diff mbox series

[3/3] drm/i915/dsi: Assert that vfp+vsync+vbp == vtotal on BXT/GLK

Message ID 20250314150136.22564-3-ville.syrjala@linux.intel.com (mailing list archive)
State New
Headers show
Series [1/3] drm/i915/dsi: Fix off by one in BXT_MIPI_TRANS_VTOTAL | expand

Commit Message

Ville Syrjala March 14, 2025, 3:01 p.m. UTC 
From: Ville Syrjälä <ville.syrjala@linux.intel.com>

Windows code seems to do some dodgy looking +/-1 adjustments
to some of the vertical timings. Not sure if that's correct
or not, but let's at least cross check some of the values
we got from the hardware to double check whether the GOP
did the same or not.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
---
 drivers/gpu/drm/i915/display/vlv_dsi.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/display/vlv_dsi.c b/drivers/gpu/drm/i915/display/vlv_dsi.c
index 661de51dfd22..cdab04727c7d 100644
--- a/drivers/gpu/drm/i915/display/vlv_dsi.c
+++ b/drivers/gpu/drm/i915/display/vlv_dsi.c
@@ -1024,7 +1024,7 @@  static void bxt_dsi_get_pipe_config(struct intel_encoder *encoder,
 	unsigned int lane_count = intel_dsi->lane_count;
 	unsigned int bpp, fmt;
 	enum port port;
-	u16 hactive, hfp, hsync, hbp, vfp, vsync;
+	u16 hactive, hfp, hsync, hbp, vfp, vsync, vbp;
 	u16 hfp_sw, hsync_sw, hbp_sw;
 	u16 crtc_htotal_sw, crtc_hsync_start_sw, crtc_hsync_end_sw,
 				crtc_hblank_start_sw, crtc_hblank_end_sw;
@@ -1088,6 +1088,7 @@  static void bxt_dsi_get_pipe_config(struct intel_encoder *encoder,
 
 	/* vertical values are in terms of lines */
 	vfp = intel_de_read(display, MIPI_VFP_COUNT(display, port));
+	vbp = intel_de_read(display, MIPI_VBP_COUNT(display, port));
 	vsync = intel_de_read(display, MIPI_VSYNC_PADDING_COUNT(display, port));
 
 	adjusted_mode->crtc_htotal = hactive + hfp + hsync + hbp;
@@ -1096,6 +1097,8 @@  static void bxt_dsi_get_pipe_config(struct intel_encoder *encoder,
 	adjusted_mode->crtc_hblank_start = adjusted_mode->crtc_hdisplay;
 	adjusted_mode->crtc_hblank_end = adjusted_mode->crtc_htotal;
 
+	drm_WARN_ON(display->drm, adjusted_mode->crtc_vdisplay +
+		    vfp + vsync + vbp != adjusted_mode->crtc_vtotal);
 	adjusted_mode->crtc_vsync_start = vfp + adjusted_mode->crtc_vdisplay;
 	adjusted_mode->crtc_vsync_end = vsync + adjusted_mode->crtc_vsync_start;
 	adjusted_mode->crtc_vblank_start = adjusted_mode->crtc_vdisplay;