[src/trunk]: src/sys/dev/ic Fix a wrong calculation bug around RX ring buffer...

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

details:   https://anonhg.NetBSD.org/src/rev/c852eda7173c
branches:  trunk
changeset: 752363:c852eda7173c
user:      tsutsui <tsutsui%NetBSD.org@localhost>
date:      Wed Feb 24 13:10:26 2010 +0000

description:
Fix a wrong calculation bug around RX ring buffer memory address
slipped in about sixteen years ago.  Fortunately, it had been working
for ages because some devices used address zero and other devices
ignored wrong higher bits.

Tested on we(4) (SMC Elite Ultra) and ne(4) (NE2000 compatible
named UL0001) on ISA.
Note FreeBSD also uses the same correct value in their ed(4) driver.

diffstat:

 sys/dev/ic/dp8390.c |  7 ++++---
 1 files changed, 4 insertions(+), 3 deletions(-)

diffs (28 lines):

diff -r 5cb621479a57 -r c852eda7173c sys/dev/ic/dp8390.c
--- a/sys/dev/ic/dp8390.c       Wed Feb 24 13:02:13 2010 +0000
+++ b/sys/dev/ic/dp8390.c       Wed Feb 24 13:10:26 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: dp8390.c,v 1.73 2010/01/19 22:06:24 pooka Exp $        */
+/*     $NetBSD: dp8390.c,v 1.74 2010/02/24 13:10:26 tsutsui Exp $      */
 
 /*
  * Device driver for National Semiconductor DS8390/WD83C690 based ethernet
@@ -14,7 +14,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: dp8390.c,v 1.73 2010/01/19 22:06:24 pooka Exp $");
+__KERNEL_RCSID(0, "$NetBSD: dp8390.c,v 1.74 2010/02/24 13:10:26 tsutsui Exp $");
 
 #include "opt_ipkdb.h"
 #include "opt_inet.h"
@@ -114,7 +114,8 @@
        sc->tx_page_start = sc->mem_start >> ED_PAGE_SHIFT;
        sc->rec_page_start = sc->tx_page_start + sc->txb_cnt * ED_TXBUF_SIZE;
        sc->rec_page_stop = sc->tx_page_start + (sc->mem_size >> ED_PAGE_SHIFT);
-       sc->mem_ring = sc->mem_start + (sc->rec_page_start << ED_PAGE_SHIFT);
+       sc->mem_ring = sc->mem_start +
+           ((sc->txb_cnt * ED_TXBUF_SIZE) << ED_PAGE_SHIFT);
        sc->mem_end = sc->mem_start + sc->mem_size;
 
        /* Now zero memory and verify that it is clear. */