kernel-ark/arch/nios2/kernel/irq.c
Ley Foon Tan f27ffc751c nios2: Interrupt handling
This patch adds the support for IRQ handling.

Signed-off-by: Ley Foon Tan <lftan@altera.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-08 12:55:55 +08:00

94 lines
2.3 KiB
C

/*
* Copyright (C) 2013 Altera Corporation
* Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
* Copyright (C) 2008 Thomas Chou <thomas@wytron.com.tw>
*
* based on irq.c from m68k which is:
*
* Copyright (C) 2007 Greg Ungerer <gerg@snapgear.com>
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/of.h>
static u32 ienable;
asmlinkage void do_IRQ(int hwirq, struct pt_regs *regs)
{
struct pt_regs *oldregs = set_irq_regs(regs);
int irq;
irq_enter();
irq = irq_find_mapping(NULL, hwirq);
generic_handle_irq(irq);
irq_exit();
set_irq_regs(oldregs);
}
static void chip_unmask(struct irq_data *d)
{
ienable |= (1 << d->hwirq);
WRCTL(CTL_IENABLE, ienable);
}
static void chip_mask(struct irq_data *d)
{
ienable &= ~(1 << d->hwirq);
WRCTL(CTL_IENABLE, ienable);
}
static struct irq_chip m_irq_chip = {
.name = "NIOS2-INTC",
.irq_unmask = chip_unmask,
.irq_mask = chip_mask,
};
static int irq_map(struct irq_domain *h, unsigned int virq,
irq_hw_number_t hw_irq_num)
{
irq_set_chip_and_handler(virq, &m_irq_chip, handle_level_irq);
return 0;
}
static struct irq_domain_ops irq_ops = {
.map = irq_map,
.xlate = irq_domain_xlate_onecell,
};
void __init init_IRQ(void)
{
struct irq_domain *domain;
struct device_node *node;
node = of_find_compatible_node(NULL, NULL, "altr,nios2-1.0");
if (!node)
node = of_find_compatible_node(NULL, NULL, "altr,nios2-1.1");
BUG_ON(!node);
domain = irq_domain_add_linear(node, NIOS2_CPU_NR_IRQS, &irq_ops, NULL);
BUG_ON(!domain);
irq_set_default_host(domain);
of_node_put(node);
/* Load the initial ienable value */
ienable = RDCTL(CTL_IENABLE);
}