RE: [PATCH V3 04/10] hw/acpi: Init GED framework with cpu hotplug events

[Salil Mehta]

> From: David Hildenbrand <david@redhat.com>
> Sent: Monday, October 9, 2023 1:27 PM
> To: Salil Mehta <salil.mehta@huawei.com>; qemu-devel@nongnu.org; qemu-
> arm@nongnu.org
> Cc: maz@kernel.org; jean-philippe@linaro.org; Jonathan Cameron
> <jonathan.cameron@huawei.com>; lpieralisi@kernel.org;
> peter.maydell@linaro.org; richard.henderson@linaro.org;
> imammedo@redhat.com; andrew.jones@linux.dev; philmd@linaro.org;
> eric.auger@redhat.com; oliver.upton@linux.dev; pbonzini@redhat.com;
> mst@redhat.com; will@kernel.org; gshan@redhat.com; rafael@kernel.org;
> alex.bennee@linaro.org; linux@armlinux.org.uk;
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> vishnu@os.amperecomputing.com; karl.heubaum@oracle.com;
> miguel.luis@oracle.com; salil.mehta@opnsrc.net; zhukeqian
> <zhukeqian1@huawei.com>; wangxiongfeng (C) <wangxiongfeng2@huawei.com>;
> wangyanan (Y) <wangyanan55@huawei.com>; jiakernel2@gmail.com;
> maobibo@loongson.cn; lixianglai@loongson.cn; Linuxarm <linuxarm@huawei.com>
> Subject: Re: [PATCH V3 04/10] hw/acpi: Init GED framework with cpu hotplug
> events
> 
> On 09.10.23 13:28, Salil Mehta wrote:
> > ACPI GED(as described in the ACPI 6.2 spec) can be used to generate ACPI
> events
> > when OSPM/guest receives an interrupt listed in the _CRS object of GED.
> OSPM
> > then maps or demultiplexes the event by evaluating _EVT method.
> >
> > This change adds the support of cpu hotplug event initialization in the
> > existing GED framework.
> >
> > 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>
> > Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> > Reviewed-by: Gavin Shan <gshan@redhat.com>
> > ---
> >   hw/acpi/generic_event_device.c         | 8 ++++++++
> >   include/hw/acpi/generic_event_device.h | 5 +++++
> >   2 files changed, 13 insertions(+)
> >
> > diff --git a/hw/acpi/generic_event_device.c
> b/hw/acpi/generic_event_device.c
> > index a3d31631fe..d2fa1d0e4a 100644
> > --- a/hw/acpi/generic_event_device.c
> > +++ b/hw/acpi/generic_event_device.c
> > @@ -25,6 +25,7 @@ static const uint32_t ged_supported_events[] = {
> >       ACPI_GED_MEM_HOTPLUG_EVT,
> >       ACPI_GED_PWR_DOWN_EVT,
> >       ACPI_GED_NVDIMM_HOTPLUG_EVT,
> > +    ACPI_GED_CPU_HOTPLUG_EVT,
> >   };
> >
> >   /*
> > @@ -400,6 +401,13 @@ static void acpi_ged_initfn(Object *obj)
> >       memory_region_init_io(&ged_st->regs, obj, &ged_regs_ops, ged_st,
> >                             TYPE_ACPI_GED "-regs", ACPI_GED_REG_COUNT);
> >       sysbus_init_mmio(sbd, &ged_st->regs);
> > +
> > +    s->cpuhp.device = OBJECT(s);
> > +    memory_region_init(&s->container_cpuhp, OBJECT(dev), "cpuhp
> container",
> > +                       ACPI_CPU_HOTPLUG_REG_LEN);
> > +    sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->container_cpuhp);
> > +    cpu_hotplug_hw_init(&s->container_cpuhp, OBJECT(dev),
> > +                        &s->cpuhp_state, 0);
> >   }
> >
> >   static void acpi_ged_class_init(ObjectClass *class, void *data)
> > diff --git a/include/hw/acpi/generic_event_device.h
> b/include/hw/acpi/generic_event_device.h
> > index d831bbd889..d0a5a43abf 100644
> > --- a/include/hw/acpi/generic_event_device.h
> > +++ b/include/hw/acpi/generic_event_device.h
> > @@ -60,6 +60,7 @@
> >   #define HW_ACPI_GENERIC_EVENT_DEVICE_H
> >
> >   #include "hw/sysbus.h"
> > +#include "hw/acpi/cpu_hotplug.h"
> >   #include "hw/acpi/memory_hotplug.h"
> >   #include "hw/acpi/ghes.h"
> >   #include "qom/object.h"
> > @@ -97,6 +98,7 @@ OBJECT_DECLARE_SIMPLE_TYPE(AcpiGedState, ACPI_GED)
> >   #define ACPI_GED_MEM_HOTPLUG_EVT   0x1
> >   #define ACPI_GED_PWR_DOWN_EVT      0x2
> >   #define ACPI_GED_NVDIMM_HOTPLUG_EVT 0x4
> > +#define ACPI_GED_CPU_HOTPLUG_EVT    0x8
> >
> >   typedef struct GEDState {
> >       MemoryRegion evt;
> > @@ -108,6 +110,9 @@ struct AcpiGedState {
> >       SysBusDevice parent_obj;
> >       MemHotplugState memhp_state;
> >       MemoryRegion container_memhp;
> > +    CPUHotplugState cpuhp_state;
> > +    MemoryRegion container_cpuhp;
> > +    AcpiCpuHotplug cpuhp;
> 
> Am I wrong or is that member completely unused/uninitialized?

No it is not. Please check below change in acpi_ged_initfn()

+    s->cpuhp.device = OBJECT(s);


Thanks
Salil.