stm32mp: use device sequence number in boot_instance variable

Use the device sequence number in boot_instance variable
and no more the SDMMC instance provided by ROM code/TF-A.

After this patch we don't need to define the mmc alias in
device tree, for example:
  mmc0 = &sdmmc1;
  mmc1 = &sdmmc2;
  mmc2 = &sdmmc3;
to have a correct mapping between the ROM code boot device =
"${boot_device}${boot_instance}" and the MMC device in U-Boot.

With this patch the 'mmc0' device (used in mmc commands) is
always used when only one instance sdmmc is activated in device
tree, even if it is only the sdmmc2 or sdmmc3.

Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>

1 files changed, 27 insertions, 8 deletions

diff --git a/board/st/stm32mp1/stm32mp1.c b/board/st/stm32mp1/stm32mp1.c
index 18b8870..2faf5c8 100644
--- a/board/st/stm32mp1/stm32mp1.c
+++ b/board/st/stm32mp1/stm32mp1.c
@@ -841,6 +841,31 @@ const char *env_ext4_get_intf(void)
 	}
 }
 
+int mmc_get_boot(void)
+{
+	struct udevice *dev;
+	u32 boot_mode = get_bootmode();
+	unsigned int instance = (boot_mode & TAMP_BOOT_INSTANCE_MASK) - 1;
+	char cmd[20];
+	const u32 sdmmc_addr[] = {
+		STM32_SDMMC1_BASE,
+		STM32_SDMMC2_BASE,
+		STM32_SDMMC3_BASE
+	};
+
+	if (instance > ARRAY_SIZE(sdmmc_addr))
+		return 0;
+
+	/* search associated sdmmc node in devicetree */
+	snprintf(cmd, sizeof(cmd), "mmc@%x", sdmmc_addr[instance]);
+	if (uclass_get_device_by_name(UCLASS_MMC, cmd, &dev)) {
+		log_err("mmc%d = %s not found in device tree!\n", instance, cmd);
+		return 0;
+	}
+
+	return dev_seq(dev);
+};
+
 const char *env_ext4_get_dev_part(void)
 {
 	static char *const env_dev_part =
@@ -854,22 +879,16 @@ const char *env_ext4_get_dev_part(void)
 	if (strlen(env_dev_part) > 0)
 		return env_dev_part;
 
-	u32 bootmode = get_bootmode();
-
-	return dev_part[(bootmode & TAMP_BOOT_INSTANCE_MASK) - 1];
+	return dev_part[mmc_get_boot()];
 }
 
 int mmc_get_env_dev(void)
 {
-	u32 bootmode;
-
 	if (CONFIG_SYS_MMC_ENV_DEV >= 0)
 		return CONFIG_SYS_MMC_ENV_DEV;
 
-	bootmode = get_bootmode();
-
 	/* use boot instance to select the correct mmc device identifier */
-	return (bootmode & TAMP_BOOT_INSTANCE_MASK) - 1;
+	return mmc_get_boot();
 }
 
 #if defined(CONFIG_OF_BOARD_SETUP)