Commit ad77c537 authored by Ville Syrjälä's avatar Ville Syrjälä
Browse files

drm/i915: Check timings against hardware maximums 



Validate that all display timings fit within the number of bits
we have in the transcoder timing registers.

The limits are:
hsw+:
 4k: vdisplay, vblank_start
 8k: everything else
gen3+:
 4k: h/vdisplay, h/vblank_start
 8k: everything else
gen2:
 2k: h/vdisplay, h/vblank_start
 4k: everything else

Also document the fact that the mode_config.max_width/height limits
refer to just the max framebuffer dimensions we support. Which may
be larger than the max hdisplay/vdisplay.

Signed-off-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180615174406.12258-2-ville.syrjala@linux.intel.com


Reviewed-by: default avatarPaulo Zanoni <paulo.r.zanoni@intel.com>
parent 98fac1d5

drivers/gpu/drm/i915/intel_display.c

+35 −0
Original line number Diff line number Diff line
@@ -14570,6 +14570,10 @@ static enum drm_mode_status 
intel_mode_valid(struct drm_device *dev,

		 const struct drm_display_mode *mode)

{

	struct drm_i915_private *dev_priv = to_i915(dev);

	int hdisplay_max, htotal_max;

	int vdisplay_max, vtotal_max;



	/*

	 * Can't reject DBLSCAN here because Xorg ddxen can add piles

	 * of DBLSCAN modes to the output's mode list when they detect
@@ -14599,6 +14603,36 @@ intel_mode_valid(struct drm_device *dev, 
			   DRM_MODE_FLAG_CLKDIV2))

		return MODE_BAD;



	if (INTEL_GEN(dev_priv) >= 9 ||

	    IS_BROADWELL(dev_priv) || IS_HASWELL(dev_priv)) {

		hdisplay_max = 8192; /* FDI max 4096 handled elsewhere */

		vdisplay_max = 4096;

		htotal_max = 8192;

		vtotal_max = 8192;

	} else if (INTEL_GEN(dev_priv) >= 3) {

		hdisplay_max = 4096;

		vdisplay_max = 4096;

		htotal_max = 8192;

		vtotal_max = 8192;

	} else {

		hdisplay_max = 2048;

		vdisplay_max = 2048;

		htotal_max = 4096;

		vtotal_max = 4096;

	}



	if (mode->hdisplay > hdisplay_max ||

	    mode->hsync_start > htotal_max ||

	    mode->hsync_end > htotal_max ||

	    mode->htotal > htotal_max)

		return MODE_H_ILLEGAL;



	if (mode->vdisplay > vdisplay_max ||

	    mode->vsync_start > vtotal_max ||

	    mode->vsync_end > vtotal_max ||

	    mode->vtotal > vtotal_max)

		return MODE_V_ILLEGAL;



	return MODE_OK;

}
@@ -15037,6 +15071,7 @@ int intel_modeset_init(struct drm_device *dev) 
		}

	}



	/* maximum framebuffer dimensions */

	if (IS_GEN2(dev_priv)) {

		dev->mode_config.max_width = 2048;

		dev->mode_config.max_height = 2048;

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