From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> Currently we're failing to recalculate the gen9 FBC w/a stride unless something more drastic than just the modifier itself has changed. This often leaves us with FBC enabled with the linear fbdev framebuffer without the w/a stride enabled. That will cause an immediate underrun and FBC will get promptly disabled. Fix the problem by checking if the w/a stride is about to change, and go through the full dance if so. This part of the FBC code is still pretty much a disaster and will need lots more work. But this should at least fix the immediate issue. Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/display/intel_fbc.c | 29 ++++++++++++++++++------ 1 file changed, 22 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c index ef2eb14f6157..ff199374ed36 100644 --- a/drivers/gpu/drm/i915/display/intel_fbc.c +++ b/drivers/gpu/drm/i915/display/intel_fbc.c @@ -742,6 +742,25 @@ static bool intel_fbc_cfb_size_changed(struct drm_i915_private *dev_priv) fbc->compressed_fb.size * fbc->threshold; } +static u16 intel_fbc_gen9_wa_cfb_stride(struct drm_i915_private *dev_priv) +{ + struct intel_fbc *fbc = &dev_priv->fbc; + struct intel_fbc_state_cache *cache = &fbc->state_cache; + + if ((IS_GEN9_BC(dev_priv) || IS_BROXTON(dev_priv)) && + cache->fb.modifier != I915_FORMAT_MOD_X_TILED) + return DIV_ROUND_UP(cache->plane.src_w, 32 * fbc->threshold) * 8; + else + return 0; +} + +static bool intel_fbc_gen9_wa_cfb_stride_changed(struct drm_i915_private *dev_priv) +{ + struct intel_fbc *fbc = &dev_priv->fbc; + + return fbc->params.gen9_wa_cfb_stride != intel_fbc_gen9_wa_cfb_stride(dev_priv); +} + static bool intel_fbc_can_enable(struct drm_i915_private *dev_priv) { struct intel_fbc *fbc = &dev_priv->fbc; @@ -1218,7 +1237,8 @@ void intel_fbc_enable(struct intel_atomic_state *state, if (fbc->crtc) { if (fbc->crtc != crtc || - !intel_fbc_cfb_size_changed(dev_priv)) + (!intel_fbc_cfb_size_changed(dev_priv) && + !intel_fbc_gen9_wa_cfb_stride_changed(dev_priv))) goto out; __intel_fbc_disable(dev_priv); @@ -1240,12 +1260,7 @@ void intel_fbc_enable(struct intel_atomic_state *state, goto out; } - if ((IS_GEN9_BC(dev_priv) || IS_BROXTON(dev_priv)) && - plane_state->hw.fb->modifier != I915_FORMAT_MOD_X_TILED) - cache->gen9_wa_cfb_stride = - DIV_ROUND_UP(cache->plane.src_w, 32 * fbc->threshold) * 8; - else - cache->gen9_wa_cfb_stride = 0; + cache->gen9_wa_cfb_stride = intel_fbc_gen9_wa_cfb_stride(dev_priv); drm_dbg_kms(&dev_priv->drm, "Enabling FBC on pipe %c\n", pipe_name(crtc->pipe)); -- 2.26.2