3 Jun
2013
3 Jun
'13
7:17 p.m.
On Mon, 3 Jun 2013, David Riley wrote:
On Jun 3, 2013, at 5:24 PM, Dave McGuire <mcguire
at neurotica.com> wrote:
It was just easier. The mainline Linux kernel even still has support for
FPU-less CPUs such as the i486SX and still has an FPU emulator available.
There are /tons/ of i486 processors still in use, too, both embedded and
network-connected.
On 06/03/2013 03:48 PM, Liam Proven wrote:
Ahh, then why was it so important for Linux to specifically de-support
only the 80386?
I know there's at least one byte-swapping instruction that appeared in
the 486. Beyond that, I assume it has more to do with the MMU and other
associated builtins (cache controller, maybe?) than with actual
instructions. When 486
and Pentium came out, they were treated as fast 386s, and
seemed to stay that way for a very long time.
Well, they are. The instruction set didn't change from the 80386 in
1985 until the Pentium-MMX in about 1996.