freebsd-nq/sys/dev/sio
Bruce Evans 160da193e0 Fixes and workarounds for Hayes ESP:
- don't uselessly initialize the fifo "DMA" bit at attach time.
- initialize the fifo "DMA" bit at open time.  Without this, the device
  interrupts for every character received, reducing input performance
  to that of an 8250.
- don't uselessly initialize the fifo trigger level to 8 (scaled to
  256) at attach time.
- don't scale the fifo trigger level to 512 bytes.  The driver's pseudo-
  dma buffer has size 256, so it can't handle bursts of size 512 or 256.
  It should be able to handle the second lowest ftl (2 scaled to 64).
- don't reset the fifos in siostop().  Reset triggers a hardware bug
  involving wedging of the output interrupt bit  This workaround
  unfortunately requires ESP support to be configured.
1997-01-29 21:50:02 +00:00
..
sio.c Fixes and workarounds for Hayes ESP: 1997-01-29 21:50:02 +00:00
sioreg.h Make the long-awaited change from $Id$ to $FreeBSD$ 1997-01-14 07:20:47 +00:00