drivers/gpu/drm/i915/intel_psr.c

   1 /*
   2  * Copyright © 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
  21  * DEALINGS IN THE SOFTWARE.
  22  */
  23
  24 /**
  25  * DOC: Panel Self Refresh (PSR/SRD)
  26  *
  27  * Since Haswell Display controller supports Panel Self-Refresh on display
  28  * panels witch have a remote frame buffer (RFB) implemented according to PSR
  29  * spec in eDP1.3. PSR feature allows the display to go to lower standby states
  30  * when system is idle but display is on as it eliminates display refresh
  31  * request to DDR memory completely as long as the frame buffer for that
  32  * display is unchanged.
  33  *
  34  * Panel Self Refresh must be supported by both Hardware (source) and
  35  * Panel (sink).
  36  *
  37  * PSR saves power by caching the framebuffer in the panel RFB, which allows us
  38  * to power down the link and memory controller. For DSI panels the same idea
  39  * is called "manual mode".
  40  *
  41  * The implementation uses the hardware-based PSR support which automatically
  42  * enters/exits self-refresh mode. The hardware takes care of sending the
  43  * required DP aux message and could even retrain the link (that part isn't
  44  * enabled yet though). The hardware also keeps track of any frontbuffer
  45  * changes to know when to exit self-refresh mode again. Unfortunately that
  46  * part doesn't work too well, hence why the i915 PSR support uses the
  47  * software frontbuffer tracking to make sure it doesn't miss a screen
  48  * update. For this integration intel_psr_invalidate() and intel_psr_flush()
  49  * get called by the frontbuffer tracking code. Note that because of locking
  50  * issues the self-refresh re-enable code is done from a work queue, which
  51  * must be correctly synchronized/cancelled when shutting down the pipe."
  52  */
  53
  54 #include <drm/drmP.h>
  55
  56 #include "intel_drv.h"
  57 #include "i915_drv.h"
  58
  59 void intel_psr_irq_control(struct drm_i915_private *dev_priv, bool debug)
  60 {
  61         u32 debug_mask, mask;
  62
  63         mask = EDP_PSR_ERROR(TRANSCODER_EDP);
  64         debug_mask = EDP_PSR_POST_EXIT(TRANSCODER_EDP) |
  65                      EDP_PSR_PRE_ENTRY(TRANSCODER_EDP);
  66
  67         if (INTEL_GEN(dev_priv) >= 8) {
  68                 mask |= EDP_PSR_ERROR(TRANSCODER_A) |
  69                         EDP_PSR_ERROR(TRANSCODER_B) |
  70                         EDP_PSR_ERROR(TRANSCODER_C);
  71
  72                 debug_mask |= EDP_PSR_POST_EXIT(TRANSCODER_A) |
  73                               EDP_PSR_PRE_ENTRY(TRANSCODER_A) |
  74                               EDP_PSR_POST_EXIT(TRANSCODER_B) |
  75                               EDP_PSR_PRE_ENTRY(TRANSCODER_B) |
  76                               EDP_PSR_POST_EXIT(TRANSCODER_C) |
  77                               EDP_PSR_PRE_ENTRY(TRANSCODER_C);
  78         }
  79
  80         if (debug)
  81                 mask |= debug_mask;
  82
  83         WRITE_ONCE(dev_priv->psr.debug, debug);
  84         I915_WRITE(EDP_PSR_IMR, ~mask);
  85 }
  86
  87 static void psr_event_print(u32 val, bool psr2_enabled)
  88 {
  89         DRM_DEBUG_KMS("PSR exit events: 0x%x\n", val);
  90         if (val & PSR_EVENT_PSR2_WD_TIMER_EXPIRE)
  91                 DRM_DEBUG_KMS("\tPSR2 watchdog timer expired\n");
  92         if ((val & PSR_EVENT_PSR2_DISABLED) && psr2_enabled)
  93                 DRM_DEBUG_KMS("\tPSR2 disabled\n");
  94         if (val & PSR_EVENT_SU_DIRTY_FIFO_UNDERRUN)
  95                 DRM_DEBUG_KMS("\tSU dirty FIFO underrun\n");
  96         if (val & PSR_EVENT_SU_CRC_FIFO_UNDERRUN)
  97                 DRM_DEBUG_KMS("\tSU CRC FIFO underrun\n");
  98         if (val & PSR_EVENT_GRAPHICS_RESET)
  99                 DRM_DEBUG_KMS("\tGraphics reset\n");
 100         if (val & PSR_EVENT_PCH_INTERRUPT)
 101                 DRM_DEBUG_KMS("\tPCH interrupt\n");
 102         if (val & PSR_EVENT_MEMORY_UP)
 103                 DRM_DEBUG_KMS("\tMemory up\n");
 104         if (val & PSR_EVENT_FRONT_BUFFER_MODIFY)
 105                 DRM_DEBUG_KMS("\tFront buffer modification\n");
 106         if (val & PSR_EVENT_WD_TIMER_EXPIRE)
 107                 DRM_DEBUG_KMS("\tPSR watchdog timer expired\n");
 108         if (val & PSR_EVENT_PIPE_REGISTERS_UPDATE)
 109                 DRM_DEBUG_KMS("\tPIPE registers updated\n");
 110         if (val & PSR_EVENT_REGISTER_UPDATE)
 111                 DRM_DEBUG_KMS("\tRegister updated\n");
 112         if (val & PSR_EVENT_HDCP_ENABLE)
 113                 DRM_DEBUG_KMS("\tHDCP enabled\n");
 114         if (val & PSR_EVENT_KVMR_SESSION_ENABLE)
 115                 DRM_DEBUG_KMS("\tKVMR session enabled\n");
 116         if (val & PSR_EVENT_VBI_ENABLE)
 117                 DRM_DEBUG_KMS("\tVBI enabled\n");
 118         if (val & PSR_EVENT_LPSP_MODE_EXIT)
 119                 DRM_DEBUG_KMS("\tLPSP mode exited\n");
 120         if ((val & PSR_EVENT_PSR_DISABLE) && !psr2_enabled)
 121                 DRM_DEBUG_KMS("\tPSR disabled\n");
 122 }
 123
 124 void intel_psr_irq_handler(struct drm_i915_private *dev_priv, u32 psr_iir)
 125 {
 126         u32 transcoders = BIT(TRANSCODER_EDP);
 127         enum transcoder cpu_transcoder;
 128         ktime_t time_ns =  ktime_get();
 129
 130         if (INTEL_GEN(dev_priv) >= 8)
 131                 transcoders |= BIT(TRANSCODER_A) |
 132                                BIT(TRANSCODER_B) |
 133                                BIT(TRANSCODER_C);
 134
 135         for_each_cpu_transcoder_masked(dev_priv, cpu_transcoder, transcoders) {
 136                 /* FIXME: Exit PSR and link train manually when this happens. */
 137                 if (psr_iir & EDP_PSR_ERROR(cpu_transcoder))
 138                         DRM_DEBUG_KMS("[transcoder %s] PSR aux error\n",
 139                                       transcoder_name(cpu_transcoder));
 140
 141                 if (psr_iir & EDP_PSR_PRE_ENTRY(cpu_transcoder)) {
 142                         dev_priv->psr.last_entry_attempt = time_ns;
 143                         DRM_DEBUG_KMS("[transcoder %s] PSR entry attempt in 2 vblanks\n",
 144                                       transcoder_name(cpu_transcoder));
 145                 }
 146
 147                 if (psr_iir & EDP_PSR_POST_EXIT(cpu_transcoder)) {
 148                         dev_priv->psr.last_exit = time_ns;
 149                         DRM_DEBUG_KMS("[transcoder %s] PSR exit completed\n",
 150                                       transcoder_name(cpu_transcoder));
 151
 152                         if (INTEL_GEN(dev_priv) >= 9) {
 153                                 u32 val = I915_READ(PSR_EVENT(cpu_transcoder));
 154                                 bool psr2_enabled = dev_priv->psr.psr2_enabled;
 155
 156                                 I915_WRITE(PSR_EVENT(cpu_transcoder), val);
 157                                 psr_event_print(val, psr2_enabled);
 158                         }
 159                 }
 160         }
 161 }
 162
 163 static bool intel_dp_get_colorimetry_status(struct intel_dp *intel_dp)
 164 {
 165         uint8_t dprx = 0;
 166
 167         if (drm_dp_dpcd_readb(&intel_dp->aux, DP_DPRX_FEATURE_ENUMERATION_LIST,
 168                               &dprx) != 1)
 169                 return false;
 170         return dprx & DP_VSC_SDP_EXT_FOR_COLORIMETRY_SUPPORTED;
 171 }
 172
 173 static bool intel_dp_get_alpm_status(struct intel_dp *intel_dp)
 174 {
 175         uint8_t alpm_caps = 0;
 176
 177         if (drm_dp_dpcd_readb(&intel_dp->aux, DP_RECEIVER_ALPM_CAP,
 178                               &alpm_caps) != 1)
 179                 return false;
 180         return alpm_caps & DP_ALPM_CAP;
 181 }
 182
 183 static u8 intel_dp_get_sink_sync_latency(struct intel_dp *intel_dp)
 184 {
 185         u8 val = 8; /* assume the worst if we can't read the value */
 186
 187         if (drm_dp_dpcd_readb(&intel_dp->aux,
 188                               DP_SYNCHRONIZATION_LATENCY_IN_SINK, &val) == 1)
 189                 val &= DP_MAX_RESYNC_FRAME_COUNT_MASK;
 190         else
 191                 DRM_DEBUG_KMS("Unable to get sink synchronization latency, assuming 8 frames\n");
 192         return val;
 193 }
 194
 195 void intel_psr_init_dpcd(struct intel_dp *intel_dp)
 196 {
 197         struct drm_i915_private *dev_priv =
 198                 to_i915(dp_to_dig_port(intel_dp)->base.base.dev);
 199
 200         drm_dp_dpcd_read(&intel_dp->aux, DP_PSR_SUPPORT, intel_dp->psr_dpcd,
 201                          sizeof(intel_dp->psr_dpcd));
 202
 203         if (!intel_dp->psr_dpcd[0])
 204                 return;
 205         DRM_DEBUG_KMS("eDP panel supports PSR version %x\n",
 206                       intel_dp->psr_dpcd[0]);
 207
 208         if (!(intel_dp->edp_dpcd[1] & DP_EDP_SET_POWER_CAP)) {
 209                 DRM_DEBUG_KMS("Panel lacks power state control, PSR cannot be enabled\n");
 210                 return;
 211         }
 212         dev_priv->psr.sink_support = true;
 213         dev_priv->psr.sink_sync_latency =
 214                 intel_dp_get_sink_sync_latency(intel_dp);
 215
 216         if (INTEL_GEN(dev_priv) >= 9 &&
 217             (intel_dp->psr_dpcd[0] == DP_PSR2_WITH_Y_COORD_IS_SUPPORTED)) {
 218                 bool y_req = intel_dp->psr_dpcd[1] &
 219                              DP_PSR2_SU_Y_COORDINATE_REQUIRED;
 220                 bool alpm = intel_dp_get_alpm_status(intel_dp);
 221
 222                 /*
 223                  * All panels that supports PSR version 03h (PSR2 +
 224                  * Y-coordinate) can handle Y-coordinates in VSC but we are
 225                  * only sure that it is going to be used when required by the
 226                  * panel. This way panel is capable to do selective update
 227                  * without a aux frame sync.
 228                  *
 229                  * To support PSR version 02h and PSR version 03h without
 230                  * Y-coordinate requirement panels we would need to enable
 231                  * GTC first.
 232                  */
 233                 dev_priv->psr.sink_psr2_support = y_req && alpm;
 234                 DRM_DEBUG_KMS("PSR2 %ssupported\n",
 235                               dev_priv->psr.sink_psr2_support ? "" : "not ");
 236
 237                 if (dev_priv->psr.sink_psr2_support) {
 238                         dev_priv->psr.colorimetry_support =
 239                                 intel_dp_get_colorimetry_status(intel_dp);
 240                 }
 241         }
 242 }
 243
 244 static void intel_psr_setup_vsc(struct intel_dp *intel_dp,
 245                                 const struct intel_crtc_state *crtc_state)
 246 {
 247         struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
 248         struct drm_i915_private *dev_priv = to_i915(intel_dig_port->base.base.dev);
 249         struct edp_vsc_psr psr_vsc;
 250
 251         if (dev_priv->psr.psr2_enabled) {
 252                 /* Prepare VSC Header for SU as per EDP 1.4 spec, Table 6.11 */
 253                 memset(&psr_vsc, 0, sizeof(psr_vsc));
 254                 psr_vsc.sdp_header.HB0 = 0;
 255                 psr_vsc.sdp_header.HB1 = 0x7;
 256                 if (dev_priv->psr.colorimetry_support) {
 257                         psr_vsc.sdp_header.HB2 = 0x5;
 258                         psr_vsc.sdp_header.HB3 = 0x13;
 259                 } else {
 260                         psr_vsc.sdp_header.HB2 = 0x4;
 261                         psr_vsc.sdp_header.HB3 = 0xe;
 262                 }
 263         } else {
 264                 /* Prepare VSC packet as per EDP 1.3 spec, Table 3.10 */
 265                 memset(&psr_vsc, 0, sizeof(psr_vsc));
 266                 psr_vsc.sdp_header.HB0 = 0;
 267                 psr_vsc.sdp_header.HB1 = 0x7;
 268                 psr_vsc.sdp_header.HB2 = 0x2;
 269                 psr_vsc.sdp_header.HB3 = 0x8;
 270         }
 271
 272         intel_dig_port->write_infoframe(&intel_dig_port->base.base, crtc_state,
 273                                         DP_SDP_VSC, &psr_vsc, sizeof(psr_vsc));
 274 }
 275
 276 static void hsw_psr_setup_aux(struct intel_dp *intel_dp)
 277 {
 278         struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
 279         struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
 280         u32 aux_clock_divider, aux_ctl;
 281         int i;
 282         static const uint8_t aux_msg[] = {
 283                 [0] = DP_AUX_NATIVE_WRITE << 4,
 284                 [1] = DP_SET_POWER >> 8,
 285                 [2] = DP_SET_POWER & 0xff,
 286                 [3] = 1 - 1,
 287                 [4] = DP_SET_POWER_D0,
 288         };
 289         u32 psr_aux_mask = EDP_PSR_AUX_CTL_TIME_OUT_MASK |
 290                            EDP_PSR_AUX_CTL_MESSAGE_SIZE_MASK |
 291                            EDP_PSR_AUX_CTL_PRECHARGE_2US_MASK |
 292                            EDP_PSR_AUX_CTL_BIT_CLOCK_2X_MASK;
 293
 294         BUILD_BUG_ON(sizeof(aux_msg) > 20);
 295         for (i = 0; i < sizeof(aux_msg); i += 4)
 296                 I915_WRITE(EDP_PSR_AUX_DATA(i >> 2),
 297                            intel_dp_pack_aux(&aux_msg[i], sizeof(aux_msg) - i));
 298
 299         aux_clock_divider = intel_dp->get_aux_clock_divider(intel_dp, 0);
 300
 301         /* Start with bits set for DDI_AUX_CTL register */
 302         aux_ctl = intel_dp->get_aux_send_ctl(intel_dp, sizeof(aux_msg),
 303                                              aux_clock_divider);
 304
 305         /* Select only valid bits for SRD_AUX_CTL */
 306         aux_ctl &= psr_aux_mask;
 307         I915_WRITE(EDP_PSR_AUX_CTL, aux_ctl);
 308 }
 309
 310 static void intel_psr_enable_sink(struct intel_dp *intel_dp)
 311 {
 312         struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
 313         struct drm_device *dev = dig_port->base.base.dev;
 314         struct drm_i915_private *dev_priv = to_i915(dev);
 315         u8 dpcd_val = DP_PSR_ENABLE;
 316
 317         /* Enable ALPM at sink for psr2 */
 318         if (dev_priv->psr.psr2_enabled) {
 319                 drm_dp_dpcd_writeb(&intel_dp->aux, DP_RECEIVER_ALPM_CONFIG,
 320                                    DP_ALPM_ENABLE);
 321                 dpcd_val |= DP_PSR_ENABLE_PSR2;
 322         }
 323
 324         if (dev_priv->psr.link_standby)
 325                 dpcd_val |= DP_PSR_MAIN_LINK_ACTIVE;
 326         if (!dev_priv->psr.psr2_enabled && INTEL_GEN(dev_priv) >= 8)
 327                 dpcd_val |= DP_PSR_CRC_VERIFICATION;
 328         drm_dp_dpcd_writeb(&intel_dp->aux, DP_PSR_EN_CFG, dpcd_val);
 329
 330         drm_dp_dpcd_writeb(&intel_dp->aux, DP_SET_POWER, DP_SET_POWER_D0);
 331 }
 332
 333 static void hsw_activate_psr1(struct intel_dp *intel_dp)
 334 {
 335         struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
 336         struct drm_device *dev = dig_port->base.base.dev;
 337         struct drm_i915_private *dev_priv = to_i915(dev);
 338         u32 max_sleep_time = 0x1f;
 339         u32 val = EDP_PSR_ENABLE;
 340
 341         /* Let's use 6 as the minimum to cover all known cases including the
 342          * off-by-one issue that HW has in some cases.
 343          */
 344         int idle_frames = max(6, dev_priv->vbt.psr.idle_frames);
 345
 346         /* sink_sync_latency of 8 means source has to wait for more than 8
 347          * frames, we'll go with 9 frames for now
 348          */
 349         idle_frames = max(idle_frames, dev_priv->psr.sink_sync_latency + 1);
 350         val |= idle_frames << EDP_PSR_IDLE_FRAME_SHIFT;
 351
 352         val |= max_sleep_time << EDP_PSR_MAX_SLEEP_TIME_SHIFT;
 353         if (IS_HASWELL(dev_priv))
 354                 val |= EDP_PSR_MIN_LINK_ENTRY_TIME_8_LINES;
 355
 356         if (dev_priv->psr.link_standby)
 357                 val |= EDP_PSR_LINK_STANDBY;
 358
 359         if (dev_priv->vbt.psr.tp1_wakeup_time_us == 0)
 360                 val |=  EDP_PSR_TP1_TIME_0us;
 361         else if (dev_priv->vbt.psr.tp1_wakeup_time_us <= 100)
 362                 val |= EDP_PSR_TP1_TIME_100us;
 363         else if (dev_priv->vbt.psr.tp1_wakeup_time_us <= 500)
 364                 val |= EDP_PSR_TP1_TIME_500us;
 365         else
 366                 val |= EDP_PSR_TP1_TIME_2500us;
 367
 368         if (dev_priv->vbt.psr.tp2_tp3_wakeup_time_us == 0)
 369                 val |=  EDP_PSR_TP2_TP3_TIME_0us;
 370         else if (dev_priv->vbt.psr.tp2_tp3_wakeup_time_us <= 100)
 371                 val |= EDP_PSR_TP2_TP3_TIME_100us;
 372         else if (dev_priv->vbt.psr.tp2_tp3_wakeup_time_us <= 500)
 373                 val |= EDP_PSR_TP2_TP3_TIME_500us;
 374         else
 375                 val |= EDP_PSR_TP2_TP3_TIME_2500us;
 376
 377         if (intel_dp_source_supports_hbr2(intel_dp) &&
 378             drm_dp_tps3_supported(intel_dp->dpcd))
 379                 val |= EDP_PSR_TP1_TP3_SEL;
 380         else
 381                 val |= EDP_PSR_TP1_TP2_SEL;
 382
 383         if (INTEL_GEN(dev_priv) >= 8)
 384                 val |= EDP_PSR_CRC_ENABLE;
 385
 386         val |= I915_READ(EDP_PSR_CTL) & EDP_PSR_RESTORE_PSR_ACTIVE_CTX_MASK;
 387         I915_WRITE(EDP_PSR_CTL, val);
 388 }
 389
 390 static void hsw_activate_psr2(struct intel_dp *intel_dp)
 391 {
 392         struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
 393         struct drm_device *dev = dig_port->base.base.dev;
 394         struct drm_i915_private *dev_priv = to_i915(dev);
 395         u32 val;
 396
 397         /* Let's use 6 as the minimum to cover all known cases including the
 398          * off-by-one issue that HW has in some cases.
 399          */
 400         int idle_frames = max(6, dev_priv->vbt.psr.idle_frames);
 401
 402         idle_frames = max(idle_frames, dev_priv->psr.sink_sync_latency + 1);
 403         val = idle_frames << EDP_PSR2_IDLE_FRAME_SHIFT;
 404
 405         /* FIXME: selective update is probably totally broken because it doesn't
 406          * mesh at all with our frontbuffer tracking. And the hw alone isn't
 407          * good enough. */
 408         val |= EDP_PSR2_ENABLE | EDP_SU_TRACK_ENABLE;
 409         if (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv))
 410                 val |= EDP_Y_COORDINATE_ENABLE;
 411
 412         val |= EDP_PSR2_FRAME_BEFORE_SU(dev_priv->psr.sink_sync_latency + 1);
 413
 414         if (dev_priv->vbt.psr.tp2_tp3_wakeup_time_us >= 0 &&
 415             dev_priv->vbt.psr.tp2_tp3_wakeup_time_us <= 50)
 416                 val |= EDP_PSR2_TP2_TIME_50us;
 417         else if (dev_priv->vbt.psr.tp2_tp3_wakeup_time_us <= 100)
 418                 val |= EDP_PSR2_TP2_TIME_100us;
 419         else if (dev_priv->vbt.psr.tp2_tp3_wakeup_time_us <= 500)
 420                 val |= EDP_PSR2_TP2_TIME_500us;
 421         else
 422                 val |= EDP_PSR2_TP2_TIME_2500us;
 423
 424         I915_WRITE(EDP_PSR2_CTL, val);
 425 }
 426
 427 static bool intel_psr2_config_valid(struct intel_dp *intel_dp,
 428                                     struct intel_crtc_state *crtc_state)
 429 {
 430         struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
 431         struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
 432         int crtc_hdisplay = crtc_state->base.adjusted_mode.crtc_hdisplay;
 433         int crtc_vdisplay = crtc_state->base.adjusted_mode.crtc_vdisplay;
 434         int psr_max_h = 0, psr_max_v = 0;
 435
 436         /*
 437          * FIXME psr2_support is messed up. It's both computed
 438          * dynamically during PSR enable, and extracted from sink
 439          * caps during eDP detection.
 440          */
 441         if (!dev_priv->psr.sink_psr2_support)
 442                 return false;
 443
 444         if (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv)) {
 445                 psr_max_h = 4096;
 446                 psr_max_v = 2304;
 447         } else if (IS_GEN9(dev_priv)) {
 448                 psr_max_h = 3640;
 449                 psr_max_v = 2304;
 450         }
 451
 452         if (crtc_hdisplay > psr_max_h || crtc_vdisplay > psr_max_v) {
 453                 DRM_DEBUG_KMS("PSR2 not enabled, resolution %dx%d > max supported %dx%d\n",
 454                               crtc_hdisplay, crtc_vdisplay,
 455                               psr_max_h, psr_max_v);
 456                 return false;
 457         }
 458
 459         return true;
 460 }
 461
 462 void intel_psr_compute_config(struct intel_dp *intel_dp,
 463                               struct intel_crtc_state *crtc_state)
 464 {
 465         struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
 466         struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
 467         const struct drm_display_mode *adjusted_mode =
 468                 &crtc_state->base.adjusted_mode;
 469         int psr_setup_time;
 470
 471         if (!CAN_PSR(dev_priv))
 472                 return;
 473
 474         if (!i915_modparams.enable_psr) {
 475                 DRM_DEBUG_KMS("PSR disable by flag\n");
 476                 return;
 477         }
 478
 479         /*
 480          * HSW spec explicitly says PSR is tied to port A.
 481          * BDW+ platforms with DDI implementation of PSR have different
 482          * PSR registers per transcoder and we only implement transcoder EDP
 483          * ones. Since by Display design transcoder EDP is tied to port A
 484          * we can safely escape based on the port A.
 485          */
 486         if (dig_port->base.port != PORT_A) {
 487                 DRM_DEBUG_KMS("PSR condition failed: Port not supported\n");
 488                 return;
 489         }
 490
 491         if (IS_HASWELL(dev_priv) &&
 492             I915_READ(HSW_STEREO_3D_CTL(crtc_state->cpu_transcoder)) &
 493                       S3D_ENABLE) {
 494                 DRM_DEBUG_KMS("PSR condition failed: Stereo 3D is Enabled\n");
 495                 return;
 496         }
 497
 498         if (IS_HASWELL(dev_priv) &&
 499             adjusted_mode->flags & DRM_MODE_FLAG_INTERLACE) {
 500                 DRM_DEBUG_KMS("PSR condition failed: Interlaced is Enabled\n");
 501                 return;
 502         }
 503
 504         psr_setup_time = drm_dp_psr_setup_time(intel_dp->psr_dpcd);
 505         if (psr_setup_time < 0) {
 506                 DRM_DEBUG_KMS("PSR condition failed: Invalid PSR setup time (0x%02x)\n",
 507                               intel_dp->psr_dpcd[1]);
 508                 return;
 509         }
 510
 511         if (intel_usecs_to_scanlines(adjusted_mode, psr_setup_time) >
 512             adjusted_mode->crtc_vtotal - adjusted_mode->crtc_vdisplay - 1) {
 513                 DRM_DEBUG_KMS("PSR condition failed: PSR setup time (%d us) too long\n",
 514                               psr_setup_time);
 515                 return;
 516         }
 517
 518         crtc_state->has_psr = true;
 519         crtc_state->has_psr2 = intel_psr2_config_valid(intel_dp, crtc_state);
 520         DRM_DEBUG_KMS("Enabling PSR%s\n", crtc_state->has_psr2 ? "2" : "");
 521 }
 522
 523 static void intel_psr_activate(struct intel_dp *intel_dp)
 524 {
 525         struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
 526         struct drm_device *dev = intel_dig_port->base.base.dev;
 527         struct drm_i915_private *dev_priv = to_i915(dev);
 528
 529         if (INTEL_GEN(dev_priv) >= 9)
 530                 WARN_ON(I915_READ(EDP_PSR2_CTL) & EDP_PSR2_ENABLE);
 531         WARN_ON(I915_READ(EDP_PSR_CTL) & EDP_PSR_ENABLE);
 532         WARN_ON(dev_priv->psr.active);
 533         lockdep_assert_held(&dev_priv->psr.lock);
 534
 535         /* psr1 and psr2 are mutually exclusive.*/
 536         if (dev_priv->psr.psr2_enabled)
 537                 hsw_activate_psr2(intel_dp);
 538         else
 539                 hsw_activate_psr1(intel_dp);
 540
 541         dev_priv->psr.active = true;
 542 }
 543
 544 static void intel_psr_enable_source(struct intel_dp *intel_dp,
 545                                     const struct intel_crtc_state *crtc_state)
 546 {
 547         struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
 548         struct drm_device *dev = dig_port->base.base.dev;
 549         struct drm_i915_private *dev_priv = to_i915(dev);
 550         enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
 551
 552         /* Only HSW and BDW have PSR AUX registers that need to be setup. SKL+
 553          * use hardcoded values PSR AUX transactions
 554          */
 555         if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
 556                 hsw_psr_setup_aux(intel_dp);
 557
 558         if (dev_priv->psr.psr2_enabled) {
 559                 u32 chicken = I915_READ(CHICKEN_TRANS(cpu_transcoder));
 560
 561                 if (INTEL_GEN(dev_priv) == 9 && !IS_GEMINILAKE(dev_priv))
 562                         chicken |= (PSR2_VSC_ENABLE_PROG_HEADER
 563                                    | PSR2_ADD_VERTICAL_LINE_COUNT);
 564
 565                 else
 566                         chicken &= ~VSC_DATA_SEL_SOFTWARE_CONTROL;
 567                 I915_WRITE(CHICKEN_TRANS(cpu_transcoder), chicken);
 568
 569                 I915_WRITE(EDP_PSR_DEBUG,
 570                            EDP_PSR_DEBUG_MASK_MEMUP |
 571                            EDP_PSR_DEBUG_MASK_HPD |
 572                            EDP_PSR_DEBUG_MASK_LPSP |
 573                            EDP_PSR_DEBUG_MASK_MAX_SLEEP |
 574                            EDP_PSR_DEBUG_MASK_DISP_REG_WRITE);
 575         } else {
 576                 /*
 577                  * Per Spec: Avoid continuous PSR exit by masking MEMUP
 578                  * and HPD. also mask LPSP to avoid dependency on other
 579                  * drivers that might block runtime_pm besides
 580                  * preventing  other hw tracking issues now we can rely
 581                  * on frontbuffer tracking.
 582                  */
 583                 I915_WRITE(EDP_PSR_DEBUG,
 584                            EDP_PSR_DEBUG_MASK_MEMUP |
 585                            EDP_PSR_DEBUG_MASK_HPD |
 586                            EDP_PSR_DEBUG_MASK_LPSP |
 587                            EDP_PSR_DEBUG_MASK_DISP_REG_WRITE |
 588                            EDP_PSR_DEBUG_MASK_MAX_SLEEP);
 589         }
 590 }
 591
 592 /**
 593  * intel_psr_enable - Enable PSR
 594  * @intel_dp: Intel DP
 595  * @crtc_state: new CRTC state
 596  *
 597  * This function can only be called after the pipe is fully trained and enabled.
 598  */
 599 void intel_psr_enable(struct intel_dp *intel_dp,
 600                       const struct intel_crtc_state *crtc_state)
 601 {
 602         struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
 603         struct drm_device *dev = intel_dig_port->base.base.dev;
 604         struct drm_i915_private *dev_priv = to_i915(dev);
 605
 606         if (!crtc_state->has_psr)
 607                 return;
 608
 609         if (WARN_ON(!CAN_PSR(dev_priv)))
 610                 return;
 611
 612         WARN_ON(dev_priv->drrs.dp);
 613         mutex_lock(&dev_priv->psr.lock);
 614         if (dev_priv->psr.enabled) {
 615                 DRM_DEBUG_KMS("PSR already in use\n");
 616                 goto unlock;
 617         }
 618
 619         dev_priv->psr.psr2_enabled = crtc_state->has_psr2;
 620         dev_priv->psr.busy_frontbuffer_bits = 0;
 621
 622         intel_psr_setup_vsc(intel_dp, crtc_state);
 623         intel_psr_enable_sink(intel_dp);
 624         intel_psr_enable_source(intel_dp, crtc_state);
 625         dev_priv->psr.enabled = intel_dp;
 626
 627         intel_psr_activate(intel_dp);
 628
 629 unlock:
 630         mutex_unlock(&dev_priv->psr.lock);
 631 }
 632
 633 static void
 634 intel_psr_disable_source(struct intel_dp *intel_dp)
 635 {
 636         struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
 637         struct drm_device *dev = intel_dig_port->base.base.dev;
 638         struct drm_i915_private *dev_priv = to_i915(dev);
 639
 640         if (dev_priv->psr.active) {
 641                 i915_reg_t psr_status;
 642                 u32 psr_status_mask;
 643
 644                 if (dev_priv->psr.psr2_enabled) {
 645                         psr_status = EDP_PSR2_STATUS;
 646                         psr_status_mask = EDP_PSR2_STATUS_STATE_MASK;
 647
 648                         I915_WRITE(EDP_PSR2_CTL,
 649                                    I915_READ(EDP_PSR2_CTL) &
 650                                    ~(EDP_PSR2_ENABLE | EDP_SU_TRACK_ENABLE));
 651
 652                 } else {
 653                         psr_status = EDP_PSR_STATUS;
 654                         psr_status_mask = EDP_PSR_STATUS_STATE_MASK;
 655
 656                         I915_WRITE(EDP_PSR_CTL,
 657                                    I915_READ(EDP_PSR_CTL) & ~EDP_PSR_ENABLE);
 658                 }
 659
 660                 /* Wait till PSR is idle */
 661                 if (intel_wait_for_register(dev_priv,
 662                                             psr_status, psr_status_mask, 0,
 663                                             2000))
 664                         DRM_ERROR("Timed out waiting for PSR Idle State\n");
 665
 666                 dev_priv->psr.active = false;
 667         } else {
 668                 if (dev_priv->psr.psr2_enabled)
 669                         WARN_ON(I915_READ(EDP_PSR2_CTL) & EDP_PSR2_ENABLE);
 670                 else
 671                         WARN_ON(I915_READ(EDP_PSR_CTL) & EDP_PSR_ENABLE);
 672         }
 673 }
 674
 675 static void intel_psr_disable_locked(struct intel_dp *intel_dp)
 676 {
 677         struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
 678         struct drm_device *dev = intel_dig_port->base.base.dev;
 679         struct drm_i915_private *dev_priv = to_i915(dev);
 680
 681         lockdep_assert_held(&dev_priv->psr.lock);
 682
 683         if (!dev_priv->psr.enabled)
 684                 return;
 685
 686         intel_psr_disable_source(intel_dp);
 687
 688         /* Disable PSR on Sink */
 689         drm_dp_dpcd_writeb(&intel_dp->aux, DP_PSR_EN_CFG, 0);
 690
 691         dev_priv->psr.enabled = NULL;
 692 }
 693
 694 /**
 695  * intel_psr_disable - Disable PSR
 696  * @intel_dp: Intel DP
 697  * @old_crtc_state: old CRTC state
 698  *
 699  * This function needs to be called before disabling pipe.
 700  */
 701 void intel_psr_disable(struct intel_dp *intel_dp,
 702                        const struct intel_crtc_state *old_crtc_state)
 703 {
 704         struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
 705         struct drm_device *dev = intel_dig_port->base.base.dev;
 706         struct drm_i915_private *dev_priv = to_i915(dev);
 707
 708         if (!old_crtc_state->has_psr)
 709                 return;
 710
 711         if (WARN_ON(!CAN_PSR(dev_priv)))
 712                 return;
 713
 714         mutex_lock(&dev_priv->psr.lock);
 715         intel_psr_disable_locked(intel_dp);
 716         mutex_unlock(&dev_priv->psr.lock);
 717         cancel_work_sync(&dev_priv->psr.work);
 718 }
 719
 720 int intel_psr_wait_for_idle(const struct intel_crtc_state *new_crtc_state)
 721 {
 722         struct intel_crtc *crtc = to_intel_crtc(new_crtc_state->base.crtc);
 723         struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 724         i915_reg_t reg;
 725         u32 mask;
 726
 727         if (!new_crtc_state->has_psr)
 728                 return 0;
 729
 730         /*
 731          * The sole user right now is intel_pipe_update_start(),
 732          * which won't race with psr_enable/disable, which is
 733          * where psr2_enabled is written to. So, we don't need
 734          * to acquire the psr.lock. More importantly, we want the
 735          * latency inside intel_pipe_update_start() to be as low
 736          * as possible, so no need to acquire psr.lock when it is
 737          * not needed and will induce latencies in the atomic
 738          * update path.
 739          */
 740         if (dev_priv->psr.psr2_enabled) {
 741                 reg = EDP_PSR2_STATUS;
 742                 mask = EDP_PSR2_STATUS_STATE_MASK;
 743         } else {
 744                 reg = EDP_PSR_STATUS;
 745                 mask = EDP_PSR_STATUS_STATE_MASK;
 746         }
 747
 748         /*
 749          * Max time for PSR to idle = Inverse of the refresh rate +
 750          * 6 ms of exit training time + 1.5 ms of aux channel
 751          * handshake. 50 msec is defesive enough to cover everything.
 752          */
 753         return intel_wait_for_register(dev_priv, reg, mask,
 754                                        EDP_PSR_STATUS_STATE_IDLE, 50);
 755 }
 756
 757 static bool __psr_wait_for_idle_locked(struct drm_i915_private *dev_priv)
 758 {
 759         struct intel_dp *intel_dp;
 760         i915_reg_t reg;
 761         u32 mask;
 762         int err;
 763
 764         intel_dp = dev_priv->psr.enabled;
 765         if (!intel_dp)
 766                 return false;
 767
 768         if (dev_priv->psr.psr2_enabled) {
 769                 reg = EDP_PSR2_STATUS;
 770                 mask = EDP_PSR2_STATUS_STATE_MASK;
 771         } else {
 772                 reg = EDP_PSR_STATUS;
 773                 mask = EDP_PSR_STATUS_STATE_MASK;
 774         }
 775
 776         mutex_unlock(&dev_priv->psr.lock);
 777
 778         err = intel_wait_for_register(dev_priv, reg, mask, 0, 50);
 779         if (err)
 780                 DRM_ERROR("Timed out waiting for PSR Idle for re-enable\n");
 781
 782         /* After the unlocked wait, verify that PSR is still wanted! */
 783         mutex_lock(&dev_priv->psr.lock);
 784         return err == 0 && dev_priv->psr.enabled;
 785 }
 786
 787 static void intel_psr_work(struct work_struct *work)
 788 {
 789         struct drm_i915_private *dev_priv =
 790                 container_of(work, typeof(*dev_priv), psr.work);
 791
 792         mutex_lock(&dev_priv->psr.lock);
 793
 794         if (!dev_priv->psr.enabled)
 795                 goto unlock;
 796
 797         /*
 798          * We have to make sure PSR is ready for re-enable
 799          * otherwise it keeps disabled until next full enable/disable cycle.
 800          * PSR might take some time to get fully disabled
 801          * and be ready for re-enable.
 802          */
 803         if (!__psr_wait_for_idle_locked(dev_priv))
 804                 goto unlock;
 805
 806         /*
 807          * The delayed work can race with an invalidate hence we need to
 808          * recheck. Since psr_flush first clears this and then reschedules we
 809          * won't ever miss a flush when bailing out here.
 810          */
 811         if (dev_priv->psr.busy_frontbuffer_bits || dev_priv->psr.active)
 812                 goto unlock;
 813
 814         intel_psr_activate(dev_priv->psr.enabled);
 815 unlock:
 816         mutex_unlock(&dev_priv->psr.lock);
 817 }
 818
 819 static void intel_psr_exit(struct drm_i915_private *dev_priv)
 820 {
 821         u32 val;
 822
 823         if (!dev_priv->psr.active)
 824                 return;
 825
 826         if (dev_priv->psr.psr2_enabled) {
 827                 val = I915_READ(EDP_PSR2_CTL);
 828                 WARN_ON(!(val & EDP_PSR2_ENABLE));
 829                 I915_WRITE(EDP_PSR2_CTL, val & ~EDP_PSR2_ENABLE);
 830         } else {
 831                 val = I915_READ(EDP_PSR_CTL);
 832                 WARN_ON(!(val & EDP_PSR_ENABLE));
 833                 I915_WRITE(EDP_PSR_CTL, val & ~EDP_PSR_ENABLE);
 834         }
 835         dev_priv->psr.active = false;
 836 }
 837
 838 /**
 839  * intel_psr_invalidate - Invalidade PSR
 840  * @dev_priv: i915 device
 841  * @frontbuffer_bits: frontbuffer plane tracking bits
 842  * @origin: which operation caused the invalidate
 843  *
 844  * Since the hardware frontbuffer tracking has gaps we need to integrate
 845  * with the software frontbuffer tracking. This function gets called every
 846  * time frontbuffer rendering starts and a buffer gets dirtied. PSR must be
 847  * disabled if the frontbuffer mask contains a buffer relevant to PSR.
 848  *
 849  * Dirty frontbuffers relevant to PSR are tracked in busy_frontbuffer_bits."
 850  */
 851 void intel_psr_invalidate(struct drm_i915_private *dev_priv,
 852                           unsigned frontbuffer_bits, enum fb_op_origin origin)
 853 {
 854         struct drm_crtc *crtc;
 855         enum pipe pipe;
 856
 857         if (!CAN_PSR(dev_priv))
 858                 return;
 859
 860         if (origin == ORIGIN_FLIP)
 861                 return;
 862
 863         mutex_lock(&dev_priv->psr.lock);
 864         if (!dev_priv->psr.enabled) {
 865                 mutex_unlock(&dev_priv->psr.lock);
 866                 return;
 867         }
 868
 869         crtc = dp_to_dig_port(dev_priv->psr.enabled)->base.base.crtc;
 870         pipe = to_intel_crtc(crtc)->pipe;
 871
 872         frontbuffer_bits &= INTEL_FRONTBUFFER_ALL_MASK(pipe);
 873         dev_priv->psr.busy_frontbuffer_bits |= frontbuffer_bits;
 874
 875         if (frontbuffer_bits)
 876                 intel_psr_exit(dev_priv);
 877
 878         mutex_unlock(&dev_priv->psr.lock);
 879 }
 880
 881 /**
 882  * intel_psr_flush - Flush PSR
 883  * @dev_priv: i915 device
 884  * @frontbuffer_bits: frontbuffer plane tracking bits
 885  * @origin: which operation caused the flush
 886  *
 887  * Since the hardware frontbuffer tracking has gaps we need to integrate
 888  * with the software frontbuffer tracking. This function gets called every
 889  * time frontbuffer rendering has completed and flushed out to memory. PSR
 890  * can be enabled again if no other frontbuffer relevant to PSR is dirty.
 891  *
 892  * Dirty frontbuffers relevant to PSR are tracked in busy_frontbuffer_bits.
 893  */
 894 void intel_psr_flush(struct drm_i915_private *dev_priv,
 895                      unsigned frontbuffer_bits, enum fb_op_origin origin)
 896 {
 897         struct drm_crtc *crtc;
 898         enum pipe pipe;
 899
 900         if (!CAN_PSR(dev_priv))
 901                 return;
 902
 903         if (origin == ORIGIN_FLIP)
 904                 return;
 905
 906         mutex_lock(&dev_priv->psr.lock);
 907         if (!dev_priv->psr.enabled) {
 908                 mutex_unlock(&dev_priv->psr.lock);
 909                 return;
 910         }
 911
 912         crtc = dp_to_dig_port(dev_priv->psr.enabled)->base.base.crtc;
 913         pipe = to_intel_crtc(crtc)->pipe;
 914
 915         frontbuffer_bits &= INTEL_FRONTBUFFER_ALL_MASK(pipe);
 916         dev_priv->psr.busy_frontbuffer_bits &= ~frontbuffer_bits;
 917
 918         /* By definition flush = invalidate + flush */
 919         if (frontbuffer_bits) {
 920                 if (dev_priv->psr.psr2_enabled) {
 921                         intel_psr_exit(dev_priv);
 922                 } else {
 923                         /*
 924                          * Display WA #0884: all
 925                          * This documented WA for bxt can be safely applied
 926                          * broadly so we can force HW tracking to exit PSR
 927                          * instead of disabling and re-enabling.
 928                          * Workaround tells us to write 0 to CUR_SURFLIVE_A,
 929                          * but it makes more sense write to the current active
 930                          * pipe.
 931                          */
 932                         I915_WRITE(CURSURFLIVE(pipe), 0);
 933                 }
 934         }
 935
 936         if (!dev_priv->psr.active && !dev_priv->psr.busy_frontbuffer_bits)
 937                 schedule_work(&dev_priv->psr.work);
 938         mutex_unlock(&dev_priv->psr.lock);
 939 }
 940
 941 /**
 942  * intel_psr_init - Init basic PSR work and mutex.
 943  * @dev_priv: i915 device private
 944  *
 945  * This function is  called only once at driver load to initialize basic
 946  * PSR stuff.
 947  */
 948 void intel_psr_init(struct drm_i915_private *dev_priv)
 949 {
 950         if (!HAS_PSR(dev_priv))
 951                 return;
 952
 953         dev_priv->psr_mmio_base = IS_HASWELL(dev_priv) ?
 954                 HSW_EDP_PSR_BASE : BDW_EDP_PSR_BASE;
 955
 956         if (!dev_priv->psr.sink_support)
 957                 return;
 958
 959         if (i915_modparams.enable_psr == -1) {
 960                 i915_modparams.enable_psr = dev_priv->vbt.psr.enable;
 961
 962                 /* Per platform default: all disabled. */
 963                 i915_modparams.enable_psr = 0;
 964         }
 965
 966         /* Set link_standby x link_off defaults */
 967         if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
 968                 /* HSW and BDW require workarounds that we don't implement. */
 969                 dev_priv->psr.link_standby = false;
 970         else
 971                 /* For new platforms let's respect VBT back again */
 972                 dev_priv->psr.link_standby = dev_priv->vbt.psr.full_link;
 973
 974         INIT_WORK(&dev_priv->psr.work, intel_psr_work);
 975         mutex_init(&dev_priv->psr.lock);
 976 }
 977
 978 void intel_psr_short_pulse(struct intel_dp *intel_dp)
 979 {
 980         struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
 981         struct drm_device *dev = intel_dig_port->base.base.dev;
 982         struct drm_i915_private *dev_priv = to_i915(dev);
 983         struct i915_psr *psr = &dev_priv->psr;
 984         u8 val;
 985         const u8 errors = DP_PSR_RFB_STORAGE_ERROR |
 986                           DP_PSR_VSC_SDP_UNCORRECTABLE_ERROR |
 987                           DP_PSR_LINK_CRC_ERROR;
 988
 989         if (!CAN_PSR(dev_priv) || !intel_dp_is_edp(intel_dp))
 990                 return;
 991
 992         mutex_lock(&psr->lock);
 993
 994         if (psr->enabled != intel_dp)
 995                 goto exit;
 996
 997         if (drm_dp_dpcd_readb(&intel_dp->aux, DP_PSR_STATUS, &val) != 1) {
 998                 DRM_ERROR("PSR_STATUS dpcd read failed\n");
 999                 goto exit;
1000         }
1001
1002         if ((val & DP_PSR_SINK_STATE_MASK) == DP_PSR_SINK_INTERNAL_ERROR) {
1003                 DRM_DEBUG_KMS("PSR sink internal error, disabling PSR\n");
1004                 intel_psr_disable_locked(intel_dp);
1005         }
1006
1007         if (drm_dp_dpcd_readb(&intel_dp->aux, DP_PSR_ERROR_STATUS, &val) != 1) {
1008                 DRM_ERROR("PSR_ERROR_STATUS dpcd read failed\n");
1009                 goto exit;
1010         }
1011
1012         if (val & DP_PSR_RFB_STORAGE_ERROR)
1013                 DRM_DEBUG_KMS("PSR RFB storage error, disabling PSR\n");
1014         if (val & DP_PSR_VSC_SDP_UNCORRECTABLE_ERROR)
1015                 DRM_DEBUG_KMS("PSR VSC SDP uncorrectable error, disabling PSR\n");
1016         if (val & DP_PSR_LINK_CRC_ERROR)
1017                 DRM_ERROR("PSR Link CRC error, disabling PSR\n");
1018
1019         if (val & ~errors)
1020                 DRM_ERROR("PSR_ERROR_STATUS unhandled errors %x\n",
1021                           val & ~errors);
1022         if (val & errors)
1023                 intel_psr_disable_locked(intel_dp);
1024         /* clear status register */
1025         drm_dp_dpcd_writeb(&intel_dp->aux, DP_PSR_ERROR_STATUS, val);
1026
1027         /* TODO: handle PSR2 errors */
1028 exit:
1029         mutex_unlock(&psr->lock);
1030 }