1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Renesas INTC External IRQ Pin Driver 4 * 5 * Copyright (C) 2013 Magnus Damm 6 */ 7 8 #include <linux/init.h> 9 #include <linux/of.h> 10 #include <linux/platform_device.h> 11 #include <linux/spinlock.h> 12 #include <linux/interrupt.h> 13 #include <linux/ioport.h> 14 #include <linux/io.h> 15 #include <linux/irq.h> 16 #include <linux/irqdomain.h> 17 #include <linux/err.h> 18 #include <linux/slab.h> 19 #include <linux/module.h> 20 #include <linux/pm_runtime.h> 21 22 #define INTC_IRQPIN_MAX 8 /* maximum 8 interrupts per driver instance */ 23 24 #define INTC_IRQPIN_REG_SENSE 0 /* ICRn */ 25 #define INTC_IRQPIN_REG_PRIO 1 /* INTPRInn */ 26 #define INTC_IRQPIN_REG_SOURCE 2 /* INTREQnn */ 27 #define INTC_IRQPIN_REG_MASK 3 /* INTMSKnn */ 28 #define INTC_IRQPIN_REG_CLEAR 4 /* INTMSKCLRnn */ 29 #define INTC_IRQPIN_REG_NR_MANDATORY 5 30 #define INTC_IRQPIN_REG_IRLM 5 /* ICR0 with IRLM bit (optional) */ 31 #define INTC_IRQPIN_REG_NR 6 32 33 /* INTC external IRQ PIN hardware register access: 34 * 35 * SENSE is read-write 32-bit with 2-bits or 4-bits per IRQ (*) 36 * PRIO is read-write 32-bit with 4-bits per IRQ (**) 37 * SOURCE is read-only 32-bit or 8-bit with 1-bit per IRQ (***) 38 * MASK is write-only 32-bit or 8-bit with 1-bit per IRQ (***) 39 * CLEAR is write-only 32-bit or 8-bit with 1-bit per IRQ (***) 40 * 41 * (*) May be accessed by more than one driver instance - lock needed 42 * (**) Read-modify-write access by one driver instance - lock needed 43 * (***) Accessed by one driver instance only - no locking needed 44 */ 45 46 struct intc_irqpin_iomem { 47 void __iomem *iomem; 48 unsigned long (*read)(void __iomem *iomem); 49 void (*write)(void __iomem *iomem, unsigned long data); 50 int width; 51 }; 52 53 struct intc_irqpin_irq { 54 int hw_irq; 55 int requested_irq; 56 int domain_irq; 57 struct intc_irqpin_priv *p; 58 }; 59 60 struct intc_irqpin_priv { 61 struct intc_irqpin_iomem iomem[INTC_IRQPIN_REG_NR]; 62 struct intc_irqpin_irq irq[INTC_IRQPIN_MAX]; 63 unsigned int sense_bitfield_width; 64 struct platform_device *pdev; 65 struct irq_chip irq_chip; 66 struct irq_domain *irq_domain; 67 atomic_t wakeup_path; 68 unsigned shared_irqs:1; 69 u8 shared_irq_mask; 70 }; 71 72 struct intc_irqpin_config { 73 int irlm_bit; /* -1 if non-existent */ 74 }; 75 76 static unsigned long intc_irqpin_read32(void __iomem *iomem) 77 { 78 return ioread32(iomem); 79 } 80 81 static unsigned long intc_irqpin_read8(void __iomem *iomem) 82 { 83 return ioread8(iomem); 84 } 85 86 static void intc_irqpin_write32(void __iomem *iomem, unsigned long data) 87 { 88 iowrite32(data, iomem); 89 } 90 91 static void intc_irqpin_write8(void __iomem *iomem, unsigned long data) 92 { 93 iowrite8(data, iomem); 94 } 95 96 static inline unsigned long intc_irqpin_read(struct intc_irqpin_priv *p, 97 int reg) 98 { 99 struct intc_irqpin_iomem *i = &p->iomem[reg]; 100 101 return i->read(i->iomem); 102 } 103 104 static inline void intc_irqpin_write(struct intc_irqpin_priv *p, 105 int reg, unsigned long data) 106 { 107 struct intc_irqpin_iomem *i = &p->iomem[reg]; 108 109 i->write(i->iomem, data); 110 } 111 112 static inline unsigned long intc_irqpin_hwirq_mask(struct intc_irqpin_priv *p, 113 int reg, int hw_irq) 114 { 115 return BIT((p->iomem[reg].width - 1) - hw_irq); 116 } 117 118 static inline void intc_irqpin_irq_write_hwirq(struct intc_irqpin_priv *p, 119 int reg, int hw_irq) 120 { 121 intc_irqpin_write(p, reg, intc_irqpin_hwirq_mask(p, reg, hw_irq)); 122 } 123 124 static DEFINE_RAW_SPINLOCK(intc_irqpin_lock); /* only used by slow path */ 125 126 static void intc_irqpin_read_modify_write(struct intc_irqpin_priv *p, 127 int reg, int shift, 128 int width, int value) 129 { 130 unsigned long flags; 131 unsigned long tmp; 132 133 raw_spin_lock_irqsave(&intc_irqpin_lock, flags); 134 135 tmp = intc_irqpin_read(p, reg); 136 tmp &= ~(((1 << width) - 1) << shift); 137 tmp |= value << shift; 138 intc_irqpin_write(p, reg, tmp); 139 140 raw_spin_unlock_irqrestore(&intc_irqpin_lock, flags); 141 } 142 143 static void intc_irqpin_mask_unmask_prio(struct intc_irqpin_priv *p, 144 int irq, int do_mask) 145 { 146 /* The PRIO register is assumed to be 32-bit with fixed 4-bit fields. */ 147 int bitfield_width = 4; 148 int shift = 32 - (irq + 1) * bitfield_width; 149 150 intc_irqpin_read_modify_write(p, INTC_IRQPIN_REG_PRIO, 151 shift, bitfield_width, 152 do_mask ? 0 : (1 << bitfield_width) - 1); 153 } 154 155 static int intc_irqpin_set_sense(struct intc_irqpin_priv *p, int irq, int value) 156 { 157 /* The SENSE register is assumed to be 32-bit. */ 158 int bitfield_width = p->sense_bitfield_width; 159 int shift = 32 - (irq + 1) * bitfield_width; 160 161 dev_dbg(&p->pdev->dev, "sense irq = %d, mode = %d\n", irq, value); 162 163 if (value >= (1 << bitfield_width)) 164 return -EINVAL; 165 166 intc_irqpin_read_modify_write(p, INTC_IRQPIN_REG_SENSE, shift, 167 bitfield_width, value); 168 return 0; 169 } 170 171 static void intc_irqpin_dbg(struct intc_irqpin_irq *i, char *str) 172 { 173 dev_dbg(&i->p->pdev->dev, "%s (%d:%d:%d)\n", 174 str, i->requested_irq, i->hw_irq, i->domain_irq); 175 } 176 177 static void intc_irqpin_irq_enable(struct irq_data *d) 178 { 179 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 180 int hw_irq = irqd_to_hwirq(d); 181 182 intc_irqpin_dbg(&p->irq[hw_irq], "enable"); 183 intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_CLEAR, hw_irq); 184 } 185 186 static void intc_irqpin_irq_disable(struct irq_data *d) 187 { 188 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 189 int hw_irq = irqd_to_hwirq(d); 190 191 intc_irqpin_dbg(&p->irq[hw_irq], "disable"); 192 intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_MASK, hw_irq); 193 } 194 195 static void intc_irqpin_shared_irq_enable(struct irq_data *d) 196 { 197 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 198 int hw_irq = irqd_to_hwirq(d); 199 200 intc_irqpin_dbg(&p->irq[hw_irq], "shared enable"); 201 intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_CLEAR, hw_irq); 202 203 p->shared_irq_mask &= ~BIT(hw_irq); 204 } 205 206 static void intc_irqpin_shared_irq_disable(struct irq_data *d) 207 { 208 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 209 int hw_irq = irqd_to_hwirq(d); 210 211 intc_irqpin_dbg(&p->irq[hw_irq], "shared disable"); 212 intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_MASK, hw_irq); 213 214 p->shared_irq_mask |= BIT(hw_irq); 215 } 216 217 static void intc_irqpin_irq_enable_force(struct irq_data *d) 218 { 219 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 220 int irq = p->irq[irqd_to_hwirq(d)].requested_irq; 221 222 intc_irqpin_irq_enable(d); 223 224 /* enable interrupt through parent interrupt controller, 225 * assumes non-shared interrupt with 1:1 mapping 226 * needed for busted IRQs on some SoCs like sh73a0 227 */ 228 irq_get_chip(irq)->irq_unmask(irq_get_irq_data(irq)); 229 } 230 231 static void intc_irqpin_irq_disable_force(struct irq_data *d) 232 { 233 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 234 int irq = p->irq[irqd_to_hwirq(d)].requested_irq; 235 236 /* disable interrupt through parent interrupt controller, 237 * assumes non-shared interrupt with 1:1 mapping 238 * needed for busted IRQs on some SoCs like sh73a0 239 */ 240 irq_get_chip(irq)->irq_mask(irq_get_irq_data(irq)); 241 intc_irqpin_irq_disable(d); 242 } 243 244 #define INTC_IRQ_SENSE_VALID 0x10 245 #define INTC_IRQ_SENSE(x) (x + INTC_IRQ_SENSE_VALID) 246 247 static unsigned char intc_irqpin_sense[IRQ_TYPE_SENSE_MASK + 1] = { 248 [IRQ_TYPE_EDGE_FALLING] = INTC_IRQ_SENSE(0x00), 249 [IRQ_TYPE_EDGE_RISING] = INTC_IRQ_SENSE(0x01), 250 [IRQ_TYPE_LEVEL_LOW] = INTC_IRQ_SENSE(0x02), 251 [IRQ_TYPE_LEVEL_HIGH] = INTC_IRQ_SENSE(0x03), 252 [IRQ_TYPE_EDGE_BOTH] = INTC_IRQ_SENSE(0x04), 253 }; 254 255 static int intc_irqpin_irq_set_type(struct irq_data *d, unsigned int type) 256 { 257 unsigned char value = intc_irqpin_sense[type & IRQ_TYPE_SENSE_MASK]; 258 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 259 260 if (!(value & INTC_IRQ_SENSE_VALID)) 261 return -EINVAL; 262 263 return intc_irqpin_set_sense(p, irqd_to_hwirq(d), 264 value ^ INTC_IRQ_SENSE_VALID); 265 } 266 267 static int intc_irqpin_irq_set_wake(struct irq_data *d, unsigned int on) 268 { 269 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 270 int hw_irq = irqd_to_hwirq(d); 271 272 irq_set_irq_wake(p->irq[hw_irq].requested_irq, on); 273 if (on) 274 atomic_inc(&p->wakeup_path); 275 else 276 atomic_dec(&p->wakeup_path); 277 278 return 0; 279 } 280 281 static irqreturn_t intc_irqpin_irq_handler(int irq, void *dev_id) 282 { 283 struct intc_irqpin_irq *i = dev_id; 284 struct intc_irqpin_priv *p = i->p; 285 unsigned long bit; 286 287 intc_irqpin_dbg(i, "demux1"); 288 bit = intc_irqpin_hwirq_mask(p, INTC_IRQPIN_REG_SOURCE, i->hw_irq); 289 290 if (intc_irqpin_read(p, INTC_IRQPIN_REG_SOURCE) & bit) { 291 intc_irqpin_write(p, INTC_IRQPIN_REG_SOURCE, ~bit); 292 intc_irqpin_dbg(i, "demux2"); 293 generic_handle_irq(i->domain_irq); 294 return IRQ_HANDLED; 295 } 296 return IRQ_NONE; 297 } 298 299 static irqreturn_t intc_irqpin_shared_irq_handler(int irq, void *dev_id) 300 { 301 struct intc_irqpin_priv *p = dev_id; 302 unsigned int reg_source = intc_irqpin_read(p, INTC_IRQPIN_REG_SOURCE); 303 irqreturn_t status = IRQ_NONE; 304 int k; 305 306 for (k = 0; k < 8; k++) { 307 if (reg_source & BIT(7 - k)) { 308 if (BIT(k) & p->shared_irq_mask) 309 continue; 310 311 status |= intc_irqpin_irq_handler(irq, &p->irq[k]); 312 } 313 } 314 315 return status; 316 } 317 318 /* 319 * This lock class tells lockdep that INTC External IRQ Pin irqs are in a 320 * different category than their parents, so it won't report false recursion. 321 */ 322 static struct lock_class_key intc_irqpin_irq_lock_class; 323 324 /* And this is for the request mutex */ 325 static struct lock_class_key intc_irqpin_irq_request_class; 326 327 static int intc_irqpin_irq_domain_map(struct irq_domain *h, unsigned int virq, 328 irq_hw_number_t hw) 329 { 330 struct intc_irqpin_priv *p = h->host_data; 331 332 p->irq[hw].domain_irq = virq; 333 p->irq[hw].hw_irq = hw; 334 335 intc_irqpin_dbg(&p->irq[hw], "map"); 336 irq_set_chip_data(virq, h->host_data); 337 irq_set_lockdep_class(virq, &intc_irqpin_irq_lock_class, 338 &intc_irqpin_irq_request_class); 339 irq_set_chip_and_handler(virq, &p->irq_chip, handle_level_irq); 340 return 0; 341 } 342 343 static const struct irq_domain_ops intc_irqpin_irq_domain_ops = { 344 .map = intc_irqpin_irq_domain_map, 345 .xlate = irq_domain_xlate_twocell, 346 }; 347 348 static const struct intc_irqpin_config intc_irqpin_irlm_r8a777x = { 349 .irlm_bit = 23, /* ICR0.IRLM0 */ 350 }; 351 352 static const struct intc_irqpin_config intc_irqpin_rmobile = { 353 .irlm_bit = -1, 354 }; 355 356 static const struct of_device_id intc_irqpin_dt_ids[] = { 357 { .compatible = "renesas,intc-irqpin", }, 358 { .compatible = "renesas,intc-irqpin-r8a7778", 359 .data = &intc_irqpin_irlm_r8a777x }, 360 { .compatible = "renesas,intc-irqpin-r8a7779", 361 .data = &intc_irqpin_irlm_r8a777x }, 362 { .compatible = "renesas,intc-irqpin-r8a7740", 363 .data = &intc_irqpin_rmobile }, 364 { .compatible = "renesas,intc-irqpin-sh73a0", 365 .data = &intc_irqpin_rmobile }, 366 {}, 367 }; 368 MODULE_DEVICE_TABLE(of, intc_irqpin_dt_ids); 369 370 static int intc_irqpin_probe(struct platform_device *pdev) 371 { 372 const struct intc_irqpin_config *config; 373 struct device *dev = &pdev->dev; 374 struct intc_irqpin_priv *p; 375 struct intc_irqpin_iomem *i; 376 struct resource *io[INTC_IRQPIN_REG_NR]; 377 struct irq_chip *irq_chip; 378 void (*enable_fn)(struct irq_data *d); 379 void (*disable_fn)(struct irq_data *d); 380 const char *name = dev_name(dev); 381 bool control_parent; 382 unsigned int nirqs; 383 int ref_irq; 384 int ret; 385 int k; 386 387 p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL); 388 if (!p) 389 return -ENOMEM; 390 391 /* deal with driver instance configuration */ 392 of_property_read_u32(dev->of_node, "sense-bitfield-width", 393 &p->sense_bitfield_width); 394 control_parent = of_property_read_bool(dev->of_node, "control-parent"); 395 if (!p->sense_bitfield_width) 396 p->sense_bitfield_width = 4; /* default to 4 bits */ 397 398 p->pdev = pdev; 399 platform_set_drvdata(pdev, p); 400 401 config = of_device_get_match_data(dev); 402 403 pm_runtime_enable(dev); 404 pm_runtime_get_sync(dev); 405 406 /* get hold of register banks */ 407 memset(io, 0, sizeof(io)); 408 for (k = 0; k < INTC_IRQPIN_REG_NR; k++) { 409 io[k] = platform_get_resource(pdev, IORESOURCE_MEM, k); 410 if (!io[k] && k < INTC_IRQPIN_REG_NR_MANDATORY) { 411 dev_err(dev, "not enough IOMEM resources\n"); 412 ret = -EINVAL; 413 goto err0; 414 } 415 } 416 417 /* allow any number of IRQs between 1 and INTC_IRQPIN_MAX */ 418 for (k = 0; k < INTC_IRQPIN_MAX; k++) { 419 ret = platform_get_irq_optional(pdev, k); 420 if (ret == -ENXIO) 421 break; 422 if (ret < 0) 423 goto err0; 424 425 p->irq[k].p = p; 426 p->irq[k].requested_irq = ret; 427 } 428 429 nirqs = k; 430 if (nirqs < 1) { 431 dev_err(dev, "not enough IRQ resources\n"); 432 ret = -EINVAL; 433 goto err0; 434 } 435 436 /* ioremap IOMEM and setup read/write callbacks */ 437 for (k = 0; k < INTC_IRQPIN_REG_NR; k++) { 438 i = &p->iomem[k]; 439 440 /* handle optional registers */ 441 if (!io[k]) 442 continue; 443 444 switch (resource_size(io[k])) { 445 case 1: 446 i->width = 8; 447 i->read = intc_irqpin_read8; 448 i->write = intc_irqpin_write8; 449 break; 450 case 4: 451 i->width = 32; 452 i->read = intc_irqpin_read32; 453 i->write = intc_irqpin_write32; 454 break; 455 default: 456 dev_err(dev, "IOMEM size mismatch\n"); 457 ret = -EINVAL; 458 goto err0; 459 } 460 461 i->iomem = devm_ioremap(dev, io[k]->start, 462 resource_size(io[k])); 463 if (!i->iomem) { 464 dev_err(dev, "failed to remap IOMEM\n"); 465 ret = -ENXIO; 466 goto err0; 467 } 468 } 469 470 /* configure "individual IRQ mode" where needed */ 471 if (config && config->irlm_bit >= 0) { 472 if (io[INTC_IRQPIN_REG_IRLM]) 473 intc_irqpin_read_modify_write(p, INTC_IRQPIN_REG_IRLM, 474 config->irlm_bit, 1, 1); 475 else 476 dev_warn(dev, "unable to select IRLM mode\n"); 477 } 478 479 /* mask all interrupts using priority */ 480 for (k = 0; k < nirqs; k++) 481 intc_irqpin_mask_unmask_prio(p, k, 1); 482 483 /* clear all pending interrupts */ 484 intc_irqpin_write(p, INTC_IRQPIN_REG_SOURCE, 0x0); 485 486 /* scan for shared interrupt lines */ 487 ref_irq = p->irq[0].requested_irq; 488 p->shared_irqs = 1; 489 for (k = 1; k < nirqs; k++) { 490 if (ref_irq != p->irq[k].requested_irq) { 491 p->shared_irqs = 0; 492 break; 493 } 494 } 495 496 /* use more severe masking method if requested */ 497 if (control_parent) { 498 enable_fn = intc_irqpin_irq_enable_force; 499 disable_fn = intc_irqpin_irq_disable_force; 500 } else if (!p->shared_irqs) { 501 enable_fn = intc_irqpin_irq_enable; 502 disable_fn = intc_irqpin_irq_disable; 503 } else { 504 enable_fn = intc_irqpin_shared_irq_enable; 505 disable_fn = intc_irqpin_shared_irq_disable; 506 } 507 508 irq_chip = &p->irq_chip; 509 irq_chip->name = "intc-irqpin"; 510 irq_chip->irq_mask = disable_fn; 511 irq_chip->irq_unmask = enable_fn; 512 irq_chip->irq_set_type = intc_irqpin_irq_set_type; 513 irq_chip->irq_set_wake = intc_irqpin_irq_set_wake; 514 irq_chip->flags = IRQCHIP_MASK_ON_SUSPEND; 515 516 p->irq_domain = irq_domain_add_simple(dev->of_node, nirqs, 0, 517 &intc_irqpin_irq_domain_ops, p); 518 if (!p->irq_domain) { 519 ret = -ENXIO; 520 dev_err(dev, "cannot initialize irq domain\n"); 521 goto err0; 522 } 523 524 irq_domain_set_pm_device(p->irq_domain, dev); 525 526 if (p->shared_irqs) { 527 /* request one shared interrupt */ 528 if (devm_request_irq(dev, p->irq[0].requested_irq, 529 intc_irqpin_shared_irq_handler, 530 IRQF_SHARED, name, p)) { 531 dev_err(dev, "failed to request low IRQ\n"); 532 ret = -ENOENT; 533 goto err1; 534 } 535 } else { 536 /* request interrupts one by one */ 537 for (k = 0; k < nirqs; k++) { 538 if (devm_request_irq(dev, p->irq[k].requested_irq, 539 intc_irqpin_irq_handler, 0, name, 540 &p->irq[k])) { 541 dev_err(dev, "failed to request low IRQ\n"); 542 ret = -ENOENT; 543 goto err1; 544 } 545 } 546 } 547 548 /* unmask all interrupts on prio level */ 549 for (k = 0; k < nirqs; k++) 550 intc_irqpin_mask_unmask_prio(p, k, 0); 551 552 dev_info(dev, "driving %d irqs\n", nirqs); 553 554 return 0; 555 556 err1: 557 irq_domain_remove(p->irq_domain); 558 err0: 559 pm_runtime_put(dev); 560 pm_runtime_disable(dev); 561 return ret; 562 } 563 564 static void intc_irqpin_remove(struct platform_device *pdev) 565 { 566 struct intc_irqpin_priv *p = platform_get_drvdata(pdev); 567 568 irq_domain_remove(p->irq_domain); 569 pm_runtime_put(&pdev->dev); 570 pm_runtime_disable(&pdev->dev); 571 } 572 573 static int __maybe_unused intc_irqpin_suspend(struct device *dev) 574 { 575 struct intc_irqpin_priv *p = dev_get_drvdata(dev); 576 577 if (atomic_read(&p->wakeup_path)) 578 device_set_wakeup_path(dev); 579 580 return 0; 581 } 582 583 static SIMPLE_DEV_PM_OPS(intc_irqpin_pm_ops, intc_irqpin_suspend, NULL); 584 585 static struct platform_driver intc_irqpin_device_driver = { 586 .probe = intc_irqpin_probe, 587 .remove_new = intc_irqpin_remove, 588 .driver = { 589 .name = "renesas_intc_irqpin", 590 .of_match_table = intc_irqpin_dt_ids, 591 .pm = &intc_irqpin_pm_ops, 592 } 593 }; 594 595 static int __init intc_irqpin_init(void) 596 { 597 return platform_driver_register(&intc_irqpin_device_driver); 598 } 599 postcore_initcall(intc_irqpin_init); 600 601 static void __exit intc_irqpin_exit(void) 602 { 603 platform_driver_unregister(&intc_irqpin_device_driver); 604 } 605 module_exit(intc_irqpin_exit); 606 607 MODULE_AUTHOR("Magnus Damm"); 608 MODULE_DESCRIPTION("Renesas INTC External IRQ Pin Driver"); 609