gpx(4) color framebuffer driver for VS3100/m30

[Izumi Tsutsui <tsutsui%ceres.dti.ne.jp@localhost>]

Hi,

I've managed to port gpx(4) color framebuffer driver from OpenBSD/vax
 https://man.openbsd.org/OpenBSD-5.8/vax/gpx.4
and it just works at least on my VAXstation 3100/m30.
(just ~4 hours work)

 https://github.com/tsutsui/netbsd-src/compare/b9f95d729ffa10c13ca0421eecc75362871a802f..8d758bcc3e24997e05b919fe60cd7c55b8444599

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NetBSD 10.99.2 (VS3100) #13: Tue Jan 24 02:39:34 JST 2023
	tsutsui@mirage:/s/tsutsui/netbsd-src/sys/arch/vax/compile/VS3100
VAXstation 3100/m{30,40}
total memory = 8072 KB
avail memory = 4628 KB
timecounter: Timecounters tick every 10.000 msec
mainbus0 (root)
cpu0 at mainbus0: KA420, CVAX, 1KB L1 cache, 64KB L2 cache
vsbus0 at mainbus0
vsbus0: interrupt mask 0
le0 at vsbus0 csr 0x200e0000 vec 120 ipl 17 maskbit 5 buf 0x351000-0x360fff
le0: address 08:00:2b:11:dc:17
le0: 32 receive buffers, 8 transmit buffers
dz0 at vsbus0 csr 0x200a0000 vec 304 ipl 17 maskbit 6
dz0: 4 lines
lkkbd0 at dz0
wskbd0 at lkkbd0: console keyboard
lkms0 at dz0
wsmouse0 at lkms0 mux 0
lk201_decode: error b6
hdc0 at vsbus0 csr 0x200c0000 vec 774 ipl 17 maskbit 0
si0 at vsbus0 csr 0x200c0080 vec 770 ipl 17 maskbit 1
si0: NCR5380, SCSI ID 6
scsibus0 at si0: 8 targets, 8 luns per target
gpx0 at vsbus0 csr 0x3c000000 vec 104 ipl 15 maskbit 3
gpx0: : 1024x864 8 plane color framebuffer
wsdisplay0 at gpx0 kbdmux 1: console (std, vt100 emulation), using wskbd0
wsmux1: connecting to wsdisplay0
timecounter: Timecounter "mfpr" frequency 1000000 Hz quality 100
timecounter: Timecounter "clockinterrupt" frequency 100 Hz quality 0
scsibus0: waiting 2 seconds for devices to settle...
WARNING: system needs entropy for security; see entropy(7)
sd0 at scsibus0 target 3 lun 0: <DEC, RZ22     (C) DEC, 0618> disk fixed
sd0: 51216 KB, 776 cyl, 4 head, 33 sec, 512 bytes/sect x 102432 sectors
sd0: async, 8-bit transfers
boot device: le0
root on le0
nfs_boot: trying DHCP/BOOTP
nfs_boot: DHCP next-server: 192.168.20.1
nfs_boot: my_domain=ceres.dti.ne.jp
nfs_boot: my_addr=192.168.20.76
nfs_boot: my_mask=255.255.255.0
nfs_boot: gateway=192.168.20.1
nfs server mirage:/r/export/NetBSD/vax/root: not responding
nfs server mirage:/r/export/NetBSD/vax/root: is alive again
root on mirage:/r/export/NetBSD/vax/root
root file system type: nfs
kern.module.path=/stand/vax/10.99.2/modules
---

As OpenBSD/vax did, smg(4) driver for the on-board monochrome
framebuffer is disabled if optional gpx(4) is installed:
 https://man.openbsd.org/OpenBSD-5.8/vax/smg.4

I'm not sure current status of NetBSD/vax on VS3100, especially
framebuffers, but I'll commit the driver if there is no particular
objection.

Thanks,
---
Izumi Tsutsui