1 /* 2 * Hisilicon HiP04 INTC 3 * 4 * Copyright (C) 2002-2014 ARM Limited. 5 * Copyright (c) 2013-2014 Hisilicon Ltd. 6 * Copyright (c) 2013-2014 Linaro Ltd. 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 * 12 * Interrupt architecture for the HIP04 INTC: 13 * 14 * o There is one Interrupt Distributor, which receives interrupts 15 * from system devices and sends them to the Interrupt Controllers. 16 * 17 * o There is one CPU Interface per CPU, which sends interrupts sent 18 * by the Distributor, and interrupts generated locally, to the 19 * associated CPU. The base address of the CPU interface is usually 20 * aliased so that the same address points to different chips depending 21 * on the CPU it is accessed from. 22 * 23 * Note that IRQs 0-31 are special - they are local to each CPU. 24 * As such, the enable set/clear, pending set/clear and active bit 25 * registers are banked per-cpu for these sources. 26 */ 27 28 #include <linux/init.h> 29 #include <linux/kernel.h> 30 #include <linux/err.h> 31 #include <linux/module.h> 32 #include <linux/list.h> 33 #include <linux/smp.h> 34 #include <linux/cpu.h> 35 #include <linux/cpu_pm.h> 36 #include <linux/cpumask.h> 37 #include <linux/io.h> 38 #include <linux/of.h> 39 #include <linux/of_address.h> 40 #include <linux/of_irq.h> 41 #include <linux/irqdomain.h> 42 #include <linux/interrupt.h> 43 #include <linux/slab.h> 44 #include <linux/irqchip.h> 45 #include <linux/irqchip/arm-gic.h> 46 47 #include <asm/irq.h> 48 #include <asm/exception.h> 49 #include <asm/smp_plat.h> 50 51 #include "irq-gic-common.h" 52 53 #define HIP04_MAX_IRQS 510 54 55 struct hip04_irq_data { 56 void __iomem *dist_base; 57 void __iomem *cpu_base; 58 struct irq_domain *domain; 59 unsigned int nr_irqs; 60 }; 61 62 static DEFINE_RAW_SPINLOCK(irq_controller_lock); 63 64 /* 65 * The GIC mapping of CPU interfaces does not necessarily match 66 * the logical CPU numbering. Let's use a mapping as returned 67 * by the GIC itself. 68 */ 69 #define NR_HIP04_CPU_IF 16 70 static u16 hip04_cpu_map[NR_HIP04_CPU_IF] __read_mostly; 71 72 static struct hip04_irq_data hip04_data __read_mostly; 73 74 static inline void __iomem *hip04_dist_base(struct irq_data *d) 75 { 76 struct hip04_irq_data *hip04_data = irq_data_get_irq_chip_data(d); 77 return hip04_data->dist_base; 78 } 79 80 static inline void __iomem *hip04_cpu_base(struct irq_data *d) 81 { 82 struct hip04_irq_data *hip04_data = irq_data_get_irq_chip_data(d); 83 return hip04_data->cpu_base; 84 } 85 86 static inline unsigned int hip04_irq(struct irq_data *d) 87 { 88 return d->hwirq; 89 } 90 91 /* 92 * Routines to acknowledge, disable and enable interrupts 93 */ 94 static void hip04_mask_irq(struct irq_data *d) 95 { 96 u32 mask = 1 << (hip04_irq(d) % 32); 97 98 raw_spin_lock(&irq_controller_lock); 99 writel_relaxed(mask, hip04_dist_base(d) + GIC_DIST_ENABLE_CLEAR + 100 (hip04_irq(d) / 32) * 4); 101 raw_spin_unlock(&irq_controller_lock); 102 } 103 104 static void hip04_unmask_irq(struct irq_data *d) 105 { 106 u32 mask = 1 << (hip04_irq(d) % 32); 107 108 raw_spin_lock(&irq_controller_lock); 109 writel_relaxed(mask, hip04_dist_base(d) + GIC_DIST_ENABLE_SET + 110 (hip04_irq(d) / 32) * 4); 111 raw_spin_unlock(&irq_controller_lock); 112 } 113 114 static void hip04_eoi_irq(struct irq_data *d) 115 { 116 writel_relaxed(hip04_irq(d), hip04_cpu_base(d) + GIC_CPU_EOI); 117 } 118 119 static int hip04_irq_set_type(struct irq_data *d, unsigned int type) 120 { 121 void __iomem *base = hip04_dist_base(d); 122 unsigned int irq = hip04_irq(d); 123 int ret; 124 125 /* Interrupt configuration for SGIs can't be changed */ 126 if (irq < 16) 127 return -EINVAL; 128 129 /* SPIs have restrictions on the supported types */ 130 if (irq >= 32 && type != IRQ_TYPE_LEVEL_HIGH && 131 type != IRQ_TYPE_EDGE_RISING) 132 return -EINVAL; 133 134 raw_spin_lock(&irq_controller_lock); 135 136 ret = gic_configure_irq(irq, type, base, NULL); 137 138 raw_spin_unlock(&irq_controller_lock); 139 140 return ret; 141 } 142 143 #ifdef CONFIG_SMP 144 static int hip04_irq_set_affinity(struct irq_data *d, 145 const struct cpumask *mask_val, 146 bool force) 147 { 148 void __iomem *reg; 149 unsigned int cpu, shift = (hip04_irq(d) % 2) * 16; 150 u32 val, mask, bit; 151 152 if (!force) 153 cpu = cpumask_any_and(mask_val, cpu_online_mask); 154 else 155 cpu = cpumask_first(mask_val); 156 157 if (cpu >= NR_HIP04_CPU_IF || cpu >= nr_cpu_ids) 158 return -EINVAL; 159 160 raw_spin_lock(&irq_controller_lock); 161 reg = hip04_dist_base(d) + GIC_DIST_TARGET + ((hip04_irq(d) * 2) & ~3); 162 mask = 0xffff << shift; 163 bit = hip04_cpu_map[cpu] << shift; 164 val = readl_relaxed(reg) & ~mask; 165 writel_relaxed(val | bit, reg); 166 raw_spin_unlock(&irq_controller_lock); 167 168 return IRQ_SET_MASK_OK; 169 } 170 #endif 171 172 static void __exception_irq_entry hip04_handle_irq(struct pt_regs *regs) 173 { 174 u32 irqstat, irqnr; 175 void __iomem *cpu_base = hip04_data.cpu_base; 176 177 do { 178 irqstat = readl_relaxed(cpu_base + GIC_CPU_INTACK); 179 irqnr = irqstat & GICC_IAR_INT_ID_MASK; 180 181 if (likely(irqnr > 15 && irqnr <= HIP04_MAX_IRQS)) { 182 handle_domain_irq(hip04_data.domain, irqnr, regs); 183 continue; 184 } 185 if (irqnr < 16) { 186 writel_relaxed(irqstat, cpu_base + GIC_CPU_EOI); 187 #ifdef CONFIG_SMP 188 handle_IPI(irqnr, regs); 189 #endif 190 continue; 191 } 192 break; 193 } while (1); 194 } 195 196 static struct irq_chip hip04_irq_chip = { 197 .name = "HIP04 INTC", 198 .irq_mask = hip04_mask_irq, 199 .irq_unmask = hip04_unmask_irq, 200 .irq_eoi = hip04_eoi_irq, 201 .irq_set_type = hip04_irq_set_type, 202 #ifdef CONFIG_SMP 203 .irq_set_affinity = hip04_irq_set_affinity, 204 #endif 205 .flags = IRQCHIP_SET_TYPE_MASKED | 206 IRQCHIP_SKIP_SET_WAKE | 207 IRQCHIP_MASK_ON_SUSPEND, 208 }; 209 210 static u16 hip04_get_cpumask(struct hip04_irq_data *intc) 211 { 212 void __iomem *base = intc->dist_base; 213 u32 mask, i; 214 215 for (i = mask = 0; i < 32; i += 2) { 216 mask = readl_relaxed(base + GIC_DIST_TARGET + i * 2); 217 mask |= mask >> 16; 218 if (mask) 219 break; 220 } 221 222 if (!mask) 223 pr_crit("GIC CPU mask not found - kernel will fail to boot.\n"); 224 225 return mask; 226 } 227 228 static void __init hip04_irq_dist_init(struct hip04_irq_data *intc) 229 { 230 unsigned int i; 231 u32 cpumask; 232 unsigned int nr_irqs = intc->nr_irqs; 233 void __iomem *base = intc->dist_base; 234 235 writel_relaxed(0, base + GIC_DIST_CTRL); 236 237 /* 238 * Set all global interrupts to this CPU only. 239 */ 240 cpumask = hip04_get_cpumask(intc); 241 cpumask |= cpumask << 16; 242 for (i = 32; i < nr_irqs; i += 2) 243 writel_relaxed(cpumask, base + GIC_DIST_TARGET + ((i * 2) & ~3)); 244 245 gic_dist_config(base, nr_irqs, NULL); 246 247 writel_relaxed(1, base + GIC_DIST_CTRL); 248 } 249 250 static void hip04_irq_cpu_init(struct hip04_irq_data *intc) 251 { 252 void __iomem *dist_base = intc->dist_base; 253 void __iomem *base = intc->cpu_base; 254 unsigned int cpu_mask, cpu = smp_processor_id(); 255 int i; 256 257 /* 258 * Get what the GIC says our CPU mask is. 259 */ 260 BUG_ON(cpu >= NR_HIP04_CPU_IF); 261 cpu_mask = hip04_get_cpumask(intc); 262 hip04_cpu_map[cpu] = cpu_mask; 263 264 /* 265 * Clear our mask from the other map entries in case they're 266 * still undefined. 267 */ 268 for (i = 0; i < NR_HIP04_CPU_IF; i++) 269 if (i != cpu) 270 hip04_cpu_map[i] &= ~cpu_mask; 271 272 gic_cpu_config(dist_base, NULL); 273 274 writel_relaxed(0xf0, base + GIC_CPU_PRIMASK); 275 writel_relaxed(1, base + GIC_CPU_CTRL); 276 } 277 278 #ifdef CONFIG_SMP 279 static void hip04_raise_softirq(const struct cpumask *mask, unsigned int irq) 280 { 281 int cpu; 282 unsigned long flags, map = 0; 283 284 raw_spin_lock_irqsave(&irq_controller_lock, flags); 285 286 /* Convert our logical CPU mask into a physical one. */ 287 for_each_cpu(cpu, mask) 288 map |= hip04_cpu_map[cpu]; 289 290 /* 291 * Ensure that stores to Normal memory are visible to the 292 * other CPUs before they observe us issuing the IPI. 293 */ 294 dmb(ishst); 295 296 /* this always happens on GIC0 */ 297 writel_relaxed(map << 8 | irq, hip04_data.dist_base + GIC_DIST_SOFTINT); 298 299 raw_spin_unlock_irqrestore(&irq_controller_lock, flags); 300 } 301 #endif 302 303 static int hip04_irq_domain_map(struct irq_domain *d, unsigned int irq, 304 irq_hw_number_t hw) 305 { 306 if (hw < 32) { 307 irq_set_percpu_devid(irq); 308 irq_set_chip_and_handler(irq, &hip04_irq_chip, 309 handle_percpu_devid_irq); 310 irq_set_status_flags(irq, IRQ_NOAUTOEN); 311 } else { 312 irq_set_chip_and_handler(irq, &hip04_irq_chip, 313 handle_fasteoi_irq); 314 irq_set_probe(irq); 315 } 316 irq_set_chip_data(irq, d->host_data); 317 return 0; 318 } 319 320 static int hip04_irq_domain_xlate(struct irq_domain *d, 321 struct device_node *controller, 322 const u32 *intspec, unsigned int intsize, 323 unsigned long *out_hwirq, 324 unsigned int *out_type) 325 { 326 unsigned long ret = 0; 327 328 if (irq_domain_get_of_node(d) != controller) 329 return -EINVAL; 330 if (intsize < 3) 331 return -EINVAL; 332 333 /* Get the interrupt number and add 16 to skip over SGIs */ 334 *out_hwirq = intspec[1] + 16; 335 336 /* For SPIs, we need to add 16 more to get the irq ID number */ 337 if (!intspec[0]) 338 *out_hwirq += 16; 339 340 *out_type = intspec[2] & IRQ_TYPE_SENSE_MASK; 341 342 return ret; 343 } 344 345 #ifdef CONFIG_SMP 346 static int hip04_irq_secondary_init(struct notifier_block *nfb, 347 unsigned long action, 348 void *hcpu) 349 { 350 if (action == CPU_STARTING || action == CPU_STARTING_FROZEN) 351 hip04_irq_cpu_init(&hip04_data); 352 return NOTIFY_OK; 353 } 354 355 /* 356 * Notifier for enabling the INTC CPU interface. Set an arbitrarily high 357 * priority because the GIC needs to be up before the ARM generic timers. 358 */ 359 static struct notifier_block hip04_irq_cpu_notifier = { 360 .notifier_call = hip04_irq_secondary_init, 361 .priority = 100, 362 }; 363 #endif 364 365 static const struct irq_domain_ops hip04_irq_domain_ops = { 366 .map = hip04_irq_domain_map, 367 .xlate = hip04_irq_domain_xlate, 368 }; 369 370 static int __init 371 hip04_of_init(struct device_node *node, struct device_node *parent) 372 { 373 irq_hw_number_t hwirq_base = 16; 374 int nr_irqs, irq_base, i; 375 376 if (WARN_ON(!node)) 377 return -ENODEV; 378 379 hip04_data.dist_base = of_iomap(node, 0); 380 WARN(!hip04_data.dist_base, "fail to map hip04 intc dist registers\n"); 381 382 hip04_data.cpu_base = of_iomap(node, 1); 383 WARN(!hip04_data.cpu_base, "unable to map hip04 intc cpu registers\n"); 384 385 /* 386 * Initialize the CPU interface map to all CPUs. 387 * It will be refined as each CPU probes its ID. 388 */ 389 for (i = 0; i < NR_HIP04_CPU_IF; i++) 390 hip04_cpu_map[i] = 0xffff; 391 392 /* 393 * Find out how many interrupts are supported. 394 * The HIP04 INTC only supports up to 510 interrupt sources. 395 */ 396 nr_irqs = readl_relaxed(hip04_data.dist_base + GIC_DIST_CTR) & 0x1f; 397 nr_irqs = (nr_irqs + 1) * 32; 398 if (nr_irqs > HIP04_MAX_IRQS) 399 nr_irqs = HIP04_MAX_IRQS; 400 hip04_data.nr_irqs = nr_irqs; 401 402 nr_irqs -= hwirq_base; /* calculate # of irqs to allocate */ 403 404 irq_base = irq_alloc_descs(-1, hwirq_base, nr_irqs, numa_node_id()); 405 if (irq_base < 0) { 406 pr_err("failed to allocate IRQ numbers\n"); 407 return -EINVAL; 408 } 409 410 hip04_data.domain = irq_domain_add_legacy(node, nr_irqs, irq_base, 411 hwirq_base, 412 &hip04_irq_domain_ops, 413 &hip04_data); 414 415 if (WARN_ON(!hip04_data.domain)) 416 return -EINVAL; 417 418 #ifdef CONFIG_SMP 419 set_smp_cross_call(hip04_raise_softirq); 420 register_cpu_notifier(&hip04_irq_cpu_notifier); 421 #endif 422 set_handle_irq(hip04_handle_irq); 423 424 hip04_irq_dist_init(&hip04_data); 425 hip04_irq_cpu_init(&hip04_data); 426 427 return 0; 428 } 429 IRQCHIP_DECLARE(hip04_intc, "hisilicon,hip04-intc", hip04_of_init); 430