1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) 2 /* 3 * Copyright (C) Sunplus Technology Co., Ltd. 4 * All rights reserved. 5 */ 6 #include <linux/irq.h> 7 #include <linux/irqdomain.h> 8 #include <linux/io.h> 9 #include <linux/irqchip.h> 10 #include <linux/irqchip/chained_irq.h> 11 #include <linux/of_address.h> 12 #include <linux/of_irq.h> 13 14 #define SP_INTC_HWIRQ_MIN 0 15 #define SP_INTC_HWIRQ_MAX 223 16 17 #define SP_INTC_NR_IRQS (SP_INTC_HWIRQ_MAX - SP_INTC_HWIRQ_MIN + 1) 18 #define SP_INTC_NR_GROUPS DIV_ROUND_UP(SP_INTC_NR_IRQS, 32) 19 #define SP_INTC_REG_SIZE (SP_INTC_NR_GROUPS * 4) 20 21 /* REG_GROUP_0 regs */ 22 #define REG_INTR_TYPE (sp_intc.g0) 23 #define REG_INTR_POLARITY (REG_INTR_TYPE + SP_INTC_REG_SIZE) 24 #define REG_INTR_PRIORITY (REG_INTR_POLARITY + SP_INTC_REG_SIZE) 25 #define REG_INTR_MASK (REG_INTR_PRIORITY + SP_INTC_REG_SIZE) 26 27 /* REG_GROUP_1 regs */ 28 #define REG_INTR_CLEAR (sp_intc.g1) 29 #define REG_MASKED_EXT1 (REG_INTR_CLEAR + SP_INTC_REG_SIZE) 30 #define REG_MASKED_EXT0 (REG_MASKED_EXT1 + SP_INTC_REG_SIZE) 31 #define REG_INTR_GROUP (REG_INTR_CLEAR + 31 * 4) 32 33 #define GROUP_MASK (BIT(SP_INTC_NR_GROUPS) - 1) 34 #define GROUP_SHIFT_EXT1 (0) 35 #define GROUP_SHIFT_EXT0 (8) 36 37 /* 38 * When GPIO_INT0~7 set to edge trigger, doesn't work properly. 39 * WORKAROUND: change it to level trigger, and toggle the polarity 40 * at ACK/Handler to make the HW work. 41 */ 42 #define GPIO_INT0_HWIRQ 120 43 #define GPIO_INT7_HWIRQ 127 44 #define IS_GPIO_INT(irq) \ 45 ({ \ 46 u32 i = irq; \ 47 (i >= GPIO_INT0_HWIRQ) && (i <= GPIO_INT7_HWIRQ); \ 48 }) 49 50 /* index of states */ 51 enum { 52 _IS_EDGE = 0, 53 _IS_LOW, 54 _IS_ACTIVE 55 }; 56 57 #define STATE_BIT(irq, idx) (((irq) - GPIO_INT0_HWIRQ) * 3 + (idx)) 58 #define ASSIGN_STATE(irq, idx, v) assign_bit(STATE_BIT(irq, idx), sp_intc.states, v) 59 #define TEST_STATE(irq, idx) test_bit(STATE_BIT(irq, idx), sp_intc.states) 60 61 static struct sp_intctl { 62 /* 63 * REG_GROUP_0: include type/polarity/priority/mask regs. 64 * REG_GROUP_1: include clear/masked_ext0/masked_ext1/group regs. 65 */ 66 void __iomem *g0; // REG_GROUP_0 base 67 void __iomem *g1; // REG_GROUP_1 base 68 69 struct irq_domain *domain; 70 raw_spinlock_t lock; 71 72 /* 73 * store GPIO_INT states 74 * each interrupt has 3 states: is_edge, is_low, is_active 75 */ 76 DECLARE_BITMAP(states, (GPIO_INT7_HWIRQ - GPIO_INT0_HWIRQ + 1) * 3); 77 } sp_intc; 78 79 static struct irq_chip sp_intc_chip; 80 81 static void sp_intc_assign_bit(u32 hwirq, void __iomem *base, bool value) 82 { 83 u32 offset, mask; 84 unsigned long flags; 85 void __iomem *reg; 86 87 offset = (hwirq / 32) * 4; 88 reg = base + offset; 89 90 raw_spin_lock_irqsave(&sp_intc.lock, flags); 91 mask = readl_relaxed(reg); 92 if (value) 93 mask |= BIT(hwirq % 32); 94 else 95 mask &= ~BIT(hwirq % 32); 96 writel_relaxed(mask, reg); 97 raw_spin_unlock_irqrestore(&sp_intc.lock, flags); 98 } 99 100 static void sp_intc_ack_irq(struct irq_data *d) 101 { 102 u32 hwirq = d->hwirq; 103 104 if (unlikely(IS_GPIO_INT(hwirq) && TEST_STATE(hwirq, _IS_EDGE))) { // WORKAROUND 105 sp_intc_assign_bit(hwirq, REG_INTR_POLARITY, !TEST_STATE(hwirq, _IS_LOW)); 106 ASSIGN_STATE(hwirq, _IS_ACTIVE, true); 107 } 108 109 sp_intc_assign_bit(hwirq, REG_INTR_CLEAR, 1); 110 } 111 112 static void sp_intc_mask_irq(struct irq_data *d) 113 { 114 sp_intc_assign_bit(d->hwirq, REG_INTR_MASK, 0); 115 } 116 117 static void sp_intc_unmask_irq(struct irq_data *d) 118 { 119 sp_intc_assign_bit(d->hwirq, REG_INTR_MASK, 1); 120 } 121 122 static int sp_intc_set_type(struct irq_data *d, unsigned int type) 123 { 124 u32 hwirq = d->hwirq; 125 bool is_edge = !(type & IRQ_TYPE_LEVEL_MASK); 126 bool is_low = (type == IRQ_TYPE_LEVEL_LOW || type == IRQ_TYPE_EDGE_FALLING); 127 128 irq_set_handler_locked(d, is_edge ? handle_edge_irq : handle_level_irq); 129 130 if (unlikely(IS_GPIO_INT(hwirq) && is_edge)) { // WORKAROUND 131 /* store states */ 132 ASSIGN_STATE(hwirq, _IS_EDGE, is_edge); 133 ASSIGN_STATE(hwirq, _IS_LOW, is_low); 134 ASSIGN_STATE(hwirq, _IS_ACTIVE, false); 135 /* change to level */ 136 is_edge = false; 137 } 138 139 sp_intc_assign_bit(hwirq, REG_INTR_TYPE, is_edge); 140 sp_intc_assign_bit(hwirq, REG_INTR_POLARITY, is_low); 141 142 return 0; 143 } 144 145 static int sp_intc_get_ext_irq(int ext_num) 146 { 147 void __iomem *base = ext_num ? REG_MASKED_EXT1 : REG_MASKED_EXT0; 148 u32 shift = ext_num ? GROUP_SHIFT_EXT1 : GROUP_SHIFT_EXT0; 149 u32 groups; 150 u32 pending_group; 151 u32 group; 152 u32 pending_irq; 153 154 groups = readl_relaxed(REG_INTR_GROUP); 155 pending_group = (groups >> shift) & GROUP_MASK; 156 if (!pending_group) 157 return -1; 158 159 group = fls(pending_group) - 1; 160 pending_irq = readl_relaxed(base + group * 4); 161 if (!pending_irq) 162 return -1; 163 164 return (group * 32) + fls(pending_irq) - 1; 165 } 166 167 static void sp_intc_handle_ext_cascaded(struct irq_desc *desc) 168 { 169 struct irq_chip *chip = irq_desc_get_chip(desc); 170 int ext_num = (uintptr_t)irq_desc_get_handler_data(desc); 171 int hwirq; 172 173 chained_irq_enter(chip, desc); 174 175 while ((hwirq = sp_intc_get_ext_irq(ext_num)) >= 0) { 176 if (unlikely(IS_GPIO_INT(hwirq) && TEST_STATE(hwirq, _IS_ACTIVE))) { // WORKAROUND 177 ASSIGN_STATE(hwirq, _IS_ACTIVE, false); 178 sp_intc_assign_bit(hwirq, REG_INTR_POLARITY, TEST_STATE(hwirq, _IS_LOW)); 179 } else { 180 generic_handle_domain_irq(sp_intc.domain, hwirq); 181 } 182 } 183 184 chained_irq_exit(chip, desc); 185 } 186 187 static struct irq_chip sp_intc_chip = { 188 .name = "sp_intc", 189 .irq_ack = sp_intc_ack_irq, 190 .irq_mask = sp_intc_mask_irq, 191 .irq_unmask = sp_intc_unmask_irq, 192 .irq_set_type = sp_intc_set_type, 193 }; 194 195 static int sp_intc_irq_domain_map(struct irq_domain *domain, 196 unsigned int irq, irq_hw_number_t hwirq) 197 { 198 irq_set_chip_and_handler(irq, &sp_intc_chip, handle_level_irq); 199 irq_set_chip_data(irq, &sp_intc_chip); 200 irq_set_noprobe(irq); 201 202 return 0; 203 } 204 205 static const struct irq_domain_ops sp_intc_dm_ops = { 206 .xlate = irq_domain_xlate_twocell, 207 .map = sp_intc_irq_domain_map, 208 }; 209 210 static int sp_intc_irq_map(struct device_node *node, int i) 211 { 212 unsigned int irq; 213 214 irq = irq_of_parse_and_map(node, i); 215 if (!irq) 216 return -ENOENT; 217 218 irq_set_chained_handler_and_data(irq, sp_intc_handle_ext_cascaded, (void *)(uintptr_t)i); 219 220 return 0; 221 } 222 223 static int __init sp_intc_init_dt(struct device_node *node, struct device_node *parent) 224 { 225 int i, ret; 226 227 sp_intc.g0 = of_iomap(node, 0); 228 if (!sp_intc.g0) 229 return -ENXIO; 230 231 sp_intc.g1 = of_iomap(node, 1); 232 if (!sp_intc.g1) { 233 ret = -ENXIO; 234 goto out_unmap0; 235 } 236 237 ret = sp_intc_irq_map(node, 0); // EXT_INT0 238 if (ret) 239 goto out_unmap1; 240 241 ret = sp_intc_irq_map(node, 1); // EXT_INT1 242 if (ret) 243 goto out_unmap1; 244 245 /* initial regs */ 246 for (i = 0; i < SP_INTC_NR_GROUPS; i++) { 247 /* all mask */ 248 writel_relaxed(0, REG_INTR_MASK + i * 4); 249 /* all edge */ 250 writel_relaxed(~0, REG_INTR_TYPE + i * 4); 251 /* all high-active */ 252 writel_relaxed(0, REG_INTR_POLARITY + i * 4); 253 /* all EXT_INT0 */ 254 writel_relaxed(~0, REG_INTR_PRIORITY + i * 4); 255 /* all clear */ 256 writel_relaxed(~0, REG_INTR_CLEAR + i * 4); 257 } 258 259 sp_intc.domain = irq_domain_add_linear(node, SP_INTC_NR_IRQS, 260 &sp_intc_dm_ops, &sp_intc); 261 if (!sp_intc.domain) { 262 ret = -ENOMEM; 263 goto out_unmap1; 264 } 265 266 raw_spin_lock_init(&sp_intc.lock); 267 268 return 0; 269 270 out_unmap1: 271 iounmap(sp_intc.g1); 272 out_unmap0: 273 iounmap(sp_intc.g0); 274 275 return ret; 276 } 277 278 IRQCHIP_DECLARE(sp_intc, "sunplus,sp7021-intc", sp_intc_init_dt); 279