/* * arch/arm/mach-ns9xxx/irq.c * * Copyright (C) 2006,2007 by Digi International Inc. * All rights reserved. * * 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/interrupt.h> #include <linux/kernel_stat.h> #include <linux/io.h> #include <asm/mach/irq.h> #include <mach/regs-sys-common.h> #include <mach/irqs.h> #include <mach/board.h> #include "generic.h" /* simple interrupt prio table: prio(x) < prio(y) <=> x < y */ #define irq2prio(i) (i) #define prio2irq(p) (p) static void ns9xxx_mask_irq(unsigned int irq) { /* XXX: better use cpp symbols */ int prio = irq2prio(irq); u32 ic = __raw_readl(SYS_IC(prio / 4)); ic &= ~(1 << (7 + 8 * (3 - (prio & 3)))); __raw_writel(ic, SYS_IC(prio / 4)); } static void ns9xxx_ack_irq(unsigned int irq) { __raw_writel(0, SYS_ISRADDR); } static void ns9xxx_maskack_irq(unsigned int irq) { ns9xxx_mask_irq(irq); ns9xxx_ack_irq(irq); } static void ns9xxx_unmask_irq(unsigned int irq) { /* XXX: better use cpp symbols */ int prio = irq2prio(irq); u32 ic = __raw_readl(SYS_IC(prio / 4)); ic |= 1 << (7 + 8 * (3 - (prio & 3))); __raw_writel(ic, SYS_IC(prio / 4)); } static struct irq_chip ns9xxx_chip = { .ack = ns9xxx_ack_irq, .mask = ns9xxx_mask_irq, .mask_ack = ns9xxx_maskack_irq, .unmask = ns9xxx_unmask_irq, }; #if 0 #define handle_irq handle_level_irq #else static void handle_prio_irq(unsigned int irq, struct irq_desc *desc) { struct irqaction *action; irqreturn_t action_ret; raw_spin_lock(&desc->lock); BUG_ON(desc->status & IRQ_INPROGRESS); desc->status &= ~(IRQ_REPLAY | IRQ_WAITING); kstat_incr_irqs_this_cpu(irq, desc); action = desc->action; if (unlikely(!action || (desc->status & IRQ_DISABLED))) goto out_mask; desc->status |= IRQ_INPROGRESS; raw_spin_unlock(&desc->lock); action_ret = handle_IRQ_event(irq, action); /* XXX: There is no direct way to access noirqdebug, so check * unconditionally for spurious irqs... * Maybe this function should go to kernel/irq/chip.c? */ note_interrupt(irq, desc, action_ret); raw_spin_lock(&desc->lock); desc->status &= ~IRQ_INPROGRESS; if (desc->status & IRQ_DISABLED) out_mask: desc->chip->mask(irq); /* ack unconditionally to unmask lower prio irqs */ desc->chip->ack(irq); raw_spin_unlock(&desc->lock); } #define handle_irq handle_prio_irq #endif void __init ns9xxx_init_irq(void) { int i; /* disable all IRQs */ for (i = 0; i < 8; ++i) __raw_writel(prio2irq(4 * i) << 24 | prio2irq(4 * i + 1) << 16 | prio2irq(4 * i + 2) << 8 | prio2irq(4 * i + 3), SYS_IC(i)); for (i = 0; i < 32; ++i) __raw_writel(prio2irq(i), SYS_IVA(i)); for (i = 0; i <= 31; ++i) { set_irq_chip(i, &ns9xxx_chip); set_irq_handler(i, handle_irq); set_irq_flags(i, IRQF_VALID); } }