modedb default video mode support
Currently all frame buffer device drivers have their own video mode databases,
which is a mess and a waste of resources. The main idea of modedb is to have
- one routine to probe for video modes, which can be used by all frame buffer
devices
- one generic video mode database with a fair amount of standard videomodes
(taken from XFree86)
- the possibility to supply your own mode database for graphics hardware that
needs non-standard modes, like amifb and Mac frame buffer drivers (which
use macmodes.c)
When a frame buffer device receives a video= option it doesn't know, it should
consider that to be a video mode option. If no frame buffer device is specified
in a video= option, fbmem considers that to be a global video mode option.
Valid mode specifiers (mode_option argument):
<xres>x<yres>[-<bpp>][@<refresh>]
<name>[-<bpp>][@<refresh>]
with <xres>, <yres>, <bpp> and <refresh> decimal numbers and <name> a string.
Things between square brackets are optional.
To find a suitable video mode, you just call
int __init fb_find_mode(struct fb_var_screeninfo *var,
struct fb_info *info, const char *mode_option,
const struct fb_videomode *db, unsigned int dbsize,
const struct fb_videomode *default_mode,
unsigned int default_bpp)
with db/dbsize your non-standard video mode database, or NULL to use the
standard video mode database.
fb_find_mode() first tries the specified video mode (or any mode that matches,
e.g. there can be multiple 640x480 modes, each of them is tried). If that
fails, the default mode is tried. If that fails, it walks over all modes.
To specify a video mode at bootup, use the following boot options:
video=<driver>:<xres>x<yres>[-<bpp>][@refresh]
where <driver> is a name from the table below. Valid default modes can be
found in linux/drivers/video/modedb.c. Check your driver's documentation.
There may be more modes.
Drivers that support modedb boot options
Boot Name Cards Supported
ami - Amiga chipset frame buffer
aty128fb - ATI Rage128 / Pro frame buffer
atyfb - ATI Mach64 frame buffer
tdfx - 3D Fx frame buffer
BTW, only a few drivers use this at the moment. Others are to follow
(feel free to send patches).
Download Driver Pack
After your driver has been downloaded, follow these simple steps to install it.
Expand the archive file (if the download file is in zip or rar format).
If the expanded file has an .exe extension, double click it and follow the installation instructions.
Otherwise, open Device Manager by right-clicking the Start menu and selecting Device Manager.
Find the device and model you want to update in the device list.
Double-click on it to open the Properties dialog box.
From the Properties dialog box, select the Driver tab.
Click the Update Driver button, then follow the instructions.
Very important: You must reboot your system to ensure that any driver updates have taken effect.
For more help, visit our Driver Support section for step-by-step videos on how to install drivers for every file type.