diff options
Diffstat (limited to 'drivers/irqchip/exynos-combiner.c')
| -rw-r--r-- | drivers/irqchip/exynos-combiner.c | 226 |
1 files changed, 226 insertions, 0 deletions
diff --git a/drivers/irqchip/exynos-combiner.c b/drivers/irqchip/exynos-combiner.c new file mode 100644 index 00000000000..f8636a650cf --- /dev/null +++ b/drivers/irqchip/exynos-combiner.c @@ -0,0 +1,226 @@ +/* + * Copyright (c) 2010-2011 Samsung Electronics Co., Ltd. + * http://www.samsung.com + * + * Combiner irqchip for EXYNOS + * + * 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/err.h> +#include <linux/export.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/slab.h> +#include <linux/irqdomain.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> + +#include "irqchip.h" + +#define COMBINER_ENABLE_SET 0x0 +#define COMBINER_ENABLE_CLEAR 0x4 +#define COMBINER_INT_STATUS 0xC + +#define IRQ_IN_COMBINER 8 + +static DEFINE_SPINLOCK(irq_controller_lock); + +struct combiner_chip_data { + unsigned int hwirq_offset; + unsigned int irq_mask; + void __iomem *base; + unsigned int parent_irq; +}; + +static struct irq_domain *combiner_irq_domain; + +static inline void __iomem *combiner_base(struct irq_data *data) +{ + struct combiner_chip_data *combiner_data = + irq_data_get_irq_chip_data(data); + + return combiner_data->base; +} + +static void combiner_mask_irq(struct irq_data *data) +{ + u32 mask = 1 << (data->hwirq % 32); + + __raw_writel(mask, combiner_base(data) + COMBINER_ENABLE_CLEAR); +} + +static void combiner_unmask_irq(struct irq_data *data) +{ + u32 mask = 1 << (data->hwirq % 32); + + __raw_writel(mask, combiner_base(data) + COMBINER_ENABLE_SET); +} + +static void combiner_handle_cascade_irq(unsigned int irq, struct irq_desc *desc) +{ + struct combiner_chip_data *chip_data = irq_get_handler_data(irq); + struct irq_chip *chip = irq_get_chip(irq); + unsigned int cascade_irq, combiner_irq; + unsigned long status; + + chained_irq_enter(chip, desc); + + spin_lock(&irq_controller_lock); + status = __raw_readl(chip_data->base + COMBINER_INT_STATUS); + spin_unlock(&irq_controller_lock); + status &= chip_data->irq_mask; + + if (status == 0) + goto out; + + combiner_irq = chip_data->hwirq_offset + __ffs(status); + cascade_irq = irq_find_mapping(combiner_irq_domain, combiner_irq); + + if (unlikely(!cascade_irq)) + handle_bad_irq(irq, desc); + else + generic_handle_irq(cascade_irq); + + out: + chained_irq_exit(chip, desc); +} + +#ifdef CONFIG_SMP +static int combiner_set_affinity(struct irq_data *d, + const struct cpumask *mask_val, bool force) +{ + struct combiner_chip_data *chip_data = irq_data_get_irq_chip_data(d); + struct irq_chip *chip = irq_get_chip(chip_data->parent_irq); + struct irq_data *data = irq_get_irq_data(chip_data->parent_irq); + + if (chip && chip->irq_set_affinity) + return chip->irq_set_affinity(data, mask_val, force); + else + return -EINVAL; +} +#endif + +static struct irq_chip combiner_chip = { + .name = "COMBINER", + .irq_mask = combiner_mask_irq, + .irq_unmask = combiner_unmask_irq, +#ifdef CONFIG_SMP + .irq_set_affinity = combiner_set_affinity, +#endif +}; + +static void __init combiner_cascade_irq(struct combiner_chip_data *combiner_data, + unsigned int irq) +{ + if (irq_set_handler_data(irq, combiner_data) != 0) + BUG(); + irq_set_chained_handler(irq, combiner_handle_cascade_irq); +} + +static void __init combiner_init_one(struct combiner_chip_data *combiner_data, + unsigned int combiner_nr, + void __iomem *base, unsigned int irq) +{ + combiner_data->base = base; + combiner_data->hwirq_offset = (combiner_nr & ~3) * IRQ_IN_COMBINER; + combiner_data->irq_mask = 0xff << ((combiner_nr % 4) << 3); + combiner_data->parent_irq = irq; + + /* Disable all interrupts */ + __raw_writel(combiner_data->irq_mask, base + COMBINER_ENABLE_CLEAR); +} + +static int combiner_irq_domain_xlate(struct irq_domain *d, + struct device_node *controller, + const u32 *intspec, unsigned int intsize, + unsigned long *out_hwirq, + unsigned int *out_type) +{ + if (d->of_node != controller) + return -EINVAL; + + if (intsize < 2) + return -EINVAL; + + *out_hwirq = intspec[0] * IRQ_IN_COMBINER + intspec[1]; + *out_type = 0; + + return 0; +} + +static int combiner_irq_domain_map(struct irq_domain *d, unsigned int irq, + irq_hw_number_t hw) +{ + struct combiner_chip_data *combiner_data = d->host_data; + + irq_set_chip_and_handler(irq, &combiner_chip, handle_level_irq); + irq_set_chip_data(irq, &combiner_data[hw >> 3]); + set_irq_flags(irq, IRQF_VALID | IRQF_PROBE); + + return 0; +} + +static struct irq_domain_ops combiner_irq_domain_ops = { + .xlate = combiner_irq_domain_xlate, + .map = combiner_irq_domain_map, +}; + +static void __init combiner_init(void __iomem *combiner_base, + struct device_node *np, + unsigned int max_nr) +{ + int i, irq; + unsigned int nr_irq; + struct combiner_chip_data *combiner_data; + + nr_irq = max_nr * IRQ_IN_COMBINER; + + combiner_data = kcalloc(max_nr, sizeof (*combiner_data), GFP_KERNEL); + if (!combiner_data) { + pr_warning("%s: could not allocate combiner data\n", __func__); + return; + } + + combiner_irq_domain = irq_domain_add_linear(np, nr_irq, + &combiner_irq_domain_ops, combiner_data); + if (WARN_ON(!combiner_irq_domain)) { + pr_warning("%s: irq domain init failed\n", __func__); + return; + } + + for (i = 0; i < max_nr; i++) { + irq = irq_of_parse_and_map(np, i); + + combiner_init_one(&combiner_data[i], i, + combiner_base + (i >> 2) * 0x10, irq); + combiner_cascade_irq(&combiner_data[i], irq); + } +} + +static int __init combiner_of_init(struct device_node *np, + struct device_node *parent) +{ + void __iomem *combiner_base; + unsigned int max_nr = 20; + + combiner_base = of_iomap(np, 0); + if (!combiner_base) { + pr_err("%s: failed to map combiner registers\n", __func__); + return -ENXIO; + } + + if (of_property_read_u32(np, "samsung,combiner-nr", &max_nr)) { + pr_info("%s: number of combiners not specified, " + "setting default as %d.\n", + __func__, max_nr); + } + + combiner_init(combiner_base, np, max_nr); + + return 0; +} +IRQCHIP_DECLARE(exynos4210_combiner, "samsung,exynos4210-combiner", + combiner_of_init); |