From 254056f3b12563c11e6dbcfad2fbfce20a4f3302 Mon Sep 17 00:00:00 2001 From: Colin Cross Date: Thu, 10 Feb 2011 12:54:10 -0800 Subject: ARM: gic: Use cpu pm notifiers to save gic state When the cpu is powered down in a low power mode, the gic cpu interface may be reset, and when the cpu cluster is powered down, the gic distributor may also be reset. This patch uses CPU_PM_ENTER and CPU_PM_EXIT notifiers to save and restore the gic cpu interface registers, and the CPU_CLUSTER_PM_ENTER and CPU_CLUSTER_PM_EXIT notifiers to save and restore the gic distributor registers. Original-author: Gary King Signed-off-by: Colin Cross Signed-off-by: Santosh Shilimkar Tested-and-Acked-by: Shawn Guo Tested-by: Vishwanath BS --- arch/arm/common/gic.c | 187 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 187 insertions(+) (limited to 'arch/arm/common') diff --git a/arch/arm/common/gic.c b/arch/arm/common/gic.c index 3227ca952a1..66c7c482010 100644 --- a/arch/arm/common/gic.c +++ b/arch/arm/common/gic.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include @@ -276,6 +277,8 @@ static void __init gic_dist_init(struct gic_chip_data *gic, if (gic_irqs > 1020) gic_irqs = 1020; + gic->gic_irqs = gic_irqs; + /* * Set all global interrupts to be level triggered, active low. */ @@ -343,6 +346,189 @@ static void __cpuinit gic_cpu_init(struct gic_chip_data *gic) writel_relaxed(1, base + GIC_CPU_CTRL); } +#ifdef CONFIG_CPU_PM +/* + * Saves the GIC distributor registers during suspend or idle. Must be called + * with interrupts disabled but before powering down the GIC. After calling + * this function, no interrupts will be delivered by the GIC, and another + * platform-specific wakeup source must be enabled. + */ +static void gic_dist_save(unsigned int gic_nr) +{ + unsigned int gic_irqs; + void __iomem *dist_base; + int i; + + if (gic_nr >= MAX_GIC_NR) + BUG(); + + gic_irqs = gic_data[gic_nr].gic_irqs; + dist_base = gic_data[gic_nr].dist_base; + + if (!dist_base) + return; + + for (i = 0; i < DIV_ROUND_UP(gic_irqs, 16); i++) + gic_data[gic_nr].saved_spi_conf[i] = + readl_relaxed(dist_base + GIC_DIST_CONFIG + i * 4); + + for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++) + gic_data[gic_nr].saved_spi_target[i] = + readl_relaxed(dist_base + GIC_DIST_TARGET + i * 4); + + for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++) + gic_data[gic_nr].saved_spi_enable[i] = + readl_relaxed(dist_base + GIC_DIST_ENABLE_SET + i * 4); +} + +/* + * Restores the GIC distributor registers during resume or when coming out of + * idle. Must be called before enabling interrupts. If a level interrupt + * that occured while the GIC was suspended is still present, it will be + * handled normally, but any edge interrupts that occured will not be seen by + * the GIC and need to be handled by the platform-specific wakeup source. + */ +static void gic_dist_restore(unsigned int gic_nr) +{ + unsigned int gic_irqs; + unsigned int i; + void __iomem *dist_base; + + if (gic_nr >= MAX_GIC_NR) + BUG(); + + gic_irqs = gic_data[gic_nr].gic_irqs; + dist_base = gic_data[gic_nr].dist_base; + + if (!dist_base) + return; + + writel_relaxed(0, dist_base + GIC_DIST_CTRL); + + for (i = 0; i < DIV_ROUND_UP(gic_irqs, 16); i++) + writel_relaxed(gic_data[gic_nr].saved_spi_conf[i], + dist_base + GIC_DIST_CONFIG + i * 4); + + for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++) + writel_relaxed(0xa0a0a0a0, + dist_base + GIC_DIST_PRI + i * 4); + + for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++) + writel_relaxed(gic_data[gic_nr].saved_spi_target[i], + dist_base + GIC_DIST_TARGET + i * 4); + + for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++) + writel_relaxed(gic_data[gic_nr].saved_spi_enable[i], + dist_base + GIC_DIST_ENABLE_SET + i * 4); + + writel_relaxed(1, dist_base + GIC_DIST_CTRL); +} + +static void gic_cpu_save(unsigned int gic_nr) +{ + int i; + u32 *ptr; + void __iomem *dist_base; + void __iomem *cpu_base; + + if (gic_nr >= MAX_GIC_NR) + BUG(); + + dist_base = gic_data[gic_nr].dist_base; + cpu_base = gic_data[gic_nr].cpu_base; + + if (!dist_base || !cpu_base) + return; + + ptr = __this_cpu_ptr(gic_data[gic_nr].saved_ppi_enable); + for (i = 0; i < DIV_ROUND_UP(32, 32); i++) + ptr[i] = readl_relaxed(dist_base + GIC_DIST_ENABLE_SET + i * 4); + + ptr = __this_cpu_ptr(gic_data[gic_nr].saved_ppi_conf); + for (i = 0; i < DIV_ROUND_UP(32, 16); i++) + ptr[i] = readl_relaxed(dist_base + GIC_DIST_CONFIG + i * 4); + +} + +static void gic_cpu_restore(unsigned int gic_nr) +{ + int i; + u32 *ptr; + void __iomem *dist_base; + void __iomem *cpu_base; + + if (gic_nr >= MAX_GIC_NR) + BUG(); + + dist_base = gic_data[gic_nr].dist_base; + cpu_base = gic_data[gic_nr].cpu_base; + + if (!dist_base || !cpu_base) + return; + + ptr = __this_cpu_ptr(gic_data[gic_nr].saved_ppi_enable); + for (i = 0; i < DIV_ROUND_UP(32, 32); i++) + writel_relaxed(ptr[i], dist_base + GIC_DIST_ENABLE_SET + i * 4); + + ptr = __this_cpu_ptr(gic_data[gic_nr].saved_ppi_conf); + for (i = 0; i < DIV_ROUND_UP(32, 16); i++) + writel_relaxed(ptr[i], dist_base + GIC_DIST_CONFIG + i * 4); + + for (i = 0; i < DIV_ROUND_UP(32, 4); i++) + writel_relaxed(0xa0a0a0a0, dist_base + GIC_DIST_PRI + i * 4); + + writel_relaxed(0xf0, cpu_base + GIC_CPU_PRIMASK); + writel_relaxed(1, cpu_base + GIC_CPU_CTRL); +} + +static int gic_notifier(struct notifier_block *self, unsigned long cmd, void *v) +{ + int i; + + for (i = 0; i < MAX_GIC_NR; i++) { + switch (cmd) { + case CPU_PM_ENTER: + gic_cpu_save(i); + break; + case CPU_PM_ENTER_FAILED: + case CPU_PM_EXIT: + gic_cpu_restore(i); + break; + case CPU_CLUSTER_PM_ENTER: + gic_dist_save(i); + break; + case CPU_CLUSTER_PM_ENTER_FAILED: + case CPU_CLUSTER_PM_EXIT: + gic_dist_restore(i); + break; + } + } + + return NOTIFY_OK; +} + +static struct notifier_block gic_notifier_block = { + .notifier_call = gic_notifier, +}; + +static void __init gic_pm_init(struct gic_chip_data *gic) +{ + gic->saved_ppi_enable = __alloc_percpu(DIV_ROUND_UP(32, 32) * 4, + sizeof(u32)); + BUG_ON(!gic->saved_ppi_enable); + + gic->saved_ppi_conf = __alloc_percpu(DIV_ROUND_UP(32, 16) * 4, + sizeof(u32)); + BUG_ON(!gic->saved_ppi_conf); + + cpu_pm_register_notifier(&gic_notifier_block); +} +#else +static void __init gic_pm_init(struct gic_chip_data *gic) +{ +} +#endif + void __init gic_init(unsigned int gic_nr, unsigned int irq_start, void __iomem *dist_base, void __iomem *cpu_base) { @@ -360,6 +546,7 @@ void __init gic_init(unsigned int gic_nr, unsigned int irq_start, gic_dist_init(gic, irq_start); gic_cpu_init(gic); + gic_pm_init(gic); } void __cpuinit gic_secondary_init(unsigned int gic_nr) -- cgit v1.2.3-70-g09d2