Re: [PATCH v2 5/7] hw/arm/virt: Add nvdimm hotplug support

[Igor Mammedov <imammedo@redhat.com>]

On Fri, 17 Jan 2020 17:45:20 +0000
Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> wrote:

> This adds support for nvdimm hotplug events through GED
> and enables nvdimm for the arm/virt. Now Guests with ACPI
> can have both cold and hot plug of nvdimms.
> 
> Hot removal functionality is not yet supported.
> 
> Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
> Reviewed-by: Igor Mammedov <imammedo@redhat.com>
> ---
>  docs/specs/acpi_hw_reduced_hotplug.rst |  1 +
>  hw/acpi/generic_event_device.c         | 13 +++++++++++++
>  hw/arm/virt.c                          | 16 +++++++++++-----
>  include/hw/acpi/generic_event_device.h |  1 +
>  4 files changed, 26 insertions(+), 5 deletions(-)
> 
> diff --git a/docs/specs/acpi_hw_reduced_hotplug.rst b/docs/specs/acpi_hw_reduced_hotplug.rst
> index 911a98255b..e3abe975bf 100644
> --- a/docs/specs/acpi_hw_reduced_hotplug.rst
> +++ b/docs/specs/acpi_hw_reduced_hotplug.rst
> @@ -63,6 +63,7 @@ GED IO interface (4 byte access)
>      bits:
>         0: Memory hotplug event
>         1: System power down event
> +       2: NVDIMM hotplug event
>      2-31: Reserved
>  
>  **write_access:**
> diff --git a/hw/acpi/generic_event_device.c b/hw/acpi/generic_event_device.c
> index 9cee90cc70..ad1b684304 100644
> --- a/hw/acpi/generic_event_device.c
> +++ b/hw/acpi/generic_event_device.c
> @@ -16,6 +16,7 @@
>  #include "hw/acpi/generic_event_device.h"
>  #include "hw/irq.h"
>  #include "hw/mem/pc-dimm.h"
> +#include "hw/mem/nvdimm.h"
>  #include "hw/qdev-properties.h"
>  #include "migration/vmstate.h"
>  #include "qemu/error-report.h"
> @@ -23,6 +24,7 @@
>  static const uint32_t ged_supported_events[] = {
>      ACPI_GED_MEM_HOTPLUG_EVT,
>      ACPI_GED_PWR_DOWN_EVT,
> +    ACPI_GED_NVDIMM_HOTPLUG_EVT,
>  };
>  
>  /*
> @@ -110,6 +112,11 @@ void build_ged_aml(Aml *table, const char *name, HotplugHandler *hotplug_dev,
>                             aml_notify(aml_name(ACPI_POWER_BUTTON_DEVICE),
>                                        aml_int(0x80)));
>                  break;
> +            case ACPI_GED_NVDIMM_HOTPLUG_EVT:
> +                aml_append(if_ctx,
> +                           aml_notify(aml_name("\\_SB.NVDR"),
> +                                      aml_int(0x80)));
> +                break;
>              default:
>                  /*
>                   * Please make sure all the events in ged_supported_events[]
> @@ -175,7 +182,11 @@ static void acpi_ged_device_plug_cb(HotplugHandler *hotplug_dev,
>      AcpiGedState *s = ACPI_GED(hotplug_dev);
>  
>      if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
> +        if (object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM)) {
> +            nvdimm_acpi_plug_cb(hotplug_dev, dev);
> +        } else {
>              acpi_memory_plug_cb(hotplug_dev, &s->memhp_state, dev, errp);
> +        }
>      } else {
>          error_setg(errp, "virt: device plug request for unsupported device"
>                     " type: %s", object_get_typename(OBJECT(dev)));
> @@ -192,6 +203,8 @@ static void acpi_ged_send_event(AcpiDeviceIf *adev, AcpiEventStatusBits ev)
>          sel = ACPI_GED_MEM_HOTPLUG_EVT;
>      } else if (ev & ACPI_POWER_DOWN_STATUS) {
>          sel = ACPI_GED_PWR_DOWN_EVT;
> +    } else if (ev & ACPI_NVDIMM_HOTPLUG_STATUS) {
> +        sel = ACPI_GED_NVDIMM_HOTPLUG_EVT;
>      } else {
>          /* Unknown event. Return without generating interrupt. */
>          warn_report("GED: Unsupported event %d. No irq injected", ev);
> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index 7987c8f5b8..5ea2584491 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -543,6 +543,10 @@ static inline DeviceState *create_acpi_ged(VirtMachineState *vms)
>          event |= ACPI_GED_MEM_HOTPLUG_EVT;
>      }
>  
> +    if (ms->nvdimms_state->is_enabled) {
> +        event |= ACPI_GED_NVDIMM_HOTPLUG_EVT;
> +    }
> +
>      dev = qdev_create(NULL, TYPE_ACPI_GED);
>      qdev_prop_set_uint32(dev, "ged-event", event);
>  
> @@ -1928,19 +1932,20 @@ static void virt_memory_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
>                                   Error **errp)
>  {
>      VirtMachineState *vms = VIRT_MACHINE(hotplug_dev);
> +    const MachineState *ms = MACHINE(hotplug_dev);
>      const bool is_nvdimm = object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM);
>  
> -    if (is_nvdimm) {
> -        error_setg(errp, "nvdimm is not yet supported");
> -        return;
> -    }
> -
>      if (!vms->acpi_dev) {
>          error_setg(errp,
>                     "memory hotplug is not enabled: missing acpi-ged device");
>          return;
>      }
>  
> +    if (is_nvdimm && !ms->nvdimms_state->is_enabled) {
> +        error_setg(errp, "nvdimm is not enabled: missing 'nvdimm' in '-M'");
s/missing 'nvdimm' in '-M'/add 'nvdimm=on' to '-M'/

> +        return;
> +    }
> +
>      pc_dimm_pre_plug(PC_DIMM(dev), MACHINE(hotplug_dev), NULL, errp);
>  }
>  
> @@ -2071,6 +2076,7 @@ static void virt_machine_class_init(ObjectClass *oc, void *data)
>      hc->plug = virt_machine_device_plug_cb;
>      hc->unplug_request = virt_machine_device_unplug_request_cb;
>      mc->numa_mem_supported = true;
> +    mc->nvdimm_supported = true;
>      mc->auto_enable_numa_with_memhp = true;
>  }
>  
> diff --git a/include/hw/acpi/generic_event_device.h b/include/hw/acpi/generic_event_device.h
> index d157eac088..9eb86ca4fd 100644
> --- a/include/hw/acpi/generic_event_device.h
> +++ b/include/hw/acpi/generic_event_device.h
> @@ -82,6 +82,7 @@
>   */
>  #define ACPI_GED_MEM_HOTPLUG_EVT   0x1
>  #define ACPI_GED_PWR_DOWN_EVT      0x2
> +#define ACPI_GED_NVDIMM_HOTPLUG_EVT 0x4
>  
>  typedef struct GEDState {
>      MemoryRegion io;