drivers/dma/coh901318.c

   1 /*
   2  * driver/dma/coh901318.c
   3  *
   4  * Copyright (C) 2007-2009 ST-Ericsson
   5  * License terms: GNU General Public License (GPL) version 2
   6  * DMA driver for COH 901 318
   7  * Author: Per Friden <per.friden@stericsson.com>
   8  */
   9
  10 #include <linux/init.h>
  11 #include <linux/module.h>
  12 #include <linux/kernel.h> /* printk() */
  13 #include <linux/fs.h> /* everything... */
  14 #include <linux/scatterlist.h>
  15 #include <linux/slab.h> /* kmalloc() */
  16 #include <linux/dmaengine.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/device.h>
  19 #include <linux/irqreturn.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/io.h>
  22 #include <linux/uaccess.h>
  23 #include <linux/debugfs.h>
  24 #include <mach/coh901318.h>
  25
  26 #include "coh901318_lli.h"
  27
  28 #define COHC_2_DEV(cohc) (&cohc->chan.dev->device)
  29
  30 #ifdef VERBOSE_DEBUG
  31 #define COH_DBG(x) ({ if (1) x; 0; })
  32 #else
  33 #define COH_DBG(x) ({ if (0) x; 0; })
  34 #endif
  35
  36 struct coh901318_desc {
  37         struct dma_async_tx_descriptor desc;
  38         struct list_head node;
  39         struct scatterlist *sg;
  40         unsigned int sg_len;
  41         struct coh901318_lli *lli;
  42         enum dma_data_direction dir;
  43         unsigned long flags;
  44         u32 head_config;
  45         u32 head_ctrl;
  46 };
  47
  48 struct coh901318_base {
  49         struct device *dev;
  50         void __iomem *virtbase;
  51         struct coh901318_pool pool;
  52         struct powersave pm;
  53         struct dma_device dma_slave;
  54         struct dma_device dma_memcpy;
  55         struct coh901318_chan *chans;
  56         struct coh901318_platform *platform;
  57 };
  58
  59 struct coh901318_chan {
  60         spinlock_t lock;
  61         int allocated;
  62         int completed;
  63         int id;
  64         int stopped;
  65
  66         struct work_struct free_work;
  67         struct dma_chan chan;
  68
  69         struct tasklet_struct tasklet;
  70
  71         struct list_head active;
  72         struct list_head queue;
  73         struct list_head free;
  74
  75         unsigned long nbr_active_done;
  76         unsigned long busy;
  77
  78         u32 runtime_addr;
  79         u32 runtime_ctrl;
  80
  81         struct coh901318_base *base;
  82 };
  83
  84 static void coh901318_list_print(struct coh901318_chan *cohc,
  85                                  struct coh901318_lli *lli)
  86 {
  87         struct coh901318_lli *l = lli;
  88         int i = 0;
  89
  90         while (l) {
  91                 dev_vdbg(COHC_2_DEV(cohc), "i %d, lli %p, ctrl 0x%x, src 0x%x"
  92                          ", dst 0x%x, link 0x%x virt_link_addr 0x%p\n",
  93                          i, l, l->control, l->src_addr, l->dst_addr,
  94                          l->link_addr, l->virt_link_addr);
  95                 i++;
  96                 l = l->virt_link_addr;
  97         }
  98 }
  99
 100 #ifdef CONFIG_DEBUG_FS
 101
 102 #define COH901318_DEBUGFS_ASSIGN(x, y) (x = y)
 103
 104 static struct coh901318_base *debugfs_dma_base;
 105 static struct dentry *dma_dentry;
 106
 107 static int coh901318_debugfs_open(struct inode *inode, struct file *file)
 108 {
 109
 110         file->private_data = inode->i_private;
 111         return 0;
 112 }
 113
 114 static int coh901318_debugfs_read(struct file *file, char __user *buf,
 115                                   size_t count, loff_t *f_pos)
 116 {
 117         u64 started_channels = debugfs_dma_base->pm.started_channels;
 118         int pool_count = debugfs_dma_base->pool.debugfs_pool_counter;
 119         int i;
 120         int ret = 0;
 121         char *dev_buf;
 122         char *tmp;
 123         int dev_size;
 124
 125         dev_buf = kmalloc(4*1024, GFP_KERNEL);
 126         if (dev_buf == NULL)
 127                 goto err_kmalloc;
 128         tmp = dev_buf;
 129
 130         tmp += sprintf(tmp, "DMA -- enabled dma channels\n");
 131
 132         for (i = 0; i < debugfs_dma_base->platform->max_channels; i++)
 133                 if (started_channels & (1 << i))
 134                         tmp += sprintf(tmp, "channel %d\n", i);
 135
 136         tmp += sprintf(tmp, "Pool alloc nbr %d\n", pool_count);
 137         dev_size = tmp  - dev_buf;
 138
 139         /* No more to read if offset != 0 */
 140         if (*f_pos > dev_size)
 141                 goto out;
 142
 143         if (count > dev_size - *f_pos)
 144                 count = dev_size - *f_pos;
 145
 146         if (copy_to_user(buf, dev_buf + *f_pos, count))
 147                 ret = -EINVAL;
 148         ret = count;
 149         *f_pos += count;
 150
 151  out:
 152         kfree(dev_buf);
 153         return ret;
 154
 155  err_kmalloc:
 156         return 0;
 157 }
 158
 159 static const struct file_operations coh901318_debugfs_status_operations = {
 160         .owner          = THIS_MODULE,
 161         .open           = coh901318_debugfs_open,
 162         .read           = coh901318_debugfs_read,
 163         .llseek         = default_llseek,
 164 };
 165
 166
 167 static int __init init_coh901318_debugfs(void)
 168 {
 169
 170         dma_dentry = debugfs_create_dir("dma", NULL);
 171
 172         (void) debugfs_create_file("status",
 173                                    S_IFREG | S_IRUGO,
 174                                    dma_dentry, NULL,
 175                                    &coh901318_debugfs_status_operations);
 176         return 0;
 177 }
 178
 179 static void __exit exit_coh901318_debugfs(void)
 180 {
 181         debugfs_remove_recursive(dma_dentry);
 182 }
 183
 184 module_init(init_coh901318_debugfs);
 185 module_exit(exit_coh901318_debugfs);
 186 #else
 187
 188 #define COH901318_DEBUGFS_ASSIGN(x, y)
 189
 190 #endif /* CONFIG_DEBUG_FS */
 191
 192 static inline struct coh901318_chan *to_coh901318_chan(struct dma_chan *chan)
 193 {
 194         return container_of(chan, struct coh901318_chan, chan);
 195 }
 196
 197 static inline dma_addr_t
 198 cohc_dev_addr(struct coh901318_chan *cohc)
 199 {
 200         /* Runtime supplied address will take precedence */
 201         if (cohc->runtime_addr)
 202                 return cohc->runtime_addr;
 203         return cohc->base->platform->chan_conf[cohc->id].dev_addr;
 204 }
 205
 206 static inline const struct coh901318_params *
 207 cohc_chan_param(struct coh901318_chan *cohc)
 208 {
 209         return &cohc->base->platform->chan_conf[cohc->id].param;
 210 }
 211
 212 static inline const struct coh_dma_channel *
 213 cohc_chan_conf(struct coh901318_chan *cohc)
 214 {
 215         return &cohc->base->platform->chan_conf[cohc->id];
 216 }
 217
 218 static void enable_powersave(struct coh901318_chan *cohc)
 219 {
 220         unsigned long flags;
 221         struct powersave *pm = &cohc->base->pm;
 222
 223         spin_lock_irqsave(&pm->lock, flags);
 224
 225         pm->started_channels &= ~(1ULL << cohc->id);
 226
 227         if (!pm->started_channels) {
 228                 /* DMA no longer intends to access memory */
 229                 cohc->base->platform->access_memory_state(cohc->base->dev,
 230                                                           false);
 231         }
 232
 233         spin_unlock_irqrestore(&pm->lock, flags);
 234 }
 235 static void disable_powersave(struct coh901318_chan *cohc)
 236 {
 237         unsigned long flags;
 238         struct powersave *pm = &cohc->base->pm;
 239
 240         spin_lock_irqsave(&pm->lock, flags);
 241
 242         if (!pm->started_channels) {
 243                 /* DMA intends to access memory */
 244                 cohc->base->platform->access_memory_state(cohc->base->dev,
 245                                                           true);
 246         }
 247
 248         pm->started_channels |= (1ULL << cohc->id);
 249
 250         spin_unlock_irqrestore(&pm->lock, flags);
 251 }
 252
 253 static inline int coh901318_set_ctrl(struct coh901318_chan *cohc, u32 control)
 254 {
 255         int channel = cohc->id;
 256         void __iomem *virtbase = cohc->base->virtbase;
 257
 258         writel(control,
 259                virtbase + COH901318_CX_CTRL +
 260                COH901318_CX_CTRL_SPACING * channel);
 261         return 0;
 262 }
 263
 264 static inline int coh901318_set_conf(struct coh901318_chan *cohc, u32 conf)
 265 {
 266         int channel = cohc->id;
 267         void __iomem *virtbase = cohc->base->virtbase;
 268
 269         writel(conf,
 270                virtbase + COH901318_CX_CFG +
 271                COH901318_CX_CFG_SPACING*channel);
 272         return 0;
 273 }
 274
 275
 276 static int coh901318_start(struct coh901318_chan *cohc)
 277 {
 278         u32 val;
 279         int channel = cohc->id;
 280         void __iomem *virtbase = cohc->base->virtbase;
 281
 282         disable_powersave(cohc);
 283
 284         val = readl(virtbase + COH901318_CX_CFG +
 285                     COH901318_CX_CFG_SPACING * channel);
 286
 287         /* Enable channel */
 288         val |= COH901318_CX_CFG_CH_ENABLE;
 289         writel(val, virtbase + COH901318_CX_CFG +
 290                COH901318_CX_CFG_SPACING * channel);
 291
 292         return 0;
 293 }
 294
 295 static int coh901318_prep_linked_list(struct coh901318_chan *cohc,
 296                                       struct coh901318_lli *lli)
 297 {
 298         int channel = cohc->id;
 299         void __iomem *virtbase = cohc->base->virtbase;
 300
 301         BUG_ON(readl(virtbase + COH901318_CX_STAT +
 302                      COH901318_CX_STAT_SPACING*channel) &
 303                COH901318_CX_STAT_ACTIVE);
 304
 305         writel(lli->src_addr,
 306                virtbase + COH901318_CX_SRC_ADDR +
 307                COH901318_CX_SRC_ADDR_SPACING * channel);
 308
 309         writel(lli->dst_addr, virtbase +
 310                COH901318_CX_DST_ADDR +
 311                COH901318_CX_DST_ADDR_SPACING * channel);
 312
 313         writel(lli->link_addr, virtbase + COH901318_CX_LNK_ADDR +
 314                COH901318_CX_LNK_ADDR_SPACING * channel);
 315
 316         writel(lli->control, virtbase + COH901318_CX_CTRL +
 317                COH901318_CX_CTRL_SPACING * channel);
 318
 319         return 0;
 320 }
 321 static dma_cookie_t
 322 coh901318_assign_cookie(struct coh901318_chan *cohc,
 323                         struct coh901318_desc *cohd)
 324 {
 325         dma_cookie_t cookie = cohc->chan.cookie;
 326
 327         if (++cookie < 0)
 328                 cookie = 1;
 329
 330         cohc->chan.cookie = cookie;
 331         cohd->desc.cookie = cookie;
 332
 333         return cookie;
 334 }
 335
 336 static struct coh901318_desc *
 337 coh901318_desc_get(struct coh901318_chan *cohc)
 338 {
 339         struct coh901318_desc *desc;
 340
 341         if (list_empty(&cohc->free)) {
 342                 /* alloc new desc because we're out of used ones
 343                  * TODO: alloc a pile of descs instead of just one,
 344                  * avoid many small allocations.
 345                  */
 346                 desc = kzalloc(sizeof(struct coh901318_desc), GFP_NOWAIT);
 347                 if (desc == NULL)
 348                         goto out;
 349                 INIT_LIST_HEAD(&desc->node);
 350                 dma_async_tx_descriptor_init(&desc->desc, &cohc->chan);
 351         } else {
 352                 /* Reuse an old desc. */
 353                 desc = list_first_entry(&cohc->free,
 354                                         struct coh901318_desc,
 355                                         node);
 356                 list_del(&desc->node);
 357                 /* Initialize it a bit so it's not insane */
 358                 desc->sg = NULL;
 359                 desc->sg_len = 0;
 360                 desc->desc.callback = NULL;
 361                 desc->desc.callback_param = NULL;
 362         }
 363
 364  out:
 365         return desc;
 366 }
 367
 368 static void
 369 coh901318_desc_free(struct coh901318_chan *cohc, struct coh901318_desc *cohd)
 370 {
 371         list_add_tail(&cohd->node, &cohc->free);
 372 }
 373
 374 /* call with irq lock held */
 375 static void
 376 coh901318_desc_submit(struct coh901318_chan *cohc, struct coh901318_desc *desc)
 377 {
 378         list_add_tail(&desc->node, &cohc->active);
 379 }
 380
 381 static struct coh901318_desc *
 382 coh901318_first_active_get(struct coh901318_chan *cohc)
 383 {
 384         struct coh901318_desc *d;
 385
 386         if (list_empty(&cohc->active))
 387                 return NULL;
 388
 389         d = list_first_entry(&cohc->active,
 390                              struct coh901318_desc,
 391                              node);
 392         return d;
 393 }
 394
 395 static void
 396 coh901318_desc_remove(struct coh901318_desc *cohd)
 397 {
 398         list_del(&cohd->node);
 399 }
 400
 401 static void
 402 coh901318_desc_queue(struct coh901318_chan *cohc, struct coh901318_desc *desc)
 403 {
 404         list_add_tail(&desc->node, &cohc->queue);
 405 }
 406
 407 static struct coh901318_desc *
 408 coh901318_first_queued(struct coh901318_chan *cohc)
 409 {
 410         struct coh901318_desc *d;
 411
 412         if (list_empty(&cohc->queue))
 413                 return NULL;
 414
 415         d = list_first_entry(&cohc->queue,
 416                              struct coh901318_desc,
 417                              node);
 418         return d;
 419 }
 420
 421 static inline u32 coh901318_get_bytes_in_lli(struct coh901318_lli *in_lli)
 422 {
 423         struct coh901318_lli *lli = in_lli;
 424         u32 bytes = 0;
 425
 426         while (lli) {
 427                 bytes += lli->control & COH901318_CX_CTRL_TC_VALUE_MASK;
 428                 lli = lli->virt_link_addr;
 429         }
 430         return bytes;
 431 }
 432
 433 /*
 434  * Get the number of bytes left to transfer on this channel,
 435  * it is unwise to call this before stopping the channel for
 436  * absolute measures, but for a rough guess you can still call
 437  * it.
 438  */
 439 static u32 coh901318_get_bytes_left(struct dma_chan *chan)
 440 {
 441         struct coh901318_chan *cohc = to_coh901318_chan(chan);
 442         struct coh901318_desc *cohd;
 443         struct list_head *pos;
 444         unsigned long flags;
 445         u32 left = 0;
 446         int i = 0;
 447
 448         spin_lock_irqsave(&cohc->lock, flags);
 449
 450         /*
 451          * If there are many queued jobs, we iterate and add the
 452          * size of them all. We take a special look on the first
 453          * job though, since it is probably active.
 454          */
 455         list_for_each(pos, &cohc->active) {
 456                 /*
 457                  * The first job in the list will be working on the
 458                  * hardware. The job can be stopped but still active,
 459                  * so that the transfer counter is somewhere inside
 460                  * the buffer.
 461                  */
 462                 cohd = list_entry(pos, struct coh901318_desc, node);
 463
 464                 if (i == 0) {
 465                         struct coh901318_lli *lli;
 466                         dma_addr_t ladd;
 467
 468                         /* Read current transfer count value */
 469                         left = readl(cohc->base->virtbase +
 470                                      COH901318_CX_CTRL +
 471                                      COH901318_CX_CTRL_SPACING * cohc->id) &
 472                                 COH901318_CX_CTRL_TC_VALUE_MASK;
 473
 474                         /* See if the transfer is linked... */
 475                         ladd = readl(cohc->base->virtbase +
 476                                      COH901318_CX_LNK_ADDR +
 477                                      COH901318_CX_LNK_ADDR_SPACING *
 478                                      cohc->id) &
 479                                 ~COH901318_CX_LNK_LINK_IMMEDIATE;
 480                         /* Single transaction */
 481                         if (!ladd)
 482                                 continue;
 483
 484                         /*
 485                          * Linked transaction, follow the lli, find the
 486                          * currently processing lli, and proceed to the next
 487                          */
 488                         lli = cohd->lli;
 489                         while (lli && lli->link_addr != ladd)
 490                                 lli = lli->virt_link_addr;
 491
 492                         if (lli)
 493                                 lli = lli->virt_link_addr;
 494
 495                         /*
 496                          * Follow remaining lli links around to count the total
 497                          * number of bytes left
 498                          */
 499                         left += coh901318_get_bytes_in_lli(lli);
 500                 } else {
 501                         left += coh901318_get_bytes_in_lli(cohd->lli);
 502                 }
 503                 i++;
 504         }
 505
 506         /* Also count bytes in the queued jobs */
 507         list_for_each(pos, &cohc->queue) {
 508                 cohd = list_entry(pos, struct coh901318_desc, node);
 509                 left += coh901318_get_bytes_in_lli(cohd->lli);
 510         }
 511
 512         spin_unlock_irqrestore(&cohc->lock, flags);
 513
 514         return left;
 515 }
 516
 517 /*
 518  * Pauses a transfer without losing data. Enables power save.
 519  * Use this function in conjunction with coh901318_resume.
 520  */
 521 static void coh901318_pause(struct dma_chan *chan)
 522 {
 523         u32 val;
 524         unsigned long flags;
 525         struct coh901318_chan *cohc = to_coh901318_chan(chan);
 526         int channel = cohc->id;
 527         void __iomem *virtbase = cohc->base->virtbase;
 528
 529         spin_lock_irqsave(&cohc->lock, flags);
 530
 531         /* Disable channel in HW */
 532         val = readl(virtbase + COH901318_CX_CFG +
 533                     COH901318_CX_CFG_SPACING * channel);
 534
 535         /* Stopping infinite transfer */
 536         if ((val & COH901318_CX_CTRL_TC_ENABLE) == 0 &&
 537             (val & COH901318_CX_CFG_CH_ENABLE))
 538                 cohc->stopped = 1;
 539
 540
 541         val &= ~COH901318_CX_CFG_CH_ENABLE;
 542         /* Enable twice, HW bug work around */
 543         writel(val, virtbase + COH901318_CX_CFG +
 544                COH901318_CX_CFG_SPACING * channel);
 545         writel(val, virtbase + COH901318_CX_CFG +
 546                COH901318_CX_CFG_SPACING * channel);
 547
 548         /* Spin-wait for it to actually go inactive */
 549         while (readl(virtbase + COH901318_CX_STAT+COH901318_CX_STAT_SPACING *
 550                      channel) & COH901318_CX_STAT_ACTIVE)
 551                 cpu_relax();
 552
 553         /* Check if we stopped an active job */
 554         if ((readl(virtbase + COH901318_CX_CTRL+COH901318_CX_CTRL_SPACING *
 555                    channel) & COH901318_CX_CTRL_TC_VALUE_MASK) > 0)
 556                 cohc->stopped = 1;
 557
 558         enable_powersave(cohc);
 559
 560         spin_unlock_irqrestore(&cohc->lock, flags);
 561 }
 562
 563 /* Resumes a transfer that has been stopped via 300_dma_stop(..).
 564    Power save is handled.
 565 */
 566 static void coh901318_resume(struct dma_chan *chan)
 567 {
 568         u32 val;
 569         unsigned long flags;
 570         struct coh901318_chan *cohc = to_coh901318_chan(chan);
 571         int channel = cohc->id;
 572
 573         spin_lock_irqsave(&cohc->lock, flags);
 574
 575         disable_powersave(cohc);
 576
 577         if (cohc->stopped) {
 578                 /* Enable channel in HW */
 579                 val = readl(cohc->base->virtbase + COH901318_CX_CFG +
 580                             COH901318_CX_CFG_SPACING * channel);
 581
 582                 val |= COH901318_CX_CFG_CH_ENABLE;
 583
 584                 writel(val, cohc->base->virtbase + COH901318_CX_CFG +
 585                        COH901318_CX_CFG_SPACING*channel);
 586
 587                 cohc->stopped = 0;
 588         }
 589
 590         spin_unlock_irqrestore(&cohc->lock, flags);
 591 }
 592
 593 bool coh901318_filter_id(struct dma_chan *chan, void *chan_id)
 594 {
 595         unsigned int ch_nr = (unsigned int) chan_id;
 596
 597         if (ch_nr == to_coh901318_chan(chan)->id)
 598                 return true;
 599
 600         return false;
 601 }
 602 EXPORT_SYMBOL(coh901318_filter_id);
 603
 604 /*
 605  * DMA channel allocation
 606  */
 607 static int coh901318_config(struct coh901318_chan *cohc,
 608                             struct coh901318_params *param)
 609 {
 610         unsigned long flags;
 611         const struct coh901318_params *p;
 612         int channel = cohc->id;
 613         void __iomem *virtbase = cohc->base->virtbase;
 614
 615         spin_lock_irqsave(&cohc->lock, flags);
 616
 617         if (param)
 618                 p = param;
 619         else
 620                 p = &cohc->base->platform->chan_conf[channel].param;
 621
 622         /* Clear any pending BE or TC interrupt */
 623         if (channel < 32) {
 624                 writel(1 << channel, virtbase + COH901318_BE_INT_CLEAR1);
 625                 writel(1 << channel, virtbase + COH901318_TC_INT_CLEAR1);
 626         } else {
 627                 writel(1 << (channel - 32), virtbase +
 628                        COH901318_BE_INT_CLEAR2);
 629                 writel(1 << (channel - 32), virtbase +
 630                        COH901318_TC_INT_CLEAR2);
 631         }
 632
 633         coh901318_set_conf(cohc, p->config);
 634         coh901318_set_ctrl(cohc, p->ctrl_lli_last);
 635
 636         spin_unlock_irqrestore(&cohc->lock, flags);
 637
 638         return 0;
 639 }
 640
 641 /* must lock when calling this function
 642  * start queued jobs, if any
 643  * TODO: start all queued jobs in one go
 644  *
 645  * Returns descriptor if queued job is started otherwise NULL.
 646  * If the queue is empty NULL is returned.
 647  */
 648 static struct coh901318_desc *coh901318_queue_start(struct coh901318_chan *cohc)
 649 {
 650         struct coh901318_desc *cohd;
 651
 652         /*
 653          * start queued jobs, if any
 654          * TODO: transmit all queued jobs in one go
 655          */
 656         cohd = coh901318_first_queued(cohc);
 657
 658         if (cohd != NULL) {
 659                 /* Remove from queue */
 660                 coh901318_desc_remove(cohd);
 661                 /* initiate DMA job */
 662                 cohc->busy = 1;
 663
 664                 coh901318_desc_submit(cohc, cohd);
 665
 666                 /* Program the transaction head */
 667                 coh901318_set_conf(cohc, cohd->head_config);
 668                 coh901318_set_ctrl(cohc, cohd->head_ctrl);
 669                 coh901318_prep_linked_list(cohc, cohd->lli);
 670
 671                 /* start dma job on this channel */
 672                 coh901318_start(cohc);
 673
 674         }
 675
 676         return cohd;
 677 }
 678
 679 /*
 680  * This tasklet is called from the interrupt handler to
 681  * handle each descriptor (DMA job) that is sent to a channel.
 682  */
 683 static void dma_tasklet(unsigned long data)
 684 {
 685         struct coh901318_chan *cohc = (struct coh901318_chan *) data;
 686         struct coh901318_desc *cohd_fin;
 687         unsigned long flags;
 688         dma_async_tx_callback callback;
 689         void *callback_param;
 690
 691         dev_vdbg(COHC_2_DEV(cohc), "[%s] chan_id %d"
 692                  " nbr_active_done %ld\n", __func__,
 693                  cohc->id, cohc->nbr_active_done);
 694
 695         spin_lock_irqsave(&cohc->lock, flags);
 696
 697         /* get first active descriptor entry from list */
 698         cohd_fin = coh901318_first_active_get(cohc);
 699
 700         if (cohd_fin == NULL)
 701                 goto err;
 702
 703         /* locate callback to client */
 704         callback = cohd_fin->desc.callback;
 705         callback_param = cohd_fin->desc.callback_param;
 706
 707         /* sign this job as completed on the channel */
 708         cohc->completed = cohd_fin->desc.cookie;
 709
 710         /* release the lli allocation and remove the descriptor */
 711         coh901318_lli_free(&cohc->base->pool, &cohd_fin->lli);
 712
 713         /* return desc to free-list */
 714         coh901318_desc_remove(cohd_fin);
 715         coh901318_desc_free(cohc, cohd_fin);
 716
 717         spin_unlock_irqrestore(&cohc->lock, flags);
 718
 719         /* Call the callback when we're done */
 720         if (callback)
 721                 callback(callback_param);
 722
 723         spin_lock_irqsave(&cohc->lock, flags);
 724
 725         /*
 726          * If another interrupt fired while the tasklet was scheduling,
 727          * we don't get called twice, so we have this number of active
 728          * counter that keep track of the number of IRQs expected to
 729          * be handled for this channel. If there happen to be more than
 730          * one IRQ to be ack:ed, we simply schedule this tasklet again.
 731          */
 732         cohc->nbr_active_done--;
 733         if (cohc->nbr_active_done) {
 734                 dev_dbg(COHC_2_DEV(cohc), "scheduling tasklet again, new IRQs "
 735                         "came in while we were scheduling this tasklet\n");
 736                 if (cohc_chan_conf(cohc)->priority_high)
 737                         tasklet_hi_schedule(&cohc->tasklet);
 738                 else
 739                         tasklet_schedule(&cohc->tasklet);
 740         }
 741
 742         spin_unlock_irqrestore(&cohc->lock, flags);
 743
 744         return;
 745
 746  err:
 747         spin_unlock_irqrestore(&cohc->lock, flags);
 748         dev_err(COHC_2_DEV(cohc), "[%s] No active dma desc\n", __func__);
 749 }
 750
 751
 752 /* called from interrupt context */
 753 static void dma_tc_handle(struct coh901318_chan *cohc)
 754 {
 755         /*
 756          * If the channel is not allocated, then we shouldn't have
 757          * any TC interrupts on it.
 758          */
 759         if (!cohc->allocated) {
 760                 dev_err(COHC_2_DEV(cohc), "spurious interrupt from "
 761                         "unallocated channel\n");
 762                 return;
 763         }
 764
 765         spin_lock(&cohc->lock);
 766
 767         /*
 768          * When we reach this point, at least one queue item
 769          * should have been moved over from cohc->queue to
 770          * cohc->active and run to completion, that is why we're
 771          * getting a terminal count interrupt is it not?
 772          * If you get this BUG() the most probable cause is that
 773          * the individual nodes in the lli chain have IRQ enabled,
 774          * so check your platform config for lli chain ctrl.
 775          */
 776         BUG_ON(list_empty(&cohc->active));
 777
 778         cohc->nbr_active_done++;
 779
 780         /*
 781          * This attempt to take a job from cohc->queue, put it
 782          * into cohc->active and start it.
 783          */
 784         if (coh901318_queue_start(cohc) == NULL)
 785                 cohc->busy = 0;
 786
 787         spin_unlock(&cohc->lock);
 788
 789         /*
 790          * This tasklet will remove items from cohc->active
 791          * and thus terminates them.
 792          */
 793         if (cohc_chan_conf(cohc)->priority_high)
 794                 tasklet_hi_schedule(&cohc->tasklet);
 795         else
 796                 tasklet_schedule(&cohc->tasklet);
 797 }
 798
 799
 800 static irqreturn_t dma_irq_handler(int irq, void *dev_id)
 801 {
 802         u32 status1;
 803         u32 status2;
 804         int i;
 805         int ch;
 806         struct coh901318_base *base  = dev_id;
 807         struct coh901318_chan *cohc;
 808         void __iomem *virtbase = base->virtbase;
 809
 810         status1 = readl(virtbase + COH901318_INT_STATUS1);
 811         status2 = readl(virtbase + COH901318_INT_STATUS2);
 812
 813         if (unlikely(status1 == 0 && status2 == 0)) {
 814                 dev_warn(base->dev, "spurious DMA IRQ from no channel!\n");
 815                 return IRQ_HANDLED;
 816         }
 817
 818         /* TODO: consider handle IRQ in tasklet here to
 819          *       minimize interrupt latency */
 820
 821         /* Check the first 32 DMA channels for IRQ */
 822         while (status1) {
 823                 /* Find first bit set, return as a number. */
 824                 i = ffs(status1) - 1;
 825                 ch = i;
 826
 827                 cohc = &base->chans[ch];
 828                 spin_lock(&cohc->lock);
 829
 830                 /* Mask off this bit */
 831                 status1 &= ~(1 << i);
 832                 /* Check the individual channel bits */
 833                 if (test_bit(i, virtbase + COH901318_BE_INT_STATUS1)) {
 834                         dev_crit(COHC_2_DEV(cohc),
 835                                  "DMA bus error on channel %d!\n", ch);
 836                         BUG_ON(1);
 837                         /* Clear BE interrupt */
 838                         __set_bit(i, virtbase + COH901318_BE_INT_CLEAR1);
 839                 } else {
 840                         /* Caused by TC, really? */
 841                         if (unlikely(!test_bit(i, virtbase +
 842                                                COH901318_TC_INT_STATUS1))) {
 843                                 dev_warn(COHC_2_DEV(cohc),
 844                                          "ignoring interrupt not caused by terminal count on channel %d\n", ch);
 845                                 /* Clear TC interrupt */
 846                                 BUG_ON(1);
 847                                 __set_bit(i, virtbase + COH901318_TC_INT_CLEAR1);
 848                         } else {
 849                                 /* Enable powersave if transfer has finished */
 850                                 if (!(readl(virtbase + COH901318_CX_STAT +
 851                                             COH901318_CX_STAT_SPACING*ch) &
 852                                       COH901318_CX_STAT_ENABLED)) {
 853                                         enable_powersave(cohc);
 854                                 }
 855
 856                                 /* Must clear TC interrupt before calling
 857                                  * dma_tc_handle
 858                                  * in case tc_handle initiate a new dma job
 859                                  */
 860                                 __set_bit(i, virtbase + COH901318_TC_INT_CLEAR1);
 861
 862                                 dma_tc_handle(cohc);
 863                         }
 864                 }
 865                 spin_unlock(&cohc->lock);
 866         }
 867
 868         /* Check the remaining 32 DMA channels for IRQ */
 869         while (status2) {
 870                 /* Find first bit set, return as a number. */
 871                 i = ffs(status2) - 1;
 872                 ch = i + 32;
 873                 cohc = &base->chans[ch];
 874                 spin_lock(&cohc->lock);
 875
 876                 /* Mask off this bit */
 877                 status2 &= ~(1 << i);
 878                 /* Check the individual channel bits */
 879                 if (test_bit(i, virtbase + COH901318_BE_INT_STATUS2)) {
 880                         dev_crit(COHC_2_DEV(cohc),
 881                                  "DMA bus error on channel %d!\n", ch);
 882                         /* Clear BE interrupt */
 883                         BUG_ON(1);
 884                         __set_bit(i, virtbase + COH901318_BE_INT_CLEAR2);
 885                 } else {
 886                         /* Caused by TC, really? */
 887                         if (unlikely(!test_bit(i, virtbase +
 888                                                COH901318_TC_INT_STATUS2))) {
 889                                 dev_warn(COHC_2_DEV(cohc),
 890                                          "ignoring interrupt not caused by terminal count on channel %d\n", ch);
 891                                 /* Clear TC interrupt */
 892                                 __set_bit(i, virtbase + COH901318_TC_INT_CLEAR2);
 893                                 BUG_ON(1);
 894                         } else {
 895                                 /* Enable powersave if transfer has finished */
 896                                 if (!(readl(virtbase + COH901318_CX_STAT +
 897                                             COH901318_CX_STAT_SPACING*ch) &
 898                                       COH901318_CX_STAT_ENABLED)) {
 899                                         enable_powersave(cohc);
 900                                 }
 901                                 /* Must clear TC interrupt before calling
 902                                  * dma_tc_handle
 903                                  * in case tc_handle initiate a new dma job
 904                                  */
 905                                 __set_bit(i, virtbase + COH901318_TC_INT_CLEAR2);
 906
 907                                 dma_tc_handle(cohc);
 908                         }
 909                 }
 910                 spin_unlock(&cohc->lock);
 911         }
 912
 913         return IRQ_HANDLED;
 914 }
 915
 916 static int coh901318_alloc_chan_resources(struct dma_chan *chan)
 917 {
 918         struct coh901318_chan   *cohc = to_coh901318_chan(chan);
 919         unsigned long flags;
 920
 921         dev_vdbg(COHC_2_DEV(cohc), "[%s] DMA channel %d\n",
 922                  __func__, cohc->id);
 923
 924         if (chan->client_count > 1)
 925                 return -EBUSY;
 926
 927         spin_lock_irqsave(&cohc->lock, flags);
 928
 929         coh901318_config(cohc, NULL);
 930
 931         cohc->allocated = 1;
 932         cohc->completed = chan->cookie = 1;
 933
 934         spin_unlock_irqrestore(&cohc->lock, flags);
 935
 936         return 1;
 937 }
 938
 939 static void
 940 coh901318_free_chan_resources(struct dma_chan *chan)
 941 {
 942         struct coh901318_chan   *cohc = to_coh901318_chan(chan);
 943         int channel = cohc->id;
 944         unsigned long flags;
 945
 946         spin_lock_irqsave(&cohc->lock, flags);
 947
 948         /* Disable HW */
 949         writel(0x00000000U, cohc->base->virtbase + COH901318_CX_CFG +
 950                COH901318_CX_CFG_SPACING*channel);
 951         writel(0x00000000U, cohc->base->virtbase + COH901318_CX_CTRL +
 952                COH901318_CX_CTRL_SPACING*channel);
 953
 954         cohc->allocated = 0;
 955
 956         spin_unlock_irqrestore(&cohc->lock, flags);
 957
 958         chan->device->device_control(chan, DMA_TERMINATE_ALL, 0);
 959 }
 960
 961
 962 static dma_cookie_t
 963 coh901318_tx_submit(struct dma_async_tx_descriptor *tx)
 964 {
 965         struct coh901318_desc *cohd = container_of(tx, struct coh901318_desc,
 966                                                    desc);
 967         struct coh901318_chan *cohc = to_coh901318_chan(tx->chan);
 968         unsigned long flags;
 969
 970         spin_lock_irqsave(&cohc->lock, flags);
 971
 972         tx->cookie = coh901318_assign_cookie(cohc, cohd);
 973
 974         coh901318_desc_queue(cohc, cohd);
 975
 976         spin_unlock_irqrestore(&cohc->lock, flags);
 977
 978         return tx->cookie;
 979 }
 980
 981 static struct dma_async_tx_descriptor *
 982 coh901318_prep_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
 983                       size_t size, unsigned long flags)
 984 {
 985         struct coh901318_lli *lli;
 986         struct coh901318_desc *cohd;
 987         unsigned long flg;
 988         struct coh901318_chan *cohc = to_coh901318_chan(chan);
 989         int lli_len;
 990         u32 ctrl_last = cohc_chan_param(cohc)->ctrl_lli_last;
 991         int ret;
 992
 993         spin_lock_irqsave(&cohc->lock, flg);
 994
 995         dev_vdbg(COHC_2_DEV(cohc),
 996                  "[%s] channel %d src 0x%x dest 0x%x size %d\n",
 997                  __func__, cohc->id, src, dest, size);
 998
 999         if (flags & DMA_PREP_INTERRUPT)
1000                 /* Trigger interrupt after last lli */
1001                 ctrl_last |= COH901318_CX_CTRL_TC_IRQ_ENABLE;
1002
1003         lli_len = size >> MAX_DMA_PACKET_SIZE_SHIFT;
1004         if ((lli_len << MAX_DMA_PACKET_SIZE_SHIFT) < size)
1005                 lli_len++;
1006
1007         lli = coh901318_lli_alloc(&cohc->base->pool, lli_len);
1008
1009         if (lli == NULL)
1010                 goto err;
1011
1012         ret = coh901318_lli_fill_memcpy(
1013                 &cohc->base->pool, lli, src, size, dest,
1014                 cohc_chan_param(cohc)->ctrl_lli_chained,
1015                 ctrl_last);
1016         if (ret)
1017                 goto err;
1018
1019         COH_DBG(coh901318_list_print(cohc, lli));
1020
1021         /* Pick a descriptor to handle this transfer */
1022         cohd = coh901318_desc_get(cohc);
1023         cohd->lli = lli;
1024         cohd->flags = flags;
1025         cohd->desc.tx_submit = coh901318_tx_submit;
1026
1027         spin_unlock_irqrestore(&cohc->lock, flg);
1028
1029         return &cohd->desc;
1030  err:
1031         spin_unlock_irqrestore(&cohc->lock, flg);
1032         return NULL;
1033 }
1034
1035 static struct dma_async_tx_descriptor *
1036 coh901318_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
1037                         unsigned int sg_len, enum dma_data_direction direction,
1038                         unsigned long flags)
1039 {
1040         struct coh901318_chan *cohc = to_coh901318_chan(chan);
1041         struct coh901318_lli *lli;
1042         struct coh901318_desc *cohd;
1043         const struct coh901318_params *params;
1044         struct scatterlist *sg;
1045         int len = 0;
1046         int size;
1047         int i;
1048         u32 ctrl_chained = cohc_chan_param(cohc)->ctrl_lli_chained;
1049         u32 ctrl = cohc_chan_param(cohc)->ctrl_lli;
1050         u32 ctrl_last = cohc_chan_param(cohc)->ctrl_lli_last;
1051         u32 config;
1052         unsigned long flg;
1053         int ret;
1054
1055         if (!sgl)
1056                 goto out;
1057         if (sgl->length == 0)
1058                 goto out;
1059
1060         spin_lock_irqsave(&cohc->lock, flg);
1061
1062         dev_vdbg(COHC_2_DEV(cohc), "[%s] sg_len %d dir %d\n",
1063                  __func__, sg_len, direction);
1064
1065         if (flags & DMA_PREP_INTERRUPT)
1066                 /* Trigger interrupt after last lli */
1067                 ctrl_last |= COH901318_CX_CTRL_TC_IRQ_ENABLE;
1068
1069         params = cohc_chan_param(cohc);
1070         config = params->config;
1071         /*
1072          * Add runtime-specific control on top, make
1073          * sure the bits you set per peripheral channel are
1074          * cleared in the default config from the platform.
1075          */
1076         ctrl_chained |= cohc->runtime_ctrl;
1077         ctrl_last |= cohc->runtime_ctrl;
1078         ctrl |= cohc->runtime_ctrl;
1079
1080         if (direction == DMA_TO_DEVICE) {
1081                 u32 tx_flags = COH901318_CX_CTRL_PRDD_SOURCE |
1082                         COH901318_CX_CTRL_SRC_ADDR_INC_ENABLE;
1083
1084                 config |= COH901318_CX_CFG_RM_MEMORY_TO_PRIMARY;
1085                 ctrl_chained |= tx_flags;
1086                 ctrl_last |= tx_flags;
1087                 ctrl |= tx_flags;
1088         } else if (direction == DMA_FROM_DEVICE) {
1089                 u32 rx_flags = COH901318_CX_CTRL_PRDD_DEST |
1090                         COH901318_CX_CTRL_DST_ADDR_INC_ENABLE;
1091
1092                 config |= COH901318_CX_CFG_RM_PRIMARY_TO_MEMORY;
1093                 ctrl_chained |= rx_flags;
1094                 ctrl_last |= rx_flags;
1095                 ctrl |= rx_flags;
1096         } else
1097                 goto err_direction;
1098
1099         /* The dma only supports transmitting packages up to
1100          * MAX_DMA_PACKET_SIZE. Calculate to total number of
1101          * dma elemts required to send the entire sg list
1102          */
1103         for_each_sg(sgl, sg, sg_len, i) {
1104                 unsigned int factor;
1105                 size = sg_dma_len(sg);
1106
1107                 if (size <= MAX_DMA_PACKET_SIZE) {
1108                         len++;
1109                         continue;
1110                 }
1111
1112                 factor = size >> MAX_DMA_PACKET_SIZE_SHIFT;
1113                 if ((factor << MAX_DMA_PACKET_SIZE_SHIFT) < size)
1114                         factor++;
1115
1116                 len += factor;
1117         }
1118
1119         pr_debug("Allocate %d lli:s for this transfer\n", len);
1120         lli = coh901318_lli_alloc(&cohc->base->pool, len);
1121
1122         if (lli == NULL)
1123                 goto err_dma_alloc;
1124
1125         /* initiate allocated lli list */
1126         ret = coh901318_lli_fill_sg(&cohc->base->pool, lli, sgl, sg_len,
1127                                     cohc_dev_addr(cohc),
1128                                     ctrl_chained,
1129                                     ctrl,
1130                                     ctrl_last,
1131                                     direction, COH901318_CX_CTRL_TC_IRQ_ENABLE);
1132         if (ret)
1133                 goto err_lli_fill;
1134
1135
1136         COH_DBG(coh901318_list_print(cohc, lli));
1137
1138         /* Pick a descriptor to handle this transfer */
1139         cohd = coh901318_desc_get(cohc);
1140         cohd->head_config = config;
1141         /*
1142          * Set the default head ctrl for the channel to the one from the
1143          * lli, things may have changed due to odd buffer alignment
1144          * etc.
1145          */
1146         cohd->head_ctrl = lli->control;
1147         cohd->dir = direction;
1148         cohd->flags = flags;
1149         cohd->desc.tx_submit = coh901318_tx_submit;
1150         cohd->lli = lli;
1151
1152         spin_unlock_irqrestore(&cohc->lock, flg);
1153
1154         return &cohd->desc;
1155  err_lli_fill:
1156  err_dma_alloc:
1157  err_direction:
1158         spin_unlock_irqrestore(&cohc->lock, flg);
1159  out:
1160         return NULL;
1161 }
1162
1163 static enum dma_status
1164 coh901318_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
1165                  struct dma_tx_state *txstate)
1166 {
1167         struct coh901318_chan *cohc = to_coh901318_chan(chan);
1168         dma_cookie_t last_used;
1169         dma_cookie_t last_complete;
1170         int ret;
1171
1172         last_complete = cohc->completed;
1173         last_used = chan->cookie;
1174
1175         ret = dma_async_is_complete(cookie, last_complete, last_used);
1176
1177         dma_set_tx_state(txstate, last_complete, last_used,
1178                          coh901318_get_bytes_left(chan));
1179         if (ret == DMA_IN_PROGRESS && cohc->stopped)
1180                 ret = DMA_PAUSED;
1181
1182         return ret;
1183 }
1184
1185 static void
1186 coh901318_issue_pending(struct dma_chan *chan)
1187 {
1188         struct coh901318_chan *cohc = to_coh901318_chan(chan);
1189         unsigned long flags;
1190
1191         spin_lock_irqsave(&cohc->lock, flags);
1192
1193         /*
1194          * Busy means that pending jobs are already being processed,
1195          * and then there is no point in starting the queue: the
1196          * terminal count interrupt on the channel will take the next
1197          * job on the queue and execute it anyway.
1198          */
1199         if (!cohc->busy)
1200                 coh901318_queue_start(cohc);
1201
1202         spin_unlock_irqrestore(&cohc->lock, flags);
1203 }
1204
1205 /*
1206  * Here we wrap in the runtime dma control interface
1207  */
1208 struct burst_table {
1209         int burst_8bit;
1210         int burst_16bit;
1211         int burst_32bit;
1212         u32 reg;
1213 };
1214
1215 static const struct burst_table burst_sizes[] = {
1216         {
1217                 .burst_8bit = 64,
1218                 .burst_16bit = 32,
1219                 .burst_32bit = 16,
1220                 .reg = COH901318_CX_CTRL_BURST_COUNT_64_BYTES,
1221         },
1222         {
1223                 .burst_8bit = 48,
1224                 .burst_16bit = 24,
1225                 .burst_32bit = 12,
1226                 .reg = COH901318_CX_CTRL_BURST_COUNT_48_BYTES,
1227         },
1228         {
1229                 .burst_8bit = 32,
1230                 .burst_16bit = 16,
1231                 .burst_32bit = 8,
1232                 .reg = COH901318_CX_CTRL_BURST_COUNT_32_BYTES,
1233         },
1234         {
1235                 .burst_8bit = 16,
1236                 .burst_16bit = 8,
1237                 .burst_32bit = 4,
1238                 .reg = COH901318_CX_CTRL_BURST_COUNT_16_BYTES,
1239         },
1240         {
1241                 .burst_8bit = 8,
1242                 .burst_16bit = 4,
1243                 .burst_32bit = 2,
1244                 .reg = COH901318_CX_CTRL_BURST_COUNT_8_BYTES,
1245         },
1246         {
1247                 .burst_8bit = 4,
1248                 .burst_16bit = 2,
1249                 .burst_32bit = 1,
1250                 .reg = COH901318_CX_CTRL_BURST_COUNT_4_BYTES,
1251         },
1252         {
1253                 .burst_8bit = 2,
1254                 .burst_16bit = 1,
1255                 .burst_32bit = 0,
1256                 .reg = COH901318_CX_CTRL_BURST_COUNT_2_BYTES,
1257         },
1258         {
1259                 .burst_8bit = 1,
1260                 .burst_16bit = 0,
1261                 .burst_32bit = 0,
1262                 .reg = COH901318_CX_CTRL_BURST_COUNT_1_BYTE,
1263         },
1264 };
1265
1266 static void coh901318_dma_set_runtimeconfig(struct dma_chan *chan,
1267                         struct dma_slave_config *config)
1268 {
1269         struct coh901318_chan *cohc = to_coh901318_chan(chan);
1270         dma_addr_t addr;
1271         enum dma_slave_buswidth addr_width;
1272         u32 maxburst;
1273         u32 runtime_ctrl = 0;
1274         int i = 0;
1275
1276         /* We only support mem to per or per to mem transfers */
1277         if (config->direction == DMA_FROM_DEVICE) {
1278                 addr = config->src_addr;
1279                 addr_width = config->src_addr_width;
1280                 maxburst = config->src_maxburst;
1281         } else if (config->direction == DMA_TO_DEVICE) {
1282                 addr = config->dst_addr;
1283                 addr_width = config->dst_addr_width;
1284                 maxburst = config->dst_maxburst;
1285         } else {
1286                 dev_err(COHC_2_DEV(cohc), "illegal channel mode\n");
1287                 return;
1288         }
1289
1290         dev_dbg(COHC_2_DEV(cohc), "configure channel for %d byte transfers\n",
1291                 addr_width);
1292         switch (addr_width)  {
1293         case DMA_SLAVE_BUSWIDTH_1_BYTE:
1294                 runtime_ctrl |=
1295                         COH901318_CX_CTRL_SRC_BUS_SIZE_8_BITS |
1296                         COH901318_CX_CTRL_DST_BUS_SIZE_8_BITS;
1297
1298                 while (i < ARRAY_SIZE(burst_sizes)) {
1299                         if (burst_sizes[i].burst_8bit <= maxburst)
1300                                 break;
1301                         i++;
1302                 }
1303
1304                 break;
1305         case DMA_SLAVE_BUSWIDTH_2_BYTES:
1306                 runtime_ctrl |=
1307                         COH901318_CX_CTRL_SRC_BUS_SIZE_16_BITS |
1308                         COH901318_CX_CTRL_DST_BUS_SIZE_16_BITS;
1309
1310                 while (i < ARRAY_SIZE(burst_sizes)) {
1311                         if (burst_sizes[i].burst_16bit <= maxburst)
1312                                 break;
1313                         i++;
1314                 }
1315
1316                 break;
1317         case DMA_SLAVE_BUSWIDTH_4_BYTES:
1318                 /* Direction doesn't matter here, it's 32/32 bits */
1319                 runtime_ctrl |=
1320                         COH901318_CX_CTRL_SRC_BUS_SIZE_32_BITS |
1321                         COH901318_CX_CTRL_DST_BUS_SIZE_32_BITS;
1322
1323                 while (i < ARRAY_SIZE(burst_sizes)) {
1324                         if (burst_sizes[i].burst_32bit <= maxburst)
1325                                 break;
1326                         i++;
1327                 }
1328
1329                 break;
1330         default:
1331                 dev_err(COHC_2_DEV(cohc),
1332                         "bad runtimeconfig: alien address width\n");
1333                 return;
1334         }
1335
1336         runtime_ctrl |= burst_sizes[i].reg;
1337         dev_dbg(COHC_2_DEV(cohc),
1338                 "selected burst size %d bytes for address width %d bytes, maxburst %d\n",
1339                 burst_sizes[i].burst_8bit, addr_width, maxburst);
1340
1341         cohc->runtime_addr = addr;
1342         cohc->runtime_ctrl = runtime_ctrl;
1343 }
1344
1345 static int
1346 coh901318_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
1347                   unsigned long arg)
1348 {
1349         unsigned long flags;
1350         struct coh901318_chan *cohc = to_coh901318_chan(chan);
1351         struct coh901318_desc *cohd;
1352         void __iomem *virtbase = cohc->base->virtbase;
1353
1354         if (cmd == DMA_SLAVE_CONFIG) {
1355                 struct dma_slave_config *config =
1356                         (struct dma_slave_config *) arg;
1357
1358                 coh901318_dma_set_runtimeconfig(chan, config);
1359                 return 0;
1360           }
1361
1362         if (cmd == DMA_PAUSE) {
1363                 coh901318_pause(chan);
1364                 return 0;
1365         }
1366
1367         if (cmd == DMA_RESUME) {
1368                 coh901318_resume(chan);
1369                 return 0;
1370         }
1371
1372         if (cmd != DMA_TERMINATE_ALL)
1373                 return -ENXIO;
1374
1375         /* The remainder of this function terminates the transfer */
1376         coh901318_pause(chan);
1377         spin_lock_irqsave(&cohc->lock, flags);
1378
1379         /* Clear any pending BE or TC interrupt */
1380         if (cohc->id < 32) {
1381                 writel(1 << cohc->id, virtbase + COH901318_BE_INT_CLEAR1);
1382                 writel(1 << cohc->id, virtbase + COH901318_TC_INT_CLEAR1);
1383         } else {
1384                 writel(1 << (cohc->id - 32), virtbase +
1385                        COH901318_BE_INT_CLEAR2);
1386                 writel(1 << (cohc->id - 32), virtbase +
1387                        COH901318_TC_INT_CLEAR2);
1388         }
1389
1390         enable_powersave(cohc);
1391
1392         while ((cohd = coh901318_first_active_get(cohc))) {
1393                 /* release the lli allocation*/
1394                 coh901318_lli_free(&cohc->base->pool, &cohd->lli);
1395
1396                 /* return desc to free-list */
1397                 coh901318_desc_remove(cohd);
1398                 coh901318_desc_free(cohc, cohd);
1399         }
1400
1401         while ((cohd = coh901318_first_queued(cohc))) {
1402                 /* release the lli allocation*/
1403                 coh901318_lli_free(&cohc->base->pool, &cohd->lli);
1404
1405                 /* return desc to free-list */
1406                 coh901318_desc_remove(cohd);
1407                 coh901318_desc_free(cohc, cohd);
1408         }
1409
1410
1411         cohc->nbr_active_done = 0;
1412         cohc->busy = 0;
1413
1414         spin_unlock_irqrestore(&cohc->lock, flags);
1415
1416         return 0;
1417 }
1418
1419 void coh901318_base_init(struct dma_device *dma, const int *pick_chans,
1420                          struct coh901318_base *base)
1421 {
1422         int chans_i;
1423         int i = 0;
1424         struct coh901318_chan *cohc;
1425
1426         INIT_LIST_HEAD(&dma->channels);
1427
1428         for (chans_i = 0; pick_chans[chans_i] != -1; chans_i += 2) {
1429                 for (i = pick_chans[chans_i]; i <= pick_chans[chans_i+1]; i++) {
1430                         cohc = &base->chans[i];
1431
1432                         cohc->base = base;
1433                         cohc->chan.device = dma;
1434                         cohc->id = i;
1435
1436                         /* TODO: do we really need this lock if only one
1437                          * client is connected to each channel?
1438                          */
1439
1440                         spin_lock_init(&cohc->lock);
1441
1442                         cohc->nbr_active_done = 0;
1443                         cohc->busy = 0;
1444                         INIT_LIST_HEAD(&cohc->free);
1445                         INIT_LIST_HEAD(&cohc->active);
1446                         INIT_LIST_HEAD(&cohc->queue);
1447
1448                         tasklet_init(&cohc->tasklet, dma_tasklet,
1449                                      (unsigned long) cohc);
1450
1451                         list_add_tail(&cohc->chan.device_node,
1452                                       &dma->channels);
1453                 }
1454         }
1455 }
1456
1457 static int __init coh901318_probe(struct platform_device *pdev)
1458 {
1459         int err = 0;
1460         struct coh901318_platform *pdata;
1461         struct coh901318_base *base;
1462         int irq;
1463         struct resource *io;
1464
1465         io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1466         if (!io)
1467                 goto err_get_resource;
1468
1469         /* Map DMA controller registers to virtual memory */
1470         if (request_mem_region(io->start,
1471                                resource_size(io),
1472                                pdev->dev.driver->name) == NULL) {
1473                 err = -EBUSY;
1474                 goto err_request_mem;
1475         }
1476
1477         pdata = pdev->dev.platform_data;
1478         if (!pdata)
1479                 goto err_no_platformdata;
1480
1481         base = kmalloc(ALIGN(sizeof(struct coh901318_base), 4) +
1482                        pdata->max_channels *
1483                        sizeof(struct coh901318_chan),
1484                        GFP_KERNEL);
1485         if (!base)
1486                 goto err_alloc_coh_dma_channels;
1487
1488         base->chans = ((void *)base) + ALIGN(sizeof(struct coh901318_base), 4);
1489
1490         base->virtbase = ioremap(io->start, resource_size(io));
1491         if (!base->virtbase) {
1492                 err = -ENOMEM;
1493                 goto err_no_ioremap;
1494         }
1495
1496         base->dev = &pdev->dev;
1497         base->platform = pdata;
1498         spin_lock_init(&base->pm.lock);
1499         base->pm.started_channels = 0;
1500
1501         COH901318_DEBUGFS_ASSIGN(debugfs_dma_base, base);
1502
1503         platform_set_drvdata(pdev, base);
1504
1505         irq = platform_get_irq(pdev, 0);
1506         if (irq < 0)
1507                 goto err_no_irq;
1508
1509         err = request_irq(irq, dma_irq_handler, IRQF_DISABLED,
1510                           "coh901318", base);
1511         if (err) {
1512                 dev_crit(&pdev->dev,
1513                          "Cannot allocate IRQ for DMA controller!\n");
1514                 goto err_request_irq;
1515         }
1516
1517         err = coh901318_pool_create(&base->pool, &pdev->dev,
1518                                     sizeof(struct coh901318_lli),
1519                                     32);
1520         if (err)
1521                 goto err_pool_create;
1522
1523         /* init channels for device transfers */
1524         coh901318_base_init(&base->dma_slave,  base->platform->chans_slave,
1525                             base);
1526
1527         dma_cap_zero(base->dma_slave.cap_mask);
1528         dma_cap_set(DMA_SLAVE, base->dma_slave.cap_mask);
1529
1530         base->dma_slave.device_alloc_chan_resources = coh901318_alloc_chan_resources;
1531         base->dma_slave.device_free_chan_resources = coh901318_free_chan_resources;
1532         base->dma_slave.device_prep_slave_sg = coh901318_prep_slave_sg;
1533         base->dma_slave.device_tx_status = coh901318_tx_status;
1534         base->dma_slave.device_issue_pending = coh901318_issue_pending;
1535         base->dma_slave.device_control = coh901318_control;
1536         base->dma_slave.dev = &pdev->dev;
1537
1538         err = dma_async_device_register(&base->dma_slave);
1539
1540         if (err)
1541                 goto err_register_slave;
1542
1543         /* init channels for memcpy */
1544         coh901318_base_init(&base->dma_memcpy, base->platform->chans_memcpy,
1545                             base);
1546
1547         dma_cap_zero(base->dma_memcpy.cap_mask);
1548         dma_cap_set(DMA_MEMCPY, base->dma_memcpy.cap_mask);
1549
1550         base->dma_memcpy.device_alloc_chan_resources = coh901318_alloc_chan_resources;
1551         base->dma_memcpy.device_free_chan_resources = coh901318_free_chan_resources;
1552         base->dma_memcpy.device_prep_dma_memcpy = coh901318_prep_memcpy;
1553         base->dma_memcpy.device_tx_status = coh901318_tx_status;
1554         base->dma_memcpy.device_issue_pending = coh901318_issue_pending;
1555         base->dma_memcpy.device_control = coh901318_control;
1556         base->dma_memcpy.dev = &pdev->dev;
1557         /*
1558          * This controller can only access address at even 32bit boundaries,
1559          * i.e. 2^2
1560          */
1561         base->dma_memcpy.copy_align = 2;
1562         err = dma_async_device_register(&base->dma_memcpy);
1563
1564         if (err)
1565                 goto err_register_memcpy;
1566
1567         dev_info(&pdev->dev, "Initialized COH901318 DMA on virtual base 0x%08x\n",
1568                 (u32) base->virtbase);
1569
1570         return err;
1571
1572  err_register_memcpy:
1573         dma_async_device_unregister(&base->dma_slave);
1574  err_register_slave:
1575         coh901318_pool_destroy(&base->pool);
1576  err_pool_create:
1577         free_irq(platform_get_irq(pdev, 0), base);
1578  err_request_irq:
1579  err_no_irq:
1580         iounmap(base->virtbase);
1581  err_no_ioremap:
1582         kfree(base);
1583  err_alloc_coh_dma_channels:
1584  err_no_platformdata:
1585         release_mem_region(pdev->resource->start,
1586                            resource_size(pdev->resource));
1587  err_request_mem:
1588  err_get_resource:
1589         return err;
1590 }
1591
1592 static int __exit coh901318_remove(struct platform_device *pdev)
1593 {
1594         struct coh901318_base *base = platform_get_drvdata(pdev);
1595
1596         dma_async_device_unregister(&base->dma_memcpy);
1597         dma_async_device_unregister(&base->dma_slave);
1598         coh901318_pool_destroy(&base->pool);
1599         free_irq(platform_get_irq(pdev, 0), base);
1600         iounmap(base->virtbase);
1601         kfree(base);
1602         release_mem_region(pdev->resource->start,
1603                            resource_size(pdev->resource));
1604         return 0;
1605 }
1606
1607
1608 static struct platform_driver coh901318_driver = {
1609         .remove = __exit_p(coh901318_remove),
1610         .driver = {
1611                 .name   = "coh901318",
1612         },
1613 };
1614
1615 int __init coh901318_init(void)
1616 {
1617         return platform_driver_probe(&coh901318_driver, coh901318_probe);
1618 }
1619 subsys_initcall(coh901318_init);
1620
1621 void __exit coh901318_exit(void)
1622 {
1623         platform_driver_unregister(&coh901318_driver);
1624 }
1625 module_exit(coh901318_exit);
1626
1627 MODULE_LICENSE("GPL");
1628 MODULE_AUTHOR("Per Friden");