[tip:timers/core] clocksource/drivers/dw_apb_timers_of: Fix IO endianness causing time jumps

[tip-bot for Ben Dooks]

Commit-ID:  3a10013b6a5975346fe5a8db59500a8d176d64e0
Gitweb:     http://git.kernel.org/tip/3a10013b6a5975346fe5a8db59500a8d176d64e0
Author:     Ben Dooks <ben.dooks@xxxxxxxxxxxxxxx>
AuthorDate: Mon, 30 Mar 2015 22:17:12 +0200
Committer:  Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Tue, 31 Mar 2015 09:15:57 +0200

clocksource/drivers/dw_apb_timers_of: Fix IO endianness causing time jumps

The dw_apb_timer_of timer is using __raw_readl() to access the
timer register, which is causing issues when the system is
running in big endian mode. Fix this by using readl_relaxed()
which should account for the endian settings.

This fixes issues where the time jumps around in the dmesg
output due to returnling __le32 values.

For an example, these two console lines show time running
backwards:

[   49.882572] CPU1: failed to come online
[   43.282457] Brought up 1 CPUs

Signed-off-by: Ben Dooks <ben.dooks@xxxxxxxxxxxxxxx>
Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
Acked-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxx>
Cc: Dinh Nguyen <dinguyen@xxxxxxxxxxxxxxxxxxxxx>
Cc: Linux ARM Kernel <linux-arm-kernel@xxxxxxxxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: digetx@xxxxxxxxx
Cc: hdegoede@xxxxxxxxxx
Cc: laurent.pinchart+renesas@xxxxxxxxxxxxxxxx
Cc: maxime.ripard@xxxxxxxxxxxxxxxxxx
Cc: viresh.kumar@xxxxxxxxxx
Link: http://lkml.kernel.org/r/1427746633-9137-10-git-send-email-daniel.lezcano@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 drivers/clocksource/dw_apb_timer_of.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clocksource/dw_apb_timer_of.c b/drivers/clocksource/dw_apb_timer_of.c
index d305fb0..a19a3f6 100644
--- a/drivers/clocksource/dw_apb_timer_of.c
+++ b/drivers/clocksource/dw_apb_timer_of.c
@@ -108,7 +108,7 @@ static void __init add_clocksource(struct device_node *source_timer)
 
 static u64 notrace read_sched_clock(void)
 {
-	return ~__raw_readl(sched_io_base);
+	return ~readl_relaxed(sched_io_base);
 }
 
 static const struct of_device_id sptimer_ids[] __initconst = {
--
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