From 8dfa741f146b39eb59ef2094e03f47079ca99eb0 Mon Sep 17 00:00:00 2001 From: Ralf Baechle <ralf@linux-mips.org> Date: Sun, 11 Nov 2007 17:33:55 +0000 Subject: [PATCH] [MIPS] Sibyte: Stop timers before programming next even. We have no guarantee by the generic time code that the timer is stopped when the ->next_event method is called. Modifying the Timer Initial Count register while the timer is enabled has UNPREDICTABLE effect according to the BCM1250/BCM1125/BCM1125H User Manual. So stop the timer before reprogramming. This is a paranoia fix; no ill effects have been observed previously. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> --- arch/mips/kernel/cevt-bcm1480.c | 1 + arch/mips/kernel/cevt-sb1250.c | 1 + 2 files changed, 2 insertions(+) diff --git a/arch/mips/kernel/cevt-bcm1480.c b/arch/mips/kernel/cevt-bcm1480.c index e54410e5a2cd..0a57f86945f1 100644 --- a/arch/mips/kernel/cevt-bcm1480.c +++ b/arch/mips/kernel/cevt-bcm1480.c @@ -75,6 +75,7 @@ static int sibyte_next_event(unsigned long delta, struct clock_event_device *cd) cfg = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG)); init = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_INIT)); + __raw_writeq(0, cfg); __raw_writeq(delta - 1, init); __raw_writeq(M_SCD_TIMER_ENABLE, cfg); diff --git a/arch/mips/kernel/cevt-sb1250.c b/arch/mips/kernel/cevt-sb1250.c index 8fbb05537680..63ac3ad462bc 100644 --- a/arch/mips/kernel/cevt-sb1250.c +++ b/arch/mips/kernel/cevt-sb1250.c @@ -73,6 +73,7 @@ static int sibyte_next_event(unsigned long delta, struct clock_event_device *cd) cfg = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG)); init = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_INIT)); + __raw_writeq(0, cfg); __raw_writeq(delta - 1, init); __raw_writeq(M_SCD_TIMER_ENABLE, cfg); -- GitLab