From 074c31271a1d9ec74c5a1965589671337be11d0f Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Wed, 26 Mar 2025 18:25:35 +0200 Subject: [PATCH] drm/i915: Avoid triggering unwanted cdclk changes due to dbuf bandwidth changes MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20250326162544.3642-6-ville.syrjala@linux.intel.com Reviewed-by: Jani Nikula --- drivers/gpu/drm/i915/display/intel_bw.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_bw.c b/drivers/gpu/drm/i915/display/intel_bw.c index 67d088da1f38..19b516084fac 100644 --- a/drivers/gpu/drm/i915/display/intel_bw.c +++ b/drivers/gpu/drm/i915/display/intel_bw.c @@ -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) -- 2.50.1