1 /* 2 * Renesas INTC External IRQ Pin Driver 3 * 4 * Copyright (C) 2013 Magnus Damm 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 18 */ 19 20 #include <linux/clk.h> 21 #include <linux/init.h> 22 #include <linux/of.h> 23 #include <linux/platform_device.h> 24 #include <linux/spinlock.h> 25 #include <linux/interrupt.h> 26 #include <linux/ioport.h> 27 #include <linux/io.h> 28 #include <linux/irq.h> 29 #include <linux/irqdomain.h> 30 #include <linux/err.h> 31 #include <linux/slab.h> 32 #include <linux/module.h> 33 #include <linux/of_device.h> 34 #include <linux/platform_data/irq-renesas-intc-irqpin.h> 35 #include <linux/pm_runtime.h> 36 37 #define INTC_IRQPIN_MAX 8 /* maximum 8 interrupts per driver instance */ 38 39 #define INTC_IRQPIN_REG_SENSE 0 /* ICRn */ 40 #define INTC_IRQPIN_REG_PRIO 1 /* INTPRInn */ 41 #define INTC_IRQPIN_REG_SOURCE 2 /* INTREQnn */ 42 #define INTC_IRQPIN_REG_MASK 3 /* INTMSKnn */ 43 #define INTC_IRQPIN_REG_CLEAR 4 /* INTMSKCLRnn */ 44 #define INTC_IRQPIN_REG_NR_MANDATORY 5 45 #define INTC_IRQPIN_REG_IRLM 5 /* ICR0 with IRLM bit (optional) */ 46 #define INTC_IRQPIN_REG_NR 6 47 48 /* INTC external IRQ PIN hardware register access: 49 * 50 * SENSE is read-write 32-bit with 2-bits or 4-bits per IRQ (*) 51 * PRIO is read-write 32-bit with 4-bits per IRQ (**) 52 * SOURCE is read-only 32-bit or 8-bit with 1-bit per IRQ (***) 53 * MASK is write-only 32-bit or 8-bit with 1-bit per IRQ (***) 54 * CLEAR is write-only 32-bit or 8-bit with 1-bit per IRQ (***) 55 * 56 * (*) May be accessed by more than one driver instance - lock needed 57 * (**) Read-modify-write access by one driver instance - lock needed 58 * (***) Accessed by one driver instance only - no locking needed 59 */ 60 61 struct intc_irqpin_iomem { 62 void __iomem *iomem; 63 unsigned long (*read)(void __iomem *iomem); 64 void (*write)(void __iomem *iomem, unsigned long data); 65 int width; 66 }; 67 68 struct intc_irqpin_irq { 69 int hw_irq; 70 int requested_irq; 71 int domain_irq; 72 struct intc_irqpin_priv *p; 73 }; 74 75 struct intc_irqpin_priv { 76 struct intc_irqpin_iomem iomem[INTC_IRQPIN_REG_NR]; 77 struct intc_irqpin_irq irq[INTC_IRQPIN_MAX]; 78 struct renesas_intc_irqpin_config config; 79 unsigned int number_of_irqs; 80 struct platform_device *pdev; 81 struct irq_chip irq_chip; 82 struct irq_domain *irq_domain; 83 struct clk *clk; 84 bool shared_irqs; 85 u8 shared_irq_mask; 86 }; 87 88 struct intc_irqpin_irlm_config { 89 unsigned int irlm_bit; 90 }; 91 92 static unsigned long intc_irqpin_read32(void __iomem *iomem) 93 { 94 return ioread32(iomem); 95 } 96 97 static unsigned long intc_irqpin_read8(void __iomem *iomem) 98 { 99 return ioread8(iomem); 100 } 101 102 static void intc_irqpin_write32(void __iomem *iomem, unsigned long data) 103 { 104 iowrite32(data, iomem); 105 } 106 107 static void intc_irqpin_write8(void __iomem *iomem, unsigned long data) 108 { 109 iowrite8(data, iomem); 110 } 111 112 static inline unsigned long intc_irqpin_read(struct intc_irqpin_priv *p, 113 int reg) 114 { 115 struct intc_irqpin_iomem *i = &p->iomem[reg]; 116 117 return i->read(i->iomem); 118 } 119 120 static inline void intc_irqpin_write(struct intc_irqpin_priv *p, 121 int reg, unsigned long data) 122 { 123 struct intc_irqpin_iomem *i = &p->iomem[reg]; 124 125 i->write(i->iomem, data); 126 } 127 128 static inline unsigned long intc_irqpin_hwirq_mask(struct intc_irqpin_priv *p, 129 int reg, int hw_irq) 130 { 131 return BIT((p->iomem[reg].width - 1) - hw_irq); 132 } 133 134 static inline void intc_irqpin_irq_write_hwirq(struct intc_irqpin_priv *p, 135 int reg, int hw_irq) 136 { 137 intc_irqpin_write(p, reg, intc_irqpin_hwirq_mask(p, reg, hw_irq)); 138 } 139 140 static DEFINE_RAW_SPINLOCK(intc_irqpin_lock); /* only used by slow path */ 141 142 static void intc_irqpin_read_modify_write(struct intc_irqpin_priv *p, 143 int reg, int shift, 144 int width, int value) 145 { 146 unsigned long flags; 147 unsigned long tmp; 148 149 raw_spin_lock_irqsave(&intc_irqpin_lock, flags); 150 151 tmp = intc_irqpin_read(p, reg); 152 tmp &= ~(((1 << width) - 1) << shift); 153 tmp |= value << shift; 154 intc_irqpin_write(p, reg, tmp); 155 156 raw_spin_unlock_irqrestore(&intc_irqpin_lock, flags); 157 } 158 159 static void intc_irqpin_mask_unmask_prio(struct intc_irqpin_priv *p, 160 int irq, int do_mask) 161 { 162 /* The PRIO register is assumed to be 32-bit with fixed 4-bit fields. */ 163 int bitfield_width = 4; 164 int shift = 32 - (irq + 1) * bitfield_width; 165 166 intc_irqpin_read_modify_write(p, INTC_IRQPIN_REG_PRIO, 167 shift, bitfield_width, 168 do_mask ? 0 : (1 << bitfield_width) - 1); 169 } 170 171 static int intc_irqpin_set_sense(struct intc_irqpin_priv *p, int irq, int value) 172 { 173 /* The SENSE register is assumed to be 32-bit. */ 174 int bitfield_width = p->config.sense_bitfield_width; 175 int shift = 32 - (irq + 1) * bitfield_width; 176 177 dev_dbg(&p->pdev->dev, "sense irq = %d, mode = %d\n", irq, value); 178 179 if (value >= (1 << bitfield_width)) 180 return -EINVAL; 181 182 intc_irqpin_read_modify_write(p, INTC_IRQPIN_REG_SENSE, shift, 183 bitfield_width, value); 184 return 0; 185 } 186 187 static void intc_irqpin_dbg(struct intc_irqpin_irq *i, char *str) 188 { 189 dev_dbg(&i->p->pdev->dev, "%s (%d:%d:%d)\n", 190 str, i->requested_irq, i->hw_irq, i->domain_irq); 191 } 192 193 static void intc_irqpin_irq_enable(struct irq_data *d) 194 { 195 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 196 int hw_irq = irqd_to_hwirq(d); 197 198 intc_irqpin_dbg(&p->irq[hw_irq], "enable"); 199 intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_CLEAR, hw_irq); 200 } 201 202 static void intc_irqpin_irq_disable(struct irq_data *d) 203 { 204 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 205 int hw_irq = irqd_to_hwirq(d); 206 207 intc_irqpin_dbg(&p->irq[hw_irq], "disable"); 208 intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_MASK, hw_irq); 209 } 210 211 static void intc_irqpin_shared_irq_enable(struct irq_data *d) 212 { 213 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 214 int hw_irq = irqd_to_hwirq(d); 215 216 intc_irqpin_dbg(&p->irq[hw_irq], "shared enable"); 217 intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_CLEAR, hw_irq); 218 219 p->shared_irq_mask &= ~BIT(hw_irq); 220 } 221 222 static void intc_irqpin_shared_irq_disable(struct irq_data *d) 223 { 224 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 225 int hw_irq = irqd_to_hwirq(d); 226 227 intc_irqpin_dbg(&p->irq[hw_irq], "shared disable"); 228 intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_MASK, hw_irq); 229 230 p->shared_irq_mask |= BIT(hw_irq); 231 } 232 233 static void intc_irqpin_irq_enable_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 intc_irqpin_irq_enable(d); 239 240 /* enable interrupt through parent interrupt controller, 241 * assumes non-shared interrupt with 1:1 mapping 242 * needed for busted IRQs on some SoCs like sh73a0 243 */ 244 irq_get_chip(irq)->irq_unmask(irq_get_irq_data(irq)); 245 } 246 247 static void intc_irqpin_irq_disable_force(struct irq_data *d) 248 { 249 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 250 int irq = p->irq[irqd_to_hwirq(d)].requested_irq; 251 252 /* disable interrupt through parent interrupt controller, 253 * assumes non-shared interrupt with 1:1 mapping 254 * needed for busted IRQs on some SoCs like sh73a0 255 */ 256 irq_get_chip(irq)->irq_mask(irq_get_irq_data(irq)); 257 intc_irqpin_irq_disable(d); 258 } 259 260 #define INTC_IRQ_SENSE_VALID 0x10 261 #define INTC_IRQ_SENSE(x) (x + INTC_IRQ_SENSE_VALID) 262 263 static unsigned char intc_irqpin_sense[IRQ_TYPE_SENSE_MASK + 1] = { 264 [IRQ_TYPE_EDGE_FALLING] = INTC_IRQ_SENSE(0x00), 265 [IRQ_TYPE_EDGE_RISING] = INTC_IRQ_SENSE(0x01), 266 [IRQ_TYPE_LEVEL_LOW] = INTC_IRQ_SENSE(0x02), 267 [IRQ_TYPE_LEVEL_HIGH] = INTC_IRQ_SENSE(0x03), 268 [IRQ_TYPE_EDGE_BOTH] = INTC_IRQ_SENSE(0x04), 269 }; 270 271 static int intc_irqpin_irq_set_type(struct irq_data *d, unsigned int type) 272 { 273 unsigned char value = intc_irqpin_sense[type & IRQ_TYPE_SENSE_MASK]; 274 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 275 276 if (!(value & INTC_IRQ_SENSE_VALID)) 277 return -EINVAL; 278 279 return intc_irqpin_set_sense(p, irqd_to_hwirq(d), 280 value ^ INTC_IRQ_SENSE_VALID); 281 } 282 283 static int intc_irqpin_irq_set_wake(struct irq_data *d, unsigned int on) 284 { 285 struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); 286 287 if (!p->clk) 288 return 0; 289 290 if (on) 291 clk_enable(p->clk); 292 else 293 clk_disable(p->clk); 294 295 return 0; 296 } 297 298 static irqreturn_t intc_irqpin_irq_handler(int irq, void *dev_id) 299 { 300 struct intc_irqpin_irq *i = dev_id; 301 struct intc_irqpin_priv *p = i->p; 302 unsigned long bit; 303 304 intc_irqpin_dbg(i, "demux1"); 305 bit = intc_irqpin_hwirq_mask(p, INTC_IRQPIN_REG_SOURCE, i->hw_irq); 306 307 if (intc_irqpin_read(p, INTC_IRQPIN_REG_SOURCE) & bit) { 308 intc_irqpin_write(p, INTC_IRQPIN_REG_SOURCE, ~bit); 309 intc_irqpin_dbg(i, "demux2"); 310 generic_handle_irq(i->domain_irq); 311 return IRQ_HANDLED; 312 } 313 return IRQ_NONE; 314 } 315 316 static irqreturn_t intc_irqpin_shared_irq_handler(int irq, void *dev_id) 317 { 318 struct intc_irqpin_priv *p = dev_id; 319 unsigned int reg_source = intc_irqpin_read(p, INTC_IRQPIN_REG_SOURCE); 320 irqreturn_t status = IRQ_NONE; 321 int k; 322 323 for (k = 0; k < 8; k++) { 324 if (reg_source & BIT(7 - k)) { 325 if (BIT(k) & p->shared_irq_mask) 326 continue; 327 328 status |= intc_irqpin_irq_handler(irq, &p->irq[k]); 329 } 330 } 331 332 return status; 333 } 334 335 static int intc_irqpin_irq_domain_map(struct irq_domain *h, unsigned int virq, 336 irq_hw_number_t hw) 337 { 338 struct intc_irqpin_priv *p = h->host_data; 339 340 p->irq[hw].domain_irq = virq; 341 p->irq[hw].hw_irq = hw; 342 343 intc_irqpin_dbg(&p->irq[hw], "map"); 344 irq_set_chip_data(virq, h->host_data); 345 irq_set_chip_and_handler(virq, &p->irq_chip, handle_level_irq); 346 set_irq_flags(virq, IRQF_VALID); /* kill me now */ 347 return 0; 348 } 349 350 static struct irq_domain_ops intc_irqpin_irq_domain_ops = { 351 .map = intc_irqpin_irq_domain_map, 352 .xlate = irq_domain_xlate_twocell, 353 }; 354 355 static const struct intc_irqpin_irlm_config intc_irqpin_irlm_r8a7779 = { 356 .irlm_bit = 23, /* ICR0.IRLM0 */ 357 }; 358 359 static const struct of_device_id intc_irqpin_dt_ids[] = { 360 { .compatible = "renesas,intc-irqpin", }, 361 { .compatible = "renesas,intc-irqpin-r8a7779", 362 .data = &intc_irqpin_irlm_r8a7779 }, 363 {}, 364 }; 365 MODULE_DEVICE_TABLE(of, intc_irqpin_dt_ids); 366 367 static int intc_irqpin_probe(struct platform_device *pdev) 368 { 369 struct device *dev = &pdev->dev; 370 struct renesas_intc_irqpin_config *pdata = dev->platform_data; 371 const struct of_device_id *of_id; 372 struct intc_irqpin_priv *p; 373 struct intc_irqpin_iomem *i; 374 struct resource *io[INTC_IRQPIN_REG_NR]; 375 struct resource *irq; 376 struct irq_chip *irq_chip; 377 void (*enable_fn)(struct irq_data *d); 378 void (*disable_fn)(struct irq_data *d); 379 const char *name = dev_name(dev); 380 int ref_irq; 381 int ret; 382 int k; 383 384 p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL); 385 if (!p) { 386 dev_err(dev, "failed to allocate driver data\n"); 387 return -ENOMEM; 388 } 389 390 /* deal with driver instance configuration */ 391 if (pdata) { 392 memcpy(&p->config, pdata, sizeof(*pdata)); 393 } else { 394 of_property_read_u32(dev->of_node, "sense-bitfield-width", 395 &p->config.sense_bitfield_width); 396 p->config.control_parent = of_property_read_bool(dev->of_node, 397 "control-parent"); 398 } 399 if (!p->config.sense_bitfield_width) 400 p->config.sense_bitfield_width = 4; /* default to 4 bits */ 401 402 p->pdev = pdev; 403 platform_set_drvdata(pdev, p); 404 405 p->clk = devm_clk_get(dev, NULL); 406 if (IS_ERR(p->clk)) { 407 dev_warn(dev, "unable to get clock\n"); 408 p->clk = NULL; 409 } 410 411 pm_runtime_enable(dev); 412 pm_runtime_get_sync(dev); 413 414 /* get hold of register banks */ 415 memset(io, 0, sizeof(io)); 416 for (k = 0; k < INTC_IRQPIN_REG_NR; k++) { 417 io[k] = platform_get_resource(pdev, IORESOURCE_MEM, k); 418 if (!io[k] && k < INTC_IRQPIN_REG_NR_MANDATORY) { 419 dev_err(dev, "not enough IOMEM resources\n"); 420 ret = -EINVAL; 421 goto err0; 422 } 423 } 424 425 /* allow any number of IRQs between 1 and INTC_IRQPIN_MAX */ 426 for (k = 0; k < INTC_IRQPIN_MAX; k++) { 427 irq = platform_get_resource(pdev, IORESOURCE_IRQ, k); 428 if (!irq) 429 break; 430 431 p->irq[k].p = p; 432 p->irq[k].requested_irq = irq->start; 433 } 434 435 p->number_of_irqs = k; 436 if (p->number_of_irqs < 1) { 437 dev_err(dev, "not enough IRQ resources\n"); 438 ret = -EINVAL; 439 goto err0; 440 } 441 442 /* ioremap IOMEM and setup read/write callbacks */ 443 for (k = 0; k < INTC_IRQPIN_REG_NR; k++) { 444 i = &p->iomem[k]; 445 446 /* handle optional registers */ 447 if (!io[k]) 448 continue; 449 450 switch (resource_size(io[k])) { 451 case 1: 452 i->width = 8; 453 i->read = intc_irqpin_read8; 454 i->write = intc_irqpin_write8; 455 break; 456 case 4: 457 i->width = 32; 458 i->read = intc_irqpin_read32; 459 i->write = intc_irqpin_write32; 460 break; 461 default: 462 dev_err(dev, "IOMEM size mismatch\n"); 463 ret = -EINVAL; 464 goto err0; 465 } 466 467 i->iomem = devm_ioremap_nocache(dev, io[k]->start, 468 resource_size(io[k])); 469 if (!i->iomem) { 470 dev_err(dev, "failed to remap IOMEM\n"); 471 ret = -ENXIO; 472 goto err0; 473 } 474 } 475 476 /* configure "individual IRQ mode" where needed */ 477 of_id = of_match_device(intc_irqpin_dt_ids, dev); 478 if (of_id && of_id->data) { 479 const struct intc_irqpin_irlm_config *irlm_config = of_id->data; 480 481 if (io[INTC_IRQPIN_REG_IRLM]) 482 intc_irqpin_read_modify_write(p, INTC_IRQPIN_REG_IRLM, 483 irlm_config->irlm_bit, 484 1, 1); 485 else 486 dev_warn(dev, "unable to select IRLM mode\n"); 487 } 488 489 /* mask all interrupts using priority */ 490 for (k = 0; k < p->number_of_irqs; k++) 491 intc_irqpin_mask_unmask_prio(p, k, 1); 492 493 /* clear all pending interrupts */ 494 intc_irqpin_write(p, INTC_IRQPIN_REG_SOURCE, 0x0); 495 496 /* scan for shared interrupt lines */ 497 ref_irq = p->irq[0].requested_irq; 498 p->shared_irqs = true; 499 for (k = 1; k < p->number_of_irqs; k++) { 500 if (ref_irq != p->irq[k].requested_irq) { 501 p->shared_irqs = false; 502 break; 503 } 504 } 505 506 /* use more severe masking method if requested */ 507 if (p->config.control_parent) { 508 enable_fn = intc_irqpin_irq_enable_force; 509 disable_fn = intc_irqpin_irq_disable_force; 510 } else if (!p->shared_irqs) { 511 enable_fn = intc_irqpin_irq_enable; 512 disable_fn = intc_irqpin_irq_disable; 513 } else { 514 enable_fn = intc_irqpin_shared_irq_enable; 515 disable_fn = intc_irqpin_shared_irq_disable; 516 } 517 518 irq_chip = &p->irq_chip; 519 irq_chip->name = name; 520 irq_chip->irq_mask = disable_fn; 521 irq_chip->irq_unmask = enable_fn; 522 irq_chip->irq_set_type = intc_irqpin_irq_set_type; 523 irq_chip->irq_set_wake = intc_irqpin_irq_set_wake; 524 irq_chip->flags = IRQCHIP_MASK_ON_SUSPEND; 525 526 p->irq_domain = irq_domain_add_simple(dev->of_node, 527 p->number_of_irqs, 528 p->config.irq_base, 529 &intc_irqpin_irq_domain_ops, p); 530 if (!p->irq_domain) { 531 ret = -ENXIO; 532 dev_err(dev, "cannot initialize irq domain\n"); 533 goto err0; 534 } 535 536 if (p->shared_irqs) { 537 /* request one shared interrupt */ 538 if (devm_request_irq(dev, p->irq[0].requested_irq, 539 intc_irqpin_shared_irq_handler, 540 IRQF_SHARED, name, p)) { 541 dev_err(dev, "failed to request low IRQ\n"); 542 ret = -ENOENT; 543 goto err1; 544 } 545 } else { 546 /* request interrupts one by one */ 547 for (k = 0; k < p->number_of_irqs; k++) { 548 if (devm_request_irq(dev, p->irq[k].requested_irq, 549 intc_irqpin_irq_handler, 0, name, 550 &p->irq[k])) { 551 dev_err(dev, "failed to request low IRQ\n"); 552 ret = -ENOENT; 553 goto err1; 554 } 555 } 556 } 557 558 /* unmask all interrupts on prio level */ 559 for (k = 0; k < p->number_of_irqs; k++) 560 intc_irqpin_mask_unmask_prio(p, k, 0); 561 562 dev_info(dev, "driving %d irqs\n", p->number_of_irqs); 563 564 /* warn in case of mismatch if irq base is specified */ 565 if (p->config.irq_base) { 566 if (p->config.irq_base != p->irq[0].domain_irq) 567 dev_warn(dev, "irq base mismatch (%d/%d)\n", 568 p->config.irq_base, p->irq[0].domain_irq); 569 } 570 571 return 0; 572 573 err1: 574 irq_domain_remove(p->irq_domain); 575 err0: 576 pm_runtime_put(dev); 577 pm_runtime_disable(dev); 578 return ret; 579 } 580 581 static int intc_irqpin_remove(struct platform_device *pdev) 582 { 583 struct intc_irqpin_priv *p = platform_get_drvdata(pdev); 584 585 irq_domain_remove(p->irq_domain); 586 pm_runtime_put(&pdev->dev); 587 pm_runtime_disable(&pdev->dev); 588 return 0; 589 } 590 591 static struct platform_driver intc_irqpin_device_driver = { 592 .probe = intc_irqpin_probe, 593 .remove = intc_irqpin_remove, 594 .driver = { 595 .name = "renesas_intc_irqpin", 596 .of_match_table = intc_irqpin_dt_ids, 597 } 598 }; 599 600 static int __init intc_irqpin_init(void) 601 { 602 return platform_driver_register(&intc_irqpin_device_driver); 603 } 604 postcore_initcall(intc_irqpin_init); 605 606 static void __exit intc_irqpin_exit(void) 607 { 608 platform_driver_unregister(&intc_irqpin_device_driver); 609 } 610 module_exit(intc_irqpin_exit); 611 612 MODULE_AUTHOR("Magnus Damm"); 613 MODULE_DESCRIPTION("Renesas INTC External IRQ Pin Driver"); 614 MODULE_LICENSE("GPL v2"); 615