platform-bus-device: use device plug callback instead of machine_done notifier

platform-bus were using machine_done notifier to get and map
(assign irq/mmio resources) dynamically added sysbus devices
after all '-device' options had been processed.
That however creates non obvious dependencies on ordering of
machine_done notifiers and requires carefull line juggling
to keep it working. For example see comment above
create_platform_bus() and 'straitforward' arm_load_kernel()
had to converted to machine_done notifier and that lead to
yet another machine_done notifier to keep it working
arm_register_platform_bus_fdt_creator().

Instead of hiding resource assignment in platform-bus-device
to magically initialize sysbus devices, use device plug
callback and assign resources explicitly at board level
at the moment each -device option is being processed.

That adds a bunch of machine declaration boiler plate to
e500plat board, similar to ARM/x86 but gets rid of hidden
machine_done notifier and would allow to remove the dependent
notifiers in ARM code simplifying it and making code flow
easier to follow.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Message-id: 1525691524-32265-3-git-send-email-imammedo@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 5 insertions, 24 deletions

diff --git a/hw/core/platform-bus.c b/hw/core/platform-bus.c
index 33d32fbf22..807cb5ccda 100644
--- a/hw/core/platform-bus.c
+++ b/hw/core/platform-bus.c
@@ -103,7 +103,6 @@ static void plaform_bus_refresh_irqs(PlatformBusDevice *pbus)
 {
     bitmap_zero(pbus->used_irqs, pbus->num_irqs);
     foreach_dynamic_sysbus_device(platform_bus_count_irqs, pbus);
-    pbus->done_gathering = true;
 }
 
 static void platform_bus_map_irq(PlatformBusDevice *pbus, SysBusDevice *sbdev,
@@ -163,12 +162,11 @@ static void platform_bus_map_mmio(PlatformBusDevice *pbus, SysBusDevice *sbdev,
 }
 
 /*
- * For each sysbus device, look for unassigned IRQ lines as well as
- * unassociated MMIO regions. Connect them to the platform bus if available.
+ * Look for unassigned IRQ lines as well as unassociated MMIO regions.
+ * Connect them to the platform bus if available.
  */
-static void link_sysbus_device(SysBusDevice *sbdev, void *opaque)
+void platform_bus_link_device(PlatformBusDevice *pbus, SysBusDevice *sbdev)
 {
-    PlatformBusDevice *pbus = opaque;
     int i;
 
     for (i = 0; sysbus_has_irq(sbdev, i); i++) {
@@ -180,19 +178,6 @@ static void link_sysbus_device(SysBusDevice *sbdev, void *opaque)
     }
 }
 
-static void platform_bus_init_notify(Notifier *notifier, void *data)
-{
-    PlatformBusDevice *pb = container_of(notifier, PlatformBusDevice, notifier);
-
-    /*
-     * Generate a bitmap of used IRQ lines, as the user might have specified
-     * them on the command line.
-     */
-    plaform_bus_refresh_irqs(pb);
-
-    foreach_dynamic_sysbus_device(link_sysbus_device, pb);
-}
-
 static void platform_bus_realize(DeviceState *dev, Error **errp)
 {
     PlatformBusDevice *pbus;
@@ -211,12 +196,8 @@ static void platform_bus_realize(DeviceState *dev, Error **errp)
         sysbus_init_irq(d, &pbus->irqs[i]);
     }
 
-    /*
-     * Register notifier that allows us to gather dangling devices once the
-     * machine is completely assembled
-     */
-    pbus->notifier.notify = platform_bus_init_notify;
-    qemu_add_machine_init_done_notifier(&pbus->notifier);
+    /* some devices might be initialized before so update used IRQs map */
+    plaform_bus_refresh_irqs(pbus);
 }
 
 static Property platform_bus_properties[] = {