hw/watchdog/cmsdk-apb-watchdog: Convert to use Clock input

Switch the CMSDK APB watchdog device over to using its Clock input;
the wdogclk_frq property is now ignored.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Luc Michel <luc@lmichel.fr>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20210128114145.20536-21-peter.maydell@linaro.org
Message-id: 20210121190622.22000-21-peter.maydell@linaro.org

hw/watchdog/cmsdk-apb-watchdog.c

@@ -310,6 +310,15 @@ static void cmsdk_apb_watchdog_reset(DeviceState *dev)
     ptimer_transaction_commit(s->timer);
 }
 
+static void cmsdk_apb_watchdog_clk_update(void *opaque)
+{
+    CMSDKAPBWatchdog *s = CMSDK_APB_WATCHDOG(opaque);
+
+    ptimer_transaction_begin(s->timer);
+    ptimer_set_period_from_clock(s->timer, s->wdogclk, 1);
+    ptimer_transaction_commit(s->timer);
+}
+
 static void cmsdk_apb_watchdog_init(Object *obj)
 {
     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
@@ -319,7 +328,8 @@ static void cmsdk_apb_watchdog_init(Object *obj)
                           s, "cmsdk-apb-watchdog", 0x1000);
     sysbus_init_mmio(sbd, &s->iomem);
     sysbus_init_irq(sbd, &s->wdogint);
-    s->wdogclk = qdev_init_clock_in(DEVICE(s), "WDOGCLK", NULL, NULL);
+    s->wdogclk = qdev_init_clock_in(DEVICE(s), "WDOGCLK",
+                                    cmsdk_apb_watchdog_clk_update, s);
 
     s->is_luminary = false;
     s->id = cmsdk_apb_watchdog_id;
@@ -329,9 +339,9 @@ static void cmsdk_apb_watchdog_realize(DeviceState *dev, Error **errp)
 {
     CMSDKAPBWatchdog *s = CMSDK_APB_WATCHDOG(dev);
 
-    if (s->wdogclk_frq == 0) {
+    if (!clock_has_source(s->wdogclk)) {
         error_setg(errp,
-                   "CMSDK APB watchdog: wdogclk-frq property must be set");
+                   "CMSDK APB watchdog: WDOGCLK clock must be connected");
         return;
     }
 
@@ -342,7 +352,7 @@ static void cmsdk_apb_watchdog_realize(DeviceState *dev, Error **errp)
                            PTIMER_POLICY_NO_COUNTER_ROUND_DOWN);
 
     ptimer_transaction_begin(s->timer);
-    ptimer_set_freq(s->timer, s->wdogclk_frq);
+    ptimer_set_period_from_clock(s->timer, s->wdogclk, 1);
     ptimer_transaction_commit(s->timer);
 }