[PATCH 3/3] ARM: OMAP2+: AM43x: Use gptimer as clocksource
Lokesh Vutla
lokeshvutla at ti.com
Thu Feb 6 03:45:48 EST 2014
From: Rajendra Nayak <rnayak at ti.com>
The SyncTimer in AM43x is clocked using the following two sources:
1) An inaccuarte 32k clock (CLK_32KHZ) derived from PER DPLL, causing system
time to go slowly (~10% deviation).
2) external 32KHz RTC clock, which may not always be available on board like
in the case of ePOS EVM
Use gptimer as clocksource instead, as is done in the case of AM335x
(which does not have a SyncTimer). With this, system time keeping works
accurately.
Signed-off-by: Rajendra Nayak <rnayak at ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla at ti.com>
---
arch/arm/mach-omap2/board-generic.c | 2 +-
arch/arm/mach-omap2/timer.c | 3 ++-
2 files changed, 3 insertions(+), 2 deletions(-)
diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c
index 8e3daa1..5679464a 100644
--- a/arch/arm/mach-omap2/board-generic.c
+++ b/arch/arm/mach-omap2/board-generic.c
@@ -229,7 +229,7 @@ DT_MACHINE_START(AM43_DT, "Generic AM43 (Flattened Device Tree)")
.init_late = am43xx_init_late,
.init_irq = omap_gic_of_init,
.init_machine = omap_generic_init,
- .init_time = omap3_sync32k_timer_init,
+ .init_time = omap3_gptimer_timer_init,
.dt_compat = am43_boards_compat,
MACHINE_END
#endif
diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
index 74044aa..b62de9f 100644
--- a/arch/arm/mach-omap2/timer.c
+++ b/arch/arm/mach-omap2/timer.c
@@ -604,7 +604,8 @@ OMAP_SYS_32K_TIMER_INIT(3_secure, 12, "secure_32k_fck", "ti,timer-secure",
2, "timer_sys_ck", NULL);
#endif /* CONFIG_ARCH_OMAP3 */
-#if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_SOC_AM33XX)
+#if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_SOC_AM33XX) || \
+ defined(CONFIG_SOC_AM43XX)
OMAP_SYS_GP_TIMER_INIT(3, 2, "timer_sys_ck", NULL,
1, "timer_sys_ck", "ti,timer-alwon");
#endif
--
1.7.9.5
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