Re: Can we kill f inb_p, outb_p and other random I/O on port 0x80, in 2.6?

[bill davidsen]

In article <20030922182808.GA28372@xxxxxxxxxxxxxxxxxx>,
Jamie Lokier  <jamie@xxxxxxxxxxxxx> wrote:
| Arjan van de Ven wrote:
| > The first person to complain about the extra branch miss in udelay for
| > this will get laughed at by me ;)
| 
| udelay(1) is too slow on a 386 even without the branch miss.
| 
| If you think I/O operations are infinitely slower than other
| instructions, please explain why there is asm-optimised I/O code in
| asm-i386/floppy.h.
| 
| :)

The choices are:
1 - there really were some old crappy chips which were both slow and
    timing sensitive
2 - someone thought that would optimize access
3 - gcc of the time generated bad code if you didn't

-- 
bill davidsen <davidsen@xxxxxxx>
  CTO, TMR Associates, Inc
Doing interesting things with little computers since 1979.
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