3 files changed, 22 insertions, 1 deletions

diff --git a/arch/arm/include/asm/arch_timer.h b/arch/arm/include/asm/arch_timer.h
index 92793ba69c40..d4ebf5679f1f 100644
--- a/arch/arm/include/asm/arch_timer.h
+++ b/arch/arm/include/asm/arch_timer.h
@@ -78,6 +78,15 @@ static inline u32 arch_timer_get_cntfrq(void)
         return val;
 }
 
+static inline u64 arch_counter_get_cntpct(void)
+{
+        u64 cval;
+
+        isb();
+        asm volatile("mrrc p15, 0, %Q0, %R0, c14" : "=r" (cval));
+        return cval;
+}
+
 static inline u64 arch_counter_get_cntvct(void)
 {
         u64 cval;
diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h
index f19097134b02..b1fa4e614718 100644
--- a/arch/arm64/include/asm/arch_timer.h
+++ b/arch/arm64/include/asm/arch_timer.h
@@ -104,6 +104,15 @@ static inline void arch_timer_set_cntkctl(u32 cntkctl)
         asm volatile("msr       cntkctl_el1, %0" : : "r" (cntkctl));
 }
 
+static inline u64 arch_counter_get_cntpct(void)
+{
+        /*
+         * AArch64 kernel and user space mandate the use of CNTVCT.
+         */
+        BUG();
+        return 0;
+}
+
 static inline u64 arch_counter_get_cntvct(void)
 {
         u64 cval;
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 2133f9d59d06..55256e4fb641 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -462,7 +462,10 @@ static void __init arch_counter_register(unsigned type)
 
         /* Register the CP15 based counter if we have one */
         if (type & ARCH_CP15_TIMER) {
-                arch_timer_read_counter = arch_counter_get_cntvct;
+                if (arch_timer_use_virtual)
+                        arch_timer_read_counter = arch_counter_get_cntvct;
+                else
+                        arch_timer_read_counter = arch_counter_get_cntpct;
         } else {
                 arch_timer_read_counter = arch_counter_get_cntvct_mem;