openwrtv4/target/linux/oxnas/files/drivers/irqchip/irq-rps.c
John Crispin 26329f650c oxnas: prepare irqchip driver for kernel >=4.2
Signed-off-by: Daniel Golle <daniel@makrotopia.org>

SVN-Revision: 47216
2015-10-19 10:09:23 +00:00

163 lines
3.7 KiB
C

#include <linux/irqdomain.h>
#include <linux/irq.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/version.h>
#if LINUX_VERSION_CODE < KERNEL_VERSION(4,2,0)
# include "irqchip.h"
#else
# include <linux/irqchip.h>
#endif
struct rps_chip_data {
void __iomem *base;
struct irq_chip chip;
struct irq_domain *domain;
} rps_data;
enum {
RPS_IRQ_BASE = 64,
RPS_IRQ_COUNT = 32,
PRS_HWIRQ_BASE = 0,
RPS_STATUS = 0,
RPS_RAW_STATUS = 4,
RPS_UNMASK = 8,
RPS_MASK = 0xc,
};
/*
* Routines to acknowledge, disable and enable interrupts
*/
static void rps_mask_irq(struct irq_data *d)
{
struct rps_chip_data *chip_data = irq_data_get_irq_chip_data(d);
u32 mask = BIT(d->hwirq);
iowrite32(mask, chip_data->base + RPS_MASK);
}
static void rps_unmask_irq(struct irq_data *d)
{
struct rps_chip_data *chip_data = irq_data_get_irq_chip_data(d);
u32 mask = BIT(d->hwirq);
iowrite32(mask, chip_data->base + RPS_UNMASK);
}
static struct irq_chip rps_chip = {
.name = "RPS",
.irq_mask = rps_mask_irq,
.irq_unmask = rps_unmask_irq,
};
static int rps_irq_domain_xlate(struct irq_domain *d,
struct device_node *controller,
const u32 *intspec, unsigned int intsize,
unsigned long *out_hwirq,
unsigned int *out_type)
{
if (d->of_node != controller)
return -EINVAL;
if (intsize < 1)
return -EINVAL;
*out_hwirq = intspec[0];
/* Honestly I do not know the type */
*out_type = IRQ_TYPE_LEVEL_HIGH;
return 0;
}
static int rps_irq_domain_map(struct irq_domain *d, unsigned int irq,
irq_hw_number_t hw)
{
irq_set_chip_and_handler(irq, &rps_chip, handle_level_irq);
#if LINUX_VERSION_CODE < KERNEL_VERSION(4,2,0)
set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
#else
irq_set_probe(irq);
#endif
irq_set_chip_data(irq, d->host_data);
return 0;
}
const struct irq_domain_ops rps_irq_domain_ops = {
.map = rps_irq_domain_map,
.xlate = rps_irq_domain_xlate,
};
#if LINUX_VERSION_CODE < KERNEL_VERSION(4,2,0)
static void rps_handle_cascade_irq(unsigned int irq, struct irq_desc *desc)
#else
static void rps_handle_cascade_irq(struct irq_desc *desc)
#endif
{
struct rps_chip_data *chip_data = irq_desc_get_handler_data(desc);
struct irq_chip *chip = irq_desc_get_chip(desc);
unsigned int cascade_irq, rps_irq;
u32 status;
chained_irq_enter(chip, desc);
status = ioread32(chip_data->base + RPS_STATUS);
rps_irq = __ffs(status);
cascade_irq = irq_find_mapping(chip_data->domain, rps_irq);
if (unlikely(rps_irq >= RPS_IRQ_COUNT))
#if LINUX_VERSION_CODE < KERNEL_VERSION(4,2,0)
handle_bad_irq(cascade_irq, desc);
#else
handle_bad_irq(desc);
#endif
else
generic_handle_irq(cascade_irq);
chained_irq_exit(chip, desc);
}
#ifdef CONFIG_OF
int __init rps_of_init(struct device_node *node, struct device_node *parent)
{
void __iomem *rps_base;
int irq_start = RPS_IRQ_BASE;
int irq_base;
int irq;
if (WARN_ON(!node))
return -ENODEV;
rps_base = of_iomap(node, 0);
WARN(!rps_base, "unable to map rps registers\n");
rps_data.base = rps_base;
irq_base = irq_alloc_descs(irq_start, 0, RPS_IRQ_COUNT, numa_node_id());
if (IS_ERR_VALUE(irq_base)) {
WARN(1, "Cannot allocate irq_descs @ IRQ%d, assuming pre-allocated\n",
irq_start);
irq_base = irq_start;
}
rps_data.domain = irq_domain_add_legacy(node, RPS_IRQ_COUNT, irq_base,
PRS_HWIRQ_BASE, &rps_irq_domain_ops, &rps_data);
if (WARN_ON(!rps_data.domain))
return -ENOMEM;
if (parent) {
irq = irq_of_parse_and_map(node, 0);
if (irq_set_handler_data(irq, &rps_data) != 0)
BUG();
irq_set_chained_handler(irq, rps_handle_cascade_irq);
}
return 0;
}
IRQCHIP_DECLARE(nas782x, "plxtech,nas782x-rps", rps_of_init);
#endif