linux-sg2042/drivers/irqchip/irq-sa11x0.c

175 lines
3.9 KiB
C

/*
* Copyright (C) 2015 Dmitry Eremin-Solenikov
* Copyright (C) 1999-2001 Nicolas Pitre
*
* Generic IRQ handling for the SA11x0.
*
* 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/init.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/syscore_ops.h>
#include <linux/irqchip/irq-sa11x0.h>
#include <soc/sa1100/pwer.h>
#include <asm/exception.h>
#define ICIP 0x00 /* IC IRQ Pending reg. */
#define ICMR 0x04 /* IC Mask Reg. */
#define ICLR 0x08 /* IC Level Reg. */
#define ICCR 0x0C /* IC Control Reg. */
#define ICFP 0x10 /* IC FIQ Pending reg. */
#define ICPR 0x20 /* IC Pending Reg. */
static void __iomem *iobase;
/*
* We don't need to ACK IRQs on the SA1100 unless they're GPIOs
* this is for internal IRQs i.e. from IRQ LCD to RTCAlrm.
*/
static void sa1100_mask_irq(struct irq_data *d)
{
u32 reg;
reg = readl_relaxed(iobase + ICMR);
reg &= ~BIT(d->hwirq);
writel_relaxed(reg, iobase + ICMR);
}
static void sa1100_unmask_irq(struct irq_data *d)
{
u32 reg;
reg = readl_relaxed(iobase + ICMR);
reg |= BIT(d->hwirq);
writel_relaxed(reg, iobase + ICMR);
}
static int sa1100_set_wake(struct irq_data *d, unsigned int on)
{
return sa11x0_sc_set_wake(d->hwirq, on);
}
static struct irq_chip sa1100_normal_chip = {
.name = "SC",
.irq_ack = sa1100_mask_irq,
.irq_mask = sa1100_mask_irq,
.irq_unmask = sa1100_unmask_irq,
.irq_set_wake = sa1100_set_wake,
};
static int sa1100_normal_irqdomain_map(struct irq_domain *d,
unsigned int irq, irq_hw_number_t hwirq)
{
irq_set_chip_and_handler(irq, &sa1100_normal_chip,
handle_level_irq);
return 0;
}
static const struct irq_domain_ops sa1100_normal_irqdomain_ops = {
.map = sa1100_normal_irqdomain_map,
.xlate = irq_domain_xlate_onetwocell,
};
static struct irq_domain *sa1100_normal_irqdomain;
static struct sa1100irq_state {
unsigned int saved;
unsigned int icmr;
unsigned int iclr;
unsigned int iccr;
} sa1100irq_state;
static int sa1100irq_suspend(void)
{
struct sa1100irq_state *st = &sa1100irq_state;
st->saved = 1;
st->icmr = readl_relaxed(iobase + ICMR);
st->iclr = readl_relaxed(iobase + ICLR);
st->iccr = readl_relaxed(iobase + ICCR);
/*
* Disable all GPIO-based interrupts.
*/
writel_relaxed(st->icmr & 0xfffff000, iobase + ICMR);
return 0;
}
static void sa1100irq_resume(void)
{
struct sa1100irq_state *st = &sa1100irq_state;
if (st->saved) {
writel_relaxed(st->iccr, iobase + ICCR);
writel_relaxed(st->iclr, iobase + ICLR);
writel_relaxed(st->icmr, iobase + ICMR);
}
}
static struct syscore_ops sa1100irq_syscore_ops = {
.suspend = sa1100irq_suspend,
.resume = sa1100irq_resume,
};
static int __init sa1100irq_init_devicefs(void)
{
register_syscore_ops(&sa1100irq_syscore_ops);
return 0;
}
device_initcall(sa1100irq_init_devicefs);
static asmlinkage void __exception_irq_entry
sa1100_handle_irq(struct pt_regs *regs)
{
uint32_t icip, icmr, mask;
do {
icip = readl_relaxed(iobase + ICIP);
icmr = readl_relaxed(iobase + ICMR);
mask = icip & icmr;
if (mask == 0)
break;
handle_domain_irq(sa1100_normal_irqdomain,
ffs(mask) - 1, regs);
} while (1);
}
void __init sa11x0_init_irq_nodt(int irq_start, resource_size_t io_start)
{
iobase = ioremap(io_start, SZ_64K);
if (WARN_ON(!iobase))
return;
/* disable all IRQs */
writel_relaxed(0, iobase + ICMR);
/* all IRQs are IRQ, not FIQ */
writel_relaxed(0, iobase + ICLR);
/*
* Whatever the doc says, this has to be set for the wait-on-irq
* instruction to work... on a SA1100 rev 9 at least.
*/
writel_relaxed(1, iobase + ICCR);
sa1100_normal_irqdomain = irq_domain_add_simple(NULL,
32, irq_start,
&sa1100_normal_irqdomain_ops, NULL);
set_handle_irq(sa1100_handle_irq);
}