[PATCH v2] arm: exynos: Read default MMC device from XOM[7:5] pins

[Marek Szyprowski]

XOM pins provide information for iROM bootloader about the boot device.
Those pins are mapped to lower bits of OP_MODE register (0x10000008),
which is common for all Exynos SoC variants. Set the default MMC device id
to reflect the boot device selected by XOM[7:5] pins (2 for the SD or 0 for
the eMMC).

Signed-off-by: Marek Szyprowski <m.szyprowski at samsung.com>
---
v2:
- store mmc boot device to ${mmcbootdev} env
- print information about boot mmc device
---
 arch/arm/mach-exynos/include/mach/cpu.h |  1 +
 board/samsung/common/board.c            | 28 +++++++++++++++++++++++++
 configs/odroid-xu3_defconfig            |  1 +
 configs/odroid_defconfig                |  1 +
 4 files changed, 31 insertions(+)

diff --git a/arch/arm/mach-exynos/include/mach/cpu.h b/arch/arm/mach-exynos/include/mach/cpu.h
index 766edeeb29..fb5fdaf3ba 100644
--- a/arch/arm/mach-exynos/include/mach/cpu.h
+++ b/arch/arm/mach-exynos/include/mach/cpu.h
@@ -17,6 +17,7 @@
 
 #define EXYNOS4_GPIO_PART3_BASE		0x03860000
 #define EXYNOS4_PRO_ID			0x10000000
+#define EXYNOS4_OP_MODE			0x10000008
 #define EXYNOS4_SYSREG_BASE		0x10010000
 #define EXYNOS4_POWER_BASE		0x10020000
 #define EXYNOS4_SWRESET			0x10020400
diff --git a/board/samsung/common/board.c b/board/samsung/common/board.c
index ee2fc7971e..cb94ced54e 100644
--- a/board/samsung/common/board.c
+++ b/board/samsung/common/board.c
@@ -24,6 +24,8 @@
 #include <asm/arch/sromc.h>
 #include <lcd.h>
 #include <i2c.h>
+#include <mmc.h>
+#include <stdio_dev.h>
 #include <usb.h>
 #include <dwc3-uboot.h>
 #include <samsung/misc.h>
@@ -42,6 +44,20 @@ __weak int exynos_power_init(void)
 	return 0;
 }
 
+/**
+ * get_boot_mmc_dev() - read boot MMC device id from XOM[7:5] pins.
+ */
+static int get_boot_mmc_dev(void)
+{
+	u32 mode = readl(EXYNOS4_OP_MODE) & 0x1C;
+
+	if (mode == 0x04)
+		return 2; /* MMC2: SD */
+
+	/* MMC0: eMMC or unknown */
+	return 0;
+}
+
 #if defined CONFIG_EXYNOS_TMU
 /* Boot Time Thermal Analysis for SoC temperature threshold breach */
 static void boot_temp_check(void)
@@ -280,6 +296,8 @@ int board_late_init(void)
 {
 	struct udevice *dev;
 	int ret;
+	int mmcbootdev = get_boot_mmc_dev();
+	char mmcbootdev_str[16];
 
 	stdio_print_current_devices();
 	ret = uclass_first_device_err(UCLASS_CROS_EC, &dev);
@@ -292,6 +310,11 @@ int board_late_init(void)
 		panic("Cannot init cros-ec device");
 		return -1;
 	}
+
+	printf("Boot device: MMC(%u)\n", mmcbootdev);
+	sprintf(mmcbootdev_str, "%u", mmcbootdev);
+	env_set("mmcbootdev", mmcbootdev_str);
+
 	return 0;
 }
 #endif
@@ -359,3 +382,8 @@ int board_usb_cleanup(int index, enum usb_init_type init)
 #endif
 	return 0;
 }
+
+int mmc_get_env_dev(void)
+{
+	return get_boot_mmc_dev();
+}
diff --git a/configs/odroid-xu3_defconfig b/configs/odroid-xu3_defconfig
index 20038d4197..2e982e1b53 100644
--- a/configs/odroid-xu3_defconfig
+++ b/configs/odroid-xu3_defconfig
@@ -14,6 +14,7 @@ CONFIG_FIT_BEST_MATCH=y
 CONFIG_SILENT_CONSOLE=y
 CONFIG_CONSOLE_MUX=y
 CONFIG_MISC_INIT_R=y
+CONFIG_BOARD_LATE_INIT=y
 # CONFIG_DISPLAY_BOARDINFO is not set
 CONFIG_DISPLAY_BOARDINFO_LATE=y
 CONFIG_BOARD_TYPES=y
diff --git a/configs/odroid_defconfig b/configs/odroid_defconfig
index be914e4caf..e4392e477e 100644
--- a/configs/odroid_defconfig
+++ b/configs/odroid_defconfig
@@ -17,6 +17,7 @@ CONFIG_BOOTARGS="Please use defined boot"
 CONFIG_SYS_CONSOLE_IS_IN_ENV=y
 CONFIG_SYS_CONSOLE_INFO_QUIET=y
 CONFIG_MISC_INIT_R=y
+CONFIG_BOARD_LATE_INIT=y
 CONFIG_BOARD_TYPES=y
 CONFIG_SYS_PROMPT="Odroid # "
 # CONFIG_CMD_XIMG is not set
-- 
2.17.1