[PATCH V2 4/4] ARM: OMAP2+: AM43x: Use gptimer as clocksource

[Lokesh Vutla]

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