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