diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/mmc/host/sdhci-of-at91.c | 485 |
1 files changed, 485 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-of-at91.c b/drivers/mmc/host/sdhci-of-at91.c new file mode 100644 index 000000000..0452c312b --- /dev/null +++ b/drivers/mmc/host/sdhci-of-at91.c @@ -0,0 +1,485 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Atmel SDMMC controller driver. + * + * Copyright (C) 2015 Atmel, + * 2015 Ludovic Desroches <ludovic.desroches@atmel.com> + */ + +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/kernel.h> +#include <linux/mmc/host.h> +#include <linux/mmc/slot-gpio.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/pm.h> +#include <linux/pm_runtime.h> + +#include "sdhci-pltfm.h" + +#define SDMMC_MC1R 0x204 +#define SDMMC_MC1R_DDR BIT(3) +#define SDMMC_MC1R_FCD BIT(7) +#define SDMMC_CACR 0x230 +#define SDMMC_CACR_CAPWREN BIT(0) +#define SDMMC_CACR_KEY (0x46 << 8) +#define SDMMC_CALCR 0x240 +#define SDMMC_CALCR_EN BIT(0) +#define SDMMC_CALCR_ALWYSON BIT(4) + +#define SDHCI_AT91_PRESET_COMMON_CONF 0x400 /* drv type B, programmable clock mode */ + +struct sdhci_at91_soc_data { + const struct sdhci_pltfm_data *pdata; + bool baseclk_is_generated_internally; + unsigned int divider_for_baseclk; +}; + +struct sdhci_at91_priv { + const struct sdhci_at91_soc_data *soc_data; + struct clk *hclock; + struct clk *gck; + struct clk *mainck; + bool restore_needed; + bool cal_always_on; +}; + +static void sdhci_at91_set_force_card_detect(struct sdhci_host *host) +{ + u8 mc1r; + + mc1r = readb(host->ioaddr + SDMMC_MC1R); + mc1r |= SDMMC_MC1R_FCD; + writeb(mc1r, host->ioaddr + SDMMC_MC1R); +} + +static void sdhci_at91_set_clock(struct sdhci_host *host, unsigned int clock) +{ + u16 clk; + + host->mmc->actual_clock = 0; + + /* + * There is no requirement to disable the internal clock before + * changing the SD clock configuration. Moreover, disabling the + * internal clock, changing the configuration and re-enabling the + * internal clock causes some bugs. It can prevent to get the internal + * clock stable flag ready and an unexpected switch to the base clock + * when using presets. + */ + clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL); + clk &= SDHCI_CLOCK_INT_EN; + sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL); + + if (clock == 0) + return; + + clk = sdhci_calc_clk(host, clock, &host->mmc->actual_clock); + + clk |= SDHCI_CLOCK_INT_EN; + sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL); + + /* Wait max 20 ms */ + if (read_poll_timeout(sdhci_readw, clk, (clk & SDHCI_CLOCK_INT_STABLE), + 1000, 20000, false, host, SDHCI_CLOCK_CONTROL)) { + pr_err("%s: Internal clock never stabilised.\n", + mmc_hostname(host->mmc)); + return; + } + + clk |= SDHCI_CLOCK_CARD_EN; + sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL); +} + +static void sdhci_at91_set_uhs_signaling(struct sdhci_host *host, + unsigned int timing) +{ + u8 mc1r; + + if (timing == MMC_TIMING_MMC_DDR52) { + mc1r = sdhci_readb(host, SDMMC_MC1R); + mc1r |= SDMMC_MC1R_DDR; + sdhci_writeb(host, mc1r, SDMMC_MC1R); + } + sdhci_set_uhs_signaling(host, timing); +} + +static void sdhci_at91_reset(struct sdhci_host *host, u8 mask) +{ + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); + struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host); + unsigned int tmp; + + sdhci_reset(host, mask); + + if ((host->mmc->caps & MMC_CAP_NONREMOVABLE) + || mmc_gpio_get_cd(host->mmc) >= 0) + sdhci_at91_set_force_card_detect(host); + + if (priv->cal_always_on && (mask & SDHCI_RESET_ALL)) { + u32 calcr = sdhci_readl(host, SDMMC_CALCR); + + sdhci_writel(host, calcr | SDMMC_CALCR_ALWYSON | SDMMC_CALCR_EN, + SDMMC_CALCR); + + if (read_poll_timeout(sdhci_readl, tmp, !(tmp & SDMMC_CALCR_EN), + 10, 20000, false, host, SDMMC_CALCR)) + dev_err(mmc_dev(host->mmc), "Failed to calibrate\n"); + } +} + +static const struct sdhci_ops sdhci_at91_sama5d2_ops = { + .set_clock = sdhci_at91_set_clock, + .set_bus_width = sdhci_set_bus_width, + .reset = sdhci_at91_reset, + .set_uhs_signaling = sdhci_at91_set_uhs_signaling, + .set_power = sdhci_set_power_and_bus_voltage, +}; + +static const struct sdhci_pltfm_data sdhci_sama5d2_pdata = { + .ops = &sdhci_at91_sama5d2_ops, +}; + +static const struct sdhci_at91_soc_data soc_data_sama5d2 = { + .pdata = &sdhci_sama5d2_pdata, + .baseclk_is_generated_internally = false, +}; + +static const struct sdhci_at91_soc_data soc_data_sam9x60 = { + .pdata = &sdhci_sama5d2_pdata, + .baseclk_is_generated_internally = true, + .divider_for_baseclk = 2, +}; + +static const struct of_device_id sdhci_at91_dt_match[] = { + { .compatible = "atmel,sama5d2-sdhci", .data = &soc_data_sama5d2 }, + { .compatible = "microchip,sam9x60-sdhci", .data = &soc_data_sam9x60 }, + {} +}; +MODULE_DEVICE_TABLE(of, sdhci_at91_dt_match); + +static int sdhci_at91_set_clks_presets(struct device *dev) +{ + struct sdhci_host *host = dev_get_drvdata(dev); + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); + struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host); + unsigned int caps0, caps1; + unsigned int clk_base, clk_mul; + unsigned int gck_rate, clk_base_rate; + unsigned int preset_div; + + clk_prepare_enable(priv->hclock); + caps0 = readl(host->ioaddr + SDHCI_CAPABILITIES); + caps1 = readl(host->ioaddr + SDHCI_CAPABILITIES_1); + + gck_rate = clk_get_rate(priv->gck); + if (priv->soc_data->baseclk_is_generated_internally) + clk_base_rate = gck_rate / priv->soc_data->divider_for_baseclk; + else + clk_base_rate = clk_get_rate(priv->mainck); + + clk_base = clk_base_rate / 1000000; + clk_mul = gck_rate / clk_base_rate - 1; + + caps0 &= ~SDHCI_CLOCK_V3_BASE_MASK; + caps0 |= FIELD_PREP(SDHCI_CLOCK_V3_BASE_MASK, clk_base); + caps1 &= ~SDHCI_CLOCK_MUL_MASK; + caps1 |= FIELD_PREP(SDHCI_CLOCK_MUL_MASK, clk_mul); + /* Set capabilities in r/w mode. */ + writel(SDMMC_CACR_KEY | SDMMC_CACR_CAPWREN, host->ioaddr + SDMMC_CACR); + writel(caps0, host->ioaddr + SDHCI_CAPABILITIES); + writel(caps1, host->ioaddr + SDHCI_CAPABILITIES_1); + /* Set capabilities in ro mode. */ + writel(0, host->ioaddr + SDMMC_CACR); + + dev_dbg(dev, "update clk mul to %u as gck rate is %u Hz and clk base is %u Hz\n", + clk_mul, gck_rate, clk_base_rate); + + /* + * We have to set preset values because it depends on the clk_mul + * value. Moreover, SDR104 is supported in a degraded mode since the + * maximum sd clock value is 120 MHz instead of 208 MHz. For that + * reason, we need to use presets to support SDR104. + */ + preset_div = DIV_ROUND_UP(gck_rate, 24000000) - 1; + writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div, + host->ioaddr + SDHCI_PRESET_FOR_SDR12); + preset_div = DIV_ROUND_UP(gck_rate, 50000000) - 1; + writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div, + host->ioaddr + SDHCI_PRESET_FOR_SDR25); + preset_div = DIV_ROUND_UP(gck_rate, 100000000) - 1; + writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div, + host->ioaddr + SDHCI_PRESET_FOR_SDR50); + preset_div = DIV_ROUND_UP(gck_rate, 120000000) - 1; + writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div, + host->ioaddr + SDHCI_PRESET_FOR_SDR104); + preset_div = DIV_ROUND_UP(gck_rate, 50000000) - 1; + writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div, + host->ioaddr + SDHCI_PRESET_FOR_DDR50); + + clk_prepare_enable(priv->mainck); + clk_prepare_enable(priv->gck); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int sdhci_at91_suspend(struct device *dev) +{ + struct sdhci_host *host = dev_get_drvdata(dev); + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); + struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host); + int ret; + + ret = pm_runtime_force_suspend(dev); + + priv->restore_needed = true; + + return ret; +} +#endif /* CONFIG_PM_SLEEP */ + +#ifdef CONFIG_PM +static int sdhci_at91_runtime_suspend(struct device *dev) +{ + struct sdhci_host *host = dev_get_drvdata(dev); + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); + struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host); + int ret; + + ret = sdhci_runtime_suspend_host(host); + + if (host->tuning_mode != SDHCI_TUNING_MODE_3) + mmc_retune_needed(host->mmc); + + clk_disable_unprepare(priv->gck); + clk_disable_unprepare(priv->hclock); + clk_disable_unprepare(priv->mainck); + + return ret; +} + +static int sdhci_at91_runtime_resume(struct device *dev) +{ + struct sdhci_host *host = dev_get_drvdata(dev); + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); + struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host); + int ret; + + if (priv->restore_needed) { + ret = sdhci_at91_set_clks_presets(dev); + if (ret) + return ret; + + priv->restore_needed = false; + goto out; + } + + ret = clk_prepare_enable(priv->mainck); + if (ret) { + dev_err(dev, "can't enable mainck\n"); + return ret; + } + + ret = clk_prepare_enable(priv->hclock); + if (ret) { + dev_err(dev, "can't enable hclock\n"); + return ret; + } + + ret = clk_prepare_enable(priv->gck); + if (ret) { + dev_err(dev, "can't enable gck\n"); + return ret; + } + +out: + return sdhci_runtime_resume_host(host, 0); +} +#endif /* CONFIG_PM */ + +static const struct dev_pm_ops sdhci_at91_dev_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(sdhci_at91_suspend, pm_runtime_force_resume) + SET_RUNTIME_PM_OPS(sdhci_at91_runtime_suspend, + sdhci_at91_runtime_resume, + NULL) +}; + +static int sdhci_at91_probe(struct platform_device *pdev) +{ + const struct of_device_id *match; + const struct sdhci_at91_soc_data *soc_data; + struct sdhci_host *host; + struct sdhci_pltfm_host *pltfm_host; + struct sdhci_at91_priv *priv; + int ret; + + match = of_match_device(sdhci_at91_dt_match, &pdev->dev); + if (!match) + return -EINVAL; + soc_data = match->data; + + host = sdhci_pltfm_init(pdev, soc_data->pdata, sizeof(*priv)); + if (IS_ERR(host)) + return PTR_ERR(host); + + pltfm_host = sdhci_priv(host); + priv = sdhci_pltfm_priv(pltfm_host); + priv->soc_data = soc_data; + + priv->mainck = devm_clk_get(&pdev->dev, "baseclk"); + if (IS_ERR(priv->mainck)) { + if (soc_data->baseclk_is_generated_internally) { + priv->mainck = NULL; + } else { + dev_err(&pdev->dev, "failed to get baseclk\n"); + ret = PTR_ERR(priv->mainck); + goto sdhci_pltfm_free; + } + } + + priv->hclock = devm_clk_get(&pdev->dev, "hclock"); + if (IS_ERR(priv->hclock)) { + dev_err(&pdev->dev, "failed to get hclock\n"); + ret = PTR_ERR(priv->hclock); + goto sdhci_pltfm_free; + } + + priv->gck = devm_clk_get(&pdev->dev, "multclk"); + if (IS_ERR(priv->gck)) { + dev_err(&pdev->dev, "failed to get multclk\n"); + ret = PTR_ERR(priv->gck); + goto sdhci_pltfm_free; + } + + ret = sdhci_at91_set_clks_presets(&pdev->dev); + if (ret) + goto sdhci_pltfm_free; + + priv->restore_needed = false; + + /* + * if SDCAL pin is wrongly connected, we must enable + * the analog calibration cell permanently. + */ + priv->cal_always_on = + device_property_read_bool(&pdev->dev, + "microchip,sdcal-inverted"); + + ret = mmc_of_parse(host->mmc); + if (ret) + goto clocks_disable_unprepare; + + sdhci_get_of_property(pdev); + + pm_runtime_get_noresume(&pdev->dev); + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + pm_runtime_set_autosuspend_delay(&pdev->dev, 50); + pm_runtime_use_autosuspend(&pdev->dev); + + /* HS200 is broken at this moment */ + host->quirks2 |= SDHCI_QUIRK2_BROKEN_HS200; + + ret = sdhci_add_host(host); + if (ret) + goto pm_runtime_disable; + + /* + * When calling sdhci_runtime_suspend_host(), the sdhci layer makes + * the assumption that all the clocks of the controller are disabled. + * It means we can't get irq from it when it is runtime suspended. + * For that reason, it is not planned to wake-up on a card detect irq + * from the controller. + * If we want to use runtime PM and to be able to wake-up on card + * insertion, we have to use a GPIO for the card detection or we can + * use polling. Be aware that using polling will resume/suspend the + * controller between each attempt. + * Disable SDHCI_QUIRK_BROKEN_CARD_DETECTION to be sure nobody tries + * to enable polling via device tree with broken-cd property. + */ + if (mmc_card_is_removable(host->mmc) && + mmc_gpio_get_cd(host->mmc) < 0) { + host->mmc->caps |= MMC_CAP_NEEDS_POLL; + host->quirks &= ~SDHCI_QUIRK_BROKEN_CARD_DETECTION; + } + + /* + * If the device attached to the MMC bus is not removable, it is safer + * to set the Force Card Detect bit. People often don't connect the + * card detect signal and use this pin for another purpose. If the card + * detect pin is not muxed to SDHCI controller, a default value is + * used. This value can be different from a SoC revision to another + * one. Problems come when this default value is not card present. To + * avoid this case, if the device is non removable then the card + * detection procedure using the SDMCC_CD signal is bypassed. + * This bit is reset when a software reset for all command is performed + * so we need to implement our own reset function to set back this bit. + * + * WA: SAMA5D2 doesn't drive CMD if using CD GPIO line. + */ + if ((host->mmc->caps & MMC_CAP_NONREMOVABLE) + || mmc_gpio_get_cd(host->mmc) >= 0) + sdhci_at91_set_force_card_detect(host); + + pm_runtime_put_autosuspend(&pdev->dev); + + return 0; + +pm_runtime_disable: + pm_runtime_disable(&pdev->dev); + pm_runtime_set_suspended(&pdev->dev); + pm_runtime_put_noidle(&pdev->dev); +clocks_disable_unprepare: + clk_disable_unprepare(priv->gck); + clk_disable_unprepare(priv->mainck); + clk_disable_unprepare(priv->hclock); +sdhci_pltfm_free: + sdhci_pltfm_free(pdev); + return ret; +} + +static int sdhci_at91_remove(struct platform_device *pdev) +{ + struct sdhci_host *host = platform_get_drvdata(pdev); + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); + struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host); + struct clk *gck = priv->gck; + struct clk *hclock = priv->hclock; + struct clk *mainck = priv->mainck; + + pm_runtime_get_sync(&pdev->dev); + pm_runtime_disable(&pdev->dev); + pm_runtime_put_noidle(&pdev->dev); + + sdhci_pltfm_unregister(pdev); + + clk_disable_unprepare(gck); + clk_disable_unprepare(hclock); + clk_disable_unprepare(mainck); + + return 0; +} + +static struct platform_driver sdhci_at91_driver = { + .driver = { + .name = "sdhci-at91", + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + .of_match_table = sdhci_at91_dt_match, + .pm = &sdhci_at91_dev_pm_ops, + }, + .probe = sdhci_at91_probe, + .remove = sdhci_at91_remove, +}; + +module_platform_driver(sdhci_at91_driver); + +MODULE_DESCRIPTION("SDHCI driver for at91"); +MODULE_AUTHOR("Ludovic Desroches <ludovic.desroches@atmel.com>"); +MODULE_LICENSE("GPL v2"); |