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_gem_framebuffer_helper.h>
   9 #include <drm/drm_vblank.h>
  10
  11 #include "msm_atomic_trace.h"
  12 #include "msm_drv.h"
  13 #include "msm_gem.h"
  14 #include "msm_kms.h"
  15
  16 int msm_atomic_prepare_fb(struct drm_plane *plane,
  17                           struct drm_plane_state *new_state)
  18 {
  19         struct msm_drm_private *priv = plane->dev->dev_private;
  20         struct msm_kms *kms = priv->kms;
  21
  22         if (!new_state->fb)
  23                 return 0;
  24
  25         drm_gem_fb_prepare_fb(plane, new_state);
  26
  27         return msm_framebuffer_prepare(new_state->fb, kms->aspace);
  28 }
  29
  30 /*
  31  * Helpers to control vblanks while we flush.. basically just to ensure
  32  * that vblank accounting is switched on, so we get valid seqn/timestamp
  33  * on pageflip events (if requested)
  34  */
  35
  36 static void vblank_get(struct msm_kms *kms, unsigned crtc_mask)
  37 {
  38         struct drm_crtc *crtc;
  39
  40         for_each_crtc_mask(kms->dev, crtc, crtc_mask) {
  41                 if (!crtc->state->active)
  42                         continue;
  43                 drm_crtc_vblank_get(crtc);
  44         }
  45 }
  46
  47 static void vblank_put(struct msm_kms *kms, unsigned crtc_mask)
  48 {
  49         struct drm_crtc *crtc;
  50
  51         for_each_crtc_mask(kms->dev, crtc, crtc_mask) {
  52                 if (!crtc->state->active)
  53                         continue;
  54                 drm_crtc_vblank_put(crtc);
  55         }
  56 }
  57
  58 static void lock_crtcs(struct msm_kms *kms, unsigned int crtc_mask)
  59 {
  60         struct drm_crtc *crtc;
  61
  62         for_each_crtc_mask(kms->dev, crtc, crtc_mask)
  63                 mutex_lock(&kms->commit_lock[drm_crtc_index(crtc)]);
  64 }
  65
  66 static void unlock_crtcs(struct msm_kms *kms, unsigned int crtc_mask)
  67 {
  68         struct drm_crtc *crtc;
  69
  70         for_each_crtc_mask_reverse(kms->dev, crtc, crtc_mask)
  71                 mutex_unlock(&kms->commit_lock[drm_crtc_index(crtc)]);
  72 }
  73
  74 static void msm_atomic_async_commit(struct msm_kms *kms, int crtc_idx)
  75 {
  76         unsigned crtc_mask = BIT(crtc_idx);
  77
  78         trace_msm_atomic_async_commit_start(crtc_mask);
  79
  80         lock_crtcs(kms, crtc_mask);
  81
  82         if (!(kms->pending_crtc_mask & crtc_mask)) {
  83                 unlock_crtcs(kms, crtc_mask);
  84                 goto out;
  85         }
  86
  87         kms->pending_crtc_mask &= ~crtc_mask;
  88
  89         kms->funcs->enable_commit(kms);
  90
  91         vblank_get(kms, crtc_mask);
  92
  93         /*
  94          * Flush hardware updates:
  95          */
  96         trace_msm_atomic_flush_commit(crtc_mask);
  97         kms->funcs->flush_commit(kms, crtc_mask);
  98
  99         /*
 100          * Wait for flush to complete:
 101          */
 102         trace_msm_atomic_wait_flush_start(crtc_mask);
 103         kms->funcs->wait_flush(kms, crtc_mask);
 104         trace_msm_atomic_wait_flush_finish(crtc_mask);
 105
 106         vblank_put(kms, crtc_mask);
 107
 108         kms->funcs->complete_commit(kms, crtc_mask);
 109         unlock_crtcs(kms, crtc_mask);
 110         kms->funcs->disable_commit(kms);
 111
 112 out:
 113         trace_msm_atomic_async_commit_finish(crtc_mask);
 114 }
 115
 116 static enum hrtimer_restart msm_atomic_pending_timer(struct hrtimer *t)
 117 {
 118         struct msm_pending_timer *timer = container_of(t,
 119                         struct msm_pending_timer, timer);
 120
 121         kthread_queue_work(timer->worker, &timer->work);
 122
 123         return HRTIMER_NORESTART;
 124 }
 125
 126 static void msm_atomic_pending_work(struct kthread_work *work)
 127 {
 128         struct msm_pending_timer *timer = container_of(work,
 129                         struct msm_pending_timer, work);
 130
 131         msm_atomic_async_commit(timer->kms, timer->crtc_idx);
 132 }
 133
 134 int msm_atomic_init_pending_timer(struct msm_pending_timer *timer,
 135                 struct msm_kms *kms, int crtc_idx)
 136 {
 137         timer->kms = kms;
 138         timer->crtc_idx = crtc_idx;
 139         hrtimer_init(&timer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 140         timer->timer.function = msm_atomic_pending_timer;
 141
 142         timer->worker = kthread_create_worker(0, "atomic-worker-%d", crtc_idx);
 143         if (IS_ERR(timer->worker)) {
 144                 int ret = PTR_ERR(timer->worker);
 145                 timer->worker = NULL;
 146                 return ret;
 147         }
 148         sched_set_fifo(timer->worker->task);
 149         kthread_init_work(&timer->work, msm_atomic_pending_work);
 150
 151         return 0;
 152 }
 153
 154 void msm_atomic_destroy_pending_timer(struct msm_pending_timer *timer)
 155 {
 156         if (timer->worker)
 157                 kthread_destroy_worker(timer->worker);
 158 }
 159
 160 static bool can_do_async(struct drm_atomic_state *state,
 161                 struct drm_crtc **async_crtc)
 162 {
 163         struct drm_connector_state *connector_state;
 164         struct drm_connector *connector;
 165         struct drm_crtc_state *crtc_state;
 166         struct drm_crtc *crtc;
 167         int i, num_crtcs = 0;
 168
 169         if (!(state->legacy_cursor_update || state->async_update))
 170                 return false;
 171
 172         /* any connector change, means slow path: */
 173         for_each_new_connector_in_state(state, connector, connector_state, i)
 174                 return false;
 175
 176         for_each_new_crtc_in_state(state, crtc, crtc_state, i) {
 177                 if (drm_atomic_crtc_needs_modeset(crtc_state))
 178                         return false;
 179                 if (++num_crtcs > 1)
 180                         return false;
 181                 *async_crtc = crtc;
 182         }
 183
 184         return true;
 185 }
 186
 187 /* Get bitmask of crtcs that will need to be flushed.  The bitmask
 188  * can be used with for_each_crtc_mask() iterator, to iterate
 189  * effected crtcs without needing to preserve the atomic state.
 190  */
 191 static unsigned get_crtc_mask(struct drm_atomic_state *state)
 192 {
 193         struct drm_crtc_state *crtc_state;
 194         struct drm_crtc *crtc;
 195         unsigned i, mask = 0;
 196
 197         for_each_new_crtc_in_state(state, crtc, crtc_state, i)
 198                 mask |= drm_crtc_mask(crtc);
 199
 200         return mask;
 201 }
 202
 203 void msm_atomic_commit_tail(struct drm_atomic_state *state)
 204 {
 205         struct drm_device *dev = state->dev;
 206         struct msm_drm_private *priv = dev->dev_private;
 207         struct msm_kms *kms = priv->kms;
 208         struct drm_crtc *async_crtc = NULL;
 209         unsigned crtc_mask = get_crtc_mask(state);
 210         bool async = kms->funcs->vsync_time &&
 211                         can_do_async(state, &async_crtc);
 212
 213         trace_msm_atomic_commit_tail_start(async, crtc_mask);
 214
 215         kms->funcs->enable_commit(kms);
 216
 217         /*
 218          * Ensure any previous (potentially async) commit has
 219          * completed:
 220          */
 221         lock_crtcs(kms, crtc_mask);
 222         trace_msm_atomic_wait_flush_start(crtc_mask);
 223         kms->funcs->wait_flush(kms, crtc_mask);
 224         trace_msm_atomic_wait_flush_finish(crtc_mask);
 225
 226         /*
 227          * Now that there is no in-progress flush, prepare the
 228          * current update:
 229          */
 230         kms->funcs->prepare_commit(kms, state);
 231
 232         /*
 233          * Push atomic updates down to hardware:
 234          */
 235         drm_atomic_helper_commit_modeset_disables(dev, state);
 236         drm_atomic_helper_commit_planes(dev, state, 0);
 237         drm_atomic_helper_commit_modeset_enables(dev, state);
 238
 239         if (async) {
 240                 struct msm_pending_timer *timer =
 241                         &kms->pending_timers[drm_crtc_index(async_crtc)];
 242
 243                 /* async updates are limited to single-crtc updates: */
 244                 WARN_ON(crtc_mask != drm_crtc_mask(async_crtc));
 245
 246                 /*
 247                  * Start timer if we don't already have an update pending
 248                  * on this crtc:
 249                  */
 250                 if (!(kms->pending_crtc_mask & crtc_mask)) {
 251                         ktime_t vsync_time, wakeup_time;
 252
 253                         kms->pending_crtc_mask |= crtc_mask;
 254
 255                         vsync_time = kms->funcs->vsync_time(kms, async_crtc);
 256                         wakeup_time = ktime_sub(vsync_time, ms_to_ktime(1));
 257
 258                         hrtimer_start(&timer->timer, wakeup_time,
 259                                         HRTIMER_MODE_ABS);
 260                 }
 261
 262                 kms->funcs->disable_commit(kms);
 263                 unlock_crtcs(kms, crtc_mask);
 264                 /*
 265                  * At this point, from drm core's perspective, we
 266                  * are done with the atomic update, so we can just
 267                  * go ahead and signal that it is done:
 268                  */
 269                 drm_atomic_helper_commit_hw_done(state);
 270                 drm_atomic_helper_cleanup_planes(dev, state);
 271
 272                 trace_msm_atomic_commit_tail_finish(async, crtc_mask);
 273
 274                 return;
 275         }
 276
 277         /*
 278          * If there is any async flush pending on updated crtcs, fold
 279          * them into the current flush.
 280          */
 281         kms->pending_crtc_mask &= ~crtc_mask;
 282
 283         vblank_get(kms, crtc_mask);
 284
 285         /*
 286          * Flush hardware updates:
 287          */
 288         trace_msm_atomic_flush_commit(crtc_mask);
 289         kms->funcs->flush_commit(kms, crtc_mask);
 290         unlock_crtcs(kms, crtc_mask);
 291         /*
 292          * Wait for flush to complete:
 293          */
 294         trace_msm_atomic_wait_flush_start(crtc_mask);
 295         kms->funcs->wait_flush(kms, crtc_mask);
 296         trace_msm_atomic_wait_flush_finish(crtc_mask);
 297
 298         vblank_put(kms, crtc_mask);
 299
 300         lock_crtcs(kms, crtc_mask);
 301         kms->funcs->complete_commit(kms, crtc_mask);
 302         unlock_crtcs(kms, crtc_mask);
 303         kms->funcs->disable_commit(kms);
 304
 305         drm_atomic_helper_commit_hw_done(state);
 306         drm_atomic_helper_cleanup_planes(dev, state);
 307
 308         trace_msm_atomic_commit_tail_finish(async, crtc_mask);
 309 }