[Intel-gfx] [PATCH 2/4] drm/i915: Reject modes where hdisplay or vdisplay is too small

[ville.syrjala at linux.intel.com]

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

Check the adjusted_mode hdisplay/vdisplay against the limits from BSpec.

Move the ctg+ zero front porch check to the same function, and change it
to use the crtc_ values as well.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/intel_display.c | 44 +++++++++++++++++++++++++++++++-----
 1 file changed, 38 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index a695888..fa02677 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -4197,11 +4197,46 @@ static void hsw_compute_ips_config(struct intel_crtc *crtc,
 				   pipe_config->pipe_bpp <= 24;
 }
 
+static int intel_check_mode(struct drm_crtc *crtc,
+			    const struct drm_display_mode *mode)
+{
+	struct drm_device *dev = crtc->dev;
+
+	/*
+	 * Cantiga+ cannot handle modes with a hsync front porch of 0.
+	 * WaPruneModeWithIncorrectHsyncOffset:ctg,elk,ilk,snb,ivb,vlv,hsw.
+	 */
+	if ((INTEL_INFO(dev)->gen > 4 || IS_G4X(dev)) &&
+	    mode->crtc_hsync_start == mode->crtc_hdisplay)
+		return -EINVAL;
+
+	if (IS_HASWELL(dev)) {
+		if (intel_pipe_has_type(crtc, INTEL_OUTPUT_HDMI) &&
+		    mode->crtc_hdisplay < 256)
+			return -EINVAL;
+
+		if (mode->crtc_hdisplay < 64 || mode->crtc_vdisplay < 7)
+			return -EINVAL;
+	} else if (INTEL_INFO(dev)->gen >= 5) {
+		if (mode->crtc_hdisplay < 64 || mode->crtc_vdisplay < 7)
+			return -EINVAL;
+	} else if (INTEL_INFO(dev)->gen >= 4) {
+		if (mode->crtc_hdisplay < 3 || mode->crtc_vdisplay < 3)
+			return -EINVAL;
+	} else {
+		if (mode->crtc_hdisplay < 2 || mode->crtc_vdisplay < 2)
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
 static int intel_crtc_compute_config(struct intel_crtc *crtc,
 				     struct intel_crtc_config *pipe_config)
 {
 	struct drm_device *dev = crtc->base.dev;
 	struct drm_display_mode *adjusted_mode = &pipe_config->adjusted_mode;
+	int ret;
 
 	/* FIXME should check pixel clock limits on all platforms */
 	if (INTEL_INFO(dev)->gen < 4) {
@@ -4236,12 +4271,9 @@ static int intel_crtc_compute_config(struct intel_crtc *crtc,
 	     intel_is_dual_link_lvds(dev)) || pipe_config->double_wide)
 		pipe_config->pipe_src_w &= ~1;
 
-	/* Cantiga+ cannot handle modes with a hsync front porch of 0.
-	 * WaPruneModeWithIncorrectHsyncOffset:ctg,elk,ilk,snb,ivb,vlv,hsw.
-	 */
-	if ((INTEL_INFO(dev)->gen > 4 || IS_G4X(dev)) &&
-		adjusted_mode->hsync_start == adjusted_mode->hdisplay)
-		return -EINVAL;
+	ret = intel_check_mode(&crtc->base, adjusted_mode);
+	if (ret)
+		return ret;
 
 	if ((IS_G4X(dev) || IS_VALLEYVIEW(dev)) && pipe_config->pipe_bpp > 10*3) {
 		pipe_config->pipe_bpp = 10*3; /* 12bpc is gen5+ */
-- 
1.8.1.5