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Diffstat (limited to 'arch/arm64/kernel/traps.c')
-rw-r--r--arch/arm64/kernel/traps.c12
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 9ced1f3f6c48..9ee50ed48132 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -458,11 +458,23 @@ 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;
+
+ if (rt != 31)
+ regs->regs[rt] = read_sysreg(cntfrq_el0);
+ regs->pc += 4;
+}
+
asmlinkage void __exception do_sysinstr(unsigned int esr, struct pt_regs *regs)
{
if ((esr & ESR_ELx_SYS64_ISS_SYS_OP_MASK) == ESR_ELx_SYS64_ISS_SYS_CNTVCT) {
cntvct_read_handler(esr, regs);
return;
+ } else if ((esr & ESR_ELx_SYS64_ISS_SYS_OP_MASK) == ESR_ELx_SYS64_ISS_SYS_CNTFRQ) {
+ cntfrq_read_handler(esr, regs);
+ return;
}
do_undefinstr(regs);