[PATCH] drm/i915/display: Avoid touching interlace mode registers

[Shekhar Chauhan]

Commit f71c9b7bc35f("drm/i915/display: Prune Interlace modes for Display >=12")
defeatures interlace modes starting with display version 12. However,
there are some paths in the driver that still touch interlace-related
registers/fields for display version >= 12. So, avoid touching those
registers/fields.

Signed-off-by: Shekhar Chauhan <shekhar.chauhan at intel.com>
---
 drivers/gpu/drm/i915/display/intel_display.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 3afb85fe8536..73b1fdf0b0ff 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -2686,7 +2686,7 @@ static void intel_set_transcoder_timings(const struct intel_crtc_state *crtc_sta
 		crtc_vblank_start = 1;
 	}
 
-	if (DISPLAY_VER(display) >= 4)
+	if (DISPLAY_VER(display) >= 4 && DISPLAY_VER(display) < 12)
 		intel_de_write(display,
 			       TRANS_VSYNCSHIFT(display, cpu_transcoder),
 			       vsyncshift);
@@ -2790,7 +2790,7 @@ static bool intel_pipe_is_interlaced(const struct intel_crtc_state *crtc_state)
 	struct intel_display *display = to_intel_display(crtc_state);
 	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
 
-	if (DISPLAY_VER(display) == 2)
+	if (DISPLAY_VER(display) == 2 || DISPLAY_VER(display) >= 12)
 		return false;
 
 	if (DISPLAY_VER(display) >= 9 ||
@@ -3164,10 +3164,12 @@ static void hsw_set_transconf(const struct intel_crtc_state *crtc_state)
 	if (display->platform.haswell && crtc_state->dither)
 		val |= TRANSCONF_DITHER_EN | TRANSCONF_DITHER_TYPE_SP;
 
-	if (crtc_state->hw.adjusted_mode.flags & DRM_MODE_FLAG_INTERLACE)
-		val |= TRANSCONF_INTERLACE_IF_ID_ILK;
-	else
-		val |= TRANSCONF_INTERLACE_PF_PD_ILK;
+	if (DISPLAY_VER(display) < 12) {
+		if (crtc_state->hw.adjusted_mode.flags & DRM_MODE_FLAG_INTERLACE)
+			val |= TRANSCONF_INTERLACE_IF_ID_ILK;
+		else
+			val |= TRANSCONF_INTERLACE_PF_PD_ILK;
+	}
 
 	if (display->platform.haswell &&
 	    crtc_state->output_format != INTEL_OUTPUT_FORMAT_RGB)
-- 
2.34.1