Provide a option to allow Endian at U-Boot's EL to be setted
at reset entry.
Signed-off-by: Jiaxun Yang <jiaxun.y...@flygoat.com>
---
arch/arm/cpu/armv8/Kconfig | 9 +++++++++
arch/arm/cpu/armv8/start.S | 26 ++++++++++++++++++++++++++
2 files changed, 35 insertions(+)
diff --git a/arch/arm/cpu/armv8/Kconfig b/arch/arm/cpu/armv8/Kconfig
index 9f0fb369f773..4b38ee12de58 100644
--- a/arch/arm/cpu/armv8/Kconfig
+++ b/arch/arm/cpu/armv8/Kconfig
@@ -14,6 +14,15 @@ config ARMV8_SPL_EXCEPTION_VECTORS
Say N here if you are running out of code space in the image
and want to save some space at the cost of less debugging info.
+config ARMV8_RESET_SET_ENDIAN
+ bool "Set CPU endianness at reset entry"
+ help
+ Perform endianness setting with SCTLR_ELx registers at U-Boot's
+ reset entry.
+
+ Say Y here if your CPU may comes out of reset in a different
+ endianness.
+
config ARMV8_MULTIENTRY
bool "Enable multiple CPUs to enter into U-Boot"
diff --git a/arch/arm/cpu/armv8/start.S b/arch/arm/cpu/armv8/start.S
index 746128026172..2e6ae2f6f3ca 100644
--- a/arch/arm/cpu/armv8/start.S
+++ b/arch/arm/cpu/armv8/start.S
@@ -9,6 +9,7 @@
#include <linux/linkage.h>
#include <asm/macro.h>
#include <asm/armv8/mmu.h>
+#include <asm/assembler.h>
/*************************************************************************
*
@@ -53,6 +54,31 @@ _bss_end_ofs:
.quad __bss_end - _start
reset:
+#if CONFIG_IS_ENABLED(ARMV8_RESET_SET_ENDIAN)
+ switch_el x16, 3f, 2f, 1f
+3: mrs x16, sctlr_el3
+CPU_BE( mov x17, #(CR_EE))
+CPU_BE( orr x16, x17, x16)
+CPU_LE( mov x17, #~(CR_EE))
+CPU_LE( and x16, x17, x16)
+ msr sctlr_el3, x16
+ isb
+2: mrs x16, sctlr_el2
+CPU_BE( mov x17, #(CR_EE | CR_E0E))
+CPU_BE( orr x16, x17, x16)
+CPU_LE( mov x17, #~(CR_EE | CR_E0E))
+CPU_LE( and x16, x17, x16)
+ msr sctlr_el2, x16
+ isb
+1: mrs x16, sctlr_el1
+CPU_BE( mov x17, #(CR_EE | CR_E0E))
+CPU_BE( orr x16, x17, x16)
+CPU_LE( mov x17, #~(CR_EE | CR_E0E))
+CPU_LE( and x16, x17, x16)
+ msr sctlr_el1, x16
+0: isb
+#endif
+
/* Allow the board to save important registers */
b save_boot_params
.globl save_boot_params_ret
--
2.43.0
