drm/nouveau: prefer XBGR2101010 for addfb ioctl

commit c20bb155c2c5acb775f68be5d84fe679687c3c1e upstream.

Nouveau only exposes support for XBGR2101010. Prior to the atomic
conversion, drm would pass in the wrong format in the framebuffer, but
it was always ignored -- both userspace (xf86-video-nouveau) and the
kernel driver agreed on the layout, so the fact that the format was
wrong didn't matter.

With the atomic conversion, nouveau all of a sudden started caring about
the exact format, and so the previously-working code in
xf86-video-nouveau no longer functioned since the (internally-assigned)
format from the addfb ioctl was wrong.

This change adds infrastructure to allow a drm driver to specify that it
prefers the XBGR format variant for the addfb ioctl, and makes nouveau's
nv50 display driver set it. (Prior gens had no support for 30bpp at all.)

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Cc: stable@vger.kernel.org # v4.10+
Acked-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20180203191123.31507-1-imirkin@alum.mit.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/drm_framebuffer.c b/drivers/gpu/drm/drm_framebuffer.c
index af279844d7ceb69d44ec9bf260ea63d9435b6de4..dd4727489b84d3d0f33f2119f32d266bb63575c4 100644 (file)
--- a/drivers/gpu/drm/drm_framebuffer.c
+++ b/drivers/gpu/drm/drm_framebuffer.c
@@ -118,6 +118,10 @@ int drm_mode_addfb(struct drm_device *dev,
        r.pixel_format = drm_mode_legacy_fb_format(or->bpp, or->depth);
        r.handles[0] = or->handle;
 
+       if (r.pixel_format == DRM_FORMAT_XRGB2101010 &&
+           dev->driver->driver_features & DRIVER_PREFER_XBGR_30BPP)
+               r.pixel_format = DRM_FORMAT_XBGR2101010;
+
        ret = drm_mode_addfb2(dev, &r, file_priv);
        if (ret)
                return ret;

diff --git a/drivers/gpu/drm/nouveau/nv50_display.c b/drivers/gpu/drm/nouveau/nv50_display.c
index fb47d46050ec4f688664065f94ade1d9ab3bb2c0..6e196bc01118c546dc72e56fabb139f8a48961f7 100644 (file)
--- a/drivers/gpu/drm/nouveau/nv50_display.c
+++ b/drivers/gpu/drm/nouveau/nv50_display.c
@@ -4426,6 +4426,7 @@ nv50_display_create(struct drm_device *dev)
        nouveau_display(dev)->fini = nv50_display_fini;
        disp->disp = &nouveau_display(dev)->disp;
        dev->mode_config.funcs = &nv50_disp_func;
+       dev->driver->driver_features |= DRIVER_PREFER_XBGR_30BPP;
        if (nouveau_atomic)
                dev->driver->driver_features |= DRIVER_ATOMIC;
 

diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h
index 71bbaaec836d29f491fc78c74c5fa4801873fa9b..305304965b898dfff9e8eb50b5b3c7c6ab0a5ff1 100644 (file)
--- a/include/drm/drm_drv.h
+++ b/include/drm/drm_drv.h
@@ -55,6 +55,7 @@ struct drm_mode_create_dumb;
 #define DRIVER_ATOMIC                  0x10000
 #define DRIVER_KMS_LEGACY_CONTEXT      0x20000
 #define DRIVER_SYNCOBJ                  0x40000
+#define DRIVER_PREFER_XBGR_30BPP        0x80000
 
 /**
  * struct drm_driver - DRM driver structure