pciconf(8): Decode ACS extended capability.

[np]

Summary

MFC after: 1 week
Sponsored by: Chelsio Communications

[np]

Here are a couple of examples from the motherboard that i tested it on, with the available caps disabled and enabled.

# pciconf -lc pcib4
pcib4@pci0:0:3:0:	class=0x060400 rev=0x02 hdr=0x01 vendor=0x8086 device=0x2f08 subvendor=0x8086 subdevice=0x0000
...
    ecap 000d[110] = ACS 1 Source Validation disabled, Translation Blocking disabled
                     P2P Req Redirect disabled, P2P Cmpl Redirect disabled
                     P2P Upstream Forwarding disabled, P2P Egress Control unavailable
                     P2P Direct Translated unavailable, Enhanced Capability unavailable


# pciconf -lc pcib4
pcib4@pci0:0:3:0:	class=0x060400 rev=0x02 hdr=0x01 vendor=0x8086 device=0x2f08 subvendor=0x8086 subdevice=0x0000
...
    ecap 000d[110] = ACS 1 Source Validation enabled, Translation Blocking enabled
                     P2P Req Redirect enabled, P2P Cmpl Redirect enabled
                     P2P Upstream Forwarding enabled, P2P Egress Control unavailable
                     P2P Direct Translated unavailable, Enhanced Capability unavailable

}

[kib]

usr.sbin/pciconf/cap.c

1033

static const char *const acc[] ?

1036

So should we check that the version is known?

[np]

Incorporate feedback from kib.