From 31c6c79a01c05dca9ab93b42f0f97d973a4db61f Mon Sep 17 00:00:00 2001
From: Eduard Strehlau <eduard@lionizers.com>
Date: Wed, 26 Apr 2023 13:04:54 -0300
Subject: [PATCH] smegw01: Enable EMMC boot from multiple partitions

GPT Partition labels are used for determining the right
root filesystem to boot from.

The U-Boot environment is configured to reside in the eMMC hardware
boot partition we are currently booted from.

This should enable a dual copy approach for upgrading the bootloader.
One can overwrite the inactive hardware partition with new bootloader
and environment and afterwards switch the eMMC boot partition for an
atomic bootloader switch.

Signed-off-by: Eduard Strehlau <eduard@lionizers.com>
Signed-off-by: Fabio Estevam <festevam@denx.de>
---
 board/storopack/smegw01/smegw01.c | 10 ++++++++++
 configs/smegw01_defconfig         |  2 ++
 include/configs/smegw01.h         | 12 ++++++++----
 3 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/board/storopack/smegw01/smegw01.c b/board/storopack/smegw01/smegw01.c
index e6bff80..7d4de93 100644
--- a/board/storopack/smegw01/smegw01.c
+++ b/board/storopack/smegw01/smegw01.c
@@ -17,6 +17,7 @@
 #include <asm/arch/crm_regs.h>
 #include <asm/setup.h>
 #include <asm/bootm.h>
+#include <mmc.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -93,3 +94,12 @@ int board_late_init(void)
 
 	return 0;
 }
+
+uint board_mmc_get_env_part(struct mmc *mmc)
+{
+	uint part = EXT_CSD_EXTRACT_BOOT_PART(mmc->part_config);
+
+	if (part == 7)
+		part = 0;
+	return part;
+}
diff --git a/configs/smegw01_defconfig b/configs/smegw01_defconfig
index b3580d5..54cf1cf 100644
--- a/configs/smegw01_defconfig
+++ b/configs/smegw01_defconfig
@@ -30,6 +30,7 @@ CONFIG_CMD_MEMTEST=y
 CONFIG_CMD_UNZIP=y
 CONFIG_CMD_DFU=y
 CONFIG_CMD_GPIO=y
+CONFIG_CMD_GPT=y
 CONFIG_CMD_MMC=y
 CONFIG_CMD_PART=y
 CONFIG_CMD_DHCP=y
@@ -44,6 +45,7 @@ CONFIG_OF_CONTROL=y
 CONFIG_ENV_OVERWRITE=y
 CONFIG_SYS_REDUNDAND_ENVIRONMENT=y
 CONFIG_SYS_RELOC_GD_ENV_ADDR=y
+CONFIG_SYS_MMC_ENV_DEV=1
 CONFIG_NET_RANDOM_ETHADDR=y
 CONFIG_BOUNCE_BUFFER=y
 CONFIG_BOOTCOUNT_LIMIT=y
diff --git a/include/configs/smegw01.h b/include/configs/smegw01.h
index 277c828..71f2d9c 100644
--- a/include/configs/smegw01.h
+++ b/include/configs/smegw01.h
@@ -32,17 +32,21 @@
 	"mmcpart=1\0" \
 	"mmcpart_committed=1\0" \
 	"mmcargs=setenv bootargs console=${console},${baudrate} " \
-		"root=/dev/mmcblk0p${mmcpart_committed} rootwait rw " \
-		__stringify(EXTRA_BOOTPARAMS) "\0" \
+		"root=/dev/mmcblk${mmcdev}p${gpt_partition_entry} rootwait rw " \
+		__stringify(EXTRA_BOOTPARAMS) " SM_ROOT_DEV=${mmcdev} SM_ROOT_PART=${gpt_partition_entry} SM_BOOT_PART=${boot_part}\0" \
 	"commit_mmc=if test \"${ustate}\" = 1 -a \"${mmcpart}\" != \"${mmcpart_committed}\"; then " \
 	              "setenv mmcpart_committed ${mmcpart};" \
 								"saveenv;" \
 						  "fi;\0" \
 	"bootlimit=3\0" \
-	"loadimage=load mmc ${mmcdev}:${mmcpart_committed} ${loadaddr} boot/${image}\0" \
-	"loadfdt=load mmc ${mmcdev}:${mmcpart_committed} ${fdt_addr} boot/${fdtfile}\0" \
+	"loadimage=load mmc ${mmcdev}#rootfs-${mmcpart_committed} ${loadaddr} boot/${image}\0" \
+	"loadfdt=load mmc ${mmcdev}#rootfs-${mmcpart_committed} ${fdt_addr} boot/${fdtfile}\0" \
+	"loadpart=gpt setenv mmc ${mmcdev} rootfs-${mmcpart_committed}\0" \
+	"loadbootpart=mmc partconf 1 boot_part\0" \
 	"mmcboot=echo Booting from mmc ...; " \
 	  "run commit_mmc; " \
+		"run loadpart; " \
+		"run loadbootpart; " \
 		"run mmcargs; " \
 		"if run loadfdt; then " \
 			"if bootz ${loadaddr} - ${fdt_addr}; then " \
-- 
2.7.4