On Sun, Jan 13, 2002 at 09:13:23PM -0800, Matthew Dharm wrote:
> As I understand it, 64-bit support is really two different things: 64-bit
> data path (i.e. unsigned long long) and 64-bit addressing (for more than 4G
> of RAM).
Right but due to the CPU architecture of pre-MIPS64 CPUs they always come
together unless the software does funny attempts at truncating OS support
to just 32-bit. So the 32-bit kernel gives you none of the two, the mips64
kernel both.
> My understanding is that "MIPS64" generally refers to a kernel which
> supports a 64-bit data path, but we're still limited to 32-bit addressing.
> Is that correct?
MIPS64 is MIPS's MIPS64 processor architecture, mips64 is the 64-bit kernel.
That may sound like nitpicking but it's important to understand that both
are not the same.
> I suspect that this is very much a toolchain issue, as I don't think gcc
> will generate 64-bit addressing code.
Gcc is fine; the problem are binutils, that is as and ld. As a result of
the gcc problems we don't have a 64-bit userspace either so all software
running on 64-bit kernels is currently old 32-bit software running in
compatibility mode.
Ralf
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