diff options
Diffstat (limited to 'arch/mips/bcm3384/irq.c')
| -rw-r--r-- | arch/mips/bcm3384/irq.c | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/arch/mips/bcm3384/irq.c b/arch/mips/bcm3384/irq.c new file mode 100644 index 00000000000..0fb5134fb83 --- /dev/null +++ b/arch/mips/bcm3384/irq.c @@ -0,0 +1,193 @@ +/* + * 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. + * + * Partially based on arch/mips/ralink/irq.c + * + * Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org> + * Copyright (C) 2013 John Crispin <blogic@openwrt.org> + * Copyright (C) 2014 Kevin Cernekee <cernekee@gmail.com> + */ + +#include <linux/io.h> +#include <linux/bitops.h> +#include <linux/of_platform.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/irqdomain.h> +#include <linux/interrupt.h> +#include <linux/slab.h> +#include <linux/spinlock.h> + +#include <asm/bmips.h> +#include <asm/irq_cpu.h> +#include <asm/mipsregs.h> + +/* INTC register offsets */ +#define INTC_REG_ENABLE 0x00 +#define INTC_REG_STATUS 0x04 + +#define MAX_WORDS 2 +#define IRQS_PER_WORD 32 + +struct bcm3384_intc { + int n_words; + void __iomem *reg[MAX_WORDS]; + u32 enable[MAX_WORDS]; + spinlock_t lock; +}; + +static void bcm3384_intc_irq_unmask(struct irq_data *d) +{ + struct bcm3384_intc *priv = d->domain->host_data; + unsigned long flags; + int idx = d->hwirq / IRQS_PER_WORD; + int bit = d->hwirq % IRQS_PER_WORD; + + spin_lock_irqsave(&priv->lock, flags); + priv->enable[idx] |= BIT(bit); + __raw_writel(priv->enable[idx], priv->reg[idx] + INTC_REG_ENABLE); + spin_unlock_irqrestore(&priv->lock, flags); +} + +static void bcm3384_intc_irq_mask(struct irq_data *d) +{ + struct bcm3384_intc *priv = d->domain->host_data; + unsigned long flags; + int idx = d->hwirq / IRQS_PER_WORD; + int bit = d->hwirq % IRQS_PER_WORD; + + spin_lock_irqsave(&priv->lock, flags); + priv->enable[idx] &= ~BIT(bit); + __raw_writel(priv->enable[idx], priv->reg[idx] + INTC_REG_ENABLE); + spin_unlock_irqrestore(&priv->lock, flags); +} + +static struct irq_chip bcm3384_intc_irq_chip = { + .name = "INTC", + .irq_unmask = bcm3384_intc_irq_unmask, + .irq_mask = bcm3384_intc_irq_mask, + .irq_mask_ack = bcm3384_intc_irq_mask, +}; + +unsigned int get_c0_compare_int(void) +{ + return CP0_LEGACY_COMPARE_IRQ; +} + +static void bcm3384_intc_irq_handler(unsigned int irq, struct irq_desc *desc) +{ + struct irq_domain *domain = irq_get_handler_data(irq); + struct bcm3384_intc *priv = domain->host_data; + unsigned long flags; + unsigned int idx; + + for (idx = 0; idx < priv->n_words; idx++) { + unsigned long pending; + int hwirq; + + spin_lock_irqsave(&priv->lock, flags); + pending = __raw_readl(priv->reg[idx] + INTC_REG_STATUS) & + priv->enable[idx]; + spin_unlock_irqrestore(&priv->lock, flags); + + for_each_set_bit(hwirq, &pending, IRQS_PER_WORD) { + generic_handle_irq(irq_find_mapping(domain, + hwirq + idx * IRQS_PER_WORD)); + } + } +} + +asmlinkage void plat_irq_dispatch(void) +{ + unsigned long pending = + (read_c0_status() & read_c0_cause() & ST0_IM) >> STATUSB_IP0; + int bit; + + for_each_set_bit(bit, &pending, 8) + do_IRQ(MIPS_CPU_IRQ_BASE + bit); +} + +static int intc_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw) +{ + irq_set_chip_and_handler(irq, &bcm3384_intc_irq_chip, handle_level_irq); + return 0; +} + +static const struct irq_domain_ops irq_domain_ops = { + .xlate = irq_domain_xlate_onecell, + .map = intc_map, +}; + +static int __init ioremap_one_pair(struct bcm3384_intc *priv, + struct device_node *node, + int idx) +{ + struct resource res; + + if (of_address_to_resource(node, idx, &res)) + return 0; + + if (request_mem_region(res.start, resource_size(&res), + res.name) < 0) + pr_err("Failed to request INTC register region\n"); + + priv->reg[idx] = ioremap_nocache(res.start, resource_size(&res)); + if (!priv->reg[idx]) + panic("Failed to ioremap INTC register range"); + + /* start up with everything masked before we hook the parent IRQ */ + __raw_writel(0, priv->reg[idx] + INTC_REG_ENABLE); + priv->enable[idx] = 0; + + return IRQS_PER_WORD; +} + +static int __init intc_of_init(struct device_node *node, + struct device_node *parent) +{ + struct irq_domain *domain; + unsigned int parent_irq, n_irqs = 0; + struct bcm3384_intc *priv; + + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + panic("Failed to allocate bcm3384_intc struct"); + + spin_lock_init(&priv->lock); + + parent_irq = irq_of_parse_and_map(node, 0); + if (!parent_irq) + panic("Failed to get INTC IRQ"); + + n_irqs += ioremap_one_pair(priv, node, 0); + n_irqs += ioremap_one_pair(priv, node, 1); + + if (!n_irqs) + panic("Failed to map INTC registers"); + + priv->n_words = n_irqs / IRQS_PER_WORD; + domain = irq_domain_add_linear(node, n_irqs, &irq_domain_ops, priv); + if (!domain) + panic("Failed to add irqdomain"); + + irq_set_chained_handler(parent_irq, bcm3384_intc_irq_handler); + irq_set_handler_data(parent_irq, domain); + + return 0; +} + +static struct of_device_id of_irq_ids[] __initdata = { + { .compatible = "mti,cpu-interrupt-controller", + .data = mips_cpu_intc_init }, + { .compatible = "brcm,bcm3384-intc", + .data = intc_of_init }, + {}, +}; + +void __init arch_init_irq(void) +{ + bmips_tp1_irqs = 0; + of_irq_init(of_irq_ids); +} |