diff options
Diffstat (limited to 'drivers/mmc/host/renesas_sdhi_internal_dmac.c')
| -rw-r--r-- | drivers/mmc/host/renesas_sdhi_internal_dmac.c | 368 |
1 files changed, 368 insertions, 0 deletions
diff --git a/drivers/mmc/host/renesas_sdhi_internal_dmac.c b/drivers/mmc/host/renesas_sdhi_internal_dmac.c new file mode 100644 index 000000000..f3e76d6b3 --- /dev/null +++ b/drivers/mmc/host/renesas_sdhi_internal_dmac.c @@ -0,0 +1,368 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DMA support for Internal DMAC with SDHI SD/SDIO controller + * + * Copyright (C) 2016-19 Renesas Electronics Corporation + * Copyright (C) 2016-17 Horms Solutions, Simon Horman + * Copyright (C) 2018-19 Sang Engineering, Wolfram Sang + */ + +#include <linux/bitops.h> +#include <linux/device.h> +#include <linux/dma-mapping.h> +#include <linux/io-64-nonatomic-hi-lo.h> +#include <linux/mfd/tmio.h> +#include <linux/mmc/host.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/pagemap.h> +#include <linux/scatterlist.h> +#include <linux/sys_soc.h> + +#include "renesas_sdhi.h" +#include "tmio_mmc.h" + +#define DM_CM_DTRAN_MODE 0x820 +#define DM_CM_DTRAN_CTRL 0x828 +#define DM_CM_RST 0x830 +#define DM_CM_INFO1 0x840 +#define DM_CM_INFO1_MASK 0x848 +#define DM_CM_INFO2 0x850 +#define DM_CM_INFO2_MASK 0x858 +#define DM_DTRAN_ADDR 0x880 + +/* DM_CM_DTRAN_MODE */ +#define DTRAN_MODE_CH_NUM_CH0 0 /* "downstream" = for write commands */ +#define DTRAN_MODE_CH_NUM_CH1 BIT(16) /* "upstream" = for read commands */ +#define DTRAN_MODE_BUS_WIDTH (BIT(5) | BIT(4)) +#define DTRAN_MODE_ADDR_MODE BIT(0) /* 1 = Increment address, 0 = Fixed */ + +/* DM_CM_DTRAN_CTRL */ +#define DTRAN_CTRL_DM_START BIT(0) + +/* DM_CM_RST */ +#define RST_DTRANRST1 BIT(9) +#define RST_DTRANRST0 BIT(8) +#define RST_RESERVED_BITS GENMASK_ULL(31, 0) + +/* DM_CM_INFO1 and DM_CM_INFO1_MASK */ +#define INFO1_CLEAR 0 +#define INFO1_MASK_CLEAR GENMASK_ULL(31, 0) +#define INFO1_DTRANEND1 BIT(17) +#define INFO1_DTRANEND0 BIT(16) + +/* DM_CM_INFO2 and DM_CM_INFO2_MASK */ +#define INFO2_MASK_CLEAR GENMASK_ULL(31, 0) +#define INFO2_DTRANERR1 BIT(17) +#define INFO2_DTRANERR0 BIT(16) + +/* + * Specification of this driver: + * - host->chan_{rx,tx} will be used as a flag of enabling/disabling the dma + * - Since this SDHI DMAC register set has 16 but 32-bit width, we + * need a custom accessor. + */ + +static unsigned long global_flags; +/* + * Workaround for avoiding to use RX DMAC by multiple channels. + * On R-Car H3 ES1.* and M3-W ES1.0, when multiple SDHI channels use + * RX DMAC simultaneously, sometimes hundreds of bytes data are not + * stored into the system memory even if the DMAC interrupt happened. + * So, this driver then uses one RX DMAC channel only. + */ +#define SDHI_INTERNAL_DMAC_ONE_RX_ONLY 0 +#define SDHI_INTERNAL_DMAC_RX_IN_USE 1 + +/* RZ/A2 does not have the ADRR_MODE bit */ +#define SDHI_INTERNAL_DMAC_ADDR_MODE_FIXED_ONLY 2 + +/* Definitions for sampling clocks */ +static struct renesas_sdhi_scc rcar_gen3_scc_taps[] = { + { + .clk_rate = 0, + .tap = 0x00000300, + .tap_hs400_4tap = 0x00000100, + }, +}; + +static const struct renesas_sdhi_of_data of_rza2_compatible = { + .tmio_flags = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_CLK_ACTUAL | + TMIO_MMC_HAVE_CBSY, + .tmio_ocr_mask = MMC_VDD_32_33, + .capabilities = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ | + MMC_CAP_CMD23, + .bus_shift = 2, + .scc_offset = 0 - 0x1000, + .taps = rcar_gen3_scc_taps, + .taps_num = ARRAY_SIZE(rcar_gen3_scc_taps), + /* DMAC can handle 32bit blk count but only 1 segment */ + .max_blk_count = UINT_MAX / TMIO_MAX_BLK_SIZE, + .max_segs = 1, +}; + +static const struct renesas_sdhi_of_data of_rcar_gen3_compatible = { + .tmio_flags = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_CLK_ACTUAL | + TMIO_MMC_HAVE_CBSY | TMIO_MMC_MIN_RCAR2, + .capabilities = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ | + MMC_CAP_CMD23, + .capabilities2 = MMC_CAP2_NO_WRITE_PROTECT | MMC_CAP2_MERGE_CAPABLE, + .bus_shift = 2, + .scc_offset = 0x1000, + .taps = rcar_gen3_scc_taps, + .taps_num = ARRAY_SIZE(rcar_gen3_scc_taps), + /* DMAC can handle 32bit blk count but only 1 segment */ + .max_blk_count = UINT_MAX / TMIO_MAX_BLK_SIZE, + .max_segs = 1, +}; + +static const struct of_device_id renesas_sdhi_internal_dmac_of_match[] = { + { .compatible = "renesas,sdhi-r7s9210", .data = &of_rza2_compatible, }, + { .compatible = "renesas,sdhi-mmc-r8a77470", .data = &of_rcar_gen3_compatible, }, + { .compatible = "renesas,sdhi-r8a7795", .data = &of_rcar_gen3_compatible, }, + { .compatible = "renesas,sdhi-r8a7796", .data = &of_rcar_gen3_compatible, }, + { .compatible = "renesas,rcar-gen3-sdhi", .data = &of_rcar_gen3_compatible, }, + {}, +}; +MODULE_DEVICE_TABLE(of, renesas_sdhi_internal_dmac_of_match); + +static void +renesas_sdhi_internal_dmac_dm_write(struct tmio_mmc_host *host, + int addr, u64 val) +{ + writeq(val, host->ctl + addr); +} + +static void +renesas_sdhi_internal_dmac_enable_dma(struct tmio_mmc_host *host, bool enable) +{ + struct renesas_sdhi *priv = host_to_priv(host); + + if (!host->chan_tx || !host->chan_rx) + return; + + if (!enable) + renesas_sdhi_internal_dmac_dm_write(host, DM_CM_INFO1, + INFO1_CLEAR); + + if (priv->dma_priv.enable) + priv->dma_priv.enable(host, enable); +} + +static void +renesas_sdhi_internal_dmac_abort_dma(struct tmio_mmc_host *host) { + u64 val = RST_DTRANRST1 | RST_DTRANRST0; + + renesas_sdhi_internal_dmac_enable_dma(host, false); + + renesas_sdhi_internal_dmac_dm_write(host, DM_CM_RST, + RST_RESERVED_BITS & ~val); + renesas_sdhi_internal_dmac_dm_write(host, DM_CM_RST, + RST_RESERVED_BITS | val); + + clear_bit(SDHI_INTERNAL_DMAC_RX_IN_USE, &global_flags); + + renesas_sdhi_internal_dmac_enable_dma(host, true); +} + +static void +renesas_sdhi_internal_dmac_dataend_dma(struct tmio_mmc_host *host) { + struct renesas_sdhi *priv = host_to_priv(host); + + tasklet_schedule(&priv->dma_priv.dma_complete); +} + +static void +renesas_sdhi_internal_dmac_start_dma(struct tmio_mmc_host *host, + struct mmc_data *data) +{ + struct scatterlist *sg = host->sg_ptr; + u32 dtran_mode = DTRAN_MODE_BUS_WIDTH; + + if (!test_bit(SDHI_INTERNAL_DMAC_ADDR_MODE_FIXED_ONLY, &global_flags)) + dtran_mode |= DTRAN_MODE_ADDR_MODE; + + if (!dma_map_sg(&host->pdev->dev, sg, host->sg_len, + mmc_get_dma_dir(data))) + goto force_pio; + + /* This DMAC cannot handle if buffer is not 128-bytes alignment */ + if (!IS_ALIGNED(sg_dma_address(sg), 128)) + goto force_pio_with_unmap; + + if (data->flags & MMC_DATA_READ) { + dtran_mode |= DTRAN_MODE_CH_NUM_CH1; + if (test_bit(SDHI_INTERNAL_DMAC_ONE_RX_ONLY, &global_flags) && + test_and_set_bit(SDHI_INTERNAL_DMAC_RX_IN_USE, &global_flags)) + goto force_pio_with_unmap; + } else { + dtran_mode |= DTRAN_MODE_CH_NUM_CH0; + } + + renesas_sdhi_internal_dmac_enable_dma(host, true); + + /* set dma parameters */ + renesas_sdhi_internal_dmac_dm_write(host, DM_CM_DTRAN_MODE, + dtran_mode); + renesas_sdhi_internal_dmac_dm_write(host, DM_DTRAN_ADDR, + sg_dma_address(sg)); + + host->dma_on = true; + + return; + +force_pio_with_unmap: + dma_unmap_sg(&host->pdev->dev, sg, host->sg_len, mmc_get_dma_dir(data)); + +force_pio: + renesas_sdhi_internal_dmac_enable_dma(host, false); +} + +static void renesas_sdhi_internal_dmac_issue_tasklet_fn(unsigned long arg) +{ + struct tmio_mmc_host *host = (struct tmio_mmc_host *)arg; + + tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND); + + /* start the DMAC */ + renesas_sdhi_internal_dmac_dm_write(host, DM_CM_DTRAN_CTRL, + DTRAN_CTRL_DM_START); +} + +static bool renesas_sdhi_internal_dmac_complete(struct tmio_mmc_host *host) +{ + enum dma_data_direction dir; + + if (!host->dma_on) + return false; + + if (!host->data) + return false; + + if (host->data->flags & MMC_DATA_READ) + dir = DMA_FROM_DEVICE; + else + dir = DMA_TO_DEVICE; + + renesas_sdhi_internal_dmac_enable_dma(host, false); + dma_unmap_sg(&host->pdev->dev, host->sg_ptr, host->sg_len, dir); + + if (dir == DMA_FROM_DEVICE) + clear_bit(SDHI_INTERNAL_DMAC_RX_IN_USE, &global_flags); + + host->dma_on = false; + + return true; +} + +static void renesas_sdhi_internal_dmac_complete_tasklet_fn(unsigned long arg) +{ + struct tmio_mmc_host *host = (struct tmio_mmc_host *)arg; + + spin_lock_irq(&host->lock); + if (!renesas_sdhi_internal_dmac_complete(host)) + goto out; + + tmio_mmc_do_data_irq(host); +out: + spin_unlock_irq(&host->lock); +} + +static void renesas_sdhi_internal_dmac_end_dma(struct tmio_mmc_host *host) +{ + if (host->data) + renesas_sdhi_internal_dmac_complete(host); +} + +static void +renesas_sdhi_internal_dmac_request_dma(struct tmio_mmc_host *host, + struct tmio_mmc_data *pdata) +{ + struct renesas_sdhi *priv = host_to_priv(host); + + /* Disable DMAC interrupts, we don't use them */ + renesas_sdhi_internal_dmac_dm_write(host, DM_CM_INFO1_MASK, + INFO1_MASK_CLEAR); + renesas_sdhi_internal_dmac_dm_write(host, DM_CM_INFO2_MASK, + INFO2_MASK_CLEAR); + + /* Each value is set to non-zero to assume "enabling" each DMA */ + host->chan_rx = host->chan_tx = (void *)0xdeadbeaf; + + tasklet_init(&priv->dma_priv.dma_complete, + renesas_sdhi_internal_dmac_complete_tasklet_fn, + (unsigned long)host); + tasklet_init(&host->dma_issue, + renesas_sdhi_internal_dmac_issue_tasklet_fn, + (unsigned long)host); +} + +static void +renesas_sdhi_internal_dmac_release_dma(struct tmio_mmc_host *host) +{ + /* Each value is set to zero to assume "disabling" each DMA */ + host->chan_rx = host->chan_tx = NULL; +} + +static const struct tmio_mmc_dma_ops renesas_sdhi_internal_dmac_dma_ops = { + .start = renesas_sdhi_internal_dmac_start_dma, + .enable = renesas_sdhi_internal_dmac_enable_dma, + .request = renesas_sdhi_internal_dmac_request_dma, + .release = renesas_sdhi_internal_dmac_release_dma, + .abort = renesas_sdhi_internal_dmac_abort_dma, + .dataend = renesas_sdhi_internal_dmac_dataend_dma, + .end = renesas_sdhi_internal_dmac_end_dma, +}; + +/* + * Whitelist of specific R-Car Gen3 SoC ES versions to use this DMAC + * implementation as others may use a different implementation. + */ +static const struct soc_device_attribute soc_dma_quirks[] = { + { .soc_id = "r7s9210", + .data = (void *)BIT(SDHI_INTERNAL_DMAC_ADDR_MODE_FIXED_ONLY) }, + { .soc_id = "r8a7795", .revision = "ES1.*", + .data = (void *)BIT(SDHI_INTERNAL_DMAC_ONE_RX_ONLY) }, + { .soc_id = "r8a7796", .revision = "ES1.0", + .data = (void *)BIT(SDHI_INTERNAL_DMAC_ONE_RX_ONLY) }, + { /* sentinel */ } +}; + +static int renesas_sdhi_internal_dmac_probe(struct platform_device *pdev) +{ + const struct soc_device_attribute *soc = soc_device_match(soc_dma_quirks); + struct device *dev = &pdev->dev; + + if (soc) + global_flags |= (unsigned long)soc->data; + + /* value is max of SD_SECCNT. Confirmed by HW engineers */ + dma_set_max_seg_size(dev, 0xffffffff); + + return renesas_sdhi_probe(pdev, &renesas_sdhi_internal_dmac_dma_ops); +} + +static const struct dev_pm_ops renesas_sdhi_internal_dmac_dev_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, + pm_runtime_force_resume) + SET_RUNTIME_PM_OPS(tmio_mmc_host_runtime_suspend, + tmio_mmc_host_runtime_resume, + NULL) +}; + +static struct platform_driver renesas_internal_dmac_sdhi_driver = { + .driver = { + .name = "renesas_sdhi_internal_dmac", + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + .pm = &renesas_sdhi_internal_dmac_dev_pm_ops, + .of_match_table = renesas_sdhi_internal_dmac_of_match, + }, + .probe = renesas_sdhi_internal_dmac_probe, + .remove = renesas_sdhi_remove, +}; + +module_platform_driver(renesas_internal_dmac_sdhi_driver); + +MODULE_DESCRIPTION("Renesas SDHI driver for internal DMAC"); +MODULE_AUTHOR("Yoshihiro Shimoda"); +MODULE_LICENSE("GPL v2"); |