diff options
| author | Laszlo Agocs <laszlo.agocs@qt.io> | 2016-12-22 12:19:29 +0100 |
|---|---|---|
| committer | Laszlo Agocs <laszlo.agocs@qt.io> | 2017-01-12 14:44:15 +0000 |
| commit | 5925021385abd8a45b620bdba121d84e27132265 (patch) | |
| tree | f4415f9860e115c8e1b88b34fb355a0809d56621 | |
| parent | 84c76544f72fb2808ae91f9cd7579199535cac37 (diff) | |
embedded: Document the new DRM dumb buffer support for linuxfb
Change-Id: Ic00e5e623113cfd38b452ed046672efc8602a0e8
Reviewed-by: Topi Reiniö <topi.reinio@qt.io>
| -rw-r--r-- | doc/src/platforms/emb-linux.qdoc | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/doc/src/platforms/emb-linux.qdoc b/doc/src/platforms/emb-linux.qdoc index 3c9559c0f..319e8be6d 100644 --- a/doc/src/platforms/emb-linux.qdoc +++ b/doc/src/platforms/emb-linux.qdoc @@ -300,6 +300,19 @@ Linux. Only software-rendered content is supported. Note that on some setups the display performance is expected to be limited. + As of Qt 5.9, DRM dumb buffer support is also available due to fbdev being + deprecated in the Linux kernel. This must be requested by setting the + \c QT_QPA_FB_DRM environment variable to a non-zero value. When set, provided + that dumb buffers are supported by the system, legacy framebuffer devices like + \c{/dev/fb0} are never accessed. Instead, rendering is set up via the DRM + APIs, similarly to the \c{eglfs_kms} backend of eglfs. The output will be + double-buffered and page flipped, providing proper vsync for software-rendered + content as well. + + \note when dumb buffers are in use, none of the options described below are + applicable since properties like physical and logical screen sizes are all + queried automatically. + The \c linuxfb plugin allows specifying additional settings by passing them in the \c QT_QPA_PLATFORM environment variable or \c -platform command-line option. For example, \c {QT_QPA_PLATFORM=linuxfb:fb=/dev/fb1} specifies that |