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_RAW_STATUS 0x08 31 #define VIC_INT_SELECT 0x0c /* 1 = FIQ, 0 = IRQ */ 32 #define VIC_INT_ENABLE 0x10 /* 1 = enable, 0 = disable */ 33 #define VIC_INT_ENABLE_CLEAR 0x14 34 #define VIC_INT_SOFT 0x18 35 #define VIC_INT_SOFT_CLEAR 0x1c 36 #define VIC_PROTECT 0x20 37 #define VIC_PL190_VECT_ADDR 0x30 /* PL190 only */ 38 #define VIC_PL190_DEF_VECT_ADDR 0x34 /* PL190 only */ 39 40 #define VIC_VECT_ADDR0 0x100 /* 0 to 15 (0..31 PL192) */ 41 #define VIC_VECT_CNTL0 0x200 /* 0 to 15 (0..31 PL192) */ 42 #define VIC_ITCR 0x300 /* VIC test control register */ 43 44 #define VIC_VECT_CNTL_ENABLE (1 << 5) 45 46 #define VIC_PL192_VECT_ADDR 0xF00 47 48 /** 49 * struct vic_device - VIC PM device 50 * @base: The register base for the VIC. 51 * @irq: The IRQ number for the base of the VIC. 52 * @valid_sources: A bitmask of valid interrupts 53 * @resume_sources: A bitmask of interrupts for resume. 54 * @resume_irqs: The IRQs enabled for resume. 55 * @int_select: Save for VIC_INT_SELECT. 56 * @int_enable: Save for VIC_INT_ENABLE. 57 * @soft_int: Save for VIC_INT_SOFT. 58 * @protect: Save for VIC_PROTECT. 59 * @domain: The IRQ domain for the VIC. 60 */ 61 struct vic_device { 62 void __iomem *base; 63 int irq; 64 u32 valid_sources; 65 u32 resume_sources; 66 u32 resume_irqs; 67 u32 int_select; 68 u32 int_enable; 69 u32 soft_int; 70 u32 protect; 71 struct irq_domain *domain; 72 }; 73 74 /* we cannot allocate memory when VICs are initially registered */ 75 static struct vic_device vic_devices[CONFIG_ARM_VIC_NR]; 76 77 static int vic_id; 78 79 static void vic_handle_irq(struct pt_regs *regs); 80 81 /** 82 * vic_init2 - common initialisation code 83 * @base: Base of the VIC. 84 * 85 * Common initialisation code for registration 86 * and resume. 87 */ 88 static void vic_init2(void __iomem *base) 89 { 90 int i; 91 92 for (i = 0; i < 16; i++) { 93 void __iomem *reg = base + VIC_VECT_CNTL0 + (i * 4); 94 writel(VIC_VECT_CNTL_ENABLE | i, reg); 95 } 96 97 writel(32, base + VIC_PL190_DEF_VECT_ADDR); 98 } 99 100 #ifdef CONFIG_PM 101 static void resume_one_vic(struct vic_device *vic) 102 { 103 void __iomem *base = vic->base; 104 105 printk(KERN_DEBUG "%s: resuming vic at %p\n", __func__, base); 106 107 /* re-initialise static settings */ 108 vic_init2(base); 109 110 writel(vic->int_select, base + VIC_INT_SELECT); 111 writel(vic->protect, base + VIC_PROTECT); 112 113 /* set the enabled ints and then clear the non-enabled */ 114 writel(vic->int_enable, base + VIC_INT_ENABLE); 115 writel(~vic->int_enable, base + VIC_INT_ENABLE_CLEAR); 116 117 /* and the same for the soft-int register */ 118 119 writel(vic->soft_int, base + VIC_INT_SOFT); 120 writel(~vic->soft_int, base + VIC_INT_SOFT_CLEAR); 121 } 122 123 static void vic_resume(void) 124 { 125 int id; 126 127 for (id = vic_id - 1; id >= 0; id--) 128 resume_one_vic(vic_devices + id); 129 } 130 131 static void suspend_one_vic(struct vic_device *vic) 132 { 133 void __iomem *base = vic->base; 134 135 printk(KERN_DEBUG "%s: suspending vic at %p\n", __func__, base); 136 137 vic->int_select = readl(base + VIC_INT_SELECT); 138 vic->int_enable = readl(base + VIC_INT_ENABLE); 139 vic->soft_int = readl(base + VIC_INT_SOFT); 140 vic->protect = readl(base + VIC_PROTECT); 141 142 /* set the interrupts (if any) that are used for 143 * resuming the system */ 144 145 writel(vic->resume_irqs, base + VIC_INT_ENABLE); 146 writel(~vic->resume_irqs, base + VIC_INT_ENABLE_CLEAR); 147 } 148 149 static int vic_suspend(void) 150 { 151 int id; 152 153 for (id = 0; id < vic_id; id++) 154 suspend_one_vic(vic_devices + id); 155 156 return 0; 157 } 158 159 static struct syscore_ops vic_syscore_ops = { 160 .suspend = vic_suspend, 161 .resume = vic_resume, 162 }; 163 164 /** 165 * vic_pm_init - initcall to register VIC pm 166 * 167 * This is called via late_initcall() to register 168 * the resources for the VICs due to the early 169 * nature of the VIC's registration. 170 */ 171 static int __init vic_pm_init(void) 172 { 173 if (vic_id > 0) 174 register_syscore_ops(&vic_syscore_ops); 175 176 return 0; 177 } 178 late_initcall(vic_pm_init); 179 #endif /* CONFIG_PM */ 180 181 static struct irq_chip vic_chip; 182 183 static int vic_irqdomain_map(struct irq_domain *d, unsigned int irq, 184 irq_hw_number_t hwirq) 185 { 186 struct vic_device *v = d->host_data; 187 188 /* Skip invalid IRQs, only register handlers for the real ones */ 189 if (!(v->valid_sources & (1 << hwirq))) 190 return -EPERM; 191 irq_set_chip_and_handler(irq, &vic_chip, handle_level_irq); 192 irq_set_chip_data(irq, v->base); 193 irq_set_probe(irq); 194 return 0; 195 } 196 197 /* 198 * Handle each interrupt in a single VIC. Returns non-zero if we've 199 * handled at least one interrupt. This reads the status register 200 * before handling each interrupt, which is necessary given that 201 * handle_IRQ may briefly re-enable interrupts for soft IRQ handling. 202 */ 203 static int handle_one_vic(struct vic_device *vic, struct pt_regs *regs) 204 { 205 u32 stat, irq; 206 int handled = 0; 207 208 while ((stat = readl_relaxed(vic->base + VIC_IRQ_STATUS))) { 209 irq = ffs(stat) - 1; 210 generic_handle_domain_irq(vic->domain, irq); 211 handled = 1; 212 } 213 214 return handled; 215 } 216 217 static void vic_handle_irq_cascaded(struct irq_desc *desc) 218 { 219 u32 stat, hwirq; 220 struct irq_chip *host_chip = irq_desc_get_chip(desc); 221 struct vic_device *vic = irq_desc_get_handler_data(desc); 222 223 chained_irq_enter(host_chip, desc); 224 225 while ((stat = readl_relaxed(vic->base + VIC_IRQ_STATUS))) { 226 hwirq = ffs(stat) - 1; 227 generic_handle_domain_irq(vic->domain, hwirq); 228 } 229 230 chained_irq_exit(host_chip, desc); 231 } 232 233 /* 234 * Keep iterating over all registered VIC's until there are no pending 235 * interrupts. 236 */ 237 static void __exception_irq_entry vic_handle_irq(struct pt_regs *regs) 238 { 239 int i, handled; 240 241 do { 242 for (i = 0, handled = 0; i < vic_id; ++i) 243 handled |= handle_one_vic(&vic_devices[i], regs); 244 } while (handled); 245 } 246 247 static const struct irq_domain_ops vic_irqdomain_ops = { 248 .map = vic_irqdomain_map, 249 .xlate = irq_domain_xlate_onetwocell, 250 }; 251 252 /** 253 * vic_register() - Register a VIC. 254 * @base: The base address of the VIC. 255 * @parent_irq: The parent IRQ if cascaded, else 0. 256 * @irq: The base IRQ for the VIC. 257 * @valid_sources: bitmask of valid interrupts 258 * @resume_sources: bitmask of interrupts allowed for resume sources. 259 * @node: The device tree node associated with the VIC. 260 * 261 * Register the VIC with the system device tree so that it can be notified 262 * of suspend and resume requests and ensure that the correct actions are 263 * taken to re-instate the settings on resume. 264 * 265 * This also configures the IRQ domain for the VIC. 266 */ 267 static void __init vic_register(void __iomem *base, unsigned int parent_irq, 268 unsigned int irq, 269 u32 valid_sources, u32 resume_sources, 270 struct device_node *node) 271 { 272 struct vic_device *v; 273 int i; 274 275 if (vic_id >= ARRAY_SIZE(vic_devices)) { 276 printk(KERN_ERR "%s: too few VICs, increase CONFIG_ARM_VIC_NR\n", __func__); 277 return; 278 } 279 280 v = &vic_devices[vic_id]; 281 v->base = base; 282 v->valid_sources = valid_sources; 283 v->resume_sources = resume_sources; 284 set_handle_irq(vic_handle_irq); 285 vic_id++; 286 287 if (parent_irq) { 288 irq_set_chained_handler_and_data(parent_irq, 289 vic_handle_irq_cascaded, v); 290 } 291 292 v->domain = irq_domain_create_simple(of_fwnode_handle(node), 293 fls(valid_sources), irq, 294 &vic_irqdomain_ops, v); 295 /* create an IRQ mapping for each valid IRQ */ 296 for (i = 0; i < fls(valid_sources); i++) 297 if (valid_sources & (1 << i)) 298 irq_create_mapping(v->domain, i); 299 /* If no base IRQ was passed, figure out our allocated base */ 300 if (irq) 301 v->irq = irq; 302 else 303 v->irq = irq_find_mapping(v->domain, 0); 304 } 305 306 static void vic_ack_irq(struct irq_data *d) 307 { 308 void __iomem *base = irq_data_get_irq_chip_data(d); 309 unsigned int irq = d->hwirq; 310 writel(1 << irq, base + VIC_INT_ENABLE_CLEAR); 311 /* moreover, clear the soft-triggered, in case it was the reason */ 312 writel(1 << irq, base + VIC_INT_SOFT_CLEAR); 313 } 314 315 static void vic_mask_irq(struct irq_data *d) 316 { 317 void __iomem *base = irq_data_get_irq_chip_data(d); 318 unsigned int irq = d->hwirq; 319 writel(1 << irq, base + VIC_INT_ENABLE_CLEAR); 320 } 321 322 static void vic_unmask_irq(struct irq_data *d) 323 { 324 void __iomem *base = irq_data_get_irq_chip_data(d); 325 unsigned int irq = d->hwirq; 326 writel(1 << irq, base + VIC_INT_ENABLE); 327 } 328 329 #if defined(CONFIG_PM) 330 static struct vic_device *vic_from_irq(unsigned int irq) 331 { 332 struct vic_device *v = vic_devices; 333 unsigned int base_irq = irq & ~31; 334 int id; 335 336 for (id = 0; id < vic_id; id++, v++) { 337 if (v->irq == base_irq) 338 return v; 339 } 340 341 return NULL; 342 } 343 344 static int vic_set_wake(struct irq_data *d, unsigned int on) 345 { 346 struct vic_device *v = vic_from_irq(d->irq); 347 unsigned int off = d->hwirq; 348 u32 bit = 1 << off; 349 350 if (!v) 351 return -EINVAL; 352 353 if (!(bit & v->resume_sources)) 354 return -EINVAL; 355 356 if (on) 357 v->resume_irqs |= bit; 358 else 359 v->resume_irqs &= ~bit; 360 361 return 0; 362 } 363 #else 364 #define vic_set_wake NULL 365 #endif /* CONFIG_PM */ 366 367 static struct irq_chip vic_chip = { 368 .name = "VIC", 369 .irq_ack = vic_ack_irq, 370 .irq_mask = vic_mask_irq, 371 .irq_unmask = vic_unmask_irq, 372 .irq_set_wake = vic_set_wake, 373 }; 374 375 static void __init vic_disable(void __iomem *base) 376 { 377 writel(0, base + VIC_INT_SELECT); 378 writel(0, base + VIC_INT_ENABLE); 379 writel(~0, base + VIC_INT_ENABLE_CLEAR); 380 writel(0, base + VIC_ITCR); 381 writel(~0, base + VIC_INT_SOFT_CLEAR); 382 } 383 384 static void __init vic_clear_interrupts(void __iomem *base) 385 { 386 unsigned int i; 387 388 writel(0, base + VIC_PL190_VECT_ADDR); 389 for (i = 0; i < 19; i++) { 390 unsigned int value; 391 392 value = readl(base + VIC_PL190_VECT_ADDR); 393 writel(value, base + VIC_PL190_VECT_ADDR); 394 } 395 } 396 397 /* 398 * The PL190 cell from ARM has been modified by ST to handle 64 interrupts. 399 * The original cell has 32 interrupts, while the modified one has 64, 400 * replicating two blocks 0x00..0x1f in 0x20..0x3f. In that case 401 * the probe function is called twice, with base set to offset 000 402 * and 020 within the page. We call this "second block". 403 */ 404 static void __init vic_init_st(void __iomem *base, unsigned int irq_start, 405 u32 vic_sources, struct device_node *node) 406 { 407 unsigned int i; 408 int vic_2nd_block = ((unsigned long)base & ~PAGE_MASK) != 0; 409 410 /* Disable all interrupts initially. */ 411 vic_disable(base); 412 413 /* 414 * Make sure we clear all existing interrupts. The vector registers 415 * in this cell are after the second block of general registers, 416 * so we can address them using standard offsets, but only from 417 * the second base address, which is 0x20 in the page 418 */ 419 if (vic_2nd_block) { 420 vic_clear_interrupts(base); 421 422 /* ST has 16 vectors as well, but we don't enable them by now */ 423 for (i = 0; i < 16; i++) { 424 void __iomem *reg = base + VIC_VECT_CNTL0 + (i * 4); 425 writel(0, reg); 426 } 427 428 writel(32, base + VIC_PL190_DEF_VECT_ADDR); 429 } 430 431 vic_register(base, 0, irq_start, vic_sources, 0, node); 432 } 433 434 static void __init __vic_init(void __iomem *base, int parent_irq, int irq_start, 435 u32 vic_sources, u32 resume_sources, 436 struct device_node *node) 437 { 438 unsigned int i; 439 u32 cellid = 0; 440 enum amba_vendor vendor; 441 442 /* Identify which VIC cell this one is, by reading the ID */ 443 for (i = 0; i < 4; i++) { 444 void __iomem *addr; 445 addr = (void __iomem *)((u32)base & PAGE_MASK) + 0xfe0 + (i * 4); 446 cellid |= (readl(addr) & 0xff) << (8 * i); 447 } 448 vendor = (cellid >> 12) & 0xff; 449 printk(KERN_INFO "VIC @%p: id 0x%08x, vendor 0x%02x\n", 450 base, cellid, vendor); 451 452 switch(vendor) { 453 case AMBA_VENDOR_ST: 454 vic_init_st(base, irq_start, vic_sources, node); 455 return; 456 default: 457 printk(KERN_WARNING "VIC: unknown vendor, continuing anyways\n"); 458 fallthrough; 459 case AMBA_VENDOR_ARM: 460 break; 461 } 462 463 /* Disable all interrupts initially. */ 464 vic_disable(base); 465 466 /* Make sure we clear all existing interrupts */ 467 vic_clear_interrupts(base); 468 469 vic_init2(base); 470 471 vic_register(base, parent_irq, irq_start, vic_sources, resume_sources, node); 472 } 473 474 /** 475 * vic_init() - initialise a vectored interrupt controller 476 * @base: iomem base address 477 * @irq_start: starting interrupt number, must be muliple of 32 478 * @vic_sources: bitmask of interrupt sources to allow 479 * @resume_sources: bitmask of interrupt sources to allow for resume 480 */ 481 void __init vic_init(void __iomem *base, unsigned int irq_start, 482 u32 vic_sources, u32 resume_sources) 483 { 484 __vic_init(base, 0, irq_start, vic_sources, resume_sources, NULL); 485 } 486 487 #ifdef CONFIG_OF 488 static int __init vic_of_init(struct device_node *node, 489 struct device_node *parent) 490 { 491 void __iomem *regs; 492 u32 interrupt_mask = ~0; 493 u32 wakeup_mask = ~0; 494 int parent_irq; 495 496 regs = of_iomap(node, 0); 497 if (WARN_ON(!regs)) 498 return -EIO; 499 500 of_property_read_u32(node, "valid-mask", &interrupt_mask); 501 of_property_read_u32(node, "valid-wakeup-mask", &wakeup_mask); 502 parent_irq = of_irq_get(node, 0); 503 if (parent_irq < 0) 504 parent_irq = 0; 505 506 /* 507 * Passing 0 as first IRQ makes the simple domain allocate descriptors 508 */ 509 __vic_init(regs, parent_irq, 0, interrupt_mask, wakeup_mask, node); 510 511 return 0; 512 } 513 IRQCHIP_DECLARE(arm_pl190_vic, "arm,pl190-vic", vic_of_init); 514 IRQCHIP_DECLARE(arm_pl192_vic, "arm,pl192-vic", vic_of_init); 515 IRQCHIP_DECLARE(arm_versatile_vic, "arm,versatile-vic", vic_of_init); 516 #endif /* CONFIG OF */ 517