[src/trunk]: src/sys/dev/pci Fix a couple of problems in the PCscsi-PCI driver:

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

details:   https://anonhg.NetBSD.org/src/rev/ad93b14d9fdd
branches:  trunk
changeset: 472203:ad93b14d9fdd
user:      thorpej <thorpej%NetBSD.org@localhost>
date:      Sun Apr 25 01:20:02 1999 +0000

description:
Fix a couple of problems in the PCscsi-PCI driver:
* resid in pcscp_dma_intr() should also be set in the data out phase.
* Don't set up DMA in the transfer pad operations.
* Change URL of the PDF technical manual to the index page.
* include <machine/bswap.h> on big endian machines.

Fixes timeouts writing large blocks to tapes.  From Izumi Tsutsui,
PR 7252.

diffstat:

 sys/dev/pci/pcscp.c |  28 ++++++++++++++++++++++------
 1 files changed, 22 insertions(+), 6 deletions(-)

diffs (76 lines):

diff -r 522d192196b2 -r ad93b14d9fdd sys/dev/pci/pcscp.c
--- a/sys/dev/pci/pcscp.c       Sun Apr 25 00:10:44 1999 +0000
+++ b/sys/dev/pci/pcscp.c       Sun Apr 25 01:20:02 1999 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: pcscp.c,v 1.2 1999/01/08 19:55:17 thorpej Exp $        */
+/*     $NetBSD: pcscp.c,v 1.3 1999/04/25 01:20:02 thorpej Exp $        */
 
 /*-
  * Copyright (c) 1997, 1998, 1999 The NetBSD Foundation, Inc.
@@ -42,7 +42,7 @@
  * written by Izumi Tsutsui <tsutsui%ceres.dti.ne.jp@localhost>
  *
  * Technical manual available at
- * http://www.amd.com/products/npd/techdocs/19113a.pdf
+ * http://www.amd.com/products/npd/techdocs/techdocs.html
  */
 
 #include <sys/param.h>
@@ -52,6 +52,9 @@
 
 #include <machine/bus.h>
 #include <machine/intr.h>
+#if BYTE_ORDER == BIG_ENDIAN
+#include <machine/bswap.h>
+#endif
 
 #include <dev/scsipi/scsi_all.h>
 #include <dev/scsipi/scsipi_all.h>
@@ -434,13 +437,20 @@
                                (NCR_READ_REG(sc, NCR_TCM) << 8),
                        NCR_READ_REG(sc, NCR_TCL),
                        NCR_READ_REG(sc, NCR_TCM)));
-               WRITE_DMAREG(esc, DMA_CMD, DMACMD_IDLE |
-                            (datain ? DMACMD_DIR : 0));
-               bus_dmamap_unload(esc->sc_dmat, dmap);
                return 0;
        }
 
        resid = 0;
+       /*
+        * If a transfer onto the SCSI bus gets interrupted by the device
+        * (e.g. for a SAVEPOINTER message), the data in the FIFO counts
+        * as residual since the ESP counter registers get decremented as
+        * bytes are clocked into the FIFO.
+        */
+       if (!datain &&
+           (resid = (NCR_READ_REG(sc, NCR_FFLAG) & NCRFIFO_FF)) != 0) {
+               NCR_DMA(("pcscp_dma_intr: empty esp FIFO of %d ", resid));
+       }
 
        if ((sc->sc_espstat & NCRSTAT_TC) == 0) {
                /*
@@ -555,9 +565,11 @@
 #endif
 
        /*
-        * XXX should handle `Transfer Pad' operation?
+        * No need to set up DMA in `Transfer Pad' operation.
         * (case of *dmasize == 0)
         */
+       if (*dmasize == 0)
+               return 0;
 
        error = bus_dmamap_load(esc->sc_dmat, dmap, *esc->sc_dmaaddr,
                                *esc->sc_dmalen, NULL,
@@ -631,6 +643,10 @@
        bus_dmamap_t dmap = esc->sc_xfermap, mdldmap = esc->sc_mdldmap;
        int datain = esc->sc_datain;
 
+       /* No DMA transfer in Transfer Pad operation */
+       if (esc->sc_dmasize == 0)
+               return;
+
        /* sync transfer buffer */
        bus_dmamap_sync(esc->sc_dmat, dmap, 0, dmap->dm_mapsize,
                        datain ? BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);