[PATCH 5.4 304/411] clocksource/drivers/riscv: Events are stopped during CPU suspend

Greg Kroah-Hartman
2022-06-13T11:37:28Z

From: Samuel Holland <samuel@sholland.org>

[ Upstream commit 232ccac1bd9b5bfe73895f527c08623e7fa0752d ]

Some implementations of the SBI time extension depend on hart-local
state (for example, CSRs) that are lost or hardware that is powered
down when a CPU is suspended. To be safe, the clockevents driver
cannot assume that timer IRQs will be received during CPU suspend.

Fixes: 62b019436814 ("clocksource: new RISC-V SBI timer driver")
Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20220509012121.40031-1-samuel@sholland.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/clocksource/timer-riscv.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clocksource/timer-riscv.c b/drivers/clocksource/timer-riscv.c
index 4b04ffbe5e7e..e3be5c2f57b8 100644
--- a/drivers/clocksource/timer-riscv.c
+++ b/drivers/clocksource/timer-riscv.c
@@ -26,7 +26,7 @@ static int riscv_clock_next_event(unsigned long delta,

static DEFINE_PER_CPU(struct clock_event_device, riscv_clock_event) = {
.name = "riscv_timer_clockevent",
- .features = CLOCK_EVT_FEAT_ONESHOT,
+ .features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP,
.rating = 100,
.set_next_event = riscv_clock_next_event,
};
--
2.35.1