1 /* 2 * linux/arch/arm/common/vic.c 3 * 4 * Copyright (C) 1999 - 2003 ARM Limited 5 * Copyright (C) 2000 Deep Blue Solutions Ltd 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20 */ 21 22 #include <linux/export.h> 23 #include <linux/init.h> 24 #include <linux/list.h> 25 #include <linux/io.h> 26 #include <linux/irq.h> 27 #include <linux/irqchip.h> 28 #include <linux/irqchip/chained_irq.h> 29 #include <linux/irqdomain.h> 30 #include <linux/of.h> 31 #include <linux/of_address.h> 32 #include <linux/of_irq.h> 33 #include <linux/syscore_ops.h> 34 #include <linux/device.h> 35 #include <linux/amba/bus.h> 36 #include <linux/irqchip/arm-vic.h> 37 38 #include <asm/exception.h> 39 #include <asm/irq.h> 40 41 #define VIC_IRQ_STATUS 0x00 42 #define VIC_FIQ_STATUS 0x04 43 #define VIC_INT_SELECT 0x0c /* 1 = FIQ, 0 = IRQ */ 44 #define VIC_INT_SOFT 0x18 45 #define VIC_INT_SOFT_CLEAR 0x1c 46 #define VIC_PROTECT 0x20 47 #define VIC_PL190_VECT_ADDR 0x30 /* PL190 only */ 48 #define VIC_PL190_DEF_VECT_ADDR 0x34 /* PL190 only */ 49 50 #define VIC_VECT_ADDR0 0x100 /* 0 to 15 (0..31 PL192) */ 51 #define VIC_VECT_CNTL0 0x200 /* 0 to 15 (0..31 PL192) */ 52 #define VIC_ITCR 0x300 /* VIC test control register */ 53 54 #define VIC_VECT_CNTL_ENABLE (1 << 5) 55 56 #define VIC_PL192_VECT_ADDR 0xF00 57 58 /** 59 * struct vic_device - VIC PM device 60 * @parent_irq: The parent IRQ number of the VIC if cascaded, or 0. 61 * @irq: The IRQ number for the base of the VIC. 62 * @base: The register base for the VIC. 63 * @valid_sources: A bitmask of valid interrupts 64 * @resume_sources: A bitmask of interrupts for resume. 65 * @resume_irqs: The IRQs enabled for resume. 66 * @int_select: Save for VIC_INT_SELECT. 67 * @int_enable: Save for VIC_INT_ENABLE. 68 * @soft_int: Save for VIC_INT_SOFT. 69 * @protect: Save for VIC_PROTECT. 70 * @domain: The IRQ domain for the VIC. 71 */ 72 struct vic_device { 73 void __iomem *base; 74 int irq; 75 u32 valid_sources; 76 u32 resume_sources; 77 u32 resume_irqs; 78 u32 int_select; 79 u32 int_enable; 80 u32 soft_int; 81 u32 protect; 82 struct irq_domain *domain; 83 }; 84 85 /* we cannot allocate memory when VICs are initially registered */ 86 static struct vic_device vic_devices[CONFIG_ARM_VIC_NR]; 87 88 static int vic_id; 89 90 static void vic_handle_irq(struct pt_regs *regs); 91 92 /** 93 * vic_init2 - common initialisation code 94 * @base: Base of the VIC. 95 * 96 * Common initialisation code for registration 97 * and resume. 98 */ 99 static void vic_init2(void __iomem *base) 100 { 101 int i; 102 103 for (i = 0; i < 16; i++) { 104 void __iomem *reg = base + VIC_VECT_CNTL0 + (i * 4); 105 writel(VIC_VECT_CNTL_ENABLE | i, reg); 106 } 107 108 writel(32, base + VIC_PL190_DEF_VECT_ADDR); 109 } 110 111 #ifdef CONFIG_PM 112 static void resume_one_vic(struct vic_device *vic) 113 { 114 void __iomem *base = vic->base; 115 116 printk(KERN_DEBUG "%s: resuming vic at %p\n", __func__, base); 117 118 /* re-initialise static settings */ 119 vic_init2(base); 120 121 writel(vic->int_select, base + VIC_INT_SELECT); 122 writel(vic->protect, base + VIC_PROTECT); 123 124 /* set the enabled ints and then clear the non-enabled */ 125 writel(vic->int_enable, base + VIC_INT_ENABLE); 126 writel(~vic->int_enable, base + VIC_INT_ENABLE_CLEAR); 127 128 /* and the same for the soft-int register */ 129 130 writel(vic->soft_int, base + VIC_INT_SOFT); 131 writel(~vic->soft_int, base + VIC_INT_SOFT_CLEAR); 132 } 133 134 static void vic_resume(void) 135 { 136 int id; 137 138 for (id = vic_id - 1; id >= 0; id--) 139 resume_one_vic(vic_devices + id); 140 } 141 142 static void suspend_one_vic(struct vic_device *vic) 143 { 144 void __iomem *base = vic->base; 145 146 printk(KERN_DEBUG "%s: suspending vic at %p\n", __func__, base); 147 148 vic->int_select = readl(base + VIC_INT_SELECT); 149 vic->int_enable = readl(base + VIC_INT_ENABLE); 150 vic->soft_int = readl(base + VIC_INT_SOFT); 151 vic->protect = readl(base + VIC_PROTECT); 152 153 /* set the interrupts (if any) that are used for 154 * resuming the system */ 155 156 writel(vic->resume_irqs, base + VIC_INT_ENABLE); 157 writel(~vic->resume_irqs, base + VIC_INT_ENABLE_CLEAR); 158 } 159 160 static int vic_suspend(void) 161 { 162 int id; 163 164 for (id = 0; id < vic_id; id++) 165 suspend_one_vic(vic_devices + id); 166 167 return 0; 168 } 169 170 struct syscore_ops vic_syscore_ops = { 171 .suspend = vic_suspend, 172 .resume = vic_resume, 173 }; 174 175 /** 176 * vic_pm_init - initicall to register VIC pm 177 * 178 * This is called via late_initcall() to register 179 * the resources for the VICs due to the early 180 * nature of the VIC's registration. 181 */ 182 static int __init vic_pm_init(void) 183 { 184 if (vic_id > 0) 185 register_syscore_ops(&vic_syscore_ops); 186 187 return 0; 188 } 189 late_initcall(vic_pm_init); 190 #endif /* CONFIG_PM */ 191 192 static struct irq_chip vic_chip; 193 194 static int vic_irqdomain_map(struct irq_domain *d, unsigned int irq, 195 irq_hw_number_t hwirq) 196 { 197 struct vic_device *v = d->host_data; 198 199 /* Skip invalid IRQs, only register handlers for the real ones */ 200 if (!(v->valid_sources & (1 << hwirq))) 201 return -EPERM; 202 irq_set_chip_and_handler(irq, &vic_chip, handle_level_irq); 203 irq_set_chip_data(irq, v->base); 204 irq_set_probe(irq); 205 return 0; 206 } 207 208 /* 209 * Handle each interrupt in a single VIC. Returns non-zero if we've 210 * handled at least one interrupt. This reads the status register 211 * before handling each interrupt, which is necessary given that 212 * handle_IRQ may briefly re-enable interrupts for soft IRQ handling. 213 */ 214 static int handle_one_vic(struct vic_device *vic, struct pt_regs *regs) 215 { 216 u32 stat, irq; 217 int handled = 0; 218 219 while ((stat = readl_relaxed(vic->base + VIC_IRQ_STATUS))) { 220 irq = ffs(stat) - 1; 221 handle_domain_irq(vic->domain, irq, regs); 222 handled = 1; 223 } 224 225 return handled; 226 } 227 228 static void vic_handle_irq_cascaded(struct irq_desc *desc) 229 { 230 u32 stat, hwirq; 231 struct irq_chip *host_chip = irq_desc_get_chip(desc); 232 struct vic_device *vic = irq_desc_get_handler_data(desc); 233 234 chained_irq_enter(host_chip, desc); 235 236 while ((stat = readl_relaxed(vic->base + VIC_IRQ_STATUS))) { 237 hwirq = ffs(stat) - 1; 238 generic_handle_irq(irq_find_mapping(vic->domain, hwirq)); 239 } 240 241 chained_irq_exit(host_chip, desc); 242 } 243 244 /* 245 * Keep iterating over all registered VIC's until there are no pending 246 * interrupts. 247 */ 248 static void __exception_irq_entry vic_handle_irq(struct pt_regs *regs) 249 { 250 int i, handled; 251 252 do { 253 for (i = 0, handled = 0; i < vic_id; ++i) 254 handled |= handle_one_vic(&vic_devices[i], regs); 255 } while (handled); 256 } 257 258 static const struct irq_domain_ops vic_irqdomain_ops = { 259 .map = vic_irqdomain_map, 260 .xlate = irq_domain_xlate_onetwocell, 261 }; 262 263 /** 264 * vic_register() - Register a VIC. 265 * @base: The base address of the VIC. 266 * @parent_irq: The parent IRQ if cascaded, else 0. 267 * @irq: The base IRQ for the VIC. 268 * @valid_sources: bitmask of valid interrupts 269 * @resume_sources: bitmask of interrupts allowed for resume sources. 270 * @node: The device tree node associated with the VIC. 271 * 272 * Register the VIC with the system device tree so that it can be notified 273 * of suspend and resume requests and ensure that the correct actions are 274 * taken to re-instate the settings on resume. 275 * 276 * This also configures the IRQ domain for the VIC. 277 */ 278 static void __init vic_register(void __iomem *base, unsigned int parent_irq, 279 unsigned int irq, 280 u32 valid_sources, u32 resume_sources, 281 struct device_node *node) 282 { 283 struct vic_device *v; 284 int i; 285 286 if (vic_id >= ARRAY_SIZE(vic_devices)) { 287 printk(KERN_ERR "%s: too few VICs, increase CONFIG_ARM_VIC_NR\n", __func__); 288 return; 289 } 290 291 v = &vic_devices[vic_id]; 292 v->base = base; 293 v->valid_sources = valid_sources; 294 v->resume_sources = resume_sources; 295 set_handle_irq(vic_handle_irq); 296 vic_id++; 297 298 if (parent_irq) { 299 irq_set_chained_handler_and_data(parent_irq, 300 vic_handle_irq_cascaded, v); 301 } 302 303 v->domain = irq_domain_add_simple(node, fls(valid_sources), irq, 304 &vic_irqdomain_ops, v); 305 /* create an IRQ mapping for each valid IRQ */ 306 for (i = 0; i < fls(valid_sources); i++) 307 if (valid_sources & (1 << i)) 308 irq_create_mapping(v->domain, i); 309 /* If no base IRQ was passed, figure out our allocated base */ 310 if (irq) 311 v->irq = irq; 312 else 313 v->irq = irq_find_mapping(v->domain, 0); 314 } 315 316 static void vic_ack_irq(struct irq_data *d) 317 { 318 void __iomem *base = irq_data_get_irq_chip_data(d); 319 unsigned int irq = d->hwirq; 320 writel(1 << irq, base + VIC_INT_ENABLE_CLEAR); 321 /* moreover, clear the soft-triggered, in case it was the reason */ 322 writel(1 << irq, base + VIC_INT_SOFT_CLEAR); 323 } 324 325 static void vic_mask_irq(struct irq_data *d) 326 { 327 void __iomem *base = irq_data_get_irq_chip_data(d); 328 unsigned int irq = d->hwirq; 329 writel(1 << irq, base + VIC_INT_ENABLE_CLEAR); 330 } 331 332 static void vic_unmask_irq(struct irq_data *d) 333 { 334 void __iomem *base = irq_data_get_irq_chip_data(d); 335 unsigned int irq = d->hwirq; 336 writel(1 << irq, base + VIC_INT_ENABLE); 337 } 338 339 #if defined(CONFIG_PM) 340 static struct vic_device *vic_from_irq(unsigned int irq) 341 { 342 struct vic_device *v = vic_devices; 343 unsigned int base_irq = irq & ~31; 344 int id; 345 346 for (id = 0; id < vic_id; id++, v++) { 347 if (v->irq == base_irq) 348 return v; 349 } 350 351 return NULL; 352 } 353 354 static int vic_set_wake(struct irq_data *d, unsigned int on) 355 { 356 struct vic_device *v = vic_from_irq(d->irq); 357 unsigned int off = d->hwirq; 358 u32 bit = 1 << off; 359 360 if (!v) 361 return -EINVAL; 362 363 if (!(bit & v->resume_sources)) 364 return -EINVAL; 365 366 if (on) 367 v->resume_irqs |= bit; 368 else 369 v->resume_irqs &= ~bit; 370 371 return 0; 372 } 373 #else 374 #define vic_set_wake NULL 375 #endif /* CONFIG_PM */ 376 377 static struct irq_chip vic_chip = { 378 .name = "VIC", 379 .irq_ack = vic_ack_irq, 380 .irq_mask = vic_mask_irq, 381 .irq_unmask = vic_unmask_irq, 382 .irq_set_wake = vic_set_wake, 383 }; 384 385 static void __init vic_disable(void __iomem *base) 386 { 387 writel(0, base + VIC_INT_SELECT); 388 writel(0, base + VIC_INT_ENABLE); 389 writel(~0, base + VIC_INT_ENABLE_CLEAR); 390 writel(0, base + VIC_ITCR); 391 writel(~0, base + VIC_INT_SOFT_CLEAR); 392 } 393 394 static void __init vic_clear_interrupts(void __iomem *base) 395 { 396 unsigned int i; 397 398 writel(0, base + VIC_PL190_VECT_ADDR); 399 for (i = 0; i < 19; i++) { 400 unsigned int value; 401 402 value = readl(base + VIC_PL190_VECT_ADDR); 403 writel(value, base + VIC_PL190_VECT_ADDR); 404 } 405 } 406 407 /* 408 * The PL190 cell from ARM has been modified by ST to handle 64 interrupts. 409 * The original cell has 32 interrupts, while the modified one has 64, 410 * replocating two blocks 0x00..0x1f in 0x20..0x3f. In that case 411 * the probe function is called twice, with base set to offset 000 412 * and 020 within the page. We call this "second block". 413 */ 414 static void __init vic_init_st(void __iomem *base, unsigned int irq_start, 415 u32 vic_sources, struct device_node *node) 416 { 417 unsigned int i; 418 int vic_2nd_block = ((unsigned long)base & ~PAGE_MASK) != 0; 419 420 /* Disable all interrupts initially. */ 421 vic_disable(base); 422 423 /* 424 * Make sure we clear all existing interrupts. The vector registers 425 * in this cell are after the second block of general registers, 426 * so we can address them using standard offsets, but only from 427 * the second base address, which is 0x20 in the page 428 */ 429 if (vic_2nd_block) { 430 vic_clear_interrupts(base); 431 432 /* ST has 16 vectors as well, but we don't enable them by now */ 433 for (i = 0; i < 16; i++) { 434 void __iomem *reg = base + VIC_VECT_CNTL0 + (i * 4); 435 writel(0, reg); 436 } 437 438 writel(32, base + VIC_PL190_DEF_VECT_ADDR); 439 } 440 441 vic_register(base, 0, irq_start, vic_sources, 0, node); 442 } 443 444 void __init __vic_init(void __iomem *base, int parent_irq, int irq_start, 445 u32 vic_sources, u32 resume_sources, 446 struct device_node *node) 447 { 448 unsigned int i; 449 u32 cellid = 0; 450 enum amba_vendor vendor; 451 452 /* Identify which VIC cell this one is, by reading the ID */ 453 for (i = 0; i < 4; i++) { 454 void __iomem *addr; 455 addr = (void __iomem *)((u32)base & PAGE_MASK) + 0xfe0 + (i * 4); 456 cellid |= (readl(addr) & 0xff) << (8 * i); 457 } 458 vendor = (cellid >> 12) & 0xff; 459 printk(KERN_INFO "VIC @%p: id 0x%08x, vendor 0x%02x\n", 460 base, cellid, vendor); 461 462 switch(vendor) { 463 case AMBA_VENDOR_ST: 464 vic_init_st(base, irq_start, vic_sources, node); 465 return; 466 default: 467 printk(KERN_WARNING "VIC: unknown vendor, continuing anyways\n"); 468 /* fall through */ 469 case AMBA_VENDOR_ARM: 470 break; 471 } 472 473 /* Disable all interrupts initially. */ 474 vic_disable(base); 475 476 /* Make sure we clear all existing interrupts */ 477 vic_clear_interrupts(base); 478 479 vic_init2(base); 480 481 vic_register(base, parent_irq, irq_start, vic_sources, resume_sources, node); 482 } 483 484 /** 485 * vic_init() - initialise a vectored interrupt controller 486 * @base: iomem base address 487 * @irq_start: starting interrupt number, must be muliple of 32 488 * @vic_sources: bitmask of interrupt sources to allow 489 * @resume_sources: bitmask of interrupt sources to allow for resume 490 */ 491 void __init vic_init(void __iomem *base, unsigned int irq_start, 492 u32 vic_sources, u32 resume_sources) 493 { 494 __vic_init(base, 0, irq_start, vic_sources, resume_sources, NULL); 495 } 496 497 /** 498 * vic_init_cascaded() - initialise a cascaded vectored interrupt controller 499 * @base: iomem base address 500 * @parent_irq: the parent IRQ we're cascaded off 501 * @irq_start: starting interrupt number, must be muliple of 32 502 * @vic_sources: bitmask of interrupt sources to allow 503 * @resume_sources: bitmask of interrupt sources to allow for resume 504 * 505 * This returns the base for the new interrupts or negative on error. 506 */ 507 int __init vic_init_cascaded(void __iomem *base, unsigned int parent_irq, 508 u32 vic_sources, u32 resume_sources) 509 { 510 struct vic_device *v; 511 512 v = &vic_devices[vic_id]; 513 __vic_init(base, parent_irq, 0, vic_sources, resume_sources, NULL); 514 /* Return out acquired base */ 515 return v->irq; 516 } 517 EXPORT_SYMBOL_GPL(vic_init_cascaded); 518 519 #ifdef CONFIG_OF 520 int __init vic_of_init(struct device_node *node, struct device_node *parent) 521 { 522 void __iomem *regs; 523 u32 interrupt_mask = ~0; 524 u32 wakeup_mask = ~0; 525 526 if (WARN(parent, "non-root VICs are not supported")) 527 return -EINVAL; 528 529 regs = of_iomap(node, 0); 530 if (WARN_ON(!regs)) 531 return -EIO; 532 533 of_property_read_u32(node, "valid-mask", &interrupt_mask); 534 of_property_read_u32(node, "valid-wakeup-mask", &wakeup_mask); 535 536 /* 537 * Passing 0 as first IRQ makes the simple domain allocate descriptors 538 */ 539 __vic_init(regs, 0, 0, interrupt_mask, wakeup_mask, node); 540 541 return 0; 542 } 543 IRQCHIP_DECLARE(arm_pl190_vic, "arm,pl190-vic", vic_of_init); 544 IRQCHIP_DECLARE(arm_pl192_vic, "arm,pl192-vic", vic_of_init); 545 IRQCHIP_DECLARE(arm_versatile_vic, "arm,versatile-vic", vic_of_init); 546 #endif /* CONFIG OF */ 547