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@@ -619,22 +619,33 @@ void intel_crt_init(struct drm_device *dev)
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<title>VBlank event handling</title>
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<para>
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The DRM core exposes two vertical blank related ioctls:
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- DRM_IOCTL_WAIT_VBLANK and DRM_IOCTL_MODESET_CTL.
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+ <variablelist>
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+ <varlistentry>
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+ <term>DRM_IOCTL_WAIT_VBLANK</term>
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+ <listitem>
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+ <para>
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+ This takes a struct drm_wait_vblank structure as its argument,
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+ and it is used to block or request a signal when a specified
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+ vblank event occurs.
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+ </para>
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+ </listitem>
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+ </varlistentry>
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+ <varlistentry>
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+ <term>DRM_IOCTL_MODESET_CTL</term>
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+ <listitem>
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+ <para>
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+ This should be called by application level drivers before and
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+ after mode setting, since on many devices the vertical blank
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+ counter is reset at that time. Internally, the DRM snapshots
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+ the last vblank count when the ioctl is called with the
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+ _DRM_PRE_MODESET command so that the counter won't go backwards
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+ (which is dealt with when _DRM_POST_MODESET is used).
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+ </para>
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+ </listitem>
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+ </varlistentry>
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+ </variablelist>
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<!--!Edrivers/char/drm/drm_irq.c-->
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</para>
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- <para>
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- DRM_IOCTL_WAIT_VBLANK takes a struct drm_wait_vblank structure
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- as its argument, and is used to block or request a signal when a
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- specified vblank event occurs.
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- </para>
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- <para>
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- DRM_IOCTL_MODESET_CTL should be called by application level
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- drivers before and after mode setting, since on many devices, the
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- vertical blank counter is reset at that time. Internally,
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- the DRM snapshots the last vblank count when the ioctl is called
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- with the _DRM_PRE_MODESET command so that the counter won't go
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- backwards (which is dealt with when _DRM_POST_MODESET is used).
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- </para>
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<para>
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To support the functions above, the DRM core provides several
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helper functions for tracking vertical blank counters, and
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