Hi Kukjin, On 01/15/2015 01:02 AM, Daniel Lezcano wrote: > On 01/14/2015 04:51 PM, Kukjin Kim wrote: >> On 01/14/15 14:33, Chanwoo Choi wrote: >> >> Hi, >> >> + Doug, Olof >> >>> This patch adds the support for Exynos 64bit SoC. The delay_timer is only used >>> for Exynos 32bit SoC. >>> >> Yes, the Exynos MCT(Multi-Core Timer) is 64bit timer and it is available >> on 64bit exynos SoC such as exynos7. But basically ARMv8 architecture is >> including ARM ARCH timer (ARM Generic Timer) and exynos7 also has >> implemented it and additionally its access is faster than using memory >> mapped register called SFR for MCT...so Doug submitted patch to use MCT >> on 32bit exynos SoCs before. I know arch_timer. As you comment, ARCH timer would be used for system timer for ARMv8. But, Exynos5433/Exynos7 (ARMv8) include MCT (Multi-Core Timer) IP. I checked it on Exynos5433/EXynos7 User-manaual and tested it. I think that exynos_mct.c should support the Exynos 64-bit SoC because Exynos5433/Exynos7 include already MCT (Multi-Core Timer) IP. Also, I have a problem to verify ARCH timer on Exynos SoC. Exynos User-manual never includes the detailed information about for ARCH timer(e.g, clock for ARCH timer). I knew that I can get the document of ARCH timer for ARM official site but I think it is insufficient to implement ARCH timer on Exynos SoC. Best Regards, Chanwoo Choi >> >> I know using MCT on 64bit exynos is usefulness for Power Management and >> I need to talk to relevant guys in office again. If anything, I'll let >> you know. > > I will wait for your answer before digging more the patch. > > Thanks > -- Daniel > >>> Cc: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> >>> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> >>> Cc: Kukjin Kim <kgene.kim@xxxxxxxxxxx> >>> Cc: Mark Rutland <mark.rutland@xxxxxxx> >>> Signed-off-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx> >>> --- >>> This patch set is tested on 64-bit Exynos SoC. I send only this patch from >>> following patchst[1]. >>> [1] https://lkml.org/lkml/2014/12/2/134 >>> >>> Changes from v2: >>> - None >>> Changes from v1: >>> - Use CONFIG_ARM instead of CONFIG_ARM64 >>> >>> drivers/clocksource/Kconfig | 1 - >>> drivers/clocksource/exynos_mct.c | 4 ++++ >>> 2 files changed, 4 insertions(+), 1 deletion(-) >>> >>> diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig >>> index fc01ec2..be38119 100644 >>> --- a/drivers/clocksource/Kconfig >>> +++ b/drivers/clocksource/Kconfig >>> @@ -135,7 +135,6 @@ config CLKSRC_METAG_GENERIC >>> >>> config CLKSRC_EXYNOS_MCT >>> def_bool y if ARCH_EXYNOS >>> - depends on !ARM64 >>> help >>> Support for Multi Core Timer controller on Exynos SoCs. >>> >>> diff --git a/drivers/clocksource/exynos_mct.c b/drivers/clocksource/exynos_mct.c >>> index 9403061..b840ea1 100644 >>> --- a/drivers/clocksource/exynos_mct.c >>> +++ b/drivers/clocksource/exynos_mct.c >>> @@ -223,6 +223,7 @@ static u64 notrace exynos4_read_sched_clock(void) >>> return exynos4_read_count_32(); >>> } >>> >>> +#if defined(CONFIG_ARM) >>> static struct delay_timer exynos4_delay_timer; >>> >>> static cycles_t exynos4_read_current_timer(void) >>> @@ -231,14 +232,17 @@ static cycles_t exynos4_read_current_timer(void) >>> "cycles_t needs to move to 32-bit for ARM64 usage"); >>> return exynos4_read_count_32(); >>> } >>> +#endif >>> >>> static void __init exynos4_clocksource_init(void) >>> { >>> exynos4_mct_frc_start(); >>> >>> +#if defined(CONFIG_ARM) >>> exynos4_delay_timer.read_current_timer = &exynos4_read_current_timer; >>> exynos4_delay_timer.freq = clk_rate; >>> register_current_timer_delay(&exynos4_delay_timer); >>> +#endif >>> >>> if (clocksource_register_hz(&mct_frc, clk_rate)) >>> panic("%s: can't register clocksource\n", mct_frc.name); > > -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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