linux/arch/c6x/kernel/irq.c
Mark Salter f84f1f462b C6X: remove dependence on legacy IRQs
The core priority PIC code uses legacy irq support to facilitate direct
mapping of core hw interrupt numbers to linux interrupt numbers. This
patch removes the legacy irq usage and replaces it with a generic linear
mapping.

Signed-off-by: Mark Salter <msalter@redhat.com>
2012-07-18 23:49:40 -04:00

132 lines
3.1 KiB
C

/*
* Copyright (C) 2011-2012 Texas Instruments Incorporated
*
* This borrows heavily from powerpc version, which is:
*
* Derived from arch/i386/kernel/irq.c
* Copyright (C) 1992 Linus Torvalds
* Adapted from arch/i386 by Gary Thomas
* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
* Updated and modified by Cort Dougan <cort@fsmlabs.com>
* Copyright (C) 1996-2001 Cort Dougan
* Adapted for Power Macintosh by Paul Mackerras
* Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/slab.h>
#include <linux/seq_file.h>
#include <linux/radix-tree.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <asm/megamod-pic.h>
#include <asm/special_insns.h>
unsigned long irq_err_count;
static DEFINE_RAW_SPINLOCK(core_irq_lock);
static void mask_core_irq(struct irq_data *data)
{
unsigned int prio = data->hwirq;
raw_spin_lock(&core_irq_lock);
and_creg(IER, ~(1 << prio));
raw_spin_unlock(&core_irq_lock);
}
static void unmask_core_irq(struct irq_data *data)
{
unsigned int prio = data->hwirq;
raw_spin_lock(&core_irq_lock);
or_creg(IER, 1 << prio);
raw_spin_unlock(&core_irq_lock);
}
static struct irq_chip core_chip = {
.name = "core",
.irq_mask = mask_core_irq,
.irq_unmask = unmask_core_irq,
};
static int prio_to_virq[NR_PRIORITY_IRQS];
asmlinkage void c6x_do_IRQ(unsigned int prio, struct pt_regs *regs)
{
struct pt_regs *old_regs = set_irq_regs(regs);
irq_enter();
generic_handle_irq(prio_to_virq[prio]);
irq_exit();
set_irq_regs(old_regs);
}
static struct irq_domain *core_domain;
static int core_domain_map(struct irq_domain *h, unsigned int virq,
irq_hw_number_t hw)
{
if (hw < 4 || hw >= NR_PRIORITY_IRQS)
return -EINVAL;
prio_to_virq[hw] = virq;
irq_set_status_flags(virq, IRQ_LEVEL);
irq_set_chip_and_handler(virq, &core_chip, handle_level_irq);
return 0;
}
static const struct irq_domain_ops core_domain_ops = {
.map = core_domain_map,
.xlate = irq_domain_xlate_onecell,
};
void __init init_IRQ(void)
{
struct device_node *np;
/* Mask all priority IRQs */
and_creg(IER, ~0xfff0);
np = of_find_compatible_node(NULL, NULL, "ti,c64x+core-pic");
if (np != NULL) {
/* create the core host */
core_domain = irq_domain_add_linear(np, NR_PRIORITY_IRQS,
&core_domain_ops, NULL);
if (core_domain)
irq_set_default_host(core_domain);
of_node_put(np);
}
printk(KERN_INFO "Core interrupt controller initialized\n");
/* now we're ready for other SoC controllers */
megamod_pic_init();
/* Clear all general IRQ flags */
set_creg(ICR, 0xfff0);
}
void ack_bad_irq(int irq)
{
printk(KERN_ERR "IRQ: spurious interrupt %d\n", irq);
irq_err_count++;
}
int arch_show_interrupts(struct seq_file *p, int prec)
{
seq_printf(p, "%*s: %10lu\n", prec, "Err", irq_err_count);
return 0;
}