drivers/dma/sh/shdmac.c

   1 /*
   2  * Renesas SuperH DMA Engine support
   3  *
   4  * base is drivers/dma/flsdma.c
   5  *
   6  * Copyright (C) 2011-2012 Guennadi Liakhovetski <g.liakhovetski@gmx.de>
   7  * Copyright (C) 2009 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
   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/of.h>
  24 #include <linux/of_device.h>
  25 #include <linux/slab.h>
  26 #include <linux/interrupt.h>
  27 #include <linux/dmaengine.h>
  28 #include <linux/delay.h>
  29 #include <linux/platform_device.h>
  30 #include <linux/pm_runtime.h>
  31 #include <linux/sh_dma.h>
  32 #include <linux/notifier.h>
  33 #include <linux/kdebug.h>
  34 #include <linux/spinlock.h>
  35 #include <linux/rculist.h>
  36
  37 #include "../dmaengine.h"
  38 #include "shdma.h"
  39
  40 /* DMA register */
  41 #define SAR     0x00
  42 #define DAR     0x04
  43 #define TCR     0x08
  44 #define CHCR    0x0C
  45 #define DMAOR   0x40
  46
  47 #define TEND    0x18 /* USB-DMAC */
  48
  49 #define SH_DMAE_DRV_NAME "sh-dma-engine"
  50
  51 /* Default MEMCPY transfer size = 2^2 = 4 bytes */
  52 #define LOG2_DEFAULT_XFER_SIZE  2
  53 #define SH_DMA_SLAVE_NUMBER 256
  54 #define SH_DMA_TCR_MAX (16 * 1024 * 1024 - 1)
  55
  56 /*
  57  * Used for write-side mutual exclusion for the global device list,
  58  * read-side synchronization by way of RCU, and per-controller data.
  59  */
  60 static DEFINE_SPINLOCK(sh_dmae_lock);
  61 static LIST_HEAD(sh_dmae_devices);
  62
  63 /*
  64  * Different DMAC implementations provide different ways to clear DMA channels:
  65  * (1) none - no CHCLR registers are available
  66  * (2) one CHCLR register per channel - 0 has to be written to it to clear
  67  *     channel buffers
  68  * (3) one CHCLR per several channels - 1 has to be written to the bit,
  69  *     corresponding to the specific channel to reset it
  70  */
  71 static void channel_clear(struct sh_dmae_chan *sh_dc)
  72 {
  73         struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
  74         const struct sh_dmae_channel *chan_pdata = shdev->pdata->channel +
  75                 sh_dc->shdma_chan.id;
  76         u32 val = shdev->pdata->chclr_bitwise ? 1 << chan_pdata->chclr_bit : 0;
  77
  78         __raw_writel(val, shdev->chan_reg + chan_pdata->chclr_offset);
  79 }
  80
  81 static void sh_dmae_writel(struct sh_dmae_chan *sh_dc, u32 data, u32 reg)
  82 {
  83         __raw_writel(data, sh_dc->base + reg);
  84 }
  85
  86 static u32 sh_dmae_readl(struct sh_dmae_chan *sh_dc, u32 reg)
  87 {
  88         return __raw_readl(sh_dc->base + reg);
  89 }
  90
  91 static u16 dmaor_read(struct sh_dmae_device *shdev)
  92 {
  93         void __iomem *addr = shdev->chan_reg + DMAOR;
  94
  95         if (shdev->pdata->dmaor_is_32bit)
  96                 return __raw_readl(addr);
  97         else
  98                 return __raw_readw(addr);
  99 }
 100
 101 static void dmaor_write(struct sh_dmae_device *shdev, u16 data)
 102 {
 103         void __iomem *addr = shdev->chan_reg + DMAOR;
 104
 105         if (shdev->pdata->dmaor_is_32bit)
 106                 __raw_writel(data, addr);
 107         else
 108                 __raw_writew(data, addr);
 109 }
 110
 111 static void chcr_write(struct sh_dmae_chan *sh_dc, u32 data)
 112 {
 113         struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
 114
 115         __raw_writel(data, sh_dc->base + shdev->chcr_offset);
 116 }
 117
 118 static u32 chcr_read(struct sh_dmae_chan *sh_dc)
 119 {
 120         struct sh_dmae_device *shdev = to_sh_dev(sh_dc);
 121
 122         return __raw_readl(sh_dc->base + shdev->chcr_offset);
 123 }
 124
 125 /*
 126  * Reset DMA controller
 127  *
 128  * SH7780 has two DMAOR register
 129  */
 130 static void sh_dmae_ctl_stop(struct sh_dmae_device *shdev)
 131 {
 132         unsigned short dmaor;
 133         unsigned long flags;
 134
 135         spin_lock_irqsave(&sh_dmae_lock, flags);
 136
 137         dmaor = dmaor_read(shdev);
 138         dmaor_write(shdev, dmaor & ~(DMAOR_NMIF | DMAOR_AE | DMAOR_DME));
 139
 140         spin_unlock_irqrestore(&sh_dmae_lock, flags);
 141 }
 142
 143 static int sh_dmae_rst(struct sh_dmae_device *shdev)
 144 {
 145         unsigned short dmaor;
 146         unsigned long flags;
 147
 148         spin_lock_irqsave(&sh_dmae_lock, flags);
 149
 150         dmaor = dmaor_read(shdev) & ~(DMAOR_NMIF | DMAOR_AE | DMAOR_DME);
 151
 152         if (shdev->pdata->chclr_present) {
 153                 int i;
 154                 for (i = 0; i < shdev->pdata->channel_num; i++) {
 155                         struct sh_dmae_chan *sh_chan = shdev->chan[i];
 156                         if (sh_chan)
 157                                 channel_clear(sh_chan);
 158                 }
 159         }
 160
 161         dmaor_write(shdev, dmaor | shdev->pdata->dmaor_init);
 162
 163         dmaor = dmaor_read(shdev);
 164
 165         spin_unlock_irqrestore(&sh_dmae_lock, flags);
 166
 167         if (dmaor & (DMAOR_AE | DMAOR_NMIF)) {
 168                 dev_warn(shdev->shdma_dev.dma_dev.dev, "Can't initialize DMAOR.\n");
 169                 return -EIO;
 170         }
 171         if (shdev->pdata->dmaor_init & ~dmaor)
 172                 dev_warn(shdev->shdma_dev.dma_dev.dev,
 173                          "DMAOR=0x%x hasn't latched the initial value 0x%x.\n",
 174                          dmaor, shdev->pdata->dmaor_init);
 175         return 0;
 176 }
 177
 178 static bool dmae_is_busy(struct sh_dmae_chan *sh_chan)
 179 {
 180         u32 chcr = chcr_read(sh_chan);
 181
 182         if ((chcr & (CHCR_DE | CHCR_TE)) == CHCR_DE)
 183                 return true; /* working */
 184
 185         return false; /* waiting */
 186 }
 187
 188 static unsigned int calc_xmit_shift(struct sh_dmae_chan *sh_chan, u32 chcr)
 189 {
 190         struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
 191         const struct sh_dmae_pdata *pdata = shdev->pdata;
 192         int cnt = ((chcr & pdata->ts_low_mask) >> pdata->ts_low_shift) |
 193                 ((chcr & pdata->ts_high_mask) >> pdata->ts_high_shift);
 194
 195         if (cnt >= pdata->ts_shift_num)
 196                 cnt = 0;
 197
 198         return pdata->ts_shift[cnt];
 199 }
 200
 201 static u32 log2size_to_chcr(struct sh_dmae_chan *sh_chan, int l2size)
 202 {
 203         struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
 204         const struct sh_dmae_pdata *pdata = shdev->pdata;
 205         int i;
 206
 207         for (i = 0; i < pdata->ts_shift_num; i++)
 208                 if (pdata->ts_shift[i] == l2size)
 209                         break;
 210
 211         if (i == pdata->ts_shift_num)
 212                 i = 0;
 213
 214         return ((i << pdata->ts_low_shift) & pdata->ts_low_mask) |
 215                 ((i << pdata->ts_high_shift) & pdata->ts_high_mask);
 216 }
 217
 218 static void dmae_set_reg(struct sh_dmae_chan *sh_chan, struct sh_dmae_regs *hw)
 219 {
 220         sh_dmae_writel(sh_chan, hw->sar, SAR);
 221         sh_dmae_writel(sh_chan, hw->dar, DAR);
 222         sh_dmae_writel(sh_chan, hw->tcr >> sh_chan->xmit_shift, TCR);
 223 }
 224
 225 static void dmae_start(struct sh_dmae_chan *sh_chan)
 226 {
 227         struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
 228         u32 chcr = chcr_read(sh_chan);
 229
 230         if (shdev->pdata->needs_tend_set)
 231                 sh_dmae_writel(sh_chan, 0xFFFFFFFF, TEND);
 232
 233         chcr |= CHCR_DE | shdev->chcr_ie_bit;
 234         chcr_write(sh_chan, chcr & ~CHCR_TE);
 235 }
 236
 237 static void dmae_init(struct sh_dmae_chan *sh_chan)
 238 {
 239         /*
 240          * Default configuration for dual address memory-memory transfer.
 241          * 0x400 represents auto-request.
 242          */
 243         u32 chcr = DM_INC | SM_INC | 0x400 | log2size_to_chcr(sh_chan,
 244                                                    LOG2_DEFAULT_XFER_SIZE);
 245         sh_chan->xmit_shift = calc_xmit_shift(sh_chan, chcr);
 246         chcr_write(sh_chan, chcr);
 247 }
 248
 249 static int dmae_set_chcr(struct sh_dmae_chan *sh_chan, u32 val)
 250 {
 251         /* If DMA is active, cannot set CHCR. TODO: remove this superfluous check */
 252         if (dmae_is_busy(sh_chan))
 253                 return -EBUSY;
 254
 255         sh_chan->xmit_shift = calc_xmit_shift(sh_chan, val);
 256         chcr_write(sh_chan, val);
 257
 258         return 0;
 259 }
 260
 261 static int dmae_set_dmars(struct sh_dmae_chan *sh_chan, u16 val)
 262 {
 263         struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
 264         const struct sh_dmae_pdata *pdata = shdev->pdata;
 265         const struct sh_dmae_channel *chan_pdata = &pdata->channel[sh_chan->shdma_chan.id];
 266         void __iomem *addr = shdev->dmars;
 267         unsigned int shift = chan_pdata->dmars_bit;
 268
 269         if (dmae_is_busy(sh_chan))
 270                 return -EBUSY;
 271
 272         if (pdata->no_dmars)
 273                 return 0;
 274
 275         /* in the case of a missing DMARS resource use first memory window */
 276         if (!addr)
 277                 addr = shdev->chan_reg;
 278         addr += chan_pdata->dmars;
 279
 280         __raw_writew((__raw_readw(addr) & (0xff00 >> shift)) | (val << shift),
 281                      addr);
 282
 283         return 0;
 284 }
 285
 286 static void sh_dmae_start_xfer(struct shdma_chan *schan,
 287                                struct shdma_desc *sdesc)
 288 {
 289         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
 290                                                     shdma_chan);
 291         struct sh_dmae_desc *sh_desc = container_of(sdesc,
 292                                         struct sh_dmae_desc, shdma_desc);
 293         dev_dbg(sh_chan->shdma_chan.dev, "Queue #%d to %d: %u@%x -> %x\n",
 294                 sdesc->async_tx.cookie, sh_chan->shdma_chan.id,
 295                 sh_desc->hw.tcr, sh_desc->hw.sar, sh_desc->hw.dar);
 296         /* Get the ld start address from ld_queue */
 297         dmae_set_reg(sh_chan, &sh_desc->hw);
 298         dmae_start(sh_chan);
 299 }
 300
 301 static bool sh_dmae_channel_busy(struct shdma_chan *schan)
 302 {
 303         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
 304                                                     shdma_chan);
 305         return dmae_is_busy(sh_chan);
 306 }
 307
 308 static void sh_dmae_setup_xfer(struct shdma_chan *schan,
 309                                int slave_id)
 310 {
 311         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
 312                                                     shdma_chan);
 313
 314         if (slave_id >= 0) {
 315                 const struct sh_dmae_slave_config *cfg =
 316                         sh_chan->config;
 317
 318                 dmae_set_dmars(sh_chan, cfg->mid_rid);
 319                 dmae_set_chcr(sh_chan, cfg->chcr);
 320         } else {
 321                 dmae_init(sh_chan);
 322         }
 323 }
 324
 325 /*
 326  * Find a slave channel configuration from the contoller list by either a slave
 327  * ID in the non-DT case, or by a MID/RID value in the DT case
 328  */
 329 static const struct sh_dmae_slave_config *dmae_find_slave(
 330         struct sh_dmae_chan *sh_chan, int match)
 331 {
 332         struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
 333         const struct sh_dmae_pdata *pdata = shdev->pdata;
 334         const struct sh_dmae_slave_config *cfg;
 335         int i;
 336
 337         if (!sh_chan->shdma_chan.dev->of_node) {
 338                 if (match >= SH_DMA_SLAVE_NUMBER)
 339                         return NULL;
 340
 341                 for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++)
 342                         if (cfg->slave_id == match)
 343                                 return cfg;
 344         } else {
 345                 for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++)
 346                         if (cfg->mid_rid == match) {
 347                                 sh_chan->shdma_chan.slave_id = i;
 348                                 return cfg;
 349                         }
 350         }
 351
 352         return NULL;
 353 }
 354
 355 static int sh_dmae_set_slave(struct shdma_chan *schan,
 356                              int slave_id, dma_addr_t slave_addr, bool try)
 357 {
 358         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
 359                                                     shdma_chan);
 360         const struct sh_dmae_slave_config *cfg = dmae_find_slave(sh_chan, slave_id);
 361         if (!cfg)
 362                 return -ENXIO;
 363
 364         if (!try) {
 365                 sh_chan->config = cfg;
 366                 sh_chan->slave_addr = slave_addr ? : cfg->addr;
 367         }
 368
 369         return 0;
 370 }
 371
 372 static void dmae_halt(struct sh_dmae_chan *sh_chan)
 373 {
 374         struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
 375         u32 chcr = chcr_read(sh_chan);
 376
 377         chcr &= ~(CHCR_DE | CHCR_TE | shdev->chcr_ie_bit);
 378         chcr_write(sh_chan, chcr);
 379 }
 380
 381 static int sh_dmae_desc_setup(struct shdma_chan *schan,
 382                               struct shdma_desc *sdesc,
 383                               dma_addr_t src, dma_addr_t dst, size_t *len)
 384 {
 385         struct sh_dmae_desc *sh_desc = container_of(sdesc,
 386                                         struct sh_dmae_desc, shdma_desc);
 387
 388         if (*len > schan->max_xfer_len)
 389                 *len = schan->max_xfer_len;
 390
 391         sh_desc->hw.sar = src;
 392         sh_desc->hw.dar = dst;
 393         sh_desc->hw.tcr = *len;
 394
 395         return 0;
 396 }
 397
 398 static void sh_dmae_halt(struct shdma_chan *schan)
 399 {
 400         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
 401                                                     shdma_chan);
 402         dmae_halt(sh_chan);
 403 }
 404
 405 static bool sh_dmae_chan_irq(struct shdma_chan *schan, int irq)
 406 {
 407         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
 408                                                     shdma_chan);
 409
 410         if (!(chcr_read(sh_chan) & CHCR_TE))
 411                 return false;
 412
 413         /* DMA stop */
 414         dmae_halt(sh_chan);
 415
 416         return true;
 417 }
 418
 419 static size_t sh_dmae_get_partial(struct shdma_chan *schan,
 420                                   struct shdma_desc *sdesc)
 421 {
 422         struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan,
 423                                                     shdma_chan);
 424         struct sh_dmae_desc *sh_desc = container_of(sdesc,
 425                                         struct sh_dmae_desc, shdma_desc);
 426         return sh_desc->hw.tcr -
 427                 (sh_dmae_readl(sh_chan, TCR) << sh_chan->xmit_shift);
 428 }
 429
 430 /* Called from error IRQ or NMI */
 431 static bool sh_dmae_reset(struct sh_dmae_device *shdev)
 432 {
 433         bool ret;
 434
 435         /* halt the dma controller */
 436         sh_dmae_ctl_stop(shdev);
 437
 438         /* We cannot detect, which channel caused the error, have to reset all */
 439         ret = shdma_reset(&shdev->shdma_dev);
 440
 441         sh_dmae_rst(shdev);
 442
 443         return ret;
 444 }
 445
 446 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_ARM)
 447 static irqreturn_t sh_dmae_err(int irq, void *data)
 448 {
 449         struct sh_dmae_device *shdev = data;
 450
 451         if (!(dmaor_read(shdev) & DMAOR_AE))
 452                 return IRQ_NONE;
 453
 454         sh_dmae_reset(shdev);
 455         return IRQ_HANDLED;
 456 }
 457 #endif
 458
 459 static bool sh_dmae_desc_completed(struct shdma_chan *schan,
 460                                    struct shdma_desc *sdesc)
 461 {
 462         struct sh_dmae_chan *sh_chan = container_of(schan,
 463                                         struct sh_dmae_chan, shdma_chan);
 464         struct sh_dmae_desc *sh_desc = container_of(sdesc,
 465                                         struct sh_dmae_desc, shdma_desc);
 466         u32 sar_buf = sh_dmae_readl(sh_chan, SAR);
 467         u32 dar_buf = sh_dmae_readl(sh_chan, DAR);
 468
 469         return  (sdesc->direction == DMA_DEV_TO_MEM &&
 470                  (sh_desc->hw.dar + sh_desc->hw.tcr) == dar_buf) ||
 471                 (sdesc->direction != DMA_DEV_TO_MEM &&
 472                  (sh_desc->hw.sar + sh_desc->hw.tcr) == sar_buf);
 473 }
 474
 475 static bool sh_dmae_nmi_notify(struct sh_dmae_device *shdev)
 476 {
 477         /* Fast path out if NMIF is not asserted for this controller */
 478         if ((dmaor_read(shdev) & DMAOR_NMIF) == 0)
 479                 return false;
 480
 481         return sh_dmae_reset(shdev);
 482 }
 483
 484 static int sh_dmae_nmi_handler(struct notifier_block *self,
 485                                unsigned long cmd, void *data)
 486 {
 487         struct sh_dmae_device *shdev;
 488         int ret = NOTIFY_DONE;
 489         bool triggered;
 490
 491         /*
 492          * Only concern ourselves with NMI events.
 493          *
 494          * Normally we would check the die chain value, but as this needs
 495          * to be architecture independent, check for NMI context instead.
 496          */
 497         if (!in_nmi())
 498                 return NOTIFY_DONE;
 499
 500         rcu_read_lock();
 501         list_for_each_entry_rcu(shdev, &sh_dmae_devices, node) {
 502                 /*
 503                  * Only stop if one of the controllers has NMIF asserted,
 504                  * we do not want to interfere with regular address error
 505                  * handling or NMI events that don't concern the DMACs.
 506                  */
 507                 triggered = sh_dmae_nmi_notify(shdev);
 508                 if (triggered == true)
 509                         ret = NOTIFY_OK;
 510         }
 511         rcu_read_unlock();
 512
 513         return ret;
 514 }
 515
 516 static struct notifier_block sh_dmae_nmi_notifier __read_mostly = {
 517         .notifier_call  = sh_dmae_nmi_handler,
 518
 519         /* Run before NMI debug handler and KGDB */
 520         .priority       = 1,
 521 };
 522
 523 static int sh_dmae_chan_probe(struct sh_dmae_device *shdev, int id,
 524                                         int irq, unsigned long flags)
 525 {
 526         const struct sh_dmae_channel *chan_pdata = &shdev->pdata->channel[id];
 527         struct shdma_dev *sdev = &shdev->shdma_dev;
 528         struct platform_device *pdev = to_platform_device(sdev->dma_dev.dev);
 529         struct sh_dmae_chan *sh_chan;
 530         struct shdma_chan *schan;
 531         int err;
 532
 533         sh_chan = devm_kzalloc(sdev->dma_dev.dev, sizeof(struct sh_dmae_chan),
 534                                GFP_KERNEL);
 535         if (!sh_chan) {
 536                 dev_err(sdev->dma_dev.dev,
 537                         "No free memory for allocating dma channels!\n");
 538                 return -ENOMEM;
 539         }
 540
 541         schan = &sh_chan->shdma_chan;
 542         schan->max_xfer_len = SH_DMA_TCR_MAX + 1;
 543
 544         shdma_chan_probe(sdev, schan, id);
 545
 546         sh_chan->base = shdev->chan_reg + chan_pdata->offset;
 547
 548         /* set up channel irq */
 549         if (pdev->id >= 0)
 550                 snprintf(sh_chan->dev_id, sizeof(sh_chan->dev_id),
 551                          "sh-dmae%d.%d", pdev->id, id);
 552         else
 553                 snprintf(sh_chan->dev_id, sizeof(sh_chan->dev_id),
 554                          "sh-dma%d", id);
 555
 556         err = shdma_request_irq(schan, irq, flags, sh_chan->dev_id);
 557         if (err) {
 558                 dev_err(sdev->dma_dev.dev,
 559                         "DMA channel %d request_irq error %d\n",
 560                         id, err);
 561                 goto err_no_irq;
 562         }
 563
 564         shdev->chan[id] = sh_chan;
 565         return 0;
 566
 567 err_no_irq:
 568         /* remove from dmaengine device node */
 569         shdma_chan_remove(schan);
 570         return err;
 571 }
 572
 573 static void sh_dmae_chan_remove(struct sh_dmae_device *shdev)
 574 {
 575         struct dma_device *dma_dev = &shdev->shdma_dev.dma_dev;
 576         struct shdma_chan *schan;
 577         int i;
 578
 579         shdma_for_each_chan(schan, &shdev->shdma_dev, i) {
 580                 BUG_ON(!schan);
 581
 582                 shdma_chan_remove(schan);
 583         }
 584         dma_dev->chancnt = 0;
 585 }
 586
 587 static void sh_dmae_shutdown(struct platform_device *pdev)
 588 {
 589         struct sh_dmae_device *shdev = platform_get_drvdata(pdev);
 590         sh_dmae_ctl_stop(shdev);
 591 }
 592
 593 static int sh_dmae_runtime_suspend(struct device *dev)
 594 {
 595         return 0;
 596 }
 597
 598 static int sh_dmae_runtime_resume(struct device *dev)
 599 {
 600         struct sh_dmae_device *shdev = dev_get_drvdata(dev);
 601
 602         return sh_dmae_rst(shdev);
 603 }
 604
 605 #ifdef CONFIG_PM
 606 static int sh_dmae_suspend(struct device *dev)
 607 {
 608         return 0;
 609 }
 610
 611 static int sh_dmae_resume(struct device *dev)
 612 {
 613         struct sh_dmae_device *shdev = dev_get_drvdata(dev);
 614         int i, ret;
 615
 616         ret = sh_dmae_rst(shdev);
 617         if (ret < 0)
 618                 dev_err(dev, "Failed to reset!\n");
 619
 620         for (i = 0; i < shdev->pdata->channel_num; i++) {
 621                 struct sh_dmae_chan *sh_chan = shdev->chan[i];
 622
 623                 if (!sh_chan->shdma_chan.desc_num)
 624                         continue;
 625
 626                 if (sh_chan->shdma_chan.slave_id >= 0) {
 627                         const struct sh_dmae_slave_config *cfg = sh_chan->config;
 628                         dmae_set_dmars(sh_chan, cfg->mid_rid);
 629                         dmae_set_chcr(sh_chan, cfg->chcr);
 630                 } else {
 631                         dmae_init(sh_chan);
 632                 }
 633         }
 634
 635         return 0;
 636 }
 637 #else
 638 #define sh_dmae_suspend NULL
 639 #define sh_dmae_resume NULL
 640 #endif
 641
 642 static const struct dev_pm_ops sh_dmae_pm = {
 643         .suspend                = sh_dmae_suspend,
 644         .resume                 = sh_dmae_resume,
 645         .runtime_suspend        = sh_dmae_runtime_suspend,
 646         .runtime_resume         = sh_dmae_runtime_resume,
 647 };
 648
 649 static dma_addr_t sh_dmae_slave_addr(struct shdma_chan *schan)
 650 {
 651         struct sh_dmae_chan *sh_chan = container_of(schan,
 652                                         struct sh_dmae_chan, shdma_chan);
 653
 654         /*
 655          * Implicit BUG_ON(!sh_chan->config)
 656          * This is an exclusive slave DMA operation, may only be called after a
 657          * successful slave configuration.
 658          */
 659         return sh_chan->slave_addr;
 660 }
 661
 662 static struct shdma_desc *sh_dmae_embedded_desc(void *buf, int i)
 663 {
 664         return &((struct sh_dmae_desc *)buf)[i].shdma_desc;
 665 }
 666
 667 static const struct shdma_ops sh_dmae_shdma_ops = {
 668         .desc_completed = sh_dmae_desc_completed,
 669         .halt_channel = sh_dmae_halt,
 670         .channel_busy = sh_dmae_channel_busy,
 671         .slave_addr = sh_dmae_slave_addr,
 672         .desc_setup = sh_dmae_desc_setup,
 673         .set_slave = sh_dmae_set_slave,
 674         .setup_xfer = sh_dmae_setup_xfer,
 675         .start_xfer = sh_dmae_start_xfer,
 676         .embedded_desc = sh_dmae_embedded_desc,
 677         .chan_irq = sh_dmae_chan_irq,
 678         .get_partial = sh_dmae_get_partial,
 679 };
 680
 681 static const struct of_device_id sh_dmae_of_match[] = {
 682         {.compatible = "renesas,shdma-r8a73a4", .data = r8a73a4_shdma_devid,},
 683         {}
 684 };
 685 MODULE_DEVICE_TABLE(of, sh_dmae_of_match);
 686
 687 static int sh_dmae_probe(struct platform_device *pdev)
 688 {
 689         const struct sh_dmae_pdata *pdata;
 690         unsigned long chan_flag[SH_DMAE_MAX_CHANNELS] = {};
 691         int chan_irq[SH_DMAE_MAX_CHANNELS];
 692 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_ARM)
 693         unsigned long irqflags = 0;
 694         int errirq;
 695 #endif
 696         int err, i, irq_cnt = 0, irqres = 0, irq_cap = 0;
 697         struct sh_dmae_device *shdev;
 698         struct dma_device *dma_dev;
 699         struct resource *chan, *dmars, *errirq_res, *chanirq_res;
 700
 701         if (pdev->dev.of_node)
 702                 pdata = of_match_device(sh_dmae_of_match, &pdev->dev)->data;
 703         else
 704                 pdata = dev_get_platdata(&pdev->dev);
 705
 706         /* get platform data */
 707         if (!pdata || !pdata->channel_num)
 708                 return -ENODEV;
 709
 710         chan = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 711         /* DMARS area is optional */
 712         dmars = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 713         /*
 714          * IRQ resources:
 715          * 1. there always must be at least one IRQ IO-resource. On SH4 it is
 716          *    the error IRQ, in which case it is the only IRQ in this resource:
 717          *    start == end. If it is the only IRQ resource, all channels also
 718          *    use the same IRQ.
 719          * 2. DMA channel IRQ resources can be specified one per resource or in
 720          *    ranges (start != end)
 721          * 3. iff all events (channels and, optionally, error) on this
 722          *    controller use the same IRQ, only one IRQ resource can be
 723          *    specified, otherwise there must be one IRQ per channel, even if
 724          *    some of them are equal
 725          * 4. if all IRQs on this controller are equal or if some specific IRQs
 726          *    specify IORESOURCE_IRQ_SHAREABLE in their resources, they will be
 727          *    requested with the IRQF_SHARED flag
 728          */
 729         errirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 730         if (!chan || !errirq_res)
 731                 return -ENODEV;
 732
 733         shdev = devm_kzalloc(&pdev->dev, sizeof(struct sh_dmae_device),
 734                              GFP_KERNEL);
 735         if (!shdev) {
 736                 dev_err(&pdev->dev, "Not enough memory\n");
 737                 return -ENOMEM;
 738         }
 739
 740         dma_dev = &shdev->shdma_dev.dma_dev;
 741
 742         shdev->chan_reg = devm_ioremap_resource(&pdev->dev, chan);
 743         if (IS_ERR(shdev->chan_reg))
 744                 return PTR_ERR(shdev->chan_reg);
 745         if (dmars) {
 746                 shdev->dmars = devm_ioremap_resource(&pdev->dev, dmars);
 747                 if (IS_ERR(shdev->dmars))
 748                         return PTR_ERR(shdev->dmars);
 749         }
 750
 751         if (!pdata->slave_only)
 752                 dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask);
 753         if (pdata->slave && pdata->slave_num)
 754                 dma_cap_set(DMA_SLAVE, dma_dev->cap_mask);
 755
 756         /* Default transfer size of 32 bytes requires 32-byte alignment */
 757         dma_dev->copy_align = LOG2_DEFAULT_XFER_SIZE;
 758
 759         shdev->shdma_dev.ops = &sh_dmae_shdma_ops;
 760         shdev->shdma_dev.desc_size = sizeof(struct sh_dmae_desc);
 761         err = shdma_init(&pdev->dev, &shdev->shdma_dev,
 762                               pdata->channel_num);
 763         if (err < 0)
 764                 goto eshdma;
 765
 766         /* platform data */
 767         shdev->pdata = pdata;
 768
 769         if (pdata->chcr_offset)
 770                 shdev->chcr_offset = pdata->chcr_offset;
 771         else
 772                 shdev->chcr_offset = CHCR;
 773
 774         if (pdata->chcr_ie_bit)
 775                 shdev->chcr_ie_bit = pdata->chcr_ie_bit;
 776         else
 777                 shdev->chcr_ie_bit = CHCR_IE;
 778
 779         platform_set_drvdata(pdev, shdev);
 780
 781         pm_runtime_enable(&pdev->dev);
 782         err = pm_runtime_get_sync(&pdev->dev);
 783         if (err < 0)
 784                 dev_err(&pdev->dev, "%s(): GET = %d\n", __func__, err);
 785
 786         spin_lock_irq(&sh_dmae_lock);
 787         list_add_tail_rcu(&shdev->node, &sh_dmae_devices);
 788         spin_unlock_irq(&sh_dmae_lock);
 789
 790         /* reset dma controller - only needed as a test */
 791         err = sh_dmae_rst(shdev);
 792         if (err)
 793                 goto rst_err;
 794
 795 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_ARCH_SHMOBILE)
 796         chanirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
 797
 798         if (!chanirq_res)
 799                 chanirq_res = errirq_res;
 800         else
 801                 irqres++;
 802
 803         if (chanirq_res == errirq_res ||
 804             (errirq_res->flags & IORESOURCE_BITS) == IORESOURCE_IRQ_SHAREABLE)
 805                 irqflags = IRQF_SHARED;
 806
 807         errirq = errirq_res->start;
 808
 809         err = devm_request_irq(&pdev->dev, errirq, sh_dmae_err, irqflags,
 810                                "DMAC Address Error", shdev);
 811         if (err) {
 812                 dev_err(&pdev->dev,
 813                         "DMA failed requesting irq #%d, error %d\n",
 814                         errirq, err);
 815                 goto eirq_err;
 816         }
 817
 818 #else
 819         chanirq_res = errirq_res;
 820 #endif /* CONFIG_CPU_SH4 || CONFIG_ARCH_SHMOBILE */
 821
 822         if (chanirq_res->start == chanirq_res->end &&
 823             !platform_get_resource(pdev, IORESOURCE_IRQ, 1)) {
 824                 /* Special case - all multiplexed */
 825                 for (; irq_cnt < pdata->channel_num; irq_cnt++) {
 826                         if (irq_cnt < SH_DMAE_MAX_CHANNELS) {
 827                                 chan_irq[irq_cnt] = chanirq_res->start;
 828                                 chan_flag[irq_cnt] = IRQF_SHARED;
 829                         } else {
 830                                 irq_cap = 1;
 831                                 break;
 832                         }
 833                 }
 834         } else {
 835                 do {
 836                         for (i = chanirq_res->start; i <= chanirq_res->end; i++) {
 837                                 if (irq_cnt >= SH_DMAE_MAX_CHANNELS) {
 838                                         irq_cap = 1;
 839                                         break;
 840                                 }
 841
 842                                 if ((errirq_res->flags & IORESOURCE_BITS) ==
 843                                     IORESOURCE_IRQ_SHAREABLE)
 844                                         chan_flag[irq_cnt] = IRQF_SHARED;
 845                                 else
 846                                         chan_flag[irq_cnt] = 0;
 847                                 dev_dbg(&pdev->dev,
 848                                         "Found IRQ %d for channel %d\n",
 849                                         i, irq_cnt);
 850                                 chan_irq[irq_cnt++] = i;
 851                         }
 852
 853                         if (irq_cnt >= SH_DMAE_MAX_CHANNELS)
 854                                 break;
 855
 856                         chanirq_res = platform_get_resource(pdev,
 857                                                 IORESOURCE_IRQ, ++irqres);
 858                 } while (irq_cnt < pdata->channel_num && chanirq_res);
 859         }
 860
 861         /* Create DMA Channel */
 862         for (i = 0; i < irq_cnt; i++) {
 863                 err = sh_dmae_chan_probe(shdev, i, chan_irq[i], chan_flag[i]);
 864                 if (err)
 865                         goto chan_probe_err;
 866         }
 867
 868         if (irq_cap)
 869                 dev_notice(&pdev->dev, "Attempting to register %d DMA "
 870                            "channels when a maximum of %d are supported.\n",
 871                            pdata->channel_num, SH_DMAE_MAX_CHANNELS);
 872
 873         pm_runtime_put(&pdev->dev);
 874
 875         err = dma_async_device_register(&shdev->shdma_dev.dma_dev);
 876         if (err < 0)
 877                 goto edmadevreg;
 878
 879         return err;
 880
 881 edmadevreg:
 882         pm_runtime_get(&pdev->dev);
 883
 884 chan_probe_err:
 885         sh_dmae_chan_remove(shdev);
 886
 887 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_ARCH_SHMOBILE)
 888 eirq_err:
 889 #endif
 890 rst_err:
 891         spin_lock_irq(&sh_dmae_lock);
 892         list_del_rcu(&shdev->node);
 893         spin_unlock_irq(&sh_dmae_lock);
 894
 895         pm_runtime_put(&pdev->dev);
 896         pm_runtime_disable(&pdev->dev);
 897
 898         shdma_cleanup(&shdev->shdma_dev);
 899 eshdma:
 900         synchronize_rcu();
 901
 902         return err;
 903 }
 904
 905 static int sh_dmae_remove(struct platform_device *pdev)
 906 {
 907         struct sh_dmae_device *shdev = platform_get_drvdata(pdev);
 908         struct dma_device *dma_dev = &shdev->shdma_dev.dma_dev;
 909
 910         dma_async_device_unregister(dma_dev);
 911
 912         spin_lock_irq(&sh_dmae_lock);
 913         list_del_rcu(&shdev->node);
 914         spin_unlock_irq(&sh_dmae_lock);
 915
 916         pm_runtime_disable(&pdev->dev);
 917
 918         sh_dmae_chan_remove(shdev);
 919         shdma_cleanup(&shdev->shdma_dev);
 920
 921         synchronize_rcu();
 922
 923         return 0;
 924 }
 925
 926 static struct platform_driver sh_dmae_driver = {
 927         .driver         = {
 928                 .owner  = THIS_MODULE,
 929                 .pm     = &sh_dmae_pm,
 930                 .name   = SH_DMAE_DRV_NAME,
 931                 .of_match_table = sh_dmae_of_match,
 932         },
 933         .remove         = sh_dmae_remove,
 934         .shutdown       = sh_dmae_shutdown,
 935 };
 936
 937 static int __init sh_dmae_init(void)
 938 {
 939         /* Wire up NMI handling */
 940         int err = register_die_notifier(&sh_dmae_nmi_notifier);
 941         if (err)
 942                 return err;
 943
 944         return platform_driver_probe(&sh_dmae_driver, sh_dmae_probe);
 945 }
 946 module_init(sh_dmae_init);
 947
 948 static void __exit sh_dmae_exit(void)
 949 {
 950         platform_driver_unregister(&sh_dmae_driver);
 951
 952         unregister_die_notifier(&sh_dmae_nmi_notifier);
 953 }
 954 module_exit(sh_dmae_exit);
 955
 956 MODULE_AUTHOR("Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>");
 957 MODULE_DESCRIPTION("Renesas SH DMA Engine driver");
 958 MODULE_LICENSE("GPL");
 959 MODULE_ALIAS("platform:" SH_DMAE_DRV_NAME);