1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2010-2011 Samsung Electronics Co., Ltd. 4 * http://www.samsung.com 5 * 6 * Combiner irqchip for EXYNOS 7 */ 8 #include <linux/err.h> 9 #include <linux/export.h> 10 #include <linux/init.h> 11 #include <linux/io.h> 12 #include <linux/slab.h> 13 #include <linux/syscore_ops.h> 14 #include <linux/irqdomain.h> 15 #include <linux/irqchip.h> 16 #include <linux/irqchip/chained_irq.h> 17 #include <linux/interrupt.h> 18 #include <linux/of_address.h> 19 #include <linux/of_irq.h> 20 21 #define COMBINER_ENABLE_SET 0x0 22 #define COMBINER_ENABLE_CLEAR 0x4 23 #define COMBINER_INT_STATUS 0xC 24 25 #define IRQ_IN_COMBINER 8 26 27 static DEFINE_SPINLOCK(irq_controller_lock); 28 29 struct combiner_chip_data { 30 unsigned int hwirq_offset; 31 unsigned int irq_mask; 32 void __iomem *base; 33 unsigned int parent_irq; 34 #ifdef CONFIG_PM 35 u32 pm_save; 36 #endif 37 }; 38 39 static struct combiner_chip_data *combiner_data; 40 static struct irq_domain *combiner_irq_domain; 41 static unsigned int max_nr = 20; 42 43 static inline void __iomem *combiner_base(struct irq_data *data) 44 { 45 struct combiner_chip_data *combiner_data = 46 irq_data_get_irq_chip_data(data); 47 48 return combiner_data->base; 49 } 50 51 static void combiner_mask_irq(struct irq_data *data) 52 { 53 u32 mask = 1 << (data->hwirq % 32); 54 55 writel_relaxed(mask, combiner_base(data) + COMBINER_ENABLE_CLEAR); 56 } 57 58 static void combiner_unmask_irq(struct irq_data *data) 59 { 60 u32 mask = 1 << (data->hwirq % 32); 61 62 writel_relaxed(mask, combiner_base(data) + COMBINER_ENABLE_SET); 63 } 64 65 static void combiner_handle_cascade_irq(struct irq_desc *desc) 66 { 67 struct combiner_chip_data *chip_data = irq_desc_get_handler_data(desc); 68 struct irq_chip *chip = irq_desc_get_chip(desc); 69 unsigned int combiner_irq; 70 unsigned long status; 71 int ret; 72 73 chained_irq_enter(chip, desc); 74 75 spin_lock(&irq_controller_lock); 76 status = readl_relaxed(chip_data->base + COMBINER_INT_STATUS); 77 spin_unlock(&irq_controller_lock); 78 status &= chip_data->irq_mask; 79 80 if (status == 0) 81 goto out; 82 83 combiner_irq = chip_data->hwirq_offset + __ffs(status); 84 ret = generic_handle_domain_irq(combiner_irq_domain, combiner_irq); 85 if (unlikely(ret)) 86 handle_bad_irq(desc); 87 88 out: 89 chained_irq_exit(chip, desc); 90 } 91 92 #ifdef CONFIG_SMP 93 static int combiner_set_affinity(struct irq_data *d, 94 const struct cpumask *mask_val, bool force) 95 { 96 struct combiner_chip_data *chip_data = irq_data_get_irq_chip_data(d); 97 struct irq_chip *chip = irq_get_chip(chip_data->parent_irq); 98 struct irq_data *data = irq_get_irq_data(chip_data->parent_irq); 99 100 if (chip && chip->irq_set_affinity) 101 return chip->irq_set_affinity(data, mask_val, force); 102 else 103 return -EINVAL; 104 } 105 #endif 106 107 static struct irq_chip combiner_chip = { 108 .name = "COMBINER", 109 .irq_mask = combiner_mask_irq, 110 .irq_unmask = combiner_unmask_irq, 111 #ifdef CONFIG_SMP 112 .irq_set_affinity = combiner_set_affinity, 113 #endif 114 }; 115 116 static void __init combiner_cascade_irq(struct combiner_chip_data *combiner_data, 117 unsigned int irq) 118 { 119 irq_set_chained_handler_and_data(irq, combiner_handle_cascade_irq, 120 combiner_data); 121 } 122 123 static void __init combiner_init_one(struct combiner_chip_data *combiner_data, 124 unsigned int combiner_nr, 125 void __iomem *base, unsigned int irq) 126 { 127 combiner_data->base = base; 128 combiner_data->hwirq_offset = (combiner_nr & ~3) * IRQ_IN_COMBINER; 129 combiner_data->irq_mask = 0xff << ((combiner_nr % 4) << 3); 130 combiner_data->parent_irq = irq; 131 132 /* Disable all interrupts */ 133 writel_relaxed(combiner_data->irq_mask, base + COMBINER_ENABLE_CLEAR); 134 } 135 136 static int combiner_irq_domain_xlate(struct irq_domain *d, 137 struct device_node *controller, 138 const u32 *intspec, unsigned int intsize, 139 unsigned long *out_hwirq, 140 unsigned int *out_type) 141 { 142 if (irq_domain_get_of_node(d) != controller) 143 return -EINVAL; 144 145 if (intsize < 2) 146 return -EINVAL; 147 148 *out_hwirq = intspec[0] * IRQ_IN_COMBINER + intspec[1]; 149 *out_type = 0; 150 151 return 0; 152 } 153 154 static int combiner_irq_domain_map(struct irq_domain *d, unsigned int irq, 155 irq_hw_number_t hw) 156 { 157 struct combiner_chip_data *combiner_data = d->host_data; 158 159 irq_set_chip_and_handler(irq, &combiner_chip, handle_level_irq); 160 irq_set_chip_data(irq, &combiner_data[hw >> 3]); 161 irq_set_probe(irq); 162 163 return 0; 164 } 165 166 static const struct irq_domain_ops combiner_irq_domain_ops = { 167 .xlate = combiner_irq_domain_xlate, 168 .map = combiner_irq_domain_map, 169 }; 170 171 static void __init combiner_init(void __iomem *combiner_base, 172 struct device_node *np) 173 { 174 int i, irq; 175 unsigned int nr_irq; 176 177 nr_irq = max_nr * IRQ_IN_COMBINER; 178 179 combiner_data = kcalloc(max_nr, sizeof (*combiner_data), GFP_KERNEL); 180 if (!combiner_data) 181 return; 182 183 combiner_irq_domain = irq_domain_add_linear(np, nr_irq, 184 &combiner_irq_domain_ops, combiner_data); 185 if (WARN_ON(!combiner_irq_domain)) { 186 pr_warn("%s: irq domain init failed\n", __func__); 187 return; 188 } 189 190 for (i = 0; i < max_nr; i++) { 191 irq = irq_of_parse_and_map(np, i); 192 193 combiner_init_one(&combiner_data[i], i, 194 combiner_base + (i >> 2) * 0x10, irq); 195 combiner_cascade_irq(&combiner_data[i], irq); 196 } 197 } 198 199 #ifdef CONFIG_PM 200 201 /** 202 * combiner_suspend - save interrupt combiner state before suspend 203 * 204 * Save the interrupt enable set register for all combiner groups since 205 * the state is lost when the system enters into a sleep state. 206 * 207 */ 208 static int combiner_suspend(void) 209 { 210 int i; 211 212 for (i = 0; i < max_nr; i++) 213 combiner_data[i].pm_save = 214 readl_relaxed(combiner_data[i].base + COMBINER_ENABLE_SET); 215 216 return 0; 217 } 218 219 /** 220 * combiner_resume - restore interrupt combiner state after resume 221 * 222 * Restore the interrupt enable set register for all combiner groups since 223 * the state is lost when the system enters into a sleep state on suspend. 224 * 225 */ 226 static void combiner_resume(void) 227 { 228 int i; 229 230 for (i = 0; i < max_nr; i++) { 231 writel_relaxed(combiner_data[i].irq_mask, 232 combiner_data[i].base + COMBINER_ENABLE_CLEAR); 233 writel_relaxed(combiner_data[i].pm_save, 234 combiner_data[i].base + COMBINER_ENABLE_SET); 235 } 236 } 237 238 #else 239 #define combiner_suspend NULL 240 #define combiner_resume NULL 241 #endif 242 243 static struct syscore_ops combiner_syscore_ops = { 244 .suspend = combiner_suspend, 245 .resume = combiner_resume, 246 }; 247 248 static int __init combiner_of_init(struct device_node *np, 249 struct device_node *parent) 250 { 251 void __iomem *combiner_base; 252 253 combiner_base = of_iomap(np, 0); 254 if (!combiner_base) { 255 pr_err("%s: failed to map combiner registers\n", __func__); 256 return -ENXIO; 257 } 258 259 if (of_property_read_u32(np, "samsung,combiner-nr", &max_nr)) { 260 pr_info("%s: number of combiners not specified, " 261 "setting default as %d.\n", 262 __func__, max_nr); 263 } 264 265 combiner_init(combiner_base, np); 266 267 register_syscore_ops(&combiner_syscore_ops); 268 269 return 0; 270 } 271 IRQCHIP_DECLARE(exynos4210_combiner, "samsung,exynos4210-combiner", 272 combiner_of_init); 273