From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965021AbaE3OoA (ORCPT ); Fri, 30 May 2014 10:44:00 -0400 Received: from mailout1.w1.samsung.com ([210.118.77.11]:20308 "EHLO mailout1.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933023AbaE3On6 (ORCPT ); Fri, 30 May 2014 10:43:58 -0400 MIME-version: 1.0 Content-type: text/plain; charset=UTF-8 X-AuditID: cbfec7f4-b7fac6d000006cfe-2f-5388992a2138 Content-transfer-encoding: 8BIT Message-id: <1401461039.11651.6.camel@AMDC1943> Subject: Re: [PATCH] ARM: exynos4212: hotplug: Fix CPU idle clock down after CPU1 off From: Krzysztof Kozlowski To: Tomasz Figa Cc: Russell King , Kukjin Kim , linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, Kyungmin Park , Marek Szyprowski , Bartlomiej Zolnierkiewicz , Tomasz Figa Date: Fri, 30 May 2014 16:43:59 +0200 In-reply-to: <53888008.5020108@gmail.com> References: <1399990378-7023-1-git-send-email-k.kozlowski@samsung.com> <53887095.7090108@gmail.com> <1401453990.11651.2.camel@AMDC1943> <53888008.5020108@gmail.com> X-Mailer: Evolution 3.10.4-0ubuntu1 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFjrFLMWRmVeSWpSXmKPExsVy+t/xK7paMzuCDWZPkbPYOGM9q0Xvgqts Fmeb3rBbbHp8jdXi8q45bBYzzu9jsrh9mddi7ZG77BbrZ7xmsVi16w+jA5dHS3MPm8fOWXfZ PTYvqffo27KK0ePzJrkA1igum5TUnMyy1CJ9uwSujHct29gKzkhVvN3fx9TA2CfaxcjBISFg IvH4VFUXIyeQKSZx4d56ti5GLg4hgaWMErf+d7OBJHgFBCV+TL7HAlLPLCAvceRSNkiYWUBd YtK8RcwQ9Z8ZJa41LoSq15c4seoLO4gtLBAu8XbJTUYQm03AWGLz8iVgNSJAzd+m9LODNDML vGOSeDrpLQtIgkVAVWLnw0dgDZwCmhLz23uhNqxglOjd/4AV4lRliXn7jzFNYBSYheTAWQgH zkJy4AJG5lWMoqmlyQXFSem5hnrFibnFpXnpesn5uZsYIeH/ZQfj4mNWhxgFOBiVeHgzXdqD hVgTy4orcw8xSnAwK4nwOvR2BAvxpiRWVqUW5ccXleakFh9iZOLglGpgLFF90PYvLf/NlnvL /m//oue9/9p1Z9tjCy/bvahYGfFsp5CF1M2Gjq9Zm8yac7+ueLJtlvu9Er9f6lYXc3IinXYH S6+2tte7tJj5opzpj03LVQODsz/PFhKutezfMCst+cekAHOTvUHvHwEjd90s11c/q1dtNe3/ +l0k4YZnv820hv0PrhqXK7EUZyQaajEXFScCAHA/ArJdAgAA Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On pią, 2014-05-30 at 14:56 +0200, Tomasz Figa wrote: > On 30.05.2014 14:46, Krzysztof Kozlowski wrote: > > On pią, 2014-05-30 at 13:50 +0200, Tomasz Figa wrote: > >> Hi Krzysztof, > >> > >> On 13.05.2014 16:12, Krzysztof Kozlowski wrote: > >>> On Exynos4212 USE_DELAYED_RESET_ASSERTION must be set in > >>> ARM_CORE1_OPTION register during CPU power down. This is the proper way > >>> of powering down CPU. Additionally without this the CPU clock down won't > >>> work after powering down CPU1 and CPU will work at full frequency chosen > >>> by CPUfreq governor. > >>> > >>> Signed-off-by: Krzysztof Kozlowski > >>> --- > >>> arch/arm/mach-exynos/hotplug.c | 28 +++++++++++++++++++++++++--- > >>> arch/arm/mach-exynos/regs-pmu.h | 2 ++ > >>> 2 files changed, 27 insertions(+), 3 deletions(-) > >>> > >>> diff --git a/arch/arm/mach-exynos/hotplug.c b/arch/arm/mach-exynos/hotplug.c > >>> index 5eead530c6f8..59b813e74558 100644 > >>> --- a/arch/arm/mach-exynos/hotplug.c > >>> +++ b/arch/arm/mach-exynos/hotplug.c > >>> @@ -74,7 +74,7 @@ static inline void cpu_enter_lowpower_a15(void) > >>> dsb(); > >>> } > >>> > >>> -static inline void cpu_leave_lowpower(void) > >>> +static inline void cpu_leave_lowpower(unsigned int cpu) > >>> { > >>> unsigned int v; > >>> > >>> @@ -88,6 +88,14 @@ static inline void cpu_leave_lowpower(void) > >>> : "=&r" (v) > >>> : "Ir" (CR_C), "Ir" (0x40) > >>> : "cc"); > >>> + > >>> + if (cpu == 1 && soc_is_exynos4212()) { > >> > >> AFAIK this is needed not only on Exynos4x12, but at least also on 4412. > >> Also I don't think the (cpu == 1) condition is necessary. See below. > > > > I'll test it on Exynos4412. > > > >> > >>> + unsigned int tmp; > >>> + > >>> + tmp = __raw_readl(S5P_ARM_CORE1_OPTION); > >>> + tmp &= ~(S5P_USE_DELAYED_RESET_ASSERTION); > >>> + __raw_writel(tmp, S5P_ARM_CORE1_OPTION); > >>> + } > >>> } > >>> > >>> static inline void platform_do_lowpower(unsigned int cpu, int *spurious) > >>> @@ -95,8 +103,22 @@ static inline void platform_do_lowpower(unsigned int cpu, int *spurious) > >>> for (;;) { > >>> > >>> /* make cpu1 to be turned off at next WFI command */ > >>> - if (cpu == 1) > >>> + if (cpu == 1) { > >> > >> I think this patch should be rebased on top of my "[PATCH] ARM: EXYNOS: > >> Fix core ID used by platsmp and hotplug code". Then instead of if (cpu > >> == 1) you would just use EXYNOS_ARM_CORE_OPTION(core_id). > >> > >> Also same comment as above, I believe this is also needed on Exynos4412. > > > > Probably your patch needs rebasing too. I couldn't apply (cleanly) on > > current Linus' tree and on Kukjin's for-next. What are the requirements > > for it? > > Hmm, I based it on Kukjin's for-next from the day I sent the patch, > 23.05 if I remember correctly. AFAICT everything needed by this patch is > already merged in Kukjin's tree (and I believe already was when I sent > that patch). > > To make sure, I'm talking about this patch: > http://www.spinics.net/lists/linux-samsung-soc/msg31604.html Yep, that's the patch but still it does not apply cleanly :). Anyway I'll send next version of my patch reflecting your comments: 1. Limit to all Exynos4 SoCs. 2. Rebase on your patch to utilize EXYNOS_ARM_CORE_OPTION(core_id). Best regards, Krzysztof