From: Yuvaraj Kumar C D Date: Wed, 18 Sep 2013 10:11:53 +0000 (+0530) Subject: ARM: exynos: dts: Update 5250 arch timer node with clock frequency X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=4d594dd3028ba8cdfcbd854bde3811a1ee4e36d7;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git ARM: exynos: dts: Update 5250 arch timer node with clock frequency Without the "clock-frequency" property in arch timer node, could able to see the below crash dump. [] (unwind_backtrace+0x0/0xf4) from [] (show_stack+0x10/0x14) [] (show_stack+0x10/0x14) from [] (dump_stack+0x7c/0xb0) [] (dump_stack+0x7c/0xb0) from [] (Ldiv0_64+0x8/0x18) [] (Ldiv0_64+0x8/0x18) from [] (clockevents_config.part.2+0x1c/0x74) [] (clockevents_config.part.2+0x1c/0x74) from [] (clockevents_config_and_register+0x20/0x2c) [] (clockevents_config_and_register+0x20/0x2c) from [] (arch_timer_setup+0xa8/0x134) [] (arch_timer_setup+0xa8/0x134) from [] (arch_timer_init+0x1f4/0x24c) [] (arch_timer_init+0x1f4/0x24c) from [] (clocksource_of_init+0x34/0x58) [] (clocksource_of_init+0x34/0x58) from [] (time_init+0x20/0x2c) [] (time_init+0x20/0x2c) from [] (start_kernel+0x1e0/0x39c) THis is because the Exynos u-boot, for example on the Chromebooks, doesn't set up the CNTFRQ register as expected by arch_timer. Instead, we have to specify the frequency in the device tree like this. Signed-off-by: Yuvaraj Kumar C D [olof: Changed subject, added comment, elaborated on commit message] Signed-off-by: Olof Johansson --- diff --git a/arch/arm/boot/dts/exynos5250.dtsi b/arch/arm/boot/dts/exynos5250.dtsi index 7d7cc777ff7b..bbac42a78ce5 100644 --- a/arch/arm/boot/dts/exynos5250.dtsi +++ b/arch/arm/boot/dts/exynos5250.dtsi @@ -96,6 +96,11 @@ <1 14 0xf08>, <1 11 0xf08>, <1 10 0xf08>; + /* Unfortunately we need this since some versions of U-Boot + * on Exynos don't set the CNTFRQ register, so we need the + * value from DT. + */ + clock-frequency = <24000000>; }; mct@101C0000 {