On czw, 2014-05-15 at 13:18 +0200, Krzysztof Kozlowski wrote:
> Without software reset the secondary CPU does not power up and
> exynos_boot_secondary() ends with pen_release equal to 1. This can be
> observed in dmesg:
> CPU1: failed to come online
> Brought up 1 CPUs
> SMP: Total of 1 processors activated.
> CPU: All CPU(s) started in SVC mode.
>
> When booting the secondary CPU on Exynos3250 execute also software
> reset for core 1.
>
> Signed-off-by: Krzysztof Kozlowski <k.kozlow...@samsung.com>
I am humbly reminding myself - any comments on this patch?
Best regards,
Krzysztof
> ---
> arch/arm/mach-exynos/platsmp.c | 22 ++++++++++++++++++++++
> arch/arm/mach-exynos/regs-pmu.h | 3 +++
> 2 files changed, 25 insertions(+)
>
> diff --git a/arch/arm/mach-exynos/platsmp.c b/arch/arm/mach-exynos/platsmp.c
> index 8b88eb2f077b..64ec5ca18f60 100644
> --- a/arch/arm/mach-exynos/platsmp.c
> +++ b/arch/arm/mach-exynos/platsmp.c
> @@ -76,6 +76,25 @@ static inline void __iomem *cpu_boot_reg(int cpu)
> }
>
> /*
> + * Set wake up by local power mode and execute software reset for given core.
> + *
> + * Currently this is needed only when booting secondary CPU on Exynos3250.
> + */
> +static inline void exynos_core_restart(u32 core_id)
> +{
> + if (of_machine_is_compatible("samsung,exynos3250")) {
> + u32 val;
> +
> + val = __raw_readl(S5P_ARM_CORE_STATUS(core_id));
> + val |= S5P_CORE_WAKEUP_FROM_LOCAL_CFG;
> + __raw_writel(val, S5P_ARM_CORE_STATUS(core_id));
> +
> + pr_info("CPU%u: Software reset\n", core_id);
> + __raw_writel(EXYNOS_CORE_PO_RESET(core_id), EXYNOS_SWRESET);
> + }
> +}
> +
> +/*
> * Write pen_release in a way that is guaranteed to be visible to all
> * observers, irrespective of whether they're taking part in coherency
> * or not. This is necessary for the hotplug code to work reliably.
> @@ -155,6 +174,9 @@ static int exynos_boot_secondary(unsigned int cpu, struct
> task_struct *idle)
> return -ETIMEDOUT;
> }
> }
> +
> + exynos_core_restart(core_id);
> +
> /*
> * Send the secondary CPU a soft interrupt, thereby causing
> * the boot monitor to read the system wide flags register,
> diff --git a/arch/arm/mach-exynos/regs-pmu.h b/arch/arm/mach-exynos/regs-pmu.h
> index d94bbc85d7e0..3ecbb4fe227b 100644
> --- a/arch/arm/mach-exynos/regs-pmu.h
> +++ b/arch/arm/mach-exynos/regs-pmu.h
> @@ -26,6 +26,8 @@
> #define S5P_USE_STANDBY_WFI0 (1 << 16)
> #define S5P_USE_STANDBY_WFE0 (1 << 24)
>
> +#define EXYNOS_CORE_PO_RESET(n) ((1 << 4) << n)
> +
> #define EXYNOS_SWRESET S5P_PMUREG(0x0400)
> #define EXYNOS5440_SWRESET S5P_PMUREG(0x00C4)
>
> @@ -117,6 +119,7 @@
> #define S5P_PAD_RET_EBIB_OPTION S5P_PMUREG(0x31A8)
>
> #define S5P_CORE_LOCAL_PWR_EN 0x3
> +#define S5P_CORE_WAKEUP_FROM_LOCAL_CFG (0x3 << 8)
> #define S5P_INT_LOCAL_PWR_EN 0x7
>
> #define S5P_CHECK_SLEEP 0x00000BAD
--
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