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/of_device.h> 21 #include <linux/pm_runtime.h> 22 23 #define INTC_IRQPIN_MAX 8 /* maximum 8 interrupts per driver instance */ 24 25 #define INTC_IRQPIN_REG_SENSE 0 /* ICRn */ 26 #define INTC_IRQPIN_REG_PRIO 1 /* INTPRInn */ 27 #define INTC_IRQPIN_REG_SOURCE 2 /* INTREQnn */ 28 #define INTC_IRQPIN_REG_MASK 3 /* INTMSKnn */ 29 #define INTC_IRQPIN_REG_CLEAR 4 /* INTMSKCLRnn */ 30 #define INTC_IRQPIN_REG_NR_MANDATORY 5 31 #define INTC_IRQPIN_REG_IRLM 5 /* ICR0 with IRLM bit (optional) */ 32 #define INTC_IRQPIN_REG_NR 6 33 34 /* INTC external IRQ PIN hardware register access: 35 * 36 * SENSE is read-write 32-bit with 2-bits or 4-bits per IRQ (*) 37 * PRIO is read-write 32-bit with 4-bits per IRQ (**) 38 * SOURCE is read-only 32-bit or 8-bit with 1-bit per IRQ (***) 39 * MASK is write-only 32-bit or 8-bit with 1-bit per IRQ (***) 40 * CLEAR is write-only 32-bit or 8-bit with 1-bit per IRQ (***) 41 * 42 * (*) May be accessed by more than one driver instance - lock needed 43 * (**) Read-modify-write access by one driver instance - lock needed 44 * (***) Accessed by one driver instance only - no locking needed 45 */ 46 47 struct intc_irqpin_iomem { 48 void __iomem *iomem; 49 unsigned long (*read)(void __iomem *iomem); 50 void (*write)(void __iomem *iomem, unsigned long data); 51 int width; 52 }; 53 54 struct intc_irqpin_irq { 55 int hw_irq; 56 int requested_irq; 57 int domain_irq; 58 struct intc_irqpin_priv *p; 59 }; 60 61 struct intc_irqpin_priv { 62 struct intc_irqpin_iomem iomem[INTC_IRQPIN_REG_NR]; 63 struct intc_irqpin_irq irq[INTC_IRQPIN_MAX]; 64 unsigned int sense_bitfield_width; 65 struct platform_device *pdev; 66 struct irq_chip irq_chip; 67 struct irq_domain *irq_domain; 68 atomic_t wakeup_path; 69 unsigned shared_irqs:1; 70 u8 shared_irq_mask; 71 }; 72 73 struct intc_irqpin_config { 74 unsigned int irlm_bit; 75 unsigned needs_irlm:1; 76 }; 77 78 static unsigned long intc_irqpin_read32(void __iomem *iomem) 79 { 80 return ioread32(iomem); 81 } 82 83 static unsigned long intc_irqpin_read8(void __iomem *iomem) 84 { 85 return ioread8(iomem); 86 } 87 88 static void intc_irqpin_write32(void __iomem *iomem, unsigned long data) 89 { 90 iowrite32(data, iomem); 91 } 92 93 static void intc_irqpin_write8(void __iomem *iomem, unsigned long data) 94 { 95 iowrite8(data, iomem); 96 } 97 98 static inline unsigned long intc_irqpin_read(struct intc_irqpin_priv *p, 99 int reg) 100 { 101 struct intc_irqpin_iomem *i = &p->iomem[reg]; 102 103 return i->read(i->iomem); 104 } 105 106 static inline void intc_irqpin_write(struct intc_irqpin_priv *p, 107 int reg, unsigned long data) 108 { 109 struct intc_irqpin_iomem *i = &p->iomem[reg]; 110 111 i->write(i->iomem, data); 112 } 113 114 static inline unsigned long intc_irqpin_hwirq_mask(struct intc_irqpin_priv *p, 115 int reg, int hw_irq) 116 { 117 return BIT((p->iomem[reg].width - 1) - hw_irq); 118 } 119 120 static inline void intc_irqpin_irq_write_hwirq(struct intc_irqpin_priv *p, 121 int reg, int hw_irq) 122 { 123 intc_irqpin_write(p, reg, intc_irqpin_hwirq_mask(p, reg, hw_irq)); 124 } 125 126 static DEFINE_RAW_SPINLOCK(intc_irqpin_lock); /* only used by slow path */ 127 128 static void intc_irqpin_read_modify_write(struct intc_irqpin_priv *p, 129 int reg, int shift, 130 int width, int value) 131 { 132 unsigned long flags; 133 unsigned long tmp; 134 135 raw_spin_lock_irqsave(&intc_irqpin_lock, flags); 136 137 tmp = intc_irqpin_read(p, reg); 138 tmp &= ~(((1 << width) - 1) << shift); 139 tmp |= value << shift; 140 intc_irqpin_write(p, reg, tmp); 141 142 raw_spin_unlock_irqrestore(&intc_irqpin_lock, flags); 143 } 144 145 static void intc_irqpin_mask_unmask_prio(struct intc_irqpin_priv *p, 146 int irq, int do_mask) 147 { 148 /* The PRIO register is assumed to be 32-bit with fixed 4-bit fields. */ 149 int bitfield_width = 4; 150 int shift = 32 - (irq + 1) * bitfield_width; 151 152 intc_irqpin_read_modify_write(p, INTC_IRQPIN_REG_PRIO, 153 shift, bitfield_width, 154 do_mask ? 0 : (1 << bitfield_width) - 1); 155 } 156 157 static int intc_irqpin_set_sense(struct intc_irqpin_priv *p, int irq, int value) 158 { 159 /* The SENSE register is assumed to be 32-bit. */ 160 int bitfield_width = p->sense_bitfield_width; 161 int shift = 32 - (irq + 1) * bitfield_width; 162 163 dev_dbg(&p->pdev->dev, "sense irq = %d, mode = %d\n", irq, value); 164 165 if (value >= (1 << bitfield_width)) 166 return -EINVAL; 167 168 intc_irqpin_read_modify_write(p, INTC_IRQPIN_REG_SENSE, shift, 169 bitfield_width, value); 170 return 0; 171 } 172 173 static void intc_irqpin_dbg(struct intc_irqpin_irq *i, char *str) 174 { 175 dev_dbg(&i->p->pdev->dev, "%s (%d:%d:%d)\n", 176 str, i->requested_irq, i->hw_irq, i->domain_irq); 177 } 178 179 static void intc_irqpin_irq_enable(struct irq_data *d) 180 { 181 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 182 int hw_irq = irqd_to_hwirq(d); 183 184 intc_irqpin_dbg(&p->irq[hw_irq], "enable"); 185 intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_CLEAR, hw_irq); 186 } 187 188 static void intc_irqpin_irq_disable(struct irq_data *d) 189 { 190 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 191 int hw_irq = irqd_to_hwirq(d); 192 193 intc_irqpin_dbg(&p->irq[hw_irq], "disable"); 194 intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_MASK, hw_irq); 195 } 196 197 static void intc_irqpin_shared_irq_enable(struct irq_data *d) 198 { 199 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 200 int hw_irq = irqd_to_hwirq(d); 201 202 intc_irqpin_dbg(&p->irq[hw_irq], "shared enable"); 203 intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_CLEAR, hw_irq); 204 205 p->shared_irq_mask &= ~BIT(hw_irq); 206 } 207 208 static void intc_irqpin_shared_irq_disable(struct irq_data *d) 209 { 210 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 211 int hw_irq = irqd_to_hwirq(d); 212 213 intc_irqpin_dbg(&p->irq[hw_irq], "shared disable"); 214 intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_MASK, hw_irq); 215 216 p->shared_irq_mask |= BIT(hw_irq); 217 } 218 219 static void intc_irqpin_irq_enable_force(struct irq_data *d) 220 { 221 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 222 int irq = p->irq[irqd_to_hwirq(d)].requested_irq; 223 224 intc_irqpin_irq_enable(d); 225 226 /* enable interrupt through parent interrupt controller, 227 * assumes non-shared interrupt with 1:1 mapping 228 * needed for busted IRQs on some SoCs like sh73a0 229 */ 230 irq_get_chip(irq)->irq_unmask(irq_get_irq_data(irq)); 231 } 232 233 static void intc_irqpin_irq_disable_force(struct irq_data *d) 234 { 235 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 236 int irq = p->irq[irqd_to_hwirq(d)].requested_irq; 237 238 /* disable interrupt through parent interrupt controller, 239 * assumes non-shared interrupt with 1:1 mapping 240 * needed for busted IRQs on some SoCs like sh73a0 241 */ 242 irq_get_chip(irq)->irq_mask(irq_get_irq_data(irq)); 243 intc_irqpin_irq_disable(d); 244 } 245 246 #define INTC_IRQ_SENSE_VALID 0x10 247 #define INTC_IRQ_SENSE(x) (x + INTC_IRQ_SENSE_VALID) 248 249 static unsigned char intc_irqpin_sense[IRQ_TYPE_SENSE_MASK + 1] = { 250 [IRQ_TYPE_EDGE_FALLING] = INTC_IRQ_SENSE(0x00), 251 [IRQ_TYPE_EDGE_RISING] = INTC_IRQ_SENSE(0x01), 252 [IRQ_TYPE_LEVEL_LOW] = INTC_IRQ_SENSE(0x02), 253 [IRQ_TYPE_LEVEL_HIGH] = INTC_IRQ_SENSE(0x03), 254 [IRQ_TYPE_EDGE_BOTH] = INTC_IRQ_SENSE(0x04), 255 }; 256 257 static int intc_irqpin_irq_set_type(struct irq_data *d, unsigned int type) 258 { 259 unsigned char value = intc_irqpin_sense[type & IRQ_TYPE_SENSE_MASK]; 260 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 261 262 if (!(value & INTC_IRQ_SENSE_VALID)) 263 return -EINVAL; 264 265 return intc_irqpin_set_sense(p, irqd_to_hwirq(d), 266 value ^ INTC_IRQ_SENSE_VALID); 267 } 268 269 static int intc_irqpin_irq_set_wake(struct irq_data *d, unsigned int on) 270 { 271 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 272 int hw_irq = irqd_to_hwirq(d); 273 274 irq_set_irq_wake(p->irq[hw_irq].requested_irq, on); 275 if (on) 276 atomic_inc(&p->wakeup_path); 277 else 278 atomic_dec(&p->wakeup_path); 279 280 return 0; 281 } 282 283 static irqreturn_t intc_irqpin_irq_handler(int irq, void *dev_id) 284 { 285 struct intc_irqpin_irq *i = dev_id; 286 struct intc_irqpin_priv *p = i->p; 287 unsigned long bit; 288 289 intc_irqpin_dbg(i, "demux1"); 290 bit = intc_irqpin_hwirq_mask(p, INTC_IRQPIN_REG_SOURCE, i->hw_irq); 291 292 if (intc_irqpin_read(p, INTC_IRQPIN_REG_SOURCE) & bit) { 293 intc_irqpin_write(p, INTC_IRQPIN_REG_SOURCE, ~bit); 294 intc_irqpin_dbg(i, "demux2"); 295 generic_handle_irq(i->domain_irq); 296 return IRQ_HANDLED; 297 } 298 return IRQ_NONE; 299 } 300 301 static irqreturn_t intc_irqpin_shared_irq_handler(int irq, void *dev_id) 302 { 303 struct intc_irqpin_priv *p = dev_id; 304 unsigned int reg_source = intc_irqpin_read(p, INTC_IRQPIN_REG_SOURCE); 305 irqreturn_t status = IRQ_NONE; 306 int k; 307 308 for (k = 0; k < 8; k++) { 309 if (reg_source & BIT(7 - k)) { 310 if (BIT(k) & p->shared_irq_mask) 311 continue; 312 313 status |= intc_irqpin_irq_handler(irq, &p->irq[k]); 314 } 315 } 316 317 return status; 318 } 319 320 /* 321 * This lock class tells lockdep that INTC External IRQ Pin irqs are in a 322 * different category than their parents, so it won't report false recursion. 323 */ 324 static struct lock_class_key intc_irqpin_irq_lock_class; 325 326 /* And this is for the request mutex */ 327 static struct lock_class_key intc_irqpin_irq_request_class; 328 329 static int intc_irqpin_irq_domain_map(struct irq_domain *h, unsigned int virq, 330 irq_hw_number_t hw) 331 { 332 struct intc_irqpin_priv *p = h->host_data; 333 334 p->irq[hw].domain_irq = virq; 335 p->irq[hw].hw_irq = hw; 336 337 intc_irqpin_dbg(&p->irq[hw], "map"); 338 irq_set_chip_data(virq, h->host_data); 339 irq_set_lockdep_class(virq, &intc_irqpin_irq_lock_class, 340 &intc_irqpin_irq_request_class); 341 irq_set_chip_and_handler(virq, &p->irq_chip, handle_level_irq); 342 return 0; 343 } 344 345 static const struct irq_domain_ops intc_irqpin_irq_domain_ops = { 346 .map = intc_irqpin_irq_domain_map, 347 .xlate = irq_domain_xlate_twocell, 348 }; 349 350 static const struct intc_irqpin_config intc_irqpin_irlm_r8a777x = { 351 .irlm_bit = 23, /* ICR0.IRLM0 */ 352 .needs_irlm = 1, 353 }; 354 355 static const struct intc_irqpin_config intc_irqpin_rmobile = { 356 .needs_irlm = 0, 357 }; 358 359 static const struct of_device_id intc_irqpin_dt_ids[] = { 360 { .compatible = "renesas,intc-irqpin", }, 361 { .compatible = "renesas,intc-irqpin-r8a7778", 362 .data = &intc_irqpin_irlm_r8a777x }, 363 { .compatible = "renesas,intc-irqpin-r8a7779", 364 .data = &intc_irqpin_irlm_r8a777x }, 365 { .compatible = "renesas,intc-irqpin-r8a7740", 366 .data = &intc_irqpin_rmobile }, 367 { .compatible = "renesas,intc-irqpin-sh73a0", 368 .data = &intc_irqpin_rmobile }, 369 {}, 370 }; 371 MODULE_DEVICE_TABLE(of, intc_irqpin_dt_ids); 372 373 static int intc_irqpin_probe(struct platform_device *pdev) 374 { 375 const struct intc_irqpin_config *config; 376 struct device *dev = &pdev->dev; 377 struct intc_irqpin_priv *p; 378 struct intc_irqpin_iomem *i; 379 struct resource *io[INTC_IRQPIN_REG_NR]; 380 struct resource *irq; 381 struct irq_chip *irq_chip; 382 void (*enable_fn)(struct irq_data *d); 383 void (*disable_fn)(struct irq_data *d); 384 const char *name = dev_name(dev); 385 bool control_parent; 386 unsigned int nirqs; 387 int ref_irq; 388 int ret; 389 int k; 390 391 p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL); 392 if (!p) 393 return -ENOMEM; 394 395 /* deal with driver instance configuration */ 396 of_property_read_u32(dev->of_node, "sense-bitfield-width", 397 &p->sense_bitfield_width); 398 control_parent = of_property_read_bool(dev->of_node, "control-parent"); 399 if (!p->sense_bitfield_width) 400 p->sense_bitfield_width = 4; /* default to 4 bits */ 401 402 p->pdev = pdev; 403 platform_set_drvdata(pdev, p); 404 405 config = of_device_get_match_data(dev); 406 407 pm_runtime_enable(dev); 408 pm_runtime_get_sync(dev); 409 410 /* get hold of register banks */ 411 memset(io, 0, sizeof(io)); 412 for (k = 0; k < INTC_IRQPIN_REG_NR; k++) { 413 io[k] = platform_get_resource(pdev, IORESOURCE_MEM, k); 414 if (!io[k] && k < INTC_IRQPIN_REG_NR_MANDATORY) { 415 dev_err(dev, "not enough IOMEM resources\n"); 416 ret = -EINVAL; 417 goto err0; 418 } 419 } 420 421 /* allow any number of IRQs between 1 and INTC_IRQPIN_MAX */ 422 for (k = 0; k < INTC_IRQPIN_MAX; k++) { 423 irq = platform_get_resource(pdev, IORESOURCE_IRQ, k); 424 if (!irq) 425 break; 426 427 p->irq[k].p = p; 428 p->irq[k].requested_irq = irq->start; 429 } 430 431 nirqs = k; 432 if (nirqs < 1) { 433 dev_err(dev, "not enough IRQ resources\n"); 434 ret = -EINVAL; 435 goto err0; 436 } 437 438 /* ioremap IOMEM and setup read/write callbacks */ 439 for (k = 0; k < INTC_IRQPIN_REG_NR; k++) { 440 i = &p->iomem[k]; 441 442 /* handle optional registers */ 443 if (!io[k]) 444 continue; 445 446 switch (resource_size(io[k])) { 447 case 1: 448 i->width = 8; 449 i->read = intc_irqpin_read8; 450 i->write = intc_irqpin_write8; 451 break; 452 case 4: 453 i->width = 32; 454 i->read = intc_irqpin_read32; 455 i->write = intc_irqpin_write32; 456 break; 457 default: 458 dev_err(dev, "IOMEM size mismatch\n"); 459 ret = -EINVAL; 460 goto err0; 461 } 462 463 i->iomem = devm_ioremap(dev, io[k]->start, 464 resource_size(io[k])); 465 if (!i->iomem) { 466 dev_err(dev, "failed to remap IOMEM\n"); 467 ret = -ENXIO; 468 goto err0; 469 } 470 } 471 472 /* configure "individual IRQ mode" where needed */ 473 if (config && config->needs_irlm) { 474 if (io[INTC_IRQPIN_REG_IRLM]) 475 intc_irqpin_read_modify_write(p, INTC_IRQPIN_REG_IRLM, 476 config->irlm_bit, 1, 1); 477 else 478 dev_warn(dev, "unable to select IRLM mode\n"); 479 } 480 481 /* mask all interrupts using priority */ 482 for (k = 0; k < nirqs; k++) 483 intc_irqpin_mask_unmask_prio(p, k, 1); 484 485 /* clear all pending interrupts */ 486 intc_irqpin_write(p, INTC_IRQPIN_REG_SOURCE, 0x0); 487 488 /* scan for shared interrupt lines */ 489 ref_irq = p->irq[0].requested_irq; 490 p->shared_irqs = 1; 491 for (k = 1; k < nirqs; k++) { 492 if (ref_irq != p->irq[k].requested_irq) { 493 p->shared_irqs = 0; 494 break; 495 } 496 } 497 498 /* use more severe masking method if requested */ 499 if (control_parent) { 500 enable_fn = intc_irqpin_irq_enable_force; 501 disable_fn = intc_irqpin_irq_disable_force; 502 } else if (!p->shared_irqs) { 503 enable_fn = intc_irqpin_irq_enable; 504 disable_fn = intc_irqpin_irq_disable; 505 } else { 506 enable_fn = intc_irqpin_shared_irq_enable; 507 disable_fn = intc_irqpin_shared_irq_disable; 508 } 509 510 irq_chip = &p->irq_chip; 511 irq_chip->name = "intc-irqpin"; 512 irq_chip->parent_device = dev; 513 irq_chip->irq_mask = disable_fn; 514 irq_chip->irq_unmask = enable_fn; 515 irq_chip->irq_set_type = intc_irqpin_irq_set_type; 516 irq_chip->irq_set_wake = intc_irqpin_irq_set_wake; 517 irq_chip->flags = IRQCHIP_MASK_ON_SUSPEND; 518 519 p->irq_domain = irq_domain_add_simple(dev->of_node, nirqs, 0, 520 &intc_irqpin_irq_domain_ops, p); 521 if (!p->irq_domain) { 522 ret = -ENXIO; 523 dev_err(dev, "cannot initialize irq domain\n"); 524 goto err0; 525 } 526 527 if (p->shared_irqs) { 528 /* request one shared interrupt */ 529 if (devm_request_irq(dev, p->irq[0].requested_irq, 530 intc_irqpin_shared_irq_handler, 531 IRQF_SHARED, name, p)) { 532 dev_err(dev, "failed to request low IRQ\n"); 533 ret = -ENOENT; 534 goto err1; 535 } 536 } else { 537 /* request interrupts one by one */ 538 for (k = 0; k < nirqs; k++) { 539 if (devm_request_irq(dev, p->irq[k].requested_irq, 540 intc_irqpin_irq_handler, 0, name, 541 &p->irq[k])) { 542 dev_err(dev, "failed to request low IRQ\n"); 543 ret = -ENOENT; 544 goto err1; 545 } 546 } 547 } 548 549 /* unmask all interrupts on prio level */ 550 for (k = 0; k < nirqs; k++) 551 intc_irqpin_mask_unmask_prio(p, k, 0); 552 553 dev_info(dev, "driving %d irqs\n", nirqs); 554 555 return 0; 556 557 err1: 558 irq_domain_remove(p->irq_domain); 559 err0: 560 pm_runtime_put(dev); 561 pm_runtime_disable(dev); 562 return ret; 563 } 564 565 static int intc_irqpin_remove(struct platform_device *pdev) 566 { 567 struct intc_irqpin_priv *p = platform_get_drvdata(pdev); 568 569 irq_domain_remove(p->irq_domain); 570 pm_runtime_put(&pdev->dev); 571 pm_runtime_disable(&pdev->dev); 572 return 0; 573 } 574 575 static int __maybe_unused intc_irqpin_suspend(struct device *dev) 576 { 577 struct intc_irqpin_priv *p = dev_get_drvdata(dev); 578 579 if (atomic_read(&p->wakeup_path)) 580 device_set_wakeup_path(dev); 581 582 return 0; 583 } 584 585 static SIMPLE_DEV_PM_OPS(intc_irqpin_pm_ops, intc_irqpin_suspend, NULL); 586 587 static struct platform_driver intc_irqpin_device_driver = { 588 .probe = intc_irqpin_probe, 589 .remove = intc_irqpin_remove, 590 .driver = { 591 .name = "renesas_intc_irqpin", 592 .of_match_table = intc_irqpin_dt_ids, 593 .pm = &intc_irqpin_pm_ops, 594 } 595 }; 596 597 static int __init intc_irqpin_init(void) 598 { 599 return platform_driver_register(&intc_irqpin_device_driver); 600 } 601 postcore_initcall(intc_irqpin_init); 602 603 static void __exit intc_irqpin_exit(void) 604 { 605 platform_driver_unregister(&intc_irqpin_device_driver); 606 } 607 module_exit(intc_irqpin_exit); 608 609 MODULE_AUTHOR("Magnus Damm"); 610 MODULE_DESCRIPTION("Renesas INTC External IRQ Pin Driver"); 611 MODULE_LICENSE("GPL v2"); 612