diff options
Diffstat (limited to 'drivers/gpu/drm/msm/msm_atomic.c')
| -rw-r--r-- | drivers/gpu/drm/msm/msm_atomic.c | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/drivers/gpu/drm/msm/msm_atomic.c b/drivers/gpu/drm/msm/msm_atomic.c new file mode 100644 index 000000000000..f0de412e13dc --- /dev/null +++ b/drivers/gpu/drm/msm/msm_atomic.c @@ -0,0 +1,163 @@ +/* + * Copyright (C) 2014 Red Hat + * Author: Rob Clark <robdclark@gmail.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include "msm_drv.h" +#include "msm_kms.h" +#include "msm_gem.h" + +struct msm_commit { + struct drm_atomic_state *state; + uint32_t fence; + struct msm_fence_cb fence_cb; +}; + +static void fence_cb(struct msm_fence_cb *cb); + +static struct msm_commit *new_commit(struct drm_atomic_state *state) +{ + struct msm_commit *c = kzalloc(sizeof(*c), GFP_KERNEL); + + if (!c) + return NULL; + + c->state = state; + /* TODO we might need a way to indicate to run the cb on a + * different wq so wait_for_vblanks() doesn't block retiring + * bo's.. + */ + INIT_FENCE_CB(&c->fence_cb, fence_cb); + + return c; +} + +/* The (potentially) asynchronous part of the commit. At this point + * nothing can fail short of armageddon. + */ +static void complete_commit(struct msm_commit *c) +{ + struct drm_atomic_state *state = c->state; + struct drm_device *dev = state->dev; + + drm_atomic_helper_commit_pre_planes(dev, state); + + drm_atomic_helper_commit_planes(dev, state); + + drm_atomic_helper_commit_post_planes(dev, state); + + drm_atomic_helper_wait_for_vblanks(dev, state); + + drm_atomic_helper_cleanup_planes(dev, state); + + drm_atomic_state_free(state); + + kfree(c); +} + +static void fence_cb(struct msm_fence_cb *cb) +{ + struct msm_commit *c = + container_of(cb, struct msm_commit, fence_cb); + complete_commit(c); +} + +static void add_fb(struct msm_commit *c, struct drm_framebuffer *fb) +{ + struct drm_gem_object *obj = msm_framebuffer_bo(fb, 0); + c->fence = max(c->fence, msm_gem_fence(to_msm_bo(obj), MSM_PREP_READ)); +} + + +/** + * drm_atomic_helper_commit - commit validated state object + * @dev: DRM device + * @state: the driver state object + * @async: asynchronous commit + * + * This function commits a with drm_atomic_helper_check() pre-validated state + * object. This can still fail when e.g. the framebuffer reservation fails. For + * now this doesn't implement asynchronous commits. + * + * RETURNS + * Zero for success or -errno. + */ +int msm_atomic_commit(struct drm_device *dev, + struct drm_atomic_state *state, bool async) +{ + struct msm_commit *c; + int nplanes = dev->mode_config.num_total_plane; + int i, ret; + + ret = drm_atomic_helper_prepare_planes(dev, state); + if (ret) + return ret; + + c = new_commit(state); + + /* + * Figure out what fence to wait for: + */ + for (i = 0; i < nplanes; i++) { + struct drm_plane *plane = state->planes[i]; + struct drm_plane_state *new_state = state->plane_states[i]; + + if (!plane) + continue; + + if ((plane->state->fb != new_state->fb) && new_state->fb) + add_fb(c, new_state->fb); + } + + /* + * This is the point of no return - everything below never fails except + * when the hw goes bonghits. Which means we can commit the new state on + * the software side now. + */ + + drm_atomic_helper_swap_state(dev, state); + + /* + * Everything below can be run asynchronously without the need to grab + * any modeset locks at all under one conditions: It must be guaranteed + * that the asynchronous work has either been cancelled (if the driver + * supports it, which at least requires that the framebuffers get + * cleaned up with drm_atomic_helper_cleanup_planes()) or completed + * before the new state gets committed on the software side with + * drm_atomic_helper_swap_state(). + * + * This scheme allows new atomic state updates to be prepared and + * checked in parallel to the asynchronous completion of the previous + * update. Which is important since compositors need to figure out the + * composition of the next frame right after having submitted the + * current layout. + */ + + if (async) { + msm_queue_fence_cb(dev, &c->fence_cb, c->fence); + return 0; + } + + ret = msm_wait_fence_interruptable(dev, c->fence, NULL); + if (ret) { + WARN_ON(ret); // TODO unswap state back? or?? + kfree(c); + return ret; + } + + complete_commit(c); + + return 0; +} |