[PATCH 2/3] clocksource/drivers/timer-clint: Add set_state_shutdown

From: Jisheng Zhang
Date: Wed Mar 27 2024 - 11:50:07 EST


Add clocksource detach/shutdown callback to disable RISC-V timer interrupt when
switching out clockevent from clint timer to another timer.

Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxx>
---
drivers/clocksource/timer-clint.c | 18 ++++++++++++++----
1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/clocksource/timer-clint.c b/drivers/clocksource/timer-clint.c
index 09fd292eb83d..56cf6c672e6d 100644
--- a/drivers/clocksource/timer-clint.c
+++ b/drivers/clocksource/timer-clint.c
@@ -119,11 +119,21 @@ static int clint_clock_next_event(unsigned long delta,
return 0;
}

+static int clint_clock_shutdown(struct clock_event_device *evt)
+{
+ void __iomem *r = clint_timer_cmp +
+ cpuid_to_hartid_map(smp_processor_id());
+
+ writeq_relaxed(ULONG_MAX, r);
+ return 0;
+}
+
static DEFINE_PER_CPU(struct clock_event_device, clint_clock_event) = {
- .name = "clint_clockevent",
- .features = CLOCK_EVT_FEAT_ONESHOT,
- .rating = 100,
- .set_next_event = clint_clock_next_event,
+ .name = "clint_clockevent",
+ .features = CLOCK_EVT_FEAT_ONESHOT,
+ .rating = 100,
+ .set_next_event = clint_clock_next_event,
+ .set_state_shutdown = clint_clock_shutdown,
};

static int clint_timer_starting_cpu(unsigned int cpu)
--
2.43.0