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 <[e-mail]>
Signed-off-by: Daniel Lezcano <[e-mail]>
Acked-by: Nicolas Ferre <[e-mail]>
Cc: Dinh Nguyen <[e-mail]>
Cc: Linux ARM Kernel <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Ingo Molnar <[e-mail]>

drivers/clocksource/dw_apb_timer_of.c

···
 
 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 = {