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 74struct bcm6345_l1_cpu; 75 76struct 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 84struct bcm6345_l1_cpu { 85 struct bcm6345_l1_chip *intc; 86 void __iomem *map_base; 87 unsigned int parent_irq; 88 u32 enable_cache[]; 89}; 90 91static inline unsigned int reg_enable(struct bcm6345_l1_chip *intc, 92 unsigned int word) 93{ 94#ifdef __BIG_ENDIAN 95 return (1 * intc->n_words - word - 1) * sizeof(u32); 96#else 97 return (0 * intc->n_words + word) * sizeof(u32); 98#endif 99} 100 101static inline unsigned int reg_status(struct bcm6345_l1_chip *intc, 102 unsigned int word) 103{ 104#ifdef __BIG_ENDIAN 105 return (2 * intc->n_words - word - 1) * sizeof(u32); 106#else 107 return (1 * intc->n_words + word) * sizeof(u32); 108#endif 109} 110 111static inline unsigned int cpu_for_irq(struct bcm6345_l1_chip *intc, 112 struct irq_data *d) 113{ 114 return cpumask_first_and(&intc->cpumask, irq_data_get_affinity_mask(d)); 115} 116 117static void bcm6345_l1_irq_handle(struct irq_desc *desc) 118{ 119 struct bcm6345_l1_cpu *cpu = irq_desc_get_handler_data(desc); 120 struct bcm6345_l1_chip *intc = cpu->intc; 121 struct irq_chip *chip = irq_desc_get_chip(desc); 122 unsigned int idx; 123 124 chained_irq_enter(chip, desc); 125 126 for (idx = 0; idx < intc->n_words; idx++) { 127 int base = idx * IRQS_PER_WORD; 128 unsigned long pending; 129 irq_hw_number_t hwirq; 130 unsigned int irq; 131 132 pending = __raw_readl(cpu->map_base + reg_status(intc, idx)); 133 pending &= __raw_readl(cpu->map_base + reg_enable(intc, idx)); 134 135 for_each_set_bit(hwirq, &pending, IRQS_PER_WORD) { 136 irq = irq_linear_revmap(intc->domain, base + hwirq); 137 if (irq) 138 generic_handle_irq(irq); 139 else 140 spurious_interrupt(); 141 } 142 } 143 144 chained_irq_exit(chip, desc); 145} 146 147static inline void __bcm6345_l1_unmask(struct irq_data *d) 148{ 149 struct bcm6345_l1_chip *intc = irq_data_get_irq_chip_data(d); 150 u32 word = d->hwirq / IRQS_PER_WORD; 151 u32 mask = BIT(d->hwirq % IRQS_PER_WORD); 152 unsigned int cpu_idx = cpu_for_irq(intc, d); 153 154 intc->cpus[cpu_idx]->enable_cache[word] |= mask; 155 __raw_writel(intc->cpus[cpu_idx]->enable_cache[word], 156 intc->cpus[cpu_idx]->map_base + reg_enable(intc, word)); 157} 158 159static inline void __bcm6345_l1_mask(struct irq_data *d) 160{ 161 struct bcm6345_l1_chip *intc = irq_data_get_irq_chip_data(d); 162 u32 word = d->hwirq / IRQS_PER_WORD; 163 u32 mask = BIT(d->hwirq % IRQS_PER_WORD); 164 unsigned int cpu_idx = cpu_for_irq(intc, d); 165 166 intc->cpus[cpu_idx]->enable_cache[word] &= ~mask; 167 __raw_writel(intc->cpus[cpu_idx]->enable_cache[word], 168 intc->cpus[cpu_idx]->map_base + reg_enable(intc, word)); 169} 170 171static void bcm6345_l1_unmask(struct irq_data *d) 172{ 173 struct bcm6345_l1_chip *intc = irq_data_get_irq_chip_data(d); 174 unsigned long flags; 175 176 raw_spin_lock_irqsave(&intc->lock, flags); 177 __bcm6345_l1_unmask(d); 178 raw_spin_unlock_irqrestore(&intc->lock, flags); 179} 180 181static void bcm6345_l1_mask(struct irq_data *d) 182{ 183 struct bcm6345_l1_chip *intc = irq_data_get_irq_chip_data(d); 184 unsigned long flags; 185 186 raw_spin_lock_irqsave(&intc->lock, flags); 187 __bcm6345_l1_mask(d); 188 raw_spin_unlock_irqrestore(&intc->lock, flags); 189} 190 191static int bcm6345_l1_set_affinity(struct irq_data *d, 192 const struct cpumask *dest, 193 bool force) 194{ 195 struct bcm6345_l1_chip *intc = irq_data_get_irq_chip_data(d); 196 u32 word = d->hwirq / IRQS_PER_WORD; 197 u32 mask = BIT(d->hwirq % IRQS_PER_WORD); 198 unsigned int old_cpu = cpu_for_irq(intc, d); 199 unsigned int new_cpu; 200 struct cpumask valid; 201 unsigned long flags; 202 bool enabled; 203 204 if (!cpumask_and(&valid, &intc->cpumask, dest)) 205 return -EINVAL; 206 207 new_cpu = cpumask_any_and(&valid, cpu_online_mask); 208 if (new_cpu >= nr_cpu_ids) 209 return -EINVAL; 210 211 dest = cpumask_of(new_cpu); 212 213 raw_spin_lock_irqsave(&intc->lock, flags); 214 if (old_cpu != new_cpu) { 215 enabled = intc->cpus[old_cpu]->enable_cache[word] & mask; 216 if (enabled) 217 __bcm6345_l1_mask(d); 218 cpumask_copy(irq_data_get_affinity_mask(d), dest); 219 if (enabled) 220 __bcm6345_l1_unmask(d); 221 } else { 222 cpumask_copy(irq_data_get_affinity_mask(d), dest); 223 } 224 raw_spin_unlock_irqrestore(&intc->lock, flags); 225 226 irq_data_update_effective_affinity(d, cpumask_of(new_cpu)); 227 228 return IRQ_SET_MASK_OK_NOCOPY; 229} 230 231static int __init bcm6345_l1_init_one(struct device_node *dn, 232 unsigned int idx, 233 struct bcm6345_l1_chip *intc) 234{ 235 struct resource res; 236 resource_size_t sz; 237 struct bcm6345_l1_cpu *cpu; 238 unsigned int i, n_words; 239 240 if (of_address_to_resource(dn, idx, &res)) 241 return -EINVAL; 242 sz = resource_size(&res); 243 n_words = sz / REG_BYTES_PER_IRQ_WORD; 244 245 if (!intc->n_words) 246 intc->n_words = n_words; 247 else if (intc->n_words != n_words) 248 return -EINVAL; 249 250 cpu = intc->cpus[idx] = kzalloc(sizeof(*cpu) + n_words * sizeof(u32), 251 GFP_KERNEL); 252 if (!cpu) 253 return -ENOMEM; 254 255 cpu->intc = intc; 256 cpu->map_base = ioremap(res.start, sz); 257 if (!cpu->map_base) 258 return -ENOMEM; 259 260 for (i = 0; i < n_words; i++) { 261 cpu->enable_cache[i] = 0; 262 __raw_writel(0, cpu->map_base + reg_enable(intc, i)); 263 } 264 265 cpu->parent_irq = irq_of_parse_and_map(dn, idx); 266 if (!cpu->parent_irq) { 267 pr_err("failed to map parent interrupt %d\n", cpu->parent_irq); 268 return -EINVAL; 269 } 270 irq_set_chained_handler_and_data(cpu->parent_irq, 271 bcm6345_l1_irq_handle, cpu); 272 273 return 0; 274} 275 276static struct irq_chip bcm6345_l1_irq_chip = { 277 .name = "bcm6345-l1", 278 .irq_mask = bcm6345_l1_mask, 279 .irq_unmask = bcm6345_l1_unmask, 280 .irq_set_affinity = bcm6345_l1_set_affinity, 281}; 282 283static int bcm6345_l1_map(struct irq_domain *d, unsigned int virq, 284 irq_hw_number_t hw_irq) 285{ 286 irq_set_chip_and_handler(virq, 287 &bcm6345_l1_irq_chip, handle_percpu_irq); 288 irq_set_chip_data(virq, d->host_data); 289 irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(virq))); 290 return 0; 291} 292 293static const struct irq_domain_ops bcm6345_l1_domain_ops = { 294 .xlate = irq_domain_xlate_onecell, 295 .map = bcm6345_l1_map, 296}; 297 298static int __init bcm6345_l1_of_init(struct device_node *dn, 299 struct device_node *parent) 300{ 301 struct bcm6345_l1_chip *intc; 302 unsigned int idx; 303 int ret; 304 305 intc = kzalloc(sizeof(*intc), GFP_KERNEL); 306 if (!intc) 307 return -ENOMEM; 308 309 for_each_possible_cpu(idx) { 310 ret = bcm6345_l1_init_one(dn, idx, intc); 311 if (ret) 312 pr_err("failed to init intc L1 for cpu %d: %d\n", 313 idx, ret); 314 else 315 cpumask_set_cpu(idx, &intc->cpumask); 316 } 317 318 if (!cpumask_weight(&intc->cpumask)) { 319 ret = -ENODEV; 320 goto out_free; 321 } 322 323 raw_spin_lock_init(&intc->lock); 324 325 intc->domain = irq_domain_add_linear(dn, IRQS_PER_WORD * intc->n_words, 326 &bcm6345_l1_domain_ops, 327 intc); 328 if (!intc->domain) { 329 ret = -ENOMEM; 330 goto out_unmap; 331 } 332 333 pr_info("registered BCM6345 L1 intc (IRQs: %d)\n", 334 IRQS_PER_WORD * intc->n_words); 335 for_each_cpu(idx, &intc->cpumask) { 336 struct bcm6345_l1_cpu *cpu = intc->cpus[idx]; 337 338 pr_info(" CPU%u at MMIO 0x%p (irq = %d)\n", idx, 339 cpu->map_base, cpu->parent_irq); 340 } 341 342 return 0; 343 344out_unmap: 345 for_each_possible_cpu(idx) { 346 struct bcm6345_l1_cpu *cpu = intc->cpus[idx]; 347 348 if (cpu) { 349 if (cpu->map_base) 350 iounmap(cpu->map_base); 351 kfree(cpu); 352 } 353 } 354out_free: 355 kfree(intc); 356 return ret; 357} 358 359IRQCHIP_DECLARE(bcm6345_l1, "brcm,bcm6345-l1-intc", bcm6345_l1_of_init); 360