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