[U-Boot] [PATCH] spl: mmc: make eMMC HW boot partition configuration optional

[Anatolij Gustschin]

Loading U-Boot on i.MX8QXP MEK board is broken since recent changes
in spl_mmc:

  U-Boot SPL 2019.10-00162-gff5bd397e4 (Oct 18 2019 - 15:50:45 +0200)
  Normal Boot
  WDT:   Not found!
  Trying to boot from MMC2_2
  Load image from MMC/SD 0x46400
  spl: mmc partition switch failed
  SPL: failed to boot from all boot devices
  ### ERROR ### Please RESET the board ###

The newly added CONFIG_SYS_MMCSD_RAW_MODE_EMMC_BOOT_PARTITION option
is selected automatically and overrides the EXT_CSC_PART_CONFIG
configurations with default value, always selecting the eMMC boot
partition 1. Boards which place U-Boot image in other partitions
became not bootable.

Fix this by making the eMMC HW boot partition selection optional.

Fixes: 17241ea0543a (spl: mmc: Add option to set eMMC HW boot partition)
Signed-off-by: Anatolij Gustschin <agust at denx.de>
---
Hi Tom,

Many other boards (using CONFIG_SUPPORT_EMMC_BOOT) are affected, too.
So, this (or other suitable fix) should be applied ASAP.

Thanks,
Anatolij

 common/spl/Kconfig | 28 ++++++++++++++++++++++------
 1 file changed, 22 insertions(+), 6 deletions(-)

diff --git a/common/spl/Kconfig b/common/spl/Kconfig
index 562eafe2e5..86d7edfee1 100644
--- a/common/spl/Kconfig
+++ b/common/spl/Kconfig
@@ -325,12 +325,6 @@ config SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR
 	  Address on the MMC to load U-Boot from, when the MMC is being used
 	  in raw mode. Units: MMC sectors (1 sector = 512 bytes).
 
-config SYS_MMCSD_RAW_MODE_EMMC_BOOT_PARTITION
-	int "Number of the eMMC boot partition to use"
-	default 1
-	help
-	  eMMC boot partition number to use when the eMMC in raw mode.
-
 config SYS_MMCSD_RAW_MODE_U_BOOT_USE_PARTITION
 	bool "MMC Raw mode: by partition"
 	help
@@ -359,6 +353,28 @@ config SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION_TYPE
 	  Partition Type on the MMC to load U-Boot from, when the MMC is being
 	  used in raw mode.
 
+config SUPPORT_EMMC_BOOT_OVERRIDE_PART_CONFIG
+	bool "Override eMMC EXT_CSC_PART_CONFIG by user defined partition"
+	depends on SUPPORT_EMMC_BOOT
+	help
+	  eMMC boot partition is normally configured by the bits of the EXT_CSD
+	  register (EXT_CSC_PART_CONFIG), BOOT_PARTITION_ENABLE field. In some
+	  cases it might be required in SPL to load the image from different
+	  partition than the partition selected by EXT_CSC_PART_CONFIG register.
+	  Enable this option if you intend to use an eMMC boot partition other
+	  then selected via EXT_CSC_PART_CONFIG register and specify the custom
+	  partition number by the CONFIG_SYS_MMCSD_RAW_MODE_EMMC_BOOT_PARTITION
+	  option.
+
+config SYS_MMCSD_RAW_MODE_EMMC_BOOT_PARTITION
+	int "Number of the eMMC boot partition to use"
+	depends on SUPPORT_EMMC_BOOT_OVERRIDE_PART_CONFIG
+	default 1
+	help
+	  eMMC boot partition number to use when the eMMC in raw mode and
+	  the eMMC EXT_CSC_PART_CONFIG selection should be overridden in SPL
+	  by user defined partition number.
+
 config SPL_CRC32_SUPPORT
 	bool "Support CRC32"
 	default y if SPL_LEGACY_IMAGE_SUPPORT
-- 
2.17.1