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