Re: [gentoo-mips] Reducing the number of the MIPS supported stages

[Joshua Kinard <kumba@gentoo.org>]

On 05/05/2014 19:36, Matt Turner wrote:
> On Mon, May 5, 2014 at 3:02 PM, Joshua Kinard <kumba@gentoo.org> wrote:
>> I cannot speak for anything outside of the standard/original MIPS ISAs, but
>> I thought we killed off mips1 long ago.  When did that come back?  Almost
>> anything out there should be able to handle mips2 at a bare minimum (only
>> R2000 and R3000-based systems, like certain DECStations, would need mips1).
>>  mips2 is also the branch point for the mips32r* ISAs, so if any of the
>> original, 32-bit ISAs should be kept, that would be mips2.  mips1 can go.
> 
> We've had this discussion before. If you're going to have >mips2
> stages, then there's zero reason to have mips2 stages since mips2
> effectively doesn't exist.

It's been a while, but I thought we only kept a mips2 stage1 around for
those that wanted a baseline to build their own stage2 or stage3's from.
You can do this with a mips1 as well, but mips2 is, more or less, the
baseline from which all other possible ISAs and stages can be built from, as
long as you don't care about R2k or R3k CPUs.  stage3's can be the higher
mips32r* ISAs.

I personally don't see a point in having mips1 or mips2 stage3's, only a
stage1 to use as a bootstrap for new machines or ISAs.

-- 
Joshua Kinard
Gentoo/MIPS
kumba@gentoo.org
4096R/D25D95E3 2011-03-28

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