From 712aa6e24cd624e60d49e520837dab4a7e44faa0 Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Wed, 18 Oct 2023 20:51:59 +0200 Subject: [PATCH] arm: mxs: Clear CPSR V bit to activate low vectors The MXS starts with CPSR V bit set, which makes the CPU jump to high vectors in case of an exception. Those high vectors are located at 0xffff0000, which is where the BootROM exception table is located as well. U-Boot should handle exceptions on its own using its own exception handling code, which is located at 0x0, i.e. at low vectors. Clear the CPSR V bit, so that the CPU would jump to low vectors on exception instead, and therefore run the U-Boot exception handling code. Signed-off-by: Marek Vasut Reviewed-by: Fabio Estevam --- arch/arm/cpu/arm926ejs/mxs/mxs.c | 4 ++++ arch/arm/cpu/arm926ejs/mxs/spl_boot.c | 8 +++++++- 2 files changed, 11 insertions(+), 1 deletion(-) diff --git a/arch/arm/cpu/arm926ejs/mxs/mxs.c b/arch/arm/cpu/arm926ejs/mxs/mxs.c index 6d6166cb83..4f3cb63c56 100644 --- a/arch/arm/cpu/arm926ejs/mxs/mxs.c +++ b/arch/arm/cpu/arm926ejs/mxs/mxs.c @@ -71,6 +71,7 @@ void reset_cpu(void) * actually 0x20, this the associated . Loading the PC * register with an address performs a jump to that address. */ +noinline __attribute__((target("arm"))) void mx28_fixup_vt(uint32_t start_addr) { /* ldr pc, [pc, #0x18] */ @@ -85,6 +86,9 @@ void mx28_fixup_vt(uint32_t start_addr) /* cppcheck-suppress nullPointer */ vt[i + 8] = start_addr + (4 * i); } + + /* Make sure ARM core points to low vectors */ + set_cr(get_cr() & ~CR_V); } #ifdef CONFIG_ARCH_MISC_INIT diff --git a/arch/arm/cpu/arm926ejs/mxs/spl_boot.c b/arch/arm/cpu/arm926ejs/mxs/spl_boot.c index 5e7bdb78be..249f8de8fb 100644 --- a/arch/arm/cpu/arm926ejs/mxs/spl_boot.c +++ b/arch/arm/cpu/arm926ejs/mxs/spl_boot.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include "mxs_init.h" @@ -93,7 +94,9 @@ static uint8_t mxs_get_bootmode_index(void) return i; } -static void mxs_spl_fixup_vectors(void) +static noinline +__attribute__((target("arm"))) +void mxs_spl_fixup_vectors(void) { /* * Copy our vector table to 0x0, since due to HAB, we cannot @@ -104,6 +107,9 @@ static void mxs_spl_fixup_vectors(void) /* cppcheck-suppress nullPointer */ memcpy(0x0, _start, 0x60); + + /* Make sure ARM core points to low vectors */ + set_cr(get_cr() & ~CR_V); } static void mxs_spl_console_init(void) -- 2.39.5