diff options
Diffstat (limited to 'Documentation/fb')
| -rw-r--r-- | Documentation/fb/api.rst | 4 | ||||
| -rw-r--r-- | Documentation/fb/efifb.rst | 38 |
2 files changed, 37 insertions, 5 deletions
diff --git a/Documentation/fb/api.rst b/Documentation/fb/api.rst index 79ec33dded74..4f00e7196fef 100644 --- a/Documentation/fb/api.rst +++ b/Documentation/fb/api.rst @@ -290,12 +290,12 @@ the FB_CAP_FOURCC bit in the fb_fix_screeninfo capabilities field. FOURCC definitions are located in the linux/videodev2.h header. However, and despite starting with the V4L2_PIX_FMT_prefix, they are not restricted to V4L2 and don't require usage of the V4L2 subsystem. FOURCC documentation is -available in Documentation/media/uapi/v4l/pixfmt.rst. +available in Documentation/userspace-api/media/v4l/pixfmt.rst. To select a format, applications set the grayscale field to the desired FOURCC. For YUV formats, they should also select the appropriate colorspace by setting the colorspace field to one of the colorspaces listed in linux/videodev2.h and -documented in Documentation/media/uapi/v4l/colorspaces.rst. +documented in Documentation/userspace-api/media/v4l/colorspaces.rst. The red, green, blue and transp fields are not used with the FOURCC-based API. For forward compatibility reasons applications must zero those fields, and diff --git a/Documentation/fb/efifb.rst b/Documentation/fb/efifb.rst index 04840331a00e..6badff64756f 100644 --- a/Documentation/fb/efifb.rst +++ b/Documentation/fb/efifb.rst @@ -2,8 +2,10 @@ What is efifb? ============== -This is a generic EFI platform driver for Intel based Apple computers. -efifb is only for EFI booted Intel Macs. +This is a generic EFI platform driver for systems with UEFI firmware. The +system must be booted via the EFI stub for this to be usable. efifb supports +both firmware with Graphics Output Protocol (GOP) displays as well as older +systems with only Universal Graphics Adapter (UGA) displays. Supported Hardware ================== @@ -12,11 +14,14 @@ Supported Hardware - Macbook - Macbook Pro 15"/17" - MacMini +- ARM/ARM64/X86 systems with UEFI firmware How to use it? ============== -efifb does not have any kind of autodetection of your machine. +For UGA displays, efifb does not have any kind of autodetection of your +machine. + You have to add the following kernel parameters in your elilo.conf:: Macbook : @@ -28,6 +33,9 @@ You have to add the following kernel parameters in your elilo.conf:: Macbook Pro 17", iMac 20" : video=efifb:i20 +For GOP displays, efifb can autodetect the display's resolution and framebuffer +address, so these should work out of the box without any special parameters. + Accepted options: ======= =========================================================== @@ -36,4 +44,28 @@ nowc Don't map the framebuffer write combined. This can be used when large amounts of console data are written. ======= =========================================================== +Options for GOP displays: + +mode=n + The EFI stub will set the mode of the display to mode number n if + possible. + +<xres>x<yres>[-(rgb|bgr|<bpp>)] + The EFI stub will search for a display mode that matches the specified + horizontal and vertical resolution, and optionally bit depth, and set + the mode of the display to it if one is found. The bit depth can either + "rgb" or "bgr" to match specifically those pixel formats, or a number + for a mode with matching bits per pixel. + +auto + The EFI stub will choose the mode with the highest resolution (product + of horizontal and vertical resolution). If there are multiple modes + with the highest resolution, it will choose one with the highest color + depth. + +list + The EFI stub will list out all the display modes that are available. A + specific mode can then be chosen using one of the above options for the + next boot. + Edgar Hucek <gimli@dark-green.com> |