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

H. Peter Anvin
2007-12-11T01:30:26Z

David Newall wrote:
> Where did the 8us delay come from? The documentation and source is
> careful not to say how long the delay is. Would changing it to, say
> 1us, be technically wrong? Is code that requires 8us correct?

I think a single ISA bus transaction is 1 µs, so two of them back to
back should be 2 µs, not 8 µs...

-hpa