RE: [PATCH V6 4/9] hw/acpi: Init GED framework with CPU hotplug events

[Salil Mehta]

Hi Alex,

> From: Alex Bennée <alex.bennee@linaro.org>
> Sent: Thursday, October 19, 2023 11:16 AM
> To: Salil Mehta <salil.mehta@huawei.com>
> Cc: qemu-devel@nongnu.org; qemu-arm@nongnu.org; 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;
> david@redhat.com; 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;
> linux@armlinux.org.uk; darren@os.amperecomputing.com;
> ilkka@os.amperecomputing.com; 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 V6 4/9] hw/acpi: Init GED framework with CPU hotplug
> events
> 
> 
> Salil Mehta <salil.mehta@huawei.com> writes:
> 
> > 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.
> 
> Should we also update the docs here:
> 
>   https://qemu.readthedocs.io/en/master/specs/acpi_hw_reduced_hotplug.html
> 
> (see docs/specs/acpi_hw_reduced_hotplug.rst)


Good point. Will do.


> to add the new bits? Or maybe an update to documentation as the last
> commit?

Will add one more patch at the last for this documentation change.

Thanks for identifying this.

Cheers
Salil.


> 
> >
> > 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>
> > Reviewed-by: David Hildenbrand <david@redhat.com>
> > Tested-by: Vishnu Pajjuri <vishnu@os.amperecomputing.com>
> > Tested-by: Xianglai Li <lixianglai@loongson.cn>
> > ---
> >  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 ba84ce0214..a803ea818e 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"
> > @@ -95,6 +96,7 @@ 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;
> > @@ -106,6 +108,9 @@ struct AcpiGedState {
> >      SysBusDevice parent_obj;
> >      MemHotplugState memhp_state;
> >      MemoryRegion container_memhp;
> > +    CPUHotplugState cpuhp_state;
> > +    MemoryRegion container_cpuhp;
> > +    AcpiCpuHotplug cpuhp;
> >      GEDState ged_state;
> >      uint32_t ged_event_bitmap;
> >      qemu_irq irq;
> 
> 
> --
> Alex Bennée
> Virtualisation Tech Lead @ Linaro