drm/bochs: fix DRM_FORMAT_* handling for big endian machines.

Use DRM_FORMAT_HOST_XRGB8888, so we are using the correct format code
on bigendian machines.  Also set the quirk_addfb_prefer_host_byte_order
mode_config bit so drm_mode_addfb() asks for the correct format code.

Create our own plane and use drm_crtc_init_with_planes() instead of
depending on the default created by drm_crtc_init().  That way the plane
format list is correct on bigendian machines.

Also re-add the framebuffer format check dropped by "df2052cc92 bochs:
convert to drm_fb_helper_fbdev_setup/teardown".

With this patch applied both ADDFB and ADDFB2 ioctls work correctly in
the bochs-drm.ko driver on big endian machines.  Without the patch only
ADDFB (which still seems to be used by the majority of userspace) works
correctly.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20180921134704.12826-4-kraxel@redhat.com

1 files changed, 33 insertions, 1 deletions

diff --git a/drivers/gpu/drm/bochs/bochs_kms.c b/drivers/gpu/drm/bochs/bochs_kms.c
index ea9a43d31bf1..f3fdaf945605 100644
--- a/drivers/gpu/drm/bochs/bochs_kms.c
+++ b/drivers/gpu/drm/bochs/bochs_kms.c
@@ -126,12 +126,43 @@ static const struct drm_crtc_helper_funcs bochs_helper_funcs = {
 	.commit = bochs_crtc_commit,
 };
 
+static const uint32_t bochs_formats[] = {
+	DRM_FORMAT_HOST_XRGB8888,
+};
+
+static struct drm_plane *bochs_primary_plane(struct drm_device *dev)
+{
+	struct drm_plane *primary;
+	int ret;
+
+	primary = kzalloc(sizeof(*primary), GFP_KERNEL);
+	if (primary == NULL) {
+		DRM_DEBUG_KMS("Failed to allocate primary plane\n");
+		return NULL;
+	}
+
+	ret = drm_universal_plane_init(dev, primary, 0,
+				       &drm_primary_helper_funcs,
+				       bochs_formats,
+				       ARRAY_SIZE(bochs_formats),
+				       NULL,
+				       DRM_PLANE_TYPE_PRIMARY, NULL);
+	if (ret) {
+		kfree(primary);
+		primary = NULL;
+	}
+
+	return primary;
+}
+
 static void bochs_crtc_init(struct drm_device *dev)
 {
 	struct bochs_device *bochs = dev->dev_private;
 	struct drm_crtc *crtc = &bochs->crtc;
+	struct drm_plane *primary = bochs_primary_plane(dev);
 
-	drm_crtc_init(dev, crtc, &bochs_crtc_funcs);
+	drm_crtc_init_with_planes(dev, crtc, primary, NULL,
+				  &bochs_crtc_funcs, NULL);
 	drm_crtc_helper_add(crtc, &bochs_helper_funcs);
 }
 
@@ -250,6 +281,7 @@ int bochs_kms_init(struct bochs_device *bochs)
 	bochs->dev->mode_config.fb_base = bochs->fb_base;
 	bochs->dev->mode_config.preferred_depth = 24;
 	bochs->dev->mode_config.prefer_shadow = 0;
+	bochs->dev->mode_config.quirk_addfb_prefer_host_byte_order = true;
 
 	bochs->dev->mode_config.funcs = &bochs_mode_funcs;