drivers/mmc/host/renesas_sdhi_sys_dmac.c

   1 /*
   2  * DMA support use of SYS DMAC with SDHI SD/SDIO controller
   3  *
   4  * Copyright (C) 2016-17 Renesas Electronics Corporation
   5  * Copyright (C) 2016-17 Sang Engineering, Wolfram Sang
   6  * Copyright (C) 2017 Horms Solutions, Simon Horman
   7  * Copyright (C) 2010-2011 Guennadi Liakhovetski
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13
  14 #include <linux/device.h>
  15 #include <linux/dma-mapping.h>
  16 #include <linux/dmaengine.h>
  17 #include <linux/mfd/tmio.h>
  18 #include <linux/mmc/host.h>
  19 #include <linux/mod_devicetable.h>
  20 #include <linux/module.h>
  21 #include <linux/of_device.h>
  22 #include <linux/pagemap.h>
  23 #include <linux/scatterlist.h>
  24 #include <linux/sys_soc.h>
  25
  26 #include "renesas_sdhi.h"
  27 #include "tmio_mmc.h"
  28
  29 #define TMIO_MMC_MIN_DMA_LEN 8
  30
  31 static const struct renesas_sdhi_of_data of_default_cfg = {
  32         .tmio_flags = TMIO_MMC_HAS_IDLE_WAIT,
  33 };
  34
  35 static const struct renesas_sdhi_of_data of_rz_compatible = {
  36         .tmio_flags     = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_32BIT_DATA_PORT |
  37                           TMIO_MMC_HAVE_CBSY,
  38         .tmio_ocr_mask  = MMC_VDD_32_33,
  39         .capabilities   = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ,
  40 };
  41
  42 static const struct renesas_sdhi_of_data of_rcar_gen1_compatible = {
  43         .tmio_flags     = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_WRPROTECT_DISABLE |
  44                           TMIO_MMC_CLK_ACTUAL,
  45         .capabilities   = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ,
  46 };
  47
  48 /* Definitions for sampling clocks */
  49 static struct renesas_sdhi_scc rcar_gen2_scc_taps[] = {
  50         {
  51                 .clk_rate = 156000000,
  52                 .tap = 0x00000703,
  53         },
  54         {
  55                 .clk_rate = 0,
  56                 .tap = 0x00000300,
  57         },
  58 };
  59
  60 static const struct renesas_sdhi_of_data of_rcar_gen2_compatible = {
  61         .tmio_flags     = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_WRPROTECT_DISABLE |
  62                           TMIO_MMC_CLK_ACTUAL | TMIO_MMC_HAVE_CBSY |
  63                           TMIO_MMC_MIN_RCAR2,
  64         .capabilities   = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
  65                           MMC_CAP_CMD23,
  66         .dma_buswidth   = DMA_SLAVE_BUSWIDTH_4_BYTES,
  67         .dma_rx_offset  = 0x2000,
  68         .scc_offset     = 0x0300,
  69         .taps           = rcar_gen2_scc_taps,
  70         .taps_num       = ARRAY_SIZE(rcar_gen2_scc_taps),
  71 };
  72
  73 /* Definitions for sampling clocks */
  74 static struct renesas_sdhi_scc rcar_gen3_scc_taps[] = {
  75         {
  76                 .clk_rate = 0,
  77                 .tap = 0x00000300,
  78         },
  79 };
  80
  81 static const struct renesas_sdhi_of_data of_rcar_gen3_compatible = {
  82         .tmio_flags     = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_WRPROTECT_DISABLE |
  83                           TMIO_MMC_CLK_ACTUAL | TMIO_MMC_HAVE_CBSY |
  84                           TMIO_MMC_MIN_RCAR2,
  85         .capabilities   = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
  86                           MMC_CAP_CMD23,
  87         .bus_shift      = 2,
  88         .scc_offset     = 0x1000,
  89         .taps           = rcar_gen3_scc_taps,
  90         .taps_num       = ARRAY_SIZE(rcar_gen3_scc_taps),
  91 };
  92
  93 static const struct of_device_id renesas_sdhi_sys_dmac_of_match[] = {
  94         { .compatible = "renesas,sdhi-shmobile" },
  95         { .compatible = "renesas,sdhi-sh73a0", .data = &of_default_cfg, },
  96         { .compatible = "renesas,sdhi-r8a73a4", .data = &of_default_cfg, },
  97         { .compatible = "renesas,sdhi-r8a7740", .data = &of_default_cfg, },
  98         { .compatible = "renesas,sdhi-r7s72100", .data = &of_rz_compatible, },
  99         { .compatible = "renesas,sdhi-r8a7778", .data = &of_rcar_gen1_compatible, },
 100         { .compatible = "renesas,sdhi-r8a7779", .data = &of_rcar_gen1_compatible, },
 101         { .compatible = "renesas,sdhi-r8a7743", .data = &of_rcar_gen2_compatible, },
 102         { .compatible = "renesas,sdhi-r8a7745", .data = &of_rcar_gen2_compatible, },
 103         { .compatible = "renesas,sdhi-r8a7790", .data = &of_rcar_gen2_compatible, },
 104         { .compatible = "renesas,sdhi-r8a7791", .data = &of_rcar_gen2_compatible, },
 105         { .compatible = "renesas,sdhi-r8a7792", .data = &of_rcar_gen2_compatible, },
 106         { .compatible = "renesas,sdhi-r8a7793", .data = &of_rcar_gen2_compatible, },
 107         { .compatible = "renesas,sdhi-r8a7794", .data = &of_rcar_gen2_compatible, },
 108         { .compatible = "renesas,sdhi-r8a7795", .data = &of_rcar_gen3_compatible, },
 109         { .compatible = "renesas,sdhi-r8a7796", .data = &of_rcar_gen3_compatible, },
 110         {},
 111 };
 112 MODULE_DEVICE_TABLE(of, renesas_sdhi_sys_dmac_of_match);
 113
 114 static void renesas_sdhi_sys_dmac_enable_dma(struct tmio_mmc_host *host,
 115                                              bool enable)
 116 {
 117         if (!host->chan_tx || !host->chan_rx)
 118                 return;
 119
 120         if (host->dma->enable)
 121                 host->dma->enable(host, enable);
 122 }
 123
 124 static void renesas_sdhi_sys_dmac_abort_dma(struct tmio_mmc_host *host)
 125 {
 126         renesas_sdhi_sys_dmac_enable_dma(host, false);
 127
 128         if (host->chan_rx)
 129                 dmaengine_terminate_all(host->chan_rx);
 130         if (host->chan_tx)
 131                 dmaengine_terminate_all(host->chan_tx);
 132
 133         renesas_sdhi_sys_dmac_enable_dma(host, true);
 134 }
 135
 136 static void renesas_sdhi_sys_dmac_dataend_dma(struct tmio_mmc_host *host)
 137 {
 138         complete(&host->dma_dataend);
 139 }
 140
 141 static void renesas_sdhi_sys_dmac_dma_callback(void *arg)
 142 {
 143         struct tmio_mmc_host *host = arg;
 144
 145         spin_lock_irq(&host->lock);
 146
 147         if (!host->data)
 148                 goto out;
 149
 150         if (host->data->flags & MMC_DATA_READ)
 151                 dma_unmap_sg(host->chan_rx->device->dev,
 152                              host->sg_ptr, host->sg_len,
 153                              DMA_FROM_DEVICE);
 154         else
 155                 dma_unmap_sg(host->chan_tx->device->dev,
 156                              host->sg_ptr, host->sg_len,
 157                              DMA_TO_DEVICE);
 158
 159         spin_unlock_irq(&host->lock);
 160
 161         wait_for_completion(&host->dma_dataend);
 162
 163         spin_lock_irq(&host->lock);
 164         tmio_mmc_do_data_irq(host);
 165 out:
 166         spin_unlock_irq(&host->lock);
 167 }
 168
 169 static void renesas_sdhi_sys_dmac_start_dma_rx(struct tmio_mmc_host *host)
 170 {
 171         struct scatterlist *sg = host->sg_ptr, *sg_tmp;
 172         struct dma_async_tx_descriptor *desc = NULL;
 173         struct dma_chan *chan = host->chan_rx;
 174         dma_cookie_t cookie;
 175         int ret, i;
 176         bool aligned = true, multiple = true;
 177         unsigned int align = (1 << host->pdata->alignment_shift) - 1;
 178
 179         for_each_sg(sg, sg_tmp, host->sg_len, i) {
 180                 if (sg_tmp->offset & align)
 181                         aligned = false;
 182                 if (sg_tmp->length & align) {
 183                         multiple = false;
 184                         break;
 185                 }
 186         }
 187
 188         if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_SIZE ||
 189                           (align & PAGE_MASK))) || !multiple) {
 190                 ret = -EINVAL;
 191                 goto pio;
 192         }
 193
 194         if (sg->length < TMIO_MMC_MIN_DMA_LEN) {
 195                 host->force_pio = true;
 196                 return;
 197         }
 198
 199         tmio_mmc_disable_mmc_irqs(host, TMIO_STAT_RXRDY);
 200
 201         /* The only sg element can be unaligned, use our bounce buffer then */
 202         if (!aligned) {
 203                 sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
 204                 host->sg_ptr = &host->bounce_sg;
 205                 sg = host->sg_ptr;
 206         }
 207
 208         ret = dma_map_sg(chan->device->dev, sg, host->sg_len, DMA_FROM_DEVICE);
 209         if (ret > 0)
 210                 desc = dmaengine_prep_slave_sg(chan, sg, ret, DMA_DEV_TO_MEM,
 211                                                DMA_CTRL_ACK);
 212
 213         if (desc) {
 214                 reinit_completion(&host->dma_dataend);
 215                 desc->callback = renesas_sdhi_sys_dmac_dma_callback;
 216                 desc->callback_param = host;
 217
 218                 cookie = dmaengine_submit(desc);
 219                 if (cookie < 0) {
 220                         desc = NULL;
 221                         ret = cookie;
 222                 }
 223         }
 224 pio:
 225         if (!desc) {
 226                 /* DMA failed, fall back to PIO */
 227                 renesas_sdhi_sys_dmac_enable_dma(host, false);
 228                 if (ret >= 0)
 229                         ret = -EIO;
 230                 host->chan_rx = NULL;
 231                 dma_release_channel(chan);
 232                 /* Free the Tx channel too */
 233                 chan = host->chan_tx;
 234                 if (chan) {
 235                         host->chan_tx = NULL;
 236                         dma_release_channel(chan);
 237                 }
 238                 dev_warn(&host->pdev->dev,
 239                          "DMA failed: %d, falling back to PIO\n", ret);
 240         }
 241 }
 242
 243 static void renesas_sdhi_sys_dmac_start_dma_tx(struct tmio_mmc_host *host)
 244 {
 245         struct scatterlist *sg = host->sg_ptr, *sg_tmp;
 246         struct dma_async_tx_descriptor *desc = NULL;
 247         struct dma_chan *chan = host->chan_tx;
 248         dma_cookie_t cookie;
 249         int ret, i;
 250         bool aligned = true, multiple = true;
 251         unsigned int align = (1 << host->pdata->alignment_shift) - 1;
 252
 253         for_each_sg(sg, sg_tmp, host->sg_len, i) {
 254                 if (sg_tmp->offset & align)
 255                         aligned = false;
 256                 if (sg_tmp->length & align) {
 257                         multiple = false;
 258                         break;
 259                 }
 260         }
 261
 262         if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_SIZE ||
 263                           (align & PAGE_MASK))) || !multiple) {
 264                 ret = -EINVAL;
 265                 goto pio;
 266         }
 267
 268         if (sg->length < TMIO_MMC_MIN_DMA_LEN) {
 269                 host->force_pio = true;
 270                 return;
 271         }
 272
 273         tmio_mmc_disable_mmc_irqs(host, TMIO_STAT_TXRQ);
 274
 275         /* The only sg element can be unaligned, use our bounce buffer then */
 276         if (!aligned) {
 277                 unsigned long flags;
 278                 void *sg_vaddr = tmio_mmc_kmap_atomic(sg, &flags);
 279
 280                 sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
 281                 memcpy(host->bounce_buf, sg_vaddr, host->bounce_sg.length);
 282                 tmio_mmc_kunmap_atomic(sg, &flags, sg_vaddr);
 283                 host->sg_ptr = &host->bounce_sg;
 284                 sg = host->sg_ptr;
 285         }
 286
 287         ret = dma_map_sg(chan->device->dev, sg, host->sg_len, DMA_TO_DEVICE);
 288         if (ret > 0)
 289                 desc = dmaengine_prep_slave_sg(chan, sg, ret, DMA_MEM_TO_DEV,
 290                                                DMA_CTRL_ACK);
 291
 292         if (desc) {
 293                 reinit_completion(&host->dma_dataend);
 294                 desc->callback = renesas_sdhi_sys_dmac_dma_callback;
 295                 desc->callback_param = host;
 296
 297                 cookie = dmaengine_submit(desc);
 298                 if (cookie < 0) {
 299                         desc = NULL;
 300                         ret = cookie;
 301                 }
 302         }
 303 pio:
 304         if (!desc) {
 305                 /* DMA failed, fall back to PIO */
 306                 renesas_sdhi_sys_dmac_enable_dma(host, false);
 307                 if (ret >= 0)
 308                         ret = -EIO;
 309                 host->chan_tx = NULL;
 310                 dma_release_channel(chan);
 311                 /* Free the Rx channel too */
 312                 chan = host->chan_rx;
 313                 if (chan) {
 314                         host->chan_rx = NULL;
 315                         dma_release_channel(chan);
 316                 }
 317                 dev_warn(&host->pdev->dev,
 318                          "DMA failed: %d, falling back to PIO\n", ret);
 319         }
 320 }
 321
 322 static void renesas_sdhi_sys_dmac_start_dma(struct tmio_mmc_host *host,
 323                                             struct mmc_data *data)
 324 {
 325         if (data->flags & MMC_DATA_READ) {
 326                 if (host->chan_rx)
 327                         renesas_sdhi_sys_dmac_start_dma_rx(host);
 328         } else {
 329                 if (host->chan_tx)
 330                         renesas_sdhi_sys_dmac_start_dma_tx(host);
 331         }
 332 }
 333
 334 static void renesas_sdhi_sys_dmac_issue_tasklet_fn(unsigned long priv)
 335 {
 336         struct tmio_mmc_host *host = (struct tmio_mmc_host *)priv;
 337         struct dma_chan *chan = NULL;
 338
 339         spin_lock_irq(&host->lock);
 340
 341         if (host && host->data) {
 342                 if (host->data->flags & MMC_DATA_READ)
 343                         chan = host->chan_rx;
 344                 else
 345                         chan = host->chan_tx;
 346         }
 347
 348         spin_unlock_irq(&host->lock);
 349
 350         tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND);
 351
 352         if (chan)
 353                 dma_async_issue_pending(chan);
 354 }
 355
 356 static void renesas_sdhi_sys_dmac_request_dma(struct tmio_mmc_host *host,
 357                                               struct tmio_mmc_data *pdata)
 358 {
 359         /* We can only either use DMA for both Tx and Rx or not use it at all */
 360         if (!host->dma || (!host->pdev->dev.of_node &&
 361                            (!pdata->chan_priv_tx || !pdata->chan_priv_rx)))
 362                 return;
 363
 364         if (!host->chan_tx && !host->chan_rx) {
 365                 struct resource *res = platform_get_resource(host->pdev,
 366                                                              IORESOURCE_MEM, 0);
 367                 struct dma_slave_config cfg = {};
 368                 dma_cap_mask_t mask;
 369                 int ret;
 370
 371                 if (!res)
 372                         return;
 373
 374                 dma_cap_zero(mask);
 375                 dma_cap_set(DMA_SLAVE, mask);
 376
 377                 host->chan_tx = dma_request_slave_channel_compat(mask,
 378                                         host->dma->filter, pdata->chan_priv_tx,
 379                                         &host->pdev->dev, "tx");
 380                 dev_dbg(&host->pdev->dev, "%s: TX: got channel %p\n", __func__,
 381                         host->chan_tx);
 382
 383                 if (!host->chan_tx)
 384                         return;
 385
 386                 cfg.direction = DMA_MEM_TO_DEV;
 387                 cfg.dst_addr = res->start +
 388                         (CTL_SD_DATA_PORT << host->bus_shift);
 389                 cfg.dst_addr_width = host->dma->dma_buswidth;
 390                 if (!cfg.dst_addr_width)
 391                         cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 392                 cfg.src_addr = 0;
 393                 ret = dmaengine_slave_config(host->chan_tx, &cfg);
 394                 if (ret < 0)
 395                         goto ecfgtx;
 396
 397                 host->chan_rx = dma_request_slave_channel_compat(mask,
 398                                         host->dma->filter, pdata->chan_priv_rx,
 399                                         &host->pdev->dev, "rx");
 400                 dev_dbg(&host->pdev->dev, "%s: RX: got channel %p\n", __func__,
 401                         host->chan_rx);
 402
 403                 if (!host->chan_rx)
 404                         goto ereqrx;
 405
 406                 cfg.direction = DMA_DEV_TO_MEM;
 407                 cfg.src_addr = cfg.dst_addr + host->pdata->dma_rx_offset;
 408                 cfg.src_addr_width = host->dma->dma_buswidth;
 409                 if (!cfg.src_addr_width)
 410                         cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 411                 cfg.dst_addr = 0;
 412                 ret = dmaengine_slave_config(host->chan_rx, &cfg);
 413                 if (ret < 0)
 414                         goto ecfgrx;
 415
 416                 host->bounce_buf = (u8 *)__get_free_page(GFP_KERNEL | GFP_DMA);
 417                 if (!host->bounce_buf)
 418                         goto ebouncebuf;
 419
 420                 init_completion(&host->dma_dataend);
 421                 tasklet_init(&host->dma_issue,
 422                              renesas_sdhi_sys_dmac_issue_tasklet_fn,
 423                              (unsigned long)host);
 424         }
 425
 426         renesas_sdhi_sys_dmac_enable_dma(host, true);
 427
 428         return;
 429
 430 ebouncebuf:
 431 ecfgrx:
 432         dma_release_channel(host->chan_rx);
 433         host->chan_rx = NULL;
 434 ereqrx:
 435 ecfgtx:
 436         dma_release_channel(host->chan_tx);
 437         host->chan_tx = NULL;
 438 }
 439
 440 static void renesas_sdhi_sys_dmac_release_dma(struct tmio_mmc_host *host)
 441 {
 442         if (host->chan_tx) {
 443                 struct dma_chan *chan = host->chan_tx;
 444
 445                 host->chan_tx = NULL;
 446                 dma_release_channel(chan);
 447         }
 448         if (host->chan_rx) {
 449                 struct dma_chan *chan = host->chan_rx;
 450
 451                 host->chan_rx = NULL;
 452                 dma_release_channel(chan);
 453         }
 454         if (host->bounce_buf) {
 455                 free_pages((unsigned long)host->bounce_buf, 0);
 456                 host->bounce_buf = NULL;
 457         }
 458 }
 459
 460 static const struct tmio_mmc_dma_ops renesas_sdhi_sys_dmac_dma_ops = {
 461         .start = renesas_sdhi_sys_dmac_start_dma,
 462         .enable = renesas_sdhi_sys_dmac_enable_dma,
 463         .request = renesas_sdhi_sys_dmac_request_dma,
 464         .release = renesas_sdhi_sys_dmac_release_dma,
 465         .abort = renesas_sdhi_sys_dmac_abort_dma,
 466         .dataend = renesas_sdhi_sys_dmac_dataend_dma,
 467 };
 468
 469 /*
 470  * Whitelist of specific R-Car Gen3 SoC ES versions to use this DMAC
 471  * implementation. Currently empty as all supported ES versions use
 472  * the internal DMAC.
 473  */
 474 static const struct soc_device_attribute gen3_soc_whitelist[] = {
 475         { /* sentinel */ }
 476 };
 477
 478 static int renesas_sdhi_sys_dmac_probe(struct platform_device *pdev)
 479 {
 480         if (of_device_get_match_data(&pdev->dev) == &of_rcar_gen3_compatible &&
 481             !soc_device_match(gen3_soc_whitelist))
 482                 return -ENODEV;
 483
 484         return renesas_sdhi_probe(pdev, &renesas_sdhi_sys_dmac_dma_ops);
 485 }
 486
 487 static const struct dev_pm_ops renesas_sdhi_sys_dmac_dev_pm_ops = {
 488         SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
 489                                 pm_runtime_force_resume)
 490         SET_RUNTIME_PM_OPS(tmio_mmc_host_runtime_suspend,
 491                            tmio_mmc_host_runtime_resume,
 492                            NULL)
 493 };
 494
 495 static struct platform_driver renesas_sys_dmac_sdhi_driver = {
 496         .driver         = {
 497                 .name   = "sh_mobile_sdhi",
 498                 .pm     = &renesas_sdhi_sys_dmac_dev_pm_ops,
 499                 .of_match_table = renesas_sdhi_sys_dmac_of_match,
 500         },
 501         .probe          = renesas_sdhi_sys_dmac_probe,
 502         .remove         = renesas_sdhi_remove,
 503 };
 504
 505 module_platform_driver(renesas_sys_dmac_sdhi_driver);
 506
 507 MODULE_DESCRIPTION("Renesas SDHI driver");
 508 MODULE_AUTHOR("Magnus Damm");
 509 MODULE_LICENSE("GPL v2");
 510 MODULE_ALIAS("platform:sh_mobile_sdhi");