[PATCH] ARM: EXYNOS: Fix incorrect usage of S5P_ARM_CORE1_* registers

Kukjin Kim kgene.kim at samsung.com
Tue Jun 18 13:59:58 EDT 2013


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 at vger.kernel.org
>> Signed-off-by: Tomasz Figa<t.figa at samsung.com>
>> Signed-off-by: Kyungmin Park<kyungmin.park at samsung.com>
>> ---
>>   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);
>> +		__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))
>>   			&  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;
>>   		}
> --



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