1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * 4 * Copyright (C) 2010 John Crispin <john@phrozen.org> 5 * Copyright (C) 2010 Thomas Langer <thomas.langer@lantiq.com> 6 */ 7 8 #include <linux/interrupt.h> 9 #include <linux/ioport.h> 10 #include <linux/sched.h> 11 #include <linux/irqchip.h> 12 #include <linux/irqdomain.h> 13 #include <linux/of_platform.h> 14 #include <linux/of_address.h> 15 #include <linux/of_irq.h> 16 17 #include <asm/bootinfo.h> 18 #include <asm/irq_cpu.h> 19 20 #include <lantiq_soc.h> 21 #include <irq.h> 22 23 /* register definitions - internal irqs */ 24 #define LTQ_ICU_ISR 0x0000 25 #define LTQ_ICU_IER 0x0008 26 #define LTQ_ICU_IOSR 0x0010 27 #define LTQ_ICU_IRSR 0x0018 28 #define LTQ_ICU_IMR 0x0020 29 30 #define LTQ_ICU_IM_SIZE 0x28 31 32 /* register definitions - external irqs */ 33 #define LTQ_EIU_EXIN_C 0x0000 34 #define LTQ_EIU_EXIN_INIC 0x0004 35 #define LTQ_EIU_EXIN_INC 0x0008 36 #define LTQ_EIU_EXIN_INEN 0x000C 37 38 /* number of external interrupts */ 39 #define MAX_EIU 6 40 41 /* the performance counter */ 42 #define LTQ_PERF_IRQ (INT_NUM_IM4_IRL0 + 31) 43 44 /* 45 * irqs generated by devices attached to the EBU need to be acked in 46 * a special manner 47 */ 48 #define LTQ_ICU_EBU_IRQ 22 49 50 #define ltq_icu_w32(vpe, m, x, y) \ 51 ltq_w32((x), ltq_icu_membase[vpe] + m*LTQ_ICU_IM_SIZE + (y)) 52 53 #define ltq_icu_r32(vpe, m, x) \ 54 ltq_r32(ltq_icu_membase[vpe] + m*LTQ_ICU_IM_SIZE + (x)) 55 56 #define ltq_eiu_w32(x, y) ltq_w32((x), ltq_eiu_membase + (y)) 57 #define ltq_eiu_r32(x) ltq_r32(ltq_eiu_membase + (x)) 58 59 /* we have a cascade of 8 irqs */ 60 #define MIPS_CPU_IRQ_CASCADE 8 61 62 static int exin_avail; 63 static u32 ltq_eiu_irq[MAX_EIU]; 64 static void __iomem *ltq_icu_membase[NR_CPUS]; 65 static void __iomem *ltq_eiu_membase; 66 static struct irq_domain *ltq_domain; 67 static DEFINE_SPINLOCK(ltq_eiu_lock); 68 static DEFINE_RAW_SPINLOCK(ltq_icu_lock); 69 static int ltq_perfcount_irq; 70 71 int ltq_eiu_get_irq(int exin) 72 { 73 if (exin < exin_avail) 74 return ltq_eiu_irq[exin]; 75 return -1; 76 } 77 78 void ltq_disable_irq(struct irq_data *d) 79 { 80 unsigned long offset = d->hwirq - MIPS_CPU_IRQ_CASCADE; 81 unsigned long im = offset / INT_NUM_IM_OFFSET; 82 unsigned long flags; 83 int vpe; 84 85 offset %= INT_NUM_IM_OFFSET; 86 87 raw_spin_lock_irqsave(<q_icu_lock, flags); 88 for_each_present_cpu(vpe) { 89 ltq_icu_w32(vpe, im, 90 ltq_icu_r32(vpe, im, LTQ_ICU_IER) & ~BIT(offset), 91 LTQ_ICU_IER); 92 } 93 raw_spin_unlock_irqrestore(<q_icu_lock, flags); 94 } 95 96 void ltq_mask_and_ack_irq(struct irq_data *d) 97 { 98 unsigned long offset = d->hwirq - MIPS_CPU_IRQ_CASCADE; 99 unsigned long im = offset / INT_NUM_IM_OFFSET; 100 unsigned long flags; 101 int vpe; 102 103 offset %= INT_NUM_IM_OFFSET; 104 105 raw_spin_lock_irqsave(<q_icu_lock, flags); 106 for_each_present_cpu(vpe) { 107 ltq_icu_w32(vpe, im, 108 ltq_icu_r32(vpe, im, LTQ_ICU_IER) & ~BIT(offset), 109 LTQ_ICU_IER); 110 ltq_icu_w32(vpe, im, BIT(offset), LTQ_ICU_ISR); 111 } 112 raw_spin_unlock_irqrestore(<q_icu_lock, flags); 113 } 114 115 static void ltq_ack_irq(struct irq_data *d) 116 { 117 unsigned long offset = d->hwirq - MIPS_CPU_IRQ_CASCADE; 118 unsigned long im = offset / INT_NUM_IM_OFFSET; 119 unsigned long flags; 120 int vpe; 121 122 offset %= INT_NUM_IM_OFFSET; 123 124 raw_spin_lock_irqsave(<q_icu_lock, flags); 125 for_each_present_cpu(vpe) { 126 ltq_icu_w32(vpe, im, BIT(offset), LTQ_ICU_ISR); 127 } 128 raw_spin_unlock_irqrestore(<q_icu_lock, flags); 129 } 130 131 void ltq_enable_irq(struct irq_data *d) 132 { 133 unsigned long offset = d->hwirq - MIPS_CPU_IRQ_CASCADE; 134 unsigned long im = offset / INT_NUM_IM_OFFSET; 135 unsigned long flags; 136 int vpe; 137 138 offset %= INT_NUM_IM_OFFSET; 139 140 vpe = cpumask_first(irq_data_get_effective_affinity_mask(d)); 141 142 /* This shouldn't be even possible, maybe during CPU hotplug spam */ 143 if (unlikely(vpe >= nr_cpu_ids)) 144 vpe = smp_processor_id(); 145 146 raw_spin_lock_irqsave(<q_icu_lock, flags); 147 148 ltq_icu_w32(vpe, im, ltq_icu_r32(vpe, im, LTQ_ICU_IER) | BIT(offset), 149 LTQ_ICU_IER); 150 151 raw_spin_unlock_irqrestore(<q_icu_lock, flags); 152 } 153 154 static int ltq_eiu_settype(struct irq_data *d, unsigned int type) 155 { 156 int i; 157 unsigned long flags; 158 159 for (i = 0; i < exin_avail; i++) { 160 if (d->hwirq == ltq_eiu_irq[i]) { 161 int val = 0; 162 int edge = 0; 163 164 switch (type) { 165 case IRQF_TRIGGER_NONE: 166 break; 167 case IRQF_TRIGGER_RISING: 168 val = 1; 169 edge = 1; 170 break; 171 case IRQF_TRIGGER_FALLING: 172 val = 2; 173 edge = 1; 174 break; 175 case IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING: 176 val = 3; 177 edge = 1; 178 break; 179 case IRQF_TRIGGER_HIGH: 180 val = 5; 181 break; 182 case IRQF_TRIGGER_LOW: 183 val = 6; 184 break; 185 default: 186 pr_err("invalid type %d for irq %ld\n", 187 type, d->hwirq); 188 return -EINVAL; 189 } 190 191 if (edge) 192 irq_set_handler(d->hwirq, handle_edge_irq); 193 194 spin_lock_irqsave(<q_eiu_lock, flags); 195 ltq_eiu_w32((ltq_eiu_r32(LTQ_EIU_EXIN_C) & 196 (~(7 << (i * 4)))) | (val << (i * 4)), 197 LTQ_EIU_EXIN_C); 198 spin_unlock_irqrestore(<q_eiu_lock, flags); 199 } 200 } 201 202 return 0; 203 } 204 205 static unsigned int ltq_startup_eiu_irq(struct irq_data *d) 206 { 207 int i; 208 209 ltq_enable_irq(d); 210 for (i = 0; i < exin_avail; i++) { 211 if (d->hwirq == ltq_eiu_irq[i]) { 212 /* by default we are low level triggered */ 213 ltq_eiu_settype(d, IRQF_TRIGGER_LOW); 214 /* clear all pending */ 215 ltq_eiu_w32(ltq_eiu_r32(LTQ_EIU_EXIN_INC) & ~BIT(i), 216 LTQ_EIU_EXIN_INC); 217 /* enable */ 218 ltq_eiu_w32(ltq_eiu_r32(LTQ_EIU_EXIN_INEN) | BIT(i), 219 LTQ_EIU_EXIN_INEN); 220 break; 221 } 222 } 223 224 return 0; 225 } 226 227 static void ltq_shutdown_eiu_irq(struct irq_data *d) 228 { 229 int i; 230 231 ltq_disable_irq(d); 232 for (i = 0; i < exin_avail; i++) { 233 if (d->hwirq == ltq_eiu_irq[i]) { 234 /* disable */ 235 ltq_eiu_w32(ltq_eiu_r32(LTQ_EIU_EXIN_INEN) & ~BIT(i), 236 LTQ_EIU_EXIN_INEN); 237 break; 238 } 239 } 240 } 241 242 #if defined(CONFIG_SMP) 243 static int ltq_icu_irq_set_affinity(struct irq_data *d, 244 const struct cpumask *cpumask, bool force) 245 { 246 struct cpumask tmask; 247 248 if (!cpumask_and(&tmask, cpumask, cpu_online_mask)) 249 return -EINVAL; 250 251 irq_data_update_effective_affinity(d, &tmask); 252 253 return IRQ_SET_MASK_OK; 254 } 255 #endif 256 257 static struct irq_chip ltq_irq_type = { 258 .name = "icu", 259 .irq_enable = ltq_enable_irq, 260 .irq_disable = ltq_disable_irq, 261 .irq_unmask = ltq_enable_irq, 262 .irq_ack = ltq_ack_irq, 263 .irq_mask = ltq_disable_irq, 264 .irq_mask_ack = ltq_mask_and_ack_irq, 265 #if defined(CONFIG_SMP) 266 .irq_set_affinity = ltq_icu_irq_set_affinity, 267 #endif 268 }; 269 270 static struct irq_chip ltq_eiu_type = { 271 .name = "eiu", 272 .irq_startup = ltq_startup_eiu_irq, 273 .irq_shutdown = ltq_shutdown_eiu_irq, 274 .irq_enable = ltq_enable_irq, 275 .irq_disable = ltq_disable_irq, 276 .irq_unmask = ltq_enable_irq, 277 .irq_ack = ltq_ack_irq, 278 .irq_mask = ltq_disable_irq, 279 .irq_mask_ack = ltq_mask_and_ack_irq, 280 .irq_set_type = ltq_eiu_settype, 281 #if defined(CONFIG_SMP) 282 .irq_set_affinity = ltq_icu_irq_set_affinity, 283 #endif 284 }; 285 286 static void ltq_hw_irq_handler(struct irq_desc *desc) 287 { 288 unsigned int module = irq_desc_get_irq(desc) - 2; 289 u32 irq; 290 irq_hw_number_t hwirq; 291 int vpe = smp_processor_id(); 292 293 irq = ltq_icu_r32(vpe, module, LTQ_ICU_IOSR); 294 if (irq == 0) 295 return; 296 297 /* 298 * silicon bug causes only the msb set to 1 to be valid. all 299 * other bits might be bogus 300 */ 301 irq = __fls(irq); 302 hwirq = irq + MIPS_CPU_IRQ_CASCADE + (INT_NUM_IM_OFFSET * module); 303 generic_handle_domain_irq(ltq_domain, hwirq); 304 305 /* if this is a EBU irq, we need to ack it or get a deadlock */ 306 if (irq == LTQ_ICU_EBU_IRQ && !module && LTQ_EBU_PCC_ISTAT != 0) 307 ltq_ebu_w32(ltq_ebu_r32(LTQ_EBU_PCC_ISTAT) | 0x10, 308 LTQ_EBU_PCC_ISTAT); 309 } 310 311 static int icu_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw) 312 { 313 struct irq_chip *chip = <q_irq_type; 314 struct irq_data *data; 315 int i; 316 317 if (hw < MIPS_CPU_IRQ_CASCADE) 318 return 0; 319 320 for (i = 0; i < exin_avail; i++) 321 if (hw == ltq_eiu_irq[i]) 322 chip = <q_eiu_type; 323 324 data = irq_get_irq_data(irq); 325 326 irq_data_update_effective_affinity(data, cpumask_of(0)); 327 328 irq_set_chip_and_handler(irq, chip, handle_level_irq); 329 330 return 0; 331 } 332 333 static const struct irq_domain_ops irq_domain_ops = { 334 .xlate = irq_domain_xlate_onetwocell, 335 .map = icu_map, 336 }; 337 338 int __init icu_of_init(struct device_node *node, struct device_node *parent) 339 { 340 struct device_node *eiu_node; 341 struct resource res; 342 int i, ret, vpe; 343 344 /* load register regions of available ICUs */ 345 for_each_possible_cpu(vpe) { 346 if (of_address_to_resource(node, vpe, &res)) 347 panic("Failed to get icu%i memory range", vpe); 348 349 if (!request_mem_region(res.start, resource_size(&res), 350 res.name)) 351 pr_err("Failed to request icu%i memory\n", vpe); 352 353 ltq_icu_membase[vpe] = ioremap(res.start, 354 resource_size(&res)); 355 356 if (!ltq_icu_membase[vpe]) 357 panic("Failed to remap icu%i memory", vpe); 358 } 359 360 /* turn off all irqs by default */ 361 for_each_possible_cpu(vpe) { 362 for (i = 0; i < MAX_IM; i++) { 363 /* make sure all irqs are turned off by default */ 364 ltq_icu_w32(vpe, i, 0, LTQ_ICU_IER); 365 366 /* clear all possibly pending interrupts */ 367 ltq_icu_w32(vpe, i, ~0, LTQ_ICU_ISR); 368 ltq_icu_w32(vpe, i, ~0, LTQ_ICU_IMR); 369 370 /* clear resend */ 371 ltq_icu_w32(vpe, i, 0, LTQ_ICU_IRSR); 372 } 373 } 374 375 mips_cpu_irq_init(); 376 377 for (i = 0; i < MAX_IM; i++) 378 irq_set_chained_handler(i + 2, ltq_hw_irq_handler); 379 380 ltq_domain = irq_domain_add_linear(node, 381 (MAX_IM * INT_NUM_IM_OFFSET) + MIPS_CPU_IRQ_CASCADE, 382 &irq_domain_ops, 0); 383 384 /* tell oprofile which irq to use */ 385 ltq_perfcount_irq = irq_create_mapping(ltq_domain, LTQ_PERF_IRQ); 386 387 /* the external interrupts are optional and xway only */ 388 eiu_node = of_find_compatible_node(NULL, NULL, "lantiq,eiu-xway"); 389 if (eiu_node && !of_address_to_resource(eiu_node, 0, &res)) { 390 /* find out how many external irq sources we have */ 391 exin_avail = of_property_count_u32_elems(eiu_node, 392 "lantiq,eiu-irqs"); 393 394 if (exin_avail > MAX_EIU) 395 exin_avail = MAX_EIU; 396 397 ret = of_property_read_u32_array(eiu_node, "lantiq,eiu-irqs", 398 ltq_eiu_irq, exin_avail); 399 if (ret) 400 panic("failed to load external irq resources"); 401 402 if (!request_mem_region(res.start, resource_size(&res), 403 res.name)) 404 pr_err("Failed to request eiu memory"); 405 406 ltq_eiu_membase = ioremap(res.start, 407 resource_size(&res)); 408 if (!ltq_eiu_membase) 409 panic("Failed to remap eiu memory"); 410 } 411 of_node_put(eiu_node); 412 413 return 0; 414 } 415 416 int get_c0_perfcount_int(void) 417 { 418 return ltq_perfcount_irq; 419 } 420 EXPORT_SYMBOL_GPL(get_c0_perfcount_int); 421 422 unsigned int get_c0_compare_int(void) 423 { 424 return CP0_LEGACY_COMPARE_IRQ; 425 } 426 427 IRQCHIP_DECLARE(lantiq_icu, "lantiq,icu", icu_of_init); 428 429 void __init arch_init_irq(void) 430 { 431 irqchip_init(); 432 } 433