Re: RFC: outb 0x80 in inb_p, outb_p harmful on some modern AMD64 with MCP51 laptops

On 09-12-07 22:25, Pavel Machek wrote:

On Sun 2007-12-09 17:59:08, Andi Kleen wrote:

Yes, i guess switching to udelay at least on newer systems would
be a good idea. I'm not quite sure about systems without TSC though.

Something like this? (Warning, will not probably even compile on
x86-64, I do not have 64-bit compiler near me).

static inline void native_io_delay(void)
{
- asm volatile("outb %%al,$0x80" : : : "memory");
+ udelay(8);
}

Alan, did you double-check that 8 us? I tried to but I seem to not have trustworthy documentation.

Rene.
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