Commit a582354c authored by Ville Syrjälä's avatar Ville Syrjälä Committed by Manasi Navare

drm/i915: Pimp the watermark documentation a bit

Document what each of the "raw" vs. "optimal" vs. "intermediate"
watermarks do.
Signed-off-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: default avatarManasi Navare <manasi.d.navare@intel.com>
Signed-off-by: default avatarManasi Navare <manasi.d.navare@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201106173042.7534-4-ville.syrjala@linux.intel.com
parent dbf71381
......@@ -737,25 +737,34 @@ struct g4x_wm_state {
struct intel_crtc_wm_state {
union {
/*
* raw:
* The "raw" watermark values produced by the formula
* given the plane's current state. They do not consider
* how much FIFO is actually allocated for each plane.
*
* optimal:
* The "optimal" watermark values given the current
* state of the planes and the amount of FIFO
* allocated to each, ignoring any previous state
* of the planes.
*
* intermediate:
* The "intermediate" watermark values when transitioning
* between the old and new "optimal" values. Used when
* the watermark registers are single buffered and hence
* their state changes asynchronously with regards to the
* actual plane registers. These are essentially the
* worst case combination of the old and new "optimal"
* watermarks, which are therefore safe to use when the
* plane is in either its old or new state.
*/
struct {
/*
* Intermediate watermarks; these can be
* programmed immediately since they satisfy
* both the current configuration we're
* switching away from and the new
* configuration we're switching to.
*/
struct intel_pipe_wm intermediate;
/*
* Optimal watermarks, programmed post-vblank
* when this state is committed.
*/
struct intel_pipe_wm optimal;
} ilk;
struct {
/* "raw" watermarks */
struct skl_pipe_wm raw;
/* gen9+ only needs 1-step wm programming */
struct skl_pipe_wm optimal;
......@@ -765,22 +774,15 @@ struct intel_crtc_wm_state {
} skl;
struct {
/* "raw" watermarks (not inverted) */
struct g4x_pipe_wm raw[NUM_VLV_WM_LEVELS];
/* intermediate watermarks (inverted) */
struct vlv_wm_state intermediate;
/* optimal watermarks (inverted) */
struct vlv_wm_state optimal;
/* display FIFO split */
struct g4x_pipe_wm raw[NUM_VLV_WM_LEVELS]; /* not inverted */
struct vlv_wm_state intermediate; /* inverted */
struct vlv_wm_state optimal; /* inverted */
struct vlv_fifo_state fifo_state;
} vlv;
struct {
/* "raw" watermarks */
struct g4x_pipe_wm raw[NUM_G4X_WM_LEVELS];
/* intermediate watermarks */
struct g4x_wm_state intermediate;
/* optimal watermarks */
struct g4x_wm_state optimal;
} g4x;
};
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment