linux/arch/arm/mach-imx/avic.c
Uwe Kleine-König 81efe0fc67 ARM: imx: drop support for irq priorisation
The code for irq priorisation support doesn't have any in-tree users and
the Kconfig description does wrong promises because nowadays irq
handlers are called with irqs disabled, so no high prioritized irq can
interrupt a lower prioritized handler.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
2013-12-09 13:18:25 +08:00

200 lines
5.8 KiB
C

/*
* Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
* Copyright 2008 Juergen Beisert, kernel@pengutronix.de
*
* 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, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301, USA.
*/
#include <linux/module.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/io.h>
#include <linux/of.h>
#include <asm/mach/irq.h>
#include <asm/exception.h>
#include "common.h"
#include "hardware.h"
#include "irq-common.h"
#define AVIC_INTCNTL 0x00 /* int control reg */
#define AVIC_NIMASK 0x04 /* int mask reg */
#define AVIC_INTENNUM 0x08 /* int enable number reg */
#define AVIC_INTDISNUM 0x0C /* int disable number reg */
#define AVIC_INTENABLEH 0x10 /* int enable reg high */
#define AVIC_INTENABLEL 0x14 /* int enable reg low */
#define AVIC_INTTYPEH 0x18 /* int type reg high */
#define AVIC_INTTYPEL 0x1C /* int type reg low */
#define AVIC_NIPRIORITY(x) (0x20 + 4 * (7 - (x))) /* int priority */
#define AVIC_NIVECSR 0x40 /* norm int vector/status */
#define AVIC_FIVECSR 0x44 /* fast int vector/status */
#define AVIC_INTSRCH 0x48 /* int source reg high */
#define AVIC_INTSRCL 0x4C /* int source reg low */
#define AVIC_INTFRCH 0x50 /* int force reg high */
#define AVIC_INTFRCL 0x54 /* int force reg low */
#define AVIC_NIPNDH 0x58 /* norm int pending high */
#define AVIC_NIPNDL 0x5C /* norm int pending low */
#define AVIC_FIPNDH 0x60 /* fast int pending high */
#define AVIC_FIPNDL 0x64 /* fast int pending low */
#define AVIC_NUM_IRQS 64
static void __iomem *avic_base;
static struct irq_domain *domain;
#ifdef CONFIG_FIQ
static int avic_set_irq_fiq(unsigned int irq, unsigned int type)
{
struct irq_data *d = irq_get_irq_data(irq);
unsigned int irqt;
irq = d->hwirq;
if (irq >= AVIC_NUM_IRQS)
return -EINVAL;
if (irq < AVIC_NUM_IRQS / 2) {
irqt = __raw_readl(avic_base + AVIC_INTTYPEL) & ~(1 << irq);
__raw_writel(irqt | (!!type << irq), avic_base + AVIC_INTTYPEL);
} else {
irq -= AVIC_NUM_IRQS / 2;
irqt = __raw_readl(avic_base + AVIC_INTTYPEH) & ~(1 << irq);
__raw_writel(irqt | (!!type << irq), avic_base + AVIC_INTTYPEH);
}
return 0;
}
#endif /* CONFIG_FIQ */
static struct mxc_extra_irq avic_extra_irq = {
#ifdef CONFIG_FIQ
.set_irq_fiq = avic_set_irq_fiq,
#endif
};
#ifdef CONFIG_PM
static u32 avic_saved_mask_reg[2];
static void avic_irq_suspend(struct irq_data *d)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
struct irq_chip_type *ct = gc->chip_types;
int idx = d->hwirq >> 5;
avic_saved_mask_reg[idx] = __raw_readl(avic_base + ct->regs.mask);
__raw_writel(gc->wake_active, avic_base + ct->regs.mask);
}
static void avic_irq_resume(struct irq_data *d)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
struct irq_chip_type *ct = gc->chip_types;
int idx = d->hwirq >> 5;
__raw_writel(avic_saved_mask_reg[idx], avic_base + ct->regs.mask);
}
#else
#define avic_irq_suspend NULL
#define avic_irq_resume NULL
#endif
static __init void avic_init_gc(int idx, unsigned int irq_start)
{
struct irq_chip_generic *gc;
struct irq_chip_type *ct;
gc = irq_alloc_generic_chip("mxc-avic", 1, irq_start, avic_base,
handle_level_irq);
gc->private = &avic_extra_irq;
gc->wake_enabled = IRQ_MSK(32);
ct = gc->chip_types;
ct->chip.irq_mask = irq_gc_mask_clr_bit;
ct->chip.irq_unmask = irq_gc_mask_set_bit;
ct->chip.irq_ack = irq_gc_mask_clr_bit;
ct->chip.irq_set_wake = irq_gc_set_wake;
ct->chip.irq_suspend = avic_irq_suspend;
ct->chip.irq_resume = avic_irq_resume;
ct->regs.mask = !idx ? AVIC_INTENABLEL : AVIC_INTENABLEH;
ct->regs.ack = ct->regs.mask;
irq_setup_generic_chip(gc, IRQ_MSK(32), 0, IRQ_NOREQUEST, 0);
}
asmlinkage void __exception_irq_entry avic_handle_irq(struct pt_regs *regs)
{
u32 nivector;
do {
nivector = __raw_readl(avic_base + AVIC_NIVECSR) >> 16;
if (nivector == 0xffff)
break;
handle_IRQ(irq_find_mapping(domain, nivector), regs);
} while (1);
}
/*
* This function initializes the AVIC hardware and disables all the
* interrupts. It registers the interrupt enable and disable functions
* to the kernel for each interrupt source.
*/
void __init mxc_init_irq(void __iomem *irqbase)
{
struct device_node *np;
int irq_base;
int i;
avic_base = irqbase;
/* put the AVIC into the reset value with
* all interrupts disabled
*/
__raw_writel(0, avic_base + AVIC_INTCNTL);
__raw_writel(0x1f, avic_base + AVIC_NIMASK);
/* disable all interrupts */
__raw_writel(0, avic_base + AVIC_INTENABLEH);
__raw_writel(0, avic_base + AVIC_INTENABLEL);
/* all IRQ no FIQ */
__raw_writel(0, avic_base + AVIC_INTTYPEH);
__raw_writel(0, avic_base + AVIC_INTTYPEL);
irq_base = irq_alloc_descs(-1, 0, AVIC_NUM_IRQS, numa_node_id());
WARN_ON(irq_base < 0);
np = of_find_compatible_node(NULL, NULL, "fsl,avic");
domain = irq_domain_add_legacy(np, AVIC_NUM_IRQS, irq_base, 0,
&irq_domain_simple_ops, NULL);
WARN_ON(!domain);
for (i = 0; i < AVIC_NUM_IRQS / 32; i++, irq_base += 32)
avic_init_gc(i, irq_base);
/* Set default priority value (0) for all IRQ's */
for (i = 0; i < 8; i++)
__raw_writel(0, avic_base + AVIC_NIPRIORITY(i));
#ifdef CONFIG_FIQ
/* Initialize FIQ */
init_FIQ(FIQ_START);
#endif
printk(KERN_INFO "MXC IRQ initialized\n");
}