[PATCH v2 08/13] drm/i915: Use intel_dsb_supported() to determine 'use_dsb'

[Ville Syrjala <ville.syrjala@linux.intel.com>]

From: Ville Syrjälä <ville.syrjala@linux.intel.com>

Currently we calculate crtc_state->use_dsb by simply assuming
that DSB is available, and then falling back to MMIO when the
actual DSB buffer allocation fails.

This is somewhat confusing, and doesn't match how the flip queue
counterpart (use_flipq) is calculated.  Check whether DSB is
available ahead of time, just like we in the flip queue case.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_display.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index fc30a455bed3..7741f1395375 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -7392,6 +7392,7 @@ static void intel_atomic_dsb_prepare(struct intel_atomic_state *state,
 		!intel_crtc_needs_color_update(new_crtc_state);
 
 	new_crtc_state->use_dsb =
+		intel_dsb_supported(display) &&
 		!new_crtc_state->use_flipq &&
 		!new_crtc_state->do_async_flip &&
 		(DISPLAY_VER(display) >= 20 || !new_crtc_state->has_psr) &&
-- 
2.54.0