[src/trunk]: src/sys/dev/ic Revert to polling for ata_get_params() in wdc_cha...

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

details:   https://anonhg.NetBSD.org/src/rev/478eab9e8faf
branches:  trunk
changeset: 552939:478eab9e8faf
user:      bouyer <bouyer%NetBSD.org@localhost>
date:      Mon Oct 06 21:51:31 2003 +0000

description:
Revert to polling for ata_get_params() in wdc_channel_attach().
When probing a nonexistent slave, we may timeout waiting for an interrupt.
In __wdccommand_start(), for polled data in commands, abort quickly if
status still read 0 after 400ns (for a nonexistant slave, the
command will either be aborted, or the status register will report 0; for
a real device we should have BSY, DRQ or ERR).
Thanks to Alexander Yurchenko for reporting the problem and testing the
fix.

diffstat:

 sys/dev/ic/wdc.c |  39 ++++++++++++++++++++++++---------------
 1 files changed, 24 insertions(+), 15 deletions(-)

diffs (91 lines):

diff -r 5ccd882412e3 -r 478eab9e8faf sys/dev/ic/wdc.c
--- a/sys/dev/ic/wdc.c  Mon Oct 06 21:40:32 2003 +0000
+++ b/sys/dev/ic/wdc.c  Mon Oct 06 21:51:31 2003 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: wdc.c,v 1.134 2003/09/25 19:29:49 mycroft Exp $ */
+/*     $NetBSD: wdc.c,v 1.135 2003/10/06 21:51:31 bouyer Exp $ */
 
 /*
  * Copyright (c) 1998, 2001 Manuel Bouyer.  All rights reserved.
@@ -70,7 +70,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: wdc.c,v 1.134 2003/09/25 19:29:49 mycroft Exp $");
+__KERNEL_RCSID(0, "$NetBSD: wdc.c,v 1.135 2003/10/06 21:51:31 bouyer Exp $");
 
 #ifndef WDCDEBUG
 #define WDCDEBUG
@@ -427,11 +427,12 @@
                 * Then issue a IDENTIFY command, to try to detect slave ghost
                 */
                delay(5000);
-               error = ata_get_params(&chp->ch_drive[i], AT_WAIT, &params);
+               error = ata_get_params(&chp->ch_drive[i],
+                   AT_POLL, &params);
                if (error != CMD_OK) {
                        delay(1000000);
-                       error = ata_get_params(&chp->ch_drive[i], AT_WAIT,
-                           &params);
+                       error = ata_get_params(&chp->ch_drive[i],
+                           AT_POLL, &params);
                }
                if (error == CMD_OK) {
                        /* If IDENTIFY succeded, this is not an OLD ctrl */
@@ -1414,6 +1415,7 @@
 {   
        int drive = xfer->drive;
        struct wdc_command *wdc_c = xfer->cmd;
+       int st;
 
        WDCDEBUG_PRINT(("__wdccommand_start %s:%d:%d\n",
            chp->wdc->sc_dev.dv_xname, chp->channel, xfer->drive),
@@ -1430,24 +1432,26 @@
                __wdccommand_done(chp, xfer);
                return;
        }
+       if (wdc_c->flags & AT_POLL) {
+               /* polled command, disable interrupts */
+               bus_space_write_1(chp->ctl_iot, chp->ctl_ioh, wd_aux_ctlr,
+                   WDCTL_4BIT | WDCTL_IDS);
+       }
        wdccommand(chp, drive, wdc_c->r_command, wdc_c->r_cyl, wdc_c->r_head,
            wdc_c->r_sector, wdc_c->r_count, wdc_c->r_precomp);
-#if 0
-       if (wdc_c->r_command == WDCC_IDENTIFY) {
+       if ((wdc_c->flags & (AT_POLL | AT_READ)) == (AT_POLL | AT_READ)) {
                /*
-                * This is an IDENTIFY command.  Do an immediate poll of the
-                * status to try to determine if there's actually a device
-                * there.  Since this is a data-bearing command, it should go
-                * to either BSY or DRQ within 400ns.
+                * This is a data in command, so we should have either
+                * BSY or DRQ in 400ns, or error.
                 */
                delay(10);      /* 400ns delay */
-               if ((bus_space_read_1(chp->ctl_iot, chp->ctl_ioh, wd_aux_altsts) &
-                   (WDCS_BSY | WDCS_DRQ | WDCS_ERR)) == 0) {
-                       __wdccommand_intr(chp, xfer, 0);
+               st = bus_space_read_1(chp->cmd_iot, chp->cmd_ioh, wd_status);
+               if (st == 0) {
+                       wdc_c->flags |= AT_TIMEOU;
+                       __wdccommand_done(chp, xfer);
                        return;
                }
        }
-#endif
        if ((wdc_c->flags & AT_POLL) == 0) {
                chp->ch_flags |= WDCF_IRQ_WAIT; /* wait for interrupt */
                callout_reset(&chp->ch_callout, wdc_c->timeout / 1000 * hz,
@@ -1579,6 +1583,11 @@
                wdc_c->r_precomp = bus_space_read_1(chp->cmd_iot, chp->cmd_ioh,
                                                    wd_precomp);
        }
+       if (wdc_c->flags & AT_POLL) {
+               /* enable interrupts */
+               bus_space_write_1(chp->ctl_iot, chp->ctl_ioh, wd_aux_ctlr,
+                   WDCTL_4BIT);
+       }
        wdc_free_xfer(chp, xfer);
        if (wdc_c->flags & AT_WAIT)
                wakeup(wdc_c);