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path: root/drivers/mmc/host/sdhci-of-at91.c
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Diffstat (limited to 'drivers/mmc/host/sdhci-of-at91.c')
-rw-r--r--drivers/mmc/host/sdhci-of-at91.c483
1 files changed, 483 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..cd0134580
--- /dev/null
+++ b/drivers/mmc/host/sdhci-of-at91.c
@@ -0,0 +1,483 @@
+// 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 sdhci_at91_soc_data *soc_data;
+ struct sdhci_host *host;
+ struct sdhci_pltfm_host *pltfm_host;
+ struct sdhci_at91_priv *priv;
+ int ret;
+
+ soc_data = of_device_get_match_data(&pdev->dev);
+ if (!soc_data)
+ return -EINVAL;
+
+ 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");