drivers/dma/sh/shdma.c

   1 /*
   2  * Renesas SuperH DMA Engine support
   3  *
   4  * base is drivers/dma/flsdma.c
   5  *
   6  * Copyright (C) 2011-2012 Guennadi Liakhovetski <[email protected]>
   7  * Copyright (C) 2009 Nobuhiro Iwamatsu <[email protected]>
   8  * Copyright (C) 2009 Renesas Solutions, Inc. All rights reserved.
   9  * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
  10  *
  11  * This is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * - DMA of SuperH does not have Hardware DMA chain mode.
  17  * - MAX DMA size is 16MB.
  18  *
  19  */
  20
  21 #include <linux/init.h>
  22 #include <linux/module.h>
  23 #include <linux/slab.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/dmaengine.h>
  26 #include <linux/delay.h>
  27 #include <linux/platform_device.h>
  28 #include <linux/pm_runtime.h>
  29 #include <linux/sh_dma.h>
  30 #include <linux/notifier.h>
  31 #include <linux/kdebug.h>
  32 #include <linux/spinlock.h>
  33 #include <linux/rculist.h>
  34
  35 #include "../dmaengine.h"
  36 #include "shdma.h"
  37
  38 #define SH_DMAE_DRV_NAME "sh-dma-engine"
  39
  40 /* Default MEMCPY transfer size = 2^2 = 4 bytes */
  41 #define LOG2_DEFAULT_XFER_SIZE  2
  42 #define SH_DMA_SLAVE_NUMBER 256
  43 #define SH_DMA_TCR_MAX (16 * 1024 * 1024 - 1)
  44
  45 /*
  46  * Used for write-side mutual exclusion for the global device list,
  47  * read-side synchronization by way of RCU, and per-controller data.
  48  */
  49 static DEFINE_SPINLOCK(sh_dmae_lock);
  50 static LIST_HEAD(sh_dmae_devices);
  51
  52 static void chclr_write(struct sh_dmae_chan *sh_dc, u32 data)
  53 {
  54         struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
  55
  56         __raw_writel(data, shdev->chan_reg +
  57                      shdev->pdata->channel[sh_dc->shdma_chan.id].chclr_offset);
  58 }
  59
  60 static void sh_dmae_writel(struct sh_dmae_chan *sh_dc, u32 data, u32 reg)
  61 {
  62         __raw_writel(data, sh_dc->base + reg / sizeof(u32));
  63 }
  64
  65 static u32 sh_dmae_readl(struct sh_dmae_chan *sh_dc, u32 reg)
  66 {
  67         return __raw_readl(sh_dc->base + reg / sizeof(u32));
  68 }
  69
  70 static u16 dmaor_read(struct sh_dmae_device *shdev)
  71 {
  72         u32 __iomem *addr = shdev->chan_reg + DMAOR / sizeof(u32);
  73
  74         if (shdev->pdata->dmaor_is_32bit)
  75                 return __raw_readl(addr);
  76         else
  77                 return __raw_readw(addr);
  78 }
  79
  80 static void dmaor_write(struct sh_dmae_device *shdev, u16 data)
  81 {
  82         u32 __iomem *addr = shdev->chan_reg + DMAOR / sizeof(u32);
  83
  84         if (shdev->pdata->dmaor_is_32bit)
  85                 __raw_writel(data, addr);
  86         else
  87                 __raw_writew(data, addr);
  88 }
  89
  90 static void chcr_write(struct sh_dmae_chan *sh_dc, u32 data)
  91 {
  92         struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
  93
  94         __raw_writel(data, sh_dc->base + shdev->chcr_offset / sizeof(u32));
  95 }
  96
  97 static u32 chcr_read(struct sh_dmae_chan *sh_dc)
  98 {
  99         struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
 100
 101         return __raw_readl(sh_dc->base + shdev->chcr_offset / sizeof(u32));
 102 }
 103
 104 /*
 105  * Reset DMA controller
 106  *
 107  * SH7780 has two DMAOR register
 108  */
 109 static void sh_dmae_ctl_stop(struct sh_dmae_device *shdev)
 110 {
 111         unsigned short dmaor;
 112         unsigned long flags;
 113
 114         spin_lock_irqsave(&sh_dmae_lock, flags);
 115
 116         dmaor = dmaor_read(shdev);
 117         dmaor_write(shdev, dmaor & ~(DMAOR_NMIF | DMAOR_AE | DMAOR_DME));
 118
 119         spin_unlock_irqrestore(&sh_dmae_lock, flags);
 120 }
 121
 122 static int sh_dmae_rst(struct sh_dmae_device *shdev)
 123 {
 124         unsigned short dmaor;
 125         unsigned long flags;
 126
 127         spin_lock_irqsave(&sh_dmae_lock, flags);
 128
 129         dmaor = dmaor_read(shdev) & ~(DMAOR_NMIF | DMAOR_AE | DMAOR_DME);
 130
 131         if (shdev->pdata->chclr_present) {
 132                 int i;
 133                 for (i = 0; i < shdev->pdata->channel_num; i++) {
 134                         struct sh_dmae_chan *sh_chan = shdev->chan[i];
 135                         if (sh_chan)
 136                                 chclr_write(sh_chan, 0);
 137                 }
 138         }
 139
 140         dmaor_write(shdev, dmaor | shdev->pdata->dmaor_init);
 141
 142         dmaor = dmaor_read(shdev);
 143
 144         spin_unlock_irqrestore(&sh_dmae_lock, flags);
 145
 146         if (dmaor & (DMAOR_AE | DMAOR_NMIF)) {
 147                 dev_warn(shdev->shdma_dev.dma_dev.dev, "Can't initialize DMAOR.\n");
 148                 return -EIO;
 149         }
 150         if (shdev->pdata->dmaor_init & ~dmaor)
 151                 dev_warn(shdev->shdma_dev.dma_dev.dev,
 152                          "DMAOR=0x%x hasn't latched the initial value 0x%x.\n",
 153                          dmaor, shdev->pdata->dmaor_init);
 154         return 0;
 155 }
 156
 157 static bool dmae_is_busy(struct sh_dmae_chan *sh_chan)
 158 {
 159         u32 chcr = chcr_read(sh_chan);
 160
 161         if ((chcr & (CHCR_DE | CHCR_TE)) == CHCR_DE)
 162                 return true; /* working */
 163
 164         return false; /* waiting */
 165 }
 166
 167 static unsigned int calc_xmit_shift(struct sh_dmae_chan *sh_chan, u32 chcr)
 168 {
 169         struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
 170         struct sh_dmae_pdata *pdata = shdev->pdata;
 171         int cnt = ((chcr & pdata->ts_low_mask) >> pdata->ts_low_shift) |
 172                 ((chcr & pdata->ts_high_mask) >> pdata->ts_high_shift);
 173
 174         if (cnt >= pdata->ts_shift_num)
 175                 cnt = 0;
 176
 177         return pdata->ts_shift[cnt];
 178 }
 179
 180 static u32 log2size_to_chcr(struct sh_dmae_chan *sh_chan, int l2size)
 181 {
 182         struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
 183         struct sh_dmae_pdata *pdata = shdev->pdata;
 184         int i;
 185
 186         for (i = 0; i < pdata->ts_shift_num; i++)
 187                 if (pdata->ts_shift[i] == l2size)
 188                         break;
 189
 190         if (i == pdata->ts_shift_num)
 191                 i = 0;
 192
 193         return ((i << pdata->ts_low_shift) & pdata->ts_low_mask) |
 194                 ((i << pdata->ts_high_shift) & pdata->ts_high_mask);
 195 }
 196
 197 static void dmae_set_reg(struct sh_dmae_chan *sh_chan, struct sh_dmae_regs *hw)
 198 {
 199         sh_dmae_writel(sh_chan, hw->sar, SAR);
 200         sh_dmae_writel(sh_chan, hw->dar, DAR);
 201         sh_dmae_writel(sh_chan, hw->tcr >> sh_chan->xmit_shift, TCR);
 202 }
 203
 204 static void dmae_start(struct sh_dmae_chan *sh_chan)
 205 {
 206         struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
 207         u32 chcr = chcr_read(sh_chan);
 208
 209         if (shdev->pdata->needs_tend_set)
 210                 sh_dmae_writel(sh_chan, 0xFFFFFFFF, TEND);
 211
 212         chcr |= CHCR_DE | shdev->chcr_ie_bit;
 213         chcr_write(sh_chan, chcr & ~CHCR_TE);
 214 }
 215
 216 static void dmae_init(struct sh_dmae_chan *sh_chan)
 217 {
 218         /*
 219          * Default configuration for dual address memory-memory transfer.
 220          * 0x400 represents auto-request.
 221          */
 222         u32 chcr = DM_INC | SM_INC | 0x400 | log2size_to_chcr(sh_chan,
 223                                                    LOG2_DEFAULT_XFER_SIZE);
 224         sh_chan->xmit_shift = calc_xmit_shift(sh_chan, chcr);
 225         chcr_write(sh_chan, chcr);
 226 }
 227
 228 static int dmae_set_chcr(struct sh_dmae_chan *sh_chan, u32 val)
 229 {
 230         /* If DMA is active, cannot set CHCR. TODO: remove this superfluous check */
 231         if (dmae_is_busy(sh_chan))
 232                 return -EBUSY;
 233
 234         sh_chan->xmit_shift = calc_xmit_shift(sh_chan, val);
 235         chcr_write(sh_chan, val);
 236
 237         return 0;
 238 }
 239
 240 static int dmae_set_dmars(struct sh_dmae_chan *sh_chan, u16 val)
 241 {
 242         struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
 243         struct sh_dmae_pdata *pdata = shdev->pdata;
 244         const struct sh_dmae_channel *chan_pdata = &pdata->channel[sh_chan->shdma_chan.id];
 245         u16 __iomem *addr = shdev->dmars;
 246         unsigned int shift = chan_pdata->dmars_bit;
 247
 248         if (dmae_is_busy(sh_chan))
 249                 return -EBUSY;
 250
 251         if (pdata->no_dmars)
 252                 return 0;
 253
 254         /* in the case of a missing DMARS resource use first memory window */
 255         if (!addr)
 256                 addr = (u16 __iomem *)shdev->chan_reg;
 257         addr += chan_pdata->dmars / sizeof(u16);
 258
 259         __raw_writew((__raw_readw(addr) & (0xff00 >> shift)) | (val << shift),
 260                      addr);
 261
 262         return 0;
 263 }
 264
 265 static void sh_dmae_start_xfer(struct shdma_chan *schan,
 266                                struct shdma_desc *sdesc)
 267 {
 268         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
 269                                                     shdma_chan);
 270         struct sh_dmae_desc *sh_desc = container_of(sdesc,
 271                                         struct sh_dmae_desc, shdma_desc);
 272         dev_dbg(sh_chan->shdma_chan.dev, "Queue #%d to %d: %u@%x -> %x\n",
 273                 sdesc->async_tx.cookie, sh_chan->shdma_chan.id,
 274                 sh_desc->hw.tcr, sh_desc->hw.sar, sh_desc->hw.dar);
 275         /* Get the ld start address from ld_queue */
 276         dmae_set_reg(sh_chan, &sh_desc->hw);
 277         dmae_start(sh_chan);
 278 }
 279
 280 static bool sh_dmae_channel_busy(struct shdma_chan *schan)
 281 {
 282         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
 283                                                     shdma_chan);
 284         return dmae_is_busy(sh_chan);
 285 }
 286
 287 static void sh_dmae_setup_xfer(struct shdma_chan *schan,
 288                                int slave_id)
 289 {
 290         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
 291                                                     shdma_chan);
 292
 293         if (slave_id >= 0) {
 294                 const struct sh_dmae_slave_config *cfg =
 295                         sh_chan->config;
 296
 297                 dmae_set_dmars(sh_chan, cfg->mid_rid);
 298                 dmae_set_chcr(sh_chan, cfg->chcr);
 299         } else {
 300                 dmae_init(sh_chan);
 301         }
 302 }
 303
 304 /*
 305  * Find a slave channel configuration from the contoller list by either a slave
 306  * ID in the non-DT case, or by a MID/RID value in the DT case
 307  */
 308 static const struct sh_dmae_slave_config *dmae_find_slave(
 309         struct sh_dmae_chan *sh_chan, int match)
 310 {
 311         struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
 312         struct sh_dmae_pdata *pdata = shdev->pdata;
 313         const struct sh_dmae_slave_config *cfg;
 314         int i;
 315
 316         if (!sh_chan->shdma_chan.dev->of_node) {
 317                 if (match >= SH_DMA_SLAVE_NUMBER)
 318                         return NULL;
 319
 320                 for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++)
 321                         if (cfg->slave_id == match)
 322                                 return cfg;
 323         } else {
 324                 for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++)
 325                         if (cfg->mid_rid == match) {
 326                                 sh_chan->shdma_chan.slave_id = cfg->slave_id;
 327                                 return cfg;
 328                         }
 329         }
 330
 331         return NULL;
 332 }
 333
 334 static int sh_dmae_set_slave(struct shdma_chan *schan,
 335                              int slave_id, bool try)
 336 {
 337         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
 338                                                     shdma_chan);
 339         const struct sh_dmae_slave_config *cfg = dmae_find_slave(sh_chan, slave_id);
 340         if (!cfg)
 341                 return -ENXIO;
 342
 343         if (!try)
 344                 sh_chan->config = cfg;
 345
 346         return 0;
 347 }
 348
 349 static void dmae_halt(struct sh_dmae_chan *sh_chan)
 350 {
 351         struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
 352         u32 chcr = chcr_read(sh_chan);
 353
 354         chcr &= ~(CHCR_DE | CHCR_TE | shdev->chcr_ie_bit);
 355         chcr_write(sh_chan, chcr);
 356 }
 357
 358 static int sh_dmae_desc_setup(struct shdma_chan *schan,
 359                               struct shdma_desc *sdesc,
 360                               dma_addr_t src, dma_addr_t dst, size_t *len)
 361 {
 362         struct sh_dmae_desc *sh_desc = container_of(sdesc,
 363                                         struct sh_dmae_desc, shdma_desc);
 364
 365         if (*len > schan->max_xfer_len)
 366                 *len = schan->max_xfer_len;
 367
 368         sh_desc->hw.sar = src;
 369         sh_desc->hw.dar = dst;
 370         sh_desc->hw.tcr = *len;
 371
 372         return 0;
 373 }
 374
 375 static void sh_dmae_halt(struct shdma_chan *schan)
 376 {
 377         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
 378                                                     shdma_chan);
 379         dmae_halt(sh_chan);
 380 }
 381
 382 static bool sh_dmae_chan_irq(struct shdma_chan *schan, int irq)
 383 {
 384         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
 385                                                     shdma_chan);
 386
 387         if (!(chcr_read(sh_chan) & CHCR_TE))
 388                 return false;
 389
 390         /* DMA stop */
 391         dmae_halt(sh_chan);
 392
 393         return true;
 394 }
 395
 396 static size_t sh_dmae_get_partial(struct shdma_chan *schan,
 397                                   struct shdma_desc *sdesc)
 398 {
 399         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
 400                                                     shdma_chan);
 401         struct sh_dmae_desc *sh_desc = container_of(sdesc,
 402                                         struct sh_dmae_desc, shdma_desc);
 403         return sh_desc->hw.tcr -
 404                 (sh_dmae_readl(sh_chan, TCR) << sh_chan->xmit_shift);
 405 }
 406
 407 /* Called from error IRQ or NMI */
 408 static bool sh_dmae_reset(struct sh_dmae_device *shdev)
 409 {
 410         bool ret;
 411
 412         /* halt the dma controller */
 413         sh_dmae_ctl_stop(shdev);
 414
 415         /* We cannot detect, which channel caused the error, have to reset all */
 416         ret = shdma_reset(&shdev->shdma_dev);
 417
 418         sh_dmae_rst(shdev);
 419
 420         return ret;
 421 }
 422
 423 static irqreturn_t sh_dmae_err(int irq, void *data)
 424 {
 425         struct sh_dmae_device *shdev = data;
 426
 427         if (!(dmaor_read(shdev) & DMAOR_AE))
 428                 return IRQ_NONE;
 429
 430         sh_dmae_reset(shdev);
 431         return IRQ_HANDLED;
 432 }
 433
 434 static bool sh_dmae_desc_completed(struct shdma_chan *schan,
 435                                    struct shdma_desc *sdesc)
 436 {
 437         struct sh_dmae_chan *sh_chan = container_of(schan,
 438                                         struct sh_dmae_chan, shdma_chan);
 439         struct sh_dmae_desc *sh_desc = container_of(sdesc,
 440                                         struct sh_dmae_desc, shdma_desc);
 441         u32 sar_buf = sh_dmae_readl(sh_chan, SAR);
 442         u32 dar_buf = sh_dmae_readl(sh_chan, DAR);
 443
 444         return  (sdesc->direction == DMA_DEV_TO_MEM &&
 445                  (sh_desc->hw.dar + sh_desc->hw.tcr) == dar_buf) ||
 446                 (sdesc->direction != DMA_DEV_TO_MEM &&
 447                  (sh_desc->hw.sar + sh_desc->hw.tcr) == sar_buf);
 448 }
 449
 450 static bool sh_dmae_nmi_notify(struct sh_dmae_device *shdev)
 451 {
 452         /* Fast path out if NMIF is not asserted for this controller */
 453         if ((dmaor_read(shdev) & DMAOR_NMIF) == 0)
 454                 return false;
 455
 456         return sh_dmae_reset(shdev);
 457 }
 458
 459 static int sh_dmae_nmi_handler(struct notifier_block *self,
 460                                unsigned long cmd, void *data)
 461 {
 462         struct sh_dmae_device *shdev;
 463         int ret = NOTIFY_DONE;
 464         bool triggered;
 465
 466         /*
 467          * Only concern ourselves with NMI events.
 468          *
 469          * Normally we would check the die chain value, but as this needs
 470          * to be architecture independent, check for NMI context instead.
 471          */
 472         if (!in_nmi())
 473                 return NOTIFY_DONE;
 474
 475         rcu_read_lock();
 476         list_for_each_entry_rcu(shdev, &sh_dmae_devices, node) {
 477                 /*
 478                  * Only stop if one of the controllers has NMIF asserted,
 479                  * we do not want to interfere with regular address error
 480                  * handling or NMI events that don't concern the DMACs.
 481                  */
 482                 triggered = sh_dmae_nmi_notify(shdev);
 483                 if (triggered == true)
 484                         ret = NOTIFY_OK;
 485         }
 486         rcu_read_unlock();
 487
 488         return ret;
 489 }
 490
 491 static struct notifier_block sh_dmae_nmi_notifier __read_mostly = {
 492         .notifier_call  = sh_dmae_nmi_handler,
 493
 494         /* Run before NMI debug handler and KGDB */
 495         .priority       = 1,
 496 };
 497
 498 static int sh_dmae_chan_probe(struct sh_dmae_device *shdev, int id,
 499                                         int irq, unsigned long flags)
 500 {
 501         const struct sh_dmae_channel *chan_pdata = &shdev->pdata->channel[id];
 502         struct shdma_dev *sdev = &shdev->shdma_dev;
 503         struct platform_device *pdev = to_platform_device(sdev->dma_dev.dev);
 504         struct sh_dmae_chan *sh_chan;
 505         struct shdma_chan *schan;
 506         int err;
 507
 508         sh_chan = kzalloc(sizeof(struct sh_dmae_chan), GFP_KERNEL);
 509         if (!sh_chan) {
 510                 dev_err(sdev->dma_dev.dev,
 511                         "No free memory for allocating dma channels!\n");
 512                 return -ENOMEM;
 513         }
 514
 515         schan = &sh_chan->shdma_chan;
 516         schan->max_xfer_len = SH_DMA_TCR_MAX + 1;
 517
 518         shdma_chan_probe(sdev, schan, id);
 519
 520         sh_chan->base = shdev->chan_reg + chan_pdata->offset / sizeof(u32);
 521
 522         /* set up channel irq */
 523         if (pdev->id >= 0)
 524                 snprintf(sh_chan->dev_id, sizeof(sh_chan->dev_id),
 525                          "sh-dmae%d.%d", pdev->id, id);
 526         else
 527                 snprintf(sh_chan->dev_id, sizeof(sh_chan->dev_id),
 528                          "sh-dma%d", id);
 529
 530         err = shdma_request_irq(schan, irq, flags, sh_chan->dev_id);
 531         if (err) {
 532                 dev_err(sdev->dma_dev.dev,
 533                         "DMA channel %d request_irq error %d\n",
 534                         id, err);
 535                 goto err_no_irq;
 536         }
 537
 538         shdev->chan[id] = sh_chan;
 539         return 0;
 540
 541 err_no_irq:
 542         /* remove from dmaengine device node */
 543         shdma_chan_remove(schan);
 544         kfree(sh_chan);
 545         return err;
 546 }
 547
 548 static void sh_dmae_chan_remove(struct sh_dmae_device *shdev)
 549 {
 550         struct dma_device *dma_dev = &shdev->shdma_dev.dma_dev;
 551         struct shdma_chan *schan;
 552         int i;
 553
 554         shdma_for_each_chan(schan, &shdev->shdma_dev, i) {
 555                 struct sh_dmae_chan *sh_chan = container_of(schan,
 556                                         struct sh_dmae_chan, shdma_chan);
 557                 BUG_ON(!schan);
 558
 559                 shdma_free_irq(&sh_chan->shdma_chan);
 560
 561                 shdma_chan_remove(schan);
 562                 kfree(sh_chan);
 563         }
 564         dma_dev->chancnt = 0;
 565 }
 566
 567 static void sh_dmae_shutdown(struct platform_device *pdev)
 568 {
 569         struct sh_dmae_device *shdev = platform_get_drvdata(pdev);
 570         sh_dmae_ctl_stop(shdev);
 571 }
 572
 573 static int sh_dmae_runtime_suspend(struct device *dev)
 574 {
 575         return 0;
 576 }
 577
 578 static int sh_dmae_runtime_resume(struct device *dev)
 579 {
 580         struct sh_dmae_device *shdev = dev_get_drvdata(dev);
 581
 582         return sh_dmae_rst(shdev);
 583 }
 584
 585 #ifdef CONFIG_PM
 586 static int sh_dmae_suspend(struct device *dev)
 587 {
 588         return 0;
 589 }
 590
 591 static int sh_dmae_resume(struct device *dev)
 592 {
 593         struct sh_dmae_device *shdev = dev_get_drvdata(dev);
 594         int i, ret;
 595
 596         ret = sh_dmae_rst(shdev);
 597         if (ret < 0)
 598                 dev_err(dev, "Failed to reset!\n");
 599
 600         for (i = 0; i < shdev->pdata->channel_num; i++) {
 601                 struct sh_dmae_chan *sh_chan = shdev->chan[i];
 602
 603                 if (!sh_chan->shdma_chan.desc_num)
 604                         continue;
 605
 606                 if (sh_chan->shdma_chan.slave_id >= 0) {
 607                         const struct sh_dmae_slave_config *cfg = sh_chan->config;
 608                         dmae_set_dmars(sh_chan, cfg->mid_rid);
 609                         dmae_set_chcr(sh_chan, cfg->chcr);
 610                 } else {
 611                         dmae_init(sh_chan);
 612                 }
 613         }
 614
 615         return 0;
 616 }
 617 #else
 618 #define sh_dmae_suspend NULL
 619 #define sh_dmae_resume NULL
 620 #endif
 621
 622 const struct dev_pm_ops sh_dmae_pm = {
 623         .suspend                = sh_dmae_suspend,
 624         .resume                 = sh_dmae_resume,
 625         .runtime_suspend        = sh_dmae_runtime_suspend,
 626         .runtime_resume         = sh_dmae_runtime_resume,
 627 };
 628
 629 static dma_addr_t sh_dmae_slave_addr(struct shdma_chan *schan)
 630 {
 631         struct sh_dmae_chan *sh_chan = container_of(schan,
 632                                         struct sh_dmae_chan, shdma_chan);
 633
 634         /*
 635          * Implicit BUG_ON(!sh_chan->config)
 636          * This is an exclusive slave DMA operation, may only be called after a
 637          * successful slave configuration.
 638          */
 639         return sh_chan->config->addr;
 640 }
 641
 642 static struct shdma_desc *sh_dmae_embedded_desc(void *buf, int i)
 643 {
 644         return &((struct sh_dmae_desc *)buf)[i].shdma_desc;
 645 }
 646
 647 static const struct shdma_ops sh_dmae_shdma_ops = {
 648         .desc_completed = sh_dmae_desc_completed,
 649         .halt_channel = sh_dmae_halt,
 650         .channel_busy = sh_dmae_channel_busy,
 651         .slave_addr = sh_dmae_slave_addr,
 652         .desc_setup = sh_dmae_desc_setup,
 653         .set_slave = sh_dmae_set_slave,
 654         .setup_xfer = sh_dmae_setup_xfer,
 655         .start_xfer = sh_dmae_start_xfer,
 656         .embedded_desc = sh_dmae_embedded_desc,
 657         .chan_irq = sh_dmae_chan_irq,
 658         .get_partial = sh_dmae_get_partial,
 659 };
 660
 661 static int sh_dmae_probe(struct platform_device *pdev)
 662 {
 663         struct sh_dmae_pdata *pdata = pdev->dev.platform_data;
 664         unsigned long irqflags = IRQF_DISABLED,
 665                 chan_flag[SH_DMAE_MAX_CHANNELS] = {};
 666         int errirq, chan_irq[SH_DMAE_MAX_CHANNELS];
 667         int err, i, irq_cnt = 0, irqres = 0, irq_cap = 0;
 668         struct sh_dmae_device *shdev;
 669         struct dma_device *dma_dev;
 670         struct resource *chan, *dmars, *errirq_res, *chanirq_res;
 671
 672         /* get platform data */
 673         if (!pdata || !pdata->channel_num)
 674                 return -ENODEV;
 675
 676         chan = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 677         /* DMARS area is optional */
 678         dmars = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 679         /*
 680          * IRQ resources:
 681          * 1. there always must be at least one IRQ IO-resource. On SH4 it is
 682          *    the error IRQ, in which case it is the only IRQ in this resource:
 683          *    start == end. If it is the only IRQ resource, all channels also
 684          *    use the same IRQ.
 685          * 2. DMA channel IRQ resources can be specified one per resource or in
 686          *    ranges (start != end)
 687          * 3. iff all events (channels and, optionally, error) on this
 688          *    controller use the same IRQ, only one IRQ resource can be
 689          *    specified, otherwise there must be one IRQ per channel, even if
 690          *    some of them are equal
 691          * 4. if all IRQs on this controller are equal or if some specific IRQs
 692          *    specify IORESOURCE_IRQ_SHAREABLE in their resources, they will be
 693          *    requested with the IRQF_SHARED flag
 694          */
 695         errirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 696         if (!chan || !errirq_res)
 697                 return -ENODEV;
 698
 699         if (!request_mem_region(chan->start, resource_size(chan), pdev->name)) {
 700                 dev_err(&pdev->dev, "DMAC register region already claimed\n");
 701                 return -EBUSY;
 702         }
 703
 704         if (dmars && !request_mem_region(dmars->start, resource_size(dmars), pdev->name)) {
 705                 dev_err(&pdev->dev, "DMAC DMARS region already claimed\n");
 706                 err = -EBUSY;
 707                 goto ermrdmars;
 708         }
 709
 710         err = -ENOMEM;
 711         shdev = kzalloc(sizeof(struct sh_dmae_device), GFP_KERNEL);
 712         if (!shdev) {
 713                 dev_err(&pdev->dev, "Not enough memory\n");
 714                 goto ealloc;
 715         }
 716
 717         dma_dev = &shdev->shdma_dev.dma_dev;
 718
 719         shdev->chan_reg = ioremap(chan->start, resource_size(chan));
 720         if (!shdev->chan_reg)
 721                 goto emapchan;
 722         if (dmars) {
 723                 shdev->dmars = ioremap(dmars->start, resource_size(dmars));
 724                 if (!shdev->dmars)
 725                         goto emapdmars;
 726         }
 727
 728         if (!pdata->slave_only)
 729                 dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask);
 730         if (pdata->slave && pdata->slave_num)
 731                 dma_cap_set(DMA_SLAVE, dma_dev->cap_mask);
 732
 733         /* Default transfer size of 32 bytes requires 32-byte alignment */
 734         dma_dev->copy_align = LOG2_DEFAULT_XFER_SIZE;
 735
 736         shdev->shdma_dev.ops = &sh_dmae_shdma_ops;
 737         shdev->shdma_dev.desc_size = sizeof(struct sh_dmae_desc);
 738         err = shdma_init(&pdev->dev, &shdev->shdma_dev,
 739                               pdata->channel_num);
 740         if (err < 0)
 741                 goto eshdma;
 742
 743         /* platform data */
 744         shdev->pdata = pdata;
 745
 746         if (pdata->chcr_offset)
 747                 shdev->chcr_offset = pdata->chcr_offset;
 748         else
 749                 shdev->chcr_offset = CHCR;
 750
 751         if (pdata->chcr_ie_bit)
 752                 shdev->chcr_ie_bit = pdata->chcr_ie_bit;
 753         else
 754                 shdev->chcr_ie_bit = CHCR_IE;
 755
 756         platform_set_drvdata(pdev, shdev);
 757
 758         pm_runtime_enable(&pdev->dev);
 759         err = pm_runtime_get_sync(&pdev->dev);
 760         if (err < 0)
 761                 dev_err(&pdev->dev, "%s(): GET = %d\n", __func__, err);
 762
 763         spin_lock_irq(&sh_dmae_lock);
 764         list_add_tail_rcu(&shdev->node, &sh_dmae_devices);
 765         spin_unlock_irq(&sh_dmae_lock);
 766
 767         /* reset dma controller - only needed as a test */
 768         err = sh_dmae_rst(shdev);
 769         if (err)
 770                 goto rst_err;
 771
 772 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_ARCH_SHMOBILE)
 773         chanirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
 774
 775         if (!chanirq_res)
 776                 chanirq_res = errirq_res;
 777         else
 778                 irqres++;
 779
 780         if (chanirq_res == errirq_res ||
 781             (errirq_res->flags & IORESOURCE_BITS) == IORESOURCE_IRQ_SHAREABLE)
 782                 irqflags = IRQF_SHARED;
 783
 784         errirq = errirq_res->start;
 785
 786         err = request_irq(errirq, sh_dmae_err, irqflags,
 787                           "DMAC Address Error", shdev);
 788         if (err) {
 789                 dev_err(&pdev->dev,
 790                         "DMA failed requesting irq #%d, error %d\n",
 791                         errirq, err);
 792                 goto eirq_err;
 793         }
 794
 795 #else
 796         chanirq_res = errirq_res;
 797 #endif /* CONFIG_CPU_SH4 || CONFIG_ARCH_SHMOBILE */
 798
 799         if (chanirq_res->start == chanirq_res->end &&
 800             !platform_get_resource(pdev, IORESOURCE_IRQ, 1)) {
 801                 /* Special case - all multiplexed */
 802                 for (; irq_cnt < pdata->channel_num; irq_cnt++) {
 803                         if (irq_cnt < SH_DMAE_MAX_CHANNELS) {
 804                                 chan_irq[irq_cnt] = chanirq_res->start;
 805                                 chan_flag[irq_cnt] = IRQF_SHARED;
 806                         } else {
 807                                 irq_cap = 1;
 808                                 break;
 809                         }
 810                 }
 811         } else {
 812                 do {
 813                         for (i = chanirq_res->start; i <= chanirq_res->end; i++) {
 814                                 if (irq_cnt >= SH_DMAE_MAX_CHANNELS) {
 815                                         irq_cap = 1;
 816                                         break;
 817                                 }
 818
 819                                 if ((errirq_res->flags & IORESOURCE_BITS) ==
 820                                     IORESOURCE_IRQ_SHAREABLE)
 821                                         chan_flag[irq_cnt] = IRQF_SHARED;
 822                                 else
 823                                         chan_flag[irq_cnt] = IRQF_DISABLED;
 824                                 dev_dbg(&pdev->dev,
 825                                         "Found IRQ %d for channel %d\n",
 826                                         i, irq_cnt);
 827                                 chan_irq[irq_cnt++] = i;
 828                         }
 829
 830                         if (irq_cnt >= SH_DMAE_MAX_CHANNELS)
 831                                 break;
 832
 833                         chanirq_res = platform_get_resource(pdev,
 834                                                 IORESOURCE_IRQ, ++irqres);
 835                 } while (irq_cnt < pdata->channel_num && chanirq_res);
 836         }
 837
 838         /* Create DMA Channel */
 839         for (i = 0; i < irq_cnt; i++) {
 840                 err = sh_dmae_chan_probe(shdev, i, chan_irq[i], chan_flag[i]);
 841                 if (err)
 842                         goto chan_probe_err;
 843         }
 844
 845         if (irq_cap)
 846                 dev_notice(&pdev->dev, "Attempting to register %d DMA "
 847                            "channels when a maximum of %d are supported.\n",
 848                            pdata->channel_num, SH_DMAE_MAX_CHANNELS);
 849
 850         pm_runtime_put(&pdev->dev);
 851
 852         err = dma_async_device_register(&shdev->shdma_dev.dma_dev);
 853         if (err < 0)
 854                 goto edmadevreg;
 855
 856         return err;
 857
 858 edmadevreg:
 859         pm_runtime_get(&pdev->dev);
 860
 861 chan_probe_err:
 862         sh_dmae_chan_remove(shdev);
 863
 864 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_ARCH_SHMOBILE)
 865         free_irq(errirq, shdev);
 866 eirq_err:
 867 #endif
 868 rst_err:
 869         spin_lock_irq(&sh_dmae_lock);
 870         list_del_rcu(&shdev->node);
 871         spin_unlock_irq(&sh_dmae_lock);
 872
 873         pm_runtime_put(&pdev->dev);
 874         pm_runtime_disable(&pdev->dev);
 875
 876         platform_set_drvdata(pdev, NULL);
 877         shdma_cleanup(&shdev->shdma_dev);
 878 eshdma:
 879         if (dmars)
 880                 iounmap(shdev->dmars);
 881 emapdmars:
 882         iounmap(shdev->chan_reg);
 883         synchronize_rcu();
 884 emapchan:
 885         kfree(shdev);
 886 ealloc:
 887         if (dmars)
 888                 release_mem_region(dmars->start, resource_size(dmars));
 889 ermrdmars:
 890         release_mem_region(chan->start, resource_size(chan));
 891
 892         return err;
 893 }
 894
 895 static int sh_dmae_remove(struct platform_device *pdev)
 896 {
 897         struct sh_dmae_device *shdev = platform_get_drvdata(pdev);
 898         struct dma_device *dma_dev = &shdev->shdma_dev.dma_dev;
 899         struct resource *res;
 900         int errirq = platform_get_irq(pdev, 0);
 901
 902         dma_async_device_unregister(dma_dev);
 903
 904         if (errirq > 0)
 905                 free_irq(errirq, shdev);
 906
 907         spin_lock_irq(&sh_dmae_lock);
 908         list_del_rcu(&shdev->node);
 909         spin_unlock_irq(&sh_dmae_lock);
 910
 911         pm_runtime_disable(&pdev->dev);
 912
 913         sh_dmae_chan_remove(shdev);
 914         shdma_cleanup(&shdev->shdma_dev);
 915
 916         if (shdev->dmars)
 917                 iounmap(shdev->dmars);
 918         iounmap(shdev->chan_reg);
 919
 920         platform_set_drvdata(pdev, NULL);
 921
 922         synchronize_rcu();
 923         kfree(shdev);
 924
 925         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 926         if (res)
 927                 release_mem_region(res->start, resource_size(res));
 928         res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 929         if (res)
 930                 release_mem_region(res->start, resource_size(res));
 931
 932         return 0;
 933 }
 934
 935 static const struct of_device_id sh_dmae_of_match[] = {
 936         { .compatible = "renesas,shdma", },
 937         { }
 938 };
 939 MODULE_DEVICE_TABLE(of, sh_dmae_of_match);
 940
 941 static struct platform_driver sh_dmae_driver = {
 942         .driver         = {
 943                 .owner  = THIS_MODULE,
 944                 .pm     = &sh_dmae_pm,
 945                 .name   = SH_DMAE_DRV_NAME,
 946                 .of_match_table = sh_dmae_of_match,
 947         },
 948         .remove         = sh_dmae_remove,
 949         .shutdown       = sh_dmae_shutdown,
 950 };
 951
 952 static int __init sh_dmae_init(void)
 953 {
 954         /* Wire up NMI handling */
 955         int err = register_die_notifier(&sh_dmae_nmi_notifier);
 956         if (err)
 957                 return err;
 958
 959         return platform_driver_probe(&sh_dmae_driver, sh_dmae_probe);
 960 }
 961 module_init(sh_dmae_init);
 962
 963 static void __exit sh_dmae_exit(void)
 964 {
 965         platform_driver_unregister(&sh_dmae_driver);
 966
 967         unregister_die_notifier(&sh_dmae_nmi_notifier);
 968 }
 969 module_exit(sh_dmae_exit);
 970
 971 MODULE_AUTHOR("Nobuhiro Iwamatsu <[email protected]>");
 972 MODULE_DESCRIPTION("Renesas SH DMA Engine driver");
 973 MODULE_LICENSE("GPL");
 974 MODULE_ALIAS("platform:" SH_DMAE_DRV_NAME);