Commit 074c3127 authored by Ville Syrjälä's avatar Ville Syrjälä
Browse files

drm/i915: Avoid triggering unwanted cdclk changes due to dbuf bandwidth changes 



Currently intel_bw_calc_min_cdclk() always adds the bw_state
to the atomic state. Not only does it result in potentially
redundant work later, it's also currently causing unwanted cdclk
changes during driver load.

Check if the dbuf bw is actually changing before we decide to
pull in the bw state.

Signed-off-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250326162544.3642-6-ville.syrjala@linux.intel.com


Reviewed-by: default avatarJani Nikula <jani.nikula@intel.com>
parent 18e68666

drivers/gpu/drm/i915/display/intel_bw.c

+13 −4
Original line number Diff line number Diff line
@@ -1294,7 +1294,8 @@ int intel_bw_calc_min_cdclk(struct intel_atomic_state *state, 
	struct intel_bw_state *new_bw_state = NULL;

	const struct intel_bw_state *old_bw_state = NULL;

	const struct intel_cdclk_state *cdclk_state;

	const struct intel_crtc_state *crtc_state;

	const struct intel_crtc_state *old_crtc_state;

	const struct intel_crtc_state *new_crtc_state;

	int old_min_cdclk, new_min_cdclk;

	struct intel_crtc *crtc;

	int i;
@@ -1302,15 +1303,23 @@ int intel_bw_calc_min_cdclk(struct intel_atomic_state *state, 
	if (DISPLAY_VER(display) < 9)

		return 0;



	for_each_new_intel_crtc_in_state(state, crtc, crtc_state, i) {

	for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state,

					    new_crtc_state, i) {

		struct intel_dbuf_bw old_dbuf_bw, new_dbuf_bw;



		skl_crtc_calc_dbuf_bw(&old_dbuf_bw, old_crtc_state);

		skl_crtc_calc_dbuf_bw(&new_dbuf_bw, new_crtc_state);



		if (!intel_dbuf_bw_changed(display, &old_dbuf_bw, &new_dbuf_bw))

			continue;



		new_bw_state = intel_atomic_get_bw_state(state);

		if (IS_ERR(new_bw_state))

			return PTR_ERR(new_bw_state);



		old_bw_state = intel_atomic_get_old_bw_state(state);



		skl_crtc_calc_dbuf_bw(&new_bw_state->dbuf_bw[crtc->pipe],

				      crtc_state);

		new_bw_state->dbuf_bw[crtc->pipe] = new_dbuf_bw;

	}



	if (!old_bw_state)