1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * linux/arch/arm/common/vic.c 4 * 5 * Copyright (C) 1999 - 2003 ARM Limited 6 * Copyright (C) 2000 Deep Blue Solutions Ltd 7 */ 8 9 #include <linux/export.h> 10 #include <linux/init.h> 11 #include <linux/list.h> 12 #include <linux/io.h> 13 #include <linux/irq.h> 14 #include <linux/irqchip.h> 15 #include <linux/irqchip/chained_irq.h> 16 #include <linux/irqdomain.h> 17 #include <linux/of.h> 18 #include <linux/of_address.h> 19 #include <linux/of_irq.h> 20 #include <linux/syscore_ops.h> 21 #include <linux/device.h> 22 #include <linux/amba/bus.h> 23 #include <linux/irqchip/arm-vic.h> 24 25 #include <asm/exception.h> 26 #include <asm/irq.h> 27 28 #define VIC_IRQ_STATUS 0x00 29 #define VIC_FIQ_STATUS 0x04 30 #define VIC_INT_SELECT 0x0c /* 1 = FIQ, 0 = IRQ */ 31 #define VIC_INT_SOFT 0x18 32 #define VIC_INT_SOFT_CLEAR 0x1c 33 #define VIC_PROTECT 0x20 34 #define VIC_PL190_VECT_ADDR 0x30 /* PL190 only */ 35 #define VIC_PL190_DEF_VECT_ADDR 0x34 /* PL190 only */ 36 37 #define VIC_VECT_ADDR0 0x100 /* 0 to 15 (0..31 PL192) */ 38 #define VIC_VECT_CNTL0 0x200 /* 0 to 15 (0..31 PL192) */ 39 #define VIC_ITCR 0x300 /* VIC test control register */ 40 41 #define VIC_VECT_CNTL_ENABLE (1 << 5) 42 43 #define VIC_PL192_VECT_ADDR 0xF00 44 45 /** 46 * struct vic_device - VIC PM device 47 * @parent_irq: The parent IRQ number of the VIC if cascaded, or 0. 48 * @irq: The IRQ number for the base of the VIC. 49 * @base: The register base for the VIC. 50 * @valid_sources: A bitmask of valid interrupts 51 * @resume_sources: A bitmask of interrupts for resume. 52 * @resume_irqs: The IRQs enabled for resume. 53 * @int_select: Save for VIC_INT_SELECT. 54 * @int_enable: Save for VIC_INT_ENABLE. 55 * @soft_int: Save for VIC_INT_SOFT. 56 * @protect: Save for VIC_PROTECT. 57 * @domain: The IRQ domain for the VIC. 58 */ 59 struct vic_device { 60 void __iomem *base; 61 int irq; 62 u32 valid_sources; 63 u32 resume_sources; 64 u32 resume_irqs; 65 u32 int_select; 66 u32 int_enable; 67 u32 soft_int; 68 u32 protect; 69 struct irq_domain *domain; 70 }; 71 72 /* we cannot allocate memory when VICs are initially registered */ 73 static struct vic_device vic_devices[CONFIG_ARM_VIC_NR]; 74 75 static int vic_id; 76 77 static void vic_handle_irq(struct pt_regs *regs); 78 79 /** 80 * vic_init2 - common initialisation code 81 * @base: Base of the VIC. 82 * 83 * Common initialisation code for registration 84 * and resume. 85 */ 86 static void vic_init2(void __iomem *base) 87 { 88 int i; 89 90 for (i = 0; i < 16; i++) { 91 void __iomem *reg = base + VIC_VECT_CNTL0 + (i * 4); 92 writel(VIC_VECT_CNTL_ENABLE | i, reg); 93 } 94 95 writel(32, base + VIC_PL190_DEF_VECT_ADDR); 96 } 97 98 #ifdef CONFIG_PM 99 static void resume_one_vic(struct vic_device *vic) 100 { 101 void __iomem *base = vic->base; 102 103 printk(KERN_DEBUG "%s: resuming vic at %p\n", __func__, base); 104 105 /* re-initialise static settings */ 106 vic_init2(base); 107 108 writel(vic->int_select, base + VIC_INT_SELECT); 109 writel(vic->protect, base + VIC_PROTECT); 110 111 /* set the enabled ints and then clear the non-enabled */ 112 writel(vic->int_enable, base + VIC_INT_ENABLE); 113 writel(~vic->int_enable, base + VIC_INT_ENABLE_CLEAR); 114 115 /* and the same for the soft-int register */ 116 117 writel(vic->soft_int, base + VIC_INT_SOFT); 118 writel(~vic->soft_int, base + VIC_INT_SOFT_CLEAR); 119 } 120 121 static void vic_resume(void) 122 { 123 int id; 124 125 for (id = vic_id - 1; id >= 0; id--) 126 resume_one_vic(vic_devices + id); 127 } 128 129 static void suspend_one_vic(struct vic_device *vic) 130 { 131 void __iomem *base = vic->base; 132 133 printk(KERN_DEBUG "%s: suspending vic at %p\n", __func__, base); 134 135 vic->int_select = readl(base + VIC_INT_SELECT); 136 vic->int_enable = readl(base + VIC_INT_ENABLE); 137 vic->soft_int = readl(base + VIC_INT_SOFT); 138 vic->protect = readl(base + VIC_PROTECT); 139 140 /* set the interrupts (if any) that are used for 141 * resuming the system */ 142 143 writel(vic->resume_irqs, base + VIC_INT_ENABLE); 144 writel(~vic->resume_irqs, base + VIC_INT_ENABLE_CLEAR); 145 } 146 147 static int vic_suspend(void) 148 { 149 int id; 150 151 for (id = 0; id < vic_id; id++) 152 suspend_one_vic(vic_devices + id); 153 154 return 0; 155 } 156 157 static struct syscore_ops vic_syscore_ops = { 158 .suspend = vic_suspend, 159 .resume = vic_resume, 160 }; 161 162 /** 163 * vic_pm_init - initicall to register VIC pm 164 * 165 * This is called via late_initcall() to register 166 * the resources for the VICs due to the early 167 * nature of the VIC's registration. 168 */ 169 static int __init vic_pm_init(void) 170 { 171 if (vic_id > 0) 172 register_syscore_ops(&vic_syscore_ops); 173 174 return 0; 175 } 176 late_initcall(vic_pm_init); 177 #endif /* CONFIG_PM */ 178 179 static struct irq_chip vic_chip; 180 181 static int vic_irqdomain_map(struct irq_domain *d, unsigned int irq, 182 irq_hw_number_t hwirq) 183 { 184 struct vic_device *v = d->host_data; 185 186 /* Skip invalid IRQs, only register handlers for the real ones */ 187 if (!(v->valid_sources & (1 << hwirq))) 188 return -EPERM; 189 irq_set_chip_and_handler(irq, &vic_chip, handle_level_irq); 190 irq_set_chip_data(irq, v->base); 191 irq_set_probe(irq); 192 return 0; 193 } 194 195 /* 196 * Handle each interrupt in a single VIC. Returns non-zero if we've 197 * handled at least one interrupt. This reads the status register 198 * before handling each interrupt, which is necessary given that 199 * handle_IRQ may briefly re-enable interrupts for soft IRQ handling. 200 */ 201 static int handle_one_vic(struct vic_device *vic, struct pt_regs *regs) 202 { 203 u32 stat, irq; 204 int handled = 0; 205 206 while ((stat = readl_relaxed(vic->base + VIC_IRQ_STATUS))) { 207 irq = ffs(stat) - 1; 208 handle_domain_irq(vic->domain, irq, regs); 209 handled = 1; 210 } 211 212 return handled; 213 } 214 215 static void vic_handle_irq_cascaded(struct irq_desc *desc) 216 { 217 u32 stat, hwirq; 218 struct irq_chip *host_chip = irq_desc_get_chip(desc); 219 struct vic_device *vic = irq_desc_get_handler_data(desc); 220 221 chained_irq_enter(host_chip, desc); 222 223 while ((stat = readl_relaxed(vic->base + VIC_IRQ_STATUS))) { 224 hwirq = ffs(stat) - 1; 225 generic_handle_irq(irq_find_mapping(vic->domain, hwirq)); 226 } 227 228 chained_irq_exit(host_chip, desc); 229 } 230 231 /* 232 * Keep iterating over all registered VIC's until there are no pending 233 * interrupts. 234 */ 235 static void __exception_irq_entry vic_handle_irq(struct pt_regs *regs) 236 { 237 int i, handled; 238 239 do { 240 for (i = 0, handled = 0; i < vic_id; ++i) 241 handled |= handle_one_vic(&vic_devices[i], regs); 242 } while (handled); 243 } 244 245 static const struct irq_domain_ops vic_irqdomain_ops = { 246 .map = vic_irqdomain_map, 247 .xlate = irq_domain_xlate_onetwocell, 248 }; 249 250 /** 251 * vic_register() - Register a VIC. 252 * @base: The base address of the VIC. 253 * @parent_irq: The parent IRQ if cascaded, else 0. 254 * @irq: The base IRQ for the VIC. 255 * @valid_sources: bitmask of valid interrupts 256 * @resume_sources: bitmask of interrupts allowed for resume sources. 257 * @node: The device tree node associated with the VIC. 258 * 259 * Register the VIC with the system device tree so that it can be notified 260 * of suspend and resume requests and ensure that the correct actions are 261 * taken to re-instate the settings on resume. 262 * 263 * This also configures the IRQ domain for the VIC. 264 */ 265 static void __init vic_register(void __iomem *base, unsigned int parent_irq, 266 unsigned int irq, 267 u32 valid_sources, u32 resume_sources, 268 struct device_node *node) 269 { 270 struct vic_device *v; 271 int i; 272 273 if (vic_id >= ARRAY_SIZE(vic_devices)) { 274 printk(KERN_ERR "%s: too few VICs, increase CONFIG_ARM_VIC_NR\n", __func__); 275 return; 276 } 277 278 v = &vic_devices[vic_id]; 279 v->base = base; 280 v->valid_sources = valid_sources; 281 v->resume_sources = resume_sources; 282 set_handle_irq(vic_handle_irq); 283 vic_id++; 284 285 if (parent_irq) { 286 irq_set_chained_handler_and_data(parent_irq, 287 vic_handle_irq_cascaded, v); 288 } 289 290 v->domain = irq_domain_add_simple(node, fls(valid_sources), irq, 291 &vic_irqdomain_ops, v); 292 /* create an IRQ mapping for each valid IRQ */ 293 for (i = 0; i < fls(valid_sources); i++) 294 if (valid_sources & (1 << i)) 295 irq_create_mapping(v->domain, i); 296 /* If no base IRQ was passed, figure out our allocated base */ 297 if (irq) 298 v->irq = irq; 299 else 300 v->irq = irq_find_mapping(v->domain, 0); 301 } 302 303 static void vic_ack_irq(struct irq_data *d) 304 { 305 void __iomem *base = irq_data_get_irq_chip_data(d); 306 unsigned int irq = d->hwirq; 307 writel(1 << irq, base + VIC_INT_ENABLE_CLEAR); 308 /* moreover, clear the soft-triggered, in case it was the reason */ 309 writel(1 << irq, base + VIC_INT_SOFT_CLEAR); 310 } 311 312 static void vic_mask_irq(struct irq_data *d) 313 { 314 void __iomem *base = irq_data_get_irq_chip_data(d); 315 unsigned int irq = d->hwirq; 316 writel(1 << irq, base + VIC_INT_ENABLE_CLEAR); 317 } 318 319 static void vic_unmask_irq(struct irq_data *d) 320 { 321 void __iomem *base = irq_data_get_irq_chip_data(d); 322 unsigned int irq = d->hwirq; 323 writel(1 << irq, base + VIC_INT_ENABLE); 324 } 325 326 #if defined(CONFIG_PM) 327 static struct vic_device *vic_from_irq(unsigned int irq) 328 { 329 struct vic_device *v = vic_devices; 330 unsigned int base_irq = irq & ~31; 331 int id; 332 333 for (id = 0; id < vic_id; id++, v++) { 334 if (v->irq == base_irq) 335 return v; 336 } 337 338 return NULL; 339 } 340 341 static int vic_set_wake(struct irq_data *d, unsigned int on) 342 { 343 struct vic_device *v = vic_from_irq(d->irq); 344 unsigned int off = d->hwirq; 345 u32 bit = 1 << off; 346 347 if (!v) 348 return -EINVAL; 349 350 if (!(bit & v->resume_sources)) 351 return -EINVAL; 352 353 if (on) 354 v->resume_irqs |= bit; 355 else 356 v->resume_irqs &= ~bit; 357 358 return 0; 359 } 360 #else 361 #define vic_set_wake NULL 362 #endif /* CONFIG_PM */ 363 364 static struct irq_chip vic_chip = { 365 .name = "VIC", 366 .irq_ack = vic_ack_irq, 367 .irq_mask = vic_mask_irq, 368 .irq_unmask = vic_unmask_irq, 369 .irq_set_wake = vic_set_wake, 370 }; 371 372 static void __init vic_disable(void __iomem *base) 373 { 374 writel(0, base + VIC_INT_SELECT); 375 writel(0, base + VIC_INT_ENABLE); 376 writel(~0, base + VIC_INT_ENABLE_CLEAR); 377 writel(0, base + VIC_ITCR); 378 writel(~0, base + VIC_INT_SOFT_CLEAR); 379 } 380 381 static void __init vic_clear_interrupts(void __iomem *base) 382 { 383 unsigned int i; 384 385 writel(0, base + VIC_PL190_VECT_ADDR); 386 for (i = 0; i < 19; i++) { 387 unsigned int value; 388 389 value = readl(base + VIC_PL190_VECT_ADDR); 390 writel(value, base + VIC_PL190_VECT_ADDR); 391 } 392 } 393 394 /* 395 * The PL190 cell from ARM has been modified by ST to handle 64 interrupts. 396 * The original cell has 32 interrupts, while the modified one has 64, 397 * replocating two blocks 0x00..0x1f in 0x20..0x3f. In that case 398 * the probe function is called twice, with base set to offset 000 399 * and 020 within the page. We call this "second block". 400 */ 401 static void __init vic_init_st(void __iomem *base, unsigned int irq_start, 402 u32 vic_sources, struct device_node *node) 403 { 404 unsigned int i; 405 int vic_2nd_block = ((unsigned long)base & ~PAGE_MASK) != 0; 406 407 /* Disable all interrupts initially. */ 408 vic_disable(base); 409 410 /* 411 * Make sure we clear all existing interrupts. The vector registers 412 * in this cell are after the second block of general registers, 413 * so we can address them using standard offsets, but only from 414 * the second base address, which is 0x20 in the page 415 */ 416 if (vic_2nd_block) { 417 vic_clear_interrupts(base); 418 419 /* ST has 16 vectors as well, but we don't enable them by now */ 420 for (i = 0; i < 16; i++) { 421 void __iomem *reg = base + VIC_VECT_CNTL0 + (i * 4); 422 writel(0, reg); 423 } 424 425 writel(32, base + VIC_PL190_DEF_VECT_ADDR); 426 } 427 428 vic_register(base, 0, irq_start, vic_sources, 0, node); 429 } 430 431 void __init __vic_init(void __iomem *base, int parent_irq, int irq_start, 432 u32 vic_sources, u32 resume_sources, 433 struct device_node *node) 434 { 435 unsigned int i; 436 u32 cellid = 0; 437 enum amba_vendor vendor; 438 439 /* Identify which VIC cell this one is, by reading the ID */ 440 for (i = 0; i < 4; i++) { 441 void __iomem *addr; 442 addr = (void __iomem *)((u32)base & PAGE_MASK) + 0xfe0 + (i * 4); 443 cellid |= (readl(addr) & 0xff) << (8 * i); 444 } 445 vendor = (cellid >> 12) & 0xff; 446 printk(KERN_INFO "VIC @%p: id 0x%08x, vendor 0x%02x\n", 447 base, cellid, vendor); 448 449 switch(vendor) { 450 case AMBA_VENDOR_ST: 451 vic_init_st(base, irq_start, vic_sources, node); 452 return; 453 default: 454 printk(KERN_WARNING "VIC: unknown vendor, continuing anyways\n"); 455 /* fall through */ 456 case AMBA_VENDOR_ARM: 457 break; 458 } 459 460 /* Disable all interrupts initially. */ 461 vic_disable(base); 462 463 /* Make sure we clear all existing interrupts */ 464 vic_clear_interrupts(base); 465 466 vic_init2(base); 467 468 vic_register(base, parent_irq, irq_start, vic_sources, resume_sources, node); 469 } 470 471 /** 472 * vic_init() - initialise a vectored interrupt controller 473 * @base: iomem base address 474 * @irq_start: starting interrupt number, must be muliple of 32 475 * @vic_sources: bitmask of interrupt sources to allow 476 * @resume_sources: bitmask of interrupt sources to allow for resume 477 */ 478 void __init vic_init(void __iomem *base, unsigned int irq_start, 479 u32 vic_sources, u32 resume_sources) 480 { 481 __vic_init(base, 0, irq_start, vic_sources, resume_sources, NULL); 482 } 483 484 /** 485 * vic_init_cascaded() - initialise a cascaded vectored interrupt controller 486 * @base: iomem base address 487 * @parent_irq: the parent IRQ we're cascaded off 488 * @vic_sources: bitmask of interrupt sources to allow 489 * @resume_sources: bitmask of interrupt sources to allow for resume 490 * 491 * This returns the base for the new interrupts or negative on error. 492 */ 493 int __init vic_init_cascaded(void __iomem *base, unsigned int parent_irq, 494 u32 vic_sources, u32 resume_sources) 495 { 496 struct vic_device *v; 497 498 v = &vic_devices[vic_id]; 499 __vic_init(base, parent_irq, 0, vic_sources, resume_sources, NULL); 500 /* Return out acquired base */ 501 return v->irq; 502 } 503 EXPORT_SYMBOL_GPL(vic_init_cascaded); 504 505 #ifdef CONFIG_OF 506 static int __init vic_of_init(struct device_node *node, 507 struct device_node *parent) 508 { 509 void __iomem *regs; 510 u32 interrupt_mask = ~0; 511 u32 wakeup_mask = ~0; 512 513 if (WARN(parent, "non-root VICs are not supported")) 514 return -EINVAL; 515 516 regs = of_iomap(node, 0); 517 if (WARN_ON(!regs)) 518 return -EIO; 519 520 of_property_read_u32(node, "valid-mask", &interrupt_mask); 521 of_property_read_u32(node, "valid-wakeup-mask", &wakeup_mask); 522 523 /* 524 * Passing 0 as first IRQ makes the simple domain allocate descriptors 525 */ 526 __vic_init(regs, 0, 0, interrupt_mask, wakeup_mask, node); 527 528 return 0; 529 } 530 IRQCHIP_DECLARE(arm_pl190_vic, "arm,pl190-vic", vic_of_init); 531 IRQCHIP_DECLARE(arm_pl192_vic, "arm,pl192-vic", vic_of_init); 532 IRQCHIP_DECLARE(arm_versatile_vic, "arm,versatile-vic", vic_of_init); 533 #endif /* CONFIG OF */ 534