svn commit: r216782 - head/sys/i386/conf

[Bruce Evans]

On Tue, 28 Dec 2010, Warner Losh wrote:

> Log:
>  Revert r216777, per jhb@

I didn't see "per jhb@".  I think the bug DEFAULTS being included
unconditionally (and maybe the name of DEFAULTS -- defaults hould be
optional).

> Modified: head/sys/i386/conf/NOTES
> ==============================================================================
> --- head/sys/i386/conf/NOTES	Tue Dec 28 22:44:32 2010	(r216781)
> +++ head/sys/i386/conf/NOTES	Tue Dec 28 22:45:29 2010	(r216782)
> @@ -284,8 +284,7 @@ device		apm_saver	# Requires APM
> #
> # ISA bus
> #
> -# Already in DEFAULTS, which means we don't need it here.
> -#device		isa		# Required by npx(4)
> +device		isa		# Required by npx(4)

This comment seems wrong.  isa used to be required for the isa resources
related to irq13, but npx no longer supports irq13.  It now seems to use
isa only for PNPBIOS, but that is ifdefed so it doesn't require isa
(except for test coverage).

>
> #
> # Options for `isa':
> @@ -373,8 +372,7 @@ options		X86BIOS
>
> #
> # The Numeric Processing eXtension driver.  This is non-optional.
> -# Already in DEFAULTS, which means we don't need it here.
> -#device		npx
> +device		npx
> hint.npx.0.flags="0x0"
> hint.npx.0.irq="13"
>

These hints are more clearly garbage:
- the flags hint hasn't worked since FreeBSD-4 or earlier, where it
    controlled use of npx for bcopy and bzero (but this use stopped being
    useful with Pentium 1's many years before FreeBSD-4 was released).
    The flags hint remained referenced until rev.1.182 (2010/06/23), but
    only in ifdefed-out code.  Then the dead code was removed too.
- the support for irq13 was removed in rev.1.183 (also on 2010/06/23).

npx.c still has some references to removed code in comments (several IRQ13's
and one "BUSY# latch".  The BUSY# latch was only ISA address used IIRC.

npx used to use nexus for configuring the flags and irq at least.  I think
it no longer does, but nexus.c still gives npx as an example of special
handling in a comment.

npx.4 still has hints for the unused(?) nexus, the unused port for the BUSY#
latch, the unused flags for bcopying (including a very detailed description
of when these flags are applied, which rotted started with ifdefing out the
code that applied them), and the unused irq.  After removing these
anachronisms including the BUGS section (which is entirely FUD about the
unused irq13), npx.4 has about 5 useful lines.

Bruce