Subject: [PATCH v3 1/3] clocksource: davinci: only enable clockevents once tim34 is initialized

From: Bartosz Golaszewski <[email-masked]>
Date: Fri, 10 Jan 2020 18:16:41 +0100

From: Bartosz Golaszewski <[email-masked]>

The DM365 platform has a strange quirk (only present when using ancient
u-boot - mainline u-boot v2013.01 and later works fine) where if we
enable the second half of the timer in periodic mode before we do its
initialization - the time won't start flowing and we can't boot.

When using more recent u-boot, we can enable the timer, then reinitialize
it and all works fine.

To work around this issue only enable clockevents once tim34 is
initialized i.e. move clockevents_config_and_register() below tim34
initialization.

Signed-off-by: Bartosz Golaszewski <[email-masked]>
---
 drivers/clocksource/timer-davinci.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/clocksource/timer-davinci.c b/drivers/clocksource/timer-davinci.c
index 62745c962049..e421946a91c5 100644
--- a/drivers/clocksource/timer-davinci.c
+++ b/drivers/clocksource/timer-davinci.c
@@ -302,10 +302,6 @@ int __init davinci_timer_register(struct clk *clk,
 		return rv;
 	}
 
-	clockevents_config_and_register(&clockevent->dev, tick_rate,
-					DAVINCI_TIMER_MIN_DELTA,
-					DAVINCI_TIMER_MAX_DELTA);
-
 	davinci_clocksource.dev.rating = 300;
 	davinci_clocksource.dev.read = davinci_clocksource_read;
 	davinci_clocksource.dev.mask =
@@ -323,6 +319,10 @@ int __init davinci_timer_register(struct clk *clk,
 		davinci_clocksource_init_tim34(base);
 	}
 
+	clockevents_config_and_register(&clockevent->dev, tick_rate,
+					DAVINCI_TIMER_MIN_DELTA,
+					DAVINCI_TIMER_MAX_DELTA);
+
 	rv = clocksource_register_hz(&davinci_clocksource.dev, tick_rate);
 	if (rv) {
 		pr_err("Unable to register clocksource");
-- 
2.23.0

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