Add support for different drm debug levels

Binary package hint: xdiagnose

http://kernel.ubuntu.com/git?p=ubuntu/ubuntu-natty.git;a=blob;f=include/drm/drmP.h;h=348843b80150b1aa4a365ac95b469c1acb7a6453;hb=HEAD

#define DRM_UT_CORE 0x01
  91 #define DRM_UT_DRIVER 0x02
  92 #define DRM_UT_KMS 0x04
  93 /*
  94 * Three debug levels are defined.
  95 * drm_core, drm_driver, drm_kms
  96 * drm_core level can be used in the generic drm code. For example:
  97 * drm_ioctl, drm_mm, drm_memory
  98 * The macro definiton of DRM_DEBUG is used.
  99 * DRM_DEBUG(fmt, args...)
 100 * The debug info by using the DRM_DEBUG can be obtained by adding
 101 * the boot option of "drm.debug=1".
 102 *
 103 * drm_driver level can be used in the specific drm driver. It is used
 104 * to add the debug info related with the drm driver. For example:
 105 * i915_drv, i915_dma, i915_gem, radeon_drv,
 106 * The macro definition of DRM_DEBUG_DRIVER can be used.
 107 * DRM_DEBUG_DRIVER(fmt, args...)
 108 * The debug info by using the DRM_DEBUG_DRIVER can be obtained by
 109 * adding the boot option of "drm.debug=0x02"
 110 *
 111 * drm_kms level can be used in the KMS code related with specific drm driver.
 112 * It is used to add the debug info related with KMS mode. For example:
 113 * the connector/crtc ,
 114 * The macro definition of DRM_DEBUG_KMS can be used.
 115 * DRM_DEBUG_KMS(fmt, args...)
 116 * The debug info by using the DRM_DEBUG_KMS can be obtained by
 117 * adding the boot option of "drm.debug=0x04"
 118 *
 119 * If we add the boot option of "drm.debug=0x06", we can get the debug info by
 120 * using the DRM_DEBUG_KMS and DRM_DEBUG_DRIVER.
 121 * If we add the boot option of "drm.debug=0x05", we can get the debug info by
 122 * using the DRM_DEBUG_KMS and DRM_DEBUG.
 123 */