[src/trunk]: src/sys/arch/mac68k Introduce a flag to disable PDMA when writing.

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

details:   https://anonhg.NetBSD.org/src/rev/cf5880119773
branches:  trunk
changeset: 373572:cf5880119773
user:      nat <nat%NetBSD.org@localhost>
date:      Sat Feb 18 13:28:05 2023 +0000

description:
Introduce a flag to disable PDMA when writing.

The use of pdma when writing would always cause a panic on my Powerbook 160,
possibly others as well.

As posted to tech-kern.

diffstat:

 sys/arch/mac68k/conf/GENERICSBC |   9 +++++----
 sys/arch/mac68k/conf/INSTALLSBC |   9 +++++----
 sys/arch/mac68k/dev/sbc.c       |   5 +++--
 sys/arch/mac68k/dev/sbcvar.h    |  13 +++++++------
 4 files changed, 20 insertions(+), 16 deletions(-)

diffs (95 lines):

diff -r 64cd3c016f7f -r cf5880119773 sys/arch/mac68k/conf/GENERICSBC
--- a/sys/arch/mac68k/conf/GENERICSBC   Sat Feb 18 13:17:45 2023 +0000
+++ b/sys/arch/mac68k/conf/GENERICSBC   Sat Feb 18 13:28:05 2023 +0000
@@ -1,4 +1,4 @@
-# $NetBSD: GENERICSBC,v 1.56 2008/03/27 20:00:24 hauke Exp $
+# $NetBSD: GENERICSBC,v 1.57 2023/02/18 13:28:05 nat Exp $
 #
 # GENERICSBC machine description file
 
@@ -12,7 +12,8 @@
 
 no ncrscsi0                            # SCSI NCR 5380
 
-# SBC_PDMA      0x01    Use PDMA for polled transfers
-# SBC_INTR      0x02    Allow SCSI IRQ/DRQ interrupts
-# SBC_RESELECT  0x04    Allow disconnect/reselect
+# SBC_PDMA             0x01    Use PDMA for polled transfers
+# SBC_INTR             0x02    Allow SCSI IRQ/DRQ interrupts
+# SBC_RESELECT         0x04    Allow disconnect/reselect
+# SBC_PDMA_NO_WRITE    0x08    Disallow PDMA for writing
 sbc0   at obio? addr 0 flags 0x1       # MI SCSI NCR 5380
diff -r 64cd3c016f7f -r cf5880119773 sys/arch/mac68k/conf/INSTALLSBC
--- a/sys/arch/mac68k/conf/INSTALLSBC   Sat Feb 18 13:17:45 2023 +0000
+++ b/sys/arch/mac68k/conf/INSTALLSBC   Sat Feb 18 13:28:05 2023 +0000
@@ -1,4 +1,4 @@
-# $NetBSD: INSTALLSBC,v 1.32 2008/03/27 20:00:24 hauke Exp $
+# $NetBSD: INSTALLSBC,v 1.33 2023/02/18 13:28:05 nat Exp $
 #
 # INSTALLSBC machine description file
 
@@ -12,7 +12,8 @@
 
 no ncrscsi0                            # SCSI NCR 5380
 
-# SBC_PDMA      0x01    Use PDMA for polled transfers
-# SBC_INTR      0x02    Allow SCSI IRQ/DRQ interrupts
-# SBC_RESELECT  0x04    Allow disconnect/reselect
+# SBC_PDMA             0x01    Use PDMA for polled transfers
+# SBC_INTR             0x02    Allow SCSI IRQ/DRQ interrupts
+# SBC_RESELECT         0x04    Allow disconnect/reselect
+# SBC_PDMA_NO_WRITE    0x08    Disallow PDMA for writing
 sbc0   at obio? addr 0 flags 0x1       # MI SCSI NCR 5380
diff -r 64cd3c016f7f -r cf5880119773 sys/arch/mac68k/dev/sbc.c
--- a/sys/arch/mac68k/dev/sbc.c Sat Feb 18 13:17:45 2023 +0000
+++ b/sys/arch/mac68k/dev/sbc.c Sat Feb 18 13:28:05 2023 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: sbc.c,v 1.58 2023/02/18 13:17:45 nat Exp $     */
+/*     $NetBSD: sbc.c,v 1.59 2023/02/18 13:28:05 nat Exp $     */
 
 /*
  * Copyright (C) 1996 Scott Reynolds.  All rights reserved.
@@ -45,7 +45,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: sbc.c,v 1.58 2023/02/18 13:17:45 nat Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sbc.c,v 1.59 2023/02/18 13:28:05 nat Exp $");
 
 #include "opt_ddb.h"
 
@@ -318,6 +318,7 @@
 
        if (datalen < ncr_sc->sc_min_dma_len ||
            (sc->sc_options & SBC_PDMA) == 0 ||
+           (sc->sc_options & SBC_PDMA_NO_WRITE) ||
            (ncr_sc->sc_current != NULL &&
            (ncr_sc->sc_current->sr_xs->xs_control & XS_CTL_POLL)))
                return ncr5380_pio_out(ncr_sc, phase, datalen, data);
diff -r 64cd3c016f7f -r cf5880119773 sys/arch/mac68k/dev/sbcvar.h
--- a/sys/arch/mac68k/dev/sbcvar.h      Sat Feb 18 13:17:45 2023 +0000
+++ b/sys/arch/mac68k/dev/sbcvar.h      Sat Feb 18 13:28:05 2023 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: sbcvar.h,v 1.12 2005/12/11 12:18:02 christos Exp $     */
+/*     $NetBSD: sbcvar.h,v 1.13 2023/02/18 13:28:05 nat Exp $  */
 
 /*
  * Copyright (C) 1996 Scott Reynolds.  All rights reserved.
@@ -77,11 +77,12 @@
  * The options code is based on the sparc 'si' driver's version of
  * the same.
  */     
-#define        SBC_PDMA        0x01    /* Use PDMA for polled transfers */
-#define        SBC_INTR        0x02    /* Allow SCSI IRQ/DRQ interrupts */
-#define        SBC_RESELECT    0x04    /* Allow disconnect/reselect */
-#define        SBC_OPTIONS_MASK        (SBC_RESELECT|SBC_INTR|SBC_PDMA)
-#define        SBC_OPTIONS_BITS        "\10\3RESELECT\2INTR\1PDMA"
+#define        SBC_PDMA                0x01    /* Use PDMA for polled transfers */
+#define        SBC_INTR                0x02    /* Allow SCSI IRQ/DRQ interrupts */
+#define        SBC_RESELECT            0x04    /* Allow disconnect/reselect */
+#define        SBC_PDMA_NO_WRITE       0x08    /* No PDMA for writes */
+#define        SBC_OPTIONS_MASK (SBC_PDMA_NO_WRITE|SBC_RESELECT|SBC_INTR|SBC_PDMA)
+#define        SBC_OPTIONS_BITS        "\10\4NOWRITE3RESELECT\2INTR\1PDMA"
 
 extern int     sbc_debug;
 extern int     sbc_link_flags;