[PATCH v2 1/2] powerpc/mpic_timer: fix the time is not accurate caused by GTCRR toggle bit
Dongsheng Wang
dongsheng.wang at freescale.com
Mon Jan 6 16:23:30 EST 2014
From: Wang Dongsheng <dongsheng.wang at freescale.com>
When the timer GTCCR toggle bit is inverted, we calculated the rest
of the time is not accurate. So we need to ignore this bit.
Signed-off-by: Wang Dongsheng <dongsheng.wang at freescale.com>
---
v2:
No change.
diff --git a/arch/powerpc/sysdev/mpic_timer.c b/arch/powerpc/sysdev/mpic_timer.c
index 22d7d57..70dcf9c 100644
--- a/arch/powerpc/sysdev/mpic_timer.c
+++ b/arch/powerpc/sysdev/mpic_timer.c
@@ -41,6 +41,7 @@
#define MPIC_TIMER_TCR_ROVR_OFFSET 24
#define TIMER_STOP 0x80000000
+#define GTCCR_TOG 0x80000000
#define TIMERS_PER_GROUP 4
#define MAX_TICKS (~0U >> 1)
#define MAX_TICKS_CASCADE (~0U)
@@ -327,11 +328,13 @@ void mpic_get_remain_time(struct mpic_timer *handle, struct timeval *time)
casc_priv = priv->timer[handle->num].cascade_handle;
if (casc_priv) {
tmp_ticks = in_be32(&priv->regs[handle->num].gtccr);
+ tmp_ticks &= ~GTCCR_TOG;
ticks = ((u64)tmp_ticks & UINT_MAX) * (u64)MAX_TICKS_CASCADE;
tmp_ticks = in_be32(&priv->regs[handle->num - 1].gtccr);
ticks += tmp_ticks;
} else {
ticks = in_be32(&priv->regs[handle->num].gtccr);
+ ticks &= ~GTCCR_TOG;
}
convert_ticks_to_time(priv, ticks, time);
--
1.8.5
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