diff options
| -rw-r--r-- | arch/arm/cpu/armv8/Kconfig | 18 | ||||
| -rw-r--r-- | arch/arm/cpu/armv8/start.S | 11 |
2 files changed, 29 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv8/Kconfig b/arch/arm/cpu/armv8/Kconfig index 22dce88..472b2ba 100644 --- a/arch/arm/cpu/armv8/Kconfig +++ b/arch/arm/cpu/armv8/Kconfig @@ -3,6 +3,24 @@ if ARM64 config ARMV8_MULTIENTRY bool "Enable multiple CPUs to enter into U-Boot" +config ARMV8_SET_SMPEN + bool "Enable data coherency with other cores in cluster" + help + Say Y here if there is not any trust firmware to set + CPUECTLR_EL1.SMPEN bit before U-Boot. + + For A53, it enables data coherency with other cores in the + cluster, and for A57/A72, it enables receiving of instruction + cache and TLB maintenance operations. + Cortex A53/57/72 cores require CPUECTLR_EL1.SMPEN set even + for single core systems. Unfortunately write access to this + register may be controlled by EL3/EL2 firmware. To be more + precise, by default (if there is EL2/EL3 firmware running) + this register is RO for NS EL1. + This switch can be used to avoid writing to CPUECTLR_EL1, + it can be safely enabled when EL2/EL3 initialized SMPEN bit + or when CPU implementation doesn't include that register. + config ARMV8_SPIN_TABLE bool "Support spin-table enable method" depends on ARMV8_MULTIENTRY && OF_LIBFDT diff --git a/arch/arm/cpu/armv8/start.S b/arch/arm/cpu/armv8/start.S index 4f5f6d8..5308702 100644 --- a/arch/arm/cpu/armv8/start.S +++ b/arch/arm/cpu/armv8/start.S @@ -86,6 +86,17 @@ save_boot_params_ret: msr cpacr_el1, x0 /* Enable FP/SIMD */ 0: + /* + * Enalbe SMPEN bit for coherency. + * This register is not architectural but at the moment + * this bit should be set for A53/A57/A72. + */ +#ifdef CONFIG_ARMV8_SET_SMPEN + mrs x0, S3_1_c15_c2_1 /* cpuactlr_el1 */ + orr x0, x0, #0x40 + msr S3_1_c15_c2_1, x0 +#endif + /* Apply ARM core specific erratas */ bl apply_core_errata |