.\"	$NetBSD: genfb.4,v 1.5 2019/07/26 10:52:03 wiz Exp $
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.\" Copyright (c) 2007 Michael Lorenz
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.Dd July 26, 2019
.Dt GENFB 4
.Os
.Sh NAME
.Nm genfb
.Nd generic framebuffer console driver
.Sh SYNOPSIS
.Cd "genfb* at pci?"
.Cd "genfb* at sbus?"
.Cd "genfb* at intvid?" Pq mac68k
.Cd "genfb* at macvid?" Pq mac68k
.Cd "wsdisplay* at genfb?"
.Sh DESCRIPTION
The
.Nm
driver provides support for generic framebuffers that have no native driver.
All it needs are some parameters to describe the framebuffer and an address.
.Ss PCI
When attaching to a
.Xr pci 4
bus the driver is configured via device properties:
.Bl -tag -width Dv
.It Dv width Pq Li uint32
Width in pixels.
.It Dv height Pq Li uint32
Height in pixels.
.It Dv stride Pq Li uint32
Line size in bytes.
.It Dv depth Pq Li uint32
Bits per pixel.
.It Dv is_console Pq Li bool
If true,
.Nm
will try to become the system console.
.It Dv address Pq Li uint32
Bus address of the framebuffer.
.El
.Ss SBus
When attaching to
.Xr sbus 4
all those parameters are retrieved from the firmware.
.Ss mac68k
All those parameters are configured with Mac OS,
and retrieved from the boot loader.
.Sh SEE ALSO
.Xr mac68k/intro 4 ,
.Xr pci 4 ,
.Xr sbus 4 ,
.Xr wscons 4 ,
.Xr wsdisplay 4
.Sh BUGS
There is no way to change the color map even when the firmware supports it.
The
.Xr pci 4
bus frontend has only been tested on macppc, i386, and amd64 and requires
machine dependent code to pass the properties mentioned above.
So far only macppc, i386, and amd64 provides them.