[src/trunk]: src/sys/dev/pci Add a comment clarifying why we clear TWEF_AEN i...

[thorpej <thorpej%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/b04a1f10413c
branches:  trunk
changeset: 552360:b04a1f10413c
user:      thorpej <thorpej%NetBSD.org@localhost>
date:      Tue Sep 23 23:10:53 2003 +0000

description:
Add a comment clarifying why we clear TWEF_AEN in twe_reset() now.

diffstat:

 sys/dev/pci/twe.c |  11 +++++++++--
 1 files changed, 9 insertions(+), 2 deletions(-)

diffs (32 lines):

diff -r d8fa162cdb29 -r b04a1f10413c sys/dev/pci/twe.c
--- a/sys/dev/pci/twe.c Tue Sep 23 23:10:08 2003 +0000
+++ b/sys/dev/pci/twe.c Tue Sep 23 23:10:53 2003 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: twe.c,v 1.47 2003/09/23 23:08:54 thorpej Exp $ */
+/*     $NetBSD: twe.c,v 1.48 2003/09/23 23:10:53 thorpej Exp $ */
 
 /*-
  * Copyright (c) 2000, 2001, 2002, 2003 The NetBSD Foundation, Inc.
@@ -70,7 +70,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: twe.c,v 1.47 2003/09/23 23:08:54 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: twe.c,v 1.48 2003/09/23 23:10:53 thorpej Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -653,6 +653,13 @@
         * Pull AENs out of the controller; look for a soft reset AEN.
         * Open code this, since we want to detect reset even if the
         * queue for management tools is full.
+        *
+        * Note that since:
+        *      - interrupts are blocked
+        *      - we have reset the controller
+        *      - acknowledged the pending ATTENTION
+        * that there is no way a pending asynchronous AEN fetch would
+        * finish, so clear the flag.
         */
        sc->sc_flags &= ~TWEF_AEN;
        for (got = 0;;) {