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From d6759902cb467c002086853d2eb38fb969c29f7f Mon Sep 17 00:00:00 2001
From: Rabin Vincent <rabin@rab.in>
Date: Sun, 2 May 2010 15:20:51 +0530
Subject: [PATCH] arm_timer: reload timer when enabled

commit id: d6759902cb467c002086853d2eb38fb969c29f7f in git://git.sv.gnu.org/qemu.git

Reload the timer when TimerControl is written, if the timer is to be
enabled.  Otherwise, if an earlier write to TimerLoad was done while
periodic mode was not set, s->delta may incorrectly still have the value
of the maximum limit instead of the value written to TimerLoad.

This problem is evident on versatileap on current linux-next, which
enables TIMER_CTRL_32BIT before writing to TimerLoad and then enabling
periodic mode and starting the timer.  This causes the first periodic
tick to be scheduled to occur after 0xffffffff periods, leading to a
perceived hang while the kernel waits for the first timer tick.

Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
---
 hw/arm_timer.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/hw/arm_timer.c b/hw/arm_timer.c
index 9fef191..5b6947a 100644
--- a/hw/arm_timer.c
+++ b/hw/arm_timer.c
@@ -113,7 +113,7 @@ static void arm_timer_write(void *opaque, target_phys_addr_t offset,
         case 1: freq >>= 4; break;
         case 2: freq >>= 8; break;
         }
-        arm_timer_recalibrate(s, 0);
+        arm_timer_recalibrate(s, s->control & TIMER_CTRL_ENABLE);
         ptimer_set_freq(s->timer, freq);
         if (s->control & TIMER_CTRL_ENABLE) {
             /* Restart the timer if still enabled.  */
-- 
1.6.5.2

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