CVS commit: src/sys/dev/ic

["Taylor R Campbell" <riastradh%netbsd.org@localhost>]

Module Name:    src
Committed By:   riastradh
Date:           Thu Nov 17 23:57:21 UTC 2022

Modified Files:
        src/sys/dev/ic: pckbc.c

Log Message:
pckbc(4): Stop waiting 8us before reading each data byte.

This appears to have copied from pccons(4), where it was introduced
by mycroft@ in 1994 in sys/arch/i386/isa/pccons.c rev. 1.63 with the
commit message `Rename two files.'.  No justification was given.

This delay was in a hard interrupt handler, and an MP-unsafe one to
boot, so it could hold up system responsiveness by delaying interrupt
handling and blocking other users of the legacy kernel lock.

The delay remains in the pckbc_wait_output loop to set a command
byte, which is not used in the interrupt path (and I suspect is used
only on boot during attach anyway).


To generate a diff of this commit:
cvs rdiff -u -r1.64 -r1.65 src/sys/dev/ic/pckbc.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.