David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-only |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 2 | /* |
| 3 | * linux/arch/arm/common/amba.c |
| 4 | * |
| 5 | * Copyright (C) 2003 Deep Blue Solutions Ltd, All Rights Reserved. |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 6 | */ |
| 7 | #include <linux/module.h> |
| 8 | #include <linux/init.h> |
| 9 | #include <linux/device.h> |
| 10 | #include <linux/string.h> |
| 11 | #include <linux/slab.h> |
| 12 | #include <linux/io.h> |
| 13 | #include <linux/pm.h> |
| 14 | #include <linux/pm_runtime.h> |
| 15 | #include <linux/pm_domain.h> |
| 16 | #include <linux/amba/bus.h> |
| 17 | #include <linux/sizes.h> |
| 18 | #include <linux/limits.h> |
| 19 | #include <linux/clk/clk-conf.h> |
| 20 | #include <linux/platform_device.h> |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 21 | #include <linux/reset.h> |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 22 | |
| 23 | #include <asm/irq.h> |
| 24 | |
| 25 | #define to_amba_driver(d) container_of(d, struct amba_driver, drv) |
| 26 | |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 27 | /* called on periphid match and class 0x9 coresight device. */ |
| 28 | static int |
| 29 | amba_cs_uci_id_match(const struct amba_id *table, struct amba_device *dev) |
| 30 | { |
| 31 | int ret = 0; |
| 32 | struct amba_cs_uci_id *uci; |
| 33 | |
| 34 | uci = table->data; |
| 35 | |
| 36 | /* no table data or zero mask - return match on periphid */ |
| 37 | if (!uci || (uci->devarch_mask == 0)) |
| 38 | return 1; |
| 39 | |
| 40 | /* test against read devtype and masked devarch value */ |
| 41 | ret = (dev->uci.devtype == uci->devtype) && |
| 42 | ((dev->uci.devarch & uci->devarch_mask) == uci->devarch); |
| 43 | return ret; |
| 44 | } |
| 45 | |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 46 | static const struct amba_id * |
| 47 | amba_lookup(const struct amba_id *table, struct amba_device *dev) |
| 48 | { |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 49 | while (table->mask) { |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 50 | if (((dev->periphid & table->mask) == table->id) && |
| 51 | ((dev->cid != CORESIGHT_CID) || |
| 52 | (amba_cs_uci_id_match(table, dev)))) |
| 53 | return table; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 54 | table++; |
| 55 | } |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 56 | return NULL; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 57 | } |
| 58 | |
| 59 | static int amba_match(struct device *dev, struct device_driver *drv) |
| 60 | { |
| 61 | struct amba_device *pcdev = to_amba_device(dev); |
| 62 | struct amba_driver *pcdrv = to_amba_driver(drv); |
| 63 | |
| 64 | /* When driver_override is set, only bind to the matching driver */ |
| 65 | if (pcdev->driver_override) |
| 66 | return !strcmp(pcdev->driver_override, drv->name); |
| 67 | |
| 68 | return amba_lookup(pcdrv->id_table, pcdev) != NULL; |
| 69 | } |
| 70 | |
| 71 | static int amba_uevent(struct device *dev, struct kobj_uevent_env *env) |
| 72 | { |
| 73 | struct amba_device *pcdev = to_amba_device(dev); |
| 74 | int retval = 0; |
| 75 | |
| 76 | retval = add_uevent_var(env, "AMBA_ID=%08x", pcdev->periphid); |
| 77 | if (retval) |
| 78 | return retval; |
| 79 | |
| 80 | retval = add_uevent_var(env, "MODALIAS=amba:d%08X", pcdev->periphid); |
| 81 | return retval; |
| 82 | } |
| 83 | |
| 84 | static ssize_t driver_override_show(struct device *_dev, |
| 85 | struct device_attribute *attr, char *buf) |
| 86 | { |
| 87 | struct amba_device *dev = to_amba_device(_dev); |
| 88 | ssize_t len; |
| 89 | |
| 90 | device_lock(_dev); |
| 91 | len = sprintf(buf, "%s\n", dev->driver_override); |
| 92 | device_unlock(_dev); |
| 93 | return len; |
| 94 | } |
| 95 | |
| 96 | static ssize_t driver_override_store(struct device *_dev, |
| 97 | struct device_attribute *attr, |
| 98 | const char *buf, size_t count) |
| 99 | { |
| 100 | struct amba_device *dev = to_amba_device(_dev); |
| 101 | char *driver_override, *old, *cp; |
| 102 | |
| 103 | /* We need to keep extra room for a newline */ |
| 104 | if (count >= (PAGE_SIZE - 1)) |
| 105 | return -EINVAL; |
| 106 | |
| 107 | driver_override = kstrndup(buf, count, GFP_KERNEL); |
| 108 | if (!driver_override) |
| 109 | return -ENOMEM; |
| 110 | |
| 111 | cp = strchr(driver_override, '\n'); |
| 112 | if (cp) |
| 113 | *cp = '\0'; |
| 114 | |
| 115 | device_lock(_dev); |
| 116 | old = dev->driver_override; |
| 117 | if (strlen(driver_override)) { |
| 118 | dev->driver_override = driver_override; |
| 119 | } else { |
| 120 | kfree(driver_override); |
| 121 | dev->driver_override = NULL; |
| 122 | } |
| 123 | device_unlock(_dev); |
| 124 | |
| 125 | kfree(old); |
| 126 | |
| 127 | return count; |
| 128 | } |
| 129 | static DEVICE_ATTR_RW(driver_override); |
| 130 | |
| 131 | #define amba_attr_func(name,fmt,arg...) \ |
| 132 | static ssize_t name##_show(struct device *_dev, \ |
| 133 | struct device_attribute *attr, char *buf) \ |
| 134 | { \ |
| 135 | struct amba_device *dev = to_amba_device(_dev); \ |
| 136 | return sprintf(buf, fmt, arg); \ |
| 137 | } \ |
| 138 | static DEVICE_ATTR_RO(name) |
| 139 | |
| 140 | amba_attr_func(id, "%08x\n", dev->periphid); |
| 141 | amba_attr_func(irq0, "%u\n", dev->irq[0]); |
| 142 | amba_attr_func(irq1, "%u\n", dev->irq[1]); |
| 143 | amba_attr_func(resource, "\t%016llx\t%016llx\t%016lx\n", |
| 144 | (unsigned long long)dev->res.start, (unsigned long long)dev->res.end, |
| 145 | dev->res.flags); |
| 146 | |
| 147 | static struct attribute *amba_dev_attrs[] = { |
| 148 | &dev_attr_id.attr, |
| 149 | &dev_attr_resource.attr, |
| 150 | &dev_attr_driver_override.attr, |
| 151 | NULL, |
| 152 | }; |
| 153 | ATTRIBUTE_GROUPS(amba_dev); |
| 154 | |
| 155 | #ifdef CONFIG_PM |
| 156 | /* |
| 157 | * Hooks to provide runtime PM of the pclk (bus clock). It is safe to |
| 158 | * enable/disable the bus clock at runtime PM suspend/resume as this |
| 159 | * does not result in loss of context. |
| 160 | */ |
| 161 | static int amba_pm_runtime_suspend(struct device *dev) |
| 162 | { |
| 163 | struct amba_device *pcdev = to_amba_device(dev); |
| 164 | int ret = pm_generic_runtime_suspend(dev); |
| 165 | |
| 166 | if (ret == 0 && dev->driver) { |
| 167 | if (pm_runtime_is_irq_safe(dev)) |
| 168 | clk_disable(pcdev->pclk); |
| 169 | else |
| 170 | clk_disable_unprepare(pcdev->pclk); |
| 171 | } |
| 172 | |
| 173 | return ret; |
| 174 | } |
| 175 | |
| 176 | static int amba_pm_runtime_resume(struct device *dev) |
| 177 | { |
| 178 | struct amba_device *pcdev = to_amba_device(dev); |
| 179 | int ret; |
| 180 | |
| 181 | if (dev->driver) { |
| 182 | if (pm_runtime_is_irq_safe(dev)) |
| 183 | ret = clk_enable(pcdev->pclk); |
| 184 | else |
| 185 | ret = clk_prepare_enable(pcdev->pclk); |
| 186 | /* Failure is probably fatal to the system, but... */ |
| 187 | if (ret) |
| 188 | return ret; |
| 189 | } |
| 190 | |
| 191 | return pm_generic_runtime_resume(dev); |
| 192 | } |
| 193 | #endif /* CONFIG_PM */ |
| 194 | |
| 195 | static const struct dev_pm_ops amba_pm = { |
| 196 | .suspend = pm_generic_suspend, |
| 197 | .resume = pm_generic_resume, |
| 198 | .freeze = pm_generic_freeze, |
| 199 | .thaw = pm_generic_thaw, |
| 200 | .poweroff = pm_generic_poweroff, |
| 201 | .restore = pm_generic_restore, |
| 202 | SET_RUNTIME_PM_OPS( |
| 203 | amba_pm_runtime_suspend, |
| 204 | amba_pm_runtime_resume, |
| 205 | NULL |
| 206 | ) |
| 207 | }; |
| 208 | |
| 209 | /* |
| 210 | * Primecells are part of the Advanced Microcontroller Bus Architecture, |
| 211 | * so we call the bus "amba". |
| 212 | * DMA configuration for platform and AMBA bus is same. So here we reuse |
| 213 | * platform's DMA config routine. |
| 214 | */ |
| 215 | struct bus_type amba_bustype = { |
| 216 | .name = "amba", |
| 217 | .dev_groups = amba_dev_groups, |
| 218 | .match = amba_match, |
| 219 | .uevent = amba_uevent, |
| 220 | .dma_configure = platform_dma_configure, |
| 221 | .pm = &amba_pm, |
| 222 | }; |
| 223 | EXPORT_SYMBOL_GPL(amba_bustype); |
| 224 | |
| 225 | static int __init amba_init(void) |
| 226 | { |
| 227 | return bus_register(&amba_bustype); |
| 228 | } |
| 229 | |
| 230 | postcore_initcall(amba_init); |
| 231 | |
| 232 | static int amba_get_enable_pclk(struct amba_device *pcdev) |
| 233 | { |
| 234 | int ret; |
| 235 | |
| 236 | pcdev->pclk = clk_get(&pcdev->dev, "apb_pclk"); |
| 237 | if (IS_ERR(pcdev->pclk)) |
| 238 | return PTR_ERR(pcdev->pclk); |
| 239 | |
| 240 | ret = clk_prepare_enable(pcdev->pclk); |
| 241 | if (ret) |
| 242 | clk_put(pcdev->pclk); |
| 243 | |
| 244 | return ret; |
| 245 | } |
| 246 | |
| 247 | static void amba_put_disable_pclk(struct amba_device *pcdev) |
| 248 | { |
| 249 | clk_disable_unprepare(pcdev->pclk); |
| 250 | clk_put(pcdev->pclk); |
| 251 | } |
| 252 | |
| 253 | /* |
| 254 | * These are the device model conversion veneers; they convert the |
| 255 | * device model structures to our more specific structures. |
| 256 | */ |
| 257 | static int amba_probe(struct device *dev) |
| 258 | { |
| 259 | struct amba_device *pcdev = to_amba_device(dev); |
| 260 | struct amba_driver *pcdrv = to_amba_driver(dev->driver); |
| 261 | const struct amba_id *id = amba_lookup(pcdrv->id_table, pcdev); |
| 262 | int ret; |
| 263 | |
| 264 | do { |
| 265 | ret = of_clk_set_defaults(dev->of_node, false); |
| 266 | if (ret < 0) |
| 267 | break; |
| 268 | |
| 269 | ret = dev_pm_domain_attach(dev, true); |
| 270 | if (ret) |
| 271 | break; |
| 272 | |
| 273 | ret = amba_get_enable_pclk(pcdev); |
| 274 | if (ret) { |
| 275 | dev_pm_domain_detach(dev, true); |
| 276 | break; |
| 277 | } |
| 278 | |
| 279 | pm_runtime_get_noresume(dev); |
| 280 | pm_runtime_set_active(dev); |
| 281 | pm_runtime_enable(dev); |
| 282 | |
| 283 | ret = pcdrv->probe(pcdev, id); |
| 284 | if (ret == 0) |
| 285 | break; |
| 286 | |
| 287 | pm_runtime_disable(dev); |
| 288 | pm_runtime_set_suspended(dev); |
| 289 | pm_runtime_put_noidle(dev); |
| 290 | |
| 291 | amba_put_disable_pclk(pcdev); |
| 292 | dev_pm_domain_detach(dev, true); |
| 293 | } while (0); |
| 294 | |
| 295 | return ret; |
| 296 | } |
| 297 | |
| 298 | static int amba_remove(struct device *dev) |
| 299 | { |
| 300 | struct amba_device *pcdev = to_amba_device(dev); |
| 301 | struct amba_driver *drv = to_amba_driver(dev->driver); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 302 | |
| 303 | pm_runtime_get_sync(dev); |
Olivier Deprez | 0e64123 | 2021-09-23 10:07:05 +0200 | [diff] [blame] | 304 | if (drv->remove) |
Olivier Deprez | 92d4c21 | 2022-12-06 15:05:30 +0100 | [diff] [blame] | 305 | drv->remove(pcdev); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 306 | pm_runtime_put_noidle(dev); |
| 307 | |
| 308 | /* Undo the runtime PM settings in amba_probe() */ |
| 309 | pm_runtime_disable(dev); |
| 310 | pm_runtime_set_suspended(dev); |
| 311 | pm_runtime_put_noidle(dev); |
| 312 | |
| 313 | amba_put_disable_pclk(pcdev); |
| 314 | dev_pm_domain_detach(dev, true); |
| 315 | |
Olivier Deprez | 92d4c21 | 2022-12-06 15:05:30 +0100 | [diff] [blame] | 316 | return 0; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 317 | } |
| 318 | |
| 319 | static void amba_shutdown(struct device *dev) |
| 320 | { |
| 321 | struct amba_driver *drv = to_amba_driver(dev->driver); |
Olivier Deprez | 0e64123 | 2021-09-23 10:07:05 +0200 | [diff] [blame] | 322 | |
| 323 | if (drv->shutdown) |
| 324 | drv->shutdown(to_amba_device(dev)); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 325 | } |
| 326 | |
| 327 | /** |
| 328 | * amba_driver_register - register an AMBA device driver |
| 329 | * @drv: amba device driver structure |
| 330 | * |
| 331 | * Register an AMBA device driver with the Linux device model |
| 332 | * core. If devices pre-exist, the drivers probe function will |
| 333 | * be called. |
| 334 | */ |
| 335 | int amba_driver_register(struct amba_driver *drv) |
| 336 | { |
Olivier Deprez | 0e64123 | 2021-09-23 10:07:05 +0200 | [diff] [blame] | 337 | if (!drv->probe) |
| 338 | return -EINVAL; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 339 | |
Olivier Deprez | 0e64123 | 2021-09-23 10:07:05 +0200 | [diff] [blame] | 340 | drv->drv.bus = &amba_bustype; |
| 341 | drv->drv.probe = amba_probe; |
| 342 | drv->drv.remove = amba_remove; |
| 343 | drv->drv.shutdown = amba_shutdown; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 344 | |
| 345 | return driver_register(&drv->drv); |
| 346 | } |
| 347 | |
| 348 | /** |
| 349 | * amba_driver_unregister - remove an AMBA device driver |
| 350 | * @drv: AMBA device driver structure to remove |
| 351 | * |
| 352 | * Unregister an AMBA device driver from the Linux device |
| 353 | * model. The device model will call the drivers remove function |
| 354 | * for each device the device driver is currently handling. |
| 355 | */ |
| 356 | void amba_driver_unregister(struct amba_driver *drv) |
| 357 | { |
| 358 | driver_unregister(&drv->drv); |
| 359 | } |
| 360 | |
| 361 | |
| 362 | static void amba_device_release(struct device *dev) |
| 363 | { |
| 364 | struct amba_device *d = to_amba_device(dev); |
| 365 | |
| 366 | if (d->res.parent) |
| 367 | release_resource(&d->res); |
| 368 | kfree(d); |
| 369 | } |
| 370 | |
| 371 | static int amba_device_try_add(struct amba_device *dev, struct resource *parent) |
| 372 | { |
| 373 | u32 size; |
| 374 | void __iomem *tmp; |
| 375 | int i, ret; |
| 376 | |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 377 | ret = request_resource(parent, &dev->res); |
| 378 | if (ret) |
| 379 | goto err_out; |
| 380 | |
| 381 | /* Hard-coded primecell ID instead of plug-n-play */ |
| 382 | if (dev->periphid != 0) |
| 383 | goto skip_probe; |
| 384 | |
| 385 | /* |
| 386 | * Dynamically calculate the size of the resource |
| 387 | * and use this for iomap |
| 388 | */ |
| 389 | size = resource_size(&dev->res); |
| 390 | tmp = ioremap(dev->res.start, size); |
| 391 | if (!tmp) { |
| 392 | ret = -ENOMEM; |
| 393 | goto err_release; |
| 394 | } |
| 395 | |
| 396 | ret = dev_pm_domain_attach(&dev->dev, true); |
| 397 | if (ret) { |
| 398 | iounmap(tmp); |
| 399 | goto err_release; |
| 400 | } |
| 401 | |
| 402 | ret = amba_get_enable_pclk(dev); |
| 403 | if (ret == 0) { |
| 404 | u32 pid, cid; |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 405 | struct reset_control *rstc; |
| 406 | |
| 407 | /* |
| 408 | * Find reset control(s) of the amba bus and de-assert them. |
| 409 | */ |
| 410 | rstc = of_reset_control_array_get_optional_shared(dev->dev.of_node); |
| 411 | if (IS_ERR(rstc)) { |
| 412 | ret = PTR_ERR(rstc); |
| 413 | if (ret != -EPROBE_DEFER) |
| 414 | dev_err(&dev->dev, "can't get reset: %d\n", |
| 415 | ret); |
| 416 | goto err_reset; |
| 417 | } |
| 418 | reset_control_deassert(rstc); |
| 419 | reset_control_put(rstc); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 420 | |
| 421 | /* |
| 422 | * Read pid and cid based on size of resource |
| 423 | * they are located at end of region |
| 424 | */ |
| 425 | for (pid = 0, i = 0; i < 4; i++) |
| 426 | pid |= (readl(tmp + size - 0x20 + 4 * i) & 255) << |
| 427 | (i * 8); |
| 428 | for (cid = 0, i = 0; i < 4; i++) |
| 429 | cid |= (readl(tmp + size - 0x10 + 4 * i) & 255) << |
| 430 | (i * 8); |
| 431 | |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 432 | if (cid == CORESIGHT_CID) { |
| 433 | /* set the base to the start of the last 4k block */ |
| 434 | void __iomem *csbase = tmp + size - 4096; |
| 435 | |
| 436 | dev->uci.devarch = |
| 437 | readl(csbase + UCI_REG_DEVARCH_OFFSET); |
| 438 | dev->uci.devtype = |
| 439 | readl(csbase + UCI_REG_DEVTYPE_OFFSET) & 0xff; |
| 440 | } |
| 441 | |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 442 | amba_put_disable_pclk(dev); |
| 443 | |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 444 | if (cid == AMBA_CID || cid == CORESIGHT_CID) { |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 445 | dev->periphid = pid; |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 446 | dev->cid = cid; |
| 447 | } |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 448 | |
| 449 | if (!dev->periphid) |
| 450 | ret = -ENODEV; |
| 451 | } |
| 452 | |
| 453 | iounmap(tmp); |
| 454 | dev_pm_domain_detach(&dev->dev, true); |
| 455 | |
| 456 | if (ret) |
| 457 | goto err_release; |
| 458 | |
| 459 | skip_probe: |
| 460 | ret = device_add(&dev->dev); |
| 461 | if (ret) |
| 462 | goto err_release; |
| 463 | |
| 464 | if (dev->irq[0]) |
| 465 | ret = device_create_file(&dev->dev, &dev_attr_irq0); |
| 466 | if (ret == 0 && dev->irq[1]) |
| 467 | ret = device_create_file(&dev->dev, &dev_attr_irq1); |
| 468 | if (ret == 0) |
| 469 | return ret; |
| 470 | |
| 471 | device_unregister(&dev->dev); |
| 472 | |
| 473 | err_release: |
| 474 | release_resource(&dev->res); |
| 475 | err_out: |
| 476 | return ret; |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 477 | |
| 478 | err_reset: |
| 479 | amba_put_disable_pclk(dev); |
| 480 | iounmap(tmp); |
| 481 | dev_pm_domain_detach(&dev->dev, true); |
| 482 | goto err_release; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 483 | } |
| 484 | |
| 485 | /* |
| 486 | * Registration of AMBA device require reading its pid and cid registers. |
| 487 | * To do this, the device must be turned on (if it is a part of power domain) |
| 488 | * and have clocks enabled. However in some cases those resources might not be |
| 489 | * yet available. Returning EPROBE_DEFER is not a solution in such case, |
| 490 | * because callers don't handle this special error code. Instead such devices |
| 491 | * are added to the special list and their registration is retried from |
| 492 | * periodic worker, until all resources are available and registration succeeds. |
| 493 | */ |
| 494 | struct deferred_device { |
| 495 | struct amba_device *dev; |
| 496 | struct resource *parent; |
| 497 | struct list_head node; |
| 498 | }; |
| 499 | |
| 500 | static LIST_HEAD(deferred_devices); |
| 501 | static DEFINE_MUTEX(deferred_devices_lock); |
| 502 | |
| 503 | static void amba_deferred_retry_func(struct work_struct *dummy); |
| 504 | static DECLARE_DELAYED_WORK(deferred_retry_work, amba_deferred_retry_func); |
| 505 | |
| 506 | #define DEFERRED_DEVICE_TIMEOUT (msecs_to_jiffies(5 * 1000)) |
| 507 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame] | 508 | static int amba_deferred_retry(void) |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 509 | { |
| 510 | struct deferred_device *ddev, *tmp; |
| 511 | |
| 512 | mutex_lock(&deferred_devices_lock); |
| 513 | |
| 514 | list_for_each_entry_safe(ddev, tmp, &deferred_devices, node) { |
| 515 | int ret = amba_device_try_add(ddev->dev, ddev->parent); |
| 516 | |
| 517 | if (ret == -EPROBE_DEFER) |
| 518 | continue; |
| 519 | |
| 520 | list_del_init(&ddev->node); |
| 521 | kfree(ddev); |
| 522 | } |
| 523 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame] | 524 | mutex_unlock(&deferred_devices_lock); |
| 525 | |
| 526 | return 0; |
| 527 | } |
| 528 | late_initcall(amba_deferred_retry); |
| 529 | |
| 530 | static void amba_deferred_retry_func(struct work_struct *dummy) |
| 531 | { |
| 532 | amba_deferred_retry(); |
| 533 | |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 534 | if (!list_empty(&deferred_devices)) |
| 535 | schedule_delayed_work(&deferred_retry_work, |
| 536 | DEFERRED_DEVICE_TIMEOUT); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 537 | } |
| 538 | |
| 539 | /** |
| 540 | * amba_device_add - add a previously allocated AMBA device structure |
| 541 | * @dev: AMBA device allocated by amba_device_alloc |
| 542 | * @parent: resource parent for this devices resources |
| 543 | * |
| 544 | * Claim the resource, and read the device cell ID if not already |
| 545 | * initialized. Register the AMBA device with the Linux device |
| 546 | * manager. |
| 547 | */ |
| 548 | int amba_device_add(struct amba_device *dev, struct resource *parent) |
| 549 | { |
| 550 | int ret = amba_device_try_add(dev, parent); |
| 551 | |
| 552 | if (ret == -EPROBE_DEFER) { |
| 553 | struct deferred_device *ddev; |
| 554 | |
| 555 | ddev = kmalloc(sizeof(*ddev), GFP_KERNEL); |
| 556 | if (!ddev) |
| 557 | return -ENOMEM; |
| 558 | |
| 559 | ddev->dev = dev; |
| 560 | ddev->parent = parent; |
| 561 | ret = 0; |
| 562 | |
| 563 | mutex_lock(&deferred_devices_lock); |
| 564 | |
| 565 | if (list_empty(&deferred_devices)) |
| 566 | schedule_delayed_work(&deferred_retry_work, |
| 567 | DEFERRED_DEVICE_TIMEOUT); |
| 568 | list_add_tail(&ddev->node, &deferred_devices); |
| 569 | |
| 570 | mutex_unlock(&deferred_devices_lock); |
| 571 | } |
| 572 | return ret; |
| 573 | } |
| 574 | EXPORT_SYMBOL_GPL(amba_device_add); |
| 575 | |
| 576 | static struct amba_device * |
| 577 | amba_aphb_device_add(struct device *parent, const char *name, |
| 578 | resource_size_t base, size_t size, int irq1, int irq2, |
| 579 | void *pdata, unsigned int periphid, u64 dma_mask, |
| 580 | struct resource *resbase) |
| 581 | { |
| 582 | struct amba_device *dev; |
| 583 | int ret; |
| 584 | |
| 585 | dev = amba_device_alloc(name, base, size); |
| 586 | if (!dev) |
| 587 | return ERR_PTR(-ENOMEM); |
| 588 | |
| 589 | dev->dev.coherent_dma_mask = dma_mask; |
| 590 | dev->irq[0] = irq1; |
| 591 | dev->irq[1] = irq2; |
| 592 | dev->periphid = periphid; |
| 593 | dev->dev.platform_data = pdata; |
| 594 | dev->dev.parent = parent; |
| 595 | |
| 596 | ret = amba_device_add(dev, resbase); |
| 597 | if (ret) { |
| 598 | amba_device_put(dev); |
| 599 | return ERR_PTR(ret); |
| 600 | } |
| 601 | |
| 602 | return dev; |
| 603 | } |
| 604 | |
| 605 | struct amba_device * |
| 606 | amba_apb_device_add(struct device *parent, const char *name, |
| 607 | resource_size_t base, size_t size, int irq1, int irq2, |
| 608 | void *pdata, unsigned int periphid) |
| 609 | { |
| 610 | return amba_aphb_device_add(parent, name, base, size, irq1, irq2, pdata, |
| 611 | periphid, 0, &iomem_resource); |
| 612 | } |
| 613 | EXPORT_SYMBOL_GPL(amba_apb_device_add); |
| 614 | |
| 615 | struct amba_device * |
| 616 | amba_ahb_device_add(struct device *parent, const char *name, |
| 617 | resource_size_t base, size_t size, int irq1, int irq2, |
| 618 | void *pdata, unsigned int periphid) |
| 619 | { |
| 620 | return amba_aphb_device_add(parent, name, base, size, irq1, irq2, pdata, |
| 621 | periphid, ~0ULL, &iomem_resource); |
| 622 | } |
| 623 | EXPORT_SYMBOL_GPL(amba_ahb_device_add); |
| 624 | |
| 625 | struct amba_device * |
| 626 | amba_apb_device_add_res(struct device *parent, const char *name, |
| 627 | resource_size_t base, size_t size, int irq1, |
| 628 | int irq2, void *pdata, unsigned int periphid, |
| 629 | struct resource *resbase) |
| 630 | { |
| 631 | return amba_aphb_device_add(parent, name, base, size, irq1, irq2, pdata, |
| 632 | periphid, 0, resbase); |
| 633 | } |
| 634 | EXPORT_SYMBOL_GPL(amba_apb_device_add_res); |
| 635 | |
| 636 | struct amba_device * |
| 637 | amba_ahb_device_add_res(struct device *parent, const char *name, |
| 638 | resource_size_t base, size_t size, int irq1, |
| 639 | int irq2, void *pdata, unsigned int periphid, |
| 640 | struct resource *resbase) |
| 641 | { |
| 642 | return amba_aphb_device_add(parent, name, base, size, irq1, irq2, pdata, |
| 643 | periphid, ~0ULL, resbase); |
| 644 | } |
| 645 | EXPORT_SYMBOL_GPL(amba_ahb_device_add_res); |
| 646 | |
| 647 | |
| 648 | static void amba_device_initialize(struct amba_device *dev, const char *name) |
| 649 | { |
| 650 | device_initialize(&dev->dev); |
| 651 | if (name) |
| 652 | dev_set_name(&dev->dev, "%s", name); |
| 653 | dev->dev.release = amba_device_release; |
| 654 | dev->dev.bus = &amba_bustype; |
| 655 | dev->dev.dma_mask = &dev->dev.coherent_dma_mask; |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame] | 656 | dev->dev.dma_parms = &dev->dma_parms; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 657 | dev->res.name = dev_name(&dev->dev); |
| 658 | } |
| 659 | |
| 660 | /** |
| 661 | * amba_device_alloc - allocate an AMBA device |
| 662 | * @name: sysfs name of the AMBA device |
| 663 | * @base: base of AMBA device |
| 664 | * @size: size of AMBA device |
| 665 | * |
| 666 | * Allocate and initialize an AMBA device structure. Returns %NULL |
| 667 | * on failure. |
| 668 | */ |
| 669 | struct amba_device *amba_device_alloc(const char *name, resource_size_t base, |
| 670 | size_t size) |
| 671 | { |
| 672 | struct amba_device *dev; |
| 673 | |
| 674 | dev = kzalloc(sizeof(*dev), GFP_KERNEL); |
| 675 | if (dev) { |
| 676 | amba_device_initialize(dev, name); |
| 677 | dev->res.start = base; |
| 678 | dev->res.end = base + size - 1; |
| 679 | dev->res.flags = IORESOURCE_MEM; |
| 680 | } |
| 681 | |
| 682 | return dev; |
| 683 | } |
| 684 | EXPORT_SYMBOL_GPL(amba_device_alloc); |
| 685 | |
| 686 | /** |
| 687 | * amba_device_register - register an AMBA device |
| 688 | * @dev: AMBA device to register |
| 689 | * @parent: parent memory resource |
| 690 | * |
| 691 | * Setup the AMBA device, reading the cell ID if present. |
| 692 | * Claim the resource, and register the AMBA device with |
| 693 | * the Linux device manager. |
| 694 | */ |
| 695 | int amba_device_register(struct amba_device *dev, struct resource *parent) |
| 696 | { |
| 697 | amba_device_initialize(dev, dev->dev.init_name); |
| 698 | dev->dev.init_name = NULL; |
| 699 | |
| 700 | return amba_device_add(dev, parent); |
| 701 | } |
| 702 | |
| 703 | /** |
| 704 | * amba_device_put - put an AMBA device |
| 705 | * @dev: AMBA device to put |
| 706 | */ |
| 707 | void amba_device_put(struct amba_device *dev) |
| 708 | { |
| 709 | put_device(&dev->dev); |
| 710 | } |
| 711 | EXPORT_SYMBOL_GPL(amba_device_put); |
| 712 | |
| 713 | /** |
| 714 | * amba_device_unregister - unregister an AMBA device |
| 715 | * @dev: AMBA device to remove |
| 716 | * |
| 717 | * Remove the specified AMBA device from the Linux device |
| 718 | * manager. All files associated with this object will be |
| 719 | * destroyed, and device drivers notified that the device has |
| 720 | * been removed. The AMBA device's resources including |
| 721 | * the amba_device structure will be freed once all |
| 722 | * references to it have been dropped. |
| 723 | */ |
| 724 | void amba_device_unregister(struct amba_device *dev) |
| 725 | { |
| 726 | device_unregister(&dev->dev); |
| 727 | } |
| 728 | |
| 729 | |
| 730 | struct find_data { |
| 731 | struct amba_device *dev; |
| 732 | struct device *parent; |
| 733 | const char *busid; |
| 734 | unsigned int id; |
| 735 | unsigned int mask; |
| 736 | }; |
| 737 | |
| 738 | static int amba_find_match(struct device *dev, void *data) |
| 739 | { |
| 740 | struct find_data *d = data; |
| 741 | struct amba_device *pcdev = to_amba_device(dev); |
| 742 | int r; |
| 743 | |
| 744 | r = (pcdev->periphid & d->mask) == d->id; |
| 745 | if (d->parent) |
| 746 | r &= d->parent == dev->parent; |
| 747 | if (d->busid) |
| 748 | r &= strcmp(dev_name(dev), d->busid) == 0; |
| 749 | |
| 750 | if (r) { |
| 751 | get_device(dev); |
| 752 | d->dev = pcdev; |
| 753 | } |
| 754 | |
| 755 | return r; |
| 756 | } |
| 757 | |
| 758 | /** |
| 759 | * amba_find_device - locate an AMBA device given a bus id |
| 760 | * @busid: bus id for device (or NULL) |
| 761 | * @parent: parent device (or NULL) |
| 762 | * @id: peripheral ID (or 0) |
| 763 | * @mask: peripheral ID mask (or 0) |
| 764 | * |
| 765 | * Return the AMBA device corresponding to the supplied parameters. |
| 766 | * If no device matches, returns NULL. |
| 767 | * |
| 768 | * NOTE: When a valid device is found, its refcount is |
| 769 | * incremented, and must be decremented before the returned |
| 770 | * reference. |
| 771 | */ |
| 772 | struct amba_device * |
| 773 | amba_find_device(const char *busid, struct device *parent, unsigned int id, |
| 774 | unsigned int mask) |
| 775 | { |
| 776 | struct find_data data; |
| 777 | |
| 778 | data.dev = NULL; |
| 779 | data.parent = parent; |
| 780 | data.busid = busid; |
| 781 | data.id = id; |
| 782 | data.mask = mask; |
| 783 | |
| 784 | bus_for_each_dev(&amba_bustype, NULL, &data, amba_find_match); |
| 785 | |
| 786 | return data.dev; |
| 787 | } |
| 788 | |
| 789 | /** |
| 790 | * amba_request_regions - request all mem regions associated with device |
| 791 | * @dev: amba_device structure for device |
| 792 | * @name: name, or NULL to use driver name |
| 793 | */ |
| 794 | int amba_request_regions(struct amba_device *dev, const char *name) |
| 795 | { |
| 796 | int ret = 0; |
| 797 | u32 size; |
| 798 | |
| 799 | if (!name) |
| 800 | name = dev->dev.driver->name; |
| 801 | |
| 802 | size = resource_size(&dev->res); |
| 803 | |
| 804 | if (!request_mem_region(dev->res.start, size, name)) |
| 805 | ret = -EBUSY; |
| 806 | |
| 807 | return ret; |
| 808 | } |
| 809 | |
| 810 | /** |
| 811 | * amba_release_regions - release mem regions associated with device |
| 812 | * @dev: amba_device structure for device |
| 813 | * |
| 814 | * Release regions claimed by a successful call to amba_request_regions. |
| 815 | */ |
| 816 | void amba_release_regions(struct amba_device *dev) |
| 817 | { |
| 818 | u32 size; |
| 819 | |
| 820 | size = resource_size(&dev->res); |
| 821 | release_mem_region(dev->res.start, size); |
| 822 | } |
| 823 | |
| 824 | EXPORT_SYMBOL(amba_driver_register); |
| 825 | EXPORT_SYMBOL(amba_driver_unregister); |
| 826 | EXPORT_SYMBOL(amba_device_register); |
| 827 | EXPORT_SYMBOL(amba_device_unregister); |
| 828 | EXPORT_SYMBOL(amba_find_device); |
| 829 | EXPORT_SYMBOL(amba_request_regions); |
| 830 | EXPORT_SYMBOL(amba_release_regions); |