[U-Boot] [PATCH 1/7] arm: K3: Avoid use of MCU_PSRAM0 before SYSFW is loaded

[Andrew F. Davis]

On HS devices the 512b region of reset isolated memory called
MCU_PSRAM0 is firewalled by default. Until SYSFW is loaded we
cannot use this memory. It is only used to store a single value
left at the end of SRAM by ROM that will be needed later. Save
that value to a global variable stored in the .data section.
This section is used as .bss will be cleared between saving
this value and using it.

Signed-off-by: Andrew F. Davis <afd at ti.com>
---
 arch/arm/mach-k3/am6_init.c                  | 8 +++-----
 arch/arm/mach-k3/include/mach/am6_hardware.h | 3 ---
 2 files changed, 3 insertions(+), 8 deletions(-)

diff --git a/arch/arm/mach-k3/am6_init.c b/arch/arm/mach-k3/am6_init.c
index a5553190b4..462538e45d 100644
--- a/arch/arm/mach-k3/am6_init.c
+++ b/arch/arm/mach-k3/am6_init.c
@@ -49,11 +49,11 @@ static void ctrl_mmr_unlock(void)
 	mmr_unlock(CTRL_MMR0_BASE, 7);
 }
 
+u32 bootindex __attribute__((section(".data")));
+
 static void store_boot_index_from_rom(void)
 {
-	u32 *boot_index = (u32 *)K3_BOOT_PARAM_TABLE_INDEX_VAL;
-
-	*boot_index = *(u32 *)(CONFIG_SYS_K3_BOOT_PARAM_TABLE_INDEX);
+	bootindex = *(u32 *)(CONFIG_SYS_K3_BOOT_PARAM_TABLE_INDEX);
 }
 
 void board_init_f(ulong dummy)
@@ -94,7 +94,6 @@ u32 spl_boot_mode(const u32 boot_device)
 {
 #if defined(CONFIG_SUPPORT_EMMC_BOOT)
 	u32 devstat = readl(CTRLMMR_MAIN_DEVSTAT);
-	u32 bootindex = readl(K3_BOOT_PARAM_TABLE_INDEX_VAL);
 
 	u32 bootmode = (devstat & CTRLMMR_MAIN_DEVSTAT_BOOTMODE_MASK) >>
 			CTRLMMR_MAIN_DEVSTAT_BOOTMODE_SHIFT;
@@ -170,7 +169,6 @@ static u32 __get_primary_bootmedia(u32 devstat)
 u32 spl_boot_device(void)
 {
 	u32 devstat = readl(CTRLMMR_MAIN_DEVSTAT);
-	u32 bootindex = readl(K3_BOOT_PARAM_TABLE_INDEX_VAL);
 
 	if (bootindex == K3_PRIMARY_BOOTMODE)
 		return __get_primary_bootmedia(devstat);
diff --git a/arch/arm/mach-k3/include/mach/am6_hardware.h b/arch/arm/mach-k3/include/mach/am6_hardware.h
index b5244609af..3343233aa3 100644
--- a/arch/arm/mach-k3/include/mach/am6_hardware.h
+++ b/arch/arm/mach-k3/include/mach/am6_hardware.h
@@ -44,7 +44,4 @@
 #define CTRLMMR_LOCK_KICK1				0x0100c
 #define CTRLMMR_LOCK_KICK1_UNLOCK_VAL			0xd172bc5a
 
-/* MCU SCRATCHPAD usage */
-#define K3_BOOT_PARAM_TABLE_INDEX_VAL	CONFIG_SYS_K3_MCU_SCRATCHPAD_BASE
-
 #endif /* __ASM_ARCH_AM6_HARDWARE_H */
-- 
2.19.1