Add information about cgsix boards and notes on how to set the graphics

resolution.

This page should probably be shared with sun3 and sparc64 at some point.

share/man/man4/man4.sparc/cgsix.4

@@ -1,4 +1,4 @@
-.\"	$NetBSD: cgsix.4,v 1.7 1999/12/17 16:23:24 abs Exp $
+.\"	$NetBSD: cgsix.4,v 1.8 2002/09/11 15:34:08 jdc Exp $
 .\"
 .\" Copyright 1994
 .\"	The Regents of the University of California.  All rights reserved.
@@ -49,18 +49,126 @@
 .Cd "cgsix0 at obio0 addr 0x0b000000 level 4" Pq sun4/100
 .Sh DESCRIPTION
 The
-.Nm cgsix
+.Nm
 is a memory based color frame buffer.
 It supports the minimal ioctl's needed to run
 .Xr X 1 .
+.Pp
+There are several versions of the
+.Nm
+board.  The Sun part numbers and
+board types are:
+.Pp
+.Bl -tag -width "501-1717, 501-2018, 501-2039" -compact
+.It "501-1374, 501-1532"
+P4 GX
+.It 501-1505
+P4 GX with 3/80 backpanel
+.It "501-1481, 501-1645"
+Sbus double-width GX
+.It "501-1672, 501-1996"
+Sbus GX
+.It "501-1717, 501-2018, 501-2039"
+Sbus GX+
+.It "501-2325, 501-2922"
+Sbus TGX
+.It "501-2253, 501-2955"
+Sbus TGX+
+.El
+.Pp
+There are also on-board
+.Sq GX
+cards in the
+.Sq Sparcstation IPX
+and
+.Sq Sparcstation LX
+machines.
+.Pp
+The
+.Sq GX
+and
+.Sq TGX
+cards have 1Mb of on-board memory and support a maximum graphics resolution
+of 1152x900.  The
+.Sq GX\&+
+cards have 4Mb of on-board memory and support a maximum resolution of
+1280x1024.  The
+.Sq TGX\&+
+cards have 4Mb
+of on-board memory and support a maximum resolution of 1600x1280.  The
+.Sq TGX
+(Turbo GX) cards are faster than the
+.Sq GX
+cards.
+.Pp
+The number of supported resolutions varies by card type.  All cards support a
+resolution of 1152x900 at 66Hz.  All but the P4 and double-width cards support
+a resolution of 1152x900 at 76Hz.  The cards default to a resolution dependent
+on the attached monitor (usually 1152x900).
+.Pp
+It is only possible to change the resolution of a
+.Nm
+card from the PROM before the operating system is loaded.  For the primary
+card, this can be done using the
+.Sq output-device
+PROM field.  For example, for a
+.Sq TGX+
+card, the following PROM command will set the resolution to 1280x1024 at
+76Hz:
+.Bd -literal -offset indent
+setenv output-device screen:r1280x1024x76
+.Ed
+.Pp
+For secondary cards, a different method must be used to set the resolution.
+For a machine with OpenBoot 2.x or 3.x, and assuming a
+.Sq TGX
+card at Sbus slot 1, the following PROM commands will set the resolution to
+1024x768 at 60Hz:
+.Bd -literal -offset indent
+nvedit
+probe-all
+" /iommu/sbus/cgsix@1" select-dev
+r1024x768x60
+" /iommu/sbus/cgsix@1" " set-resolution" execute-device-method
+device-end
+install-console
+banner
+^C
+nvstore
+setenv use-nvramrc? true
+reset
+.Ed
+.Pp
+For Sun4c machines, the device-path above would be:
+.Bd -literal -offset indent
+" /sbus/cgsix@1"
+.Ed
+.Pp
+For Sun-4 and Sun-3 systems, it is only possible to change PROM fields by
+altering byte values.  For these systems, it is probably easier to use the
+.Xr eeprom 8
+command to set the
+.Va scrsize
+field to the desired resolution.
+.Sh EXAMPLES
+.Cd "cgsix0 at obio0 addr 0xfb000000 level 4: cgsix/p4, 1152 x 900, rev 1"
+.Cd "cgsix0 at sbus0 slot 0 offset 0x0 level 9: SUNW,501-2325, 1152 x 900, rev 11"
+.Cd "cgsix0 at sbus0 slot 0 offset 0x0 level 9: SUNW,501-2253, 1280 x 1024, rev 11"
 .Sh SEE ALSO
 .Xr bwtwo 4 ,
 .Xr cgtwo 4 ,
 .Xr cgthree 4 ,
 .Xr cgfour 4 ,
 .Xr cgeight 4 ,
-.Xr tcx 4
+.Xr tcx 4 ,
+.Xr eeprom 8
 .Sh BUGS
+The double-width
+.Sq GX
+and the
+.Sq GX\&+
+cards are not compatible with UltraSparc machines.
+.Pp
 Several firmware revisions on
 .Nm
 boards have a terminal emulation bug that shows up when using the