drm: fixes for powerpc

Remove a bogus check on whether an area is memory (we need a better interface)
also change pgprot flags for powerpc
don't check on x86-64 either

From: Paul Mackerras <paulus@samba.org>
Signed-off-by: Dave Airlie <airlied@linux.ie>

drivers/char/drm/drm_bufs.c

@@ -152,7 +152,7 @@ int drm_addmap(drm_device_t * dev, unsigned int offset,
 	switch ( map->type ) {
 	case _DRM_REGISTERS:
 	case _DRM_FRAME_BUFFER:
-#if !defined(__sparc__) && !defined(__alpha__) && !defined(__ia64__)
+#if !defined(__sparc__) && !defined(__alpha__) && !defined(__ia64__) && !defined(__powerpc64__) && !defined(__x86_64__)
 		if ( map->offset + map->size < map->offset ||
 		     map->offset < virt_to_phys(high_memory) ) {
 			drm_free( map, sizeof(*map), DRM_MEM_MAPS );
@@ -309,7 +309,7 @@ int drm_addmap_ioctl(struct inode *inode, struct file *filp,
 	if (put_user(handle, &argp->handle))
 		return -EFAULT;
 	return 0;
-	}
+}
 
 
 /**

drivers/char/drm/drm_vm.c

@@ -578,17 +578,17 @@ int drm_mmap(struct file *filp, struct vm_area_struct *vma)
                 /* fall through to _DRM_FRAME_BUFFER... */        
 	case _DRM_FRAME_BUFFER:
 	case _DRM_REGISTERS:
-		if (map->offset >= __pa(high_memory)) {
 #if defined(__i386__) || defined(__x86_64__)
-			if (boot_cpu_data.x86 > 3 && map->type != _DRM_AGP) {
-				pgprot_val(vma->vm_page_prot) |= _PAGE_PCD;
-				pgprot_val(vma->vm_page_prot) &= ~_PAGE_PWT;
-			}
+		if (boot_cpu_data.x86 > 3 && map->type != _DRM_AGP) {
+			pgprot_val(vma->vm_page_prot) |= _PAGE_PCD;
+			pgprot_val(vma->vm_page_prot) &= ~_PAGE_PWT;
+		}
 #elif defined(__powerpc__)
-			pgprot_val(vma->vm_page_prot) |= _PAGE_NO_CACHE | _PAGE_GUARDED;
+		pgprot_val(vma->vm_page_prot) |= _PAGE_NO_CACHE;
+		if (map->type == _DRM_REGISTERS)
+			pgprot_val(vma->vm_page_prot) |= _PAGE_GUARDED;
 #endif
-			vma->vm_flags |= VM_IO;	/* not in core dump */
-		}
+		vma->vm_flags |= VM_IO;	/* not in core dump */
 #if defined(__ia64__)
 		if (efi_range_is_wc(vma->vm_start, vma->vm_end -
 				    vma->vm_start))