drm: add test for AGP devices and driver override for it.

Added device_is_agp callback to drm_driver.  This function is called by the
platform-specific drm_device_is_agp function.  Added implementation of this
function the the Linux-specific portion of the MGA driver to detect PCI G450
cards.  Added code to the Linux-specific portion of the generic DRM layer to
not initialize AGP infrastructure if the card is not AGP (this matches what
already existed in BSD).

Fix up i810/i830 and i915 drivers to always return AGP as they don't always
report the capability.

Fix the MGA to not report AGP for a card that has an AGP chip behind a PCI
bridge.

From: Ian Romanick, Dave Airlie, Alan Hourihane
Signed-off-by: Dave Airlie <airlied@linux.ie>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/char/drm/i915_drv.h b/drivers/char/drm/i915_drv.h
index 93080868d18f..70ed4e68eac8 100644
--- a/drivers/char/drm/i915_drv.h
+++ b/drivers/char/drm/i915_drv.h
@@ -103,6 +103,7 @@ typedef struct drm_i915_private {
 extern void i915_kernel_lost_context(drm_device_t * dev);
 extern void i915_driver_pretakedown(drm_device_t *dev);
 extern void i915_driver_prerelease(drm_device_t *dev, DRMFILE filp);
+extern int i915_driver_device_is_agp(drm_device_t *dev);
 
 /* i915_irq.c */
 extern int i915_irq_emit(DRM_IOCTL_ARGS);