  36 #define CPDMA_TXINTSTATMASKED   0x84
  37 #define CPDMA_TXINTMASKSET      0x88
  38 #define CPDMA_TXINTMASKCLEAR    0x8c
  39 #define CPDMA_MACINVECTOR       0x90
  40 #define CPDMA_MACEOIVECTOR      0x94
  41 #define CPDMA_RXINTSTATRAW      0xa0
  42 #define CPDMA_RXINTSTATMASKED   0xa4
  43 #define CPDMA_RXINTMASKSET      0xa8
  44 #define CPDMA_RXINTMASKCLEAR    0xac
  45 #define CPDMA_DMAINTSTATRAW     0xb0
  46 #define CPDMA_DMAINTSTATMASKED  0xb4
  47 #define CPDMA_DMAINTMASKSET     0xb8
  48 #define CPDMA_DMAINTMASKCLEAR   0xbc
  49 #define CPDMA_DMAINT_HOSTERR    BIT(1)
  50
  51 /* the following exist only if has_ext_regs is set */
  52 #define CPDMA_DMACONTROL        0x20
  53 #define CPDMA_DMASTATUS         0x24
  54 #define CPDMA_RXBUFFOFS         0x28
  55 #define CPDMA_EM_CONTROL        0x2c
  56
  57 /* Descriptor mode bits */
  58 #define CPDMA_DESC_SOP          BIT(31)
  59 #define CPDMA_DESC_EOP          BIT(30)
  60 #define CPDMA_DESC_OWNER        BIT(29)
  61 #define CPDMA_DESC_EOQ          BIT(28)
  62 #define CPDMA_DESC_TD_COMPLETE  BIT(27)
  63 #define CPDMA_DESC_PASS_CRC     BIT(26)
  64 #define CPDMA_DESC_TO_PORT_EN   BIT(20)
  65 #define CPDMA_TO_PORT_SHIFT     16
  66 #define CPDMA_DESC_PORT_MASK    (BIT(18) | BIT(17) | BIT(16))
  67 #define CPDMA_DESC_CRC_LEN      4
  68
  69 #define CPDMA_TEARDOWN_VALUE    0xfffffffc
  70
  71 struct cpdma_desc {
  72         /* hardware fields */
  73         u32                     hw_next;
  74         u32                     hw_buffer;
  75         u32                     hw_len;
  76         u32                     hw_mode;
  77         /* software fields */
  78         void                    *sw_token;
  79         u32                     sw_buffer;
  80         u32                     sw_len;
  81 };
  82
  83 struct cpdma_desc_pool {
  84         u32                     phys;
  85         u32                     hw_addr;
  86         void __iomem            *iomap;         /* ioremap map */
  87         void                    *cpumap;        /* dma_alloc map */
  88         int                     desc_size, mem_size;
  89         int                     num_desc, used_desc;
  90         unsigned long           *bitmap;
  91         struct device           *dev;
  92         spinlock_t              lock;
  93 };
  94
  95 enum cpdma_state {
  96         CPDMA_STATE_IDLE,
  97         CPDMA_STATE_ACTIVE,
  98         CPDMA_STATE_TEARDOWN,
  99 };
 100
 101 static const char *cpdma_state_str[] = { "idle", "active", "teardown" };
 102
 103 struct cpdma_ctlr {
 104         enum cpdma_state        state;
 105         struct cpdma_params     params;
 106         struct device           *dev;
 107         struct cpdma_desc_pool  *pool;
 108         spinlock_t              lock;
 109         struct cpdma_chan       *channels[2 * CPDMA_MAX_CHANNELS];
 110 };
 111
 112 struct cpdma_chan {
 113         struct cpdma_desc __iomem       *head, *tail;
 114         void __iomem                    *hdp, *cp, *rxfree;
 115         enum cpdma_state                state;
 116         struct cpdma_ctlr               *ctlr;
 117         int                             chan_num;
 118         spinlock_t                      lock;
 119         int                             count;
 120         u32                             mask;
 121         cpdma_handler_fn                handler;
 122         enum dma_data_direction         dir;
 123         struct cpdma_chan_stats         stats;
 124         /* offsets into dmaregs */
 125         int     int_set, int_clear, td;
 126 };
 127
 128 /* The following make access to common cpdma_ctlr params more readable */
 129 #define dmaregs         params.dmaregs
 130 #define num_chan        params.num_chan
 131
 132 /* various accessors */
 133 #define dma_reg_read(ctlr, ofs)         __raw_readl((ctlr)->dmaregs + (ofs))
 134 #define chan_read(chan, fld)            __raw_readl((chan)->fld)
 135 #define desc_read(desc, fld)            __raw_readl(&(desc)->fld)
 136 #define dma_reg_write(ctlr, ofs, v)     __raw_writel(v, (ctlr)->dmaregs + (ofs))
 137 #define chan_write(chan, fld, v)        __raw_writel(v, (chan)->fld)
 138 #define desc_write(desc, fld, v)        __raw_writel((u32)(v), &(desc)->fld)
 139
 140 #define cpdma_desc_to_port(chan, mode, directed)                        \
 141         do {                                                            \
 142                 if (!is_rx_chan(chan) && ((directed == 1) ||            \
 143                                           (directed == 2)))             \
 144                         mode |= (CPDMA_DESC_TO_PORT_EN |                \
 145                                  (directed << CPDMA_TO_PORT_SHIFT));    \
 146         } while (0)
 147
 148 /*
 149  * Utility constructs for a cpdma descriptor pool.  Some devices (e.g. davinci
 150  * emac) have dedicated on-chip memory for these descriptors.  Some other
 151  * devices (e.g. cpsw switches) use plain old memory.  Descriptor pools
 152  * abstract out these details
 153  */
 154 static struct cpdma_desc_pool *
 155 cpdma_desc_pool_create(struct device *dev, u32 phys, u32 hw_addr,
 156                                 int size, int align)
 157 {
 158         int bitmap_size;
 159         struct cpdma_desc_pool *pool;
 160
 161         pool = kzalloc(sizeof(*pool), GFP_KERNEL);
 162         if (!pool)
 163                 return NULL;
 164
 165         spin_lock_init(&pool->lock);
 166
 167         pool->dev       = dev;
 168         pool->mem_size  = size;
 169         pool->desc_size = ALIGN(sizeof(struct cpdma_desc), align);
 170         pool->num_desc  = size / pool->desc_size;
 171
 172         bitmap_size  = (pool->num_desc / BITS_PER_LONG) * sizeof(long);
 173         pool->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
 174         if (!pool->bitmap)
 175                 goto fail;
 176
 177         if (phys) {
 178                 pool->phys  = phys;
 179                 pool->iomap = ioremap(phys, size);
 180                 pool->hw_addr = hw_addr;
 181         } else {
 182                 pool->cpumap = dma_alloc_coherent(dev, size, &pool->phys,
 183                                                   GFP_KERNEL);
 184                 pool->iomap = pool->cpumap;
 185                 pool->hw_addr = pool->phys;
 186         }
 187
 188         if (pool->iomap)
 189                 return pool;
 190
 191 fail:
 192         kfree(pool->bitmap);
 193         kfree(pool);
 194         return NULL;
 195 }
 196
 197 static void cpdma_desc_pool_destroy(struct cpdma_desc_pool *pool)
 198 {
 199         unsigned long flags;
 200
 201         if (!pool)
 202                 return;
 203
 204         spin_lock_irqsave(&pool->lock, flags);
 205         WARN_ON(pool->used_desc);
 206         kfree(pool->bitmap);
 207         if (pool->cpumap) {
 208                 dma_free_coherent(pool->dev, pool->mem_size, pool->cpumap,
 209                                   pool->phys);
 210         } else {
 211                 iounmap(pool->iomap);
 212         }
 213         spin_unlock_irqrestore(&pool->lock, flags);
 214         kfree(pool);
 215 }
 216
 217 static inline dma_addr_t desc_phys(struct cpdma_desc_pool *pool,
 218                   struct cpdma_desc __iomem *desc)
 219 {
 220         if (!desc)
 221                 return 0;
 222         return pool->hw_addr + (__force dma_addr_t)desc -
 223                             (__force dma_addr_t)pool->iomap;
 224 }
 225
 226 static inline struct cpdma_desc __iomem *
 227 desc_from_phys(struct cpdma_desc_pool *pool, dma_addr_t dma)
 228 {
 229         return dma ? pool->iomap + dma - pool->hw_addr : NULL;
 230 }
 231
 232 static struct cpdma_desc __iomem *
 233 cpdma_desc_alloc(struct cpdma_desc_pool *pool, int num_desc, bool is_rx)
 234 {
 235         unsigned long flags;
 236         int index;
 237         int desc_start;
 238         int desc_end;
 239         struct cpdma_desc __iomem *desc = NULL;
 240
 241         spin_lock_irqsave(&pool->lock, flags);
 242
 243         if (is_rx) {
 244                 desc_start = 0;
 245                 desc_end = pool->num_desc/2;
 246          } else {
 247                 desc_start = pool->num_desc/2;
 248                 desc_end = pool->num_desc;
 249         }
 250
 251         index = bitmap_find_next_zero_area(pool->bitmap,
 252                                 desc_end, desc_start, num_desc, 0);
 253         if (index < desc_end) {
 254                 bitmap_set(pool->bitmap, index, num_desc);
 255                 desc = pool->iomap + pool->desc_size * index;
 256                 pool->used_desc++;
 257         }
 258
 259         spin_unlock_irqrestore(&pool->lock, flags);
 260         return desc;
 261 }
 262
 263 static void cpdma_desc_free(struct cpdma_desc_pool *pool,
 264                             struct cpdma_desc __iomem *desc, int num_desc)
 265 {
 266         unsigned long flags, index;
 267
 268         index = ((unsigned long)desc - (unsigned long)pool->iomap) /
 269                 pool->desc_size;
 270         spin_lock_irqsave(&pool->lock, flags);
 271         bitmap_clear(pool->bitmap, index, num_desc);
 272         pool->used_desc--;
 273         spin_unlock_irqrestore(&pool->lock, flags);
 274 }
 275
 276 struct cpdma_ctlr *cpdma_ctlr_create(struct cpdma_params *params)
 277 {
 278         struct cpdma_ctlr *ctlr;
 279
 280         ctlr = kzalloc(sizeof(*ctlr), GFP_KERNEL);
 281         if (!ctlr)
 282                 return NULL;
 283
 284         ctlr->state = CPDMA_STATE_IDLE;
 285         ctlr->params = *params;
 286         ctlr->dev = params->dev;
 287         spin_lock_init(&ctlr->lock);
 288
 289         ctlr->pool = cpdma_desc_pool_create(ctlr->dev,
 290                                             ctlr->params.desc_mem_phys,
 291                                             ctlr->params.desc_hw_addr,
 292                                             ctlr->params.desc_mem_size,
 293                                             ctlr->params.desc_align);
 294         if (!ctlr->pool) {
 295                 kfree(ctlr);
 296                 return NULL;
 297         }
 298
 299         if (WARN_ON(ctlr->num_chan > CPDMA_MAX_CHANNELS))
 300                 ctlr->num_chan = CPDMA_MAX_CHANNELS;
 301         return ctlr;
 302 }
 303 EXPORT_SYMBOL_GPL(cpdma_ctlr_create);
 304
 305 int cpdma_ctlr_start(struct cpdma_ctlr *ctlr)
 306 {
 307         unsigned long flags;
 308         int i;
 309
 310         spin_lock_irqsave(&ctlr->lock, flags);
 311         if (ctlr->state != CPDMA_STATE_IDLE) {
 312                 spin_unlock_irqrestore(&ctlr->lock, flags);
 313                 return -EBUSY;
 314         }
 315
 316         if (ctlr->params.has_soft_reset) {
 317                 unsigned timeout = 10 * 100;
 318
 319                 dma_reg_write(ctlr, CPDMA_SOFTRESET, 1);
 320                 while (timeout) {
 321                         if (dma_reg_read(ctlr, CPDMA_SOFTRESET) == 0)
 322                                 break;
 323                         udelay(10);
 324                         timeout--;
 325                 }
 326                 WARN_ON(!timeout);
 327         }
 328
 329         for (i = 0; i < ctlr->num_chan; i++) {
 330                 __raw_writel(0, ctlr->params.txhdp + 4 * i);
 331                 __raw_writel(0, ctlr->params.rxhdp + 4 * i);
 332                 __raw_writel(0, ctlr->params.txcp + 4 * i);
 333                 __raw_writel(0, ctlr->params.rxcp + 4 * i);
 334         }
 335
 336         dma_reg_write(ctlr, CPDMA_RXINTMASKCLEAR, 0xffffffff);
 337         dma_reg_write(ctlr, CPDMA_TXINTMASKCLEAR, 0xffffffff);
 338
 339         dma_reg_write(ctlr, CPDMA_TXCONTROL, 1);
 340         dma_reg_write(ctlr, CPDMA_RXCONTROL, 1);
 341
 342         ctlr->state = CPDMA_STATE_ACTIVE;
 343
 344         for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) {
 345                 if (ctlr->channels[i])
 346                         cpdma_chan_start(ctlr->channels[i]);
 347         }
 348         spin_unlock_irqrestore(&ctlr->lock, flags);
 349         return 0;
 350 }
 351 EXPORT_SYMBOL_GPL(cpdma_ctlr_start);
 352
 353 int cpdma_ctlr_stop(struct cpdma_ctlr *ctlr)
 354 {
 355         unsigned long flags;
 356         int i;
 357
 358         spin_lock_irqsave(&ctlr->lock, flags);
 359         if (ctlr->state != CPDMA_STATE_ACTIVE) {
 360                 spin_unlock_irqrestore(&ctlr->lock, flags);
 361                 return -EINVAL;
 362         }
 363
 364         ctlr->state = CPDMA_STATE_TEARDOWN;
 365
 366         for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) {
 367                 if (ctlr->channels[i])
 368                         cpdma_chan_stop(ctlr->channels[i]);
 369         }
 370
 371         dma_reg_write(ctlr, CPDMA_RXINTMASKCLEAR, 0xffffffff);
 372         dma_reg_write(ctlr, CPDMA_TXINTMASKCLEAR, 0xffffffff);
 373
 374         dma_reg_write(ctlr, CPDMA_TXCONTROL, 0);
 375         dma_reg_write(ctlr, CPDMA_RXCONTROL, 0);
 376
 377         ctlr->state = CPDMA_STATE_IDLE;
 378
 379         spin_unlock_irqrestore(&ctlr->lock, flags);
 380         return 0;
 381 }
 382 EXPORT_SYMBOL_GPL(cpdma_ctlr_stop);
 383
 384 int cpdma_ctlr_dump(struct cpdma_ctlr *ctlr)
 385 {
 386         struct device *dev = ctlr->dev;
 387         unsigned long flags;
 388         int i;
 389
 390         spin_lock_irqsave(&ctlr->lock, flags);
 391
 392         dev_info(dev, "CPDMA: state: %s", cpdma_state_str[ctlr->state]);
 393
 394         dev_info(dev, "CPDMA: txidver: %x",
 395                  dma_reg_read(ctlr, CPDMA_TXIDVER));
 396         dev_info(dev, "CPDMA: txcontrol: %x",
 397                  dma_reg_read(ctlr, CPDMA_TXCONTROL));
 398         dev_info(dev, "CPDMA: txteardown: %x",
 399                  dma_reg_read(ctlr, CPDMA_TXTEARDOWN));
 400         dev_info(dev, "CPDMA: rxidver: %x",
 401                  dma_reg_read(ctlr, CPDMA_RXIDVER));
 402         dev_info(dev, "CPDMA: rxcontrol: %x",
 403                  dma_reg_read(ctlr, CPDMA_RXCONTROL));
 404         dev_info(dev, "CPDMA: softreset: %x",
 405                  dma_reg_read(ctlr, CPDMA_SOFTRESET));
 406         dev_info(dev, "CPDMA: rxteardown: %x",
 407                  dma_reg_read(ctlr, CPDMA_RXTEARDOWN));
 408         dev_info(dev, "CPDMA: txintstatraw: %x",
 409                  dma_reg_read(ctlr, CPDMA_TXINTSTATRAW));
 410         dev_info(dev, "CPDMA: txintstatmasked: %x",
 411                  dma_reg_read(ctlr, CPDMA_TXINTSTATMASKED));
 412         dev_info(dev, "CPDMA: txintmaskset: %x",
 413                  dma_reg_read(ctlr, CPDMA_TXINTMASKSET));
 414         dev_info(dev, "CPDMA: txintmaskclear: %x",
 415                  dma_reg_read(ctlr, CPDMA_TXINTMASKCLEAR));
 416         dev_info(dev, "CPDMA: macinvector: %x",
 417                  dma_reg_read(ctlr, CPDMA_MACINVECTOR));
 418         dev_info(dev, "CPDMA: maceoivector: %x",
 419                  dma_reg_read(ctlr, CPDMA_MACEOIVECTOR));
 420         dev_info(dev, "CPDMA: rxintstatraw: %x",
 421                  dma_reg_read(ctlr, CPDMA_RXINTSTATRAW));
 422         dev_info(dev, "CPDMA: rxintstatmasked: %x",
 423                  dma_reg_read(ctlr, CPDMA_RXINTSTATMASKED));
 424         dev_info(dev, "CPDMA: rxintmaskset: %x",
 425                  dma_reg_read(ctlr, CPDMA_RXINTMASKSET));
 426         dev_info(dev, "CPDMA: rxintmaskclear: %x",
 427                  dma_reg_read(ctlr, CPDMA_RXINTMASKCLEAR));
 428         dev_info(dev, "CPDMA: dmaintstatraw: %x",
 429                  dma_reg_read(ctlr, CPDMA_DMAINTSTATRAW));
 430         dev_info(dev, "CPDMA: dmaintstatmasked: %x",
 431                  dma_reg_read(ctlr, CPDMA_DMAINTSTATMASKED));
 432         dev_info(dev, "CPDMA: dmaintmaskset: %x",
 433                  dma_reg_read(ctlr, CPDMA_DMAINTMASKSET));
 434         dev_info(dev, "CPDMA: dmaintmaskclear: %x",
 435                  dma_reg_read(ctlr, CPDMA_DMAINTMASKCLEAR));
 436
 437         if (!ctlr->params.has_ext_regs) {
 438                 dev_info(dev, "CPDMA: dmacontrol: %x",
 439                          dma_reg_read(ctlr, CPDMA_DMACONTROL));
 440                 dev_info(dev, "CPDMA: dmastatus: %x",
 441                          dma_reg_read(ctlr, CPDMA_DMASTATUS));
 442                 dev_info(dev, "CPDMA: rxbuffofs: %x",
 443                          dma_reg_read(ctlr, CPDMA_RXBUFFOFS));
 444         }
 445
 446         for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++)
 447                 if (ctlr->channels[i])
 448                         cpdma_chan_dump(ctlr->channels[i]);
 449
 450         spin_unlock_irqrestore(&ctlr->lock, flags);
 451         return 0;
 452 }
 453 EXPORT_SYMBOL_GPL(cpdma_ctlr_dump);
 454
 455 int cpdma_ctlr_destroy(struct cpdma_ctlr *ctlr)
 456 {
 457         unsigned long flags;
 458         int ret = 0, i;
 459
 460         if (!ctlr)
 461                 return -EINVAL;
 462
 463         spin_lock_irqsave(&ctlr->lock, flags);
 464         if (ctlr->state != CPDMA_STATE_IDLE)
 465                 cpdma_ctlr_stop(ctlr);
 466
 467         for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++)
 468                 cpdma_chan_destroy(ctlr->channels[i]);
 469
 470         cpdma_desc_pool_destroy(ctlr->pool);
 471         spin_unlock_irqrestore(&ctlr->lock, flags);
 472         kfree(ctlr);
 473         return ret;
 474 }
 475 EXPORT_SYMBOL_GPL(cpdma_ctlr_destroy);
 476
 477 int cpdma_ctlr_int_ctrl(struct cpdma_ctlr *ctlr, bool enable)
 478 {
 479         unsigned long flags;
 480         int i, reg;
 481
 482         spin_lock_irqsave(&ctlr->lock, flags);
 483         if (ctlr->state != CPDMA_STATE_ACTIVE) {
 484                 spin_unlock_irqrestore(&ctlr->lock, flags);
 485                 return -EINVAL;
 486         }
 487
 488         reg = enable ? CPDMA_DMAINTMASKSET : CPDMA_DMAINTMASKCLEAR;
 489         dma_reg_write(ctlr, reg, CPDMA_DMAINT_HOSTERR);
 490
 491         for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) {
 492                 if (ctlr->channels[i])
 493                         cpdma_chan_int_ctrl(ctlr->channels[i], enable);
 494         }
 495
 496         spin_unlock_irqrestore(&ctlr->lock, flags);
 497         return 0;
 498 }
 499 EXPORT_SYMBOL_GPL(cpdma_ctlr_int_ctrl);
 500
 501 void cpdma_ctlr_eoi(struct cpdma_ctlr *ctlr, u32 value)
 502 {
 503         dma_reg_write(ctlr, CPDMA_MACEOIVECTOR, value);
 504 }
 505 EXPORT_SYMBOL_GPL(cpdma_ctlr_eoi);
 506
 507 struct cpdma_chan *cpdma_chan_create(struct cpdma_ctlr *ctlr, int chan_num,
 508                                      cpdma_handler_fn handler)
 509 {
 510         struct cpdma_chan *chan;
 511         int ret, offset = (chan_num % CPDMA_MAX_CHANNELS) * 4;
 512         unsigned long flags;
 513
 514         if (__chan_linear(chan_num) >= ctlr->num_chan)
 515                 return NULL;
 516
 517         ret = -ENOMEM;
 518         chan = kzalloc(sizeof(*chan), GFP_KERNEL);
 519         if (!chan)
 520                 goto err_chan_alloc;
 521
 522         spin_lock_irqsave(&ctlr->lock, flags);
 523         ret = -EBUSY;
 524         if (ctlr->channels[chan_num])
 525                 goto err_chan_busy;
 526
 527         chan->ctlr      = ctlr;
 528         chan->state     = CPDMA_STATE_IDLE;
 529         chan->chan_num  = chan_num;
 530         chan->handler   = handler;
 531
 532         if (is_rx_chan(chan)) {
 533                 chan->hdp       = ctlr->params.rxhdp + offset;
 534                 chan->cp        = ctlr->params.rxcp + offset;
 535                 chan->rxfree    = ctlr->params.rxfree + offset;
 536                 chan->int_set   = CPDMA_RXINTMASKSET;
 537                 chan->int_clear = CPDMA_RXINTMASKCLEAR;
 538                 chan->td        = CPDMA_RXTEARDOWN;
 539                 chan->dir       = DMA_FROM_DEVICE;
 540         } else {
 541                 chan->hdp       = ctlr->params.txhdp + offset;
 542                 chan->cp        = ctlr->params.txcp + offset;
 543                 chan->int_set   = CPDMA_TXINTMASKSET;
 544                 chan->int_clear = CPDMA_TXINTMASKCLEAR;
 545                 chan->td        = CPDMA_TXTEARDOWN;
 546                 chan->dir       = DMA_TO_DEVICE;
 547         }
 548         chan->mask = BIT(chan_linear(chan));
 549
 550         spin_lock_init(&chan->lock);
 551
 552         ctlr->channels[chan_num] = chan;
 553         spin_unlock_irqrestore(&ctlr->lock, flags);
 554         return chan;
 555
 556 err_chan_busy:
 557         spin_unlock_irqrestore(&ctlr->lock, flags);
 558         kfree(chan);
 559 err_chan_alloc:
 560         return ERR_PTR(ret);
 561 }
 562 EXPORT_SYMBOL_GPL(cpdma_chan_create);
 563
 564 int cpdma_chan_destroy(struct cpdma_chan *chan)
 565 {
 566         struct cpdma_ctlr *ctlr;
 567         unsigned long flags;
 568
 569         if (!chan)
 570                 return -EINVAL;
 571         ctlr = chan->ctlr;
 572
 573         spin_lock_irqsave(&ctlr->lock, flags);
 574         if (chan->state != CPDMA_STATE_IDLE)
 575                 cpdma_chan_stop(chan);
 576         ctlr->channels[chan->chan_num] = NULL;
 577         spin_unlock_irqrestore(&ctlr->lock, flags);
 578         kfree(chan);
 579         return 0;
 580 }
 581 EXPORT_SYMBOL_GPL(cpdma_chan_destroy);
 582
 583 int cpdma_chan_get_stats(struct cpdma_chan *chan,
 584                          struct cpdma_chan_stats *stats)
 585 {
 586         unsigned long flags;
 587         if (!chan)
 588                 return -EINVAL;
 589         spin_lock_irqsave(&chan->lock, flags);
 590         memcpy(stats, &chan->stats, sizeof(*stats));
 591         spin_unlock_irqrestore(&chan->lock, flags);
 592         return 0;
 593 }
 594 EXPORT_SYMBOL_GPL(cpdma_chan_get_stats);
 595
 596 int cpdma_chan_dump(struct cpdma_chan *chan)
 597 {
 598         unsigned long flags;
 599         struct device *dev = chan->ctlr->dev;
 600
 601         spin_lock_irqsave(&chan->lock, flags);
 602
 603         dev_info(dev, "channel %d (%s %d) state %s",
 604                  chan->chan_num, is_rx_chan(chan) ? "rx" : "tx",
 605                  chan_linear(chan), cpdma_state_str[chan->state]);
 606         dev_info(dev, "\thdp: %x\n", chan_read(chan, hdp));
 607         dev_info(dev, "\tcp: %x\n", chan_read(chan, cp));
 608         if (chan->rxfree) {
 609                 dev_info(dev, "\trxfree: %x\n",
 610                          chan_read(chan, rxfree));
 611         }
 612
 613         dev_info(dev, "\tstats head_enqueue: %d\n",
 614                  chan->stats.head_enqueue);
 615         dev_info(dev, "\tstats tail_enqueue: %d\n",
 616                  chan->stats.tail_enqueue);
 617         dev_info(dev, "\tstats pad_enqueue: %d\n",
 618                  chan->stats.pad_enqueue);
 619         dev_info(dev, "\tstats misqueued: %d\n",
 620                  chan->stats.misqueued);
 621         dev_info(dev, "\tstats desc_alloc_fail: %d\n",
 622                  chan->stats.desc_alloc_fail);
 623         dev_info(dev, "\tstats pad_alloc_fail: %d\n",
 624                  chan->stats.pad_alloc_fail);
 625         dev_info(dev, "\tstats runt_receive_buff: %d\n",
 626                  chan->stats.runt_receive_buff);
 627         dev_info(dev, "\tstats runt_transmit_buff: %d\n",
 628                  chan->stats.runt_transmit_buff);
 629         dev_info(dev, "\tstats empty_dequeue: %d\n",
 630                  chan->stats.empty_dequeue);
 631         dev_info(dev, "\tstats busy_dequeue: %d\n",
 632                  chan->stats.busy_dequeue);
 633         dev_info(dev, "\tstats good_dequeue: %d\n",
 634                  chan->stats.good_dequeue);
 635         dev_info(dev, "\tstats requeue: %d\n",
 636                  chan->stats.requeue);
 637         dev_info(dev, "\tstats teardown_dequeue: %d\n",
 638                  chan->stats.teardown_dequeue);
 639
 640         spin_unlock_irqrestore(&chan->lock, flags);
 641         return 0;
 642 }
 643
 644 static void __cpdma_chan_submit(struct cpdma_chan *chan,
 645                                 struct cpdma_desc __iomem *desc)
 646 {
 647         struct cpdma_ctlr               *ctlr = chan->ctlr;
 648         struct cpdma_desc __iomem       *prev = chan->tail;
 649         struct cpdma_desc_pool          *pool = ctlr->pool;
 650         dma_addr_t                      desc_dma;
 651         u32                             mode;
 652
 653         desc_dma = desc_phys(pool, desc);
 654
 655         /* simple case - idle channel */
 656         if (!chan->head) {
 657                 chan->stats.head_enqueue++;
 658                 chan->head = desc;
 659                 chan->tail = desc;
 660                 if (chan->state == CPDMA_STATE_ACTIVE)
 661                         chan_write(chan, hdp, desc_dma);
 662                 return;
 663         }
 664
 665         /* first chain the descriptor at the tail of the list */
 666         desc_write(prev, hw_next, desc_dma);
 667         chan->tail = desc;
 668         chan->stats.tail_enqueue++;
 669
 670         /* next check if EOQ has been triggered already */
 671         mode = desc_read(prev, hw_mode);
 672         if (((mode & (CPDMA_DESC_EOQ | CPDMA_DESC_OWNER)) == CPDMA_DESC_EOQ) &&
 673             (chan->state == CPDMA_STATE_ACTIVE)) {
 674                 desc_write(prev, hw_mode, mode & ~CPDMA_DESC_EOQ);
 675                 chan_write(chan, hdp, desc_dma);
 676                 chan->stats.misqueued++;
 677         }
 678 }
 679
 680 int cpdma_chan_submit(struct cpdma_chan *chan, void *token, void *data,
 681                       int len, int directed)
 682 {
 683         struct cpdma_ctlr               *ctlr = chan->ctlr;
 684         struct cpdma_desc __iomem       *desc;
 685         dma_addr_t                      buffer;
 686         unsigned long                   flags;
 687         u32                             mode;
 688         int                             ret = 0;
 689
 690         spin_lock_irqsave(&chan->lock, flags);
 691
 692         if (chan->state == CPDMA_STATE_TEARDOWN) {
 693                 ret = -EINVAL;
 694                 goto unlock_ret;
 695         }
 696
 697         desc = cpdma_desc_alloc(ctlr->pool, 1, is_rx_chan(chan));
 698         if (!desc) {
 699                 chan->stats.desc_alloc_fail++;
 700                 ret = -ENOMEM;
 701                 goto unlock_ret;
 702         }
 703
 704         if (len < ctlr->params.min_packet_size) {
 705                 len = ctlr->params.min_packet_size;
 706                 chan->stats.runt_transmit_buff++;
 707         }
 708
 709         buffer = dma_map_single(ctlr->dev, data, len, chan->dir);
 710         ret = dma_mapping_error(ctlr->dev, buffer);
 711         if (ret) {
 712                 cpdma_desc_free(ctlr->pool, desc, 1);
 713                 ret = -EINVAL;
 714                 goto unlock_ret;
 715         }
 716
 717         mode = CPDMA_DESC_OWNER | CPDMA_DESC_SOP | CPDMA_DESC_EOP;
 718         cpdma_desc_to_port(chan, mode, directed);
 719
 720         desc_write(desc, hw_next,   0);
 721         desc_write(desc, hw_buffer, buffer);
 722         desc_write(desc, hw_len,    len);
 723         desc_write(desc, hw_mode,   mode | len);
 724         desc_write(desc, sw_token,  token);
 725         desc_write(desc, sw_buffer, buffer);
 726         desc_write(desc, sw_len,    len);
 727
 728         __cpdma_chan_submit(chan, desc);
 729
 730         if (chan->state == CPDMA_STATE_ACTIVE && chan->rxfree)
 731                 chan_write(chan, rxfree, 1);
 732
 733         chan->count++;
 734
 735 unlock_ret:
 736         spin_unlock_irqrestore(&chan->lock, flags);
 737         return ret;
 738 }
 739 EXPORT_SYMBOL_GPL(cpdma_chan_submit);
 740
 741 bool cpdma_check_free_tx_desc(struct cpdma_chan *chan)
 742 {
 743         unsigned long flags;
 744         int index;
 745         bool ret;
 746         struct cpdma_ctlr       *ctlr = chan->ctlr;
 747         struct cpdma_desc_pool  *pool = ctlr->pool;
 748
 749         spin_lock_irqsave(&pool->lock, flags);
 750
 751         index = bitmap_find_next_zero_area(pool->bitmap,
 752                                 pool->num_desc, pool->num_desc/2, 1, 0);
 753
 754         if (index < pool->num_desc)
 755                 ret = true;
 756         else
 757                 ret = false;
 758
 759         spin_unlock_irqrestore(&pool->lock, flags);
 760         return ret;
 761 }
 762 EXPORT_SYMBOL_GPL(cpdma_check_free_tx_desc);
 763
 764 static void __cpdma_chan_free(struct cpdma_chan *chan,
 765                               struct cpdma_desc __iomem *desc,
 766                               int outlen, int status)
 767 {
 768         struct cpdma_ctlr               *ctlr = chan->ctlr;
 769         struct cpdma_desc_pool          *pool = ctlr->pool;
 770         dma_addr_t                      buff_dma;
 771         int                             origlen;
 772         void                            *token;
 773
 774         token      = (void *)desc_read(desc, sw_token);
 775         buff_dma   = desc_read(desc, sw_buffer);
 776         origlen    = desc_read(desc, sw_len);
 777
 778         dma_unmap_single(ctlr->dev, buff_dma, origlen, chan->dir);
 779         cpdma_desc_free(pool, desc, 1);
 780         (*chan->handler)(token, outlen, status);
 781 }
 782
 783 static int __cpdma_chan_process(struct cpdma_chan *chan)
 784 {
 785         struct cpdma_ctlr               *ctlr = chan->ctlr;
 786         struct cpdma_desc __iomem       *desc;
 787         int                             status, outlen;
 788         int                             cb_status = 0;
 789         struct cpdma_desc_pool          *pool = ctlr->pool;
 790         dma_addr_t                      desc_dma;
 791         unsigned long                   flags;
 792
 793         spin_lock_irqsave(&chan->lock, flags);
 794
 795         desc = chan->head;
 796         if (!desc) {
 797                 chan->stats.empty_dequeue++;
 798                 status = -ENOENT;
 799                 goto unlock_ret;
 800         }
 801         desc_dma = desc_phys(pool, desc);
 802
 803         status  = __raw_readl(&desc->hw_mode);
 804         outlen  = status & 0x7ff;
 805         if (status & CPDMA_DESC_OWNER) {
 806                 chan->stats.busy_dequeue++;
 807                 status = -EBUSY;
 808                 goto unlock_ret;
 809         }
 810
 811         if (status & CPDMA_DESC_PASS_CRC)
 812                 outlen -= CPDMA_DESC_CRC_LEN;
 813
 814         status  = status & (CPDMA_DESC_EOQ | CPDMA_DESC_TD_COMPLETE |
 815                             CPDMA_DESC_PORT_MASK);
 816
 817         chan->head = desc_from_phys(pool, desc_read(desc, hw_next));
 818         chan_write(chan, cp, desc_dma);
 819         chan->count--;
 820         chan->stats.good_dequeue++;
 821
 822         if (status & CPDMA_DESC_EOQ) {
 823                 chan->stats.requeue++;
 824                 chan_write(chan, hdp, desc_phys(pool, chan->head));
 825         }
 826
 827         spin_unlock_irqrestore(&chan->lock, flags);
 828         if (unlikely(status & CPDMA_DESC_TD_COMPLETE))
 829                 cb_status = -ENOSYS;
 830         else
 831                 cb_status = status;
 832
 833         __cpdma_chan_free(chan, desc, outlen, cb_status);
 834         return status;
 835
 836 unlock_ret:
 837         spin_unlock_irqrestore(&chan->lock, flags);
 838         return status;
 839 }
 840
 841 int cpdma_chan_process(struct cpdma_chan *chan, int quota)
 842 {
 843         int used = 0, ret = 0;
 844
 845         if (chan->state != CPDMA_STATE_ACTIVE)
 846                 return -EINVAL;
 847
 848         while (used < quota) {
 849                 ret = __cpdma_chan_process(chan);
 850                 if (ret < 0)
 851                         break;
 852                 used++;
 853         }
 854         return used;
 855 }
 856 EXPORT_SYMBOL_GPL(cpdma_chan_process);
 857
 858 int cpdma_chan_start(struct cpdma_chan *chan)
 859 {
 860         struct cpdma_ctlr       *ctlr = chan->ctlr;
 861         struct cpdma_desc_pool  *pool = ctlr->pool;
 862         unsigned long           flags;
 863
 864         spin_lock_irqsave(&chan->lock, flags);
 865         if (chan->state != CPDMA_STATE_IDLE) {
 866                 spin_unlock_irqrestore(&chan->lock, flags);
 867                 return -EBUSY;
 868         }
 869         if (ctlr->state != CPDMA_STATE_ACTIVE) {
 870                 spin_unlock_irqrestore(&chan->lock, flags);
 871                 return -EINVAL;
 872         }
 873         dma_reg_write(ctlr, chan->int_set, chan->mask);
 874         chan->state = CPDMA_STATE_ACTIVE;
 875         if (chan->head) {
 876                 chan_write(chan, hdp, desc_phys(pool, chan->head));
 877                 if (chan->rxfree)
 878                         chan_write(chan, rxfree, chan->count);
 879         }
 880
 881         spin_unlock_irqrestore(&chan->lock, flags);
 882         return 0;
 883 }
 884 EXPORT_SYMBOL_GPL(cpdma_chan_start);
 885
 886 int cpdma_chan_stop(struct cpdma_chan *chan)
 887 {
 888         struct cpdma_ctlr       *ctlr = chan->ctlr;
 889         struct cpdma_desc_pool  *pool = ctlr->pool;
 890         unsigned long           flags;
 891         int                     ret;
 892         unsigned                timeout;
 893
 894         spin_lock_irqsave(&chan->lock, flags);
 895         if (chan->state != CPDMA_STATE_ACTIVE) {
 896                 spin_unlock_irqrestore(&chan->lock, flags);
 897                 return -EINVAL;
 898         }
 899
 900         chan->state = CPDMA_STATE_TEARDOWN;
 901         dma_reg_write(ctlr, chan->int_clear, chan->mask);
 902
 903         /* trigger teardown */
 904         dma_reg_write(ctlr, chan->td, chan_linear(chan));
 905
 906         /* wait for teardown complete */
 907         timeout = 100 * 100; /* 100 ms */
 908         while (timeout) {
 909                 u32 cp = chan_read(chan, cp);
 910                 if ((cp & CPDMA_TEARDOWN_VALUE) == CPDMA_TEARDOWN_VALUE)
 911                         break;
 912                 udelay(10);
 913                 timeout--;
 914         }
 915         WARN_ON(!timeout);
 916         chan_write(chan, cp, CPDMA_TEARDOWN_VALUE);
 917
 918         /* handle completed packets */
 919         spin_unlock_irqrestore(&chan->lock, flags);
 920         do {
 921                 ret = __cpdma_chan_process(chan);
 922                 if (ret < 0)
 923                         break;
 924         } while ((ret & CPDMA_DESC_TD_COMPLETE) == 0);
 925         spin_lock_irqsave(&chan->lock, flags);
 926
 927         /* remaining packets haven't been tx/rx'ed, clean them up */
 928         while (chan->head) {
 929                 struct cpdma_desc __iomem *desc = chan->head;
 930                 dma_addr_t next_dma;
 931
 932                 next_dma = desc_read(desc, hw_next);
 933                 chan->head = desc_from_phys(pool, next_dma);
 934                 chan->count--;
 935                 chan->stats.teardown_dequeue++;
 936
 937                 /* issue callback without locks held */
 938                 spin_unlock_irqrestore(&chan->lock, flags);
 939                 __cpdma_chan_free(chan, desc, 0, -ENOSYS);
 940                 spin_lock_irqsave(&chan->lock, flags);
 941         }
 942
 943         chan->state = CPDMA_STATE_IDLE;
 944         spin_unlock_irqrestore(&chan->lock, flags);
 945         return 0;
 946 }
 947 EXPORT_SYMBOL_GPL(cpdma_chan_stop);
 948
 949 int cpdma_chan_int_ctrl(struct cpdma_chan *chan, bool enable)
 950 {
 951         unsigned long flags;
 952
 953         spin_lock_irqsave(&chan->lock, flags);
 954         if (chan->state != CPDMA_STATE_ACTIVE) {
 955                 spin_unlock_irqrestore(&chan->lock, flags);
 956                 return -EINVAL;
 957         }
 958
 959         dma_reg_write(chan->ctlr, enable ? chan->int_set : chan->int_clear,
 960                       chan->mask);
 961         spin_unlock_irqrestore(&chan->lock, flags);
 962
 963         return 0;
 964 }
 965
 966 struct cpdma_control_info {
 967         u32             reg;
 968         u32             shift, mask;
 969         int             access;
 970 #define ACCESS_RO       BIT(0)
 971 #define ACCESS_WO       BIT(1)
 972 #define ACCESS_RW       (ACCESS_RO | ACCESS_WO)
 973 };
 974
 975 struct cpdma_control_info controls[] = {
 976         [CPDMA_CMD_IDLE]          = {CPDMA_DMACONTROL,  3,  1,      ACCESS_WO},
 977         [CPDMA_COPY_ERROR_FRAMES] = {CPDMA_DMACONTROL,  4,  1,      ACCESS_RW},
 978         [CPDMA_RX_OFF_LEN_UPDATE] = {CPDMA_DMACONTROL,  2,  1,      ACCESS_RW},
 979         [CPDMA_RX_OWNERSHIP_FLIP] = {CPDMA_DMACONTROL,  1,  1,      ACCESS_RW},
 980         [CPDMA_TX_PRIO_FIXED]     = {CPDMA_DMACONTROL,  0,  1,      ACCESS_RW},
 981         [CPDMA_STAT_IDLE]         = {CPDMA_DMASTATUS,   31, 1,      ACCESS_RO},
 982         [CPDMA_STAT_TX_ERR_CODE]  = {CPDMA_DMASTATUS,   20, 0xf,    ACCESS_RW},
 983         [CPDMA_STAT_TX_ERR_CHAN]  = {CPDMA_DMASTATUS,   16, 0x7,    ACCESS_RW},
 984         [CPDMA_STAT_RX_ERR_CODE]  = {CPDMA_DMASTATUS,   12, 0xf,    ACCESS_RW},
 985         [CPDMA_STAT_RX_ERR_CHAN]  = {CPDMA_DMASTATUS,   8,  0x7,    ACCESS_RW},
 986         [CPDMA_RX_BUFFER_OFFSET]  = {CPDMA_RXBUFFOFS,   0,  0xffff, ACCESS_RW},
 987 };
 988
 989 int cpdma_control_get(struct cpdma_ctlr *ctlr, int control)
 990 {
 991         unsigned long flags;
 992         struct cpdma_control_info *info = &controls[control];
 993         int ret;
 994
 995         spin_lock_irqsave(&ctlr->lock, flags);
 996
 997         ret = -ENOTSUPP;
 998         if (!ctlr->params.has_ext_regs)
 999                 goto unlock_ret;
1000
1001         ret = -EINVAL;
1002         if (ctlr->state != CPDMA_STATE_ACTIVE)
1003                 goto unlock_ret;
1004
1005         ret = -ENOENT;
1006         if (control < 0 || control >= ARRAY_SIZE(controls))
1007                 goto unlock_ret;
1008
1009         ret = -EPERM;
1010         if ((info->access & ACCESS_RO) != ACCESS_RO)
1011                 goto unlock_ret;
1012
1013         ret = (dma_reg_read(ctlr, info->reg) >> info->shift) & info->mask;
1014
1015 unlock_ret:
1016         spin_unlock_irqrestore(&ctlr->lock, flags);
1017         return ret;
1018 }
1019
1020 int cpdma_control_set(struct cpdma_ctlr *ctlr, int control, int value)
1021 {
1022         unsigned long flags;
1023         struct cpdma_control_info *info = &controls[control];
1024         int ret;
1025         u32 val;
1026
1027         spin_lock_irqsave(&ctlr->lock, flags);
1028
1029         ret = -ENOTSUPP;
1030         if (!ctlr->params.has_ext_regs)
1031                 goto unlock_ret;
1032
1033         ret = -EINVAL;
1034         if (ctlr->state != CPDMA_STATE_ACTIVE)
1035                 goto unlock_ret;
1036
1037         ret = -ENOENT;
1038         if (control < 0 || control >= ARRAY_SIZE(controls))
1039                 goto unlock_ret;
1040
1041         ret = -EPERM;
1042         if ((info->access & ACCESS_WO) != ACCESS_WO)
1043                 goto unlock_ret;
1044
1045         val  = dma_reg_read(ctlr, info->reg);
1046         val &= ~(info->mask << info->shift);
1047         val |= (value & info->mask) << info->shift;
1048         dma_reg_write(ctlr, info->reg, val);
1049         ret = 0;
1050
1051 unlock_ret:
1052         spin_unlock_irqrestore(&ctlr->lock, flags);
1053         return ret;
1054 }
1055 EXPORT_SYMBOL_GPL(cpdma_control_set);
1056
1057 MODULE_LICENSE("GPL");