/* * linux/drivers/irqchip/irq-zevio.c * * Copyright (C) 2013 Daniel Tang <tangrs@tangrs.id.au> * * 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 <linux/irq.h> #include <linux/irqchip.h> #include <linux/of.h> #include <linux/of_address.h> #include <linux/of_irq.h> #include <asm/mach/irq.h> #include <asm/exception.h> #define IO_STATUS 0x000 #define IO_RAW_STATUS 0x004 #define IO_ENABLE 0x008 #define IO_DISABLE 0x00C #define IO_CURRENT 0x020 #define IO_RESET 0x028 #define IO_MAX_PRIOTY 0x02C #define IO_IRQ_BASE 0x000 #define IO_FIQ_BASE 0x100 #define IO_INVERT_SEL 0x200 #define IO_STICKY_SEL 0x204 #define IO_PRIORITY_SEL 0x300 #define MAX_INTRS 32 #define FIQ_START MAX_INTRS static struct irq_domain *zevio_irq_domain; static void __iomem *zevio_irq_io; static void zevio_irq_ack(struct irq_data *irqd) { struct irq_chip_generic *gc = irq_data_get_irq_chip_data(irqd); struct irq_chip_regs *regs = &irq_data_get_chip_type(irqd)->regs; readl(gc->reg_base + regs->ack); } static void __exception_irq_entry zevio_handle_irq(struct pt_regs *regs) { int irqnr; while (readl(zevio_irq_io + IO_STATUS)) { irqnr = readl(zevio_irq_io + IO_CURRENT); handle_domain_irq(zevio_irq_domain, irqnr, regs); }; } static void __init zevio_init_irq_base(void __iomem *base) { /* Disable all interrupts */ writel(~0, base + IO_DISABLE); /* Accept interrupts of all priorities */ writel(0xF, base + IO_MAX_PRIOTY); /* Reset existing interrupts */ readl(base + IO_RESET); } static int __init zevio_of_init(struct device_node *node, struct device_node *parent) { unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN; struct irq_chip_generic *gc; int ret; if (WARN_ON(zevio_irq_io || zevio_irq_domain)) return -EBUSY; zevio_irq_io = of_iomap(node, 0); BUG_ON(!zevio_irq_io); /* Do not invert interrupt status bits */ writel(~0, zevio_irq_io + IO_INVERT_SEL); /* Disable sticky interrupts */ writel(0, zevio_irq_io + IO_STICKY_SEL); /* We don't use IRQ priorities. Set each IRQ to highest priority. */ memset_io(zevio_irq_io + IO_PRIORITY_SEL, 0, MAX_INTRS * sizeof(u32)); /* Init IRQ and FIQ */ zevio_init_irq_base(zevio_irq_io + IO_IRQ_BASE); zevio_init_irq_base(zevio_irq_io + IO_FIQ_BASE); zevio_irq_domain = irq_domain_add_linear(node, MAX_INTRS, &irq_generic_chip_ops, NULL); BUG_ON(!zevio_irq_domain); ret = irq_alloc_domain_generic_chips(zevio_irq_domain, MAX_INTRS, 1, "zevio_intc", handle_level_irq, clr, 0, IRQ_GC_INIT_MASK_CACHE); BUG_ON(ret); gc = irq_get_domain_generic_chip(zevio_irq_domain, 0); gc->reg_base = zevio_irq_io; gc->chip_types[0].chip.irq_ack = zevio_irq_ack; gc->chip_types[0].chip.irq_mask = irq_gc_mask_disable_reg; gc->chip_types[0].chip.irq_unmask = irq_gc_unmask_enable_reg; gc->chip_types[0].regs.mask = IO_IRQ_BASE + IO_ENABLE; gc->chip_types[0].regs.enable = IO_IRQ_BASE + IO_ENABLE; gc->chip_types[0].regs.disable = IO_IRQ_BASE + IO_DISABLE; gc->chip_types[0].regs.ack = IO_IRQ_BASE + IO_RESET; set_handle_irq(zevio_handle_irq); pr_info("TI-NSPIRE classic IRQ controller\n"); return 0; } IRQCHIP_DECLARE(zevio_irq, "lsi,zevio-intc", zevio_of_init);