powerpc/mpic_timer: fix the time is not accurate caused by GTCRR toggle bit

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@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>

diff --git a/arch/powerpc/sysdev/mpic_timer.c b/arch/powerpc/sysdev/mpic_timer.c
index 22d7d57eead9d88fca57629de658a5629fd2d6bf..70dcf9c5b8fb5fafbfb05191e6411ee629a6b75c 100644 (file)
--- 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);