Add a function resettable_change_parent() to do the required
plumbing when changing the parent a of Resettable object.
We need to make sure that the reset state of the object remains
coherent with the reset state of the new parent.
We make the 2 following hypothesis:
+ when an object is put in a parent under reset, the object goes in
reset.
+ when an object is removed from a parent under reset, the object
leaves reset.
The added function avoids any glitch if both old and new parent are
already in reset.
Signed-off-by: Damien Hedde <damien.hedde@greensocs.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20200123132823.1117486-6-damien.hedde@greensocs.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit defines an interface allowing multi-phase reset. This aims
to solve a problem of the actual single-phase reset (built in
DeviceClass and BusClass): reset behavior is dependent on the order
in which reset handlers are called. In particular doing external
side-effect (like setting an qemu_irq) is problematic because receiving
object may not be reset yet.
The Resettable interface divides the reset in 3 well defined phases.
To reset an object tree, all 1st phases are executed then all 2nd then
all 3rd. See the comments in include/hw/resettable.h for a more complete
description. The interface defines 3 phases to let the future
possibility of holding an object into reset for some time.
The qdev/qbus reset in DeviceClass and BusClass will be modified in
following commits to use this interface. A mechanism is provided
to allow executing a transitional reset handler in place of the 2nd
phase which is executed in children-then-parent order inside a tree.
This will allow to transition devices and buses smoothly while
keeping the exact current qdev/qbus reset behavior for now.
Documentation will be added in a following commit.
Signed-off-by: Damien Hedde <damien.hedde@greensocs.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20200123132823.1117486-4-damien.hedde@greensocs.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Adds trace events to reset procedure and when updating the parent
bus of a device.
Signed-off-by: Damien Hedde <damien.hedde@greensocs.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20200123132823.1117486-3-damien.hedde@greensocs.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This adds a trace point which prints every loaded image. This includes
bios/firmware/kernel/initradmdisk/pcirom.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190613050937.124903-1-aik@ozlabs.ru>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
