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