[PATCH v3 1/2] clocksource: arm_arch_timer: Use stable count reader in erratum sne

Keqian Zhu zhukeqian1 at huawei.com
Fri Dec 4 02:31:25 EST 2020


In commit 0ea415390cd3 ("clocksource/arm_arch_timer: Use arch_timer_read_counter
to access stable counters"), we separate stable and normal count reader to omit
unnecessary overhead on systems that have no timer erratum.

However, in erratum_set_next_event_tval_generic(), count reader becomes normal
reader. This converts it to stable reader.

Fixes: 0ea415390cd3 ("clocksource/arm_arch_timer: Use arch_timer_read_counter to access stable counters")
Acked-by: Marc Zyngier <maz at kernel.org>
Signed-off-by: Keqian Zhu <zhukeqian1 at huawei.com>
---
 drivers/clocksource/arm_arch_timer.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 6c3e84180146..777d38cb39b0 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -396,10 +396,10 @@ static void erratum_set_next_event_tval_generic(const int access, unsigned long
 	ctrl &= ~ARCH_TIMER_CTRL_IT_MASK;
 
 	if (access == ARCH_TIMER_PHYS_ACCESS) {
-		cval = evt + arch_counter_get_cntpct();
+		cval = evt + arch_counter_get_cntpct_stable();
 		write_sysreg(cval, cntp_cval_el0);
 	} else {
-		cval = evt + arch_counter_get_cntvct();
+		cval = evt + arch_counter_get_cntvct_stable();
 		write_sysreg(cval, cntv_cval_el0);
 	}
 
-- 
2.23.0




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