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.Dd November 6, 2026
.Dt LYNXFB 4
.Os
.Sh NAME
.Nm lynxfb
.Nd Silicon Motion SM712 framebuffer driver
.Sh SYNOPSIS
.Cd "lynxfb* at pci?"
.Cd "wsdisplay* at lynxfb?"
.Pp
.Cd options LYNXFB_DEFAULT_WIDTH=1024
.Cd options LYNXFB_DEFAULT_HEIGHT=600
.Cd options LYNXFB_DEFAULT_DEPTH=16
.Cd options LYNXFB_DEFAULT_STRIDE=0
.Sh DESCRIPTION
Silicon Motion's SM712 framebuffer chip (also known as the LynxEM+)
is a PCI display controller designed for mobile computers.
.Pp
The controller is capable of driving multiple displays simultaneously
and supports 2MB or 4MB of video RAM.
It also provides support for basic 2D acceleration, including a
blitter, and hardware support for YUV-RGB conversions.
The
.Nm
driver takes advantage of the 2D acceleration capabilities via the
.Xr rasops 9
framework.
.Pp
Only a limited range of resolutions are supported by the controller,
typically up to 1024x768, although it is often used with 1024x600
screens in small laptops, including the Lemote Yeeloong.
.Pp
It is also found in industrial and embedded computers, and servers
from various manufacturers.
Low-profile PCI cards utilizing the SM712 are also known to exist,
targeting the rackmount server market, such as the "Rattler M4".
.Sh SEE ALSO
.Xr wscons 4 ,
.Xr wsdisplay 4 ,
.Xr rasops 9
.Sh HISTORY
The
.Nm
driver originally appeared in
.Ox ,
where it was known as
.Sy smfb .
It was later ported to
.Nx
and first appeared in
.Nx 7.0 .