From b3a1bde4db9889feb116330bff21214811c940e4 Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Wed, 14 Feb 2007 19:14:56 +0100 Subject: [ARM] 4108/2: Allow multiple GIC interrupt controllers in a system The current implementation only assumes one GIC to be present in the system. However, there are platforms with more than one cascaded interrupt controllers (RealView/EB MPCore for example). Signed-off-by: Catalin Marinas Signed-off-by: Russell King --- arch/arm/common/gic.c | 109 +++++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 95 insertions(+), 14 deletions(-) (limited to 'arch/arm/common') diff --git a/arch/arm/common/gic.c b/arch/arm/common/gic.c index 09b9d1b6844c..4deece5fbdf4 100644 --- a/arch/arm/common/gic.c +++ b/arch/arm/common/gic.c @@ -14,7 +14,9 @@ * * o There is one CPU Interface per CPU, which sends interrupts sent * by the Distributor, and interrupts generated locally, to the - * associated CPU. + * associated CPU. The base address of the CPU interface is usually + * aliased so that the same address points to different chips depending + * on the CPU it is accessed from. * * Note that IRQs 0-31 are special - they are local to each CPU. * As such, the enable set/clear, pending set/clear and active bit @@ -31,10 +33,38 @@ #include #include -static void __iomem *gic_dist_base; -static void __iomem *gic_cpu_base; static DEFINE_SPINLOCK(irq_controller_lock); +struct gic_chip_data { + unsigned int irq_offset; + void __iomem *dist_base; + void __iomem *cpu_base; +}; + +#ifndef MAX_GIC_NR +#define MAX_GIC_NR 1 +#endif + +static struct gic_chip_data gic_data[MAX_GIC_NR]; + +static inline void __iomem *gic_dist_base(unsigned int irq) +{ + struct gic_chip_data *gic_data = get_irq_chip_data(irq); + return gic_data->dist_base; +} + +static inline void __iomem *gic_cpu_base(unsigned int irq) +{ + struct gic_chip_data *gic_data = get_irq_chip_data(irq); + return gic_data->cpu_base; +} + +static inline unsigned int gic_irq(unsigned int irq) +{ + struct gic_chip_data *gic_data = get_irq_chip_data(irq); + return irq - gic_data->irq_offset; +} + /* * Routines to acknowledge, disable and enable interrupts * @@ -55,8 +85,8 @@ static void gic_ack_irq(unsigned int irq) u32 mask = 1 << (irq % 32); spin_lock(&irq_controller_lock); - writel(mask, gic_dist_base + GIC_DIST_ENABLE_CLEAR + (irq / 32) * 4); - writel(irq, gic_cpu_base + GIC_CPU_EOI); + writel(mask, gic_dist_base(irq) + GIC_DIST_ENABLE_CLEAR + (gic_irq(irq) / 32) * 4); + writel(gic_irq(irq), gic_cpu_base(irq) + GIC_CPU_EOI); spin_unlock(&irq_controller_lock); } @@ -65,7 +95,7 @@ static void gic_mask_irq(unsigned int irq) u32 mask = 1 << (irq % 32); spin_lock(&irq_controller_lock); - writel(mask, gic_dist_base + GIC_DIST_ENABLE_CLEAR + (irq / 32) * 4); + writel(mask, gic_dist_base(irq) + GIC_DIST_ENABLE_CLEAR + (gic_irq(irq) / 32) * 4); spin_unlock(&irq_controller_lock); } @@ -74,14 +104,14 @@ static void gic_unmask_irq(unsigned int irq) u32 mask = 1 << (irq % 32); spin_lock(&irq_controller_lock); - writel(mask, gic_dist_base + GIC_DIST_ENABLE_SET + (irq / 32) * 4); + writel(mask, gic_dist_base(irq) + GIC_DIST_ENABLE_SET + (gic_irq(irq) / 32) * 4); spin_unlock(&irq_controller_lock); } #ifdef CONFIG_SMP static void gic_set_cpu(unsigned int irq, cpumask_t mask_val) { - void __iomem *reg = gic_dist_base + GIC_DIST_TARGET + (irq & ~3); + void __iomem *reg = gic_dist_base(irq) + GIC_DIST_TARGET + (gic_irq(irq) & ~3); unsigned int shift = (irq % 4) * 8; unsigned int cpu = first_cpu(mask_val); u32 val; @@ -95,6 +125,37 @@ static void gic_set_cpu(unsigned int irq, cpumask_t mask_val) } #endif +static void fastcall gic_handle_cascade_irq(unsigned int irq, + struct irq_desc *desc) +{ + struct gic_chip_data *chip_data = get_irq_data(irq); + struct irq_chip *chip = get_irq_chip(irq); + unsigned int cascade_irq; + unsigned long status; + + /* primary controller ack'ing */ + chip->ack(irq); + + spin_lock(&irq_controller_lock); + status = readl(chip_data->cpu_base + GIC_CPU_INTACK); + spin_unlock(&irq_controller_lock); + + cascade_irq = (status & 0x3ff); + if (cascade_irq > 1020) + goto out; + if (cascade_irq < 32 || cascade_irq >= NR_IRQS) { + do_bad_IRQ(cascade_irq, desc); + goto out; + } + + cascade_irq += chip_data->irq_offset; + generic_handle_irq(cascade_irq); + + out: + /* primary controller unmasking */ + chip->unmask(irq); +} + static struct irq_chip gic_chip = { .name = "GIC", .ack = gic_ack_irq, @@ -105,15 +166,29 @@ static struct irq_chip gic_chip = { #endif }; -void __init gic_dist_init(void __iomem *base) +void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq) +{ + if (gic_nr >= MAX_GIC_NR) + BUG(); + if (set_irq_data(irq, &gic_data[gic_nr]) != 0) + BUG(); + set_irq_chained_handler(irq, gic_handle_cascade_irq); +} + +void __init gic_dist_init(unsigned int gic_nr, void __iomem *base, + unsigned int irq_start) { unsigned int max_irq, i; u32 cpumask = 1 << smp_processor_id(); + if (gic_nr >= MAX_GIC_NR) + BUG(); + cpumask |= cpumask << 8; cpumask |= cpumask << 16; - gic_dist_base = base; + gic_data[gic_nr].dist_base = base; + gic_data[gic_nr].irq_offset = (irq_start - 1) & ~31; writel(0, base + GIC_DIST_CTRL); @@ -158,8 +233,9 @@ void __init gic_dist_init(void __iomem *base) /* * Setup the Linux IRQ subsystem. */ - for (i = 29; i < max_irq; i++) { + for (i = irq_start; i < gic_data[gic_nr].irq_offset + max_irq; i++) { set_irq_chip(i, &gic_chip); + set_irq_chip_data(i, &gic_data[gic_nr]); set_irq_handler(i, handle_level_irq); set_irq_flags(i, IRQF_VALID | IRQF_PROBE); } @@ -167,9 +243,13 @@ void __init gic_dist_init(void __iomem *base) writel(1, base + GIC_DIST_CTRL); } -void __cpuinit gic_cpu_init(void __iomem *base) +void __cpuinit gic_cpu_init(unsigned int gic_nr, void __iomem *base) { - gic_cpu_base = base; + if (gic_nr >= MAX_GIC_NR) + BUG(); + + gic_data[gic_nr].cpu_base = base; + writel(0xf0, base + GIC_CPU_PRIMASK); writel(1, base + GIC_CPU_CTRL); } @@ -179,6 +259,7 @@ void gic_raise_softirq(cpumask_t cpumask, unsigned int irq) { unsigned long map = *cpus_addr(cpumask); - writel(map << 16 | irq, gic_dist_base + GIC_DIST_SOFTINT); + /* this always happens on GIC0 */ + writel(map << 16 | irq, gic_data[0].dist_base + GIC_DIST_SOFTINT); } #endif -- cgit v1.2.1