STiH410: Add STi SDHCI driver

Add SDHCI host controller found on STMicroelectronics SoCs

On some ST SoCs, i.e. STiH407/STiH410, the MMC devices can live
inside a dedicated flashSS sub-system that provides an extend subset
of registers that can be used to configure the Arasan MMC/SD Host
Controller.

This means, that the SDHCI Arasan Controller can be configured to be
eMMC4.5 or 4.3 spec compliant.

W/o these settings the SDHCI will configure and use the MMC/SD
controller with limited features e.g. PIO mode, no DMA, no HS etc.

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>

3 files changed, 149 insertions, 0 deletions

diff --git a/drivers/mmc/Kconfig b/drivers/mmc/Kconfig
index 01d1dbfb1b5..ea5ea087f37 100644
--- a/drivers/mmc/Kconfig
+++ b/drivers/mmc/Kconfig
@@ -299,6 +299,13 @@ config MMC_SDHCI_SPEAR
 
 	  If unsure, say N.
 
+config MMC_SDHCI_STI
+	bool "SDHCI support for STMicroelectronics SoC"
+	depends on MMC_SDHCI
+	help
+	  This selects the Secure Digital Host Controller Interface (SDHCI)
+	  on STMicroelectronics STiH410 SoC.
+
 config MMC_SDHCI_XENON
 	bool "SDHCI support for the Xenon SDHCI controller"
 	depends on MMC_SDHCI && DM_MMC && OF_CONTROL
diff --git a/drivers/mmc/Makefile b/drivers/mmc/Makefile
index 8e922db3f1a..6a488f1db99 100644
--- a/drivers/mmc/Makefile
+++ b/drivers/mmc/Makefile
@@ -61,6 +61,7 @@ obj-$(CONFIG_MMC_SDHCI_PIC32)		+= pic32_sdhci.o
 obj-$(CONFIG_MMC_SDHCI_ROCKCHIP)	+= rockchip_sdhci.o
 obj-$(CONFIG_MMC_SDHCI_S5P)		+= s5p_sdhci.o
 obj-$(CONFIG_MMC_SDHCI_SPEAR)		+= spear_sdhci.o
+obj-$(CONFIG_MMC_SDHCI_STI) 		+= sti_sdhci.o
 obj-$(CONFIG_MMC_SDHCI_TEGRA)		+= tegra_mmc.o
 obj-$(CONFIG_MMC_SDHCI_XENON)		+= xenon_sdhci.o
 obj-$(CONFIG_MMC_SDHCI_ZYNQ)		+= zynq_sdhci.o
diff --git a/drivers/mmc/sti_sdhci.c b/drivers/mmc/sti_sdhci.c
new file mode 100644
index 00000000000..2a070820364
--- /dev/null
+++ b/drivers/mmc/sti_sdhci.c
@@ -0,0 +1,141 @@
+/*
+ *  Copyright (c) 2017
+ *  Patrice Chotard <patrice.chotard@st.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <mmc.h>
+#include <sdhci.h>
+#include <asm/arch/sdhci.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct sti_sdhci_plat {
+	struct mmc_config cfg;
+	struct mmc mmc;
+};
+
+/*
+ * used to get access to MMC1 reset,
+ * will be removed when STi reset driver will be available
+ */
+#define STIH410_SYSCONF5_BASE		0x092b0000
+
+/**
+ * sti_mmc_core_config: configure the Arasan HC
+ * @regbase: base address
+ * @mmc_instance: mmc instance id
+ * Description: this function is to configure the Arasan MMC HC.
+ * This should be called when the system starts in case of, on the SoC,
+ * it is needed to configure the host controller.
+ * This happens on some SoCs, i.e. StiH410, where the MMC0 inside the flashSS
+ * needs to be configured as MMC 4.5 to have full capabilities.
+ * W/o these settings the SDHCI could configure and use the embedded controller
+ * with limited features.
+ */
+static void sti_mmc_core_config(const u32 regbase, int mmc_instance)
+{
+	unsigned long *sysconf;
+
+	/* only MMC1 has a reset line */
+	if (mmc_instance) {
+		sysconf = (unsigned long *)(STIH410_SYSCONF5_BASE +
+			  ST_MMC_CCONFIG_REG_5);
+		generic_set_bit(SYSCONF_MMC1_ENABLE_BIT, sysconf);
+	}
+
+	writel(STI_FLASHSS_MMC_CORE_CONFIG_1,
+	       regbase + FLASHSS_MMC_CORE_CONFIG_1);
+
+	if (mmc_instance) {
+		writel(STI_FLASHSS_MMC_CORE_CONFIG2,
+		       regbase + FLASHSS_MMC_CORE_CONFIG_2);
+		writel(STI_FLASHSS_MMC_CORE_CONFIG3,
+		       regbase + FLASHSS_MMC_CORE_CONFIG_3);
+	} else {
+		writel(STI_FLASHSS_SDCARD_CORE_CONFIG2,
+		       regbase + FLASHSS_MMC_CORE_CONFIG_2);
+		writel(STI_FLASHSS_SDCARD_CORE_CONFIG3,
+		       regbase + FLASHSS_MMC_CORE_CONFIG_3);
+	}
+	writel(STI_FLASHSS_MMC_CORE_CONFIG4,
+	       regbase + FLASHSS_MMC_CORE_CONFIG_4);
+}
+
+static int sti_sdhci_probe(struct udevice *dev)
+{
+	struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev);
+	struct sti_sdhci_plat *plat = dev_get_platdata(dev);
+	struct sdhci_host *host = dev_get_priv(dev);
+	int ret, mmc_instance;
+
+	/*
+	 * identify current mmc instance, mmc1 has a reset, not mmc0
+	 * MMC0 is wired to the SD slot,
+	 * MMC1 is wired on the high speed connector
+	 */
+
+	if (fdt_getprop(gd->fdt_blob, dev_of_offset(dev), "resets", NULL))
+		mmc_instance = 1;
+	else
+		mmc_instance = 0;
+
+	sti_mmc_core_config((const u32) host->ioaddr, mmc_instance);
+
+	host->quirks = SDHCI_QUIRK_WAIT_SEND_CMD |
+		       SDHCI_QUIRK_32BIT_DMA_ADDR |
+		       SDHCI_QUIRK_NO_HISPD_BIT;
+
+	host->host_caps = MMC_MODE_DDR_52MHz;
+
+	ret = sdhci_setup_cfg(&plat->cfg, host, 50000000, 400000);
+	if (ret)
+		return ret;
+
+	host->mmc = &plat->mmc;
+	host->mmc->priv = host;
+	host->mmc->dev = dev;
+	upriv->mmc = host->mmc;
+
+	return sdhci_probe(dev);
+}
+
+static int sti_sdhci_ofdata_to_platdata(struct udevice *dev)
+{
+	struct sdhci_host *host = dev_get_priv(dev);
+
+	host->name = strdup(dev->name);
+	host->ioaddr = (void *)dev_get_addr(dev);
+
+	host->bus_width = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
+					 "bus-width", 4);
+
+	return 0;
+}
+
+static int sti_sdhci_bind(struct udevice *dev)
+{
+	struct sti_sdhci_plat *plat = dev_get_platdata(dev);
+
+	return sdhci_bind(dev, &plat->mmc, &plat->cfg);
+}
+
+static const struct udevice_id sti_sdhci_ids[] = {
+	{ .compatible = "st,sdhci" },
+	{ }
+};
+
+U_BOOT_DRIVER(sti_mmc) = {
+	.name = "sti_sdhci",
+	.id = UCLASS_MMC,
+	.of_match = sti_sdhci_ids,
+	.bind = sti_sdhci_bind,
+	.ops = &sdhci_ops,
+	.ofdata_to_platdata = sti_sdhci_ofdata_to_platdata,
+	.probe = sti_sdhci_probe,
+	.priv_auto_alloc_size = sizeof(struct sdhci_host),
+	.platdata_auto_alloc_size = sizeof(struct sti_sdhci_plat),
+};