[PATCH AUTOSEL 4.19 04/68] MIPS: kernel: only use i8253 clocksource with periodic clockevent

From: Sasha Levin
Date: Tue Aug 13 2019 - 22:33:06 EST


From: Thomas Bogendoerfer <tbogendoerfer@xxxxxxx>

[ Upstream commit a07e3324538a989b7cdbf2c679be6a7f9df2544f ]

i8253 clocksource needs a free running timer. This could only
be used, if i8253 clockevent is set up as periodic.

Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@xxxxxxx>
Signed-off-by: Paul Burton <paul.burton@xxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: James Hogan <jhogan@xxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/mips/kernel/i8253.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/mips/kernel/i8253.c b/arch/mips/kernel/i8253.c
index 5f209f111e59e..df7ddd246eaac 100644
--- a/arch/mips/kernel/i8253.c
+++ b/arch/mips/kernel/i8253.c
@@ -32,7 +32,8 @@ void __init setup_pit_timer(void)

static int __init init_pit_clocksource(void)
{
- if (num_possible_cpus() > 1) /* PIT does not scale! */
+ if (num_possible_cpus() > 1 || /* PIT does not scale! */
+ !clockevent_state_periodic(&i8253_clockevent))
return 0;

return clocksource_i8253_init();
--
2.20.1