DRM: Armada: Add Armada DRM driver

This patch adds support for the pair of LCD controllers on the Marvell
Armada 510 SoCs.  This driver supports:
- multiple contiguous scanout buffers for video and graphics
- shm backed cacheable buffer objects for X pixmaps for Vivante GPU
  acceleration
- dual lcd0 and lcd1 crt operation
- video overlay on each LCD crt via DRM planes
- page flipping of the main scanout buffers
- DRM prime for buffer export/import

This driver is trivial to extend to other Armada SoCs.

Included in this commit is the core driver with no output support; output
support is platform and encoder driver dependent.

Tested-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

drivers/gpu/drm/armada/armada_fb.h

@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2012 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef ARMADA_FB_H
+#define ARMADA_FB_H
+
+struct armada_framebuffer {
+	struct drm_framebuffer	fb;
+	struct armada_gem_object *obj;
+	uint8_t			fmt;
+	uint8_t			mod;
+};
+#define drm_fb_to_armada_fb(dfb) \
+	container_of(dfb, struct armada_framebuffer, fb)
+#define drm_fb_obj(fb) drm_fb_to_armada_fb(fb)->obj
+
+struct armada_framebuffer *armada_framebuffer_create(struct drm_device *,
+	struct drm_mode_fb_cmd2 *, struct armada_gem_object *);
+
+#endif