[src/trunk]: src/sys/dev/fdt dwcwdt: make this work correctly

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

details:   https://anonhg.NetBSD.org/src/rev/f33667ed5dd4
branches:  trunk
changeset: 460367:f33667ed5dd4
user:      tnn <tnn%NetBSD.org@localhost>
date:      Sat Oct 19 13:08:52 2019 +0000

description:
dwcwdt: make this work correctly

- sysmon_wdog.smw_period is seconds, not milliseconds
- tickle the watchdog before enabling it

diffstat:

 sys/dev/fdt/dwcwdt_fdt.c |  38 ++++++++++++++++++++------------------
 1 files changed, 20 insertions(+), 18 deletions(-)

diffs (87 lines):

diff -r 148f7ad1e3d8 -r f33667ed5dd4 sys/dev/fdt/dwcwdt_fdt.c
--- a/sys/dev/fdt/dwcwdt_fdt.c  Sat Oct 19 12:55:21 2019 +0000
+++ b/sys/dev/fdt/dwcwdt_fdt.c  Sat Oct 19 13:08:52 2019 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: dwcwdt_fdt.c,v 1.3 2018/10/28 15:06:10 aymeric Exp $ */
+/* $NetBSD: dwcwdt_fdt.c,v 1.4 2019/10/19 13:08:52 tnn Exp $ */
 
 /*-
  * Copyright (c) 2018 Jared McNeill <jmcneill%invisible.ca@localhost>
@@ -27,7 +27,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: dwcwdt_fdt.c,v 1.3 2018/10/28 15:06:10 aymeric Exp $");
+__KERNEL_RCSID(0, "$NetBSD: dwcwdt_fdt.c,v 1.4 2019/10/19 13:08:52 tnn Exp $");
 
 #include <sys/param.h>
 #include <sys/bus.h>
@@ -111,8 +111,8 @@
 
        for (i = 0; i < __arraycount(wdt_torr); i++) {
                const u_int ms = (u_int)((((uint64_t)wdt_torr[i] + 1) * 1000) / sc->sc_clkrate);
-               if (ms >= period) {
-                       *aperiod = ms;
+               if (ms >= period * 1000) {
+                       *aperiod = ms / 1000;
                        return i;
                }
        }
@@ -121,14 +121,28 @@
 }
 
 static int
+dwcwdt_tickle(struct sysmon_wdog *smw)
+{
+       struct dwcwdt_softc * const sc = smw->smw_cookie;
+       const uint32_t crr =
+           __SHIFTIN(WDT_CRR_CNT_RESTART_MAGIC, WDT_CRR_CNT_RESTART);
+
+       WR4(sc, WDT_CRR, crr);
+
+       return 0;
+}
+
+static int
 dwcwdt_setmode(struct sysmon_wdog *smw)
 {
        struct dwcwdt_softc * const sc = smw->smw_cookie;
        uint32_t cr, torr;
        int intv;
 
-       if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED)
+       if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
+               /* Watchdog can only be disarmed by a reset */
                return EIO;
+       }
 
        if (smw->smw_period == WDOG_PERIOD_DEFAULT)
                smw->smw_period = DWCWDT_PERIOD_DEFAULT;
@@ -140,7 +154,7 @@
 
        torr = __SHIFTIN(intv, WDT_TORR_TIMEOUT_PERIOD);
        WR4(sc, WDT_TORR, torr);
-
+       dwcwdt_tickle(smw);
        cr = RD4(sc, WDT_CR);
        cr &= ~WDT_CR_RESP_MODE;
        cr |= WDT_CR_WDT_EN;
@@ -150,18 +164,6 @@
 }
 
 static int
-dwcwdt_tickle(struct sysmon_wdog *smw)
-{
-       struct dwcwdt_softc * const sc = smw->smw_cookie;
-       const uint32_t crr =
-           __SHIFTIN(WDT_CRR_CNT_RESTART_MAGIC, WDT_CRR_CNT_RESTART);
-
-       WR4(sc, WDT_CRR, crr);
-
-       return 0;
-}
-
-static int
 dwcwdt_match(device_t parent, cfdata_t cf, void *aux)
 {
        struct fdt_attach_args * const faa = aux;