Subject: Re: single-user shell on Dreamcast
To: Hiroyuki Bessho <bsh@grotto.iijnet.or.jp>
From: David Brownlee <abs@netbsd.org>
List: port-sh3
Date: 10/20/2000 09:42:11
On 20 Oct 2000, Hiroyuki Bessho wrote:

>   MACHINE is used to select a subset of source tree.  From this point
> of view, you can go without MACHINE=dreamcast, since dreamcast can
> share source code with evbsh3 (except for endian_machdep.h).
>
	Isn't this the same situation as on mips ports, which
	the handle with MACHINE_ARCH:

		MACHINE={dreamcast,mmeye,evbsh3el,evbsh3eb}
		MACHINE_ARCH={shel,sheb}

	As for splitting dreamcast out of evbsh3, there is prior art
	in both directions:

	- The arm32 port is in the process of splitting into riscpc, cats
	  and shark ports because the hardware in each is so different,
	  and a kernel which would run on all is unfeasible.

	- The sun3 port has kernels for sun3 and sun3x machines which
	  have significantly different hardware (different MMU, the sun3x
	  also shares a lot of hardware with the early sparcstations).

	Any solution should also consider how best to share code with
	mmeye. Maybe split the ports but move a lot of common code into
	arch/sh3 and dev/ic?

                David/absolute
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