From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756760Ab3FSNYQ (ORCPT ); Wed, 19 Jun 2013 09:24:16 -0400 Received: from mail-ob0-f182.google.com ([209.85.214.182]:46311 "EHLO mail-ob0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756640Ab3FSNYM (ORCPT ); Wed, 19 Jun 2013 09:24:12 -0400 MIME-Version: 1.0 In-Reply-To: <8974257.1Thh8U4Een@amdc1227> References: <1371569191-2364-1-git-send-email-t.figa@samsung.com> <51C0A01E.5020206@samsung.com> <8974257.1Thh8U4Een@amdc1227> Date: Wed, 19 Jun 2013 18:54:12 +0530 Message-ID: Subject: Re: [PATCH] ARM: EXYNOS: Fix incorrect usage of S5P_ARM_CORE1_* registers From: Chander Kashyap To: Tomasz Figa Cc: Kukjin Kim , Tomasz Figa , "linux-samsung-soc@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , Russell King - ARM Linux , Jingoo Han , Jonghwan Choi , Abhilash Kesavan , linux-kernel@vger.kernel.org, stable@vger.kernel.org, Kyungmin Park , Arnd Bergmann , Olof Johansson , Nicolas Pitre , Will Deacon , Lorenzo Pieralisi , Stephen Boyd Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 19 June 2013 18:20, Tomasz Figa wrote: > On Wednesday 19 of June 2013 17:39:21 Chander Kashyap wrote: >> On 18 June 2013 23:29, Kukjin Kim wrote: >> > On 06/19/13 02:45, Tomasz Figa wrote: >> >> Ccing Arnd and Olof, because I forgot to add them to git send-email... >> >> >> >> Sorry for the noise. >> >> >> >> On Tuesday 18 of June 2013 17:26:31 Tomasz Figa wrote: >> >>> S5P_ARM_CORE1_* registers affect only core 1. To control further >> >>> cores >> >>> properly another registers must be used. >> >>> >> >>> This patch replaces S5P_ARM_CORE1_* register definitions with >> >>> S5P_ARM_CORE_*(x) macro which return addresses of registers for >> >>> specified core. >> >>> >> >>> This fixes CPU hotplug on quad core Exynos SoCs on which currently >> >>> offlining CPUs 2 or 3 caused CPU 1 to be turned off. >> >> >> >> Obviously this doesn't happen currently because of the if (cpu == 1), >> >> but> >> > Yes, not happened...and just note exynos5440 doesn't support hotplug :) >> > so this is available on exynos4412 and added 5420. >> > >> >> if logical cpu1 turned out not to be physical cpu1, then it would >> >> crash. >> >> >> >> Best regards, >> >> Tomasz >> >> >> >>> In addition, >> >>> bring-up of CPU 2 and 3 is fixed on boards where bootloader powers >> >>> off >> >>> secondary cores by default. >> > >> > I need to test on board about above... >> > >> >>> Cc: stable@vger.kernel.org >> >>> Signed-off-by: Tomasz Figa >> >>> Signed-off-by: Kyungmin Park >> >>> --- >> >>> >> >>> arch/arm/mach-exynos/hotplug.c | 9 +++++---- >> >>> arch/arm/mach-exynos/include/mach/regs-pmu.h | 10 +++++++--- >> >>> arch/arm/mach-exynos/platsmp.c | 9 +++++---- >> >>> 3 files changed, 17 insertions(+), 11 deletions(-) >> >>> >> >>> diff --git a/arch/arm/mach-exynos/hotplug.c >> >>> b/arch/arm/mach-exynos/hotplug.c index af90cfa..c089943 100644 >> >>> --- a/arch/arm/mach-exynos/hotplug.c >> >>> +++ b/arch/arm/mach-exynos/hotplug.c >> >>> @@ -93,10 +93,11 @@ static inline void cpu_leave_lowpower(void) >> >>> >> >>> static inline void platform_do_lowpower(unsigned int cpu, int >> >>> >> >>> *spurious) { >> >>> >> >>> for (;;) { >> >>> >> >>> + void __iomem *reg_base; >> >>> + unsigned int phys_cpu = cpu_logical_map(cpu); >> >>> >> >>> - /* make cpu1 to be turned off at next WFI command */ >> >>> - if (cpu == 1) >> >>> - __raw_writel(0, S5P_ARM_CORE1_CONFIGURATION); >> >>> + reg_base = S5P_ARM_CORE_CONFIGURATION(phys_cpu); >> >> Tomasz, >> This will break for non-zero, MPIDR value. Say if MPIDR is 1 then for >> cpu0 phys_cpu value will be 0x100, >> and address calculation will be (S5P_ARM_CORE0_CONFIGURATION + >> ((0x101) * 0x80)), which is wrong. > > Hmm, according to the code initializing __cpu_logical_map[] array this is > not true. > > Here's the code: > > https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/tree/arch/arm/kernel/setup.c?id=refs/tags/next-20130619#n468 > > and for used macros and bitmasks: > > https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/tree/arch/arm/include/asm/cputype.h?id=refs/tags/next-20130619#n45 > > Now the structure of the MPIDR register: > > http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0388e/CIHEBGFG.html > > As you can see, the value read from the register in > smp_setup_processor_id() is only the physical CPU ID, so I don't see any > problem here. Kindly look at implementation of "arm_dt_init_cpu_maps" in "arch/arm/kernel/devtree.c". When you pass the cpu nodes thru DT, and cluster id is non zero, the phys_cpu will include clusterID. Say e.g exynos4210 has CLusterID=9, hence phys_cpu value for cpu0 will be 0x901. > > If I'm wrong, feel free to correct me. > > Cc'ing people who should have more knowledge on this. > > Best regards, > Tomasz > >> >>> + __raw_writel(0, reg_base); >> >>> >> >>> /* >> >>> >> >>> * here's the WFI >> >>> >> >>> @@ -106,7 +107,7 @@ static inline void platform_do_lowpower(unsigned >> >>> int >> >>> cpu, int *spurious) >> >>> >> >>> : "memory", "cc"); >> >>> >> >>> - if (pen_release == cpu_logical_map(cpu)) { >> >>> + if (pen_release == phys_cpu) { >> >>> >> >>> /* >> >>> >> >>> * OK, proper wakeup, we're done >> >>> */ >> >>> >> >>> diff --git a/arch/arm/mach-exynos/include/mach/regs-pmu.h >> >>> b/arch/arm/mach-exynos/include/mach/regs-pmu.h index 57344b7..cf40b86 >> >>> 100644 >> >>> --- a/arch/arm/mach-exynos/include/mach/regs-pmu.h >> >>> +++ b/arch/arm/mach-exynos/include/mach/regs-pmu.h >> >>> @@ -125,10 +125,14 @@ >> >>> >> >>> #define S5P_GPS_ALIVE_LOWPWR S5P_PMUREG(0x13A0) >> >>> >> >>> #define S5P_ARM_CORE0_CONFIGURATION S5P_PMUREG(0x2000) >> >>> >> >>> +#define S5P_ARM_CORE0_STATUS S5P_PMUREG(0x2004) >> >>> >> >>> #define S5P_ARM_CORE0_OPTION S5P_PMUREG(0x2008) >> >>> >> >>> -#define S5P_ARM_CORE1_CONFIGURATION S5P_PMUREG(0x2080) >> >>> -#define S5P_ARM_CORE1_STATUS S5P_PMUREG(0x2084) >> >>> -#define S5P_ARM_CORE1_OPTION S5P_PMUREG(0x2088) >> >>> +#define S5P_ARM_CORE_CONFIGURATION(_nr) \ >> >>> + (S5P_ARM_CORE0_CONFIGURATION + ((_nr) * 0x80)) >> >>> +#define S5P_ARM_CORE_STATUS(_nr) \ >> >>> + (S5P_ARM_CORE0_STATUS + ((_nr) * 0x80)) >> >>> +#define S5P_ARM_CORE_OPTION(_nr) \ >> >>> + (S5P_ARM_CORE0_OPTION + ((_nr) * 0x80)) >> >>> >> >>> #define S5P_ARM_COMMON_OPTION S5P_PMUREG(0x2408) >> >>> #define S5P_TOP_PWR_OPTION S5P_PMUREG(0x2C48) >> >>> >> >>> diff --git a/arch/arm/mach-exynos/platsmp.c >> >>> b/arch/arm/mach-exynos/platsmp.c index d9c6d0a..2cbabc8 100644 >> >>> --- a/arch/arm/mach-exynos/platsmp.c >> >>> +++ b/arch/arm/mach-exynos/platsmp.c >> >>> @@ -109,14 +109,15 @@ static int __cpuinit >> >>> exynos_boot_secondary(unsigned int cpu, struct task_struct */ >> >>> >> >>> write_pen_release(phys_cpu); >> >>> >> >>> - if (!(__raw_readl(S5P_ARM_CORE1_STATUS)& >> >>> S5P_CORE_LOCAL_PWR_EN))>> >> >> { >> >> >> >>> + if (!(__raw_readl(S5P_ARM_CORE_STATUS(phys_cpu)) >> >>> + & S5P_CORE_LOCAL_PWR_EN)) { >> >>> >> >>> __raw_writel(S5P_CORE_LOCAL_PWR_EN, >> >>> >> >>> - S5P_ARM_CORE1_CONFIGURATION); >> >>> + S5P_ARM_CORE_CONFIGURATION(phys_cpu)); >> >>> >> >>> timeout = 10; >> >>> >> >>> /* wait max 10 ms until cpu1 is on */ >> >>> >> >>> - while ((__raw_readl(S5P_ARM_CORE1_STATUS) >> >>> + while ((__raw_readl(S5P_ARM_CORE_STATUS(phys_cpu)) >> >> Ditto >> >> >>> & S5P_CORE_LOCAL_PWR_EN) != >> >>> >> >>> S5P_CORE_LOCAL_PWR_EN) >> >> >> >> { >> >> >> >>> if (timeout-- == 0) >> >>> >> >>> break; >> >>> >> >>> @@ -125,7 +126,7 @@ static int __cpuinit >> >>> exynos_boot_secondary(unsigned >> >>> int cpu, struct task_struct } >> >>> >> >>> if (timeout == 0) { >> >>> >> >>> - printk(KERN_ERR "cpu1 power enable failed"); >> >>> + printk(KERN_ERR "cpu%u power enable failed", >> >>> cpu); >> >>> >> >>> spin_unlock(&boot_lock); >> >>> return -ETIMEDOUT; >> >>> >> >>> } >> >> >> >> -- >> > >> > -- >> > To unsubscribe from this list: send the line "unsubscribe >> > linux-samsung-soc" in >> > the body of a message to majordomo@vger.kernel.org >> > More majordomo info at http://vger.kernel.org/majordomo-info.html >> >> -- >> with warm regards, >> Chander Kashyap >> -- >> To unsubscribe from this list: send the line "unsubscribe >> linux-samsung-soc" in the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html -- with warm regards, Chander Kashyap