Hi Daniel, On 01/19/2015 06:27 PM, Daniel Lezcano wrote: > On 01/19/2015 01:54 AM, Chanwoo Choi wrote: >> Dear Daniel and 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 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. > > Hi Chanwoo, > > [ ... ] > >> Do you have any comment about this patch? > > Yes, a similar patch has been posted for the tegra2 timer to run on arm64. > The patch in question put macros #ifdef CONFIG_ARM64 to disable some parts of > the code. That ended, the tegra2 timer was not needed for the moment because > of the arch timer present, so it has been disabled from the compilation until > a proper fix without macros could be proposed. > > It is happening exactly the same with this patch. As Kukjin pointed it, the > exynos_mct may not be needed (at least until a backup timer is needed at PM > time). > > I suggest you look at a nicer way to fix that instead of introducing macros > (which is by the way valid but not recommended by the CodingStyle rules) and > perhaps sync with Paul and Thierry [cc'ed] to find a common solution.
OK, I understand your opinion. I'll try to consider it without adding '#ifdef'. Best Regards, Chanwoo Choi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
