[PATCH RFC u-boot-mvebu 12/59] arm: mvebu: spl: Fix support for loading U-Boot proper from SD card

[Pali Rohár]

Marvell BootROM loads MMC image from sector 0 (HW boot or data partition)
and SD image from sector 1.

So for SD card booting it is needed to not use constant CONFIG MMC options
and instead of them it is needed to define functions spl_mmc_boot_mode()
spl_mmc_get_uboot_raw_sector() which determinate offsets at SPL runtime
based on MMC or SD card.

Calculation of SD card sector expects following values:
CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_DATA_PART_OFFSET=0
CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR=0

Fixes: 2226ca173486 ("arm: mvebu: Load U-Boot proper binary in SPL code based on kwbimage header")
Signed-off-by: Pali Rohár <pali at kernel.org>
---
 arch/arm/mach-mvebu/Kconfig |  1 +
 arch/arm/mach-mvebu/spl.c   | 40 ++++++++++++++++++++++++++++---------
 2 files changed, 32 insertions(+), 9 deletions(-)

diff --git a/arch/arm/mach-mvebu/Kconfig b/arch/arm/mach-mvebu/Kconfig
index 5303b1cbb965..2863babefbe3 100644
--- a/arch/arm/mach-mvebu/Kconfig
+++ b/arch/arm/mach-mvebu/Kconfig
@@ -331,6 +331,7 @@ config MVEBU_SPL_BOOT_DEVICE_MMC
 	imply SPL_LIBDISK_SUPPORT
 	imply SPL_MMC
 	select SUPPORT_EMMC_BOOT if SPL_MMC
+	select SYS_MMCSD_RAW_MODE_U_BOOT_USE_SECTOR if SPL_MMC
 	select SPL_BOOTROM_SUPPORT
 
 config MVEBU_SPL_BOOT_DEVICE_SATA
diff --git a/arch/arm/mach-mvebu/spl.c b/arch/arm/mach-mvebu/spl.c
index 0a809e91349c..02528e025d8c 100644
--- a/arch/arm/mach-mvebu/spl.c
+++ b/arch/arm/mach-mvebu/spl.c
@@ -33,14 +33,27 @@
 #endif
 
 /*
- * When loading U-Boot via SPL from eMMC (in Marvell terminology SDIO), the
- * kwbimage main header is stored at sector 0. U-Boot SPL needs to parse this
- * header and figure out at which sector the U-Boot proper binary is stored.
- * Partition booting is therefore not supported and CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR
- * and CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_DATA_PART_OFFSET need to point to the
- * kwbimage main header.
+ * When loading U-Boot via SPL from eMMC, the kwbimage main header is stored at
+ * sector 0 and either on HW boot partition or on data partition. Choice of HW
+ * partition depends on what is configured in eMMC EXT_CSC register.
+ * When loading U-Boot via SPL from SD card, the kwbimage main header is stored
+ * at sector 1.
+ * Therefore MBR/GPT partition booting, fixed sector number and fixed eMMC HW
+ * partition number are unsupported due to limitation of Marvell BootROM.
+ * Correct sector number must be determined as runtime in mvebu SPL code based
+ * on the detected boot source. Otherwise U-Boot SPL would not be able to load
+ * U-Boot proper.
+ * Runtime mvebu SPL sector calculation code expects:
+ * - CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_DATA_PART_OFFSET=0
+ * - CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR=0
  */
 #ifdef CONFIG_SPL_MMC
+#ifdef CONFIG_SYS_MMCSD_FS_BOOT
+#error CONFIG_SYS_MMCSD_FS_BOOT is unsupported
+#endif
+#ifdef CONFIG_SYS_MMCSD_FS_BOOT_PARTITION
+#error CONFIG_SYS_MMCSD_FS_BOOT_PARTITION is unsupported
+#endif
 #ifdef CONFIG_SUPPORT_EMMC_BOOT_OVERRIDE_PART_CONFIG
 #error CONFIG_SUPPORT_EMMC_BOOT_OVERRIDE_PART_CONFIG is unsupported
 #endif
@@ -50,10 +63,14 @@
 #ifdef CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_USE_PARTITION
 #error CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_USE_PARTITION is unsupported
 #endif
-#if defined(CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR) && CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR != 0
+#ifndef CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_USE_SECTOR
+#error CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_USE_SECTOR must be enabled for SD/eMMC boot support
+#endif
+#if !defined(CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR) || \
+    CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR != 0
 #error CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR must be set to 0
 #endif
-#if defined(CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_DATA_PART_OFFSET) && \
+#if !defined(CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_DATA_PART_OFFSET) || \
     CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_DATA_PART_OFFSET != 0
 #error CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_DATA_PART_OFFSET must be set to 0
 #endif
@@ -104,7 +121,12 @@ struct kwbimage_main_hdr_v1 {
 #ifdef CONFIG_SPL_MMC
 u32 spl_mmc_boot_mode(struct mmc *mmc, const u32 boot_device)
 {
-	return MMCSD_MODE_EMMCBOOT;
+	return IS_SD(mmc) ? MMCSD_MODE_RAW : MMCSD_MODE_EMMCBOOT;
+}
+unsigned long spl_mmc_get_uboot_raw_sector(struct mmc *mmc,
+					   unsigned long raw_sect)
+{
+	return IS_SD(mmc) ? 1 : 0;
 }
 #endif
 
-- 
2.20.1