git.oblomov.eu Git - linux-2.6/blob - drivers/dma/fsldma.c

   1 /*
   2  * Freescale MPC85xx, MPC83xx DMA Engine support
   3  *
   4  * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
   5  *
   6  * Author:
   7  *   Zhang Wei <wei.zhang@freescale.com>, Jul 2007
   8  *   Ebony Zhu <ebony.zhu@freescale.com>, May 2007
   9  *
  10  * Description:
  11  *   DMA engine driver for Freescale MPC8540 DMA controller, which is
  12  *   also fit for MPC8560, MPC8555, MPC8548, MPC8641, and etc.
  13  *   The support for MPC8349 DMA contorller is also added.
  14  *
  15  * This is free software; you can redistribute it and/or modify
  16  * it under the terms of the GNU General Public License as published by
  17  * the Free Software Foundation; either version 2 of the License, or
  18  * (at your option) any later version.
  19  *
  20  */
  21
  22 #include <linux/init.h>
  23 #include <linux/module.h>
  24 #include <linux/pci.h>
  25 #include <linux/interrupt.h>
  26 #include <linux/dmaengine.h>
  27 #include <linux/delay.h>
  28 #include <linux/dma-mapping.h>
  29 #include <linux/dmapool.h>
  30 #include <linux/of_platform.h>
  31
  32 #include "fsldma.h"
  33
  34 static void dma_init(struct fsl_dma_chan *fsl_chan)
  35 {
  36         /* Reset the channel */
  37         DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, 0, 32);
  38
  39         switch (fsl_chan->feature & FSL_DMA_IP_MASK) {
  40         case FSL_DMA_IP_85XX:
  41                 /* Set the channel to below modes:
  42                  * EIE - Error interrupt enable
  43                  * EOSIE - End of segments interrupt enable (basic mode)
  44                  * EOLNIE - End of links interrupt enable
  45                  */
  46                 DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, FSL_DMA_MR_EIE
  47                                 | FSL_DMA_MR_EOLNIE | FSL_DMA_MR_EOSIE, 32);
  48                 break;
  49         case FSL_DMA_IP_83XX:
  50                 /* Set the channel to below modes:
  51                  * EOTIE - End-of-transfer interrupt enable
  52                  */
  53                 DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, FSL_DMA_MR_EOTIE,
  54                                 32);
  55                 break;
  56         }
  57
  58 }
  59
  60 static void set_sr(struct fsl_dma_chan *fsl_chan, dma_addr_t val)
  61 {
  62         DMA_OUT(fsl_chan, &fsl_chan->reg_base->sr, val, 32);
  63 }
  64
  65 static dma_addr_t get_sr(struct fsl_dma_chan *fsl_chan)
  66 {
  67         return DMA_IN(fsl_chan, &fsl_chan->reg_base->sr, 32);
  68 }
  69
  70 static void set_desc_cnt(struct fsl_dma_chan *fsl_chan,
  71                                 struct fsl_dma_ld_hw *hw, u32 count)
  72 {
  73         hw->count = CPU_TO_DMA(fsl_chan, count, 32);
  74 }
  75
  76 static void set_desc_src(struct fsl_dma_chan *fsl_chan,
  77                                 struct fsl_dma_ld_hw *hw, dma_addr_t src)
  78 {
  79         u64 snoop_bits;
  80
  81         snoop_bits = ((fsl_chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX)
  82                 ? ((u64)FSL_DMA_SATR_SREADTYPE_SNOOP_READ << 32) : 0;
  83         hw->src_addr = CPU_TO_DMA(fsl_chan, snoop_bits | src, 64);
  84 }
  85
  86 static void set_desc_dest(struct fsl_dma_chan *fsl_chan,
  87                                 struct fsl_dma_ld_hw *hw, dma_addr_t dest)
  88 {
  89         u64 snoop_bits;
  90
  91         snoop_bits = ((fsl_chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX)
  92                 ? ((u64)FSL_DMA_DATR_DWRITETYPE_SNOOP_WRITE << 32) : 0;
  93         hw->dst_addr = CPU_TO_DMA(fsl_chan, snoop_bits | dest, 64);
  94 }
  95
  96 static void set_desc_next(struct fsl_dma_chan *fsl_chan,
  97                                 struct fsl_dma_ld_hw *hw, dma_addr_t next)
  98 {
  99         u64 snoop_bits;
 100
 101         snoop_bits = ((fsl_chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_83XX)
 102                 ? FSL_DMA_SNEN : 0;
 103         hw->next_ln_addr = CPU_TO_DMA(fsl_chan, snoop_bits | next, 64);
 104 }
 105
 106 static void set_cdar(struct fsl_dma_chan *fsl_chan, dma_addr_t addr)
 107 {
 108         DMA_OUT(fsl_chan, &fsl_chan->reg_base->cdar, addr | FSL_DMA_SNEN, 64);
 109 }
 110
 111 static dma_addr_t get_cdar(struct fsl_dma_chan *fsl_chan)
 112 {
 113         return DMA_IN(fsl_chan, &fsl_chan->reg_base->cdar, 64) & ~FSL_DMA_SNEN;
 114 }
 115
 116 static void set_ndar(struct fsl_dma_chan *fsl_chan, dma_addr_t addr)
 117 {
 118         DMA_OUT(fsl_chan, &fsl_chan->reg_base->ndar, addr, 64);
 119 }
 120
 121 static dma_addr_t get_ndar(struct fsl_dma_chan *fsl_chan)
 122 {
 123         return DMA_IN(fsl_chan, &fsl_chan->reg_base->ndar, 64);
 124 }
 125
 126 static int dma_is_idle(struct fsl_dma_chan *fsl_chan)
 127 {
 128         u32 sr = get_sr(fsl_chan);
 129         return (!(sr & FSL_DMA_SR_CB)) || (sr & FSL_DMA_SR_CH);
 130 }
 131
 132 static void dma_start(struct fsl_dma_chan *fsl_chan)
 133 {
 134         u32 mr_set = 0;;
 135
 136         if (fsl_chan->feature & FSL_DMA_CHAN_PAUSE_EXT) {
 137                 DMA_OUT(fsl_chan, &fsl_chan->reg_base->bcr, 0, 32);
 138                 mr_set |= FSL_DMA_MR_EMP_EN;
 139         } else
 140                 DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
 141                         DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
 142                                 & ~FSL_DMA_MR_EMP_EN, 32);
 143
 144         if (fsl_chan->feature & FSL_DMA_CHAN_START_EXT)
 145                 mr_set |= FSL_DMA_MR_EMS_EN;
 146         else
 147                 mr_set |= FSL_DMA_MR_CS;
 148
 149         DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
 150                         DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
 151                         | mr_set, 32);
 152 }
 153
 154 static void dma_halt(struct fsl_dma_chan *fsl_chan)
 155 {
 156         int i = 0;
 157         DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
 158                 DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) | FSL_DMA_MR_CA,
 159                 32);
 160         DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
 161                 DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) & ~(FSL_DMA_MR_CS
 162                 | FSL_DMA_MR_EMS_EN | FSL_DMA_MR_CA), 32);
 163
 164         while (!dma_is_idle(fsl_chan) && (i++ < 100))
 165                 udelay(10);
 166         if (i >= 100 && !dma_is_idle(fsl_chan))
 167                 dev_err(fsl_chan->dev, "DMA halt timeout!\n");
 168 }
 169
 170 static void set_ld_eol(struct fsl_dma_chan *fsl_chan,
 171                         struct fsl_desc_sw *desc)
 172 {
 173         desc->hw.next_ln_addr = CPU_TO_DMA(fsl_chan,
 174                 DMA_TO_CPU(fsl_chan, desc->hw.next_ln_addr, 64) | FSL_DMA_EOL,
 175                 64);
 176 }
 177
 178 static void append_ld_queue(struct fsl_dma_chan *fsl_chan,
 179                 struct fsl_desc_sw *new_desc)
 180 {
 181         struct fsl_desc_sw *queue_tail = to_fsl_desc(fsl_chan->ld_queue.prev);
 182
 183         if (list_empty(&fsl_chan->ld_queue))
 184                 return;
 185
 186         /* Link to the new descriptor physical address and
 187          * Enable End-of-segment interrupt for
 188          * the last link descriptor.
 189          * (the previous node's next link descriptor)
 190          *
 191          * For FSL_DMA_IP_83xx, the snoop enable bit need be set.
 192          */
 193         queue_tail->hw.next_ln_addr = CPU_TO_DMA(fsl_chan,
 194                         new_desc->async_tx.phys | FSL_DMA_EOSIE |
 195                         (((fsl_chan->feature & FSL_DMA_IP_MASK)
 196                                 == FSL_DMA_IP_83XX) ? FSL_DMA_SNEN : 0), 64);
 197 }
 198
 199 /**
 200  * fsl_chan_set_src_loop_size - Set source address hold transfer size
 201  * @fsl_chan : Freescale DMA channel
 202  * @size     : Address loop size, 0 for disable loop
 203  *
 204  * The set source address hold transfer size. The source
 205  * address hold or loop transfer size is when the DMA transfer
 206  * data from source address (SA), if the loop size is 4, the DMA will
 207  * read data from SA, SA + 1, SA + 2, SA + 3, then loop back to SA,
 208  * SA + 1 ... and so on.
 209  */
 210 static void fsl_chan_set_src_loop_size(struct fsl_dma_chan *fsl_chan, int size)
 211 {
 212         switch (size) {
 213         case 0:
 214                 DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
 215                         DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) &
 216                         (~FSL_DMA_MR_SAHE), 32);
 217                 break;
 218         case 1:
 219         case 2:
 220         case 4:
 221         case 8:
 222                 DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
 223                         DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) |
 224                         FSL_DMA_MR_SAHE | (__ilog2(size) << 14),
 225                         32);
 226                 break;
 227         }
 228 }
 229
 230 /**
 231  * fsl_chan_set_dest_loop_size - Set destination address hold transfer size
 232  * @fsl_chan : Freescale DMA channel
 233  * @size     : Address loop size, 0 for disable loop
 234  *
 235  * The set destination address hold transfer size. The destination
 236  * address hold or loop transfer size is when the DMA transfer
 237  * data to destination address (TA), if the loop size is 4, the DMA will
 238  * write data to TA, TA + 1, TA + 2, TA + 3, then loop back to TA,
 239  * TA + 1 ... and so on.
 240  */
 241 static void fsl_chan_set_dest_loop_size(struct fsl_dma_chan *fsl_chan, int size)
 242 {
 243         switch (size) {
 244         case 0:
 245                 DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
 246                         DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) &
 247                         (~FSL_DMA_MR_DAHE), 32);
 248                 break;
 249         case 1:
 250         case 2:
 251         case 4:
 252         case 8:
 253                 DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
 254                         DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) |
 255                         FSL_DMA_MR_DAHE | (__ilog2(size) << 16),
 256                         32);
 257                 break;
 258         }
 259 }
 260
 261 /**
 262  * fsl_chan_toggle_ext_pause - Toggle channel external pause status
 263  * @fsl_chan : Freescale DMA channel
 264  * @size     : Pause control size, 0 for disable external pause control.
 265  *             The maximum is 1024.
 266  *
 267  * The Freescale DMA channel can be controlled by the external
 268  * signal DREQ#. The pause control size is how many bytes are allowed
 269  * to transfer before pausing the channel, after which a new assertion
 270  * of DREQ# resumes channel operation.
 271  */
 272 static void fsl_chan_toggle_ext_pause(struct fsl_dma_chan *fsl_chan, int size)
 273 {
 274         if (size > 1024)
 275                 return;
 276
 277         if (size) {
 278                 DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
 279                         DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
 280                                 | ((__ilog2(size) << 24) & 0x0f000000),
 281                         32);
 282                 fsl_chan->feature |= FSL_DMA_CHAN_PAUSE_EXT;
 283         } else
 284                 fsl_chan->feature &= ~FSL_DMA_CHAN_PAUSE_EXT;
 285 }
 286
 287 /**
 288  * fsl_chan_toggle_ext_start - Toggle channel external start status
 289  * @fsl_chan : Freescale DMA channel
 290  * @enable   : 0 is disabled, 1 is enabled.
 291  *
 292  * If enable the external start, the channel can be started by an
 293  * external DMA start pin. So the dma_start() does not start the
 294  * transfer immediately. The DMA channel will wait for the
 295  * control pin asserted.
 296  */
 297 static void fsl_chan_toggle_ext_start(struct fsl_dma_chan *fsl_chan, int enable)
 298 {
 299         if (enable)
 300                 fsl_chan->feature |= FSL_DMA_CHAN_START_EXT;
 301         else
 302                 fsl_chan->feature &= ~FSL_DMA_CHAN_START_EXT;
 303 }
 304
 305 static dma_cookie_t fsl_dma_tx_submit(struct dma_async_tx_descriptor *tx)
 306 {
 307         struct fsl_desc_sw *desc = tx_to_fsl_desc(tx);
 308         struct fsl_dma_chan *fsl_chan = to_fsl_chan(tx->chan);
 309         unsigned long flags;
 310         dma_cookie_t cookie;
 311
 312         /* cookie increment and adding to ld_queue must be atomic */
 313         spin_lock_irqsave(&fsl_chan->desc_lock, flags);
 314
 315         cookie = fsl_chan->common.cookie;
 316         cookie++;
 317         if (cookie < 0)
 318                 cookie = 1;
 319         desc->async_tx.cookie = cookie;
 320         fsl_chan->common.cookie = desc->async_tx.cookie;
 321
 322         append_ld_queue(fsl_chan, desc);
 323         list_splice_init(&desc->async_tx.tx_list, fsl_chan->ld_queue.prev);
 324
 325         spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
 326
 327         return cookie;
 328 }
 329
 330 /**
 331  * fsl_dma_alloc_descriptor - Allocate descriptor from channel's DMA pool.
 332  * @fsl_chan : Freescale DMA channel
 333  *
 334  * Return - The descriptor allocated. NULL for failed.
 335  */
 336 static struct fsl_desc_sw *fsl_dma_alloc_descriptor(
 337                                         struct fsl_dma_chan *fsl_chan)
 338 {
 339         dma_addr_t pdesc;
 340         struct fsl_desc_sw *desc_sw;
 341
 342         desc_sw = dma_pool_alloc(fsl_chan->desc_pool, GFP_ATOMIC, &pdesc);
 343         if (desc_sw) {
 344                 memset(desc_sw, 0, sizeof(struct fsl_desc_sw));
 345                 dma_async_tx_descriptor_init(&desc_sw->async_tx,
 346                                                 &fsl_chan->common);
 347                 desc_sw->async_tx.tx_submit = fsl_dma_tx_submit;
 348                 INIT_LIST_HEAD(&desc_sw->async_tx.tx_list);
 349                 desc_sw->async_tx.phys = pdesc;
 350         }
 351
 352         return desc_sw;
 353 }
 354
 355
 356 /**
 357  * fsl_dma_alloc_chan_resources - Allocate resources for DMA channel.
 358  * @fsl_chan : Freescale DMA channel
 359  *
 360  * This function will create a dma pool for descriptor allocation.
 361  *
 362  * Return - The number of descriptors allocated.
 363  */
 364 static int fsl_dma_alloc_chan_resources(struct dma_chan *chan)
 365 {
 366         struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
 367         LIST_HEAD(tmp_list);
 368
 369         /* We need the descriptor to be aligned to 32bytes
 370          * for meeting FSL DMA specification requirement.
 371          */
 372         fsl_chan->desc_pool = dma_pool_create("fsl_dma_engine_desc_pool",
 373                         fsl_chan->dev, sizeof(struct fsl_desc_sw),
 374                         32, 0);
 375         if (!fsl_chan->desc_pool) {
 376                 dev_err(fsl_chan->dev, "No memory for channel %d "
 377                         "descriptor dma pool.\n", fsl_chan->id);
 378                 return 0;
 379         }
 380
 381         return 1;
 382 }
 383
 384 /**
 385  * fsl_dma_free_chan_resources - Free all resources of the channel.
 386  * @fsl_chan : Freescale DMA channel
 387  */
 388 static void fsl_dma_free_chan_resources(struct dma_chan *chan)
 389 {
 390         struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
 391         struct fsl_desc_sw *desc, *_desc;
 392         unsigned long flags;
 393
 394         dev_dbg(fsl_chan->dev, "Free all channel resources.\n");
 395         spin_lock_irqsave(&fsl_chan->desc_lock, flags);
 396         list_for_each_entry_safe(desc, _desc, &fsl_chan->ld_queue, node) {
 397 #ifdef FSL_DMA_LD_DEBUG
 398                 dev_dbg(fsl_chan->dev,
 399                                 "LD %p will be released.\n", desc);
 400 #endif
 401                 list_del(&desc->node);
 402                 /* free link descriptor */
 403                 dma_pool_free(fsl_chan->desc_pool, desc, desc->async_tx.phys);
 404         }
 405         spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
 406         dma_pool_destroy(fsl_chan->desc_pool);
 407 }
 408
 409 static struct dma_async_tx_descriptor *fsl_dma_prep_memcpy(
 410         struct dma_chan *chan, dma_addr_t dma_dest, dma_addr_t dma_src,
 411         size_t len, unsigned long flags)
 412 {
 413         struct fsl_dma_chan *fsl_chan;
 414         struct fsl_desc_sw *first = NULL, *prev = NULL, *new;
 415         size_t copy;
 416         LIST_HEAD(link_chain);
 417
 418         if (!chan)
 419                 return NULL;
 420
 421         if (!len)
 422                 return NULL;
 423
 424         fsl_chan = to_fsl_chan(chan);
 425
 426         do {
 427
 428                 /* Allocate the link descriptor from DMA pool */
 429                 new = fsl_dma_alloc_descriptor(fsl_chan);
 430                 if (!new) {
 431                         dev_err(fsl_chan->dev,
 432                                         "No free memory for link descriptor\n");
 433                         return NULL;
 434                 }
 435 #ifdef FSL_DMA_LD_DEBUG
 436                 dev_dbg(fsl_chan->dev, "new link desc alloc %p\n", new);
 437 #endif
 438
 439                 copy = min(len, FSL_DMA_BCR_MAX_CNT);
 440
 441                 set_desc_cnt(fsl_chan, &new->hw, copy);
 442                 set_desc_src(fsl_chan, &new->hw, dma_src);
 443                 set_desc_dest(fsl_chan, &new->hw, dma_dest);
 444
 445                 if (!first)
 446                         first = new;
 447                 else
 448                         set_desc_next(fsl_chan, &prev->hw, new->async_tx.phys);
 449
 450                 new->async_tx.cookie = 0;
 451                 new->async_tx.ack = 1;
 452
 453                 prev = new;
 454                 len -= copy;
 455                 dma_src += copy;
 456                 dma_dest += copy;
 457
 458                 /* Insert the link descriptor to the LD ring */
 459                 list_add_tail(&new->node, &first->async_tx.tx_list);
 460         } while (len);
 461
 462         new->async_tx.ack = 0; /* client is in control of this ack */
 463         new->async_tx.cookie = -EBUSY;
 464
 465         /* Set End-of-link to the last link descriptor of new list*/
 466         set_ld_eol(fsl_chan, new);
 467
 468         return first ? &first->async_tx : NULL;
 469 }
 470
 471 /**
 472  * fsl_dma_update_completed_cookie - Update the completed cookie.
 473  * @fsl_chan : Freescale DMA channel
 474  */
 475 static void fsl_dma_update_completed_cookie(struct fsl_dma_chan *fsl_chan)
 476 {
 477         struct fsl_desc_sw *cur_desc, *desc;
 478         dma_addr_t ld_phy;
 479
 480         ld_phy = get_cdar(fsl_chan) & FSL_DMA_NLDA_MASK;
 481
 482         if (ld_phy) {
 483                 cur_desc = NULL;
 484                 list_for_each_entry(desc, &fsl_chan->ld_queue, node)
 485                         if (desc->async_tx.phys == ld_phy) {
 486                                 cur_desc = desc;
 487                                 break;
 488                         }
 489
 490                 if (cur_desc && cur_desc->async_tx.cookie) {
 491                         if (dma_is_idle(fsl_chan))
 492                                 fsl_chan->completed_cookie =
 493                                         cur_desc->async_tx.cookie;
 494                         else
 495                                 fsl_chan->completed_cookie =
 496                                         cur_desc->async_tx.cookie - 1;
 497                 }
 498         }
 499 }
 500
 501 /**
 502  * fsl_chan_ld_cleanup - Clean up link descriptors
 503  * @fsl_chan : Freescale DMA channel
 504  *
 505  * This function clean up the ld_queue of DMA channel.
 506  * If 'in_intr' is set, the function will move the link descriptor to
 507  * the recycle list. Otherwise, free it directly.
 508  */
 509 static void fsl_chan_ld_cleanup(struct fsl_dma_chan *fsl_chan)
 510 {
 511         struct fsl_desc_sw *desc, *_desc;
 512         unsigned long flags;
 513
 514         spin_lock_irqsave(&fsl_chan->desc_lock, flags);
 515
 516         fsl_dma_update_completed_cookie(fsl_chan);
 517         dev_dbg(fsl_chan->dev, "chan completed_cookie = %d\n",
 518                         fsl_chan->completed_cookie);
 519         list_for_each_entry_safe(desc, _desc, &fsl_chan->ld_queue, node) {
 520                 dma_async_tx_callback callback;
 521                 void *callback_param;
 522
 523                 if (dma_async_is_complete(desc->async_tx.cookie,
 524                             fsl_chan->completed_cookie, fsl_chan->common.cookie)
 525                                 == DMA_IN_PROGRESS)
 526                         break;
 527
 528                 callback = desc->async_tx.callback;
 529                 callback_param = desc->async_tx.callback_param;
 530
 531                 /* Remove from ld_queue list */
 532                 list_del(&desc->node);
 533
 534                 dev_dbg(fsl_chan->dev, "link descriptor %p will be recycle.\n",
 535                                 desc);
 536                 dma_pool_free(fsl_chan->desc_pool, desc, desc->async_tx.phys);
 537
 538                 /* Run the link descriptor callback function */
 539                 if (callback) {
 540                         spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
 541                         dev_dbg(fsl_chan->dev, "link descriptor %p callback\n",
 542                                         desc);
 543                         callback(callback_param);
 544                         spin_lock_irqsave(&fsl_chan->desc_lock, flags);
 545                 }
 546         }
 547         spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
 548 }
 549
 550 /**
 551  * fsl_chan_xfer_ld_queue - Transfer link descriptors in channel ld_queue.
 552  * @fsl_chan : Freescale DMA channel
 553  */
 554 static void fsl_chan_xfer_ld_queue(struct fsl_dma_chan *fsl_chan)
 555 {
 556         struct list_head *ld_node;
 557         dma_addr_t next_dest_addr;
 558         unsigned long flags;
 559
 560         if (!dma_is_idle(fsl_chan))
 561                 return;
 562
 563         dma_halt(fsl_chan);
 564
 565         /* If there are some link descriptors
 566          * not transfered in queue. We need to start it.
 567          */
 568         spin_lock_irqsave(&fsl_chan->desc_lock, flags);
 569
 570         /* Find the first un-transfer desciptor */
 571         for (ld_node = fsl_chan->ld_queue.next;
 572                 (ld_node != &fsl_chan->ld_queue)
 573                         && (dma_async_is_complete(
 574                                 to_fsl_desc(ld_node)->async_tx.cookie,
 575                                 fsl_chan->completed_cookie,
 576                                 fsl_chan->common.cookie) == DMA_SUCCESS);
 577                 ld_node = ld_node->next);
 578
 579         spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
 580
 581         if (ld_node != &fsl_chan->ld_queue) {
 582                 /* Get the ld start address from ld_queue */
 583                 next_dest_addr = to_fsl_desc(ld_node)->async_tx.phys;
 584                 dev_dbg(fsl_chan->dev, "xfer LDs staring from 0x%016llx\n",
 585                                 (u64)next_dest_addr);
 586                 set_cdar(fsl_chan, next_dest_addr);
 587                 dma_start(fsl_chan);
 588         } else {
 589                 set_cdar(fsl_chan, 0);
 590                 set_ndar(fsl_chan, 0);
 591         }
 592 }
 593
 594 /**
 595  * fsl_dma_memcpy_issue_pending - Issue the DMA start command
 596  * @fsl_chan : Freescale DMA channel
 597  */
 598 static void fsl_dma_memcpy_issue_pending(struct dma_chan *chan)
 599 {
 600         struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
 601
 602 #ifdef FSL_DMA_LD_DEBUG
 603         struct fsl_desc_sw *ld;
 604         unsigned long flags;
 605
 606         spin_lock_irqsave(&fsl_chan->desc_lock, flags);
 607         if (list_empty(&fsl_chan->ld_queue)) {
 608                 spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
 609                 return;
 610         }
 611
 612         dev_dbg(fsl_chan->dev, "--memcpy issue--\n");
 613         list_for_each_entry(ld, &fsl_chan->ld_queue, node) {
 614                 int i;
 615                 dev_dbg(fsl_chan->dev, "Ch %d, LD %08x\n",
 616                                 fsl_chan->id, ld->async_tx.phys);
 617                 for (i = 0; i < 8; i++)
 618                         dev_dbg(fsl_chan->dev, "LD offset %d: %08x\n",
 619                                         i, *(((u32 *)&ld->hw) + i));
 620         }
 621         dev_dbg(fsl_chan->dev, "----------------\n");
 622         spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
 623 #endif
 624
 625         fsl_chan_xfer_ld_queue(fsl_chan);
 626 }
 627
 628 static void fsl_dma_dependency_added(struct dma_chan *chan)
 629 {
 630         struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
 631
 632         fsl_chan_ld_cleanup(fsl_chan);
 633 }
 634
 635 /**
 636  * fsl_dma_is_complete - Determine the DMA status
 637  * @fsl_chan : Freescale DMA channel
 638  */
 639 static enum dma_status fsl_dma_is_complete(struct dma_chan *chan,
 640                                         dma_cookie_t cookie,
 641                                         dma_cookie_t *done,
 642                                         dma_cookie_t *used)
 643 {
 644         struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
 645         dma_cookie_t last_used;
 646         dma_cookie_t last_complete;
 647
 648         fsl_chan_ld_cleanup(fsl_chan);
 649
 650         last_used = chan->cookie;
 651         last_complete = fsl_chan->completed_cookie;
 652
 653         if (done)
 654                 *done = last_complete;
 655
 656         if (used)
 657                 *used = last_used;
 658
 659         return dma_async_is_complete(cookie, last_complete, last_used);
 660 }
 661
 662 static irqreturn_t fsl_dma_chan_do_interrupt(int irq, void *data)
 663 {
 664         struct fsl_dma_chan *fsl_chan = (struct fsl_dma_chan *)data;
 665         dma_addr_t stat;
 666
 667         stat = get_sr(fsl_chan);
 668         dev_dbg(fsl_chan->dev, "event: channel %d, stat = 0x%x\n",
 669                                                 fsl_chan->id, stat);
 670         set_sr(fsl_chan, stat);         /* Clear the event register */
 671
 672         stat &= ~(FSL_DMA_SR_CB | FSL_DMA_SR_CH);
 673         if (!stat)
 674                 return IRQ_NONE;
 675
 676         if (stat & FSL_DMA_SR_TE)
 677                 dev_err(fsl_chan->dev, "Transfer Error!\n");
 678
 679         /* If the link descriptor segment transfer finishes,
 680          * we will recycle the used descriptor.
 681          */
 682         if (stat & FSL_DMA_SR_EOSI) {
 683                 dev_dbg(fsl_chan->dev, "event: End-of-segments INT\n");
 684                 dev_dbg(fsl_chan->dev, "event: clndar 0x%016llx, "
 685                                 "nlndar 0x%016llx\n", (u64)get_cdar(fsl_chan),
 686                                 (u64)get_ndar(fsl_chan));
 687                 stat &= ~FSL_DMA_SR_EOSI;
 688         }
 689
 690         /* If it current transfer is the end-of-transfer,
 691          * we should clear the Channel Start bit for
 692          * prepare next transfer.
 693          */
 694         if (stat & (FSL_DMA_SR_EOLNI | FSL_DMA_SR_EOCDI)) {
 695                 dev_dbg(fsl_chan->dev, "event: End-of-link INT\n");
 696                 stat &= ~FSL_DMA_SR_EOLNI;
 697                 fsl_chan_xfer_ld_queue(fsl_chan);
 698         }
 699
 700         if (stat)
 701                 dev_dbg(fsl_chan->dev, "event: unhandled sr 0x%02x\n",
 702                                         stat);
 703
 704         dev_dbg(fsl_chan->dev, "event: Exit\n");
 705         tasklet_schedule(&fsl_chan->tasklet);
 706         return IRQ_HANDLED;
 707 }
 708
 709 static irqreturn_t fsl_dma_do_interrupt(int irq, void *data)
 710 {
 711         struct fsl_dma_device *fdev = (struct fsl_dma_device *)data;
 712         u32 gsr;
 713         int ch_nr;
 714
 715         gsr = (fdev->feature & FSL_DMA_BIG_ENDIAN) ? in_be32(fdev->reg_base)
 716                         : in_le32(fdev->reg_base);
 717         ch_nr = (32 - ffs(gsr)) / 8;
 718
 719         return fdev->chan[ch_nr] ? fsl_dma_chan_do_interrupt(irq,
 720                         fdev->chan[ch_nr]) : IRQ_NONE;
 721 }
 722
 723 static void dma_do_tasklet(unsigned long data)
 724 {
 725         struct fsl_dma_chan *fsl_chan = (struct fsl_dma_chan *)data;
 726         fsl_chan_ld_cleanup(fsl_chan);
 727 }
 728
 729 static void fsl_dma_callback_test(struct fsl_dma_chan *fsl_chan)
 730 {
 731         if (fsl_chan)
 732                 dev_info(fsl_chan->dev, "selftest: callback is ok!\n");
 733 }
 734
 735 static int fsl_dma_self_test(struct fsl_dma_chan *fsl_chan)
 736 {
 737         struct dma_chan *chan;
 738         int err = 0;
 739         dma_addr_t dma_dest, dma_src;
 740         dma_cookie_t cookie;
 741         u8 *src, *dest;
 742         int i;
 743         size_t test_size;
 744         struct dma_async_tx_descriptor *tx1, *tx2, *tx3;
 745
 746         test_size = 4096;
 747
 748         src = kmalloc(test_size * 2, GFP_KERNEL);
 749         if (!src) {
 750                 dev_err(fsl_chan->dev,
 751                                 "selftest: Cannot alloc memory for test!\n");
 752                 err = -ENOMEM;
 753                 goto out;
 754         }
 755
 756         dest = src + test_size;
 757
 758         for (i = 0; i < test_size; i++)
 759                 src[i] = (u8) i;
 760
 761         chan = &fsl_chan->common;
 762
 763         if (fsl_dma_alloc_chan_resources(chan) < 1) {
 764                 dev_err(fsl_chan->dev,
 765                                 "selftest: Cannot alloc resources for DMA\n");
 766                 err = -ENODEV;
 767                 goto out;
 768         }
 769
 770         /* TX 1 */
 771         dma_src = dma_map_single(fsl_chan->dev, src, test_size / 2,
 772                                  DMA_TO_DEVICE);
 773         dma_dest = dma_map_single(fsl_chan->dev, dest, test_size / 2,
 774                                   DMA_FROM_DEVICE);
 775         tx1 = fsl_dma_prep_memcpy(chan, dma_dest, dma_src, test_size / 2, 0);
 776         async_tx_ack(tx1);
 777
 778         cookie = fsl_dma_tx_submit(tx1);
 779         fsl_dma_memcpy_issue_pending(chan);
 780         msleep(2);
 781
 782         if (fsl_dma_is_complete(chan, cookie, NULL, NULL) != DMA_SUCCESS) {
 783                 dev_err(fsl_chan->dev, "selftest: Time out!\n");
 784                 err = -ENODEV;
 785                 goto out;
 786         }
 787
 788         /* Test free and re-alloc channel resources */
 789         fsl_dma_free_chan_resources(chan);
 790
 791         if (fsl_dma_alloc_chan_resources(chan) < 1) {
 792                 dev_err(fsl_chan->dev,
 793                                 "selftest: Cannot alloc resources for DMA\n");
 794                 err = -ENODEV;
 795                 goto free_resources;
 796         }
 797
 798         /* Continue to test
 799          * TX 2
 800          */
 801         dma_src = dma_map_single(fsl_chan->dev, src + test_size / 2,
 802                                         test_size / 4, DMA_TO_DEVICE);
 803         dma_dest = dma_map_single(fsl_chan->dev, dest + test_size / 2,
 804                                         test_size / 4, DMA_FROM_DEVICE);
 805         tx2 = fsl_dma_prep_memcpy(chan, dma_dest, dma_src, test_size / 4, 0);
 806         async_tx_ack(tx2);
 807
 808         /* TX 3 */
 809         dma_src = dma_map_single(fsl_chan->dev, src + test_size * 3 / 4,
 810                                         test_size / 4, DMA_TO_DEVICE);
 811         dma_dest = dma_map_single(fsl_chan->dev, dest + test_size * 3 / 4,
 812                                         test_size / 4, DMA_FROM_DEVICE);
 813         tx3 = fsl_dma_prep_memcpy(chan, dma_dest, dma_src, test_size / 4, 0);
 814         async_tx_ack(tx3);
 815
 816         /* Test exchanging the prepared tx sort */
 817         cookie = fsl_dma_tx_submit(tx3);
 818         cookie = fsl_dma_tx_submit(tx2);
 819
 820 #ifdef FSL_DMA_CALLBACKTEST
 821         if (dma_has_cap(DMA_INTERRUPT, ((struct fsl_dma_device *)
 822             dev_get_drvdata(fsl_chan->dev->parent))->common.cap_mask)) {
 823                 tx3->callback = fsl_dma_callback_test;
 824                 tx3->callback_param = fsl_chan;
 825         }
 826 #endif
 827         fsl_dma_memcpy_issue_pending(chan);
 828         msleep(2);
 829
 830         if (fsl_dma_is_complete(chan, cookie, NULL, NULL) != DMA_SUCCESS) {
 831                 dev_err(fsl_chan->dev, "selftest: Time out!\n");
 832                 err = -ENODEV;
 833                 goto free_resources;
 834         }
 835
 836         err = memcmp(src, dest, test_size);
 837         if (err) {
 838                 for (i = 0; (*(src + i) == *(dest + i)) && (i < test_size);
 839                                 i++);
 840                 dev_err(fsl_chan->dev, "selftest: Test failed, data %d/%d is "
 841                                 "error! src 0x%x, dest 0x%x\n",
 842                                 i, test_size, *(src + i), *(dest + i));
 843         }
 844
 845 free_resources:
 846         fsl_dma_free_chan_resources(chan);
 847 out:
 848         kfree(src);
 849         return err;
 850 }
 851
 852 static int __devinit of_fsl_dma_chan_probe(struct of_device *dev,
 853                         const struct of_device_id *match)
 854 {
 855         struct fsl_dma_device *fdev;
 856         struct fsl_dma_chan *new_fsl_chan;
 857         int err;
 858
 859         fdev = dev_get_drvdata(dev->dev.parent);
 860         BUG_ON(!fdev);
 861
 862         /* alloc channel */
 863         new_fsl_chan = kzalloc(sizeof(struct fsl_dma_chan), GFP_KERNEL);
 864         if (!new_fsl_chan) {
 865                 dev_err(&dev->dev, "No free memory for allocating "
 866                                 "dma channels!\n");
 867                 err = -ENOMEM;
 868                 goto err;
 869         }
 870
 871         /* get dma channel register base */
 872         err = of_address_to_resource(dev->node, 0, &new_fsl_chan->reg);
 873         if (err) {
 874                 dev_err(&dev->dev, "Can't get %s property 'reg'\n",
 875                                 dev->node->full_name);
 876                 goto err;
 877         }
 878
 879         new_fsl_chan->feature = *(u32 *)match->data;
 880
 881         if (!fdev->feature)
 882                 fdev->feature = new_fsl_chan->feature;
 883
 884         /* If the DMA device's feature is different than its channels',
 885          * report the bug.
 886          */
 887         WARN_ON(fdev->feature != new_fsl_chan->feature);
 888
 889         new_fsl_chan->dev = &dev->dev;
 890         new_fsl_chan->reg_base = ioremap(new_fsl_chan->reg.start,
 891                         new_fsl_chan->reg.end - new_fsl_chan->reg.start + 1);
 892
 893         new_fsl_chan->id = ((new_fsl_chan->reg.start - 0x100) & 0xfff) >> 7;
 894         if (new_fsl_chan->id > FSL_DMA_MAX_CHANS_PER_DEVICE) {
 895                 dev_err(&dev->dev, "There is no %d channel!\n",
 896                                 new_fsl_chan->id);
 897                 err = -EINVAL;
 898                 goto err;
 899         }
 900         fdev->chan[new_fsl_chan->id] = new_fsl_chan;
 901         tasklet_init(&new_fsl_chan->tasklet, dma_do_tasklet,
 902                         (unsigned long)new_fsl_chan);
 903
 904         /* Init the channel */
 905         dma_init(new_fsl_chan);
 906
 907         /* Clear cdar registers */
 908         set_cdar(new_fsl_chan, 0);
 909
 910         switch (new_fsl_chan->feature & FSL_DMA_IP_MASK) {
 911         case FSL_DMA_IP_85XX:
 912                 new_fsl_chan->toggle_ext_start = fsl_chan_toggle_ext_start;
 913                 new_fsl_chan->toggle_ext_pause = fsl_chan_toggle_ext_pause;
 914         case FSL_DMA_IP_83XX:
 915                 new_fsl_chan->set_src_loop_size = fsl_chan_set_src_loop_size;
 916                 new_fsl_chan->set_dest_loop_size = fsl_chan_set_dest_loop_size;
 917         }
 918
 919         spin_lock_init(&new_fsl_chan->desc_lock);
 920         INIT_LIST_HEAD(&new_fsl_chan->ld_queue);
 921
 922         new_fsl_chan->common.device = &fdev->common;
 923
 924         /* Add the channel to DMA device channel list */
 925         list_add_tail(&new_fsl_chan->common.device_node,
 926                         &fdev->common.channels);
 927         fdev->common.chancnt++;
 928
 929         new_fsl_chan->irq = irq_of_parse_and_map(dev->node, 0);
 930         if (new_fsl_chan->irq != NO_IRQ) {
 931                 err = request_irq(new_fsl_chan->irq,
 932                                         &fsl_dma_chan_do_interrupt, IRQF_SHARED,
 933                                         "fsldma-channel", new_fsl_chan);
 934                 if (err) {
 935                         dev_err(&dev->dev, "DMA channel %s request_irq error "
 936                                 "with return %d\n", dev->node->full_name, err);
 937                         goto err;
 938                 }
 939         }
 940
 941 #ifdef CONFIG_FSL_DMA_SELFTEST
 942         err = fsl_dma_self_test(new_fsl_chan);
 943         if (err)
 944                 goto err;
 945 #endif
 946
 947         dev_info(&dev->dev, "#%d (%s), irq %d\n", new_fsl_chan->id,
 948                                 match->compatible, new_fsl_chan->irq);
 949
 950         return 0;
 951 err:
 952         dma_halt(new_fsl_chan);
 953         iounmap(new_fsl_chan->reg_base);
 954         free_irq(new_fsl_chan->irq, new_fsl_chan);
 955         list_del(&new_fsl_chan->common.device_node);
 956         kfree(new_fsl_chan);
 957         return err;
 958 }
 959
 960 const u32 mpc8540_dma_ip_feature = FSL_DMA_IP_85XX | FSL_DMA_BIG_ENDIAN;
 961 const u32 mpc8349_dma_ip_feature = FSL_DMA_IP_83XX | FSL_DMA_LITTLE_ENDIAN;
 962
 963 static struct of_device_id of_fsl_dma_chan_ids[] = {
 964         {
 965                 .compatible = "fsl,mpc8540-dma-channel",
 966                 .data = (void *)&mpc8540_dma_ip_feature,
 967         },
 968         {
 969                 .compatible = "fsl,mpc8349-dma-channel",
 970                 .data = (void *)&mpc8349_dma_ip_feature,
 971         },
 972         {}
 973 };
 974
 975 static struct of_platform_driver of_fsl_dma_chan_driver = {
 976         .name = "of-fsl-dma-channel",
 977         .match_table = of_fsl_dma_chan_ids,
 978         .probe = of_fsl_dma_chan_probe,
 979 };
 980
 981 static __init int of_fsl_dma_chan_init(void)
 982 {
 983         return of_register_platform_driver(&of_fsl_dma_chan_driver);
 984 }
 985
 986 static int __devinit of_fsl_dma_probe(struct of_device *dev,
 987                         const struct of_device_id *match)
 988 {
 989         int err;
 990         unsigned int irq;
 991         struct fsl_dma_device *fdev;
 992
 993         fdev = kzalloc(sizeof(struct fsl_dma_device), GFP_KERNEL);
 994         if (!fdev) {
 995                 dev_err(&dev->dev, "No enough memory for 'priv'\n");
 996                 err = -ENOMEM;
 997                 goto err;
 998         }
 999         fdev->dev = &dev->dev;
1000         INIT_LIST_HEAD(&fdev->common.channels);
1001
1002         /* get DMA controller register base */
1003         err = of_address_to_resource(dev->node, 0, &fdev->reg);
1004         if (err) {
1005                 dev_err(&dev->dev, "Can't get %s property 'reg'\n",
1006                                 dev->node->full_name);
1007                 goto err;
1008         }
1009
1010         dev_info(&dev->dev, "Probe the Freescale DMA driver for %s "
1011                         "controller at 0x%08x...\n",
1012                         match->compatible, fdev->reg.start);
1013         fdev->reg_base = ioremap(fdev->reg.start, fdev->reg.end
1014                                                 - fdev->reg.start + 1);
1015
1016         dma_cap_set(DMA_MEMCPY, fdev->common.cap_mask);
1017         dma_cap_set(DMA_INTERRUPT, fdev->common.cap_mask);
1018         fdev->common.device_alloc_chan_resources = fsl_dma_alloc_chan_resources;
1019         fdev->common.device_free_chan_resources = fsl_dma_free_chan_resources;
1020         fdev->common.device_prep_dma_memcpy = fsl_dma_prep_memcpy;
1021         fdev->common.device_is_tx_complete = fsl_dma_is_complete;
1022         fdev->common.device_issue_pending = fsl_dma_memcpy_issue_pending;
1023         fdev->common.device_dependency_added = fsl_dma_dependency_added;
1024         fdev->common.dev = &dev->dev;
1025
1026         irq = irq_of_parse_and_map(dev->node, 0);
1027         if (irq != NO_IRQ) {
1028                 err = request_irq(irq, &fsl_dma_do_interrupt, IRQF_SHARED,
1029                                         "fsldma-device", fdev);
1030                 if (err) {
1031                         dev_err(&dev->dev, "DMA device request_irq error "
1032                                 "with return %d\n", err);
1033                         goto err;
1034                 }
1035         }
1036
1037         dev_set_drvdata(&(dev->dev), fdev);
1038         of_platform_bus_probe(dev->node, of_fsl_dma_chan_ids, &dev->dev);
1039
1040         dma_async_device_register(&fdev->common);
1041         return 0;
1042
1043 err:
1044         iounmap(fdev->reg_base);
1045         kfree(fdev);
1046         return err;
1047 }
1048
1049 static struct of_device_id of_fsl_dma_ids[] = {
1050         { .compatible = "fsl,mpc8540-dma", },
1051         { .compatible = "fsl,mpc8349-dma", },
1052         {}
1053 };
1054
1055 static struct of_platform_driver of_fsl_dma_driver = {
1056         .name = "of-fsl-dma",
1057         .match_table = of_fsl_dma_ids,
1058         .probe = of_fsl_dma_probe,
1059 };
1060
1061 static __init int of_fsl_dma_init(void)
1062 {
1063         return of_register_platform_driver(&of_fsl_dma_driver);
1064 }
1065
1066 subsys_initcall(of_fsl_dma_chan_init);
1067 subsys_initcall(of_fsl_dma_init);