openwrt_archive/target/linux/mcs814x/files-3.18/arch/arm/mach-mcs814x/irq.c
John Crispin 5a856c26f5 mcs814x: fix interrupt handling
Switch to generich chip irqs/irq domains.
Interrupts were broken since kernel 3.14. dLAN USB extender is now
booting again.

Signed-off-by: Günther Kelleter <guenther.kelleter@devolo.de>

SVN-Revision: 46647
2015-08-17 06:16:08 +00:00

95 lines
2.3 KiB
C

/*
* Moschip MCS814x generic interrupt controller routines
*
* Copyright (C) 2012, Florian Fainelli <florian@openwrt.org>
*
* Licensed under the GPLv2
*/
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/irqdomain.h>
#include <asm/exception.h>
#include <asm/mach/irq.h>
#include <mach/mcs814x.h>
static void __iomem *mcs814x_intc_base;
static struct irq_domain *domain;
static void __init mcs814x_alloc_gc(void __iomem *base, unsigned int irq_start,
unsigned int num)
{
struct irq_chip_generic *gc;
struct irq_chip_type *ct;
if (irq_alloc_domain_generic_chips(domain, num, 1, "mcs814x-intc", handle_level_irq,
IRQ_GC_INIT_MASK_CACHE, IRQ_NOREQUEST, 0))
panic("unable to allocate domain generic irq chip");
gc = irq_get_domain_generic_chip(domain, irq_start);
if (!gc)
panic("unable to get generic irq chip");
gc->reg_base = base;
ct = gc->chip_types;
ct->chip.irq_ack = irq_gc_unmask_enable_reg;
ct->chip.irq_mask = irq_gc_mask_clr_bit;
ct->chip.irq_unmask = irq_gc_mask_set_bit;
ct->regs.mask = MCS814X_IRQ_MASK;
ct->regs.enable = MCS814X_IRQ_ICR;
/* Clear all interrupts */
writel_relaxed(0xffffffff, base + MCS814X_IRQ_ICR);
}
asmlinkage void __exception_irq_entry mcs814x_handle_irq(struct pt_regs *regs)
{
u32 status, irq;
do {
/* read the status register */
status = __raw_readl(mcs814x_intc_base + MCS814X_IRQ_STS0);
if (!status)
break;
irq = ffs(status) - 1;
status |= (1 << irq);
/* clear the interrupt */
__raw_writel(status, mcs814x_intc_base + MCS814X_IRQ_STS0);
/* call the generic handler */
handle_domain_irq(domain, irq, regs);
} while (1);
}
static const struct of_device_id mcs814x_intc_ids[] = {
{ .compatible = "moschip,mcs814x-intc" },
{ /* sentinel */ },
};
void __init mcs814x_of_irq_init(void)
{
struct device_node *np;
np = of_find_matching_node(NULL, mcs814x_intc_ids);
if (!np)
panic("unable to find compatible intc node in dtb\n");
mcs814x_intc_base = of_iomap(np, 0);
if (!mcs814x_intc_base)
panic("unable to map intc cpu registers\n");
domain = irq_domain_add_linear(np, 32, &irq_generic_chip_ops, NULL);
if (!domain)
panic("unable to add irq domain\n");
irq_set_default_host(domain);
of_node_put(np);
mcs814x_alloc_gc(mcs814x_intc_base, 0, 32);
}