When TF-A hands over control to Armv8 SPL/U-boot in K3 architecture, by default, the SERROR[1] is not trapped in EL2/1 - this allows bootloaders and hypervisors to make specific choices as to what they would like to do.

However the side effect of this design choice is that if TF-A does'nt trap exceptions in EL3, exceptions created by SPL/U-boot is only trapped when kernel gets started, and that too at a very late stage.

Instead, lets try and follow the model that layerscape and imx follows and enable the same in u-boot itself.

NOTE: While, theoretically, it is possible to enable the exceptions very early in the boot process (say, low_level_init) there is hardly any interactions taking place until board_init_f, making the integration relatively easier.

[1] https://developer.arm.com/documentation/100933/0100/Synchronous-and-asynchro...

Inspired-by: Andre Przywara andre.przywara@arm.com Link: https://patchwork.ozlabs.org/project/uboot/cover/20200117012047.31096-1-andr... Signed-off-by: Nishanth Menon nm@ti.com ---

This patch is RFC based on the discussion https://libera.irclog.whitequark.org/u-boot/2022-01-07 This is armv8 architecture implementation detail, that is better done in arch/arm/cpu/armv8 in a generic manner - just a patch to indicate the problem is wide spread and to support the efforts of Andre to fix this up. In the meanwhile, for others in K3 community looking for an intermediate fixup.

Thanks Andre for helping clean this up.

arch/arm/mach-k3/Makefile | 1 + arch/arm/mach-k3/am642_init.c | 2 ++ arch/arm/mach-k3/am6_init.c | 2 ++ arch/arm/mach-k3/arm64-misc.S | 21 +++++++++++++++++++++ arch/arm/mach-k3/common.h | 1 + arch/arm/mach-k3/include/mach/hardware.h | 1 - arch/arm/mach-k3/j721e_init.c | 2 ++ 7 files changed, 29 insertions(+), 1 deletion(-) create mode 100644 arch/arm/mach-k3/arm64-misc.S

diff --git a/arch/arm/mach-k3/Makefile b/arch/arm/mach-k3/Makefile index b965848e2350..213bf684802b 100644 --- a/arch/arm/mach-k3/Makefile +++ b/arch/arm/mach-k3/Makefile @@ -11,6 +11,7 @@ obj-$(CONFIG_ARM64) += arm64-mmu.o obj-$(CONFIG_CPU_V7R) += r5_mpu.o lowlevel_init.o obj-$(CONFIG_TI_SECURE_DEVICE) += security.o obj-$(CONFIG_ARM64) += cache.o +obj-$(CONFIG_ARM64) += arm64-misc.o ifeq ($(CONFIG_SPL_BUILD),y) obj-$(CONFIG_K3_LOAD_SYSFW) += sysfw-loader.o endif diff --git a/arch/arm/mach-k3/am642_init.c b/arch/arm/mach-k3/am642_init.c index 533905daeb41..402b4219e16e 100644 --- a/arch/arm/mach-k3/am642_init.c +++ b/arch/arm/mach-k3/am642_init.c @@ -148,6 +148,8 @@ void board_init_f(ulong dummy)

#if defined(CONFIG_CPU_V7R) setup_k3_mpu_regions(); +#else + __asm_k3_enable_serror(); #endif

/* diff --git a/arch/arm/mach-k3/am6_init.c b/arch/arm/mach-k3/am6_init.c index ffb7aaded2e7..15b1fa4cc022 100644 --- a/arch/arm/mach-k3/am6_init.c +++ b/arch/arm/mach-k3/am6_init.c @@ -186,6 +186,8 @@ void board_init_f(ulong dummy) #ifdef CONFIG_CPU_V7R disable_linefill_optimization(); setup_k3_mpu_regions(); +#else + __asm_k3_enable_serror(); #endif

/* Init DM early in-order to invoke system controller */ diff --git a/arch/arm/mach-k3/arm64-misc.S b/arch/arm/mach-k3/arm64-misc.S new file mode 100644 index 000000000000..86b9481fc0e4 --- /dev/null +++ b/arch/arm/mach-k3/arm64-misc.S @@ -0,0 +1,21 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2022 Texas Instruments Incorporated - http://www.ti.com/ + */ + +#include <config.h> +#include <linux/linkage.h> + +#if defined(CONFIG_SPL_BUILD) +ENTRY(__asm_k3_enable_serror) + /* unmask SError and abort */ + msr daifclr, #4 + + /* Set HCR_EL2[AMO] so SError @EL2 is taken */ + mrs x0, hcr_el2 + orr x0, x0, #0x20 /* AMO */ + msr hcr_el2, x0 + isb + ret +ENDPROC(__asm_k3_enable_serror) +#endif diff --git a/arch/arm/mach-k3/common.h b/arch/arm/mach-k3/common.h index e81b70d7c368..2680a21af344 100644 --- a/arch/arm/mach-k3/common.h +++ b/arch/arm/mach-k3/common.h @@ -19,6 +19,7 @@ struct fwl_data { };

void setup_k3_mpu_regions(void); +void __asm_k3_enable_serror(void); int early_console_init(void); void disable_linefill_optimization(void); void remove_fwl_configs(struct fwl_data *fwl_data, size_t fwl_data_size); diff --git a/arch/arm/mach-k3/include/mach/hardware.h b/arch/arm/mach-k3/include/mach/hardware.h index e87a888465c1..bb874d4e0638 100644 --- a/arch/arm/mach-k3/include/mach/hardware.h +++ b/arch/arm/mach-k3/include/mach/hardware.h @@ -35,5 +35,4 @@ struct rom_extended_boot_data { char header[8]; u32 num_components; }; - #endif /* _ASM_ARCH_HARDWARE_H_ */ diff --git a/arch/arm/mach-k3/j721e_init.c b/arch/arm/mach-k3/j721e_init.c index 78d80be1758e..84513bca8869 100644 --- a/arch/arm/mach-k3/j721e_init.c +++ b/arch/arm/mach-k3/j721e_init.c @@ -153,6 +153,8 @@ void board_init_f(ulong dummy) #ifdef CONFIG_CPU_V7R disable_linefill_optimization(); setup_k3_mpu_regions(); +#else + __asm_k3_enable_serror(); #endif

/* Init DM early */