On 2024-03-15 13:09, sunpeng.li@xxxxxxx wrote:
> From: Leo Li <sunpeng.li@xxxxxxx>
>
> [Why]
>
> DCN is the display hardware for amdgpu. DRM planes are backed by DCN
> hardware pipes, which carry pixel data from one end (memory), to the
> other (output encoder).
>
> Each DCN pipe has the ability to blend in a cursor early on in the
> pipeline. In other words, there are no dedicated cursor planes in DCN,
> which makes cursor behavior somewhat unintuitive for compositors.
>
> For example, if the cursor is in RGB format, but the top-most DRM plane
> is in YUV format, DCN will not be able to blend them. Because of this,
> amdgpu_dm rejects all configurations where a cursor needs to be enabled
> on top of a YUV formatted plane.
>
> From a compositor's perspective, when computing an allocation for
> hardware plane offloading, this cursor-on-yuv configuration result in an
> atomic test failure. Since the failure reason is not obvious at all,
> compositors will likely fall back to full rendering, which is not ideal.
>
> Instead, amdgpu_dm can try to accommodate the cursor-on-yuv
> configuration by opportunistically reserving a separate DCN pipe just
> for the cursor. We can refer to this as "overlay cursor mode". It is
> contrasted with "native cursor mode", where the native DCN per-pipe
> cursor is used.
>
> [How]
>
> On each crtc, compute whether the cursor plane should be enabled in
> overlay mode (which currently, is iff the immediate plane below has a
> YUV format). If it is, mark the CRTC as requesting overlay cursor mode.
>
> During DC validation, attempt to enable a separate DCN pipe for the
> cursor if it's in overlay mode. If that fails, or if no overlay mode is
> requested, then fallback to native mode.
>
> Signed-off-by: Leo Li <sunpeng.li@xxxxxxx>
We should run this through our usual testing cycle, and I need to go over
it a bit more closely than I have, but I like it, so it's
Acked-by: Harry Wentland <harry.wentland@xxxxxxx>
Harry
> ---
> .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 309 +++++++++++++++---
> .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h | 7 +
> .../amd/display/amdgpu_dm/amdgpu_dm_crtc.c | 1 +
> .../amd/display/amdgpu_dm/amdgpu_dm_plane.c | 13 +-
> 4 files changed, 288 insertions(+), 42 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index 21a61454c878..09ab330aed17 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -8359,8 +8359,19 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state,
> * Disable the cursor first if we're disabling all the planes.
> * It'll remain on the screen after the planes are re-enabled
> * if we don't.
> + *
> + * If the cursor is transitioning from native to overlay mode, the
> + * native cursor needs to be disabled first.
> */
> - if (acrtc_state->active_planes == 0)
> + if (acrtc_state->cursor_mode == DM_CURSOR_OVERLAY_MODE &&
> + dm_old_crtc_state->cursor_mode == DM_CURSOR_NATIVE_MODE) {
> + struct dc_cursor_position cursor_position = {0};
> + dc_stream_set_cursor_position(acrtc_state->stream,
> + &cursor_position);
> + }
> +
> + if (acrtc_state->active_planes == 0 &&
> + dm_old_crtc_state->cursor_mode == DM_CURSOR_NATIVE_MODE)
> amdgpu_dm_commit_cursors(state);
>
> /* update planes when needed */
> @@ -8374,7 +8385,8 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state,
> struct dm_plane_state *dm_new_plane_state = to_dm_plane_state(new_plane_state);
>
> /* Cursor plane is handled after stream updates */
> - if (plane->type == DRM_PLANE_TYPE_CURSOR) {
> + if (plane->type == DRM_PLANE_TYPE_CURSOR &&
> + acrtc_state->cursor_mode == DM_CURSOR_NATIVE_MODE) {
> if ((fb && crtc == pcrtc) ||
> (old_plane_state->fb && old_plane_state->crtc == pcrtc))
> cursor_update = true;
> @@ -8727,7 +8739,8 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state,
> * This avoids redundant programming in the case where we're going
> * to be disabling a single plane - those pipes are being disabled.
> */
> - if (acrtc_state->active_planes)
> + if (acrtc_state->active_planes &&
> + acrtc_state->cursor_mode == DM_CURSOR_NATIVE_MODE)
> amdgpu_dm_commit_cursors(state);
>
> cleanup:
> @@ -10039,7 +10052,8 @@ static bool should_reset_plane(struct drm_atomic_state *state,
> {
> struct drm_plane *other;
> struct drm_plane_state *old_other_state, *new_other_state;
> - struct drm_crtc_state *new_crtc_state;
> + struct drm_crtc_state *old_crtc_state, *new_crtc_state;
> + struct dm_crtc_state *old_dm_crtc_state, *new_dm_crtc_state;
> struct amdgpu_device *adev = drm_to_adev(plane->dev);
> int i;
>
> @@ -10061,10 +10075,24 @@ static bool should_reset_plane(struct drm_atomic_state *state,
>
> new_crtc_state =
> drm_atomic_get_new_crtc_state(state, new_plane_state->crtc);
> + old_crtc_state =
> + drm_atomic_get_old_crtc_state(state, old_plane_state->crtc);
>
> if (!new_crtc_state)
> return true;
>
> + /*
> + * A change in cursor mode means a new dc pipe needs to be acquired or
> + * released from the state
> + */
> + old_dm_crtc_state = to_dm_crtc_state(old_crtc_state);
> + new_dm_crtc_state = to_dm_crtc_state(new_crtc_state);
> + if (plane->type == DRM_PLANE_TYPE_CURSOR &&
> + old_dm_crtc_state != NULL &&
> + old_dm_crtc_state->cursor_mode != new_dm_crtc_state->cursor_mode) {
> + return true;
> + }
> +
> /* CRTC Degamma changes currently require us to recreate planes. */
> if (new_crtc_state->color_mgmt_changed)
> return true;
> @@ -10216,6 +10244,68 @@ static int dm_check_cursor_fb(struct amdgpu_crtc *new_acrtc,
> return 0;
> }
>
> +/*
> + * Helper function for checking the cursor in native mode
> + */
> +static int dm_check_native_cursor_state(struct drm_crtc *new_plane_crtc,
> + struct drm_plane *plane,
> + struct drm_plane_state *new_plane_state,
> + bool enable)
> +{
> +
> + struct amdgpu_crtc *new_acrtc;
> + int ret;
> +
> + if (!enable || !new_plane_crtc ||
> + drm_atomic_plane_disabling(plane->state, new_plane_state))
> + return 0;
> +
> + new_acrtc = to_amdgpu_crtc(new_plane_crtc);
> +
> + if (new_plane_state->src_x != 0 || new_plane_state->src_y != 0) {
> + DRM_DEBUG_ATOMIC("Cropping not supported for cursor plane\n");
> + return -EINVAL;
> + }
> +
> + if (new_plane_state->fb) {
> + ret = dm_check_cursor_fb(new_acrtc, new_plane_state,
> + new_plane_state->fb);
> + if (ret)
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static bool dm_should_update_native_cursor(struct drm_atomic_state *state,
> + struct drm_crtc *old_plane_crtc,
> + struct drm_crtc *new_plane_crtc,
> + bool enable)
> +{
> + struct drm_crtc_state *old_crtc_state, *new_crtc_state;
> + struct dm_crtc_state *dm_old_crtc_state, *dm_new_crtc_state;
> +
> + if (!enable) {
> + if (old_plane_crtc == NULL)
> + return true;
> +
> + old_crtc_state = drm_atomic_get_old_crtc_state(
> + state, old_plane_crtc);
> + dm_old_crtc_state = to_dm_crtc_state(old_crtc_state);
> +
> + return dm_old_crtc_state->cursor_mode == DM_CURSOR_NATIVE_MODE;
> + } else {
> + if (new_plane_crtc == NULL)
> + return true;
> +
> + new_crtc_state = drm_atomic_get_new_crtc_state(
> + state, new_plane_crtc);
> + dm_new_crtc_state = to_dm_crtc_state(new_crtc_state);
> +
> + return dm_new_crtc_state->cursor_mode == DM_CURSOR_NATIVE_MODE;
> + }
> +}
> +
> static int dm_update_plane_state(struct dc *dc,
> struct drm_atomic_state *state,
> struct drm_plane *plane,
> @@ -10231,8 +10321,7 @@ static int dm_update_plane_state(struct dc *dc,
> struct drm_crtc_state *old_crtc_state, *new_crtc_state;
> struct dm_crtc_state *dm_new_crtc_state, *dm_old_crtc_state;
> struct dm_plane_state *dm_new_plane_state, *dm_old_plane_state;
> - struct amdgpu_crtc *new_acrtc;
> - bool needs_reset;
> + bool needs_reset, update_native_cursor;
> int ret = 0;
>
>
> @@ -10241,24 +10330,16 @@ static int dm_update_plane_state(struct dc *dc,
> dm_new_plane_state = to_dm_plane_state(new_plane_state);
> dm_old_plane_state = to_dm_plane_state(old_plane_state);
>
> - if (plane->type == DRM_PLANE_TYPE_CURSOR) {
> - if (!enable || !new_plane_crtc ||
> - drm_atomic_plane_disabling(plane->state, new_plane_state))
> - return 0;
> -
> - new_acrtc = to_amdgpu_crtc(new_plane_crtc);
> -
> - if (new_plane_state->src_x != 0 || new_plane_state->src_y != 0) {
> - DRM_DEBUG_ATOMIC("Cropping not supported for cursor plane\n");
> - return -EINVAL;
> - }
> + update_native_cursor = dm_should_update_native_cursor(state,
> + old_plane_crtc,
> + new_plane_crtc,
> + enable);
>
> - if (new_plane_state->fb) {
> - ret = dm_check_cursor_fb(new_acrtc, new_plane_state,
> - new_plane_state->fb);
> - if (ret)
> - return ret;
> - }
> + if (plane->type == DRM_PLANE_TYPE_CURSOR && update_native_cursor) {
> + ret = dm_check_native_cursor_state(new_plane_crtc, plane,
> + new_plane_state, enable);
> + if (ret)
> + return ret;
>
> return 0;
> }
> @@ -10285,16 +10366,17 @@ static int dm_update_plane_state(struct dc *dc,
> plane->base.id, old_plane_crtc->base.id);
>
> ret = dm_atomic_get_state(state, &dm_state);
> - if (ret)
> - return ret;
> + if (ret) {
> + goto out;
> + }
>
> if (!dc_state_remove_plane(
> dc,
> dm_old_crtc_state->stream,
> dm_old_plane_state->dc_state,
> dm_state->context)) {
> -
> - return -EINVAL;
> + ret = -EINVAL;
> + goto out;
> }
>
> if (dm_old_plane_state->dc_state)
> @@ -10323,21 +10405,16 @@ static int dm_update_plane_state(struct dc *dc,
> return 0;
>
> ret = amdgpu_dm_plane_helper_check_state(new_plane_state, new_crtc_state);
> - if (ret)
> - return ret;
> + if (ret) {
> + goto out;
> + }
>
> WARN_ON(dm_new_plane_state->dc_state);
>
> dc_new_plane_state = dc_create_plane_state(dc);
> - if (!dc_new_plane_state)
> - return -ENOMEM;
> -
> - /* Block top most plane from being a video plane */
> - if (plane->type == DRM_PLANE_TYPE_OVERLAY) {
> - if (amdgpu_dm_plane_is_video_format(new_plane_state->fb->format->format) && *is_top_most_overlay)
> - return -EINVAL;
> -
> - *is_top_most_overlay = false;
> + if (!dc_new_plane_state) {
> + ret = -ENOMEM;
> + goto out;
> }
>
> DRM_DEBUG_ATOMIC("Enabling DRM plane: %d on DRM crtc %d\n",
> @@ -10350,13 +10427,13 @@ static int dm_update_plane_state(struct dc *dc,
> new_crtc_state);
> if (ret) {
> dc_plane_state_release(dc_new_plane_state);
> - return ret;
> + goto out;
> }
>
> ret = dm_atomic_get_state(state, &dm_state);
> if (ret) {
> dc_plane_state_release(dc_new_plane_state);
> - return ret;
> + goto out;
> }
>
> /*
> @@ -10373,7 +10450,8 @@ static int dm_update_plane_state(struct dc *dc,
> dm_state->context)) {
>
> dc_plane_state_release(dc_new_plane_state);
> - return -EINVAL;
> + ret = -EINVAL;
> + goto out;
> }
>
> dm_new_plane_state->dc_state = dc_new_plane_state;
> @@ -10388,6 +10466,16 @@ static int dm_update_plane_state(struct dc *dc,
> *lock_and_validation_needed = true;
> }
>
> +out:
> + /* If cursor overlay failed, attempt fallback to native mode */
> + if (ret == -EINVAL && plane->type == DRM_PLANE_TYPE_CURSOR) {
> + ret = dm_check_native_cursor_state(new_plane_crtc, plane,
> + new_plane_state, enable);
> + if (ret) {
> + return ret;
> + }
> + dm_new_crtc_state->cursor_mode = DM_CURSOR_NATIVE_MODE;
> + }
>
> return ret;
> }
> @@ -10544,6 +10632,126 @@ static int add_affected_mst_dsc_crtcs(struct drm_atomic_state *state, struct drm
> return drm_dp_mst_add_affected_dsc_crtcs(state, &aconnector->mst_root->mst_mgr);
> }
>
> +/**
> + * DOC: Cursor Modes - Native vs Overlay
> + *
> + * In native mode, the cursor uses a integrated cursor pipe within each DCN hw
> + * plane. It does not require a dedicated hw plane to enable, but it is
> + * subjected to the same z-order and scaling as the hw plane. It also has format
> + * restrictions, a RGB cursor in native mode cannot be enabled within a non-RGB
> + * hw plane.
> + *
> + * In overlay mode, the cursor uses a separate DCN hw plane, and thus has its
> + * own scaling and z-pos. It also has no blending restrictions. It lends to a
> + * cursor behavior more akin to a DRM client's expectations. However, it does
> + * occupy an extra DCN plane, and therefore will only be used if a DCN plane is
> + * available.
> +*/
> +
> +/**
> + * Set whether the cursor should be enabled in native mode, or overlay mode, on
> + * the dm_crtc_state.
> + *
> + * The cursor should be enabled in overlay mode if the immediate underlying
> + * plane contains a video format.
> + *
> + * Since zpos info is required, drm_atomic_normalize_zpos must be called before
> + * calling this function.
> +*/
> +static int dm_crtc_set_cursor_mode(struct drm_atomic_state *state,
> + struct dm_crtc_state *dm_crtc_state)
> +{
> + struct drm_plane_state *plane_state, *old_plane_state, *target_plane_state;
> + struct drm_crtc_state *crtc_state = &dm_crtc_state->base;
> + struct drm_plane *plane;
> + bool consider_mode_change = false;
> + bool cursor_changed = false;
> + unsigned int target_zpos;
> + unsigned int cursor_zpos;
> + int i;
> +
> + /*
> + * Cursor mode can change if a plane's format changes, is
> + * enabled/disabled, or z-order changes.
> + */
> + for_each_oldnew_plane_in_state(state, plane, old_plane_state, plane_state, i) {
> +
> + /* Only care about planes on this CRTC */
> + if ((drm_plane_mask(plane) & crtc_state->plane_mask) == 0)
> + continue;
> +
> + if (plane->type == DRM_PLANE_TYPE_CURSOR)
> + cursor_changed = true;
> +
> + if (drm_atomic_plane_enabling(old_plane_state, plane_state) ||
> + drm_atomic_plane_disabling(old_plane_state, plane_state) ||
> + old_plane_state->fb->format != plane_state->fb->format) {
> + consider_mode_change = true;
> + break;
> + }
> + }
> +
> + if (!consider_mode_change && !crtc_state->zpos_changed) {
> + return 0;
> + }
> +
> + /*
> + * If no cursor change on this CRTC, and not enabled on this CRTC, then
> + * no need to set cursor mode. This avoids needlessly locking the cursor
> + * state.
> + */
> + if (!cursor_changed &&
> + !(drm_plane_mask(crtc_state->crtc->cursor) & crtc_state->plane_mask)) {
> + return 0;
> + }
> +
> + plane_state = drm_atomic_get_plane_state(state,
> + crtc_state->crtc->cursor);
> + if (IS_ERR(plane_state))
> + return PTR_ERR(plane_state);
> +
> + /* Cursor is disabled */
> + if (!plane_state->fb)
> + return 0;
> +
> + cursor_zpos = plane_state->normalized_zpos;
> +
> + /* Get enabled plane immediately below cursor. */
> + target_plane_state = NULL;
> + target_zpos = 0;
> + drm_for_each_plane_mask(plane, state->dev, crtc_state->plane_mask) {
> + if (plane->type == DRM_PLANE_TYPE_CURSOR)
> + continue;
> +
> + plane_state = drm_atomic_get_plane_state(state, plane);
> + if (IS_ERR(plane_state))
> + return PTR_ERR(plane_state);
> +
> + if (!plane_state->fb ||
> + plane_state->normalized_zpos >= cursor_zpos)
> + continue;
> +
> + if (plane_state->normalized_zpos >= target_zpos) {
> + target_zpos = plane_state->normalized_zpos;
> + target_plane_state = plane_state;
> + }
> + }
> +
> + /* Nothing below cursor - use overlay mode */
> + if (target_plane_state == NULL) {
> + dm_crtc_state->cursor_mode = DM_CURSOR_OVERLAY_MODE;
> + return 0;
> + }
> +
> + if (amdgpu_dm_plane_is_video_format(target_plane_state->fb->format->format)) {
> + dm_crtc_state->cursor_mode = DM_CURSOR_OVERLAY_MODE;
> + } else {
> + dm_crtc_state->cursor_mode = DM_CURSOR_NATIVE_MODE;
> + }
> +
> + return 0;
> +}
> +
> /**
> * amdgpu_dm_atomic_check() - Atomic check implementation for AMDgpu DM.
> *
> @@ -10713,6 +10921,20 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
> goto fail;
> }
>
> + /*
> + * Determine whether cursors on each CRTC should be enabled in native or
> + * overlay mode.
> + */
> + for_each_new_crtc_in_state(state, crtc, new_crtc_state, i) {
> + dm_new_crtc_state = to_dm_crtc_state(new_crtc_state);
> +
> + ret = dm_crtc_set_cursor_mode(state, dm_new_crtc_state);
> + if (ret) {
> + drm_dbg(dev, "Failed to determine cursor mode\n");
> + goto fail;
> + }
> + }
> +
> /* Remove exiting planes if they are modified */
> for_each_oldnew_plane_in_state_reverse(state, plane, old_plane_state, new_plane_state, i) {
> if (old_plane_state->fb && new_plane_state->fb &&
> @@ -10793,6 +11015,11 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
>
> /* Check cursor planes scaling */
> for_each_new_crtc_in_state(state, crtc, new_crtc_state, i) {
> + /* Overlay cusor does not need scaling check */
> + dm_new_crtc_state = to_dm_crtc_state(new_crtc_state);
> + if (dm_new_crtc_state->cursor_mode == DM_CURSOR_OVERLAY_MODE)
> + continue;
> +
> ret = dm_check_crtc_cursor(state, crtc, new_crtc_state);
> if (ret) {
> DRM_DEBUG_DRIVER("dm_check_crtc_cursor() failed\n");
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
> index 09519b7abf67..b8d39fdd1e09 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
> @@ -822,6 +822,11 @@ struct dm_plane_state {
> enum amdgpu_transfer_function blend_tf;
> };
>
> +enum amdgpu_dm_cursor_mode {
> + DM_CURSOR_NATIVE_MODE = 0,
> + DM_CURSOR_OVERLAY_MODE,
> +};
> +
> struct dm_crtc_state {
> struct drm_crtc_state base;
> struct dc_stream_state *stream;
> @@ -852,6 +857,8 @@ struct dm_crtc_state {
> * encoding.
> */
> enum amdgpu_transfer_function regamma_tf;
> +
> + enum amdgpu_dm_cursor_mode cursor_mode;
> };
>
> #define to_dm_crtc_state(x) container_of(x, struct dm_crtc_state, base)
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
> index e23a0a276e33..67aea1d2feb9 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
> @@ -304,6 +304,7 @@ static struct drm_crtc_state *amdgpu_dm_crtc_duplicate_state(struct drm_crtc *cr
> state->regamma_tf = cur->regamma_tf;
> state->crc_skip_count = cur->crc_skip_count;
> state->mpo_requested = cur->mpo_requested;
> + state->cursor_mode = cur->cursor_mode;
> /* TODO Duplicate dc_stream after objects are stream object is flattened */
>
> return &state->base;
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c
> index 8a4c40b4c27e..ed1fc01f1649 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c
> @@ -104,7 +104,7 @@ void amdgpu_dm_plane_fill_blending_from_plane_state(const struct drm_plane_state
> *global_alpha = false;
> *global_alpha_value = 0xff;
>
> - if (plane_state->plane->type != DRM_PLANE_TYPE_OVERLAY)
> + if (plane_state->plane->type == DRM_PLANE_TYPE_PRIMARY)
> return;
>
> if (plane_state->pixel_blend_mode == DRM_MODE_BLEND_PREMULTI ||
> @@ -1175,10 +1175,21 @@ static int amdgpu_dm_plane_atomic_check(struct drm_plane *plane,
> static int amdgpu_dm_plane_atomic_async_check(struct drm_plane *plane,
> struct drm_atomic_state *state)
> {
> + struct drm_crtc_state *new_crtc_state;
> + struct drm_plane_state *new_plane_state;
> + struct dm_crtc_state *dm_new_crtc_state;
> +
> /* Only support async updates on cursor planes. */
> if (plane->type != DRM_PLANE_TYPE_CURSOR)
> return -EINVAL;
>
> + new_plane_state = drm_atomic_get_new_plane_state(state, plane);
> + new_crtc_state = drm_atomic_get_new_crtc_state(state, new_plane_state->crtc);
> + dm_new_crtc_state = to_dm_crtc_state(new_crtc_state);
> + /* Reject overlay cursors for now*/
> + if (dm_new_crtc_state->cursor_mode == DM_CURSOR_OVERLAY_MODE)
> + return -EINVAL;
> +
> return 0;
> }
>
