[PATCHv5 1/2] clocksource: dw_apb_timer_of: Fix read_sched_clock

[<dinguyen@altera.com>]

From: Dinh Nguyen <dinguyen@altera.com>

The read_sched_clock should return the ~value because the clock is a
countdown implementation. read_sched_clock() should be the same as
 __apbt_read_clocksource().

Signed-off-by: Dinh Nguyen <dinguyen@altera.com>
---
v5: Split up into 2 patches
v4: Simplify the fix by simply returning ~__raw_readl(sched_io_base)
v3: Use APBTMR_N_CURRENT_VALUE define in read_sched_clock()
v2: Maintain backwards compatibility for "dw-apb-timer-sp" and
      "dw-apb-timer-osc".
---
 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 45ba8ae..b29d7cd 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 read_sched_clock(void)
 {
-	return __raw_readl(sched_io_base);
+	return ~__raw_readl(sched_io_base);
 }
 
 static const struct of_device_id sptimer_ids[] __initconst = {
-- 
1.7.9.5