openpower/linux/linux-0003-drm-ast-Default-to-8bpp-on-big-endian.patch

From 3974f00104e399e91a0ab0f4b0f5e26e1f5e2ff9 Mon Sep 17 00:00:00 2001
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Fri, 31 Oct 2014 15:06:38 +1100
Subject: [PATCH 03/17] drm/ast: Default to 8bpp on big endian

This chip is LE only (some versions support HW swappers but not
the latest and the driver doesn't anyway).

I tried using the "foreign endian" fb flag but it appears to be
busted, so instead, default to endian-neutral 8bpp for BE.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Joel Stanley <joel@jms.id.au>
---
 drivers/gpu/drm/ast/ast_fb.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/gpu/drm/ast/ast_fb.c b/drivers/gpu/drm/ast/ast_fb.c
index ff68eef..c532c69 100644
--- a/drivers/gpu/drm/ast/ast_fb.c
+++ b/drivers/gpu/drm/ast/ast_fb.c
@@ -345,7 +345,20 @@ int ast_fbdev_init(struct drm_device *dev)
 	/* disable all the possible outputs/crtcs before entering KMS mode */
 	drm_helper_disable_unused_functions(dev);
 
+	/*
+	 * This chip is LE only (some versions support HW swappers but not
+	 * the latest and the driver doesn't anyway).
+	 *
+	 * I tried using the "foreign endian" fb flag but it appears to be
+	 * busted, so instead, default to endian-neutral 8bpp for BE.
+	 *
+	 * (and it's faster !)
+	 */
+#if defined(__BIG_ENDIAN)
+	ret = drm_fb_helper_initial_config(&afbdev->helper, 8);
+#else
 	ret = drm_fb_helper_initial_config(&afbdev->helper, 32);
+#endif
 	if (ret)
 		goto fini;
 
-- 
2.5.0