On Thu, Aug 8, 2024 at 2:18 PM Peter Maydell <peter.mayd...@linaro.org> wrote: > > On Tue, 6 Aug 2024 at 17:08, Juraj Marcin <jmar...@redhat.com> wrote: > > > > Some devices need to distinguish cold start reset from waking up from a > > suspended state. This patch adds new value to the enum, and updates the > > i386 wakeup method to use this new reset type. > > > > Signed-off-by: Juraj Marcin <jmar...@redhat.com> > > --- > > docs/devel/reset.rst | 7 +++++++ > > hw/i386/pc.c | 2 +- > > include/hw/resettable.h | 2 ++ > > 3 files changed, 10 insertions(+), 1 deletion(-) > > > > diff --git a/docs/devel/reset.rst b/docs/devel/reset.rst > > index 9746a4e8a0..30c9a0cc2b 100644 > > --- a/docs/devel/reset.rst > > +++ b/docs/devel/reset.rst > > @@ -44,6 +44,13 @@ The Resettable interface handles reset types with an > > enum ``ResetType``: > > value on each cold reset, such as RNG seed information, and which they > > must not reinitialize on a snapshot-load reset. > > > > +``RESET_TYPE_WAKEUP`` > > + This type is used when the machine is woken up from a suspended state > > (deep > > + sleep, suspend-to-ram). Devices that must not be reset to their initial > > state > > + after wake-up (for example virtio-mem) can use this state to > > differentiate > > + cold start from wake-up can use this state to differentiate cold start > > from > > + wake-up. > > I feel like this needs more clarity about what this is, since > as a reset type it's a general behaviour, not a machine > specific one. What exactly is "wakeup" and when does it happen? > How does it differ from what you might call a "warm" reset, > where the user pressed the front-panel reset button? > Why is virtio-mem in particular interesting here?
Thank you for the feedback! I have rewritten the paragraph: This type is called for a reset when the system is being woken up from a suspended state using the ``qemu_system_wakeup()`` function. If the machine type needs to reset in its ``MachineClass::wakeup()`` method, this reset type should be used so that devices can differentiate system wake-up from other reset types. For example, a virtio-mem device must not unplug its memory during wake-up, as that would clear the guest RAM. Is it clearer? Thank you! > > thanks > -- PMM > -- Juraj Marcin
