1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Broadcom BCM6345 style Level 1 interrupt controller driver 4 * 5 * Copyright (C) 2014 Broadcom Corporation 6 * Copyright 2015 Simon Arlott 7 * 8 * This is based on the BCM7038 (which supports SMP) but with a single 9 * enable register instead of separate mask/set/clear registers. 10 * 11 * The BCM3380 has a similar mask/status register layout, but each pair 12 * of words is at separate locations (and SMP is not supported). 13 * 14 * ENABLE/STATUS words are packed next to each other for each CPU: 15 * 16 * BCM6368: 17 * 0x1000_0020: CPU0_W0_ENABLE 18 * 0x1000_0024: CPU0_W1_ENABLE 19 * 0x1000_0028: CPU0_W0_STATUS IRQs 31-63 20 * 0x1000_002c: CPU0_W1_STATUS IRQs 0-31 21 * 0x1000_0030: CPU1_W0_ENABLE 22 * 0x1000_0034: CPU1_W1_ENABLE 23 * 0x1000_0038: CPU1_W0_STATUS IRQs 31-63 24 * 0x1000_003c: CPU1_W1_STATUS IRQs 0-31 25 * 26 * BCM63168: 27 * 0x1000_0020: CPU0_W0_ENABLE 28 * 0x1000_0024: CPU0_W1_ENABLE 29 * 0x1000_0028: CPU0_W2_ENABLE 30 * 0x1000_002c: CPU0_W3_ENABLE 31 * 0x1000_0030: CPU0_W0_STATUS IRQs 96-127 32 * 0x1000_0034: CPU0_W1_STATUS IRQs 64-95 33 * 0x1000_0038: CPU0_W2_STATUS IRQs 32-63 34 * 0x1000_003c: CPU0_W3_STATUS IRQs 0-31 35 * 0x1000_0040: CPU1_W0_ENABLE 36 * 0x1000_0044: CPU1_W1_ENABLE 37 * 0x1000_0048: CPU1_W2_ENABLE 38 * 0x1000_004c: CPU1_W3_ENABLE 39 * 0x1000_0050: CPU1_W0_STATUS IRQs 96-127 40 * 0x1000_0054: CPU1_W1_STATUS IRQs 64-95 41 * 0x1000_0058: CPU1_W2_STATUS IRQs 32-63 42 * 0x1000_005c: CPU1_W3_STATUS IRQs 0-31 43 * 44 * IRQs are numbered in CPU native endian order 45 * (which is big-endian in these examples) 46 */ 47 48 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 49 50 #include <linux/bitops.h> 51 #include <linux/cpumask.h> 52 #include <linux/kernel.h> 53 #include <linux/init.h> 54 #include <linux/interrupt.h> 55 #include <linux/io.h> 56 #include <linux/ioport.h> 57 #include <linux/irq.h> 58 #include <linux/irqdomain.h> 59 #include <linux/module.h> 60 #include <linux/of.h> 61 #include <linux/of_irq.h> 62 #include <linux/of_address.h> 63 #include <linux/of_platform.h> 64 #include <linux/platform_device.h> 65 #include <linux/slab.h> 66 #include <linux/smp.h> 67 #include <linux/types.h> 68 #include <linux/irqchip.h> 69 #include <linux/irqchip/chained_irq.h> 70 71 #define IRQS_PER_WORD 32 72 #define REG_BYTES_PER_IRQ_WORD (sizeof(u32) * 2) 73 74 struct bcm6345_l1_cpu; 75 76 struct bcm6345_l1_chip { 77 raw_spinlock_t lock; 78 unsigned int n_words; 79 struct irq_domain *domain; 80 struct cpumask cpumask; 81 struct bcm6345_l1_cpu *cpus[NR_CPUS]; 82 }; 83 84 struct bcm6345_l1_cpu { 85 void __iomem *map_base; 86 unsigned int parent_irq; 87 u32 enable_cache[]; 88 }; 89 90 static inline unsigned int reg_enable(struct bcm6345_l1_chip *intc, 91 unsigned int word) 92 { 93 #ifdef __BIG_ENDIAN 94 return (1 * intc->n_words - word - 1) * sizeof(u32); 95 #else 96 return (0 * intc->n_words + word) * sizeof(u32); 97 #endif 98 } 99 100 static inline unsigned int reg_status(struct bcm6345_l1_chip *intc, 101 unsigned int word) 102 { 103 #ifdef __BIG_ENDIAN 104 return (2 * intc->n_words - word - 1) * sizeof(u32); 105 #else 106 return (1 * intc->n_words + word) * sizeof(u32); 107 #endif 108 } 109 110 static inline unsigned int cpu_for_irq(struct bcm6345_l1_chip *intc, 111 struct irq_data *d) 112 { 113 return cpumask_first_and(&intc->cpumask, irq_data_get_affinity_mask(d)); 114 } 115 116 static void bcm6345_l1_irq_handle(struct irq_desc *desc) 117 { 118 struct bcm6345_l1_chip *intc = irq_desc_get_handler_data(desc); 119 struct bcm6345_l1_cpu *cpu; 120 struct irq_chip *chip = irq_desc_get_chip(desc); 121 unsigned int idx; 122 123 #ifdef CONFIG_SMP 124 cpu = intc->cpus[cpu_logical_map(smp_processor_id())]; 125 #else 126 cpu = intc->cpus[0]; 127 #endif 128 129 chained_irq_enter(chip, desc); 130 131 for (idx = 0; idx < intc->n_words; idx++) { 132 int base = idx * IRQS_PER_WORD; 133 unsigned long pending; 134 irq_hw_number_t hwirq; 135 136 pending = __raw_readl(cpu->map_base + reg_status(intc, idx)); 137 pending &= __raw_readl(cpu->map_base + reg_enable(intc, idx)); 138 139 for_each_set_bit(hwirq, &pending, IRQS_PER_WORD) { 140 if (generic_handle_domain_irq(intc->domain, base + hwirq)) 141 spurious_interrupt(); 142 } 143 } 144 145 chained_irq_exit(chip, desc); 146 } 147 148 static inline void __bcm6345_l1_unmask(struct irq_data *d) 149 { 150 struct bcm6345_l1_chip *intc = irq_data_get_irq_chip_data(d); 151 u32 word = d->hwirq / IRQS_PER_WORD; 152 u32 mask = BIT(d->hwirq % IRQS_PER_WORD); 153 unsigned int cpu_idx = cpu_for_irq(intc, d); 154 155 intc->cpus[cpu_idx]->enable_cache[word] |= mask; 156 __raw_writel(intc->cpus[cpu_idx]->enable_cache[word], 157 intc->cpus[cpu_idx]->map_base + reg_enable(intc, word)); 158 } 159 160 static inline void __bcm6345_l1_mask(struct irq_data *d) 161 { 162 struct bcm6345_l1_chip *intc = irq_data_get_irq_chip_data(d); 163 u32 word = d->hwirq / IRQS_PER_WORD; 164 u32 mask = BIT(d->hwirq % IRQS_PER_WORD); 165 unsigned int cpu_idx = cpu_for_irq(intc, d); 166 167 intc->cpus[cpu_idx]->enable_cache[word] &= ~mask; 168 __raw_writel(intc->cpus[cpu_idx]->enable_cache[word], 169 intc->cpus[cpu_idx]->map_base + reg_enable(intc, word)); 170 } 171 172 static void bcm6345_l1_unmask(struct irq_data *d) 173 { 174 struct bcm6345_l1_chip *intc = irq_data_get_irq_chip_data(d); 175 unsigned long flags; 176 177 raw_spin_lock_irqsave(&intc->lock, flags); 178 __bcm6345_l1_unmask(d); 179 raw_spin_unlock_irqrestore(&intc->lock, flags); 180 } 181 182 static void bcm6345_l1_mask(struct irq_data *d) 183 { 184 struct bcm6345_l1_chip *intc = irq_data_get_irq_chip_data(d); 185 unsigned long flags; 186 187 raw_spin_lock_irqsave(&intc->lock, flags); 188 __bcm6345_l1_mask(d); 189 raw_spin_unlock_irqrestore(&intc->lock, flags); 190 } 191 192 static int bcm6345_l1_set_affinity(struct irq_data *d, 193 const struct cpumask *dest, 194 bool force) 195 { 196 struct bcm6345_l1_chip *intc = irq_data_get_irq_chip_data(d); 197 u32 word = d->hwirq / IRQS_PER_WORD; 198 u32 mask = BIT(d->hwirq % IRQS_PER_WORD); 199 unsigned int old_cpu = cpu_for_irq(intc, d); 200 unsigned int new_cpu; 201 struct cpumask valid; 202 unsigned long flags; 203 bool enabled; 204 205 if (!cpumask_and(&valid, &intc->cpumask, dest)) 206 return -EINVAL; 207 208 new_cpu = cpumask_any_and(&valid, cpu_online_mask); 209 if (new_cpu >= nr_cpu_ids) 210 return -EINVAL; 211 212 dest = cpumask_of(new_cpu); 213 214 raw_spin_lock_irqsave(&intc->lock, flags); 215 if (old_cpu != new_cpu) { 216 enabled = intc->cpus[old_cpu]->enable_cache[word] & mask; 217 if (enabled) 218 __bcm6345_l1_mask(d); 219 irq_data_update_affinity(d, dest); 220 if (enabled) 221 __bcm6345_l1_unmask(d); 222 } else { 223 irq_data_update_affinity(d, dest); 224 } 225 raw_spin_unlock_irqrestore(&intc->lock, flags); 226 227 irq_data_update_effective_affinity(d, cpumask_of(new_cpu)); 228 229 return IRQ_SET_MASK_OK_NOCOPY; 230 } 231 232 static int __init bcm6345_l1_init_one(struct device_node *dn, 233 unsigned int idx, 234 struct bcm6345_l1_chip *intc) 235 { 236 struct resource res; 237 resource_size_t sz; 238 struct bcm6345_l1_cpu *cpu; 239 unsigned int i, n_words; 240 241 if (of_address_to_resource(dn, idx, &res)) 242 return -EINVAL; 243 sz = resource_size(&res); 244 n_words = sz / REG_BYTES_PER_IRQ_WORD; 245 246 if (!intc->n_words) 247 intc->n_words = n_words; 248 else if (intc->n_words != n_words) 249 return -EINVAL; 250 251 cpu = intc->cpus[idx] = kzalloc(sizeof(*cpu) + n_words * sizeof(u32), 252 GFP_KERNEL); 253 if (!cpu) 254 return -ENOMEM; 255 256 cpu->map_base = ioremap(res.start, sz); 257 if (!cpu->map_base) 258 return -ENOMEM; 259 260 if (!request_mem_region(res.start, sz, res.name)) 261 pr_err("failed to request intc memory"); 262 263 for (i = 0; i < n_words; i++) { 264 cpu->enable_cache[i] = 0; 265 __raw_writel(0, cpu->map_base + reg_enable(intc, i)); 266 } 267 268 cpu->parent_irq = irq_of_parse_and_map(dn, idx); 269 if (!cpu->parent_irq) { 270 pr_err("failed to map parent interrupt %d\n", cpu->parent_irq); 271 return -EINVAL; 272 } 273 irq_set_chained_handler_and_data(cpu->parent_irq, 274 bcm6345_l1_irq_handle, intc); 275 276 return 0; 277 } 278 279 static struct irq_chip bcm6345_l1_irq_chip = { 280 .name = "bcm6345-l1", 281 .irq_mask = bcm6345_l1_mask, 282 .irq_unmask = bcm6345_l1_unmask, 283 .irq_set_affinity = bcm6345_l1_set_affinity, 284 }; 285 286 static int bcm6345_l1_map(struct irq_domain *d, unsigned int virq, 287 irq_hw_number_t hw_irq) 288 { 289 irq_set_chip_and_handler(virq, 290 &bcm6345_l1_irq_chip, handle_percpu_irq); 291 irq_set_chip_data(virq, d->host_data); 292 irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(virq))); 293 return 0; 294 } 295 296 static const struct irq_domain_ops bcm6345_l1_domain_ops = { 297 .xlate = irq_domain_xlate_onecell, 298 .map = bcm6345_l1_map, 299 }; 300 301 static int __init bcm6345_l1_of_init(struct device_node *dn, 302 struct device_node *parent) 303 { 304 struct bcm6345_l1_chip *intc; 305 unsigned int idx; 306 int ret; 307 308 intc = kzalloc(sizeof(*intc), GFP_KERNEL); 309 if (!intc) 310 return -ENOMEM; 311 312 for_each_possible_cpu(idx) { 313 ret = bcm6345_l1_init_one(dn, idx, intc); 314 if (ret) 315 pr_err("failed to init intc L1 for cpu %d: %d\n", 316 idx, ret); 317 else 318 cpumask_set_cpu(idx, &intc->cpumask); 319 } 320 321 if (cpumask_empty(&intc->cpumask)) { 322 ret = -ENODEV; 323 goto out_free; 324 } 325 326 raw_spin_lock_init(&intc->lock); 327 328 intc->domain = irq_domain_add_linear(dn, IRQS_PER_WORD * intc->n_words, 329 &bcm6345_l1_domain_ops, 330 intc); 331 if (!intc->domain) { 332 ret = -ENOMEM; 333 goto out_unmap; 334 } 335 336 pr_info("registered BCM6345 L1 intc (IRQs: %d)\n", 337 IRQS_PER_WORD * intc->n_words); 338 for_each_cpu(idx, &intc->cpumask) { 339 struct bcm6345_l1_cpu *cpu = intc->cpus[idx]; 340 341 pr_info(" CPU%u (irq = %d)\n", idx, cpu->parent_irq); 342 } 343 344 return 0; 345 346 out_unmap: 347 for_each_possible_cpu(idx) { 348 struct bcm6345_l1_cpu *cpu = intc->cpus[idx]; 349 350 if (cpu) { 351 if (cpu->map_base) 352 iounmap(cpu->map_base); 353 kfree(cpu); 354 } 355 } 356 out_free: 357 kfree(intc); 358 return ret; 359 } 360 361 IRQCHIP_DECLARE(bcm6345_l1, "brcm,bcm6345-l1-intc", bcm6345_l1_of_init); 362