linux/drivers/mmc/host/renesas_sdhi_sys_dmac.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * DMA support use of SYS DMAC with SDHI SD/SDIO controller
   4 *
   5 * Copyright (C) 2016-19 Renesas Electronics Corporation
   6 * Copyright (C) 2016-19 Sang Engineering, Wolfram Sang
   7 * Copyright (C) 2017 Horms Solutions, Simon Horman
   8 * Copyright (C) 2010-2011 Guennadi Liakhovetski
   9 */
  10
  11#include <linux/device.h>
  12#include <linux/dma-mapping.h>
  13#include <linux/dmaengine.h>
  14#include <linux/mfd/tmio.h>
  15#include <linux/mmc/host.h>
  16#include <linux/mod_devicetable.h>
  17#include <linux/module.h>
  18#include <linux/of_device.h>
  19#include <linux/pagemap.h>
  20#include <linux/scatterlist.h>
  21#include <linux/sys_soc.h>
  22
  23#include "renesas_sdhi.h"
  24#include "tmio_mmc.h"
  25
  26#define TMIO_MMC_MIN_DMA_LEN 8
  27
  28static const struct renesas_sdhi_of_data of_default_cfg = {
  29        .tmio_flags = TMIO_MMC_HAS_IDLE_WAIT,
  30};
  31
  32static const struct renesas_sdhi_of_data of_rz_compatible = {
  33        .tmio_flags     = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_32BIT_DATA_PORT |
  34                          TMIO_MMC_HAVE_CBSY,
  35        .tmio_ocr_mask  = MMC_VDD_32_33,
  36        .capabilities   = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
  37                          MMC_CAP_WAIT_WHILE_BUSY,
  38};
  39
  40static const struct renesas_sdhi_of_data of_rcar_gen1_compatible = {
  41        .tmio_flags     = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_CLK_ACTUAL,
  42        .capabilities   = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
  43                          MMC_CAP_WAIT_WHILE_BUSY,
  44        .capabilities2  = MMC_CAP2_NO_WRITE_PROTECT,
  45};
  46
  47/* Definitions for sampling clocks */
  48static 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
  59static const struct renesas_sdhi_of_data of_rcar_gen2_compatible = {
  60        .tmio_flags     = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_CLK_ACTUAL |
  61                          TMIO_MMC_HAVE_CBSY | TMIO_MMC_MIN_RCAR2,
  62        .capabilities   = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ |
  63                          MMC_CAP_CMD23 | MMC_CAP_WAIT_WHILE_BUSY,
  64        .capabilities2  = MMC_CAP2_NO_WRITE_PROTECT,
  65        .dma_buswidth   = DMA_SLAVE_BUSWIDTH_4_BYTES,
  66        .dma_rx_offset  = 0x2000,
  67        .scc_offset     = 0x0300,
  68        .taps           = rcar_gen2_scc_taps,
  69        .taps_num       = ARRAY_SIZE(rcar_gen2_scc_taps),
  70        .max_blk_count  = UINT_MAX / TMIO_MAX_BLK_SIZE,
  71};
  72
  73static const struct of_device_id renesas_sdhi_sys_dmac_of_match[] = {
  74        { .compatible = "renesas,sdhi-sh73a0", .data = &of_default_cfg, },
  75        { .compatible = "renesas,sdhi-r8a73a4", .data = &of_default_cfg, },
  76        { .compatible = "renesas,sdhi-r8a7740", .data = &of_default_cfg, },
  77        { .compatible = "renesas,sdhi-r7s72100", .data = &of_rz_compatible, },
  78        { .compatible = "renesas,sdhi-r8a7778", .data = &of_rcar_gen1_compatible, },
  79        { .compatible = "renesas,sdhi-r8a7779", .data = &of_rcar_gen1_compatible, },
  80        { .compatible = "renesas,sdhi-r8a7743", .data = &of_rcar_gen2_compatible, },
  81        { .compatible = "renesas,sdhi-r8a7745", .data = &of_rcar_gen2_compatible, },
  82        { .compatible = "renesas,sdhi-r8a7790", .data = &of_rcar_gen2_compatible, },
  83        { .compatible = "renesas,sdhi-r8a7791", .data = &of_rcar_gen2_compatible, },
  84        { .compatible = "renesas,sdhi-r8a7792", .data = &of_rcar_gen2_compatible, },
  85        { .compatible = "renesas,sdhi-r8a7793", .data = &of_rcar_gen2_compatible, },
  86        { .compatible = "renesas,sdhi-r8a7794", .data = &of_rcar_gen2_compatible, },
  87        { .compatible = "renesas,rcar-gen1-sdhi", .data = &of_rcar_gen1_compatible, },
  88        { .compatible = "renesas,rcar-gen2-sdhi", .data = &of_rcar_gen2_compatible, },
  89        { .compatible = "renesas,sdhi-shmobile" },
  90        {},
  91};
  92MODULE_DEVICE_TABLE(of, renesas_sdhi_sys_dmac_of_match);
  93
  94static void renesas_sdhi_sys_dmac_enable_dma(struct tmio_mmc_host *host,
  95                                             bool enable)
  96{
  97        struct renesas_sdhi *priv = host_to_priv(host);
  98
  99        if (!host->chan_tx || !host->chan_rx)
 100                return;
 101
 102        if (priv->dma_priv.enable)
 103                priv->dma_priv.enable(host, enable);
 104}
 105
 106static void renesas_sdhi_sys_dmac_abort_dma(struct tmio_mmc_host *host)
 107{
 108        renesas_sdhi_sys_dmac_enable_dma(host, false);
 109
 110        if (host->chan_rx)
 111                dmaengine_terminate_all(host->chan_rx);
 112        if (host->chan_tx)
 113                dmaengine_terminate_all(host->chan_tx);
 114
 115        renesas_sdhi_sys_dmac_enable_dma(host, true);
 116}
 117
 118static void renesas_sdhi_sys_dmac_dataend_dma(struct tmio_mmc_host *host)
 119{
 120        struct renesas_sdhi *priv = host_to_priv(host);
 121
 122        complete(&priv->dma_priv.dma_dataend);
 123}
 124
 125static void renesas_sdhi_sys_dmac_dma_callback(void *arg)
 126{
 127        struct tmio_mmc_host *host = arg;
 128        struct renesas_sdhi *priv = host_to_priv(host);
 129
 130        spin_lock_irq(&host->lock);
 131
 132        if (!host->data)
 133                goto out;
 134
 135        if (host->data->flags & MMC_DATA_READ)
 136                dma_unmap_sg(host->chan_rx->device->dev,
 137                             host->sg_ptr, host->sg_len,
 138                             DMA_FROM_DEVICE);
 139        else
 140                dma_unmap_sg(host->chan_tx->device->dev,
 141                             host->sg_ptr, host->sg_len,
 142                             DMA_TO_DEVICE);
 143
 144        spin_unlock_irq(&host->lock);
 145
 146        wait_for_completion(&priv->dma_priv.dma_dataend);
 147
 148        spin_lock_irq(&host->lock);
 149        tmio_mmc_do_data_irq(host);
 150out:
 151        spin_unlock_irq(&host->lock);
 152}
 153
 154static void renesas_sdhi_sys_dmac_start_dma_rx(struct tmio_mmc_host *host)
 155{
 156        struct renesas_sdhi *priv = host_to_priv(host);
 157        struct scatterlist *sg = host->sg_ptr, *sg_tmp;
 158        struct dma_async_tx_descriptor *desc = NULL;
 159        struct dma_chan *chan = host->chan_rx;
 160        dma_cookie_t cookie;
 161        int ret, i;
 162        bool aligned = true, multiple = true;
 163        unsigned int align = (1 << host->pdata->alignment_shift) - 1;
 164
 165        for_each_sg(sg, sg_tmp, host->sg_len, i) {
 166                if (sg_tmp->offset & align)
 167                        aligned = false;
 168                if (sg_tmp->length & align) {
 169                        multiple = false;
 170                        break;
 171                }
 172        }
 173
 174        if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_SIZE ||
 175                          (align & PAGE_MASK))) || !multiple) {
 176                ret = -EINVAL;
 177                goto pio;
 178        }
 179
 180        if (sg->length < TMIO_MMC_MIN_DMA_LEN)
 181                return;
 182
 183        /* The only sg element can be unaligned, use our bounce buffer then */
 184        if (!aligned) {
 185                sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
 186                host->sg_ptr = &host->bounce_sg;
 187                sg = host->sg_ptr;
 188        }
 189
 190        ret = dma_map_sg(chan->device->dev, sg, host->sg_len, DMA_FROM_DEVICE);
 191        if (ret > 0)
 192                desc = dmaengine_prep_slave_sg(chan, sg, ret, DMA_DEV_TO_MEM,
 193                                               DMA_CTRL_ACK);
 194
 195        if (desc) {
 196                reinit_completion(&priv->dma_priv.dma_dataend);
 197                desc->callback = renesas_sdhi_sys_dmac_dma_callback;
 198                desc->callback_param = host;
 199
 200                cookie = dmaengine_submit(desc);
 201                if (cookie < 0) {
 202                        desc = NULL;
 203                        ret = cookie;
 204                }
 205                host->dma_on = true;
 206        }
 207pio:
 208        if (!desc) {
 209                /* DMA failed, fall back to PIO */
 210                renesas_sdhi_sys_dmac_enable_dma(host, false);
 211                if (ret >= 0)
 212                        ret = -EIO;
 213                host->chan_rx = NULL;
 214                dma_release_channel(chan);
 215                /* Free the Tx channel too */
 216                chan = host->chan_tx;
 217                if (chan) {
 218                        host->chan_tx = NULL;
 219                        dma_release_channel(chan);
 220                }
 221                dev_warn(&host->pdev->dev,
 222                         "DMA failed: %d, falling back to PIO\n", ret);
 223        }
 224}
 225
 226static void renesas_sdhi_sys_dmac_start_dma_tx(struct tmio_mmc_host *host)
 227{
 228        struct renesas_sdhi *priv = host_to_priv(host);
 229        struct scatterlist *sg = host->sg_ptr, *sg_tmp;
 230        struct dma_async_tx_descriptor *desc = NULL;
 231        struct dma_chan *chan = host->chan_tx;
 232        dma_cookie_t cookie;
 233        int ret, i;
 234        bool aligned = true, multiple = true;
 235        unsigned int align = (1 << host->pdata->alignment_shift) - 1;
 236
 237        for_each_sg(sg, sg_tmp, host->sg_len, i) {
 238                if (sg_tmp->offset & align)
 239                        aligned = false;
 240                if (sg_tmp->length & align) {
 241                        multiple = false;
 242                        break;
 243                }
 244        }
 245
 246        if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_SIZE ||
 247                          (align & PAGE_MASK))) || !multiple) {
 248                ret = -EINVAL;
 249                goto pio;
 250        }
 251
 252        if (sg->length < TMIO_MMC_MIN_DMA_LEN)
 253                return;
 254
 255        /* The only sg element can be unaligned, use our bounce buffer then */
 256        if (!aligned) {
 257                unsigned long flags;
 258                void *sg_vaddr = tmio_mmc_kmap_atomic(sg, &flags);
 259
 260                sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
 261                memcpy(host->bounce_buf, sg_vaddr, host->bounce_sg.length);
 262                tmio_mmc_kunmap_atomic(sg, &flags, sg_vaddr);
 263                host->sg_ptr = &host->bounce_sg;
 264                sg = host->sg_ptr;
 265        }
 266
 267        ret = dma_map_sg(chan->device->dev, sg, host->sg_len, DMA_TO_DEVICE);
 268        if (ret > 0)
 269                desc = dmaengine_prep_slave_sg(chan, sg, ret, DMA_MEM_TO_DEV,
 270                                               DMA_CTRL_ACK);
 271
 272        if (desc) {
 273                reinit_completion(&priv->dma_priv.dma_dataend);
 274                desc->callback = renesas_sdhi_sys_dmac_dma_callback;
 275                desc->callback_param = host;
 276
 277                cookie = dmaengine_submit(desc);
 278                if (cookie < 0) {
 279                        desc = NULL;
 280                        ret = cookie;
 281                }
 282                host->dma_on = true;
 283        }
 284pio:
 285        if (!desc) {
 286                /* DMA failed, fall back to PIO */
 287                renesas_sdhi_sys_dmac_enable_dma(host, false);
 288                if (ret >= 0)
 289                        ret = -EIO;
 290                host->chan_tx = NULL;
 291                dma_release_channel(chan);
 292                /* Free the Rx channel too */
 293                chan = host->chan_rx;
 294                if (chan) {
 295                        host->chan_rx = NULL;
 296                        dma_release_channel(chan);
 297                }
 298                dev_warn(&host->pdev->dev,
 299                         "DMA failed: %d, falling back to PIO\n", ret);
 300        }
 301}
 302
 303static void renesas_sdhi_sys_dmac_start_dma(struct tmio_mmc_host *host,
 304                                            struct mmc_data *data)
 305{
 306        if (data->flags & MMC_DATA_READ) {
 307                if (host->chan_rx)
 308                        renesas_sdhi_sys_dmac_start_dma_rx(host);
 309        } else {
 310                if (host->chan_tx)
 311                        renesas_sdhi_sys_dmac_start_dma_tx(host);
 312        }
 313}
 314
 315static void renesas_sdhi_sys_dmac_issue_tasklet_fn(unsigned long priv)
 316{
 317        struct tmio_mmc_host *host = (struct tmio_mmc_host *)priv;
 318        struct dma_chan *chan = NULL;
 319
 320        spin_lock_irq(&host->lock);
 321
 322        if (host->data) {
 323                if (host->data->flags & MMC_DATA_READ)
 324                        chan = host->chan_rx;
 325                else
 326                        chan = host->chan_tx;
 327        }
 328
 329        spin_unlock_irq(&host->lock);
 330
 331        tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND);
 332
 333        if (chan)
 334                dma_async_issue_pending(chan);
 335}
 336
 337static void renesas_sdhi_sys_dmac_request_dma(struct tmio_mmc_host *host,
 338                                              struct tmio_mmc_data *pdata)
 339{
 340        struct renesas_sdhi *priv = host_to_priv(host);
 341
 342        /* We can only either use DMA for both Tx and Rx or not use it at all */
 343        if (!host->pdev->dev.of_node &&
 344            (!pdata->chan_priv_tx || !pdata->chan_priv_rx))
 345                return;
 346
 347        if (!host->chan_tx && !host->chan_rx) {
 348                struct resource *res = platform_get_resource(host->pdev,
 349                                                             IORESOURCE_MEM, 0);
 350                struct dma_slave_config cfg = {};
 351                dma_cap_mask_t mask;
 352                int ret;
 353
 354                if (!res)
 355                        return;
 356
 357                dma_cap_zero(mask);
 358                dma_cap_set(DMA_SLAVE, mask);
 359
 360                host->chan_tx = dma_request_slave_channel_compat(mask,
 361                                        priv->dma_priv.filter, pdata->chan_priv_tx,
 362                                        &host->pdev->dev, "tx");
 363                dev_dbg(&host->pdev->dev, "%s: TX: got channel %p\n", __func__,
 364                        host->chan_tx);
 365
 366                if (!host->chan_tx)
 367                        return;
 368
 369                cfg.direction = DMA_MEM_TO_DEV;
 370                cfg.dst_addr = res->start +
 371                        (CTL_SD_DATA_PORT << host->bus_shift);
 372                cfg.dst_addr_width = priv->dma_priv.dma_buswidth;
 373                if (!cfg.dst_addr_width)
 374                        cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 375                cfg.src_addr = 0;
 376                ret = dmaengine_slave_config(host->chan_tx, &cfg);
 377                if (ret < 0)
 378                        goto ecfgtx;
 379
 380                host->chan_rx = dma_request_slave_channel_compat(mask,
 381                                        priv->dma_priv.filter, pdata->chan_priv_rx,
 382                                        &host->pdev->dev, "rx");
 383                dev_dbg(&host->pdev->dev, "%s: RX: got channel %p\n", __func__,
 384                        host->chan_rx);
 385
 386                if (!host->chan_rx)
 387                        goto ereqrx;
 388
 389                cfg.direction = DMA_DEV_TO_MEM;
 390                cfg.src_addr = cfg.dst_addr + host->pdata->dma_rx_offset;
 391                cfg.src_addr_width = priv->dma_priv.dma_buswidth;
 392                if (!cfg.src_addr_width)
 393                        cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 394                cfg.dst_addr = 0;
 395                ret = dmaengine_slave_config(host->chan_rx, &cfg);
 396                if (ret < 0)
 397                        goto ecfgrx;
 398
 399                host->bounce_buf = (u8 *)__get_free_page(GFP_KERNEL | GFP_DMA);
 400                if (!host->bounce_buf)
 401                        goto ebouncebuf;
 402
 403                init_completion(&priv->dma_priv.dma_dataend);
 404                tasklet_init(&host->dma_issue,
 405                             renesas_sdhi_sys_dmac_issue_tasklet_fn,
 406                             (unsigned long)host);
 407        }
 408
 409        renesas_sdhi_sys_dmac_enable_dma(host, true);
 410
 411        return;
 412
 413ebouncebuf:
 414ecfgrx:
 415        dma_release_channel(host->chan_rx);
 416        host->chan_rx = NULL;
 417ereqrx:
 418ecfgtx:
 419        dma_release_channel(host->chan_tx);
 420        host->chan_tx = NULL;
 421}
 422
 423static void renesas_sdhi_sys_dmac_release_dma(struct tmio_mmc_host *host)
 424{
 425        if (host->chan_tx) {
 426                struct dma_chan *chan = host->chan_tx;
 427
 428                host->chan_tx = NULL;
 429                dma_release_channel(chan);
 430        }
 431        if (host->chan_rx) {
 432                struct dma_chan *chan = host->chan_rx;
 433
 434                host->chan_rx = NULL;
 435                dma_release_channel(chan);
 436        }
 437        if (host->bounce_buf) {
 438                free_pages((unsigned long)host->bounce_buf, 0);
 439                host->bounce_buf = NULL;
 440        }
 441}
 442
 443static const struct tmio_mmc_dma_ops renesas_sdhi_sys_dmac_dma_ops = {
 444        .start = renesas_sdhi_sys_dmac_start_dma,
 445        .enable = renesas_sdhi_sys_dmac_enable_dma,
 446        .request = renesas_sdhi_sys_dmac_request_dma,
 447        .release = renesas_sdhi_sys_dmac_release_dma,
 448        .abort = renesas_sdhi_sys_dmac_abort_dma,
 449        .dataend = renesas_sdhi_sys_dmac_dataend_dma,
 450};
 451
 452static int renesas_sdhi_sys_dmac_probe(struct platform_device *pdev)
 453{
 454        return renesas_sdhi_probe(pdev, &renesas_sdhi_sys_dmac_dma_ops);
 455}
 456
 457static const struct dev_pm_ops renesas_sdhi_sys_dmac_dev_pm_ops = {
 458        SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
 459                                pm_runtime_force_resume)
 460        SET_RUNTIME_PM_OPS(tmio_mmc_host_runtime_suspend,
 461                           tmio_mmc_host_runtime_resume,
 462                           NULL)
 463};
 464
 465static struct platform_driver renesas_sys_dmac_sdhi_driver = {
 466        .driver         = {
 467                .name   = "sh_mobile_sdhi",
 468                .probe_type = PROBE_PREFER_ASYNCHRONOUS,
 469                .pm     = &renesas_sdhi_sys_dmac_dev_pm_ops,
 470                .of_match_table = renesas_sdhi_sys_dmac_of_match,
 471        },
 472        .probe          = renesas_sdhi_sys_dmac_probe,
 473        .remove         = renesas_sdhi_remove,
 474};
 475
 476module_platform_driver(renesas_sys_dmac_sdhi_driver);
 477
 478MODULE_DESCRIPTION("Renesas SDHI driver");
 479MODULE_AUTHOR("Magnus Damm");
 480MODULE_LICENSE("GPL v2");
 481MODULE_ALIAS("platform:sh_mobile_sdhi");
 482