linuxdebug/drivers/irqchip/irq-idt3243x.c

123 lines
2.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Driver for IDT/Renesas 79RC3243x Interrupt Controller.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/irqchip.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/irqdomain.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#define IDT_PIC_NR_IRQS 32
#define IDT_PIC_IRQ_PEND 0x00
#define IDT_PIC_IRQ_MASK 0x08
struct idt_pic_data {
void __iomem *base;
struct irq_domain *irq_domain;
struct irq_chip_generic *gc;
};
static void idt_irq_dispatch(struct irq_desc *desc)
{
struct idt_pic_data *idtpic = irq_desc_get_handler_data(desc);
struct irq_chip *host_chip = irq_desc_get_chip(desc);
u32 pending, hwirq;
chained_irq_enter(host_chip, desc);
pending = irq_reg_readl(idtpic->gc, IDT_PIC_IRQ_PEND);
pending &= ~idtpic->gc->mask_cache;
while (pending) {
hwirq = __fls(pending);
generic_handle_domain_irq(idtpic->irq_domain, hwirq);
pending &= ~(1 << hwirq);
}
chained_irq_exit(host_chip, desc);
}
static int idt_pic_init(struct device_node *of_node, struct device_node *parent)
{
struct irq_domain *domain;
struct idt_pic_data *idtpic;
struct irq_chip_generic *gc;
struct irq_chip_type *ct;
unsigned int parent_irq;
int ret = 0;
idtpic = kzalloc(sizeof(*idtpic), GFP_KERNEL);
if (!idtpic) {
ret = -ENOMEM;
goto out_err;
}
parent_irq = irq_of_parse_and_map(of_node, 0);
if (!parent_irq) {
pr_err("Failed to map parent IRQ!\n");
ret = -EINVAL;
goto out_free;
}
idtpic->base = of_iomap(of_node, 0);
if (!idtpic->base) {
pr_err("Failed to map base address!\n");
ret = -ENOMEM;
goto out_unmap_irq;
}
domain = irq_domain_add_linear(of_node, IDT_PIC_NR_IRQS,
&irq_generic_chip_ops, NULL);
if (!domain) {
pr_err("Failed to add irqdomain!\n");
ret = -ENOMEM;
goto out_iounmap;
}
idtpic->irq_domain = domain;
ret = irq_alloc_domain_generic_chips(domain, 32, 1, "IDTPIC",
handle_level_irq, 0,
IRQ_NOPROBE | IRQ_LEVEL, 0);
if (ret)
goto out_domain_remove;
gc = irq_get_domain_generic_chip(domain, 0);
gc->reg_base = idtpic->base;
gc->private = idtpic;
ct = gc->chip_types;
ct->regs.mask = IDT_PIC_IRQ_MASK;
ct->chip.irq_mask = irq_gc_mask_set_bit;
ct->chip.irq_unmask = irq_gc_mask_clr_bit;
idtpic->gc = gc;
/* Mask interrupts. */
writel(0xffffffff, idtpic->base + IDT_PIC_IRQ_MASK);
gc->mask_cache = 0xffffffff;
irq_set_chained_handler_and_data(parent_irq,
idt_irq_dispatch, idtpic);
return 0;
out_domain_remove:
irq_domain_remove(domain);
out_iounmap:
iounmap(idtpic->base);
out_unmap_irq:
irq_dispose_mapping(parent_irq);
out_free:
kfree(idtpic);
out_err:
pr_err("Failed to initialize! (errno = %d)\n", ret);
return ret;
}
IRQCHIP_DECLARE(idt_pic, "idt,32434-pic", idt_pic_init);