The default methods are overriden to add the activation/deactivation
of the memory regions according to the gating state: Regions are
enabled only when powered and clocked.
As powering-up triggers a reset call, memory regions should
be reset in specialized sysbus devices.
Signed-off-by: Damien Hedde <damien.he...@greensocs.com>
---
include/hw/sysbus.h | 3 +++
hw/core/sysbus.c | 39 +++++++++++++++++++++++++++++++++++++++
2 files changed, 42 insertions(+)
diff --git a/include/hw/sysbus.h b/include/hw/sysbus.h
index 0b59a3b8d6..e17165e78f 100644
--- a/include/hw/sysbus.h
+++ b/include/hw/sysbus.h
@@ -59,6 +59,9 @@ typedef struct SysBusDeviceClass {
*/
char *(*explicit_ofw_unit_address)(const SysBusDevice *dev);
void (*connect_irq_notifier)(SysBusDevice *dev, qemu_irq irq);
+
+ DeviceGatingUpdate parent_power_update;
+ DeviceGatingUpdate parent_clock_update;
} SysBusDeviceClass;
struct SysBusDevice {
diff --git a/hw/core/sysbus.c b/hw/core/sysbus.c
index 3c8e53b188..4a2dfbe907 100644
--- a/hw/core/sysbus.c
+++ b/hw/core/sysbus.c
@@ -325,6 +325,39 @@ MemoryRegion *sysbus_address_space(SysBusDevice *dev)
return get_system_memory();
}
+/*
+ * Action take on power or clock update.
+ */
+static void sysbus_device_gating_update(DeviceState *dev)
+{
+ SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
+ int i;
+
+ for (i = 0;; i++) {
+ MemoryRegion *mr = sysbus_mmio_get_region(sbd, i);
+ if (!mr) {
+ break;
+ }
+ memory_region_set_enabled(mr, dev->powered && dev->clocked);
+ }
+}
+
+/*
+ * Action take on power update.
+ *
+ * Call parent method before doing local action.
+ * So that we override any action taken in parent method (eg if reset
+ * is called due to leaving OFF state)
+ */
+static void sysbus_device_power_update(DeviceState *dev)
+{
+ SysBusDeviceClass *sbdk = SYS_BUS_DEVICE_GET_CLASS(dev);
+
+ sbdk->parent_power_update(dev);
+
+ sysbus_device_gating_update(dev);
+}
+
static void sysbus_device_class_init(ObjectClass *klass, void *data)
{
DeviceClass *k = DEVICE_CLASS(klass);
@@ -341,6 +374,12 @@ static void sysbus_device_class_init(ObjectClass *klass,
void *data)
* subclass needs to override it and set user_creatable=true.
*/
k->user_creatable = false;
+
+ SysBusDeviceClass *sbdk = SYS_BUS_DEVICE_CLASS(klass);
+ device_class_set_parent_power_update(k,
+ sysbus_device_power_update, &sbdk->parent_power_update);
+ device_class_set_parent_clock_update(k,
+ sysbus_device_gating_update, &sbdk->parent_clock_update);
}
static const TypeInfo sysbus_device_type_info = {
--
2.18.0
