linux/drivers/irqchip/spear-shirq.c
Thomas Gleixner 97dcc21bd3 irqchip: spear_shirq: Kill the clear_reg nonsense
None of the chips has a ACK register. The code brainlessly fiddles
with the enable register, so it might even reenable a disabled
interrupt at least on spear300.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20140619212713.570396433@linutronix.de
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-06-24 12:38:07 +00:00

337 lines
7.8 KiB
C

/*
* SPEAr platform shared irq layer source file
*
* Copyright (C) 2009-2012 ST Microelectronics
* Viresh Kumar <viresh.linux@gmail.com>
*
* Copyright (C) 2012 ST Microelectronics
* Shiraz Hashim <shiraz.linux.kernel@gmail.com>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/err.h>
#include <linux/export.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/spinlock.h>
#include "irqchip.h"
/*
* struct shirq_regs: shared irq register configuration
*
* enb_reg: enable register offset
* reset_to_enb: val 1 indicates, we need to clear bit for enabling interrupt
* status_reg: status register offset
* status_reg_mask: status register valid mask
*/
struct shirq_regs {
u32 enb_reg;
u32 reset_to_enb;
u32 status_reg;
};
/*
* struct spear_shirq: shared irq structure
*
* base: Base register address
* regs: Register configuration for shared irq block
* mask: Mask to apply to the status register
* virq_base: Base virtual interrupt number
* nr_irqs: Number of interrupts handled by this block
* offset: Bit offset of the first interrupt
* disabled: Group is disabled, but accounted
*/
struct spear_shirq {
void __iomem *base;
struct shirq_regs regs;
u32 mask;
u32 virq_base;
u32 nr_irqs;
u32 offset;
bool disabled;
};
static DEFINE_SPINLOCK(lock);
/* spear300 shared irq registers offsets and masks */
#define SPEAR300_INT_ENB_MASK_REG 0x54
#define SPEAR300_INT_STS_MASK_REG 0x58
static struct spear_shirq spear300_shirq_ras1 = {
.offset = 0,
.nr_irqs = 9,
.mask = ((0x1 << 9) - 1) << 0,
.regs = {
.enb_reg = SPEAR300_INT_ENB_MASK_REG,
.status_reg = SPEAR300_INT_STS_MASK_REG,
},
};
static struct spear_shirq *spear300_shirq_blocks[] = {
&spear300_shirq_ras1,
};
/* spear310 shared irq registers offsets and masks */
#define SPEAR310_INT_STS_MASK_REG 0x04
static struct spear_shirq spear310_shirq_ras1 = {
.offset = 0,
.nr_irqs = 8,
.mask = ((0x1 << 8) - 1) << 0,
.regs = {
.enb_reg = -1,
.status_reg = SPEAR310_INT_STS_MASK_REG,
},
};
static struct spear_shirq spear310_shirq_ras2 = {
.offset = 8,
.nr_irqs = 5,
.mask = ((0x1 << 5) - 1) << 8,
.regs = {
.enb_reg = -1,
.status_reg = SPEAR310_INT_STS_MASK_REG,
},
};
static struct spear_shirq spear310_shirq_ras3 = {
.offset = 13,
.nr_irqs = 1,
.mask = ((0x1 << 1) - 1) << 13,
.regs = {
.enb_reg = -1,
.status_reg = SPEAR310_INT_STS_MASK_REG,
},
};
static struct spear_shirq spear310_shirq_intrcomm_ras = {
.offset = 14,
.nr_irqs = 3,
.mask = ((0x1 << 3) - 1) << 14,
.regs = {
.enb_reg = -1,
.status_reg = SPEAR310_INT_STS_MASK_REG,
},
};
static struct spear_shirq *spear310_shirq_blocks[] = {
&spear310_shirq_ras1,
&spear310_shirq_ras2,
&spear310_shirq_ras3,
&spear310_shirq_intrcomm_ras,
};
/* spear320 shared irq registers offsets and masks */
#define SPEAR320_INT_STS_MASK_REG 0x04
#define SPEAR320_INT_CLR_MASK_REG 0x04
#define SPEAR320_INT_ENB_MASK_REG 0x08
static struct spear_shirq spear320_shirq_ras3 = {
.offset = 0,
.nr_irqs = 7,
.mask = ((0x1 << 7) - 1) << 0,
.disabled = 1,
};
static struct spear_shirq spear320_shirq_ras1 = {
.offset = 7,
.nr_irqs = 3,
.mask = ((0x1 << 3) - 1) << 7,
.regs = {
.enb_reg = -1,
.status_reg = SPEAR320_INT_STS_MASK_REG,
},
};
static struct spear_shirq spear320_shirq_ras2 = {
.offset = 10,
.nr_irqs = 1,
.mask = ((0x1 << 1) - 1) << 10,
.regs = {
.enb_reg = -1,
.status_reg = SPEAR320_INT_STS_MASK_REG,
},
};
static struct spear_shirq spear320_shirq_intrcomm_ras = {
.offset = 11,
.nr_irqs = 11,
.mask = ((0x1 << 11) - 1) << 11,
.regs = {
.enb_reg = -1,
.status_reg = SPEAR320_INT_STS_MASK_REG,
},
};
static struct spear_shirq *spear320_shirq_blocks[] = {
&spear320_shirq_ras3,
&spear320_shirq_ras1,
&spear320_shirq_ras2,
&spear320_shirq_intrcomm_ras,
};
static void shirq_irq_mask_unmask(struct irq_data *d, bool mask)
{
struct spear_shirq *shirq = irq_data_get_irq_chip_data(d);
u32 val, offset = d->irq - shirq->virq_base;
unsigned long flags;
if (shirq->regs.enb_reg == -1)
return;
spin_lock_irqsave(&lock, flags);
val = readl(shirq->base + shirq->regs.enb_reg);
if (mask ^ shirq->regs.reset_to_enb)
val &= ~(0x1 << shirq->offset << offset);
else
val |= 0x1 << shirq->offset << offset;
writel(val, shirq->base + shirq->regs.enb_reg);
spin_unlock_irqrestore(&lock, flags);
}
static void shirq_irq_mask(struct irq_data *d)
{
shirq_irq_mask_unmask(d, 1);
}
static void shirq_irq_unmask(struct irq_data *d)
{
shirq_irq_mask_unmask(d, 0);
}
static struct irq_chip shirq_chip = {
.name = "spear-shirq",
.irq_ack = shirq_irq_mask,
.irq_mask = shirq_irq_mask,
.irq_unmask = shirq_irq_unmask,
};
static void shirq_handler(unsigned irq, struct irq_desc *desc)
{
struct spear_shirq *shirq = irq_get_handler_data(irq);
struct irq_data *idata = irq_desc_get_irq_data(desc);
struct irq_chip *chip = irq_data_get_irq_chip(idata);
u32 i, j, val, mask;
chip->irq_ack(idata);
mask = shirq->mask;
while ((val = readl(shirq->base + shirq->regs.status_reg) &
mask)) {
val >>= shirq->offset;
for (i = 0, j = 1; i < shirq->nr_irqs; i++, j <<= 1) {
if (!(j & val))
continue;
generic_handle_irq(shirq->virq_base + i);
}
}
chip->irq_unmask(idata);
}
static void __init spear_shirq_register(struct spear_shirq *shirq,
int parent_irq)
{
int i;
if (shirq->disabled)
return;
irq_set_chained_handler(parent_irq, shirq_handler);
irq_set_handler_data(parent_irq, shirq);
for (i = 0; i < shirq->nr_irqs; i++) {
irq_set_chip_and_handler(shirq->virq_base + i,
&shirq_chip, handle_simple_irq);
set_irq_flags(shirq->virq_base + i, IRQF_VALID);
irq_set_chip_data(shirq->virq_base + i, shirq);
}
}
static int __init shirq_init(struct spear_shirq **shirq_blocks, int block_nr,
struct device_node *np)
{
int i, parent_irq, virq_base, hwirq = 0, nr_irqs = 0;
struct irq_domain *shirq_domain;
void __iomem *base;
base = of_iomap(np, 0);
if (!base) {
pr_err("%s: failed to map shirq registers\n", __func__);
return -ENXIO;
}
for (i = 0; i < block_nr; i++)
nr_irqs += shirq_blocks[i]->nr_irqs;
virq_base = irq_alloc_descs(-1, 0, nr_irqs, 0);
if (IS_ERR_VALUE(virq_base)) {
pr_err("%s: irq desc alloc failed\n", __func__);
goto err_unmap;
}
shirq_domain = irq_domain_add_legacy(np, nr_irqs, virq_base, 0,
&irq_domain_simple_ops, NULL);
if (WARN_ON(!shirq_domain)) {
pr_warn("%s: irq domain init failed\n", __func__);
goto err_free_desc;
}
for (i = 0; i < block_nr; i++) {
shirq_blocks[i]->base = base;
shirq_blocks[i]->virq_base = irq_find_mapping(shirq_domain,
hwirq);
parent_irq = irq_of_parse_and_map(np, i);
spear_shirq_register(shirq_blocks[i], parent_irq);
hwirq += shirq_blocks[i]->nr_irqs;
}
return 0;
err_free_desc:
irq_free_descs(virq_base, nr_irqs);
err_unmap:
iounmap(base);
return -ENXIO;
}
static int __init spear300_shirq_of_init(struct device_node *np,
struct device_node *parent)
{
return shirq_init(spear300_shirq_blocks,
ARRAY_SIZE(spear300_shirq_blocks), np);
}
IRQCHIP_DECLARE(spear300_shirq, "st,spear300-shirq", spear300_shirq_of_init);
static int __init spear310_shirq_of_init(struct device_node *np,
struct device_node *parent)
{
return shirq_init(spear310_shirq_blocks,
ARRAY_SIZE(spear310_shirq_blocks), np);
}
IRQCHIP_DECLARE(spear310_shirq, "st,spear310-shirq", spear310_shirq_of_init);
static int __init spear320_shirq_of_init(struct device_node *np,
struct device_node *parent)
{
return shirq_init(spear320_shirq_blocks,
ARRAY_SIZE(spear320_shirq_blocks), np);
}
IRQCHIP_DECLARE(spear320_shirq, "st,spear320-shirq", spear320_shirq_of_init);