1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * 4 * Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org> 5 * Copyright (C) 2013 John Crispin <john@phrozen.org> 6 */ 7 8 #include <linux/io.h> 9 #include <linux/bitops.h> 10 #include <linux/of_platform.h> 11 #include <linux/of_address.h> 12 #include <linux/of_irq.h> 13 #include <linux/irqdomain.h> 14 #include <linux/interrupt.h> 15 16 #include <asm/irq_cpu.h> 17 #include <asm/mipsregs.h> 18 19 #include "common.h" 20 21 #define INTC_INT_GLOBAL BIT(31) 22 23 #define RALINK_CPU_IRQ_INTC (MIPS_CPU_IRQ_BASE + 2) 24 #define RALINK_CPU_IRQ_PCI (MIPS_CPU_IRQ_BASE + 4) 25 #define RALINK_CPU_IRQ_FE (MIPS_CPU_IRQ_BASE + 5) 26 #define RALINK_CPU_IRQ_WIFI (MIPS_CPU_IRQ_BASE + 6) 27 #define RALINK_CPU_IRQ_COUNTER (MIPS_CPU_IRQ_BASE + 7) 28 29 /* we have a cascade of 8 irqs */ 30 #define RALINK_INTC_IRQ_BASE 8 31 32 /* we have 32 SoC irqs */ 33 #define RALINK_INTC_IRQ_COUNT 32 34 35 #define RALINK_INTC_IRQ_PERFC (RALINK_INTC_IRQ_BASE + 9) 36 37 enum rt_intc_regs_enum { 38 INTC_REG_STATUS0 = 0, 39 INTC_REG_STATUS1, 40 INTC_REG_TYPE, 41 INTC_REG_RAW_STATUS, 42 INTC_REG_ENABLE, 43 INTC_REG_DISABLE, 44 }; 45 46 static u32 rt_intc_regs[] = { 47 [INTC_REG_STATUS0] = 0x00, 48 [INTC_REG_STATUS1] = 0x04, 49 [INTC_REG_TYPE] = 0x20, 50 [INTC_REG_RAW_STATUS] = 0x30, 51 [INTC_REG_ENABLE] = 0x34, 52 [INTC_REG_DISABLE] = 0x38, 53 }; 54 55 static void __iomem *rt_intc_membase; 56 57 static int rt_perfcount_irq; 58 59 static inline void rt_intc_w32(u32 val, unsigned reg) 60 { 61 __raw_writel(val, rt_intc_membase + rt_intc_regs[reg]); 62 } 63 64 static inline u32 rt_intc_r32(unsigned reg) 65 { 66 return __raw_readl(rt_intc_membase + rt_intc_regs[reg]); 67 } 68 69 static void ralink_intc_irq_unmask(struct irq_data *d) 70 { 71 rt_intc_w32(BIT(d->hwirq), INTC_REG_ENABLE); 72 } 73 74 static void ralink_intc_irq_mask(struct irq_data *d) 75 { 76 rt_intc_w32(BIT(d->hwirq), INTC_REG_DISABLE); 77 } 78 79 static struct irq_chip ralink_intc_irq_chip = { 80 .name = "INTC", 81 .irq_unmask = ralink_intc_irq_unmask, 82 .irq_mask = ralink_intc_irq_mask, 83 .irq_mask_ack = ralink_intc_irq_mask, 84 }; 85 86 int get_c0_perfcount_int(void) 87 { 88 return rt_perfcount_irq; 89 } 90 EXPORT_SYMBOL_GPL(get_c0_perfcount_int); 91 92 unsigned int get_c0_compare_int(void) 93 { 94 return CP0_LEGACY_COMPARE_IRQ; 95 } 96 97 static void ralink_intc_irq_handler(struct irq_desc *desc) 98 { 99 u32 pending = rt_intc_r32(INTC_REG_STATUS0); 100 101 if (pending) { 102 struct irq_domain *domain = irq_desc_get_handler_data(desc); 103 generic_handle_irq(irq_find_mapping(domain, __ffs(pending))); 104 } else { 105 spurious_interrupt(); 106 } 107 } 108 109 asmlinkage void plat_irq_dispatch(void) 110 { 111 unsigned long pending; 112 113 pending = read_c0_status() & read_c0_cause() & ST0_IM; 114 115 if (pending & STATUSF_IP7) 116 do_IRQ(RALINK_CPU_IRQ_COUNTER); 117 118 else if (pending & STATUSF_IP5) 119 do_IRQ(RALINK_CPU_IRQ_FE); 120 121 else if (pending & STATUSF_IP6) 122 do_IRQ(RALINK_CPU_IRQ_WIFI); 123 124 else if (pending & STATUSF_IP4) 125 do_IRQ(RALINK_CPU_IRQ_PCI); 126 127 else if (pending & STATUSF_IP2) 128 do_IRQ(RALINK_CPU_IRQ_INTC); 129 130 else 131 spurious_interrupt(); 132 } 133 134 static int intc_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw) 135 { 136 irq_set_chip_and_handler(irq, &ralink_intc_irq_chip, handle_level_irq); 137 138 return 0; 139 } 140 141 static const struct irq_domain_ops irq_domain_ops = { 142 .xlate = irq_domain_xlate_onecell, 143 .map = intc_map, 144 }; 145 146 static int __init intc_of_init(struct device_node *node, 147 struct device_node *parent) 148 { 149 struct resource res; 150 struct irq_domain *domain; 151 int irq; 152 153 if (!of_property_read_u32_array(node, "ralink,intc-registers", 154 rt_intc_regs, 6)) 155 pr_info("intc: using register map from devicetree\n"); 156 157 irq = irq_of_parse_and_map(node, 0); 158 if (!irq) 159 panic("Failed to get INTC IRQ"); 160 161 if (of_address_to_resource(node, 0, &res)) 162 panic("Failed to get intc memory range"); 163 164 if (!request_mem_region(res.start, resource_size(&res), 165 res.name)) 166 pr_err("Failed to request intc memory"); 167 168 rt_intc_membase = ioremap(res.start, 169 resource_size(&res)); 170 if (!rt_intc_membase) 171 panic("Failed to remap intc memory"); 172 173 /* disable all interrupts */ 174 rt_intc_w32(~0, INTC_REG_DISABLE); 175 176 /* route all INTC interrupts to MIPS HW0 interrupt */ 177 rt_intc_w32(0, INTC_REG_TYPE); 178 179 domain = irq_domain_add_legacy(node, RALINK_INTC_IRQ_COUNT, 180 RALINK_INTC_IRQ_BASE, 0, &irq_domain_ops, NULL); 181 if (!domain) 182 panic("Failed to add irqdomain"); 183 184 rt_intc_w32(INTC_INT_GLOBAL, INTC_REG_ENABLE); 185 186 irq_set_chained_handler_and_data(irq, ralink_intc_irq_handler, domain); 187 188 /* tell the kernel which irq is used for performance monitoring */ 189 rt_perfcount_irq = irq_create_mapping(domain, 9); 190 191 return 0; 192 } 193 194 static struct of_device_id __initdata of_irq_ids[] = { 195 { .compatible = "mti,cpu-interrupt-controller", .data = mips_cpu_irq_of_init }, 196 { .compatible = "ralink,rt2880-intc", .data = intc_of_init }, 197 {}, 198 }; 199 200 void __init arch_init_irq(void) 201 { 202 of_irq_init(of_irq_ids); 203 } 204 205