drivers/dma/sh/rz-dmac.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Renesas RZ/G2L DMA Controller Driver
   4  *
   5  * Based on imx-dma.c
   6  *
   7  * Copyright (C) 2021 Renesas Electronics Corp.
   8  * Copyright 2010 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
   9  * Copyright 2012 Javier Martin, Vista Silicon <javier.martin@vista-silicon.com>
  10  */
  11
  12 #include <linux/bitfield.h>
  13 #include <linux/dma-mapping.h>
  14 #include <linux/dmaengine.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/iopoll.h>
  17 #include <linux/list.h>
  18 #include <linux/module.h>
  19 #include <linux/of.h>
  20 #include <linux/of_dma.h>
  21 #include <linux/of_platform.h>
  22 #include <linux/platform_device.h>
  23 #include <linux/pm_runtime.h>
  24 #include <linux/reset.h>
  25 #include <linux/slab.h>
  26 #include <linux/spinlock.h>
  27
  28 #include "../dmaengine.h"
  29 #include "../virt-dma.h"
  30
  31 enum  rz_dmac_prep_type {
  32         RZ_DMAC_DESC_MEMCPY,
  33         RZ_DMAC_DESC_SLAVE_SG,
  34 };
  35
  36 struct rz_lmdesc {
  37         u32 header;
  38         u32 sa;
  39         u32 da;
  40         u32 tb;
  41         u32 chcfg;
  42         u32 chitvl;
  43         u32 chext;
  44         u32 nxla;
  45 };
  46
  47 struct rz_dmac_desc {
  48         struct virt_dma_desc vd;
  49         dma_addr_t src;
  50         dma_addr_t dest;
  51         size_t len;
  52         struct list_head node;
  53         enum dma_transfer_direction direction;
  54         enum rz_dmac_prep_type type;
  55         /* For slave sg */
  56         struct scatterlist *sg;
  57         unsigned int sgcount;
  58 };
  59
  60 #define to_rz_dmac_desc(d)      container_of(d, struct rz_dmac_desc, vd)
  61
  62 struct rz_dmac_chan {
  63         struct virt_dma_chan vc;
  64         void __iomem *ch_base;
  65         void __iomem *ch_cmn_base;
  66         unsigned int index;
  67         int irq;
  68         struct rz_dmac_desc *desc;
  69         int descs_allocated;
  70
  71         dma_addr_t src_per_address;
  72         dma_addr_t dst_per_address;
  73
  74         u32 chcfg;
  75         u32 chctrl;
  76         int mid_rid;
  77
  78         struct list_head ld_free;
  79         struct list_head ld_queue;
  80         struct list_head ld_active;
  81
  82         struct {
  83                 struct rz_lmdesc *base;
  84                 struct rz_lmdesc *head;
  85                 struct rz_lmdesc *tail;
  86                 dma_addr_t base_dma;
  87         } lmdesc;
  88 };
  89
  90 #define to_rz_dmac_chan(c)      container_of(c, struct rz_dmac_chan, vc.chan)
  91
  92 struct rz_dmac {
  93         struct dma_device engine;
  94         struct device *dev;
  95         struct reset_control *rstc;
  96         void __iomem *base;
  97         void __iomem *ext_base;
  98
  99         unsigned int n_channels;
 100         struct rz_dmac_chan *channels;
 101
 102         DECLARE_BITMAP(modules, 1024);
 103 };
 104
 105 #define to_rz_dmac(d)   container_of(d, struct rz_dmac, engine)
 106
 107 /*
 108  * -----------------------------------------------------------------------------
 109  * Registers
 110  */
 111
 112 #define CHSTAT                          0x0024
 113 #define CHCTRL                          0x0028
 114 #define CHCFG                           0x002c
 115 #define NXLA                            0x0038
 116
 117 #define DCTRL                           0x0000
 118
 119 #define EACH_CHANNEL_OFFSET             0x0040
 120 #define CHANNEL_0_7_OFFSET              0x0000
 121 #define CHANNEL_0_7_COMMON_BASE         0x0300
 122 #define CHANNEL_8_15_OFFSET             0x0400
 123 #define CHANNEL_8_15_COMMON_BASE        0x0700
 124
 125 #define CHSTAT_ER                       BIT(4)
 126 #define CHSTAT_EN                       BIT(0)
 127
 128 #define CHCTRL_CLRINTMSK                BIT(17)
 129 #define CHCTRL_CLRSUS                   BIT(9)
 130 #define CHCTRL_CLRTC                    BIT(6)
 131 #define CHCTRL_CLREND                   BIT(5)
 132 #define CHCTRL_CLRRQ                    BIT(4)
 133 #define CHCTRL_SWRST                    BIT(3)
 134 #define CHCTRL_STG                      BIT(2)
 135 #define CHCTRL_CLREN                    BIT(1)
 136 #define CHCTRL_SETEN                    BIT(0)
 137 #define CHCTRL_DEFAULT                  (CHCTRL_CLRINTMSK | CHCTRL_CLRSUS | \
 138                                          CHCTRL_CLRTC | CHCTRL_CLREND | \
 139                                          CHCTRL_CLRRQ | CHCTRL_SWRST | \
 140                                          CHCTRL_CLREN)
 141
 142 #define CHCFG_DMS                       BIT(31)
 143 #define CHCFG_DEM                       BIT(24)
 144 #define CHCFG_DAD                       BIT(21)
 145 #define CHCFG_SAD                       BIT(20)
 146 #define CHCFG_REQD                      BIT(3)
 147 #define CHCFG_SEL(bits)                 ((bits) & 0x07)
 148 #define CHCFG_MEM_COPY                  (0x80400008)
 149 #define CHCFG_FILL_DDS_MASK             GENMASK(19, 16)
 150 #define CHCFG_FILL_SDS_MASK             GENMASK(15, 12)
 151 #define CHCFG_FILL_TM(a)                (((a) & BIT(5)) << 22)
 152 #define CHCFG_FILL_AM(a)                (((a) & GENMASK(4, 2)) << 6)
 153 #define CHCFG_FILL_LVL(a)               (((a) & BIT(1)) << 5)
 154 #define CHCFG_FILL_HIEN(a)              (((a) & BIT(0)) << 5)
 155
 156 #define MID_RID_MASK                    GENMASK(9, 0)
 157 #define CHCFG_MASK                      GENMASK(15, 10)
 158 #define CHCFG_DS_INVALID                0xFF
 159 #define DCTRL_LVINT                     BIT(1)
 160 #define DCTRL_PR                        BIT(0)
 161 #define DCTRL_DEFAULT                   (DCTRL_LVINT | DCTRL_PR)
 162
 163 /* LINK MODE DESCRIPTOR */
 164 #define HEADER_LV                       BIT(0)
 165
 166 #define RZ_DMAC_MAX_CHAN_DESCRIPTORS    16
 167 #define RZ_DMAC_MAX_CHANNELS            16
 168 #define DMAC_NR_LMDESC                  64
 169
 170 /*
 171  * -----------------------------------------------------------------------------
 172  * Device access
 173  */
 174
 175 static void rz_dmac_writel(struct rz_dmac *dmac, unsigned int val,
 176                            unsigned int offset)
 177 {
 178         writel(val, dmac->base + offset);
 179 }
 180
 181 static void rz_dmac_ext_writel(struct rz_dmac *dmac, unsigned int val,
 182                                unsigned int offset)
 183 {
 184         writel(val, dmac->ext_base + offset);
 185 }
 186
 187 static u32 rz_dmac_ext_readl(struct rz_dmac *dmac, unsigned int offset)
 188 {
 189         return readl(dmac->ext_base + offset);
 190 }
 191
 192 static void rz_dmac_ch_writel(struct rz_dmac_chan *channel, unsigned int val,
 193                               unsigned int offset, int which)
 194 {
 195         if (which)
 196                 writel(val, channel->ch_base + offset);
 197         else
 198                 writel(val, channel->ch_cmn_base + offset);
 199 }
 200
 201 static u32 rz_dmac_ch_readl(struct rz_dmac_chan *channel,
 202                             unsigned int offset, int which)
 203 {
 204         if (which)
 205                 return readl(channel->ch_base + offset);
 206         else
 207                 return readl(channel->ch_cmn_base + offset);
 208 }
 209
 210 /*
 211  * -----------------------------------------------------------------------------
 212  * Initialization
 213  */
 214
 215 static void rz_lmdesc_setup(struct rz_dmac_chan *channel,
 216                             struct rz_lmdesc *lmdesc)
 217 {
 218         u32 nxla;
 219
 220         channel->lmdesc.base = lmdesc;
 221         channel->lmdesc.head = lmdesc;
 222         channel->lmdesc.tail = lmdesc;
 223         nxla = channel->lmdesc.base_dma;
 224         while (lmdesc < (channel->lmdesc.base + (DMAC_NR_LMDESC - 1))) {
 225                 lmdesc->header = 0;
 226                 nxla += sizeof(*lmdesc);
 227                 lmdesc->nxla = nxla;
 228                 lmdesc++;
 229         }
 230
 231         lmdesc->header = 0;
 232         lmdesc->nxla = channel->lmdesc.base_dma;
 233 }
 234
 235 /*
 236  * -----------------------------------------------------------------------------
 237  * Descriptors preparation
 238  */
 239
 240 static void rz_dmac_lmdesc_recycle(struct rz_dmac_chan *channel)
 241 {
 242         struct rz_lmdesc *lmdesc = channel->lmdesc.head;
 243
 244         while (!(lmdesc->header & HEADER_LV)) {
 245                 lmdesc->header = 0;
 246                 lmdesc++;
 247                 if (lmdesc >= (channel->lmdesc.base + DMAC_NR_LMDESC))
 248                         lmdesc = channel->lmdesc.base;
 249         }
 250         channel->lmdesc.head = lmdesc;
 251 }
 252
 253 static void rz_dmac_enable_hw(struct rz_dmac_chan *channel)
 254 {
 255         struct dma_chan *chan = &channel->vc.chan;
 256         struct rz_dmac *dmac = to_rz_dmac(chan->device);
 257         unsigned long flags;
 258         u32 nxla;
 259         u32 chctrl;
 260         u32 chstat;
 261
 262         dev_dbg(dmac->dev, "%s channel %d\n", __func__, channel->index);
 263
 264         local_irq_save(flags);
 265
 266         rz_dmac_lmdesc_recycle(channel);
 267
 268         nxla = channel->lmdesc.base_dma +
 269                 (sizeof(struct rz_lmdesc) * (channel->lmdesc.head -
 270                                              channel->lmdesc.base));
 271
 272         chstat = rz_dmac_ch_readl(channel, CHSTAT, 1);
 273         if (!(chstat & CHSTAT_EN)) {
 274                 chctrl = (channel->chctrl | CHCTRL_SETEN);
 275                 rz_dmac_ch_writel(channel, nxla, NXLA, 1);
 276                 rz_dmac_ch_writel(channel, channel->chcfg, CHCFG, 1);
 277                 rz_dmac_ch_writel(channel, CHCTRL_SWRST, CHCTRL, 1);
 278                 rz_dmac_ch_writel(channel, chctrl, CHCTRL, 1);
 279         }
 280
 281         local_irq_restore(flags);
 282 }
 283
 284 static void rz_dmac_disable_hw(struct rz_dmac_chan *channel)
 285 {
 286         struct dma_chan *chan = &channel->vc.chan;
 287         struct rz_dmac *dmac = to_rz_dmac(chan->device);
 288         unsigned long flags;
 289
 290         dev_dbg(dmac->dev, "%s channel %d\n", __func__, channel->index);
 291
 292         local_irq_save(flags);
 293         rz_dmac_ch_writel(channel, CHCTRL_DEFAULT, CHCTRL, 1);
 294         local_irq_restore(flags);
 295 }
 296
 297 static void rz_dmac_set_dmars_register(struct rz_dmac *dmac, int nr, u32 dmars)
 298 {
 299         u32 dmars_offset = (nr / 2) * 4;
 300         u32 shift = (nr % 2) * 16;
 301         u32 dmars32;
 302
 303         dmars32 = rz_dmac_ext_readl(dmac, dmars_offset);
 304         dmars32 &= ~(0xffff << shift);
 305         dmars32 |= dmars << shift;
 306
 307         rz_dmac_ext_writel(dmac, dmars32, dmars_offset);
 308 }
 309
 310 static void rz_dmac_prepare_desc_for_memcpy(struct rz_dmac_chan *channel)
 311 {
 312         struct dma_chan *chan = &channel->vc.chan;
 313         struct rz_dmac *dmac = to_rz_dmac(chan->device);
 314         struct rz_lmdesc *lmdesc = channel->lmdesc.tail;
 315         struct rz_dmac_desc *d = channel->desc;
 316         u32 chcfg = CHCFG_MEM_COPY;
 317
 318         /* prepare descriptor */
 319         lmdesc->sa = d->src;
 320         lmdesc->da = d->dest;
 321         lmdesc->tb = d->len;
 322         lmdesc->chcfg = chcfg;
 323         lmdesc->chitvl = 0;
 324         lmdesc->chext = 0;
 325         lmdesc->header = HEADER_LV;
 326
 327         rz_dmac_set_dmars_register(dmac, channel->index, 0);
 328
 329         channel->chcfg = chcfg;
 330         channel->chctrl = CHCTRL_STG | CHCTRL_SETEN;
 331 }
 332
 333 static void rz_dmac_prepare_descs_for_slave_sg(struct rz_dmac_chan *channel)
 334 {
 335         struct dma_chan *chan = &channel->vc.chan;
 336         struct rz_dmac *dmac = to_rz_dmac(chan->device);
 337         struct rz_dmac_desc *d = channel->desc;
 338         struct scatterlist *sg, *sgl = d->sg;
 339         struct rz_lmdesc *lmdesc;
 340         unsigned int i, sg_len = d->sgcount;
 341
 342         channel->chcfg |= CHCFG_SEL(channel->index) | CHCFG_DEM | CHCFG_DMS;
 343
 344         if (d->direction == DMA_DEV_TO_MEM) {
 345                 channel->chcfg |= CHCFG_SAD;
 346                 channel->chcfg &= ~CHCFG_REQD;
 347         } else {
 348                 channel->chcfg |= CHCFG_DAD | CHCFG_REQD;
 349         }
 350
 351         lmdesc = channel->lmdesc.tail;
 352
 353         for (i = 0, sg = sgl; i < sg_len; i++, sg = sg_next(sg)) {
 354                 if (d->direction == DMA_DEV_TO_MEM) {
 355                         lmdesc->sa = channel->src_per_address;
 356                         lmdesc->da = sg_dma_address(sg);
 357                 } else {
 358                         lmdesc->sa = sg_dma_address(sg);
 359                         lmdesc->da = channel->dst_per_address;
 360                 }
 361
 362                 lmdesc->tb = sg_dma_len(sg);
 363                 lmdesc->chitvl = 0;
 364                 lmdesc->chext = 0;
 365                 if (i == (sg_len - 1)) {
 366                         lmdesc->chcfg = (channel->chcfg & ~CHCFG_DEM);
 367                         lmdesc->header = HEADER_LV;
 368                 } else {
 369                         lmdesc->chcfg = channel->chcfg;
 370                         lmdesc->header = HEADER_LV;
 371                 }
 372                 if (++lmdesc >= (channel->lmdesc.base + DMAC_NR_LMDESC))
 373                         lmdesc = channel->lmdesc.base;
 374         }
 375
 376         channel->lmdesc.tail = lmdesc;
 377
 378         rz_dmac_set_dmars_register(dmac, channel->index, channel->mid_rid);
 379         channel->chctrl = CHCTRL_SETEN;
 380 }
 381
 382 static int rz_dmac_xfer_desc(struct rz_dmac_chan *chan)
 383 {
 384         struct rz_dmac_desc *d = chan->desc;
 385         struct virt_dma_desc *vd;
 386
 387         vd = vchan_next_desc(&chan->vc);
 388         if (!vd)
 389                 return 0;
 390
 391         list_del(&vd->node);
 392
 393         switch (d->type) {
 394         case RZ_DMAC_DESC_MEMCPY:
 395                 rz_dmac_prepare_desc_for_memcpy(chan);
 396                 break;
 397
 398         case RZ_DMAC_DESC_SLAVE_SG:
 399                 rz_dmac_prepare_descs_for_slave_sg(chan);
 400                 break;
 401
 402         default:
 403                 return -EINVAL;
 404         }
 405
 406         rz_dmac_enable_hw(chan);
 407
 408         return 0;
 409 }
 410
 411 /*
 412  * -----------------------------------------------------------------------------
 413  * DMA engine operations
 414  */
 415
 416 static int rz_dmac_alloc_chan_resources(struct dma_chan *chan)
 417 {
 418         struct rz_dmac_chan *channel = to_rz_dmac_chan(chan);
 419
 420         while (channel->descs_allocated < RZ_DMAC_MAX_CHAN_DESCRIPTORS) {
 421                 struct rz_dmac_desc *desc;
 422
 423                 desc = kzalloc(sizeof(*desc), GFP_KERNEL);
 424                 if (!desc)
 425                         break;
 426
 427                 list_add_tail(&desc->node, &channel->ld_free);
 428                 channel->descs_allocated++;
 429         }
 430
 431         if (!channel->descs_allocated)
 432                 return -ENOMEM;
 433
 434         return channel->descs_allocated;
 435 }
 436
 437 static void rz_dmac_free_chan_resources(struct dma_chan *chan)
 438 {
 439         struct rz_dmac_chan *channel = to_rz_dmac_chan(chan);
 440         struct rz_dmac *dmac = to_rz_dmac(chan->device);
 441         struct rz_lmdesc *lmdesc = channel->lmdesc.base;
 442         struct rz_dmac_desc *desc, *_desc;
 443         unsigned long flags;
 444         unsigned int i;
 445
 446         spin_lock_irqsave(&channel->vc.lock, flags);
 447
 448         for (i = 0; i < DMAC_NR_LMDESC; i++)
 449                 lmdesc[i].header = 0;
 450
 451         rz_dmac_disable_hw(channel);
 452         list_splice_tail_init(&channel->ld_active, &channel->ld_free);
 453         list_splice_tail_init(&channel->ld_queue, &channel->ld_free);
 454
 455         if (channel->mid_rid >= 0) {
 456                 clear_bit(channel->mid_rid, dmac->modules);
 457                 channel->mid_rid = -EINVAL;
 458         }
 459
 460         spin_unlock_irqrestore(&channel->vc.lock, flags);
 461
 462         list_for_each_entry_safe(desc, _desc, &channel->ld_free, node) {
 463                 kfree(desc);
 464                 channel->descs_allocated--;
 465         }
 466
 467         INIT_LIST_HEAD(&channel->ld_free);
 468         vchan_free_chan_resources(&channel->vc);
 469 }
 470
 471 static struct dma_async_tx_descriptor *
 472 rz_dmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
 473                         size_t len, unsigned long flags)
 474 {
 475         struct rz_dmac_chan *channel = to_rz_dmac_chan(chan);
 476         struct rz_dmac *dmac = to_rz_dmac(chan->device);
 477         struct rz_dmac_desc *desc;
 478
 479         dev_dbg(dmac->dev, "%s channel: %d src=0x%pad dst=0x%pad len=%zu\n",
 480                 __func__, channel->index, &src, &dest, len);
 481
 482         if (list_empty(&channel->ld_free))
 483                 return NULL;
 484
 485         desc = list_first_entry(&channel->ld_free, struct rz_dmac_desc, node);
 486
 487         desc->type = RZ_DMAC_DESC_MEMCPY;
 488         desc->src = src;
 489         desc->dest = dest;
 490         desc->len = len;
 491         desc->direction = DMA_MEM_TO_MEM;
 492
 493         list_move_tail(channel->ld_free.next, &channel->ld_queue);
 494         return vchan_tx_prep(&channel->vc, &desc->vd, flags);
 495 }
 496
 497 static struct dma_async_tx_descriptor *
 498 rz_dmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 499                       unsigned int sg_len,
 500                       enum dma_transfer_direction direction,
 501                       unsigned long flags, void *context)
 502 {
 503         struct rz_dmac_chan *channel = to_rz_dmac_chan(chan);
 504         struct rz_dmac_desc *desc;
 505         struct scatterlist *sg;
 506         int dma_length = 0;
 507         int i = 0;
 508
 509         if (list_empty(&channel->ld_free))
 510                 return NULL;
 511
 512         desc = list_first_entry(&channel->ld_free, struct rz_dmac_desc, node);
 513
 514         for_each_sg(sgl, sg, sg_len, i) {
 515                 dma_length += sg_dma_len(sg);
 516         }
 517
 518         desc->type = RZ_DMAC_DESC_SLAVE_SG;
 519         desc->sg = sgl;
 520         desc->sgcount = sg_len;
 521         desc->len = dma_length;
 522         desc->direction = direction;
 523
 524         if (direction == DMA_DEV_TO_MEM)
 525                 desc->src = channel->src_per_address;
 526         else
 527                 desc->dest = channel->dst_per_address;
 528
 529         list_move_tail(channel->ld_free.next, &channel->ld_queue);
 530         return vchan_tx_prep(&channel->vc, &desc->vd, flags);
 531 }
 532
 533 static int rz_dmac_terminate_all(struct dma_chan *chan)
 534 {
 535         struct rz_dmac_chan *channel = to_rz_dmac_chan(chan);
 536         unsigned long flags;
 537         LIST_HEAD(head);
 538
 539         rz_dmac_disable_hw(channel);
 540         spin_lock_irqsave(&channel->vc.lock, flags);
 541         list_splice_tail_init(&channel->ld_active, &channel->ld_free);
 542         list_splice_tail_init(&channel->ld_queue, &channel->ld_free);
 543         spin_unlock_irqrestore(&channel->vc.lock, flags);
 544         vchan_get_all_descriptors(&channel->vc, &head);
 545         vchan_dma_desc_free_list(&channel->vc, &head);
 546
 547         return 0;
 548 }
 549
 550 static void rz_dmac_issue_pending(struct dma_chan *chan)
 551 {
 552         struct rz_dmac_chan *channel = to_rz_dmac_chan(chan);
 553         struct rz_dmac *dmac = to_rz_dmac(chan->device);
 554         struct rz_dmac_desc *desc;
 555         unsigned long flags;
 556
 557         spin_lock_irqsave(&channel->vc.lock, flags);
 558
 559         if (!list_empty(&channel->ld_queue)) {
 560                 desc = list_first_entry(&channel->ld_queue,
 561                                         struct rz_dmac_desc, node);
 562                 channel->desc = desc;
 563                 if (vchan_issue_pending(&channel->vc)) {
 564                         if (rz_dmac_xfer_desc(channel) < 0)
 565                                 dev_warn(dmac->dev, "ch: %d couldn't issue DMA xfer\n",
 566                                          channel->index);
 567                         else
 568                                 list_move_tail(channel->ld_queue.next,
 569                                                &channel->ld_active);
 570                 }
 571         }
 572
 573         spin_unlock_irqrestore(&channel->vc.lock, flags);
 574 }
 575
 576 static u8 rz_dmac_ds_to_val_mapping(enum dma_slave_buswidth ds)
 577 {
 578         u8 i;
 579         static const enum dma_slave_buswidth ds_lut[] = {
 580                 DMA_SLAVE_BUSWIDTH_1_BYTE,
 581                 DMA_SLAVE_BUSWIDTH_2_BYTES,
 582                 DMA_SLAVE_BUSWIDTH_4_BYTES,
 583                 DMA_SLAVE_BUSWIDTH_8_BYTES,
 584                 DMA_SLAVE_BUSWIDTH_16_BYTES,
 585                 DMA_SLAVE_BUSWIDTH_32_BYTES,
 586                 DMA_SLAVE_BUSWIDTH_64_BYTES,
 587                 DMA_SLAVE_BUSWIDTH_128_BYTES,
 588         };
 589
 590         for (i = 0; i < ARRAY_SIZE(ds_lut); i++) {
 591                 if (ds_lut[i] == ds)
 592                         return i;
 593         }
 594
 595         return CHCFG_DS_INVALID;
 596 }
 597
 598 static int rz_dmac_config(struct dma_chan *chan,
 599                           struct dma_slave_config *config)
 600 {
 601         struct rz_dmac_chan *channel = to_rz_dmac_chan(chan);
 602         u32 val;
 603
 604         channel->src_per_address = config->src_addr;
 605         channel->dst_per_address = config->dst_addr;
 606
 607         val = rz_dmac_ds_to_val_mapping(config->dst_addr_width);
 608         if (val == CHCFG_DS_INVALID)
 609                 return -EINVAL;
 610
 611         channel->chcfg &= ~CHCFG_FILL_DDS_MASK;
 612         channel->chcfg |= FIELD_PREP(CHCFG_FILL_DDS_MASK, val);
 613
 614         val = rz_dmac_ds_to_val_mapping(config->src_addr_width);
 615         if (val == CHCFG_DS_INVALID)
 616                 return -EINVAL;
 617
 618         channel->chcfg &= ~CHCFG_FILL_SDS_MASK;
 619         channel->chcfg |= FIELD_PREP(CHCFG_FILL_SDS_MASK, val);
 620
 621         return 0;
 622 }
 623
 624 static void rz_dmac_virt_desc_free(struct virt_dma_desc *vd)
 625 {
 626         /*
 627          * Place holder
 628          * Descriptor allocation is done during alloc_chan_resources and
 629          * get freed during free_chan_resources.
 630          * list is used to manage the descriptors and avoid any memory
 631          * allocation/free during DMA read/write.
 632          */
 633 }
 634
 635 static void rz_dmac_device_synchronize(struct dma_chan *chan)
 636 {
 637         struct rz_dmac_chan *channel = to_rz_dmac_chan(chan);
 638         struct rz_dmac *dmac = to_rz_dmac(chan->device);
 639         u32 chstat;
 640         int ret;
 641
 642         ret = read_poll_timeout(rz_dmac_ch_readl, chstat, !(chstat & CHSTAT_EN),
 643                                 100, 100000, false, channel, CHSTAT, 1);
 644         if (ret < 0)
 645                 dev_warn(dmac->dev, "DMA Timeout");
 646
 647         rz_dmac_set_dmars_register(dmac, channel->index, 0);
 648 }
 649
 650 /*
 651  * -----------------------------------------------------------------------------
 652  * IRQ handling
 653  */
 654
 655 static void rz_dmac_irq_handle_channel(struct rz_dmac_chan *channel)
 656 {
 657         struct dma_chan *chan = &channel->vc.chan;
 658         struct rz_dmac *dmac = to_rz_dmac(chan->device);
 659         u32 chstat, chctrl;
 660
 661         chstat = rz_dmac_ch_readl(channel, CHSTAT, 1);
 662         if (chstat & CHSTAT_ER) {
 663                 dev_err(dmac->dev, "DMAC err CHSTAT_%d = %08X\n",
 664                         channel->index, chstat);
 665                 rz_dmac_ch_writel(channel, CHCTRL_DEFAULT, CHCTRL, 1);
 666                 goto done;
 667         }
 668
 669         chctrl = rz_dmac_ch_readl(channel, CHCTRL, 1);
 670         rz_dmac_ch_writel(channel, chctrl | CHCTRL_CLREND, CHCTRL, 1);
 671 done:
 672         return;
 673 }
 674
 675 static irqreturn_t rz_dmac_irq_handler(int irq, void *dev_id)
 676 {
 677         struct rz_dmac_chan *channel = dev_id;
 678
 679         if (channel) {
 680                 rz_dmac_irq_handle_channel(channel);
 681                 return IRQ_WAKE_THREAD;
 682         }
 683         /* handle DMAERR irq */
 684         return IRQ_HANDLED;
 685 }
 686
 687 static irqreturn_t rz_dmac_irq_handler_thread(int irq, void *dev_id)
 688 {
 689         struct rz_dmac_chan *channel = dev_id;
 690         struct rz_dmac_desc *desc = NULL;
 691         unsigned long flags;
 692
 693         spin_lock_irqsave(&channel->vc.lock, flags);
 694
 695         if (list_empty(&channel->ld_active)) {
 696                 /* Someone might have called terminate all */
 697                 goto out;
 698         }
 699
 700         desc = list_first_entry(&channel->ld_active, struct rz_dmac_desc, node);
 701         vchan_cookie_complete(&desc->vd);
 702         list_move_tail(channel->ld_active.next, &channel->ld_free);
 703         if (!list_empty(&channel->ld_queue)) {
 704                 desc = list_first_entry(&channel->ld_queue, struct rz_dmac_desc,
 705                                         node);
 706                 channel->desc = desc;
 707                 if (rz_dmac_xfer_desc(channel) == 0)
 708                         list_move_tail(channel->ld_queue.next, &channel->ld_active);
 709         }
 710 out:
 711         spin_unlock_irqrestore(&channel->vc.lock, flags);
 712
 713         return IRQ_HANDLED;
 714 }
 715
 716 /*
 717  * -----------------------------------------------------------------------------
 718  * OF xlate and channel filter
 719  */
 720
 721 static bool rz_dmac_chan_filter(struct dma_chan *chan, void *arg)
 722 {
 723         struct rz_dmac_chan *channel = to_rz_dmac_chan(chan);
 724         struct rz_dmac *dmac = to_rz_dmac(chan->device);
 725         struct of_phandle_args *dma_spec = arg;
 726         u32 ch_cfg;
 727
 728         channel->mid_rid = dma_spec->args[0] & MID_RID_MASK;
 729         ch_cfg = (dma_spec->args[0] & CHCFG_MASK) >> 10;
 730         channel->chcfg = CHCFG_FILL_TM(ch_cfg) | CHCFG_FILL_AM(ch_cfg) |
 731                          CHCFG_FILL_LVL(ch_cfg) | CHCFG_FILL_HIEN(ch_cfg);
 732
 733         return !test_and_set_bit(channel->mid_rid, dmac->modules);
 734 }
 735
 736 static struct dma_chan *rz_dmac_of_xlate(struct of_phandle_args *dma_spec,
 737                                          struct of_dma *ofdma)
 738 {
 739         dma_cap_mask_t mask;
 740
 741         if (dma_spec->args_count != 1)
 742                 return NULL;
 743
 744         /* Only slave DMA channels can be allocated via DT */
 745         dma_cap_zero(mask);
 746         dma_cap_set(DMA_SLAVE, mask);
 747
 748         return dma_request_channel(mask, rz_dmac_chan_filter, dma_spec);
 749 }
 750
 751 /*
 752  * -----------------------------------------------------------------------------
 753  * Probe and remove
 754  */
 755
 756 static int rz_dmac_chan_probe(struct rz_dmac *dmac,
 757                               struct rz_dmac_chan *channel,
 758                               u8 index)
 759 {
 760         struct platform_device *pdev = to_platform_device(dmac->dev);
 761         struct rz_lmdesc *lmdesc;
 762         char pdev_irqname[6];
 763         char *irqname;
 764         int ret;
 765
 766         channel->index = index;
 767         channel->mid_rid = -EINVAL;
 768
 769         /* Request the channel interrupt. */
 770         scnprintf(pdev_irqname, sizeof(pdev_irqname), "ch%u", index);
 771         channel->irq = platform_get_irq_byname(pdev, pdev_irqname);
 772         if (channel->irq < 0)
 773                 return channel->irq;
 774
 775         irqname = devm_kasprintf(dmac->dev, GFP_KERNEL, "%s:%u",
 776                                  dev_name(dmac->dev), index);
 777         if (!irqname)
 778                 return -ENOMEM;
 779
 780         ret = devm_request_threaded_irq(dmac->dev, channel->irq,
 781                                         rz_dmac_irq_handler,
 782                                         rz_dmac_irq_handler_thread, 0,
 783                                         irqname, channel);
 784         if (ret) {
 785                 dev_err(dmac->dev, "failed to request IRQ %u (%d)\n",
 786                         channel->irq, ret);
 787                 return ret;
 788         }
 789
 790         /* Set io base address for each channel */
 791         if (index < 8) {
 792                 channel->ch_base = dmac->base + CHANNEL_0_7_OFFSET +
 793                         EACH_CHANNEL_OFFSET * index;
 794                 channel->ch_cmn_base = dmac->base + CHANNEL_0_7_COMMON_BASE;
 795         } else {
 796                 channel->ch_base = dmac->base + CHANNEL_8_15_OFFSET +
 797                         EACH_CHANNEL_OFFSET * (index - 8);
 798                 channel->ch_cmn_base = dmac->base + CHANNEL_8_15_COMMON_BASE;
 799         }
 800
 801         /* Allocate descriptors */
 802         lmdesc = dma_alloc_coherent(&pdev->dev,
 803                                     sizeof(struct rz_lmdesc) * DMAC_NR_LMDESC,
 804                                     &channel->lmdesc.base_dma, GFP_KERNEL);
 805         if (!lmdesc) {
 806                 dev_err(&pdev->dev, "Can't allocate memory (lmdesc)\n");
 807                 return -ENOMEM;
 808         }
 809         rz_lmdesc_setup(channel, lmdesc);
 810
 811         /* Initialize register for each channel */
 812         rz_dmac_ch_writel(channel, CHCTRL_DEFAULT, CHCTRL, 1);
 813
 814         channel->vc.desc_free = rz_dmac_virt_desc_free;
 815         vchan_init(&channel->vc, &dmac->engine);
 816         INIT_LIST_HEAD(&channel->ld_queue);
 817         INIT_LIST_HEAD(&channel->ld_free);
 818         INIT_LIST_HEAD(&channel->ld_active);
 819
 820         return 0;
 821 }
 822
 823 static int rz_dmac_parse_of(struct device *dev, struct rz_dmac *dmac)
 824 {
 825         struct device_node *np = dev->of_node;
 826         int ret;
 827
 828         ret = of_property_read_u32(np, "dma-channels", &dmac->n_channels);
 829         if (ret < 0) {
 830                 dev_err(dev, "unable to read dma-channels property\n");
 831                 return ret;
 832         }
 833
 834         if (!dmac->n_channels || dmac->n_channels > RZ_DMAC_MAX_CHANNELS) {
 835                 dev_err(dev, "invalid number of channels %u\n", dmac->n_channels);
 836                 return -EINVAL;
 837         }
 838
 839         return 0;
 840 }
 841
 842 static int rz_dmac_probe(struct platform_device *pdev)
 843 {
 844         const char *irqname = "error";
 845         struct dma_device *engine;
 846         struct rz_dmac *dmac;
 847         int channel_num;
 848         int ret;
 849         int irq;
 850         u8 i;
 851
 852         dmac = devm_kzalloc(&pdev->dev, sizeof(*dmac), GFP_KERNEL);
 853         if (!dmac)
 854                 return -ENOMEM;
 855
 856         dmac->dev = &pdev->dev;
 857         platform_set_drvdata(pdev, dmac);
 858
 859         ret = rz_dmac_parse_of(&pdev->dev, dmac);
 860         if (ret < 0)
 861                 return ret;
 862
 863         dmac->channels = devm_kcalloc(&pdev->dev, dmac->n_channels,
 864                                       sizeof(*dmac->channels), GFP_KERNEL);
 865         if (!dmac->channels)
 866                 return -ENOMEM;
 867
 868         /* Request resources */
 869         dmac->base = devm_platform_ioremap_resource(pdev, 0);
 870         if (IS_ERR(dmac->base))
 871                 return PTR_ERR(dmac->base);
 872
 873         dmac->ext_base = devm_platform_ioremap_resource(pdev, 1);
 874         if (IS_ERR(dmac->ext_base))
 875                 return PTR_ERR(dmac->ext_base);
 876
 877         /* Register interrupt handler for error */
 878         irq = platform_get_irq_byname(pdev, irqname);
 879         if (irq < 0)
 880                 return irq;
 881
 882         ret = devm_request_irq(&pdev->dev, irq, rz_dmac_irq_handler, 0,
 883                                irqname, NULL);
 884         if (ret) {
 885                 dev_err(&pdev->dev, "failed to request IRQ %u (%d)\n",
 886                         irq, ret);
 887                 return ret;
 888         }
 889
 890         /* Initialize the channels. */
 891         INIT_LIST_HEAD(&dmac->engine.channels);
 892
 893         dmac->rstc = devm_reset_control_array_get_exclusive(&pdev->dev);
 894         if (IS_ERR(dmac->rstc))
 895                 return dev_err_probe(&pdev->dev, PTR_ERR(dmac->rstc),
 896                                      "failed to get resets\n");
 897
 898         pm_runtime_enable(&pdev->dev);
 899         ret = pm_runtime_resume_and_get(&pdev->dev);
 900         if (ret < 0) {
 901                 dev_err(&pdev->dev, "pm_runtime_resume_and_get failed\n");
 902                 goto err_pm_disable;
 903         }
 904
 905         ret = reset_control_deassert(dmac->rstc);
 906         if (ret)
 907                 goto err_pm_runtime_put;
 908
 909         for (i = 0; i < dmac->n_channels; i++) {
 910                 ret = rz_dmac_chan_probe(dmac, &dmac->channels[i], i);
 911                 if (ret < 0)
 912                         goto err;
 913         }
 914
 915         /* Register the DMAC as a DMA provider for DT. */
 916         ret = of_dma_controller_register(pdev->dev.of_node, rz_dmac_of_xlate,
 917                                          NULL);
 918         if (ret < 0)
 919                 goto err;
 920
 921         /* Register the DMA engine device. */
 922         engine = &dmac->engine;
 923         dma_cap_set(DMA_SLAVE, engine->cap_mask);
 924         dma_cap_set(DMA_MEMCPY, engine->cap_mask);
 925         rz_dmac_writel(dmac, DCTRL_DEFAULT, CHANNEL_0_7_COMMON_BASE + DCTRL);
 926         rz_dmac_writel(dmac, DCTRL_DEFAULT, CHANNEL_8_15_COMMON_BASE + DCTRL);
 927
 928         engine->dev = &pdev->dev;
 929
 930         engine->device_alloc_chan_resources = rz_dmac_alloc_chan_resources;
 931         engine->device_free_chan_resources = rz_dmac_free_chan_resources;
 932         engine->device_tx_status = dma_cookie_status;
 933         engine->device_prep_slave_sg = rz_dmac_prep_slave_sg;
 934         engine->device_prep_dma_memcpy = rz_dmac_prep_dma_memcpy;
 935         engine->device_config = rz_dmac_config;
 936         engine->device_terminate_all = rz_dmac_terminate_all;
 937         engine->device_issue_pending = rz_dmac_issue_pending;
 938         engine->device_synchronize = rz_dmac_device_synchronize;
 939
 940         engine->copy_align = DMAENGINE_ALIGN_1_BYTE;
 941         dma_set_max_seg_size(engine->dev, U32_MAX);
 942
 943         ret = dma_async_device_register(engine);
 944         if (ret < 0) {
 945                 dev_err(&pdev->dev, "unable to register\n");
 946                 goto dma_register_err;
 947         }
 948         return 0;
 949
 950 dma_register_err:
 951         of_dma_controller_free(pdev->dev.of_node);
 952 err:
 953         channel_num = i ? i - 1 : 0;
 954         for (i = 0; i < channel_num; i++) {
 955                 struct rz_dmac_chan *channel = &dmac->channels[i];
 956
 957                 dma_free_coherent(&pdev->dev,
 958                                   sizeof(struct rz_lmdesc) * DMAC_NR_LMDESC,
 959                                   channel->lmdesc.base,
 960                                   channel->lmdesc.base_dma);
 961         }
 962
 963         reset_control_assert(dmac->rstc);
 964 err_pm_runtime_put:
 965         pm_runtime_put(&pdev->dev);
 966 err_pm_disable:
 967         pm_runtime_disable(&pdev->dev);
 968
 969         return ret;
 970 }
 971
 972 static void rz_dmac_remove(struct platform_device *pdev)
 973 {
 974         struct rz_dmac *dmac = platform_get_drvdata(pdev);
 975         unsigned int i;
 976
 977         dma_async_device_unregister(&dmac->engine);
 978         of_dma_controller_free(pdev->dev.of_node);
 979         for (i = 0; i < dmac->n_channels; i++) {
 980                 struct rz_dmac_chan *channel = &dmac->channels[i];
 981
 982                 dma_free_coherent(&pdev->dev,
 983                                   sizeof(struct rz_lmdesc) * DMAC_NR_LMDESC,
 984                                   channel->lmdesc.base,
 985                                   channel->lmdesc.base_dma);
 986         }
 987         reset_control_assert(dmac->rstc);
 988         pm_runtime_put(&pdev->dev);
 989         pm_runtime_disable(&pdev->dev);
 990 }
 991
 992 static const struct of_device_id of_rz_dmac_match[] = {
 993         { .compatible = "renesas,rz-dmac", },
 994         { /* Sentinel */ }
 995 };
 996 MODULE_DEVICE_TABLE(of, of_rz_dmac_match);
 997
 998 static struct platform_driver rz_dmac_driver = {
 999         .driver         = {
1000                 .name   = "rz-dmac",
1001                 .of_match_table = of_rz_dmac_match,
1002         },
1003         .probe          = rz_dmac_probe,
1004         .remove_new     = rz_dmac_remove,
1005 };
1006
1007 module_platform_driver(rz_dmac_driver);
1008
1009 MODULE_DESCRIPTION("Renesas RZ/G2L DMA Controller Driver");
1010 MODULE_AUTHOR("Biju Das <biju.das.jz@bp.renesas.com>");
1011 MODULE_LICENSE("GPL v2");