1/* 2 * Copyright �� 2012-2014 Intel Corporation 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the next 12 * paragraph) shall be included in all copies or substantial portions of the 13 * Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 21 * IN THE SOFTWARE. 22 * 23 * Authors: 24 * Eugeni Dodonov <eugeni.dodonov@intel.com> 25 * Daniel Vetter <daniel.vetter@ffwll.ch> 26 * 27 */ 28 29#include <linux/pm_runtime.h> 30 31#include <drm/drm_print.h> 32 33#include "i915_drv.h" 34#include "i915_trace.h" 35 36/** 37 * DOC: runtime pm 38 * 39 * The i915 driver supports dynamic enabling and disabling of entire hardware 40 * blocks at runtime. This is especially important on the display side where 41 * software is supposed to control many power gates manually on recent hardware, 42 * since on the GT side a lot of the power management is done by the hardware. 43 * But even there some manual control at the device level is required. 44 * 45 * Since i915 supports a diverse set of platforms with a unified codebase and 46 * hardware engineers just love to shuffle functionality around between power 47 * domains there's a sizeable amount of indirection required. This file provides 48 * generic functions to the driver for grabbing and releasing references for 49 * abstract power domains. It then maps those to the actual power wells 50 * present for a given platform. 51 */ 52 53static struct drm_i915_private *rpm_to_i915(struct intel_runtime_pm *rpm) 54{ 55 return container_of(rpm, struct drm_i915_private, runtime_pm); 56} 57 58#if IS_ENABLED(CONFIG_DRM_I915_DEBUG_RUNTIME_PM) 59 60static void init_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm) 61{ 62 ref_tracker_dir_init(&rpm->debug, INTEL_REFTRACK_DEAD_COUNT, dev_name(rpm->kdev)); 63} 64 65static intel_wakeref_t 66track_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm) 67{ 68 if (!rpm->available || rpm->no_wakeref_tracking) 69 return -1; 70 71 return intel_ref_tracker_alloc(&rpm->debug); 72} 73 74static void untrack_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm, 75 intel_wakeref_t wakeref) 76{ 77 if (!rpm->available || rpm->no_wakeref_tracking) 78 return; 79 80 intel_ref_tracker_free(&rpm->debug, wakeref); 81} 82 83static void untrack_all_intel_runtime_pm_wakerefs(struct intel_runtime_pm *rpm) 84{ 85 ref_tracker_dir_exit(&rpm->debug); 86} 87 88static noinline void 89__intel_wakeref_dec_and_check_tracking(struct intel_runtime_pm *rpm) 90{ 91 unsigned long flags; 92 93 if (!atomic_dec_and_lock_irqsave(&rpm->wakeref_count, 94 &rpm->debug.lock, 95 flags)) 96 return; 97 98 ref_tracker_dir_print_locked(&rpm->debug, INTEL_REFTRACK_PRINT_LIMIT); 99 spin_unlock_irqrestore(&rpm->debug.lock, flags); 100} 101 102void print_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm, 103 struct drm_printer *p) 104{ 105 intel_ref_tracker_show(&rpm->debug, p); 106} 107 108#else 109 110static void init_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm) 111{ 112} 113 114static intel_wakeref_t 115track_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm) 116{ 117 return -1; 118} 119 120static void untrack_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm, 121 intel_wakeref_t wakeref) 122{ 123} 124 125static void 126__intel_wakeref_dec_and_check_tracking(struct intel_runtime_pm *rpm) 127{ 128 atomic_dec(&rpm->wakeref_count); 129} 130 131static void 132untrack_all_intel_runtime_pm_wakerefs(struct intel_runtime_pm *rpm) 133{ 134} 135 136#endif 137 138static void 139intel_runtime_pm_acquire(struct intel_runtime_pm *rpm, bool wakelock) 140{ 141 if (wakelock) { 142 atomic_add(1 + INTEL_RPM_WAKELOCK_BIAS, &rpm->wakeref_count); 143 assert_rpm_wakelock_held(rpm); 144 } else { 145 atomic_inc(&rpm->wakeref_count); 146 assert_rpm_raw_wakeref_held(rpm); 147 } 148} 149 150static void 151intel_runtime_pm_release(struct intel_runtime_pm *rpm, int wakelock) 152{ 153 if (wakelock) { 154 assert_rpm_wakelock_held(rpm); 155 atomic_sub(INTEL_RPM_WAKELOCK_BIAS, &rpm->wakeref_count); 156 } else { 157 assert_rpm_raw_wakeref_held(rpm); 158 } 159 160 __intel_wakeref_dec_and_check_tracking(rpm); 161} 162 163static intel_wakeref_t __intel_runtime_pm_get(struct intel_runtime_pm *rpm, 164 bool wakelock) 165{ 166 struct drm_i915_private *i915 = rpm_to_i915(rpm); 167 int ret; 168 169 ret = pm_runtime_get_sync(rpm->kdev); 170 drm_WARN_ONCE(&i915->drm, ret < 0, 171 "pm_runtime_get_sync() failed: %d\n", ret); 172 173 intel_runtime_pm_acquire(rpm, wakelock); 174 175 return track_intel_runtime_pm_wakeref(rpm); 176} 177 178/** 179 * intel_runtime_pm_get_raw - grab a raw runtime pm reference 180 * @rpm: the intel_runtime_pm structure 181 * 182 * This is the unlocked version of intel_display_power_is_enabled() and should 183 * only be used from error capture and recovery code where deadlocks are 184 * possible. 185 * This function grabs a device-level runtime pm reference (mostly used for 186 * asynchronous PM management from display code) and ensures that it is powered 187 * up. Raw references are not considered during wakelock assert checks. 188 * 189 * Any runtime pm reference obtained by this function must have a symmetric 190 * call to intel_runtime_pm_put_raw() to release the reference again. 191 * 192 * Returns: the wakeref cookie to pass to intel_runtime_pm_put_raw(), evaluates 193 * as True if the wakeref was acquired, or False otherwise. 194 */ 195intel_wakeref_t intel_runtime_pm_get_raw(struct intel_runtime_pm *rpm) 196{ 197 return __intel_runtime_pm_get(rpm, false); 198} 199 200/** 201 * intel_runtime_pm_get - grab a runtime pm reference 202 * @rpm: the intel_runtime_pm structure 203 * 204 * This function grabs a device-level runtime pm reference (mostly used for GEM 205 * code to ensure the GTT or GT is on) and ensures that it is powered up. 206 * 207 * Any runtime pm reference obtained by this function must have a symmetric 208 * call to intel_runtime_pm_put() to release the reference again. 209 * 210 * Returns: the wakeref cookie to pass to intel_runtime_pm_put() 211 */ 212intel_wakeref_t intel_runtime_pm_get(struct intel_runtime_pm *rpm) 213{ 214 return __intel_runtime_pm_get(rpm, true); 215} 216 217/** 218 * __intel_runtime_pm_get_if_active - grab a runtime pm reference if device is active 219 * @rpm: the intel_runtime_pm structure 220 * @ignore_usecount: get a ref even if dev->power.usage_count is 0 221 * 222 * This function grabs a device-level runtime pm reference if the device is 223 * already active and ensures that it is powered up. It is illegal to try 224 * and access the HW should intel_runtime_pm_get_if_active() report failure. 225 * 226 * If @ignore_usecount is true, a reference will be acquired even if there is no 227 * user requiring the device to be powered up (dev->power.usage_count == 0). 228 * If the function returns false in this case then it's guaranteed that the 229 * device's runtime suspend hook has been called already or that it will be 230 * called (and hence it's also guaranteed that the device's runtime resume 231 * hook will be called eventually). 232 * 233 * Any runtime pm reference obtained by this function must have a symmetric 234 * call to intel_runtime_pm_put() to release the reference again. 235 * 236 * Returns: the wakeref cookie to pass to intel_runtime_pm_put(), evaluates 237 * as True if the wakeref was acquired, or False otherwise. 238 */ 239static intel_wakeref_t __intel_runtime_pm_get_if_active(struct intel_runtime_pm *rpm, 240 bool ignore_usecount) 241{ 242 if (IS_ENABLED(CONFIG_PM)) { 243 /* 244 * In cases runtime PM is disabled by the RPM core and we get 245 * an -EINVAL return value we are not supposed to call this 246 * function, since the power state is undefined. This applies 247 * atm to the late/early system suspend/resume handlers. 248 */ 249 if ((ignore_usecount && 250 pm_runtime_get_if_active(rpm->kdev) <= 0) || 251 (!ignore_usecount && 252 pm_runtime_get_if_in_use(rpm->kdev) <= 0)) 253 return 0; 254 } 255 256 intel_runtime_pm_acquire(rpm, true); 257 258 return track_intel_runtime_pm_wakeref(rpm); 259} 260 261intel_wakeref_t intel_runtime_pm_get_if_in_use(struct intel_runtime_pm *rpm) 262{ 263 return __intel_runtime_pm_get_if_active(rpm, false); 264} 265 266intel_wakeref_t intel_runtime_pm_get_if_active(struct intel_runtime_pm *rpm) 267{ 268 return __intel_runtime_pm_get_if_active(rpm, true); 269} 270 271/** 272 * intel_runtime_pm_get_noresume - grab a runtime pm reference 273 * @rpm: the intel_runtime_pm structure 274 * 275 * This function grabs a device-level runtime pm reference. 276 * 277 * It will _not_ resume the device but instead only get an extra wakeref. 278 * Therefore it is only valid to call this functions from contexts where 279 * the device is known to be active and with another wakeref previously hold. 280 * 281 * Any runtime pm reference obtained by this function must have a symmetric 282 * call to intel_runtime_pm_put() to release the reference again. 283 * 284 * Returns: the wakeref cookie to pass to intel_runtime_pm_put() 285 */ 286intel_wakeref_t intel_runtime_pm_get_noresume(struct intel_runtime_pm *rpm) 287{ 288 assert_rpm_raw_wakeref_held(rpm); 289 pm_runtime_get_noresume(rpm->kdev); 290 291 intel_runtime_pm_acquire(rpm, true); 292 293 return track_intel_runtime_pm_wakeref(rpm); 294} 295 296static void __intel_runtime_pm_put(struct intel_runtime_pm *rpm, 297 intel_wakeref_t wref, 298 bool wakelock) 299{ 300 struct device *kdev = rpm->kdev; 301 302 untrack_intel_runtime_pm_wakeref(rpm, wref); 303 304 intel_runtime_pm_release(rpm, wakelock); 305 306 pm_runtime_mark_last_busy(kdev); 307 pm_runtime_put_autosuspend(kdev); 308} 309 310/** 311 * intel_runtime_pm_put_raw - release a raw runtime pm reference 312 * @rpm: the intel_runtime_pm structure 313 * @wref: wakeref acquired for the reference that is being released 314 * 315 * This function drops the device-level runtime pm reference obtained by 316 * intel_runtime_pm_get_raw() and might power down the corresponding 317 * hardware block right away if this is the last reference. 318 */ 319void 320intel_runtime_pm_put_raw(struct intel_runtime_pm *rpm, intel_wakeref_t wref) 321{ 322 __intel_runtime_pm_put(rpm, wref, false); 323} 324 325/** 326 * intel_runtime_pm_put_unchecked - release an unchecked runtime pm reference 327 * @rpm: the intel_runtime_pm structure 328 * 329 * This function drops the device-level runtime pm reference obtained by 330 * intel_runtime_pm_get() and might power down the corresponding 331 * hardware block right away if this is the last reference. 332 * 333 * This function exists only for historical reasons and should be avoided in 334 * new code, as the correctness of its use cannot be checked. Always use 335 * intel_runtime_pm_put() instead. 336 */ 337void intel_runtime_pm_put_unchecked(struct intel_runtime_pm *rpm) 338{ 339 __intel_runtime_pm_put(rpm, -1, true); 340} 341 342#if IS_ENABLED(CONFIG_DRM_I915_DEBUG_RUNTIME_PM) 343/** 344 * intel_runtime_pm_put - release a runtime pm reference 345 * @rpm: the intel_runtime_pm structure 346 * @wref: wakeref acquired for the reference that is being released 347 * 348 * This function drops the device-level runtime pm reference obtained by 349 * intel_runtime_pm_get() and might power down the corresponding 350 * hardware block right away if this is the last reference. 351 */ 352void intel_runtime_pm_put(struct intel_runtime_pm *rpm, intel_wakeref_t wref) 353{ 354 __intel_runtime_pm_put(rpm, wref, true); 355} 356#endif 357 358/** 359 * intel_runtime_pm_enable - enable runtime pm 360 * @rpm: the intel_runtime_pm structure 361 * 362 * This function enables runtime pm at the end of the driver load sequence. 363 * 364 * Note that this function does currently not enable runtime pm for the 365 * subordinate display power domains. That is done by 366 * intel_power_domains_enable(). 367 */ 368void intel_runtime_pm_enable(struct intel_runtime_pm *rpm) 369{ 370 struct drm_i915_private *i915 = rpm_to_i915(rpm); 371 struct device *kdev = rpm->kdev; 372 373 /* 374 * Disable the system suspend direct complete optimization, which can 375 * leave the device suspended skipping the driver's suspend handlers 376 * if the device was already runtime suspended. This is needed due to 377 * the difference in our runtime and system suspend sequence and 378 * becaue the HDA driver may require us to enable the audio power 379 * domain during system suspend. 380 */ 381 dev_pm_set_driver_flags(kdev, DPM_FLAG_NO_DIRECT_COMPLETE); 382 383 pm_runtime_set_autosuspend_delay(kdev, 10000); /* 10s */ 384 pm_runtime_mark_last_busy(kdev); 385 386 /* 387 * Take a permanent reference to disable the RPM functionality and drop 388 * it only when unloading the driver. Use the low level get/put helpers, 389 * so the driver's own RPM reference tracking asserts also work on 390 * platforms without RPM support. 391 */ 392 if (!rpm->available) { 393 int ret; 394 395 pm_runtime_dont_use_autosuspend(kdev); 396 ret = pm_runtime_get_sync(kdev); 397 drm_WARN(&i915->drm, ret < 0, 398 "pm_runtime_get_sync() failed: %d\n", ret); 399 } else { 400 pm_runtime_use_autosuspend(kdev); 401 } 402 403 /* 404 * FIXME: Temp hammer to keep autosupend disable on lmem supported platforms. 405 * As per PCIe specs 5.3.1.4.1, all iomem read write request over a PCIe 406 * function will be unsupported in case PCIe endpoint function is in D3. 407 * Let's keep i915 autosuspend control 'on' till we fix all known issue 408 * with lmem access in D3. 409 */ 410 if (!IS_DGFX(i915)) 411 pm_runtime_allow(kdev); 412 413 /* 414 * The core calls the driver load handler with an RPM reference held. 415 * We drop that here and will reacquire it during unloading in 416 * intel_power_domains_fini(). 417 */ 418 pm_runtime_put_autosuspend(kdev); 419} 420 421void intel_runtime_pm_disable(struct intel_runtime_pm *rpm) 422{ 423 struct drm_i915_private *i915 = rpm_to_i915(rpm); 424 struct device *kdev = rpm->kdev; 425 426 /* Transfer rpm ownership back to core */ 427 drm_WARN(&i915->drm, pm_runtime_get_sync(kdev) < 0, 428 "Failed to pass rpm ownership back to core\n"); 429 430 pm_runtime_dont_use_autosuspend(kdev); 431 432 if (!rpm->available) 433 pm_runtime_put(kdev); 434} 435 436void intel_runtime_pm_driver_release(struct intel_runtime_pm *rpm) 437{ 438 struct drm_i915_private *i915 = rpm_to_i915(rpm); 439 int count = atomic_read(&rpm->wakeref_count); 440 441 intel_wakeref_auto_fini(&rpm->userfault_wakeref); 442 443 drm_WARN(&i915->drm, count, 444 "i915 raw-wakerefs=%d wakelocks=%d on cleanup\n", 445 intel_rpm_raw_wakeref_count(count), 446 intel_rpm_wakelock_count(count)); 447} 448 449void intel_runtime_pm_driver_last_release(struct intel_runtime_pm *rpm) 450{ 451 intel_runtime_pm_driver_release(rpm); 452 untrack_all_intel_runtime_pm_wakerefs(rpm); 453} 454 455void intel_runtime_pm_init_early(struct intel_runtime_pm *rpm) 456{ 457 struct drm_i915_private *i915 = rpm_to_i915(rpm); 458 struct pci_dev *pdev = to_pci_dev(i915->drm.dev); 459 struct device *kdev = &pdev->dev; 460 461 rpm->kdev = kdev; 462 rpm->available = HAS_RUNTIME_PM(i915); 463 atomic_set(&rpm->wakeref_count, 0); 464 465 init_intel_runtime_pm_wakeref(rpm); 466 INIT_LIST_HEAD(&rpm->lmem_userfault_list); 467 spin_lock_init(&rpm->lmem_userfault_lock); 468 intel_wakeref_auto_init(&rpm->userfault_wakeref, i915); 469} 470