... and use it in msm&vc4. Again just want to encapsulate drm_atomic_state internals a bit.
The const threading is a bit awkward in vc4 since C sucks, but I still think it's worth to enforce this. Eventually I want to make all the obj->state pointers const too, but that's a lot more work ... Cc: Eric Anholt <eric at anholt.net> Cc: Rob Clark <robdclark at gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter at intel.com> --- drivers/gpu/drm/msm/mdp/mdp5/mdp5_crtc.c | 10 +++------ drivers/gpu/drm/vc4/vc4_crtc.c | 11 +++------- drivers/gpu/drm/vc4/vc4_drv.h | 2 +- drivers/gpu/drm/vc4/vc4_plane.c | 5 +++-- include/drm/drm_atomic.h | 36 ++++++++++++++++++++++++++++++++ 5 files changed, 46 insertions(+), 18 deletions(-) diff --git a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_crtc.c b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_crtc.c index 88fe256c1931..6d4086ee0503 100644 --- a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_crtc.c +++ b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_crtc.c @@ -383,19 +383,15 @@ static int mdp5_crtc_atomic_check(struct drm_crtc *crtc, */ hw_cfg = mdp5_cfg_get_hw_config(mdp5_kms->cfg); drm_atomic_crtc_state_for_each_plane(plane, state) { - struct drm_plane_state *pstate; + const struct drm_plane_state *pstate; if (cnt >= (hw_cfg->lm.nb_stages)) { dev_err(dev->dev, "too many planes!\n"); return -EINVAL; } - pstate = state->state->plane_states[drm_plane_index(plane)]; + pstate = __drm_atomic_get_current_plane_state(state->state, + plane); - /* plane might not have changed, in which case take - * current state: - */ - if (!pstate) - pstate = plane->state; pstates[cnt].plane = plane; pstates[cnt].state = to_mdp5_plane_state(pstate); diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c index 904d0754ad78..703bda170105 100644 --- a/drivers/gpu/drm/vc4/vc4_crtc.c +++ b/drivers/gpu/drm/vc4/vc4_crtc.c @@ -405,14 +405,9 @@ static int vc4_crtc_atomic_check(struct drm_crtc *crtc, return -EINVAL; drm_atomic_crtc_state_for_each_plane(plane, state) { - struct drm_plane_state *plane_state = - state->state->plane_states[drm_plane_index(plane)]; - - /* plane might not have changed, in which case take - * current state: - */ - if (!plane_state) - plane_state = plane->state; + const struct drm_plane_state *plane_state = + __drm_atomic_get_current_plane_state(state->state, + plane); dlist_count += vc4_plane_dlist_size(plane_state); } diff --git a/drivers/gpu/drm/vc4/vc4_drv.h b/drivers/gpu/drm/vc4/vc4_drv.h index 37cac59401d7..c799baabc008 100644 --- a/drivers/gpu/drm/vc4/vc4_drv.h +++ b/drivers/gpu/drm/vc4/vc4_drv.h @@ -469,7 +469,7 @@ int vc4_kms_load(struct drm_device *dev); struct drm_plane *vc4_plane_init(struct drm_device *dev, enum drm_plane_type type); u32 vc4_plane_write_dlist(struct drm_plane *plane, u32 __iomem *dlist); -u32 vc4_plane_dlist_size(struct drm_plane_state *state); +u32 vc4_plane_dlist_size(const struct drm_plane_state *state); void vc4_plane_async_set_fb(struct drm_plane *plane, struct drm_framebuffer *fb); diff --git a/drivers/gpu/drm/vc4/vc4_plane.c b/drivers/gpu/drm/vc4/vc4_plane.c index 4037b52fde31..5d2c3d9fd17a 100644 --- a/drivers/gpu/drm/vc4/vc4_plane.c +++ b/drivers/gpu/drm/vc4/vc4_plane.c @@ -690,9 +690,10 @@ u32 vc4_plane_write_dlist(struct drm_plane *plane, u32 __iomem *dlist) return vc4_state->dlist_count; } -u32 vc4_plane_dlist_size(struct drm_plane_state *state) +u32 vc4_plane_dlist_size(const struct drm_plane_state *state) { - struct vc4_plane_state *vc4_state = to_vc4_plane_state(state); + const struct vc4_plane_state *vc4_state = + container_of(state, typeof(*vc4_state), base); return vc4_state->dlist_count; } diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h index 92c84e9ab09a..4e97186293be 100644 --- a/include/drm/drm_atomic.h +++ b/include/drm/drm_atomic.h @@ -109,6 +109,42 @@ drm_atomic_get_existing_connector_state(struct drm_atomic_state *state, return state->connector_states[index]; } +/** + * __drm_atomic_get_current_plane_state - get current plane state + * @state: global atomic state object + * @plane: plane to grab + * + * This function returns the plane state for the given plane, either from + * @state, or if the plane isn't part of the atomic state update, from @plane. + * This is useful in atomic check callbacks, when drivers need to peek at, but + * not change, state of other planes, since it avoids threading an error code + * back up the call chain. + * + * WARNING: + * + * Note that this function is in general unsafe since it doesn't check for the + * required locking for access state structures. Drivers must ensure that it is + * save to access the returned state structure through other means. One commone + * example is when planes are fixed to a single CRTC, and the driver knows that + * the CRTC locks is held already. In that case holding the CRTC locks gives a + * read-lock on all planes connected to that CRTC. But if planes can be + * reassigned things get more tricky. In that case it's better to use + * drm_atomic_get_plane_state and wire up full error handling. + * + * Returns: + * + * Read-only pointer to the current plane state. + */ +static inline const struct drm_plane_state * +__drm_atomic_get_current_plane_state(struct drm_atomic_state *state, + struct drm_plane *plane) +{ + if (state->plane_states[drm_plane_index(plane)]) + return state->plane_states[drm_plane_index(plane)]; + + return plane->state; +} + int __must_check drm_atomic_set_mode_for_crtc(struct drm_crtc_state *state, struct drm_display_mode *mode); -- 2.8.1