drm/i915/display: Configure the second scaler

Both sharpness and panel fitter use pipe scaler,
but only one can be enabled at a time. Furthermore
sharpness uses second scaler. So for CASF, check if
second scaler is available and make sure that only
either of panel fitter or sharpness is enabled at
a time.

v2: Add the panel fitting check before enabling sharpness
v3: Reframe commit message[Arun]
v4: Replace string based comparison with plane_state[Jani]
v5: Rebase
v6: Fix build issue
v7: Remove scaler id from verify_crtc_state[Ankit]
v8: Change the patch title. Add code comment.
    Move the config part in patch#6. [Ankit]
v9: Refactor the patch[Ankit]
v10: Modify the header of patch[Ankit]

Signed-off-by: Nemesa Garg <nemesa.garg@intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://patch.msgid.link/20251028120747.3027332-8-ankit.k.nautiyal@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

1 files changed, 19 insertions, 6 deletions

diff --git a/drivers/gpu/drm/i915/display/skl_scaler.c b/drivers/gpu/drm/i915/display/skl_scaler.c
index dbb810c0474c..9439b1a65fa6 100644
--- a/drivers/gpu/drm/i915/display/skl_scaler.c
+++ b/drivers/gpu/drm/i915/display/skl_scaler.c
@@ -6,6 +6,7 @@
 #include <drm/drm_print.h>
 
 #include "i915_utils.h"
+#include "intel_casf.h"
 #include "intel_casf_regs.h"
 #include "intel_de.h"
 #include "intel_display_regs.h"
@@ -283,7 +284,8 @@ int skl_update_scaler_crtc(struct intel_crtc_state *crtc_state)
 				 drm_rect_width(&crtc_state->pipe_src),
 				 drm_rect_height(&crtc_state->pipe_src),
 				 width, height, NULL, 0,
-				 crtc_state->pch_pfit.enabled);
+				 crtc_state->pch_pfit.enabled ||
+				 intel_casf_needs_scaler(crtc_state));
 }
 
 /**
@@ -322,7 +324,9 @@ int skl_update_scaler_plane(struct intel_crtc_state *crtc_state,
 }
 
 static int intel_allocate_scaler(struct intel_crtc_scaler_state *scaler_state,
-				 struct intel_crtc *crtc)
+				 struct intel_crtc *crtc,
+				 struct intel_plane_state *plane_state,
+				 bool casf_scaler)
 {
 	int i;
 
@@ -330,6 +334,10 @@ static int intel_allocate_scaler(struct intel_crtc_scaler_state *scaler_state,
 		if (scaler_state->scalers[i].in_use)
 			continue;
 
+		/* CASF needs second scaler */
+		if (!plane_state && casf_scaler && i != 1)
+			continue;
+
 		scaler_state->scalers[i].in_use = true;
 
 		return i;
@@ -380,7 +388,7 @@ static int intel_atomic_setup_scaler(struct intel_crtc_state *crtc_state,
 				     int num_scalers_need, struct intel_crtc *crtc,
 				     const char *name, int idx,
 				     struct intel_plane_state *plane_state,
-				     int *scaler_id)
+				     int *scaler_id, bool casf_scaler)
 {
 	struct intel_display *display = to_intel_display(crtc);
 	struct intel_crtc_scaler_state *scaler_state = &crtc_state->scaler_state;
@@ -389,7 +397,7 @@ static int intel_atomic_setup_scaler(struct intel_crtc_state *crtc_state,
 	int vscale = 0;
 
 	if (*scaler_id < 0)
-		*scaler_id = intel_allocate_scaler(scaler_state, crtc);
+		*scaler_id = intel_allocate_scaler(scaler_state, crtc, plane_state, casf_scaler);
 
 	if (drm_WARN(display->drm, *scaler_id < 0,
 		     "Cannot find scaler for %s:%d\n", name, idx))
@@ -521,10 +529,14 @@ static int setup_crtc_scaler(struct intel_atomic_state *state,
 	struct intel_crtc_scaler_state *scaler_state =
 		&crtc_state->scaler_state;
 
+	if (intel_casf_needs_scaler(crtc_state) && crtc_state->pch_pfit.enabled)
+		return -EINVAL;
+
 	return intel_atomic_setup_scaler(crtc_state,
 					 hweight32(scaler_state->scaler_users),
 					 crtc, "CRTC", crtc->base.base.id,
-					 NULL, &scaler_state->scaler_id);
+					 NULL, &scaler_state->scaler_id,
+					 intel_casf_needs_scaler(crtc_state));
 }
 
 static int setup_plane_scaler(struct intel_atomic_state *state,
@@ -559,7 +571,8 @@ static int setup_plane_scaler(struct intel_atomic_state *state,
 	return intel_atomic_setup_scaler(crtc_state,
 					 hweight32(scaler_state->scaler_users),
 					 crtc, "PLANE", plane->base.base.id,
-					 plane_state, &plane_state->scaler_id);
+					 plane_state, &plane_state->scaler_id,
+					 false);
 }
 
 /**