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         phys_addr_t             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 long)desc - (__force long)pool->iomap;
 223 }
 224
 225 static inline struct cpdma_desc __iomem *
 226 desc_from_phys(struct cpdma_desc_pool *pool, dma_addr_t dma)
 227 {
 228         return dma ? pool->iomap + dma - pool->hw_addr : NULL;
 229 }
 230
 231 static struct cpdma_desc __iomem *
 232 cpdma_desc_alloc(struct cpdma_desc_pool *pool, int num_desc, bool is_rx)
 233 {
 234         unsigned long flags;
 235         int index;
 236         int desc_start;
 237         int desc_end;
 238         struct cpdma_desc __iomem *desc = NULL;
 239
 240         spin_lock_irqsave(&pool->lock, flags);
 241
 242         if (is_rx) {
 243                 desc_start = 0;
 244                 desc_end = pool->num_desc/2;
 245          } else {
 246                 desc_start = pool->num_desc/2;
 247                 desc_end = pool->num_desc;
 248         }
 249
 250         index = bitmap_find_next_zero_area(pool->bitmap,
 251                                 desc_end, desc_start, num_desc, 0);
 252         if (index < desc_end) {
 253                 bitmap_set(pool->bitmap, index, num_desc);
 254                 desc = pool->iomap + pool->desc_size * index;
 255                 pool->used_desc++;
 256         }
 257
 258         spin_unlock_irqrestore(&pool->lock, flags);
 259         return desc;
 260 }
 261
 262 static void cpdma_desc_free(struct cpdma_desc_pool *pool,
 263                             struct cpdma_desc __iomem *desc, int num_desc)
 264 {
 265         unsigned long flags, index;
 266
 267         index = ((unsigned long)desc - (unsigned long)pool->iomap) /
 268                 pool->desc_size;
 269         spin_lock_irqsave(&pool->lock, flags);
 270         bitmap_clear(pool->bitmap, index, num_desc);
 271         pool->used_desc--;
 272         spin_unlock_irqrestore(&pool->lock, flags);
 273 }
 274
 275 struct cpdma_ctlr *cpdma_ctlr_create(struct cpdma_params *params)
 276 {
 277         struct cpdma_ctlr *ctlr;
 278
 279         ctlr = kzalloc(sizeof(*ctlr), GFP_KERNEL);
 280         if (!ctlr)
 281                 return NULL;
 282
 283         ctlr->state = CPDMA_STATE_IDLE;
 284         ctlr->params = *params;
 285         ctlr->dev = params->dev;
 286         spin_lock_init(&ctlr->lock);
 287
 288         ctlr->pool = cpdma_desc_pool_create(ctlr->dev,
 289                                             ctlr->params.desc_mem_phys,
 290                                             ctlr->params.desc_hw_addr,
 291                                             ctlr->params.desc_mem_size,
 292                                             ctlr->params.desc_align);
 293         if (!ctlr->pool) {
 294                 kfree(ctlr);
 295                 return NULL;
 296         }
 297
 298         if (WARN_ON(ctlr->num_chan > CPDMA_MAX_CHANNELS))
 299                 ctlr->num_chan = CPDMA_MAX_CHANNELS;
 300         return ctlr;
 301 }
 302 EXPORT_SYMBOL_GPL(cpdma_ctlr_create);
 303
 304 int cpdma_ctlr_start(struct cpdma_ctlr *ctlr)
 305 {
 306         unsigned long flags;
 307         int i;
 308
 309         spin_lock_irqsave(&ctlr->lock, flags);
 310         if (ctlr->state != CPDMA_STATE_IDLE) {
 311                 spin_unlock_irqrestore(&ctlr->lock, flags);
 312                 return -EBUSY;
 313         }
 314
 315         if (ctlr->params.has_soft_reset) {
 316                 unsigned timeout = 10 * 100;
 317
 318                 dma_reg_write(ctlr, CPDMA_SOFTRESET, 1);
 319                 while (timeout) {
 320                         if (dma_reg_read(ctlr, CPDMA_SOFTRESET) == 0)
 321                                 break;
 322                         udelay(10);
 323                         timeout--;
 324                 }
 325                 WARN_ON(!timeout);
 326         }
 327
 328         for (i = 0; i < ctlr->num_chan; i++) {
 329                 __raw_writel(0, ctlr->params.txhdp + 4 * i);
 330                 __raw_writel(0, ctlr->params.rxhdp + 4 * i);
 331                 __raw_writel(0, ctlr->params.txcp + 4 * i);
 332                 __raw_writel(0, ctlr->params.rxcp + 4 * i);
 333         }
 334
 335         dma_reg_write(ctlr, CPDMA_RXINTMASKCLEAR, 0xffffffff);
 336         dma_reg_write(ctlr, CPDMA_TXINTMASKCLEAR, 0xffffffff);
 337
 338         dma_reg_write(ctlr, CPDMA_TXCONTROL, 1);
 339         dma_reg_write(ctlr, CPDMA_RXCONTROL, 1);
 340
 341         ctlr->state = CPDMA_STATE_ACTIVE;
 342
 343         for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) {
 344                 if (ctlr->channels[i])
 345                         cpdma_chan_start(ctlr->channels[i]);
 346         }
 347         spin_unlock_irqrestore(&ctlr->lock, flags);
 348         return 0;
 349 }
 350 EXPORT_SYMBOL_GPL(cpdma_ctlr_start);
 351
 352 int cpdma_ctlr_stop(struct cpdma_ctlr *ctlr)
 353 {
 354         unsigned long flags;
 355         int i;
 356
 357         spin_lock_irqsave(&ctlr->lock, flags);
 358         if (ctlr->state != CPDMA_STATE_ACTIVE) {
 359                 spin_unlock_irqrestore(&ctlr->lock, flags);
 360                 return -EINVAL;
 361         }
 362
 363         ctlr->state = CPDMA_STATE_TEARDOWN;
 364
 365         for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) {
 366                 if (ctlr->channels[i])
 367                         cpdma_chan_stop(ctlr->channels[i]);
 368         }
 369
 370         dma_reg_write(ctlr, CPDMA_RXINTMASKCLEAR, 0xffffffff);
 371         dma_reg_write(ctlr, CPDMA_TXINTMASKCLEAR, 0xffffffff);
 372
 373         dma_reg_write(ctlr, CPDMA_TXCONTROL, 0);
 374         dma_reg_write(ctlr, CPDMA_RXCONTROL, 0);
 375
 376         ctlr->state = CPDMA_STATE_IDLE;
 377
 378         spin_unlock_irqrestore(&ctlr->lock, flags);
 379         return 0;
 380 }
 381 EXPORT_SYMBOL_GPL(cpdma_ctlr_stop);
 382
 383 int cpdma_ctlr_dump(struct cpdma_ctlr *ctlr)
 384 {
 385         struct device *dev = ctlr->dev;
 386         unsigned long flags;
 387         int i;
 388
 389         spin_lock_irqsave(&ctlr->lock, flags);
 390
 391         dev_info(dev, "CPDMA: state: %s", cpdma_state_str[ctlr->state]);
 392
 393         dev_info(dev, "CPDMA: txidver: %x",
 394                  dma_reg_read(ctlr, CPDMA_TXIDVER));
 395         dev_info(dev, "CPDMA: txcontrol: %x",
 396                  dma_reg_read(ctlr, CPDMA_TXCONTROL));
 397         dev_info(dev, "CPDMA: txteardown: %x",
 398                  dma_reg_read(ctlr, CPDMA_TXTEARDOWN));
 399         dev_info(dev, "CPDMA: rxidver: %x",
 400                  dma_reg_read(ctlr, CPDMA_RXIDVER));
 401         dev_info(dev, "CPDMA: rxcontrol: %x",
 402                  dma_reg_read(ctlr, CPDMA_RXCONTROL));
 403         dev_info(dev, "CPDMA: softreset: %x",
 404                  dma_reg_read(ctlr, CPDMA_SOFTRESET));
 405         dev_info(dev, "CPDMA: rxteardown: %x",
 406                  dma_reg_read(ctlr, CPDMA_RXTEARDOWN));
 407         dev_info(dev, "CPDMA: txintstatraw: %x",
 408                  dma_reg_read(ctlr, CPDMA_TXINTSTATRAW));
 409         dev_info(dev, "CPDMA: txintstatmasked: %x",
 410                  dma_reg_read(ctlr, CPDMA_TXINTSTATMASKED));
 411         dev_info(dev, "CPDMA: txintmaskset: %x",
 412                  dma_reg_read(ctlr, CPDMA_TXINTMASKSET));
 413         dev_info(dev, "CPDMA: txintmaskclear: %x",
 414                  dma_reg_read(ctlr, CPDMA_TXINTMASKCLEAR));
 415         dev_info(dev, "CPDMA: macinvector: %x",
 416                  dma_reg_read(ctlr, CPDMA_MACINVECTOR));
 417         dev_info(dev, "CPDMA: maceoivector: %x",
 418                  dma_reg_read(ctlr, CPDMA_MACEOIVECTOR));
 419         dev_info(dev, "CPDMA: rxintstatraw: %x",
 420                  dma_reg_read(ctlr, CPDMA_RXINTSTATRAW));
 421         dev_info(dev, "CPDMA: rxintstatmasked: %x",
 422                  dma_reg_read(ctlr, CPDMA_RXINTSTATMASKED));
 423         dev_info(dev, "CPDMA: rxintmaskset: %x",
 424                  dma_reg_read(ctlr, CPDMA_RXINTMASKSET));
 425         dev_info(dev, "CPDMA: rxintmaskclear: %x",
 426                  dma_reg_read(ctlr, CPDMA_RXINTMASKCLEAR));
 427         dev_info(dev, "CPDMA: dmaintstatraw: %x",
 428                  dma_reg_read(ctlr, CPDMA_DMAINTSTATRAW));
 429         dev_info(dev, "CPDMA: dmaintstatmasked: %x",
 430                  dma_reg_read(ctlr, CPDMA_DMAINTSTATMASKED));
 431         dev_info(dev, "CPDMA: dmaintmaskset: %x",
 432                  dma_reg_read(ctlr, CPDMA_DMAINTMASKSET));
 433         dev_info(dev, "CPDMA: dmaintmaskclear: %x",
 434                  dma_reg_read(ctlr, CPDMA_DMAINTMASKCLEAR));
 435
 436         if (!ctlr->params.has_ext_regs) {
 437                 dev_info(dev, "CPDMA: dmacontrol: %x",
 438                          dma_reg_read(ctlr, CPDMA_DMACONTROL));
 439                 dev_info(dev, "CPDMA: dmastatus: %x",
 440                          dma_reg_read(ctlr, CPDMA_DMASTATUS));
 441                 dev_info(dev, "CPDMA: rxbuffofs: %x",
 442                          dma_reg_read(ctlr, CPDMA_RXBUFFOFS));
 443         }
 444
 445         for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++)
 446                 if (ctlr->channels[i])
 447                         cpdma_chan_dump(ctlr->channels[i]);
 448
 449         spin_unlock_irqrestore(&ctlr->lock, flags);
 450         return 0;
 451 }
 452 EXPORT_SYMBOL_GPL(cpdma_ctlr_dump);
 453
 454 int cpdma_ctlr_destroy(struct cpdma_ctlr *ctlr)
 455 {
 456         unsigned long flags;
 457         int ret = 0, i;
 458
 459         if (!ctlr)
 460                 return -EINVAL;
 461
 462         spin_lock_irqsave(&ctlr->lock, flags);
 463         if (ctlr->state != CPDMA_STATE_IDLE)
 464                 cpdma_ctlr_stop(ctlr);
 465
 466         for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++)
 467                 cpdma_chan_destroy(ctlr->channels[i]);
 468
 469         cpdma_desc_pool_destroy(ctlr->pool);
 470         spin_unlock_irqrestore(&ctlr->lock, flags);
 471         kfree(ctlr);
 472         return ret;
 473 }
 474 EXPORT_SYMBOL_GPL(cpdma_ctlr_destroy);
 475
 476 int cpdma_ctlr_int_ctrl(struct cpdma_ctlr *ctlr, bool enable)
 477 {
 478         unsigned long flags;
 479         int i, reg;
 480
 481         spin_lock_irqsave(&ctlr->lock, flags);
 482         if (ctlr->state != CPDMA_STATE_ACTIVE) {
 483                 spin_unlock_irqrestore(&ctlr->lock, flags);
 484                 return -EINVAL;
 485         }
 486
 487         reg = enable ? CPDMA_DMAINTMASKSET : CPDMA_DMAINTMASKCLEAR;
 488         dma_reg_write(ctlr, reg, CPDMA_DMAINT_HOSTERR);
 489
 490         for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) {
 491                 if (ctlr->channels[i])
 492                         cpdma_chan_int_ctrl(ctlr->channels[i], enable);
 493         }
 494
 495         spin_unlock_irqrestore(&ctlr->lock, flags);
 496         return 0;
 497 }
 498 EXPORT_SYMBOL_GPL(cpdma_ctlr_int_ctrl);
 499
 500 void cpdma_ctlr_eoi(struct cpdma_ctlr *ctlr, u32 value)
 501 {
 502         dma_reg_write(ctlr, CPDMA_MACEOIVECTOR, value);
 503 }
 504 EXPORT_SYMBOL_GPL(cpdma_ctlr_eoi);
 505
 506 struct cpdma_chan *cpdma_chan_create(struct cpdma_ctlr *ctlr, int chan_num,
 507                                      cpdma_handler_fn handler)
 508 {
 509         struct cpdma_chan *chan;
 510         int ret, offset = (chan_num % CPDMA_MAX_CHANNELS) * 4;
 511         unsigned long flags;
 512
 513         if (__chan_linear(chan_num) >= ctlr->num_chan)
 514                 return NULL;
 515
 516         ret = -ENOMEM;
 517         chan = kzalloc(sizeof(*chan), GFP_KERNEL);
 518         if (!chan)
 519                 goto err_chan_alloc;
 520
 521         spin_lock_irqsave(&ctlr->lock, flags);
 522         ret = -EBUSY;
 523         if (ctlr->channels[chan_num])
 524                 goto err_chan_busy;
 525
 526         chan->ctlr      = ctlr;
 527         chan->state     = CPDMA_STATE_IDLE;
 528         chan->chan_num  = chan_num;
 529         chan->handler   = handler;
 530
 531         if (is_rx_chan(chan)) {
 532                 chan->hdp       = ctlr->params.rxhdp + offset;
 533                 chan->cp        = ctlr->params.rxcp + offset;
 534                 chan->rxfree    = ctlr->params.rxfree + offset;
 535                 chan->int_set   = CPDMA_RXINTMASKSET;
 536                 chan->int_clear = CPDMA_RXINTMASKCLEAR;
 537                 chan->td        = CPDMA_RXTEARDOWN;
 538                 chan->dir       = DMA_FROM_DEVICE;
 539         } else {
 540                 chan->hdp       = ctlr->params.txhdp + offset;
 541                 chan->cp        = ctlr->params.txcp + offset;
 542                 chan->int_set   = CPDMA_TXINTMASKSET;
 543                 chan->int_clear = CPDMA_TXINTMASKCLEAR;
 544                 chan->td        = CPDMA_TXTEARDOWN;
 545                 chan->dir       = DMA_TO_DEVICE;
 546         }
 547         chan->mask = BIT(chan_linear(chan));
 548
 549         spin_lock_init(&chan->lock);
 550
 551         ctlr->channels[chan_num] = chan;
 552         spin_unlock_irqrestore(&ctlr->lock, flags);
 553         return chan;
 554
 555 err_chan_busy:
 556         spin_unlock_irqrestore(&ctlr->lock, flags);
 557         kfree(chan);
 558 err_chan_alloc:
 559         return ERR_PTR(ret);
 560 }
 561 EXPORT_SYMBOL_GPL(cpdma_chan_create);
 562
 563 int cpdma_chan_destroy(struct cpdma_chan *chan)
 564 {
 565         struct cpdma_ctlr *ctlr;
 566         unsigned long flags;
 567
 568         if (!chan)
 569                 return -EINVAL;
 570         ctlr = chan->ctlr;
 571
 572         spin_lock_irqsave(&ctlr->lock, flags);
 573         if (chan->state != CPDMA_STATE_IDLE)
 574                 cpdma_chan_stop(chan);
 575         ctlr->channels[chan->chan_num] = NULL;
 576         spin_unlock_irqrestore(&ctlr->lock, flags);
 577         kfree(chan);
 578         return 0;
 579 }
 580 EXPORT_SYMBOL_GPL(cpdma_chan_destroy);
 581
 582 int cpdma_chan_get_stats(struct cpdma_chan *chan,
 583                          struct cpdma_chan_stats *stats)
 584 {
 585         unsigned long flags;
 586         if (!chan)
 587                 return -EINVAL;
 588         spin_lock_irqsave(&chan->lock, flags);
 589         memcpy(stats, &chan->stats, sizeof(*stats));
 590         spin_unlock_irqrestore(&chan->lock, flags);
 591         return 0;
 592 }
 593 EXPORT_SYMBOL_GPL(cpdma_chan_get_stats);
 594
 595 int cpdma_chan_dump(struct cpdma_chan *chan)
 596 {
 597         unsigned long flags;
 598         struct device *dev = chan->ctlr->dev;
 599
 600         spin_lock_irqsave(&chan->lock, flags);
 601
 602         dev_info(dev, "channel %d (%s %d) state %s",
 603                  chan->chan_num, is_rx_chan(chan) ? "rx" : "tx",
 604                  chan_linear(chan), cpdma_state_str[chan->state]);
 605         dev_info(dev, "\thdp: %x\n", chan_read(chan, hdp));
 606         dev_info(dev, "\tcp: %x\n", chan_read(chan, cp));
 607         if (chan->rxfree) {
 608                 dev_info(dev, "\trxfree: %x\n",
 609                          chan_read(chan, rxfree));
 610         }
 611
 612         dev_info(dev, "\tstats head_enqueue: %d\n",
 613                  chan->stats.head_enqueue);
 614         dev_info(dev, "\tstats tail_enqueue: %d\n",
 615                  chan->stats.tail_enqueue);
 616         dev_info(dev, "\tstats pad_enqueue: %d\n",
 617                  chan->stats.pad_enqueue);
 618         dev_info(dev, "\tstats misqueued: %d\n",
 619                  chan->stats.misqueued);
 620         dev_info(dev, "\tstats desc_alloc_fail: %d\n",
 621                  chan->stats.desc_alloc_fail);
 622         dev_info(dev, "\tstats pad_alloc_fail: %d\n",
 623                  chan->stats.pad_alloc_fail);
 624         dev_info(dev, "\tstats runt_receive_buff: %d\n",
 625                  chan->stats.runt_receive_buff);
 626         dev_info(dev, "\tstats runt_transmit_buff: %d\n",
 627                  chan->stats.runt_transmit_buff);
 628         dev_info(dev, "\tstats empty_dequeue: %d\n",
 629                  chan->stats.empty_dequeue);
 630         dev_info(dev, "\tstats busy_dequeue: %d\n",
 631                  chan->stats.busy_dequeue);
 632         dev_info(dev, "\tstats good_dequeue: %d\n",
 633                  chan->stats.good_dequeue);
 634         dev_info(dev, "\tstats requeue: %d\n",
 635                  chan->stats.requeue);
 636         dev_info(dev, "\tstats teardown_dequeue: %d\n",
 637                  chan->stats.teardown_dequeue);
 638
 639         spin_unlock_irqrestore(&chan->lock, flags);
 640         return 0;
 641 }
 642
 643 static void __cpdma_chan_submit(struct cpdma_chan *chan,
 644                                 struct cpdma_desc __iomem *desc)
 645 {
 646         struct cpdma_ctlr               *ctlr = chan->ctlr;
 647         struct cpdma_desc __iomem       *prev = chan->tail;
 648         struct cpdma_desc_pool          *pool = ctlr->pool;
 649         dma_addr_t                      desc_dma;
 650         u32                             mode;
 651
 652         desc_dma = desc_phys(pool, desc);
 653
 654         /* simple case - idle channel */
 655         if (!chan->head) {
 656                 chan->stats.head_enqueue++;
 657                 chan->head = desc;
 658                 chan->tail = desc;
 659                 if (chan->state == CPDMA_STATE_ACTIVE)
 660                         chan_write(chan, hdp, desc_dma);
 661                 return;
 662         }
 663
 664         /* first chain the descriptor at the tail of the list */
 665         desc_write(prev, hw_next, desc_dma);
 666         chan->tail = desc;
 667         chan->stats.tail_enqueue++;
 668
 669         /* next check if EOQ has been triggered already */
 670         mode = desc_read(prev, hw_mode);
 671         if (((mode & (CPDMA_DESC_EOQ | CPDMA_DESC_OWNER)) == CPDMA_DESC_EOQ) &&
 672             (chan->state == CPDMA_STATE_ACTIVE)) {
 673                 desc_write(prev, hw_mode, mode & ~CPDMA_DESC_EOQ);
 674                 chan_write(chan, hdp, desc_dma);
 675                 chan->stats.misqueued++;
 676         }
 677 }
 678
 679 int cpdma_chan_submit(struct cpdma_chan *chan, void *token, void *data,
 680                       int len, int directed)
 681 {
 682         struct cpdma_ctlr               *ctlr = chan->ctlr;
 683         struct cpdma_desc __iomem       *desc;
 684         dma_addr_t                      buffer;
 685         unsigned long                   flags;
 686         u32                             mode;
 687         int                             ret = 0;
 688
 689         spin_lock_irqsave(&chan->lock, flags);
 690
 691         if (chan->state == CPDMA_STATE_TEARDOWN) {
 692                 ret = -EINVAL;
 693                 goto unlock_ret;
 694         }
 695
 696         desc = cpdma_desc_alloc(ctlr->pool, 1, is_rx_chan(chan));
 697         if (!desc) {
 698                 chan->stats.desc_alloc_fail++;
 699                 ret = -ENOMEM;
 700                 goto unlock_ret;
 701         }
 702
 703         if (len < ctlr->params.min_packet_size) {
 704                 len = ctlr->params.min_packet_size;
 705                 chan->stats.runt_transmit_buff++;
 706         }
 707
 708         buffer = dma_map_single(ctlr->dev, data, len, chan->dir);
 709         ret = dma_mapping_error(ctlr->dev, buffer);
 710         if (ret) {
 711                 cpdma_desc_free(ctlr->pool, desc, 1);
 712                 ret = -EINVAL;
 713                 goto unlock_ret;
 714         }
 715
 716         mode = CPDMA_DESC_OWNER | CPDMA_DESC_SOP | CPDMA_DESC_EOP;
 717         cpdma_desc_to_port(chan, mode, directed);
 718
 719         desc_write(desc, hw_next,   0);
 720         desc_write(desc, hw_buffer, buffer);
 721         desc_write(desc, hw_len,    len);
 722         desc_write(desc, hw_mode,   mode | len);
 723         desc_write(desc, sw_token,  token);
 724         desc_write(desc, sw_buffer, buffer);
 725         desc_write(desc, sw_len,    len);
 726
 727         __cpdma_chan_submit(chan, desc);
 728
 729         if (chan->state == CPDMA_STATE_ACTIVE && chan->rxfree)
 730                 chan_write(chan, rxfree, 1);
 731
 732         chan->count++;
 733
 734 unlock_ret:
 735         spin_unlock_irqrestore(&chan->lock, flags);
 736         return ret;
 737 }
 738 EXPORT_SYMBOL_GPL(cpdma_chan_submit);
 739
 740 bool cpdma_check_free_tx_desc(struct cpdma_chan *chan)
 741 {
 742         unsigned long flags;
 743         int index;
 744         bool ret;
 745         struct cpdma_ctlr       *ctlr = chan->ctlr;
 746         struct cpdma_desc_pool  *pool = ctlr->pool;
 747
 748         spin_lock_irqsave(&pool->lock, flags);
 749
 750         index = bitmap_find_next_zero_area(pool->bitmap,
 751                                 pool->num_desc, pool->num_desc/2, 1, 0);
 752
 753         if (index < pool->num_desc)
 754                 ret = true;
 755         else
 756                 ret = false;
 757
 758         spin_unlock_irqrestore(&pool->lock, flags);
 759         return ret;
 760 }
 761 EXPORT_SYMBOL_GPL(cpdma_check_free_tx_desc);
 762
 763 static void __cpdma_chan_free(struct cpdma_chan *chan,
 764                               struct cpdma_desc __iomem *desc,
 765                               int outlen, int status)
 766 {
 767         struct cpdma_ctlr               *ctlr = chan->ctlr;
 768         struct cpdma_desc_pool          *pool = ctlr->pool;
 769         dma_addr_t                      buff_dma;
 770         int                             origlen;
 771         void                            *token;
 772
 773         token      = (void *)desc_read(desc, sw_token);
 774         buff_dma   = desc_read(desc, sw_buffer);
 775         origlen    = desc_read(desc, sw_len);
 776
 777         dma_unmap_single(ctlr->dev, buff_dma, origlen, chan->dir);
 778         cpdma_desc_free(pool, desc, 1);
 779         (*chan->handler)(token, outlen, status);
 780 }
 781
 782 static int __cpdma_chan_process(struct cpdma_chan *chan)
 783 {
 784         struct cpdma_ctlr               *ctlr = chan->ctlr;
 785         struct cpdma_desc __iomem       *desc;
 786         int                             status, outlen;
 787         int                             cb_status = 0;
 788         struct cpdma_desc_pool          *pool = ctlr->pool;
 789         dma_addr_t                      desc_dma;
 790         unsigned long                   flags;
 791
 792         spin_lock_irqsave(&chan->lock, flags);
 793
 794         desc = chan->head;
 795         if (!desc) {
 796                 chan->stats.empty_dequeue++;
 797                 status = -ENOENT;
 798                 goto unlock_ret;
 799         }
 800         desc_dma = desc_phys(pool, desc);
 801
 802         status  = __raw_readl(&desc->hw_mode);
 803         outlen  = status & 0x7ff;
 804         if (status & CPDMA_DESC_OWNER) {
 805                 chan->stats.busy_dequeue++;
 806                 status = -EBUSY;
 807                 goto unlock_ret;
 808         }
 809
 810         if (status & CPDMA_DESC_PASS_CRC)
 811                 outlen -= CPDMA_DESC_CRC_LEN;
 812
 813         status  = status & (CPDMA_DESC_EOQ | CPDMA_DESC_TD_COMPLETE |
 814                             CPDMA_DESC_PORT_MASK);
 815
 816         chan->head = desc_from_phys(pool, desc_read(desc, hw_next));
 817         chan_write(chan, cp, desc_dma);
 818         chan->count--;
 819         chan->stats.good_dequeue++;
 820
 821         if (status & CPDMA_DESC_EOQ) {
 822                 chan->stats.requeue++;
 823                 chan_write(chan, hdp, desc_phys(pool, chan->head));
 824         }
 825
 826         spin_unlock_irqrestore(&chan->lock, flags);
 827         if (unlikely(status & CPDMA_DESC_TD_COMPLETE))
 828                 cb_status = -ENOSYS;
 829         else
 830                 cb_status = status;
 831
 832         __cpdma_chan_free(chan, desc, outlen, cb_status);
 833         return status;
 834
 835 unlock_ret:
 836         spin_unlock_irqrestore(&chan->lock, flags);
 837         return status;
 838 }
 839
 840 int cpdma_chan_process(struct cpdma_chan *chan, int quota)
 841 {
 842         int used = 0, ret = 0;
 843
 844         if (chan->state != CPDMA_STATE_ACTIVE)
 845                 return -EINVAL;
 846
 847         while (used < quota) {
 848                 ret = __cpdma_chan_process(chan);
 849                 if (ret < 0)
 850                         break;
 851                 used++;
 852         }
 853         return used;
 854 }
 855 EXPORT_SYMBOL_GPL(cpdma_chan_process);
 856
 857 int cpdma_chan_start(struct cpdma_chan *chan)
 858 {
 859         struct cpdma_ctlr       *ctlr = chan->ctlr;
 860         struct cpdma_desc_pool  *pool = ctlr->pool;
 861         unsigned long           flags;
 862
 863         spin_lock_irqsave(&chan->lock, flags);
 864         if (chan->state != CPDMA_STATE_IDLE) {
 865                 spin_unlock_irqrestore(&chan->lock, flags);
 866                 return -EBUSY;
 867         }
 868         if (ctlr->state != CPDMA_STATE_ACTIVE) {
 869                 spin_unlock_irqrestore(&chan->lock, flags);
 870                 return -EINVAL;
 871         }
 872         dma_reg_write(ctlr, chan->int_set, chan->mask);
 873         chan->state = CPDMA_STATE_ACTIVE;
 874         if (chan->head) {
 875                 chan_write(chan, hdp, desc_phys(pool, chan->head));
 876                 if (chan->rxfree)
 877                         chan_write(chan, rxfree, chan->count);
 878         }
 879
 880         spin_unlock_irqrestore(&chan->lock, flags);
 881         return 0;
 882 }
 883 EXPORT_SYMBOL_GPL(cpdma_chan_start);
 884
 885 int cpdma_chan_stop(struct cpdma_chan *chan)
 886 {
 887         struct cpdma_ctlr       *ctlr = chan->ctlr;
 888         struct cpdma_desc_pool  *pool = ctlr->pool;
 889         unsigned long           flags;
 890         int                     ret;
 891         unsigned                timeout;
 892
 893         spin_lock_irqsave(&chan->lock, flags);
 894         if (chan->state != CPDMA_STATE_ACTIVE) {
 895                 spin_unlock_irqrestore(&chan->lock, flags);
 896                 return -EINVAL;
 897         }
 898
 899         chan->state = CPDMA_STATE_TEARDOWN;
 900         dma_reg_write(ctlr, chan->int_clear, chan->mask);
 901
 902         /* trigger teardown */
 903         dma_reg_write(ctlr, chan->td, chan_linear(chan));
 904
 905         /* wait for teardown complete */
 906         timeout = 100 * 100; /* 100 ms */
 907         while (timeout) {
 908                 u32 cp = chan_read(chan, cp);
 909                 if ((cp & CPDMA_TEARDOWN_VALUE) == CPDMA_TEARDOWN_VALUE)
 910                         break;
 911                 udelay(10);
 912                 timeout--;
 913         }
 914         WARN_ON(!timeout);
 915         chan_write(chan, cp, CPDMA_TEARDOWN_VALUE);
 916
 917         /* handle completed packets */
 918         spin_unlock_irqrestore(&chan->lock, flags);
 919         do {
 920                 ret = __cpdma_chan_process(chan);
 921                 if (ret < 0)
 922                         break;
 923         } while ((ret & CPDMA_DESC_TD_COMPLETE) == 0);
 924         spin_lock_irqsave(&chan->lock, flags);
 925
 926         /* remaining packets haven't been tx/rx'ed, clean them up */
 927         while (chan->head) {
 928                 struct cpdma_desc __iomem *desc = chan->head;
 929                 dma_addr_t next_dma;
 930
 931                 next_dma = desc_read(desc, hw_next);
 932                 chan->head = desc_from_phys(pool, next_dma);
 933                 chan->count--;
 934                 chan->stats.teardown_dequeue++;
 935
 936                 /* issue callback without locks held */
 937                 spin_unlock_irqrestore(&chan->lock, flags);
 938                 __cpdma_chan_free(chan, desc, 0, -ENOSYS);
 939                 spin_lock_irqsave(&chan->lock, flags);
 940         }
 941
 942         chan->state = CPDMA_STATE_IDLE;
 943         spin_unlock_irqrestore(&chan->lock, flags);
 944         return 0;
 945 }
 946 EXPORT_SYMBOL_GPL(cpdma_chan_stop);
 947
 948 int cpdma_chan_int_ctrl(struct cpdma_chan *chan, bool enable)
 949 {
 950         unsigned long flags;
 951
 952         spin_lock_irqsave(&chan->lock, flags);
 953         if (chan->state != CPDMA_STATE_ACTIVE) {
 954                 spin_unlock_irqrestore(&chan->lock, flags);
 955                 return -EINVAL;
 956         }
 957
 958         dma_reg_write(chan->ctlr, enable ? chan->int_set : chan->int_clear,
 959                       chan->mask);
 960         spin_unlock_irqrestore(&chan->lock, flags);
 961
 962         return 0;
 963 }
 964
 965 struct cpdma_control_info {
 966         u32             reg;
 967         u32             shift, mask;
 968         int             access;
 969 #define ACCESS_RO       BIT(0)
 970 #define ACCESS_WO       BIT(1)
 971 #define ACCESS_RW       (ACCESS_RO | ACCESS_WO)
 972 };
 973
 974 static struct cpdma_control_info controls[] = {
 975         [CPDMA_CMD_IDLE]          = {CPDMA_DMACONTROL,  3,  1,      ACCESS_WO},
 976         [CPDMA_COPY_ERROR_FRAMES] = {CPDMA_DMACONTROL,  4,  1,      ACCESS_RW},
 977         [CPDMA_RX_OFF_LEN_UPDATE] = {CPDMA_DMACONTROL,  2,  1,      ACCESS_RW},
 978         [CPDMA_RX_OWNERSHIP_FLIP] = {CPDMA_DMACONTROL,  1,  1,      ACCESS_RW},
 979         [CPDMA_TX_PRIO_FIXED]     = {CPDMA_DMACONTROL,  0,  1,      ACCESS_RW},
 980         [CPDMA_STAT_IDLE]         = {CPDMA_DMASTATUS,   31, 1,      ACCESS_RO},
 981         [CPDMA_STAT_TX_ERR_CODE]  = {CPDMA_DMASTATUS,   20, 0xf,    ACCESS_RW},
 982         [CPDMA_STAT_TX_ERR_CHAN]  = {CPDMA_DMASTATUS,   16, 0x7,    ACCESS_RW},
 983         [CPDMA_STAT_RX_ERR_CODE]  = {CPDMA_DMASTATUS,   12, 0xf,    ACCESS_RW},
 984         [CPDMA_STAT_RX_ERR_CHAN]  = {CPDMA_DMASTATUS,   8,  0x7,    ACCESS_RW},
 985         [CPDMA_RX_BUFFER_OFFSET]  = {CPDMA_RXBUFFOFS,   0,  0xffff, ACCESS_RW},
 986 };
 987
 988 int cpdma_control_get(struct cpdma_ctlr *ctlr, int control)
 989 {
 990         unsigned long flags;
 991         struct cpdma_control_info *info = &controls[control];
 992         int ret;
 993
 994         spin_lock_irqsave(&ctlr->lock, flags);
 995
 996         ret = -ENOTSUPP;
 997         if (!ctlr->params.has_ext_regs)
 998                 goto unlock_ret;
 999
1000         ret = -EINVAL;
1001         if (ctlr->state != CPDMA_STATE_ACTIVE)
1002                 goto unlock_ret;
1003
1004         ret = -ENOENT;
1005         if (control < 0 || control >= ARRAY_SIZE(controls))
1006                 goto unlock_ret;
1007
1008         ret = -EPERM;
1009         if ((info->access & ACCESS_RO) != ACCESS_RO)
1010                 goto unlock_ret;
1011
1012         ret = (dma_reg_read(ctlr, info->reg) >> info->shift) & info->mask;
1013
1014 unlock_ret:
1015         spin_unlock_irqrestore(&ctlr->lock, flags);
1016         return ret;
1017 }
1018
1019 int cpdma_control_set(struct cpdma_ctlr *ctlr, int control, int value)
1020 {
1021         unsigned long flags;
1022         struct cpdma_control_info *info = &controls[control];
1023         int ret;
1024         u32 val;
1025
1026         spin_lock_irqsave(&ctlr->lock, flags);
1027
1028         ret = -ENOTSUPP;
1029         if (!ctlr->params.has_ext_regs)
1030                 goto unlock_ret;
1031
1032         ret = -EINVAL;
1033         if (ctlr->state != CPDMA_STATE_ACTIVE)
1034                 goto unlock_ret;
1035
1036         ret = -ENOENT;
1037         if (control < 0 || control >= ARRAY_SIZE(controls))
1038                 goto unlock_ret;
1039
1040         ret = -EPERM;
1041         if ((info->access & ACCESS_WO) != ACCESS_WO)
1042                 goto unlock_ret;
1043
1044         val  = dma_reg_read(ctlr, info->reg);
1045         val &= ~(info->mask << info->shift);
1046         val |= (value & info->mask) << info->shift;
1047         dma_reg_write(ctlr, info->reg, val);
1048         ret = 0;
1049
1050 unlock_ret:
1051         spin_unlock_irqrestore(&ctlr->lock, flags);
1052         return ret;
1053 }
1054 EXPORT_SYMBOL_GPL(cpdma_control_set);
1055
1056 MODULE_LICENSE("GPL");