clock: Add ClockEvent parameter to callbacks

The Clock framework allows users to specify a callback which is
called after the clock's period has been updated.  Some users need to
also have a callback which is called before the clock period is
updated.

As the first step in adding support for notifying Clock users on
pre-update events, add an argument to the ClockCallback to specify
what event is being notified, and add an argument to the various
functions for registering a callback to specify which events are
of interest to that callback.

Note that the documentation update renders correct the previously
incorrect claim in 'Adding a new clock' that callbacks "will be
explained in a following section".

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>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210219144617.4782-2-peter.maydell@linaro.org

1 files changed, 5 insertions, 4 deletions

diff --git a/hw/arm/armsse.c b/hw/arm/armsse.c
index 26e1a8c95b..fa155b7202 100644
--- a/hw/arm/armsse.c
+++ b/hw/arm/armsse.c
@@ -230,9 +230,10 @@ static void armsse_forward_sec_resp_cfg(ARMSSE *s)
     qdev_connect_gpio_out(dev_splitter, 2, s->sec_resp_cfg_in);
 }
 
-static void armsse_mainclk_update(void *opaque)
+static void armsse_mainclk_update(void *opaque, ClockEvent event)
 {
     ARMSSE *s = ARM_SSE(opaque);
+
     /*
      * Set system_clock_scale from our Clock input; this is what
      * controls the tick rate of the CPU SysTick timer.
@@ -251,8 +252,8 @@ static void armsse_init(Object *obj)
     assert(info->num_cpus <= SSE_MAX_CPUS);
 
     s->mainclk = qdev_init_clock_in(DEVICE(s), "MAINCLK",
-                                    armsse_mainclk_update, s);
-    s->s32kclk = qdev_init_clock_in(DEVICE(s), "S32KCLK", NULL, NULL);
+                                    armsse_mainclk_update, s, ClockUpdate);
+    s->s32kclk = qdev_init_clock_in(DEVICE(s), "S32KCLK", NULL, NULL, 0);
 
     memory_region_init(&s->container, obj, "armsse-container", UINT64_MAX);
 
@@ -1120,7 +1121,7 @@ static void armsse_realize(DeviceState *dev, Error **errp)
     sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->container);
 
     /* Set initial system_clock_scale from MAINCLK */
-    armsse_mainclk_update(s);
+    armsse_mainclk_update(s, ClockUpdate);
 }
 
 static void armsse_idau_check(IDAUInterface *ii, uint32_t address,