[src/trunk]: src/sys/arch/sandpoint/stand/netboot - make sure to wait for BUS...

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

details:   https://anonhg.NetBSD.org/src/rev/7c54d3e1bf18
branches:  trunk
changeset: 761247:7c54d3e1bf18
user:      nisimura <nisimura%NetBSD.org@localhost>
date:      Sat Jan 22 00:32:41 2011 +0000

description:
- make sure to wait for BUSY bit goes down prior to each 512B block
read from xfer register, or corrupted datum may be retrieved.  Uncovered
by corrected PIO READ_CMD value.
- remove redundant register assignments to set transfer mode.

diffstat:

 sys/arch/sandpoint/stand/netboot/dsk.c |  41 +++++++++++++++++++--------------
 1 files changed, 23 insertions(+), 18 deletions(-)

diffs (101 lines):

diff -r f160f4b6a63a -r 7c54d3e1bf18 sys/arch/sandpoint/stand/netboot/dsk.c
--- a/sys/arch/sandpoint/stand/netboot/dsk.c    Fri Jan 21 23:36:49 2011 +0000
+++ b/sys/arch/sandpoint/stand/netboot/dsk.c    Sat Jan 22 00:32:41 2011 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: dsk.c,v 1.7 2011/01/11 07:01:21 nisimura Exp $ */
+/* $NetBSD: dsk.c,v 1.8 2011/01/22 00:32:41 nisimura Exp $ */
 
 /*-
  * Copyright (c) 2010 The NetBSD Foundation, Inc.
@@ -154,7 +154,9 @@
        (void)CSR_READ_1(chan->alt);
 
        sts = CSR_READ_1(chan->cmd + _STS);
-       while (milli-- > 0 && sts != 0xff && (sts & ATA_STS_BUSY)) {
+       while (milli-- > 0
+           && sts != 0xff
+           && (sts & (ATA_STS_BUSY|ATA_STS_DRDY)) != ATA_STS_DRDY) {
                delay(1000);
                sts = CSR_READ_1(chan->cmd + _STS);
        }
@@ -166,6 +168,8 @@
                msg = "returned ERR";
        else if (sts & ATA_STS_BUSY)
                msg = "remains BUSY";
+       else if ((sts & ATA_STS_DRDY) == 0)
+               msg = "no DRDY";
 
        if (err != NULL)
                *err = msg;
@@ -251,10 +255,10 @@
                huge = p[60] | (p[61] << 16);
        }
        if ((p[83] & 0xc000) == 0x4000 && (p[83] & (1 << 10))) {
+               printf("LBA48 ");
                huge = p[100] | (p[101] << 16);
                huge |= (uint64_t)p[102] << 32;
                huge |= (uint64_t)p[103] << 48;
-               printf("LBA48 ");
        }
        huge >>= (1 + 10);
        printf("%d MB\n", (int)huge);
@@ -357,10 +361,7 @@
 
        CSR_WRITE_1(chan->cmd + _FEA, ATA_XFER);
        CSR_WRITE_1(chan->cmd + _NSECT, XFER_PIO0);
-       CSR_WRITE_1(chan->cmd + _LBAL, 0);
-       CSR_WRITE_1(chan->cmd + _LBAM, 0);
-       CSR_WRITE_1(chan->cmd + _LBAH, 0);
-       CSR_WRITE_1(chan->cmd + _DEV, ATA_DEV_OBS);
+       CSR_WRITE_1(chan->cmd + _DEV, ATA_DEV_OBS); /* ??? */
        CSR_WRITE_1(chan->cmd + _CMD, ATA_CMD_SETF);
 
        spinwait_unbusy(l, n, 1000, NULL);
@@ -372,7 +373,7 @@
        struct dkdev_ata *l;
        struct dvata_chan *chan;
        void (*issue)(struct dvata_chan *, uint64_t, uint32_t);
-       int n, rdcnt, i;
+       int n, rdcnt, i, k;
        uint16_t *p;
        const char *err;
        int error;
@@ -386,16 +387,20 @@
                issue = (bno < (1ULL<<28)) ? issue28 : issue48;
                rdcnt = (bcnt > 255) ? 255 : bcnt;
                (*issue)(chan, bno, rdcnt);
-               if (spinwait_unbusy(l, n, 1000, &err) == 0) {
-                       printf("%s blk %d %s\n", d->xname, (int)bno, err);
-                       error = EIO;
-                       continue;
+               for (k = 0; k < rdcnt; k++) {
+                       if (spinwait_unbusy(l, n, 1000, &err) == 0) {
+                               printf("%s blk %d %s\n",
+                                  d->xname, (int)bno, err);
+                               error = EIO;
+                               break;
+                       }
+                       for (i = 0; i < 512; i += 2) {
+                               /* arrives in native order */
+                               *p++ = *(uint16_t *)(chan->cmd + _DAT);
+                       }
+                       /* clear irq if any */
+                       (void)CSR_READ_1(chan->cmd + _STS);
                }
-               for (i = 0; i < rdcnt * 512; i += 2) {
-                       /* arrives in native order */
-                       *p++ = *(uint16_t *)(chan->cmd + _DAT);
-               }
-               (void)CSR_READ_1(chan->cmd + _STS);
        }
        return error;
 }
@@ -404,7 +409,7 @@
 issue48(struct dvata_chan *chan, uint64_t bno, uint32_t nblk)
 {
 
-       CSR_WRITE_1(chan->cmd + _NSECT, 0);
+       CSR_WRITE_1(chan->cmd + _NSECT, 0); /* always less than 256 */
        CSR_WRITE_1(chan->cmd + _LBAL, (bno >> 24) & 0xff);
        CSR_WRITE_1(chan->cmd + _LBAM, (bno >> 32) & 0xff);
        CSR_WRITE_1(chan->cmd + _LBAH, (bno >> 40) & 0xff);