diff options
Diffstat (limited to '')
-rw-r--r-- | drivers/mmc/host/sdhci-of-sparx5.c | 270 |
1 files changed, 270 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-of-sparx5.c b/drivers/mmc/host/sdhci-of-sparx5.c new file mode 100644 index 000000000..28e4ee69e --- /dev/null +++ b/drivers/mmc/host/sdhci-of-sparx5.c @@ -0,0 +1,270 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * drivers/mmc/host/sdhci-of-sparx5.c + * + * MCHP Sparx5 SoC Secure Digital Host Controller Interface. + * + * Copyright (c) 2019 Microchip Inc. + * + * Author: Lars Povlsen <lars.povlsen@microchip.com> + */ + +#include <linux/sizes.h> +#include <linux/delay.h> +#include <linux/module.h> +#include <linux/regmap.h> +#include <linux/of_device.h> +#include <linux/mfd/syscon.h> +#include <linux/dma-mapping.h> + +#include "sdhci-pltfm.h" + +#define CPU_REGS_GENERAL_CTRL (0x22 * 4) +#define MSHC_DLY_CC_MASK GENMASK(16, 13) +#define MSHC_DLY_CC_SHIFT 13 +#define MSHC_DLY_CC_MAX 15 + +#define CPU_REGS_PROC_CTRL (0x2C * 4) +#define ACP_CACHE_FORCE_ENA BIT(4) +#define ACP_AWCACHE BIT(3) +#define ACP_ARCACHE BIT(2) +#define ACP_CACHE_MASK (ACP_CACHE_FORCE_ENA|ACP_AWCACHE|ACP_ARCACHE) + +#define MSHC2_VERSION 0x500 /* Off 0x140, reg 0x0 */ +#define MSHC2_TYPE 0x504 /* Off 0x140, reg 0x1 */ +#define MSHC2_EMMC_CTRL 0x52c /* Off 0x140, reg 0xB */ +#define MSHC2_EMMC_CTRL_EMMC_RST_N BIT(2) +#define MSHC2_EMMC_CTRL_IS_EMMC BIT(0) + +struct sdhci_sparx5_data { + struct sdhci_host *host; + struct regmap *cpu_ctrl; + int delay_clock; +}; + +#define BOUNDARY_OK(addr, len) \ + ((addr | (SZ_128M - 1)) == ((addr + len - 1) | (SZ_128M - 1))) + +/* + * If DMA addr spans 128MB boundary, we split the DMA transfer into two + * so that each DMA transfer doesn't exceed the boundary. + */ +static void sdhci_sparx5_adma_write_desc(struct sdhci_host *host, void **desc, + dma_addr_t addr, int len, + unsigned int cmd) +{ + int tmplen, offset; + + if (likely(!len || BOUNDARY_OK(addr, len))) { + sdhci_adma_write_desc(host, desc, addr, len, cmd); + return; + } + + pr_debug("%s: write_desc: splitting dma len %d, offset %pad\n", + mmc_hostname(host->mmc), len, &addr); + + offset = addr & (SZ_128M - 1); + tmplen = SZ_128M - offset; + sdhci_adma_write_desc(host, desc, addr, tmplen, cmd); + + addr += tmplen; + len -= tmplen; + sdhci_adma_write_desc(host, desc, addr, len, cmd); +} + +static void sparx5_set_cacheable(struct sdhci_host *host, u32 value) +{ + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); + struct sdhci_sparx5_data *sdhci_sparx5 = sdhci_pltfm_priv(pltfm_host); + + pr_debug("%s: Set Cacheable = 0x%x\n", mmc_hostname(host->mmc), value); + + /* Update ACP caching attributes in HW */ + regmap_update_bits(sdhci_sparx5->cpu_ctrl, + CPU_REGS_PROC_CTRL, ACP_CACHE_MASK, value); +} + +static void sparx5_set_delay(struct sdhci_host *host, u8 value) +{ + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); + struct sdhci_sparx5_data *sdhci_sparx5 = sdhci_pltfm_priv(pltfm_host); + + pr_debug("%s: Set DLY_CC = %u\n", mmc_hostname(host->mmc), value); + + /* Update DLY_CC in HW */ + regmap_update_bits(sdhci_sparx5->cpu_ctrl, + CPU_REGS_GENERAL_CTRL, + MSHC_DLY_CC_MASK, + (value << MSHC_DLY_CC_SHIFT)); +} + +static void sdhci_sparx5_set_emmc(struct sdhci_host *host) +{ + if (!mmc_card_is_removable(host->mmc)) { + u8 value; + + value = sdhci_readb(host, MSHC2_EMMC_CTRL); + if (!(value & MSHC2_EMMC_CTRL_IS_EMMC)) { + value |= MSHC2_EMMC_CTRL_IS_EMMC; + pr_debug("%s: Set EMMC_CTRL: 0x%08x\n", + mmc_hostname(host->mmc), value); + sdhci_writeb(host, value, MSHC2_EMMC_CTRL); + } + } +} + +static void sdhci_sparx5_reset_emmc(struct sdhci_host *host) +{ + u8 value; + + pr_debug("%s: Toggle EMMC_CTRL.EMMC_RST_N\n", mmc_hostname(host->mmc)); + value = sdhci_readb(host, MSHC2_EMMC_CTRL) & + ~MSHC2_EMMC_CTRL_EMMC_RST_N; + sdhci_writeb(host, value, MSHC2_EMMC_CTRL); + /* For eMMC, minimum is 1us but give it 10us for good measure */ + usleep_range(10, 20); + sdhci_writeb(host, value | MSHC2_EMMC_CTRL_EMMC_RST_N, + MSHC2_EMMC_CTRL); + /* For eMMC, minimum is 200us but give it 300us for good measure */ + usleep_range(300, 400); +} + +static void sdhci_sparx5_reset(struct sdhci_host *host, u8 mask) +{ + pr_debug("%s: *** RESET: mask %d\n", mmc_hostname(host->mmc), mask); + + sdhci_reset(host, mask); + + /* Be sure CARD_IS_EMMC stays set */ + sdhci_sparx5_set_emmc(host); +} + +static const struct sdhci_ops sdhci_sparx5_ops = { + .set_clock = sdhci_set_clock, + .set_bus_width = sdhci_set_bus_width, + .set_uhs_signaling = sdhci_set_uhs_signaling, + .get_max_clock = sdhci_pltfm_clk_get_max_clock, + .reset = sdhci_sparx5_reset, + .adma_write_desc = sdhci_sparx5_adma_write_desc, +}; + +static const struct sdhci_pltfm_data sdhci_sparx5_pdata = { + .quirks = 0, + .quirks2 = SDHCI_QUIRK2_HOST_NO_CMD23 | /* Controller issue */ + SDHCI_QUIRK2_NO_1_8_V, /* No sdr104, ddr50, etc */ + .ops = &sdhci_sparx5_ops, +}; + +static int sdhci_sparx5_probe(struct platform_device *pdev) +{ + int ret; + const char *syscon = "microchip,sparx5-cpu-syscon"; + struct sdhci_host *host; + struct sdhci_pltfm_host *pltfm_host; + struct sdhci_sparx5_data *sdhci_sparx5; + struct device_node *np = pdev->dev.of_node; + u32 value; + u32 extra; + + host = sdhci_pltfm_init(pdev, &sdhci_sparx5_pdata, + sizeof(*sdhci_sparx5)); + + if (IS_ERR(host)) + return PTR_ERR(host); + + /* + * extra adma table cnt for cross 128M boundary handling. + */ + extra = DIV_ROUND_UP_ULL(dma_get_required_mask(&pdev->dev), SZ_128M); + if (extra > SDHCI_MAX_SEGS) + extra = SDHCI_MAX_SEGS; + host->adma_table_cnt += extra; + + pltfm_host = sdhci_priv(host); + sdhci_sparx5 = sdhci_pltfm_priv(pltfm_host); + sdhci_sparx5->host = host; + + pltfm_host->clk = devm_clk_get(&pdev->dev, "core"); + if (IS_ERR(pltfm_host->clk)) { + ret = PTR_ERR(pltfm_host->clk); + dev_err(&pdev->dev, "failed to get core clk: %d\n", ret); + goto free_pltfm; + } + ret = clk_prepare_enable(pltfm_host->clk); + if (ret) + goto free_pltfm; + + if (!of_property_read_u32(np, "microchip,clock-delay", &value) && + (value > 0 && value <= MSHC_DLY_CC_MAX)) + sdhci_sparx5->delay_clock = value; + + sdhci_get_of_property(pdev); + + ret = mmc_of_parse(host->mmc); + if (ret) + goto err_clk; + + sdhci_sparx5->cpu_ctrl = syscon_regmap_lookup_by_compatible(syscon); + if (IS_ERR(sdhci_sparx5->cpu_ctrl)) { + dev_err(&pdev->dev, "No CPU syscon regmap !\n"); + ret = PTR_ERR(sdhci_sparx5->cpu_ctrl); + goto err_clk; + } + + if (sdhci_sparx5->delay_clock >= 0) + sparx5_set_delay(host, sdhci_sparx5->delay_clock); + + if (!mmc_card_is_removable(host->mmc)) { + /* Do a HW reset of eMMC card */ + sdhci_sparx5_reset_emmc(host); + /* Update EMMC_CTRL */ + sdhci_sparx5_set_emmc(host); + /* If eMMC, disable SD and SDIO */ + host->mmc->caps2 |= (MMC_CAP2_NO_SDIO|MMC_CAP2_NO_SD); + } + + ret = sdhci_add_host(host); + if (ret) + goto err_clk; + + /* Set AXI bus master to use un-cached access (for DMA) */ + if (host->flags & (SDHCI_USE_SDMA | SDHCI_USE_ADMA) && + IS_ENABLED(CONFIG_DMA_DECLARE_COHERENT)) + sparx5_set_cacheable(host, ACP_CACHE_FORCE_ENA); + + pr_debug("%s: SDHC version: 0x%08x\n", + mmc_hostname(host->mmc), sdhci_readl(host, MSHC2_VERSION)); + pr_debug("%s: SDHC type: 0x%08x\n", + mmc_hostname(host->mmc), sdhci_readl(host, MSHC2_TYPE)); + + return ret; + +err_clk: + clk_disable_unprepare(pltfm_host->clk); +free_pltfm: + sdhci_pltfm_free(pdev); + return ret; +} + +static const struct of_device_id sdhci_sparx5_of_match[] = { + { .compatible = "microchip,dw-sparx5-sdhci" }, + { } +}; +MODULE_DEVICE_TABLE(of, sdhci_sparx5_of_match); + +static struct platform_driver sdhci_sparx5_driver = { + .driver = { + .name = "sdhci-sparx5", + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + .of_match_table = sdhci_sparx5_of_match, + .pm = &sdhci_pltfm_pmops, + }, + .probe = sdhci_sparx5_probe, + .remove = sdhci_pltfm_unregister, +}; + +module_platform_driver(sdhci_sparx5_driver); + +MODULE_DESCRIPTION("Sparx5 SDHCI OF driver"); +MODULE_AUTHOR("Lars Povlsen <lars.povlsen@microchip.com>"); +MODULE_LICENSE("GPL v2"); |