[PATCH] fix MGA DRM regression before 2.6.14

I've gotten a report on lkml, of a possible regression in the MGA DRM in
2.6.14-rc4 (since -rc1), I haven't been able to reproduce it here, but I've
figured out some possible issues in the mga code that were definitely
wrong, some of these are from DRM CVS, the main fix is the agp enable bit
on the old code path still used by everyone.....

Signed-off-by: Dave Airlie <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/char/drm/mga_dma.c

···
 				    drm_mga_dma_bootstrap_t * dma_bs)
 {
 	drm_mga_private_t * const dev_priv = (drm_mga_private_t *) dev->dev_private;
-	const unsigned int warp_size = mga_warp_microcode_size(dev_priv);
+	unsigned int warp_size = mga_warp_microcode_size(dev_priv);
 	int err;
 	unsigned  offset;
 	const unsigned secondary_size = dma_bs->secondary_bin_count
···
 		DRM_ERROR("Unable to bind AGP memory\n");
 		return err;
 	}
+
+	/* Make drm_addbufs happy by not trying to create a mapping for less
+	 * than a page.
+	 */
+	if (warp_size < PAGE_SIZE)
+		warp_size = PAGE_SIZE;
 
 	offset = 0;
 	err = drm_addmap( dev, offset, warp_size,
···
 				    drm_mga_dma_bootstrap_t * dma_bs)
 {
 	drm_mga_private_t * const dev_priv = (drm_mga_private_t *) dev->dev_private;
-	const unsigned int warp_size = mga_warp_microcode_size(dev_priv);
+	unsigned int warp_size = mga_warp_microcode_size(dev_priv);
 	unsigned int primary_size;
 	unsigned int bin_count;
 	int err;
···
 		DRM_ERROR("dev->dma is NULL\n");
 		return DRM_ERR(EFAULT);
 	}
+
+	/* Make drm_addbufs happy by not trying to create a mapping for less
+	 * than a page.
+	 */
+	if (warp_size < PAGE_SIZE)
+		warp_size = PAGE_SIZE;
 
 	/* The proper alignment is 0x100 for this mapping */
 	err = drm_addmap(dev, 0, warp_size, _DRM_CONSISTENT,
···
 	}
 
 	if (! dev_priv->used_new_dma_init) {
+
+		dev_priv->dma_access = MGA_PAGPXFER;
+		dev_priv->wagp_enable = MGA_WAGP_ENABLE;
+
 		dev_priv->status = drm_core_findmap(dev, init->status_offset);
 		if (!dev_priv->status) {
 			DRM_ERROR("failed to find status page!\n");
···
 		drm_mga_private_t *dev_priv = dev->dev_private;
 
 		if ((dev_priv->warp != NULL) 
-		    && (dev_priv->mmio->type != _DRM_CONSISTENT))
+		    && (dev_priv->warp->type != _DRM_CONSISTENT))
 			drm_core_ioremapfree(dev_priv->warp, dev);
 
 		if ((dev_priv->primary != NULL)