drivers/gpu/drm/msm/msm_atomic.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2014 Red Hat
   4  * Author: Rob Clark <robdclark@gmail.com>
   5  */
   6
   7 #include <drm/drm_atomic_uapi.h>
   8 #include <drm/drm_vblank.h>
   9
  10 #include "msm_atomic_trace.h"
  11 #include "msm_drv.h"
  12 #include "msm_gem.h"
  13 #include "msm_kms.h"
  14
  15 /*
  16  * Helpers to control vblanks while we flush.. basically just to ensure
  17  * that vblank accounting is switched on, so we get valid seqn/timestamp
  18  * on pageflip events (if requested)
  19  */
  20
  21 static void vblank_get(struct msm_kms *kms, unsigned crtc_mask)
  22 {
  23         struct drm_crtc *crtc;
  24
  25         for_each_crtc_mask(kms->dev, crtc, crtc_mask) {
  26                 if (!crtc->state->active)
  27                         continue;
  28                 drm_crtc_vblank_get(crtc);
  29         }
  30 }
  31
  32 static void vblank_put(struct msm_kms *kms, unsigned crtc_mask)
  33 {
  34         struct drm_crtc *crtc;
  35
  36         for_each_crtc_mask(kms->dev, crtc, crtc_mask) {
  37                 if (!crtc->state->active)
  38                         continue;
  39                 drm_crtc_vblank_put(crtc);
  40         }
  41 }
  42
  43 static void lock_crtcs(struct msm_kms *kms, unsigned int crtc_mask)
  44 {
  45         int crtc_index;
  46         struct drm_crtc *crtc;
  47
  48         for_each_crtc_mask(kms->dev, crtc, crtc_mask) {
  49                 crtc_index = drm_crtc_index(crtc);
  50                 mutex_lock_nested(&kms->commit_lock[crtc_index], crtc_index);
  51         }
  52 }
  53
  54 static void unlock_crtcs(struct msm_kms *kms, unsigned int crtc_mask)
  55 {
  56         struct drm_crtc *crtc;
  57
  58         for_each_crtc_mask_reverse(kms->dev, crtc, crtc_mask)
  59                 mutex_unlock(&kms->commit_lock[drm_crtc_index(crtc)]);
  60 }
  61
  62 static void msm_atomic_async_commit(struct msm_kms *kms, int crtc_idx)
  63 {
  64         unsigned crtc_mask = BIT(crtc_idx);
  65
  66         trace_msm_atomic_async_commit_start(crtc_mask);
  67
  68         lock_crtcs(kms, crtc_mask);
  69
  70         if (!(kms->pending_crtc_mask & crtc_mask)) {
  71                 unlock_crtcs(kms, crtc_mask);
  72                 goto out;
  73         }
  74
  75         kms->pending_crtc_mask &= ~crtc_mask;
  76
  77         kms->funcs->enable_commit(kms);
  78
  79         vblank_get(kms, crtc_mask);
  80
  81         /*
  82          * Flush hardware updates:
  83          */
  84         trace_msm_atomic_flush_commit(crtc_mask);
  85         kms->funcs->flush_commit(kms, crtc_mask);
  86
  87         /*
  88          * Wait for flush to complete:
  89          */
  90         trace_msm_atomic_wait_flush_start(crtc_mask);
  91         kms->funcs->wait_flush(kms, crtc_mask);
  92         trace_msm_atomic_wait_flush_finish(crtc_mask);
  93
  94         vblank_put(kms, crtc_mask);
  95
  96         kms->funcs->complete_commit(kms, crtc_mask);
  97         unlock_crtcs(kms, crtc_mask);
  98         kms->funcs->disable_commit(kms);
  99
 100 out:
 101         trace_msm_atomic_async_commit_finish(crtc_mask);
 102 }
 103
 104 static void msm_atomic_pending_work(struct kthread_work *work)
 105 {
 106         struct msm_pending_timer *timer = container_of(work,
 107                         struct msm_pending_timer, work.work);
 108
 109         msm_atomic_async_commit(timer->kms, timer->crtc_idx);
 110 }
 111
 112 int msm_atomic_init_pending_timer(struct msm_pending_timer *timer,
 113                 struct msm_kms *kms, int crtc_idx)
 114 {
 115         timer->kms = kms;
 116         timer->crtc_idx = crtc_idx;
 117
 118         timer->worker = kthread_create_worker(0, "atomic-worker-%d", crtc_idx);
 119         if (IS_ERR(timer->worker)) {
 120                 int ret = PTR_ERR(timer->worker);
 121                 timer->worker = NULL;
 122                 return ret;
 123         }
 124         sched_set_fifo(timer->worker->task);
 125
 126         msm_hrtimer_work_init(&timer->work, timer->worker,
 127                               msm_atomic_pending_work,
 128                               CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 129
 130         return 0;
 131 }
 132
 133 void msm_atomic_destroy_pending_timer(struct msm_pending_timer *timer)
 134 {
 135         if (timer->worker)
 136                 kthread_destroy_worker(timer->worker);
 137 }
 138
 139 static bool can_do_async(struct drm_atomic_state *state,
 140                 struct drm_crtc **async_crtc)
 141 {
 142         struct drm_connector_state *connector_state;
 143         struct drm_connector *connector;
 144         struct drm_crtc_state *crtc_state;
 145         struct drm_crtc *crtc;
 146         int i, num_crtcs = 0;
 147
 148         if (!(state->legacy_cursor_update || state->async_update))
 149                 return false;
 150
 151         /* any connector change, means slow path: */
 152         for_each_new_connector_in_state(state, connector, connector_state, i)
 153                 return false;
 154
 155         for_each_new_crtc_in_state(state, crtc, crtc_state, i) {
 156                 if (drm_atomic_crtc_needs_modeset(crtc_state))
 157                         return false;
 158                 if (++num_crtcs > 1)
 159                         return false;
 160                 *async_crtc = crtc;
 161         }
 162
 163         return true;
 164 }
 165
 166 /* Get bitmask of crtcs that will need to be flushed.  The bitmask
 167  * can be used with for_each_crtc_mask() iterator, to iterate
 168  * effected crtcs without needing to preserve the atomic state.
 169  */
 170 static unsigned get_crtc_mask(struct drm_atomic_state *state)
 171 {
 172         struct drm_crtc_state *crtc_state;
 173         struct drm_crtc *crtc;
 174         unsigned i, mask = 0;
 175
 176         for_each_new_crtc_in_state(state, crtc, crtc_state, i)
 177                 mask |= drm_crtc_mask(crtc);
 178
 179         return mask;
 180 }
 181
 182 void msm_atomic_commit_tail(struct drm_atomic_state *state)
 183 {
 184         struct drm_device *dev = state->dev;
 185         struct msm_drm_private *priv = dev->dev_private;
 186         struct msm_kms *kms = priv->kms;
 187         struct drm_crtc *async_crtc = NULL;
 188         unsigned crtc_mask = get_crtc_mask(state);
 189         bool async = kms->funcs->vsync_time &&
 190                         can_do_async(state, &async_crtc);
 191
 192         trace_msm_atomic_commit_tail_start(async, crtc_mask);
 193
 194         kms->funcs->enable_commit(kms);
 195
 196         /*
 197          * Ensure any previous (potentially async) commit has
 198          * completed:
 199          */
 200         lock_crtcs(kms, crtc_mask);
 201         trace_msm_atomic_wait_flush_start(crtc_mask);
 202         kms->funcs->wait_flush(kms, crtc_mask);
 203         trace_msm_atomic_wait_flush_finish(crtc_mask);
 204
 205         /*
 206          * Now that there is no in-progress flush, prepare the
 207          * current update:
 208          */
 209         kms->funcs->prepare_commit(kms, state);
 210
 211         /*
 212          * Push atomic updates down to hardware:
 213          */
 214         drm_atomic_helper_commit_modeset_disables(dev, state);
 215         drm_atomic_helper_commit_planes(dev, state, 0);
 216         drm_atomic_helper_commit_modeset_enables(dev, state);
 217
 218         if (async) {
 219                 struct msm_pending_timer *timer =
 220                         &kms->pending_timers[drm_crtc_index(async_crtc)];
 221
 222                 /* async updates are limited to single-crtc updates: */
 223                 WARN_ON(crtc_mask != drm_crtc_mask(async_crtc));
 224
 225                 /*
 226                  * Start timer if we don't already have an update pending
 227                  * on this crtc:
 228                  */
 229                 if (!(kms->pending_crtc_mask & crtc_mask)) {
 230                         ktime_t vsync_time, wakeup_time;
 231
 232                         kms->pending_crtc_mask |= crtc_mask;
 233
 234                         vsync_time = kms->funcs->vsync_time(kms, async_crtc);
 235                         wakeup_time = ktime_sub(vsync_time, ms_to_ktime(1));
 236
 237                         msm_hrtimer_queue_work(&timer->work, wakeup_time,
 238                                         HRTIMER_MODE_ABS);
 239                 }
 240
 241                 kms->funcs->disable_commit(kms);
 242                 unlock_crtcs(kms, crtc_mask);
 243                 /*
 244                  * At this point, from drm core's perspective, we
 245                  * are done with the atomic update, so we can just
 246                  * go ahead and signal that it is done:
 247                  */
 248                 drm_atomic_helper_commit_hw_done(state);
 249                 drm_atomic_helper_cleanup_planes(dev, state);
 250
 251                 trace_msm_atomic_commit_tail_finish(async, crtc_mask);
 252
 253                 return;
 254         }
 255
 256         /*
 257          * If there is any async flush pending on updated crtcs, fold
 258          * them into the current flush.
 259          */
 260         kms->pending_crtc_mask &= ~crtc_mask;
 261
 262         vblank_get(kms, crtc_mask);
 263
 264         /*
 265          * Flush hardware updates:
 266          */
 267         trace_msm_atomic_flush_commit(crtc_mask);
 268         kms->funcs->flush_commit(kms, crtc_mask);
 269         unlock_crtcs(kms, crtc_mask);
 270         /*
 271          * Wait for flush to complete:
 272          */
 273         trace_msm_atomic_wait_flush_start(crtc_mask);
 274         kms->funcs->wait_flush(kms, crtc_mask);
 275         trace_msm_atomic_wait_flush_finish(crtc_mask);
 276
 277         vblank_put(kms, crtc_mask);
 278
 279         lock_crtcs(kms, crtc_mask);
 280         kms->funcs->complete_commit(kms, crtc_mask);
 281         unlock_crtcs(kms, crtc_mask);
 282         kms->funcs->disable_commit(kms);
 283
 284         drm_atomic_helper_commit_hw_done(state);
 285         drm_atomic_helper_cleanup_planes(dev, state);
 286
 287         trace_msm_atomic_commit_tail_finish(async, crtc_mask);
 288 }