What is the prefered way to do a delay for code that (might) run(s) during
autoconfiguration? The case at hand is dev/sun/kbsun.c that needs to wait
for the keyboard to reset before reading the keyboard type. It uses
this code:

        /* the wakeup for this is in kbd_was_reset(). */
        error = tsleep((caddr_t)&ks->kbd_id, PZERO | PCATCH, devopn, hz);

While cold, the (l)tsleep does only bounce spl to give interrupts a chance,
but does not cause any serious delay.

Now there are several ways to work around/fix this:

 1) remove the wakeup, adjust spl() and just turn the tsleep into a delay(),
    then restore spl.
 2) change the wakeup into some flag setting and do a loop
    around short delay() calls, adjusting spl before and after
    as above
 3) change ltsleep() for the cold case and insert a delay if it's timo
    arg is non-zero
 4) make ltsleep realy work, even if cold (using a global flag and
    a loop around short delays, and having wakeup set the global flag)


Any thoughts?

Martin
(Thanks to John for analyzing the problem)