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