This patch adds support for CPU hotlpug for the 3 secondary cores of the exynos5440 SOC. The command to hotplug out/in is, echo 0 > /sys/devices/system/cpu/cpu[1-3]/online echo 1 > /sys/devices/system/cpu/cpu[1-3]/online
Cc: Kukjin Kim <[email protected]> Signed-off-by: Amit Daniel Kachhap <[email protected]> --- arch/arm/mach-exynos/hotplug.c | 14 +++++++++++--- arch/arm/mach-exynos/platsmp.c | 26 +++++++++++++++++++++++++- 2 files changed, 36 insertions(+), 4 deletions(-) diff --git a/arch/arm/mach-exynos/hotplug.c b/arch/arm/mach-exynos/hotplug.c index c3f825b..fbee967 100644 --- a/arch/arm/mach-exynos/hotplug.c +++ b/arch/arm/mach-exynos/hotplug.c @@ -93,11 +93,19 @@ static inline void cpu_leave_lowpower(void) static inline void platform_do_lowpower(unsigned int cpu, int *spurious) { + unsigned int val; for (;;) { - /* make cpu1 to be turned off at next WFI command */ - if (cpu == 1) - __raw_writel(0, S5P_ARM_CORE1_CONFIGURATION); + /* make cpu to be turned off at next WFI command */ + if (soc_is_exynos5440()) { + void __iomem *pmu_ctrl2_reg = S5P_VA_CHIPID + 0xc4; + val = __raw_readl(pmu_ctrl2_reg); + val |= (1 << (cpu + 8)); + __raw_writel(val, pmu_ctrl2_reg); + } else { + if (cpu == 1) + __raw_writel(0, S5P_ARM_CORE1_CONFIGURATION); + } /* * here's the WFI diff --git a/arch/arm/mach-exynos/platsmp.c b/arch/arm/mach-exynos/platsmp.c index 087b73f..8a5eb80 100644 --- a/arch/arm/mach-exynos/platsmp.c +++ b/arch/arm/mach-exynos/platsmp.c @@ -101,6 +101,7 @@ static int __cpuinit exynos_boot_secondary(unsigned int cpu, struct task_struct { unsigned long timeout; unsigned long phys_cpu = cpu_logical_map(cpu); + unsigned int val; /* * Set synchronisation state between this boot processor @@ -119,7 +120,30 @@ static int __cpuinit exynos_boot_secondary(unsigned int cpu, struct task_struct write_pen_release(phys_cpu); timeout = 10; - if (!soc_is_exynos5440()) { + if (soc_is_exynos5440()) { + void __iomem *pmu_status_reg = S5P_VA_CHIPID + 0xbc; + void __iomem *pmu_ctrl_reg = S5P_VA_CHIPID + 0xc0; + void __iomem *pmu_ctrl2_reg = S5P_VA_CHIPID + 0xc4; + + if (!(__raw_readl(pmu_status_reg) & (1 << cpu))) { + val = __raw_readl(pmu_ctrl_reg); + val |= (1 << cpu); + __raw_writel(val, pmu_ctrl_reg); + /* wait max 10 ms until cpu1 is on */ + while (!(__raw_readl(pmu_status_reg) & (1 << cpu))) { + if (timeout-- == 0) + break; + + mdelay(1); + } + } + /* clear the ctrl2 powerdown */ + val = __raw_readl(pmu_ctrl2_reg); + if (val & (1 << (cpu + 8))) { + val &= ~(1 << (cpu + 8)); + __raw_writel(val, pmu_ctrl2_reg); + } + } else { if (!(__raw_readl(S5P_ARM_CORE1_STATUS) & S5P_CORE_LOCAL_PWR_EN)) { -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
