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sun4i-timer: Only register a sched_clock on sun4i and sun5i

PATCH New Hans de Goede 2 participants 2 messages Mar 21, 2015 – Mar 22, 2015

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Arm/Allwinner sunXi SoC support Clocksource, clockevent drivers
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Hans de Goede

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#0 lore raw

PATCH 1/1 sun4i-timer: Only register a sched_clock on sun4i and sun5i

sun6i and newer have an arm arch timer which is a better sched_clock source then the sun4i-timer, and sched_clock does not have priorities, so do not register the sun4i-timer sched_clock at all on sun6i and newer.

Signed-off-by Hans de Goede <[email protected]>
---
 drivers/clocksource/sun4i_timer.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)
drivers/clocksource/sun4i_timer.c +9 -1
index f4a9c00..1928a89 100644
@@ -170,7 +170,15 @@ static void __init sun4i_timer_init(struct device_node *node)
 	       TIMER_CTL_CLK_SRC(TIMER_CTL_CLK_SRC_OSC24M),
 	       timer_base + TIMER_CTL_REG(1));
 
-	sched_clock_register(sun4i_timer_sched_read, 32, rate);
+	/*
+	 * sched_clock_register does not have priorities, and on sun6i and
+	 * later there is a better sched_clock registered by arm_arch_timer.c
+	 */
+	if (of_machine_is_compatible("allwinner,sun4i-a10") ||
+	    of_machine_is_compatible("allwinner,sun5i-a13") ||
+	    of_machine_is_compatible("allwinner,sun5i-a10s"))
+		sched_clock_register(sun4i_timer_sched_read, 32, rate);
+
 	clocksource_mmio_init(timer_base + TIMER_CNTVAL_REG(1), node->name,
 			      rate, 350, 32, clocksource_mmio_readl_down);
Signature · 1 line
2.3.3
#1 lore raw

PATCH 1/1 sun4i-timer: Only register a sched_clock on sun4i and sun5i

Quoted 5 lines · Hans de Goede

sun6i and newer have an arm arch timer which is a better sched_clock source then the sun4i-timer, and sched_clock does not have priorities, so do not register the sun4i-timer sched_clock at all on sun6i and newer.

Signed-off-by Hans de Goede <[email protected]>
Acked-by Maxime Ripard <[email protected]>

Thanks!

Signature · 10 lines
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
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