[PATCH 10/10] drm/i915/vrr: Always use VRR timing generator for XELPD+

[Ankit Nautiyal]

Currently VRR timing generator is used only when VRR is enabled by
userspace. From XELPD+, gradually move away from older timing
generator and use VRR timing generator for fixed refresh rate also.
In such a case, Flipline VMin and VMax all are set to the Vtotal of the
mode, which effectively makes the VRR timing generator work in
fixed refresh rate mode.

v2: Use VRR Timing Generator from XELPD+ instead of MTL as it needs
Wa_14015406119.

v3: Set vrr.fixed during vrr_get_config (Mitul)

Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
---
 drivers/gpu/drm/i915/display/intel_vrr.c | 63 +++++++++++++++---------
 1 file changed, 41 insertions(+), 22 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c b/drivers/gpu/drm/i915/display/intel_vrr.c
index 50ac2770a42d..ef965c273a9e 100644
--- a/drivers/gpu/drm/i915/display/intel_vrr.c
+++ b/drivers/gpu/drm/i915/display/intel_vrr.c
@@ -174,41 +174,56 @@ intel_vrr_compute_config(struct intel_crtc_state *crtc_state,
 	if (adjusted_mode->flags & DRM_MODE_FLAG_INTERLACE)
 		return;
 
-	crtc_state->vrr.in_range =
-		intel_vrr_is_in_range(connector, drm_mode_vrefresh(adjusted_mode));
-	if (!crtc_state->vrr.in_range)
-		return;
-
 	if (HAS_LRR(i915))
 		crtc_state->update_lrr = true;
 
-	vmin = DIV_ROUND_UP(adjusted_mode->crtc_clock * 1000,
-			    adjusted_mode->crtc_htotal * info->monitor_range.max_vfreq);
-	vmax = adjusted_mode->crtc_clock * 1000 /
-		(adjusted_mode->crtc_htotal * info->monitor_range.min_vfreq);
+	if (!crtc_state->uapi.vrr_enabled && DISPLAY_VER(i915) >= 20) {
+		/*
+		 * for XELPD+ always go for VRR timing generator even for
+		 * fixed refresh rate.
+		 */
+		crtc_state->vrr.vmin = adjusted_mode->crtc_vtotal;
+		crtc_state->vrr.vmax = adjusted_mode->crtc_vtotal;
+		crtc_state->vrr.flipline = adjusted_mode->crtc_vtotal;
+		crtc_state->vrr.fixed_rr = true;
+	} else {
 
-	vmin = max_t(int, vmin, adjusted_mode->crtc_vtotal);
-	vmax = max_t(int, vmax, adjusted_mode->crtc_vtotal);
+		crtc_state->vrr.in_range =
+			intel_vrr_is_in_range(connector, drm_mode_vrefresh(adjusted_mode));
 
-	if (vmin >= vmax)
-		return;
+		if (!crtc_state->vrr.in_range)
+			return;
 
-	/*
-	 * flipline determines the min vblank length the hardware will
-	 * generate, and flipline>=vmin+1, hence we reduce vmin by one
-	 * to make sure we can get the actual min vblank length.
-	 */
-	crtc_state->vrr.vmin = vmin - 1;
-	crtc_state->vrr.vmax = vmax;
 
-	crtc_state->vrr.flipline = crtc_state->vrr.vmin + 1;
+		vmin = DIV_ROUND_UP(adjusted_mode->crtc_clock * 1000,
+				    adjusted_mode->crtc_htotal * info->monitor_range.max_vfreq);
+		vmax = adjusted_mode->crtc_clock * 1000 /
+			(adjusted_mode->crtc_htotal * info->monitor_range.min_vfreq);
+
+		vmin = max_t(int, vmin, adjusted_mode->crtc_vtotal);
+		vmax = max_t(int, vmax, adjusted_mode->crtc_vtotal);
+
+		if (vmin >= vmax)
+			return;
+
+		/*
+		 * flipline determines the min vblank length the hardware will
+		 * generate, and flipline>=vmin+1, hence we reduce vmin by one
+		 * to make sure we can get the actual min vblank length.
+		 */
+		crtc_state->vrr.vmin = vmin - 1;
+		crtc_state->vrr.vmax = vmax;
+
+		crtc_state->vrr.flipline = crtc_state->vrr.vmin + 1;
+		crtc_state->vrr.fixed_rr = false;
+	}
 
 	/*
 	 * When panel is VRR capable and userspace has
 	 * not enabled adaptive sync mode then Fixed Average
 	 * Vtotal mode should be enabled.
 	 */
-	if (crtc_state->uapi.vrr_enabled) {
+	if (crtc_state->uapi.vrr_enabled || crtc_state->vrr.fixed_rr) {
 		crtc_state->vrr.enable = true;
 		crtc_state->mode_flags |= I915_MODE_FLAG_VRR;
 	} else if (is_cmrr_frac_required(crtc_state) && is_edp) {
@@ -426,6 +441,10 @@ void intel_vrr_get_config(struct intel_crtc_state *crtc_state)
 						     TRANS_VRR_VMAX(dev_priv, cpu_transcoder)) + 1;
 		crtc_state->vrr.vmin = intel_de_read(dev_priv,
 						     TRANS_VRR_VMIN(dev_priv, cpu_transcoder)) + 1;
+
+		if (crtc_state->vrr.vmax == crtc_state->vrr.flipline &&
+		    crtc_state->vrr.vmin == crtc_state->vrr.flipline)
+			crtc_state->vrr.fixed_rr = true;
 	}
 
 	if (crtc_state->vrr.enable) {
-- 
2.45.2