diff --git a/arch/arm64/include/asm/esr.h b/arch/arm64/include/asm/esr.h index ad42e79a5d4d4..85997c0e54431 100644 --- a/arch/arm64/include/asm/esr.h +++ b/arch/arm64/include/asm/esr.h @@ -177,6 +177,10 @@ #define ESR_ELx_SYS64_ISS_SYS_CNTVCT (ESR_ELx_SYS64_ISS_SYS_VAL(3, 3, 2, 14, 0) | \ ESR_ELx_SYS64_ISS_DIR_READ) + +#define ESR_ELx_SYS64_ISS_SYS_CNTFRQ (ESR_ELx_SYS64_ISS_SYS_VAL(3, 3, 0, 14, 0) | \ + ESR_ELx_SYS64_ISS_DIR_READ) + #ifndef __ASSEMBLY__ #include diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index 1de444e6c6697..d4d6ae02cd558 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -513,6 +513,14 @@ static void cntvct_read_handler(unsigned int esr, struct pt_regs *regs) regs->pc += 4; } +static void cntfrq_read_handler(unsigned int esr, struct pt_regs *regs) +{ + int rt = (esr & ESR_ELx_SYS64_ISS_RT_MASK) >> ESR_ELx_SYS64_ISS_RT_SHIFT; + + pt_regs_write_reg(regs, rt, read_sysreg(cntfrq_el0)); + regs->pc += 4; +} + struct sys64_hook { unsigned int esr_mask; unsigned int esr_val; @@ -537,6 +545,12 @@ static struct sys64_hook sys64_hooks[] = { .esr_val = ESR_ELx_SYS64_ISS_SYS_CNTVCT, .handler = cntvct_read_handler, }, + { + /* Trap read access to CNTFRQ_EL0 */ + .esr_mask = ESR_ELx_SYS64_ISS_SYS_OP_MASK, + .esr_val = ESR_ELx_SYS64_ISS_SYS_CNTFRQ, + .handler = cntfrq_read_handler, + }, {}, };