Re: [PATCH 4/4] mcpm: exynos: populate suspend and powered_up callbacks

From: Chander Kashyap
Date: Wed Apr 23 2014 - 04:22:54 EST


On 22 April 2014 16:21, Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> wrote:
> On 04/21/2014 01:49 PM, Chander Kashyap wrote:
>>
>> In order to support cpuidle through mcpm, suspend and powered-up
>> callbacks are required in mcpm platform code.
>> Hence populate the same callbacks.
>>
>> Signed-off-by: Chander Kashyap <chander.kashyap@xxxxxxxxxx>
>> Signed-off-by: Chander Kashyap <k.chander@xxxxxxxxxxx>
>> ---
>> arch/arm/mach-exynos/mcpm-exynos.c | 53
>> ++++++++++++++++++++++++++++++++++++
>> 1 file changed, 53 insertions(+)
>>
>> diff --git a/arch/arm/mach-exynos/mcpm-exynos.c
>> b/arch/arm/mach-exynos/mcpm-exynos.c
>> index 46d4968..16af0bd 100644
>> --- a/arch/arm/mach-exynos/mcpm-exynos.c
>> +++ b/arch/arm/mach-exynos/mcpm-exynos.c
>> @@ -318,10 +318,63 @@ static int exynos_power_down_finish(unsigned int
>> cpu, unsigned int cluster)
>> return 0; /* success: the CPU is halted */
>> }
>>
>> +static void enable_coherency(void)
>> +{
>> + unsigned long v, u;
>> +
>> + asm volatile(
>> + "mrc p15, 0, %0, c1, c0, 1\n"
>> + "orr %0, %0, %2\n"
>> + "ldr %1, [%3]\n"
>> + "and %1, %1, #0\n"
>> + "orr %0, %0, %1\n"
>> + "mcr p15, 0, %0, c1, c0, 1\n"
>> + : "=&r" (v), "=&r" (u)
>> + : "Ir" (0x40), "Ir" (S5P_INFORM0)
>> + : "cc");
>> +}
>
>
> Shouldn't this function to be used from hotplug.c also ?

Hotplug.c already taking care for this. And anyhow that will go away
for mcpm dependent SoCs

>
>
>> +
>> +void exynos_powered_up(void)
>> +{
>> + unsigned int mpidr, cpu, cluster;
>> +
>> + mpidr = read_cpuid_mpidr();
>> + cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
>> + cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
>> +
>> + arch_spin_lock(&bl_lock);
>> + if (cpu_use_count[cpu][cluster] == 0)
>> + cpu_use_count[cpu][cluster] = 1;
>> + arch_spin_unlock(&bl_lock);
>> +}
>> +
>> +static void exynos_suspend(u64 residency)
>> +{
>> + unsigned int mpidr, cpunr;
>> +
>> + mpidr = read_cpuid_mpidr();
>> + cpunr = enynos_pmu_cpunr(mpidr);
>
>
> *enynos*_pmu_cpunr ?

oops, I will fix typo

>
>
>> +
>> + __raw_writel(virt_to_phys(mcpm_entry_point), REG_ENTRY_ADDR);
>> +
>> + exynos_power_down();
>> +
>> + /*
>> + * Execution reaches here only if cpu did not power down.
>> + * Hence roll back the changes done in exynos_power_down function.
>> + */
>> + __raw_writel(EXYNOS_CORE_LOCAL_PWR_EN,
>> + EXYNOS_ARM_CORE_CONFIGURATION(cpunr));
>
>
> Why don't you use the functions defined in the
>
> patch 5/5 arm: exynos: Add MCPM call-back functions

In exynos_core_power_control it powerup the alreay powered down core.
But here i need to simply set this value as core never powered down.

>
> exynos_core_power_control() ?
>
>
>> + set_cr(get_cr() | CR_C);
>> + enable_coherency();
>> +}
>> +
>> static const struct mcpm_platform_ops exynos_power_ops = {
>> .power_up = exynos_power_up,
>> .power_down = exynos_power_down,
>> .power_down_finish = exynos_power_down_finish,
>> + .suspend = exynos_suspend,
>> + .powered_up = exynos_powered_up,
>> };
>>
>> static void __init exynos_mcpm_usage_count_init(void)
>>
>
>
> --
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>
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>



--
with warm regards,
Chander Kashyap
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