mmc: sdhci-milbeaut: add Milbeaut SD controller driver

SD Host controller on Milbeaut consists of two controller parts.
One is core controller F_SDH30, this is similar to sdhci-fujitsu
controller.
Another is bridge controller.
This bridge controller is not compatible with sdhci-fujitsu controller.
This is special for Milbeaut series. This has some functions.
For example, reset control, clock enable/select for SDR50/25/12, set
property of SD physical pins, retuning control, set capabilityies.

This bridge controller requires special procedures at reset or clock
enablement or change for further tuning of clock.

Signed-off-by: Takao Orito <orito.takao@socionext.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/Kconfig

@@ -368,6 +368,17 @@ config MMC_SDHCI_F_SDH30
 
 	  If unsure, say N.
 
+config MMC_SDHCI_MILBEAUT
+	tristate "SDHCI support for Socionext Milbeaut Serieas using F_SDH30"
+	depends on MMC_SDHCI_PLTFM
+	depends on OF
+	help
+	  This selects the Secure Digital Host Controller Interface (SDHCI)
+	  Needed by Milbeaut SoC for MMC / SD / SDIO support.
+	  If you have a controller with this interface, say Y or M here.
+
+	  If unsure, say N.
+
 config MMC_SDHCI_IPROC
 	tristate "SDHCI support for the BCM2835 & iProc SD/MMC Controller"
 	depends on ARCH_BCM2835 || ARCH_BCM_IPROC || COMPILE_TEST

drivers/mmc/host/Makefile

@@ -21,6 +21,7 @@ obj-$(CONFIG_MMC_SDHCI_PXAV2)	+= sdhci-pxav2.o
 obj-$(CONFIG_MMC_SDHCI_S3C)	+= sdhci-s3c.o
 obj-$(CONFIG_MMC_SDHCI_SIRF)   	+= sdhci-sirf.o
 obj-$(CONFIG_MMC_SDHCI_F_SDH30)	+= sdhci_f_sdh30.o
+obj-$(CONFIG_MMC_SDHCI_MILBEAUT)	+= sdhci-milbeaut.o
 obj-$(CONFIG_MMC_SDHCI_SPEAR)	+= sdhci-spear.o
 obj-$(CONFIG_MMC_SDHCI_AM654)	+= sdhci_am654.o
 obj-$(CONFIG_MMC_WBSD)		+= wbsd.o

drivers/mmc/host/sdhci-milbeaut.c

@@ -0,0 +1,362 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2013 - 2015 Fujitsu Semiconductor, Ltd
+ *              Vincent Yang <vincent.yang@tw.fujitsu.com>
+ * Copyright (C) 2015 Linaro Ltd  Andy Green <andy.green@linaro.org>
+ * Copyright (C) 2019 Socionext Inc.
+ *              Takao Orito <orito.takao@socionext.com>
+ */
+
+#include <linux/bits.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/property.h>
+
+#include "sdhci-pltfm.h"
+#include "sdhci_f_sdh30.h"
+
+/* milbeaut bridge controller register */
+#define MLB_SOFT_RESET		0x0200
+#define  MLB_SOFT_RESET_RSTX		BIT(0)
+
+#define MLB_WP_CD_LED_SET	0x0210
+#define  MLB_WP_CD_LED_SET_LED_INV  BIT(2)
+
+#define MLB_CR_SET			0x0220
+#define  MLB_CR_SET_CR_TOCLKUNIT       BIT(24)
+#define  MLB_CR_SET_CR_TOCLKFREQ_SFT   (16)
+#define  MLB_CR_SET_CR_TOCLKFREQ_MASK  (0x3F << MLB_CR_SET_CR_TOCLKFREQ_SFT)
+#define  MLB_CR_SET_CR_BCLKFREQ_SFT    (8)
+#define  MLB_CR_SET_CR_BCLKFREQ_MASK   (0xFF << MLB_CR_SET_CR_BCLKFREQ_SFT)
+#define  MLB_CR_SET_CR_RTUNTIMER_SFT   (4)
+#define  MLB_CR_SET_CR_RTUNTIMER_MASK  (0xF << MLB_CR_SET_CR_RTUNTIMER_SFT)
+
+#define MLB_SD_TOCLK_I_DIV  16
+#define MLB_TOCLKFREQ_UNIT_THRES    16000000
+#define MLB_CAL_TOCLKFREQ_MHZ(rate) (rate / MLB_SD_TOCLK_I_DIV / 1000000)
+#define MLB_CAL_TOCLKFREQ_KHZ(rate) (rate / MLB_SD_TOCLK_I_DIV / 1000)
+#define MLB_TOCLKFREQ_MAX   63
+#define MLB_TOCLKFREQ_MIN    1
+
+#define MLB_SD_BCLK_I_DIV   4
+#define MLB_CAL_BCLKFREQ(rate)  (rate / MLB_SD_BCLK_I_DIV / 1000000)
+#define MLB_BCLKFREQ_MAX        255
+#define MLB_BCLKFREQ_MIN          1
+
+#define MLB_CDR_SET			0x0230
+#define MLB_CDR_SET_CLK2POW16	3
+
+struct f_sdhost_priv {
+	struct clk *clk_iface;
+	struct clk *clk;
+	struct device *dev;
+	bool enable_cmd_dat_delay;
+};
+
+static void sdhci_milbeaut_soft_voltage_switch(struct sdhci_host *host)
+{
+	u32 ctrl = 0;
+
+	usleep_range(2500, 3000);
+	ctrl = sdhci_readl(host, F_SDH30_IO_CONTROL2);
+	ctrl |= F_SDH30_CRES_O_DN;
+	sdhci_writel(host, ctrl, F_SDH30_IO_CONTROL2);
+	ctrl |= F_SDH30_MSEL_O_1_8;
+	sdhci_writel(host, ctrl, F_SDH30_IO_CONTROL2);
+
+	ctrl &= ~F_SDH30_CRES_O_DN;
+	sdhci_writel(host, ctrl, F_SDH30_IO_CONTROL2);
+	usleep_range(2500, 3000);
+
+	ctrl = sdhci_readl(host, F_SDH30_TUNING_SETTING);
+	ctrl |= F_SDH30_CMD_CHK_DIS;
+	sdhci_writel(host, ctrl, F_SDH30_TUNING_SETTING);
+}
+
+static unsigned int sdhci_milbeaut_get_min_clock(struct sdhci_host *host)
+{
+	return F_SDH30_MIN_CLOCK;
+}
+
+static void sdhci_milbeaut_reset(struct sdhci_host *host, u8 mask)
+{
+	struct f_sdhost_priv *priv = sdhci_priv(host);
+	u16 clk;
+	u32 ctl;
+	ktime_t timeout;
+
+	clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
+	clk = (clk & ~SDHCI_CLOCK_CARD_EN) | SDHCI_CLOCK_INT_EN;
+	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+
+	sdhci_reset(host, mask);
+
+	clk |= SDHCI_CLOCK_CARD_EN;
+	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+
+	timeout = ktime_add_ms(ktime_get(), 10);
+	while (1) {
+		bool timedout = ktime_after(ktime_get(), timeout);
+
+		clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
+		if (clk & SDHCI_CLOCK_INT_STABLE)
+			break;
+		if (timedout) {
+			pr_err("%s: Internal clock never stabilised.\n",
+				mmc_hostname(host->mmc));
+			sdhci_dumpregs(host);
+			return;
+		}
+		udelay(10);
+	}
+
+	if (priv->enable_cmd_dat_delay) {
+		ctl = sdhci_readl(host, F_SDH30_ESD_CONTROL);
+		ctl |= F_SDH30_CMD_DAT_DELAY;
+		sdhci_writel(host, ctl, F_SDH30_ESD_CONTROL);
+	}
+}
+
+static void sdhci_milbeaut_set_power(struct sdhci_host *host,
+			unsigned char mode, unsigned short vdd)
+{
+	if (!IS_ERR(host->mmc->supply.vmmc)) {
+		struct mmc_host *mmc = host->mmc;
+
+		mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, vdd);
+	}
+	sdhci_set_power_noreg(host, mode, vdd);
+}
+
+static const struct sdhci_ops sdhci_milbeaut_ops = {
+	.voltage_switch = sdhci_milbeaut_soft_voltage_switch,
+	.get_min_clock = sdhci_milbeaut_get_min_clock,
+	.reset = sdhci_milbeaut_reset,
+	.set_clock = sdhci_set_clock,
+	.set_bus_width = sdhci_set_bus_width,
+	.set_uhs_signaling = sdhci_set_uhs_signaling,
+	.set_power = sdhci_milbeaut_set_power,
+};
+
+static void sdhci_milbeaut_bridge_reset(struct sdhci_host *host,
+						int reset_flag)
+{
+	if (reset_flag)
+		sdhci_writel(host, 0, MLB_SOFT_RESET);
+	else
+		sdhci_writel(host, MLB_SOFT_RESET_RSTX, MLB_SOFT_RESET);
+}
+
+static void sdhci_milbeaut_bridge_init(struct sdhci_host *host,
+						int rate)
+{
+	u32 val, clk;
+
+	/* IO_SDIO_CR_SET should be set while reset */
+	val = sdhci_readl(host, MLB_CR_SET);
+	val &= ~(MLB_CR_SET_CR_TOCLKFREQ_MASK | MLB_CR_SET_CR_TOCLKUNIT |
+			MLB_CR_SET_CR_BCLKFREQ_MASK);
+	if (rate >= MLB_TOCLKFREQ_UNIT_THRES) {
+		clk = MLB_CAL_TOCLKFREQ_MHZ(rate);
+		clk = min_t(u32, MLB_TOCLKFREQ_MAX, clk);
+		val |= MLB_CR_SET_CR_TOCLKUNIT |
+			(clk << MLB_CR_SET_CR_TOCLKFREQ_SFT);
+	} else {
+		clk = MLB_CAL_TOCLKFREQ_KHZ(rate);
+		clk = min_t(u32, MLB_TOCLKFREQ_MAX, clk);
+		clk = max_t(u32, MLB_TOCLKFREQ_MIN, clk);
+		val |= clk << MLB_CR_SET_CR_TOCLKFREQ_SFT;
+	}
+
+	clk = MLB_CAL_BCLKFREQ(rate);
+	clk = min_t(u32, MLB_BCLKFREQ_MAX, clk);
+	clk = max_t(u32, MLB_BCLKFREQ_MIN, clk);
+	val |=  clk << MLB_CR_SET_CR_BCLKFREQ_SFT;
+	val &= ~MLB_CR_SET_CR_RTUNTIMER_MASK;
+	sdhci_writel(host, val, MLB_CR_SET);
+
+	sdhci_writel(host, MLB_CDR_SET_CLK2POW16, MLB_CDR_SET);
+
+	sdhci_writel(host, MLB_WP_CD_LED_SET_LED_INV, MLB_WP_CD_LED_SET);
+}
+
+static void sdhci_milbeaut_vendor_init(struct sdhci_host *host)
+{
+	struct f_sdhost_priv *priv = sdhci_priv(host);
+	u32 ctl;
+
+	ctl = sdhci_readl(host, F_SDH30_IO_CONTROL2);
+	ctl |= F_SDH30_CRES_O_DN;
+	sdhci_writel(host, ctl, F_SDH30_IO_CONTROL2);
+	ctl &= ~F_SDH30_MSEL_O_1_8;
+	sdhci_writel(host, ctl, F_SDH30_IO_CONTROL2);
+	ctl &= ~F_SDH30_CRES_O_DN;
+	sdhci_writel(host, ctl, F_SDH30_IO_CONTROL2);
+
+	ctl = sdhci_readw(host, F_SDH30_AHB_CONFIG);
+	ctl |= F_SDH30_SIN | F_SDH30_AHB_INCR_16 | F_SDH30_AHB_INCR_8 |
+	       F_SDH30_AHB_INCR_4;
+	ctl &= ~(F_SDH30_AHB_BIGED | F_SDH30_BUSLOCK_EN);
+	sdhci_writew(host, ctl, F_SDH30_AHB_CONFIG);
+
+	if (priv->enable_cmd_dat_delay) {
+		ctl = sdhci_readl(host, F_SDH30_ESD_CONTROL);
+		ctl |= F_SDH30_CMD_DAT_DELAY;
+		sdhci_writel(host, ctl, F_SDH30_ESD_CONTROL);
+	}
+}
+
+static const struct of_device_id mlb_dt_ids[] = {
+	{
+		.compatible = "socionext,milbeaut-m10v-sdhci-3.0",
+	},
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mlb_dt_ids);
+
+static void sdhci_milbeaut_init(struct sdhci_host *host)
+{
+	struct f_sdhost_priv *priv = sdhci_priv(host);
+	int rate = clk_get_rate(priv->clk);
+	u16 ctl;
+
+	sdhci_milbeaut_bridge_reset(host, 0);
+
+	ctl = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
+	ctl &= ~(SDHCI_CLOCK_CARD_EN | SDHCI_CLOCK_INT_EN);
+	sdhci_writew(host, ctl, SDHCI_CLOCK_CONTROL);
+
+	sdhci_milbeaut_bridge_reset(host, 1);
+
+	sdhci_milbeaut_bridge_init(host, rate);
+	sdhci_milbeaut_bridge_reset(host, 0);
+
+	sdhci_milbeaut_vendor_init(host);
+}
+
+static int sdhci_milbeaut_probe(struct platform_device *pdev)
+{
+	struct sdhci_host *host;
+	struct device *dev = &pdev->dev;
+	struct resource *res;
+	int irq, ret = 0;
+	struct f_sdhost_priv *priv;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(dev, "%s: no irq specified\n", __func__);
+		return irq;
+	}
+
+	host = sdhci_alloc_host(dev, sizeof(struct f_sdhost_priv));
+	if (IS_ERR(host))
+		return PTR_ERR(host);
+
+	priv = sdhci_priv(host);
+	priv->dev = dev;
+
+	host->quirks = SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC |
+			   SDHCI_QUIRK_INVERTED_WRITE_PROTECT |
+			   SDHCI_QUIRK_CLOCK_BEFORE_RESET |
+			   SDHCI_QUIRK_DELAY_AFTER_POWER;
+	host->quirks2 = SDHCI_QUIRK2_SUPPORT_SINGLE |
+			SDHCI_QUIRK2_TUNING_WORK_AROUND |
+			SDHCI_QUIRK2_PRESET_VALUE_BROKEN;
+
+	priv->enable_cmd_dat_delay = device_property_read_bool(dev,
+						"fujitsu,cmd-dat-delay-select");
+
+	ret = mmc_of_parse(host->mmc);
+	if (ret)
+		goto err;
+
+	platform_set_drvdata(pdev, host);
+
+	host->hw_name = "f_sdh30";
+	host->ops = &sdhci_milbeaut_ops;
+	host->irq = irq;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	host->ioaddr = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(host->ioaddr)) {
+		ret = PTR_ERR(host->ioaddr);
+		goto err;
+	}
+
+	if (dev_of_node(dev)) {
+		sdhci_get_of_property(pdev);
+
+		priv->clk_iface = devm_clk_get(&pdev->dev, "iface");
+		if (IS_ERR(priv->clk_iface)) {
+			ret = PTR_ERR(priv->clk_iface);
+			goto err;
+		}
+
+		ret = clk_prepare_enable(priv->clk_iface);
+		if (ret)
+			goto err;
+
+		priv->clk = devm_clk_get(&pdev->dev, "core");
+		if (IS_ERR(priv->clk)) {
+			ret = PTR_ERR(priv->clk);
+			goto err_clk;
+		}
+
+		ret = clk_prepare_enable(priv->clk);
+		if (ret)
+			goto err_clk;
+	}
+
+	sdhci_milbeaut_init(host);
+
+	ret = sdhci_add_host(host);
+	if (ret)
+		goto err_add_host;
+
+	return 0;
+
+err_add_host:
+	clk_disable_unprepare(priv->clk);
+err_clk:
+	clk_disable_unprepare(priv->clk_iface);
+err:
+	sdhci_free_host(host);
+	return ret;
+}
+
+static int sdhci_milbeaut_remove(struct platform_device *pdev)
+{
+	struct sdhci_host *host = platform_get_drvdata(pdev);
+	struct f_sdhost_priv *priv = sdhci_priv(host);
+
+	sdhci_remove_host(host, readl(host->ioaddr + SDHCI_INT_STATUS) ==
+			  0xffffffff);
+
+	clk_disable_unprepare(priv->clk_iface);
+	clk_disable_unprepare(priv->clk);
+
+	sdhci_free_host(host);
+	platform_set_drvdata(pdev, NULL);
+
+	return 0;
+}
+
+static struct platform_driver sdhci_milbeaut_driver = {
+	.driver = {
+		.name = "sdhci-milbeaut",
+		.of_match_table = of_match_ptr(mlb_dt_ids),
+	},
+	.probe	= sdhci_milbeaut_probe,
+	.remove	= sdhci_milbeaut_remove,
+};
+
+module_platform_driver(sdhci_milbeaut_driver);
+
+MODULE_DESCRIPTION("MILBEAUT SD Card Controller driver");
+MODULE_AUTHOR("Takao Orito <orito.takao@socionext.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:sdhci-milbeaut");