From: Grygorii Strashko Date: Mon, 5 Dec 2016 03:57:44 +0000 (+0530) Subject: ARM: omap2+: am437x: rollback to use omap3_gptimer_timer_init() X-Git-Tag: v4.14-rc1~1671^2~1^2~19 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=f86a2c875fd146d9b82c8fdd86d31084507bcf4c;p=platform%2Fkernel%2Flinux-rpi3.git ARM: omap2+: am437x: rollback to use omap3_gptimer_timer_init() The commit 55ee7017ee31 ("arm: omap2: board-generic: use omap4_local_timer_init for AM437x") unintentionally changes the clocksource devices for AM437x from OMAP GP Timer to SyncTimer32K. Unfortunately, the SyncTimer32K is starving from frequency deviation as mentioned in commit 5b5c01359152 ("ARM: OMAP2+: AM43x: Use gptimer as clocksource") and, as reported by Franklin [1], even its monotonic nature is under question (most probably there is a HW issue, but it's still under investigation). Taking into account above facts It's reasonable to rollback to the use of omap3_gptimer_timer_init(). [1] http://www.spinics.net/lists/linux-omap/msg127425.html Fixes: 55ee7017ee31 ("arm: omap2: board-generic: use omap4_local_timer_init for AM437x") Reported-by: Cooper Jr., Franklin Signed-off-by: Grygorii Strashko Signed-off-by: Lokesh Vutla Signed-off-by: Keerthy Signed-off-by: Tony Lindgren --- diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c index 36d9943..dc9e34e 100644 --- a/arch/arm/mach-omap2/board-generic.c +++ b/arch/arm/mach-omap2/board-generic.c @@ -304,7 +304,7 @@ 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 = omap4_local_timer_init, + .init_time = omap3_gptimer_timer_init, .dt_compat = am43_boards_compat, .restart = omap44xx_restart, MACHINE_END diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c index 56128da..07dd692 100644 --- a/arch/arm/mach-omap2/timer.c +++ b/arch/arm/mach-omap2/timer.c @@ -510,18 +510,19 @@ void __init omap3_secure_sync32k_timer_init(void) } #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) void __init omap3_gptimer_timer_init(void) { __omap_sync32k_timer_init(2, "timer_sys_ck", NULL, 1, "timer_sys_ck", "ti,timer-alwon", true); - - clocksource_probe(); + if (of_have_populated_dt()) + clocksource_probe(); } #endif #if defined(CONFIG_ARCH_OMAP4) || defined(CONFIG_SOC_OMAP5) || \ - defined(CONFIG_SOC_DRA7XX) || defined(CONFIG_SOC_AM43XX) + defined(CONFIG_SOC_DRA7XX) static void __init omap4_sync32k_timer_init(void) { __omap_sync32k_timer_init(1, "timer_32k_ck", "ti,timer-alwon",