RE: [PATCH V2 06/10] hw/acpi: Update GED _EVT method AML with cpu scan

[Salil Mehta]

> From: Jonathan Cameron <jonathan.cameron@huawei.com>
> Sent: Monday, October 2, 2023 5:14 PM
> To: Salil Mehta <salil.mehta@huawei.com>
> Cc: qemu-devel@nongnu.org; qemu-arm@nongnu.org; maz@kernel.org; jean-
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> Subject: Re: [PATCH V2 06/10] hw/acpi: Update GED _EVT method AML with cpu
> scan
> 
> On Sat, 30 Sep 2023 01:19:29 +0100
> Salil Mehta <salil.mehta@huawei.com> wrote:
> 
> > OSPM evaluates _EVT method to map the event. The cpu hotplug event 
> > eventually
> > results in start of the cpu scan. Scan figures out the cpu and the kind of
> > event(plug/unplug) and notifies it back to the guest.
> >
> > The change in this patch updates the GED AML _EVT method with the call to
> > \\_SB.CPUS.CSCN which will do above.
> >
> > Co-developed-by: Keqian Zhu <zhukeqian1@huawei.com>
> > Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com>
> > Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
> One trivial suggested addition inline (dropping existing definition that this
> replicates). With that tidied up
> 
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Thanks
Salil.

> 
> > ---
> >  hw/acpi/generic_event_device.c | 4 ++++
> >  include/hw/acpi/cpu_hotplug.h  | 2 ++
> >  2 files changed, 6 insertions(+)
> >
> > diff --git a/hw/acpi/generic_event_device.c
> b/hw/acpi/generic_event_device.c
> > index d2fa1d0e4a..62d504d231 100644
> > --- a/hw/acpi/generic_event_device.c
> > +++ b/hw/acpi/generic_event_device.c
> > @@ -108,6 +108,10 @@ void build_ged_aml(Aml *table, const char *name,
> HotplugHandler *hotplug_dev,
> >                  aml_append(if_ctx, aml_call0(MEMORY_DEVICES_CONTAINER
> "."
> >                                               MEMORY_SLOT_SCAN_METHOD));
> >                  break;
> > +            case ACPI_GED_CPU_HOTPLUG_EVT:
> > +                aml_append(if_ctx, aml_call0(ACPI_CPU_CONTAINER "."
> > +                                             ACPI_CPU_SCAN_METHOD));
> > +                break;
> >              case ACPI_GED_PWR_DOWN_EVT:
> >                  aml_append(if_ctx,
> >
> aml_notify(aml_name(ACPI_POWER_BUTTON_DEVICE),
> > diff --git a/include/hw/acpi/cpu_hotplug.h
> b/include/hw/acpi/cpu_hotplug.h
> > index 48b291e45e..ef631750b4 100644
> > --- a/include/hw/acpi/cpu_hotplug.h
> > +++ b/include/hw/acpi/cpu_hotplug.h
> > @@ -20,6 +20,8 @@
> >  #include "hw/acpi/cpu.h"
> >
> >  #define ACPI_CPU_HOTPLUG_REG_LEN 12
> > +#define ACPI_CPU_SCAN_METHOD "CSCN"
> 
> This seems to already be defined in hw/acpi/cpu.c
> Can we drop it from there given that file now includes this
> header anyway.

Perhaps I can assign this to the macro in the hw/acpi/cpu.c?

Thanks
Salil.