1 // SPDX-License-Identifier: GPL-2.0
3 * Driver for IDT/Renesas 79RC3243x Interrupt Controller.
6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8 #include <linux/interrupt.h>
10 #include <linux/irqchip.h>
11 #include <linux/irqchip/chained_irq.h>
12 #include <linux/irqdomain.h>
13 #include <linux/of_address.h>
14 #include <linux/of_irq.h>
16 #define IDT_PIC_NR_IRQS 32
18 #define IDT_PIC_IRQ_PEND 0x00
19 #define IDT_PIC_IRQ_MASK 0x08
23 struct irq_domain *irq_domain;
24 struct irq_chip_generic *gc;
27 static void idt_irq_dispatch(struct irq_desc *desc)
29 struct idt_pic_data *idtpic = irq_desc_get_handler_data(desc);
30 struct irq_chip *host_chip = irq_desc_get_chip(desc);
31 u32 pending, hwirq, virq;
33 chained_irq_enter(host_chip, desc);
35 pending = irq_reg_readl(idtpic->gc, IDT_PIC_IRQ_PEND);
36 pending &= ~idtpic->gc->mask_cache;
38 hwirq = __fls(pending);
39 virq = irq_linear_revmap(idtpic->irq_domain, hwirq);
41 generic_handle_irq(virq);
42 pending &= ~(1 << hwirq);
45 chained_irq_exit(host_chip, desc);
48 static int idt_pic_init(struct device_node *of_node, struct device_node *parent)
50 struct irq_domain *domain;
51 struct idt_pic_data *idtpic;
52 struct irq_chip_generic *gc;
53 struct irq_chip_type *ct;
54 unsigned int parent_irq;
57 idtpic = kzalloc(sizeof(*idtpic), GFP_KERNEL);
63 parent_irq = irq_of_parse_and_map(of_node, 0);
65 pr_err("Failed to map parent IRQ!\n");
70 idtpic->base = of_iomap(of_node, 0);
72 pr_err("Failed to map base address!\n");
77 domain = irq_domain_add_linear(of_node, IDT_PIC_NR_IRQS,
78 &irq_generic_chip_ops, NULL);
80 pr_err("Failed to add irqdomain!\n");
84 idtpic->irq_domain = domain;
86 ret = irq_alloc_domain_generic_chips(domain, 32, 1, "IDTPIC",
88 IRQ_NOPROBE | IRQ_LEVEL, 0);
90 goto out_domain_remove;
92 gc = irq_get_domain_generic_chip(domain, 0);
93 gc->reg_base = idtpic->base;
97 ct->regs.mask = IDT_PIC_IRQ_MASK;
98 ct->chip.irq_mask = irq_gc_mask_set_bit;
99 ct->chip.irq_unmask = irq_gc_mask_clr_bit;
102 /* Mask interrupts. */
103 writel(0xffffffff, idtpic->base + IDT_PIC_IRQ_MASK);
104 gc->mask_cache = 0xffffffff;
106 irq_set_chained_handler_and_data(parent_irq,
107 idt_irq_dispatch, idtpic);
112 irq_domain_remove(domain);
114 iounmap(idtpic->base);
116 irq_dispose_mapping(parent_irq);
120 pr_err("Failed to initialize! (errno = %d)\n", ret);
124 IRQCHIP_DECLARE(idt_pic, "idt,32434-pic", idt_pic_init);