Re: [RFT] Port 0x80 I/O speed

[Rene Herman]

On 12-12-07 13:59, linux-os (Dick Johnson) wrote:

> On Tue, 11 Dec 2007, [utf-8] Alejandro Riveira Fern?ndez wrote:

> > On my AMD 3800 X2 (2000MHz) ULi M1697 2.6.24-rc5 i get:
> >
> > cycles: out 1844674407370808, in 1844674407369087
> >
> > It is not constant but variations are not significant afaics
>
> It looks as though this hardware does not have a port 0x80
> and its access is trapped by the hardware with a long time-out!
> This may be the reason when the _p was called "harmful" on this
> platform!
>
> I'm not sure the "rules" for port access allow for this kind of
> behavior. This design may be defective, needing to be brought
> to the attention of the vendor. A decent vendor would update
> a FPGA and provide code to burn a new BIOS.

I'm afraid it's just the test that is "defective" as 64-bit code. For some 
reason "=A" doesn't mean edx:eax on amd64 even though it's a useful register 
pair to be able to name there as well. Didn't catch that being without amd64 
machines myself.

Oh well. gcc -m32 fixes it...

Rene.
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