diff options
Diffstat (limited to 'arch/arm/mach-s5pv310/irq-combiner.c')
-rw-r--r-- | arch/arm/mach-s5pv310/irq-combiner.c | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/arch/arm/mach-s5pv310/irq-combiner.c b/arch/arm/mach-s5pv310/irq-combiner.c new file mode 100644 index 00000000000..0f7052164f2 --- /dev/null +++ b/arch/arm/mach-s5pv310/irq-combiner.c @@ -0,0 +1,125 @@ +/* linux/arch/arm/mach-s5pv310/irq-combiner.c + * + * Copyright (c) 2010 Samsung Electronics Co., Ltd. + * http://www.samsung.com + * + * Based on arch/arm/common/gic.c + * + * IRQ COMBINER support + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. +*/ + +#include <linux/io.h> + +#include <asm/mach/irq.h> + +#define COMBINER_ENABLE_SET 0x0 +#define COMBINER_ENABLE_CLEAR 0x4 +#define COMBINER_INT_STATUS 0xC + +static DEFINE_SPINLOCK(irq_controller_lock); + +struct combiner_chip_data { + unsigned int irq_offset; + void __iomem *base; +}; + +static struct combiner_chip_data combiner_data[MAX_COMBINER_NR]; + +static inline void __iomem *combiner_base(unsigned int irq) +{ + struct combiner_chip_data *combiner_data = get_irq_chip_data(irq); + return combiner_data->base; +} + +static void combiner_mask_irq(unsigned int irq) +{ + u32 mask = 1 << (irq % 32); + + __raw_writel(mask, combiner_base(irq) + COMBINER_ENABLE_CLEAR); +} + +static void combiner_unmask_irq(unsigned int irq) +{ + u32 mask = 1 << (irq % 32); + + __raw_writel(mask, combiner_base(irq) + COMBINER_ENABLE_SET); +} + +static void combiner_handle_cascade_irq(unsigned int irq, struct irq_desc *desc) +{ + struct combiner_chip_data *chip_data = get_irq_data(irq); + struct irq_chip *chip = get_irq_chip(irq); + unsigned int cascade_irq, combiner_irq; + unsigned long status; + + /* primary controller ack'ing */ + chip->ack(irq); + + spin_lock(&irq_controller_lock); + status = __raw_readl(chip_data->base + COMBINER_INT_STATUS); + spin_unlock(&irq_controller_lock); + + if (status == 0) + goto out; + + for (combiner_irq = 0; combiner_irq < 32; combiner_irq++) { + if (status & 0x1) + break; + status >>= 1; + } + + cascade_irq = combiner_irq + (chip_data->irq_offset & ~31); + if (unlikely(cascade_irq >= NR_IRQS)) + do_bad_IRQ(cascade_irq, desc); + else + generic_handle_irq(cascade_irq); + + out: + /* primary controller unmasking */ + chip->unmask(irq); +} + +static struct irq_chip combiner_chip = { + .name = "COMBINER", + .mask = combiner_mask_irq, + .unmask = combiner_unmask_irq, +}; + +void __init combiner_cascade_irq(unsigned int combiner_nr, unsigned int irq) +{ + if (combiner_nr >= MAX_COMBINER_NR) + BUG(); + if (set_irq_data(irq, &combiner_data[combiner_nr]) != 0) + BUG(); + set_irq_chained_handler(irq, combiner_handle_cascade_irq); +} + +void __init combiner_init(unsigned int combiner_nr, void __iomem *base, + unsigned int irq_start) +{ + unsigned int i; + + if (combiner_nr >= MAX_COMBINER_NR) + BUG(); + + combiner_data[combiner_nr].base = base; + combiner_data[combiner_nr].irq_offset = irq_start; + + /* Disable all interrupts */ + + __raw_writel(0xffffffff, base + COMBINER_ENABLE_CLEAR); + + /* Setup the Linux IRQ subsystem */ + + for (i = irq_start; i < combiner_data[combiner_nr].irq_offset + + MAX_IRQ_IN_COMBINER; i++) { + set_irq_chip(i, &combiner_chip); + set_irq_chip_data(i, &combiner_data[combiner_nr]); + set_irq_handler(i, handle_level_irq); + set_irq_flags(i, IRQF_VALID | IRQF_PROBE); + } +} |