2 * This program is free software; you can redistribute it and/or modify it
3 * under the terms of the GNU General Public License version 2 as published
4 * by the Free Software Foundation.
6 * Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org>
7 * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
11 #include <linux/bitops.h>
12 #include <linux/of_platform.h>
13 #include <linux/of_address.h>
14 #include <linux/of_irq.h>
15 #include <linux/irqdomain.h>
16 #include <linux/interrupt.h>
18 #include <asm/irq_cpu.h>
19 #include <asm/mipsregs.h>
23 /* INTC register offsets */
24 #define INTC_REG_STATUS0 0x00
25 #define INTC_REG_STATUS1 0x04
26 #define INTC_REG_TYPE 0x20
27 #define INTC_REG_RAW_STATUS 0x30
28 #define INTC_REG_ENABLE 0x34
29 #define INTC_REG_DISABLE 0x38
31 #define INTC_INT_GLOBAL BIT(31)
33 #define RALINK_CPU_IRQ_INTC (MIPS_CPU_IRQ_BASE + 2)
34 #define RALINK_CPU_IRQ_PCI (MIPS_CPU_IRQ_BASE + 4)
35 #define RALINK_CPU_IRQ_FE (MIPS_CPU_IRQ_BASE + 5)
36 #define RALINK_CPU_IRQ_WIFI (MIPS_CPU_IRQ_BASE + 6)
37 #define RALINK_CPU_IRQ_COUNTER (MIPS_CPU_IRQ_BASE + 7)
39 /* we have a cascade of 8 irqs */
40 #define RALINK_INTC_IRQ_BASE 8
42 /* we have 32 SoC irqs */
43 #define RALINK_INTC_IRQ_COUNT 32
45 #define RALINK_INTC_IRQ_PERFC (RALINK_INTC_IRQ_BASE + 9)
47 static void __iomem *rt_intc_membase;
48 static int rt_perfcount_irq;
50 static inline void rt_intc_w32(u32 val, unsigned reg)
52 __raw_writel(val, rt_intc_membase + reg);
55 static inline u32 rt_intc_r32(unsigned reg)
57 return __raw_readl(rt_intc_membase + reg);
60 static void ralink_intc_irq_unmask(struct irq_data *d)
62 rt_intc_w32(BIT(d->hwirq), INTC_REG_ENABLE);
65 static void ralink_intc_irq_mask(struct irq_data *d)
67 rt_intc_w32(BIT(d->hwirq), INTC_REG_DISABLE);
70 static struct irq_chip ralink_intc_irq_chip = {
72 .irq_unmask = ralink_intc_irq_unmask,
73 .irq_mask = ralink_intc_irq_mask,
74 .irq_mask_ack = ralink_intc_irq_mask,
77 int get_c0_perfcount_int(void)
79 return rt_perfcount_irq;
82 unsigned int get_c0_compare_int(void)
84 return CP0_LEGACY_COMPARE_IRQ;
87 static void ralink_intc_irq_handler(unsigned int irq, struct irq_desc *desc)
89 u32 pending = rt_intc_r32(INTC_REG_STATUS0);
92 struct irq_domain *domain = irq_get_handler_data(irq);
93 generic_handle_irq(irq_find_mapping(domain, __ffs(pending)));
99 asmlinkage void plat_irq_dispatch(void)
101 unsigned long pending;
103 pending = read_c0_status() & read_c0_cause() & ST0_IM;
105 if (pending & STATUSF_IP7)
106 do_IRQ(RALINK_CPU_IRQ_COUNTER);
108 else if (pending & STATUSF_IP5)
109 do_IRQ(RALINK_CPU_IRQ_FE);
111 else if (pending & STATUSF_IP6)
112 do_IRQ(RALINK_CPU_IRQ_WIFI);
114 else if (pending & STATUSF_IP4)
115 do_IRQ(RALINK_CPU_IRQ_PCI);
117 else if (pending & STATUSF_IP2)
118 do_IRQ(RALINK_CPU_IRQ_INTC);
121 spurious_interrupt();
124 static int intc_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw)
126 irq_set_chip_and_handler(irq, &ralink_intc_irq_chip, handle_level_irq);
131 static const struct irq_domain_ops irq_domain_ops = {
132 .xlate = irq_domain_xlate_onecell,
136 static int __init intc_of_init(struct device_node *node,
137 struct device_node *parent)
140 struct irq_domain *domain;
143 irq = irq_of_parse_and_map(node, 0);
145 panic("Failed to get INTC IRQ");
147 if (of_address_to_resource(node, 0, &res))
148 panic("Failed to get intc memory range");
150 if (request_mem_region(res.start, resource_size(&res),
152 pr_err("Failed to request intc memory");
154 rt_intc_membase = ioremap_nocache(res.start,
155 resource_size(&res));
156 if (!rt_intc_membase)
157 panic("Failed to remap intc memory");
159 /* disable all interrupts */
160 rt_intc_w32(~0, INTC_REG_DISABLE);
162 /* route all INTC interrupts to MIPS HW0 interrupt */
163 rt_intc_w32(0, INTC_REG_TYPE);
165 domain = irq_domain_add_legacy(node, RALINK_INTC_IRQ_COUNT,
166 RALINK_INTC_IRQ_BASE, 0, &irq_domain_ops, NULL);
168 panic("Failed to add irqdomain");
170 rt_intc_w32(INTC_INT_GLOBAL, INTC_REG_ENABLE);
172 irq_set_chained_handler(irq, ralink_intc_irq_handler);
173 irq_set_handler_data(irq, domain);
175 /* tell the kernel which irq is used for performance monitoring */
176 rt_perfcount_irq = irq_create_mapping(domain, 9);
181 static struct of_device_id __initdata of_irq_ids[] = {
182 { .compatible = "mti,cpu-interrupt-controller", .data = mips_cpu_irq_of_init },
183 { .compatible = "ralink,rt2880-intc", .data = intc_of_init },
187 void __init arch_init_irq(void)
189 of_irq_init(of_irq_ids);