swh:1:snp:3c665ee4f67729f27f2e40193ab88e7298cf0fef
Tip revision: 422bef879e84104fee6dc68ded0e371dbeb5f88e authored by Linus Torvalds on 22 August 2009, 01:00:46 UTC
Linux 2.6.31-rc7
Linux 2.6.31-rc7
Tip revision: 422bef8
irq.c
/*
* linux/arch/arm/mach-omap2/irq.c
*
* Interrupt handler for OMAP2 boards.
*
* Copyright (C) 2005 Nokia Corporation
* Author: Paul Mundt <paul.mundt@nokia.com>
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <mach/hardware.h>
#include <asm/mach/irq.h>
/* selected INTC register offsets */
#define INTC_REVISION 0x0000
#define INTC_SYSCONFIG 0x0010
#define INTC_SYSSTATUS 0x0014
#define INTC_SIR 0x0040
#define INTC_CONTROL 0x0048
#define INTC_MIR_CLEAR0 0x0088
#define INTC_MIR_SET0 0x008c
#define INTC_PENDING_IRQ0 0x0098
/* Number of IRQ state bits in each MIR register */
#define IRQ_BITS_PER_REG 32
/*
* OMAP2 has a number of different interrupt controllers, each interrupt
* controller is identified as its own "bank". Register definitions are
* fairly consistent for each bank, but not all registers are implemented
* for each bank.. when in doubt, consult the TRM.
*/
static struct omap_irq_bank {
void __iomem *base_reg;
unsigned int nr_irqs;
} __attribute__ ((aligned(4))) irq_banks[] = {
{
/* MPU INTC */
.base_reg = 0,
.nr_irqs = 96,
},
};
/* INTC bank register get/set */
static void intc_bank_write_reg(u32 val, struct omap_irq_bank *bank, u16 reg)
{
__raw_writel(val, bank->base_reg + reg);
}
static u32 intc_bank_read_reg(struct omap_irq_bank *bank, u16 reg)
{
return __raw_readl(bank->base_reg + reg);
}
static int previous_irq;
/*
* On 34xx we can get occasional spurious interrupts if the ack from
* an interrupt handler does not get posted before we unmask. Warn about
* the interrupt handlers that need to flush posted writes.
*/
static int omap_check_spurious(unsigned int irq)
{
u32 sir, spurious;
sir = intc_bank_read_reg(&irq_banks[0], INTC_SIR);
spurious = sir >> 7;
if (spurious) {
printk(KERN_WARNING "Spurious irq %i: 0x%08x, please flush "
"posted write for irq %i\n",
irq, sir, previous_irq);
return spurious;
}
return 0;
}
/* XXX: FIQ and additional INTC support (only MPU at the moment) */
static void omap_ack_irq(unsigned int irq)
{
intc_bank_write_reg(0x1, &irq_banks[0], INTC_CONTROL);
}
static void omap_mask_irq(unsigned int irq)
{
int offset = irq & (~(IRQ_BITS_PER_REG - 1));
if (cpu_is_omap34xx()) {
int spurious = 0;
/*
* INT_34XX_GPT12_IRQ is also the spurious irq. Maybe because
* it is the highest irq number?
*/
if (irq == INT_34XX_GPT12_IRQ)
spurious = omap_check_spurious(irq);
if (!spurious)
previous_irq = irq;
}
irq &= (IRQ_BITS_PER_REG - 1);
intc_bank_write_reg(1 << irq, &irq_banks[0], INTC_MIR_SET0 + offset);
}
static void omap_unmask_irq(unsigned int irq)
{
int offset = irq & (~(IRQ_BITS_PER_REG - 1));
irq &= (IRQ_BITS_PER_REG - 1);
intc_bank_write_reg(1 << irq, &irq_banks[0], INTC_MIR_CLEAR0 + offset);
}
static void omap_mask_ack_irq(unsigned int irq)
{
omap_mask_irq(irq);
omap_ack_irq(irq);
}
static struct irq_chip omap_irq_chip = {
.name = "INTC",
.ack = omap_mask_ack_irq,
.mask = omap_mask_irq,
.unmask = omap_unmask_irq,
};
static void __init omap_irq_bank_init_one(struct omap_irq_bank *bank)
{
unsigned long tmp;
tmp = intc_bank_read_reg(bank, INTC_REVISION) & 0xff;
printk(KERN_INFO "IRQ: Found an INTC at 0x%p "
"(revision %ld.%ld) with %d interrupts\n",
bank->base_reg, tmp >> 4, tmp & 0xf, bank->nr_irqs);
tmp = intc_bank_read_reg(bank, INTC_SYSCONFIG);
tmp |= 1 << 1; /* soft reset */
intc_bank_write_reg(tmp, bank, INTC_SYSCONFIG);
while (!(intc_bank_read_reg(bank, INTC_SYSSTATUS) & 0x1))
/* Wait for reset to complete */;
/* Enable autoidle */
intc_bank_write_reg(1 << 0, bank, INTC_SYSCONFIG);
}
int omap_irq_pending(void)
{
int i;
for (i = 0; i < ARRAY_SIZE(irq_banks); i++) {
struct omap_irq_bank *bank = irq_banks + i;
int irq;
for (irq = 0; irq < bank->nr_irqs; irq += 32)
if (intc_bank_read_reg(bank, INTC_PENDING_IRQ0 +
((irq >> 5) << 5)))
return 1;
}
return 0;
}
void __init omap_init_irq(void)
{
unsigned long nr_of_irqs = 0;
unsigned int nr_banks = 0;
int i;
for (i = 0; i < ARRAY_SIZE(irq_banks); i++) {
struct omap_irq_bank *bank = irq_banks + i;
if (cpu_is_omap24xx())
bank->base_reg = OMAP2_IO_ADDRESS(OMAP24XX_IC_BASE);
else if (cpu_is_omap34xx())
bank->base_reg = OMAP2_IO_ADDRESS(OMAP34XX_IC_BASE);
omap_irq_bank_init_one(bank);
nr_of_irqs += bank->nr_irqs;
nr_banks++;
}
printk(KERN_INFO "Total of %ld interrupts on %d active controller%s\n",
nr_of_irqs, nr_banks, nr_banks > 1 ? "s" : "");
for (i = 0; i < nr_of_irqs; i++) {
set_irq_chip(i, &omap_irq_chip);
set_irq_handler(i, handle_level_irq);
set_irq_flags(i, IRQF_VALID);
}
}