Add helper functions to identify different armv8 variants.
Signed-off-by: Peng Fan peng.fan@nxp.com --- arch/arm/include/asm/armv8/cpu.h | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) create mode 100644 arch/arm/include/asm/armv8/cpu.h
diff --git a/arch/arm/include/asm/armv8/cpu.h b/arch/arm/include/asm/armv8/cpu.h new file mode 100644 index 0000000000..40d54dc85a --- /dev/null +++ b/arch/arm/include/asm/armv8/cpu.h @@ -0,0 +1,26 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Copyright 2018 NXP + */ + +#define MIDR_PARTNUM_CORTEX_A35 0xD04 +#define MIDR_PARTNUM_CORTEX_A53 0xD03 +#define MIDR_PARTNUM_CORTEX_A72 0xD08 +#define MIDR_PARTNUM_SHIFT 0x4 +#define MIDR_PARTNUM_MASK (0xFFF << 0x4) + +static inline unsigned int read_midr(void) +{ + unsigned long val; + + asm volatile("mrs %0, midr_el1" : "=r" (val)); + + return val; +} + +#define is_cortex_a35() (((read_midr() & MIDR_PARTNUM_MASK) >> \ + MIDR_PARTNUM_SHIFT) == MIDR_PARTNUM_CORTEX_A35) +#define is_cortex_a53() (((read_midr() & MIDR_PARTNUM_MASK) >> \ + MIDR_PARTNUM_SHIFT) == MIDR_PARTNUM_CORTEX_A53) +#define is_cortex_a72() (((read_midr() & MIDR_PARTNUM_MASK) >>\ + MIDR_PARTNUM_SHIFT) == MIDR_PARTNUM_CORTEX_A72)