1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * Copyright (C) 2014-2017 Broadcom 4 */ 5 6#include <linux/init.h> 7#include <linux/types.h> 8#include <linux/module.h> 9#include <linux/platform_device.h> 10#include <linux/interrupt.h> 11#include <linux/sysfs.h> 12#include <linux/io.h> 13#include <linux/string.h> 14#include <linux/device.h> 15#include <linux/list.h> 16#include <linux/of.h> 17#include <linux/bitops.h> 18#include <linux/pm.h> 19#include <linux/kernel.h> 20#include <linux/kdebug.h> 21#include <linux/notifier.h> 22 23#ifdef CONFIG_MIPS 24#include <asm/traps.h> 25#endif 26 27#define ARB_ERR_CAP_CLEAR (1 << 0) 28#define ARB_ERR_CAP_STATUS_TIMEOUT (1 << 12) 29#define ARB_ERR_CAP_STATUS_TEA (1 << 11) 30#define ARB_ERR_CAP_STATUS_WRITE (1 << 1) 31#define ARB_ERR_CAP_STATUS_VALID (1 << 0) 32 33#define ARB_BP_CAP_CLEAR (1 << 0) 34#define ARB_BP_CAP_STATUS_PROT_SHIFT 14 35#define ARB_BP_CAP_STATUS_TYPE (1 << 13) 36#define ARB_BP_CAP_STATUS_RSP_SHIFT 10 37#define ARB_BP_CAP_STATUS_MASK GENMASK(1, 0) 38#define ARB_BP_CAP_STATUS_BS_SHIFT 2 39#define ARB_BP_CAP_STATUS_WRITE (1 << 1) 40#define ARB_BP_CAP_STATUS_VALID (1 << 0) 41 42enum { 43 ARB_TIMER, 44 ARB_BP_CAP_CLR, 45 ARB_BP_CAP_HI_ADDR, 46 ARB_BP_CAP_ADDR, 47 ARB_BP_CAP_STATUS, 48 ARB_BP_CAP_MASTER, 49 ARB_ERR_CAP_CLR, 50 ARB_ERR_CAP_HI_ADDR, 51 ARB_ERR_CAP_ADDR, 52 ARB_ERR_CAP_STATUS, 53 ARB_ERR_CAP_MASTER, 54}; 55 56static const int gisb_offsets_bcm7038[] = { 57 [ARB_TIMER] = 0x00c, 58 [ARB_BP_CAP_CLR] = 0x014, 59 [ARB_BP_CAP_HI_ADDR] = -1, 60 [ARB_BP_CAP_ADDR] = 0x0b8, 61 [ARB_BP_CAP_STATUS] = 0x0c0, 62 [ARB_BP_CAP_MASTER] = -1, 63 [ARB_ERR_CAP_CLR] = 0x0c4, 64 [ARB_ERR_CAP_HI_ADDR] = -1, 65 [ARB_ERR_CAP_ADDR] = 0x0c8, 66 [ARB_ERR_CAP_STATUS] = 0x0d0, 67 [ARB_ERR_CAP_MASTER] = -1, 68}; 69 70static const int gisb_offsets_bcm7278[] = { 71 [ARB_TIMER] = 0x008, 72 [ARB_BP_CAP_CLR] = 0x01c, 73 [ARB_BP_CAP_HI_ADDR] = -1, 74 [ARB_BP_CAP_ADDR] = 0x220, 75 [ARB_BP_CAP_STATUS] = 0x230, 76 [ARB_BP_CAP_MASTER] = 0x234, 77 [ARB_ERR_CAP_CLR] = 0x7f8, 78 [ARB_ERR_CAP_HI_ADDR] = -1, 79 [ARB_ERR_CAP_ADDR] = 0x7e0, 80 [ARB_ERR_CAP_STATUS] = 0x7f0, 81 [ARB_ERR_CAP_MASTER] = 0x7f4, 82}; 83 84static const int gisb_offsets_bcm7400[] = { 85 [ARB_TIMER] = 0x00c, 86 [ARB_BP_CAP_CLR] = 0x014, 87 [ARB_BP_CAP_HI_ADDR] = -1, 88 [ARB_BP_CAP_ADDR] = 0x0b8, 89 [ARB_BP_CAP_STATUS] = 0x0c0, 90 [ARB_BP_CAP_MASTER] = 0x0c4, 91 [ARB_ERR_CAP_CLR] = 0x0c8, 92 [ARB_ERR_CAP_HI_ADDR] = -1, 93 [ARB_ERR_CAP_ADDR] = 0x0cc, 94 [ARB_ERR_CAP_STATUS] = 0x0d4, 95 [ARB_ERR_CAP_MASTER] = 0x0d8, 96}; 97 98static const int gisb_offsets_bcm7435[] = { 99 [ARB_TIMER] = 0x00c, 100 [ARB_BP_CAP_CLR] = 0x014, 101 [ARB_BP_CAP_HI_ADDR] = -1, 102 [ARB_BP_CAP_ADDR] = 0x158, 103 [ARB_BP_CAP_STATUS] = 0x160, 104 [ARB_BP_CAP_MASTER] = 0x164, 105 [ARB_ERR_CAP_CLR] = 0x168, 106 [ARB_ERR_CAP_HI_ADDR] = -1, 107 [ARB_ERR_CAP_ADDR] = 0x16c, 108 [ARB_ERR_CAP_STATUS] = 0x174, 109 [ARB_ERR_CAP_MASTER] = 0x178, 110}; 111 112static const int gisb_offsets_bcm7445[] = { 113 [ARB_TIMER] = 0x008, 114 [ARB_BP_CAP_CLR] = 0x010, 115 [ARB_BP_CAP_HI_ADDR] = -1, 116 [ARB_BP_CAP_ADDR] = 0x1d8, 117 [ARB_BP_CAP_STATUS] = 0x1e0, 118 [ARB_BP_CAP_MASTER] = 0x1e4, 119 [ARB_ERR_CAP_CLR] = 0x7e4, 120 [ARB_ERR_CAP_HI_ADDR] = 0x7e8, 121 [ARB_ERR_CAP_ADDR] = 0x7ec, 122 [ARB_ERR_CAP_STATUS] = 0x7f4, 123 [ARB_ERR_CAP_MASTER] = 0x7f8, 124}; 125 126struct brcmstb_gisb_arb_device { 127 void __iomem *base; 128 const int *gisb_offsets; 129 bool big_endian; 130 struct mutex lock; 131 struct list_head next; 132 u32 valid_mask; 133 const char *master_names[sizeof(u32) * BITS_PER_BYTE]; 134 u32 saved_timeout; 135}; 136 137static LIST_HEAD(brcmstb_gisb_arb_device_list); 138 139static u32 gisb_read(struct brcmstb_gisb_arb_device *gdev, int reg) 140{ 141 int offset = gdev->gisb_offsets[reg]; 142 143 if (offset < 0) { 144 /* return 1 if the hardware doesn't have ARB_ERR_CAP_MASTER */ 145 if (reg == ARB_ERR_CAP_MASTER) 146 return 1; 147 else 148 return 0; 149 } 150 151 if (gdev->big_endian) 152 return ioread32be(gdev->base + offset); 153 else 154 return ioread32(gdev->base + offset); 155} 156 157static u64 gisb_read_address(struct brcmstb_gisb_arb_device *gdev) 158{ 159 u64 value; 160 161 value = gisb_read(gdev, ARB_ERR_CAP_ADDR); 162 value |= (u64)gisb_read(gdev, ARB_ERR_CAP_HI_ADDR) << 32; 163 164 return value; 165} 166 167static u64 gisb_read_bp_address(struct brcmstb_gisb_arb_device *gdev) 168{ 169 u64 value; 170 171 value = gisb_read(gdev, ARB_BP_CAP_ADDR); 172 value |= (u64)gisb_read(gdev, ARB_BP_CAP_HI_ADDR) << 32; 173 174 return value; 175} 176 177static void gisb_write(struct brcmstb_gisb_arb_device *gdev, u32 val, int reg) 178{ 179 int offset = gdev->gisb_offsets[reg]; 180 181 if (offset == -1) 182 return; 183 184 if (gdev->big_endian) 185 iowrite32be(val, gdev->base + offset); 186 else 187 iowrite32(val, gdev->base + offset); 188} 189 190static ssize_t gisb_arb_get_timeout(struct device *dev, 191 struct device_attribute *attr, 192 char *buf) 193{ 194 struct brcmstb_gisb_arb_device *gdev = dev_get_drvdata(dev); 195 u32 timeout; 196 197 mutex_lock(&gdev->lock); 198 timeout = gisb_read(gdev, ARB_TIMER); 199 mutex_unlock(&gdev->lock); 200 201 return sprintf(buf, "%d", timeout); 202} 203 204static ssize_t gisb_arb_set_timeout(struct device *dev, 205 struct device_attribute *attr, 206 const char *buf, size_t count) 207{ 208 struct brcmstb_gisb_arb_device *gdev = dev_get_drvdata(dev); 209 int val, ret; 210 211 ret = kstrtoint(buf, 10, &val); 212 if (ret < 0) 213 return ret; 214 215 if (val == 0 || val >= 0xffffffff) 216 return -EINVAL; 217 218 mutex_lock(&gdev->lock); 219 gisb_write(gdev, val, ARB_TIMER); 220 mutex_unlock(&gdev->lock); 221 222 return count; 223} 224 225static const char * 226brcmstb_gisb_master_to_str(struct brcmstb_gisb_arb_device *gdev, 227 u32 masters) 228{ 229 u32 mask = gdev->valid_mask & masters; 230 231 if (hweight_long(mask) != 1) 232 return NULL; 233 234 return gdev->master_names[ffs(mask) - 1]; 235} 236 237static int brcmstb_gisb_arb_decode_addr(struct brcmstb_gisb_arb_device *gdev, 238 const char *reason) 239{ 240 u32 cap_status; 241 u64 arb_addr; 242 u32 master; 243 const char *m_name; 244 char m_fmt[11]; 245 246 cap_status = gisb_read(gdev, ARB_ERR_CAP_STATUS); 247 248 /* Invalid captured address, bail out */ 249 if (!(cap_status & ARB_ERR_CAP_STATUS_VALID)) 250 return 1; 251 252 /* Read the address and master */ 253 arb_addr = gisb_read_address(gdev); 254 master = gisb_read(gdev, ARB_ERR_CAP_MASTER); 255 256 m_name = brcmstb_gisb_master_to_str(gdev, master); 257 if (!m_name) { 258 snprintf(m_fmt, sizeof(m_fmt), "0x%08x", master); 259 m_name = m_fmt; 260 } 261 262 pr_crit("GISB: %s at 0x%llx [%c %s], core: %s\n", 263 reason, arb_addr, 264 cap_status & ARB_ERR_CAP_STATUS_WRITE ? 'W' : 'R', 265 cap_status & ARB_ERR_CAP_STATUS_TIMEOUT ? "timeout" : "", 266 m_name); 267 268 /* clear the GISB error */ 269 gisb_write(gdev, ARB_ERR_CAP_CLEAR, ARB_ERR_CAP_CLR); 270 271 return 0; 272} 273 274#ifdef CONFIG_MIPS 275static int brcmstb_bus_error_handler(struct pt_regs *regs, int is_fixup) 276{ 277 int ret = 0; 278 struct brcmstb_gisb_arb_device *gdev; 279 u32 cap_status; 280 281 list_for_each_entry(gdev, &brcmstb_gisb_arb_device_list, next) { 282 cap_status = gisb_read(gdev, ARB_ERR_CAP_STATUS); 283 284 /* Invalid captured address, bail out */ 285 if (!(cap_status & ARB_ERR_CAP_STATUS_VALID)) { 286 is_fixup = 1; 287 goto out; 288 } 289 290 ret |= brcmstb_gisb_arb_decode_addr(gdev, "bus error"); 291 } 292out: 293 return is_fixup ? MIPS_BE_FIXUP : MIPS_BE_FATAL; 294} 295#endif 296 297static irqreturn_t brcmstb_gisb_timeout_handler(int irq, void *dev_id) 298{ 299 brcmstb_gisb_arb_decode_addr(dev_id, "timeout"); 300 301 return IRQ_HANDLED; 302} 303 304static irqreturn_t brcmstb_gisb_tea_handler(int irq, void *dev_id) 305{ 306 brcmstb_gisb_arb_decode_addr(dev_id, "target abort"); 307 308 return IRQ_HANDLED; 309} 310 311static irqreturn_t brcmstb_gisb_bp_handler(int irq, void *dev_id) 312{ 313 struct brcmstb_gisb_arb_device *gdev = dev_id; 314 const char *m_name; 315 u32 bp_status; 316 u64 arb_addr; 317 u32 master; 318 char m_fmt[11]; 319 320 bp_status = gisb_read(gdev, ARB_BP_CAP_STATUS); 321 322 /* Invalid captured address, bail out */ 323 if (!(bp_status & ARB_BP_CAP_STATUS_VALID)) 324 return IRQ_HANDLED; 325 326 /* Read the address and master */ 327 arb_addr = gisb_read_bp_address(gdev); 328 master = gisb_read(gdev, ARB_BP_CAP_MASTER); 329 330 m_name = brcmstb_gisb_master_to_str(gdev, master); 331 if (!m_name) { 332 snprintf(m_fmt, sizeof(m_fmt), "0x%08x", master); 333 m_name = m_fmt; 334 } 335 336 pr_crit("GISB: breakpoint at 0x%llx [%c], core: %s\n", 337 arb_addr, bp_status & ARB_BP_CAP_STATUS_WRITE ? 'W' : 'R', 338 m_name); 339 340 /* clear the GISB error */ 341 gisb_write(gdev, ARB_ERR_CAP_CLEAR, ARB_ERR_CAP_CLR); 342 343 return IRQ_HANDLED; 344} 345 346/* 347 * Dump out gisb errors on die or panic. 348 */ 349static int dump_gisb_error(struct notifier_block *self, unsigned long v, 350 void *p); 351 352static struct notifier_block gisb_die_notifier = { 353 .notifier_call = dump_gisb_error, 354}; 355 356static struct notifier_block gisb_panic_notifier = { 357 .notifier_call = dump_gisb_error, 358}; 359 360static int dump_gisb_error(struct notifier_block *self, unsigned long v, 361 void *p) 362{ 363 struct brcmstb_gisb_arb_device *gdev; 364 const char *reason = "panic"; 365 366 if (self == &gisb_die_notifier) 367 reason = "die"; 368 369 /* iterate over each GISB arb registered handlers */ 370 list_for_each_entry(gdev, &brcmstb_gisb_arb_device_list, next) 371 brcmstb_gisb_arb_decode_addr(gdev, reason); 372 373 return NOTIFY_DONE; 374} 375 376static DEVICE_ATTR(gisb_arb_timeout, S_IWUSR | S_IRUGO, 377 gisb_arb_get_timeout, gisb_arb_set_timeout); 378 379static struct attribute *gisb_arb_sysfs_attrs[] = { 380 &dev_attr_gisb_arb_timeout.attr, 381 NULL, 382}; 383 384static struct attribute_group gisb_arb_sysfs_attr_group = { 385 .attrs = gisb_arb_sysfs_attrs, 386}; 387 388static const struct of_device_id brcmstb_gisb_arb_of_match[] = { 389 { .compatible = "brcm,gisb-arb", .data = gisb_offsets_bcm7445 }, 390 { .compatible = "brcm,bcm7445-gisb-arb", .data = gisb_offsets_bcm7445 }, 391 { .compatible = "brcm,bcm7435-gisb-arb", .data = gisb_offsets_bcm7435 }, 392 { .compatible = "brcm,bcm7400-gisb-arb", .data = gisb_offsets_bcm7400 }, 393 { .compatible = "brcm,bcm7278-gisb-arb", .data = gisb_offsets_bcm7278 }, 394 { .compatible = "brcm,bcm7038-gisb-arb", .data = gisb_offsets_bcm7038 }, 395 { }, 396}; 397 398static int __init brcmstb_gisb_arb_probe(struct platform_device *pdev) 399{ 400 struct device_node *dn = pdev->dev.of_node; 401 struct brcmstb_gisb_arb_device *gdev; 402 const struct of_device_id *of_id; 403 struct resource *r; 404 int err, timeout_irq, tea_irq, bp_irq; 405 unsigned int num_masters, j = 0; 406 int i, first, last; 407 408 r = platform_get_resource(pdev, IORESOURCE_MEM, 0); 409 timeout_irq = platform_get_irq(pdev, 0); 410 tea_irq = platform_get_irq(pdev, 1); 411 bp_irq = platform_get_irq(pdev, 2); 412 413 gdev = devm_kzalloc(&pdev->dev, sizeof(*gdev), GFP_KERNEL); 414 if (!gdev) 415 return -ENOMEM; 416 417 mutex_init(&gdev->lock); 418 INIT_LIST_HEAD(&gdev->next); 419 420 gdev->base = devm_ioremap_resource(&pdev->dev, r); 421 if (IS_ERR(gdev->base)) 422 return PTR_ERR(gdev->base); 423 424 of_id = of_match_node(brcmstb_gisb_arb_of_match, dn); 425 if (!of_id) { 426 pr_err("failed to look up compatible string\n"); 427 return -EINVAL; 428 } 429 gdev->gisb_offsets = of_id->data; 430 gdev->big_endian = of_device_is_big_endian(dn); 431 432 err = devm_request_irq(&pdev->dev, timeout_irq, 433 brcmstb_gisb_timeout_handler, 0, pdev->name, 434 gdev); 435 if (err < 0) 436 return err; 437 438 err = devm_request_irq(&pdev->dev, tea_irq, 439 brcmstb_gisb_tea_handler, 0, pdev->name, 440 gdev); 441 if (err < 0) 442 return err; 443 444 /* Interrupt is optional */ 445 if (bp_irq > 0) { 446 err = devm_request_irq(&pdev->dev, bp_irq, 447 brcmstb_gisb_bp_handler, 0, pdev->name, 448 gdev); 449 if (err < 0) 450 return err; 451 } 452 453 /* If we do not have a valid mask, assume all masters are enabled */ 454 if (of_property_read_u32(dn, "brcm,gisb-arb-master-mask", 455 &gdev->valid_mask)) 456 gdev->valid_mask = 0xffffffff; 457 458 /* Proceed with reading the litteral names if we agree on the 459 * number of masters 460 */ 461 num_masters = of_property_count_strings(dn, 462 "brcm,gisb-arb-master-names"); 463 if (hweight_long(gdev->valid_mask) == num_masters) { 464 first = ffs(gdev->valid_mask) - 1; 465 last = fls(gdev->valid_mask) - 1; 466 467 for (i = first; i < last; i++) { 468 if (!(gdev->valid_mask & BIT(i))) 469 continue; 470 471 of_property_read_string_index(dn, 472 "brcm,gisb-arb-master-names", j, 473 &gdev->master_names[i]); 474 j++; 475 } 476 } 477 478 err = sysfs_create_group(&pdev->dev.kobj, &gisb_arb_sysfs_attr_group); 479 if (err) 480 return err; 481 482 platform_set_drvdata(pdev, gdev); 483 484 list_add_tail(&gdev->next, &brcmstb_gisb_arb_device_list); 485 486#ifdef CONFIG_MIPS 487 board_be_handler = brcmstb_bus_error_handler; 488#endif 489 490 if (list_is_singular(&brcmstb_gisb_arb_device_list)) { 491 register_die_notifier(&gisb_die_notifier); 492 atomic_notifier_chain_register(&panic_notifier_list, 493 &gisb_panic_notifier); 494 } 495 496 dev_info(&pdev->dev, "registered irqs: %d, %d\n", 497 timeout_irq, tea_irq); 498 499 return 0; 500} 501 502#ifdef CONFIG_PM_SLEEP 503static int brcmstb_gisb_arb_suspend(struct device *dev) 504{ 505 struct brcmstb_gisb_arb_device *gdev = dev_get_drvdata(dev); 506 507 gdev->saved_timeout = gisb_read(gdev, ARB_TIMER); 508 509 return 0; 510} 511 512/* Make sure we provide the same timeout value that was configured before, and 513 * do this before the GISB timeout interrupt handler has any chance to run. 514 */ 515static int brcmstb_gisb_arb_resume_noirq(struct device *dev) 516{ 517 struct brcmstb_gisb_arb_device *gdev = dev_get_drvdata(dev); 518 519 gisb_write(gdev, gdev->saved_timeout, ARB_TIMER); 520 521 return 0; 522} 523#else 524#define brcmstb_gisb_arb_suspend NULL 525#define brcmstb_gisb_arb_resume_noirq NULL 526#endif 527 528static const struct dev_pm_ops brcmstb_gisb_arb_pm_ops = { 529 .suspend = brcmstb_gisb_arb_suspend, 530 .resume_noirq = brcmstb_gisb_arb_resume_noirq, 531}; 532 533static struct platform_driver brcmstb_gisb_arb_driver = { 534 .driver = { 535 .name = "brcm-gisb-arb", 536 .of_match_table = brcmstb_gisb_arb_of_match, 537 .pm = &brcmstb_gisb_arb_pm_ops, 538 }, 539}; 540 541static int __init brcm_gisb_driver_init(void) 542{ 543 return platform_driver_probe(&brcmstb_gisb_arb_driver, 544 brcmstb_gisb_arb_probe); 545} 546 547module_init(brcm_gisb_driver_init); 548