Subject: Re: make paddr_t 64bit on arc port
To: None <jeffs@geocast.com>
From: Noriyuki Soda <soda@sra.co.jp>
List: port-mips
Date: 06/08/2000 06:00:36
> > - the intention of this patch is to support 64bit device address
> >   space of arc port. framebuffer address and PCI bus space address of
> >   some platforms locate beyond 4GB (32bit address) boundary.
> 
> Really?  I'd generally consider the arc machines to be "small"
> machines.  I could see this for odd PCI devices, but I would have
> thought framebuffers would have a 32b compatable address space
> to maintain compatability with existing operating systems.

There are (at least) 2 platforms which have over 32bit device address:
	DeskStation Tyne:
		ISA memory space: 		0x100000000
		dedicated bounce memory:	0x100800000
		ISA I/O space:			0x900000000
	NEC RISCstation 2250:
		PCI memory space:		0x100000000

> When we designed bigger MIPS systems (Octane) at SGI, we kept
> compatability for a 32b OS even though we eventually did not
> use it.

Hmmm, so, forthcoming NetBSD/sgimips doesn't have to use _MIPS_PADDR_T_64BIT?
--
soda