Re: [Qemu-devel] [PATCH v4 3/3] pc: memhp: enable nvdimm device hotplug

[Igor Mammedov <imammedo@redhat.com>]

On Thu,  3 Nov 2016 11:51:30 +0800
Xiao Guangrong <guangrong.xiao@linux.intel.com> wrote:

> _GPE.E04 is dedicated for nvdimm device hotplug
> 
> Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
> ---
>  default-configs/mips-softmmu-common.mak |  1 +
>  docs/specs/acpi_nvdimm.txt              |  5 +++++
>  hw/acpi/ich9.c                          |  8 ++++++--
>  hw/acpi/nvdimm.c                        |  7 +++++++
>  hw/acpi/piix4.c                         |  7 ++++++-
>  hw/i386/acpi-build.c                    |  7 +++++++
>  hw/i386/pc.c                            | 12 ++++++++++++
>  hw/mem/nvdimm.c                         |  4 ----
>  include/hw/acpi/acpi_dev_interface.h    |  1 +
>  include/hw/mem/nvdimm.h                 |  1 +
>  10 files changed, 46 insertions(+), 7 deletions(-)
> 
> diff --git a/default-configs/mips-softmmu-common.mak b/default-configs/mips-softmmu-common.mak
> index 0394514..f0676f5 100644
> --- a/default-configs/mips-softmmu-common.mak
> +++ b/default-configs/mips-softmmu-common.mak
> @@ -17,6 +17,7 @@ CONFIG_FDC=y
>  CONFIG_ACPI=y
>  CONFIG_ACPI_X86=y
>  CONFIG_ACPI_MEMORY_HOTPLUG=y
> +CONFIG_ACPI_NVDIMM=y
>  CONFIG_ACPI_CPU_HOTPLUG=y
>  CONFIG_APM=y
>  CONFIG_I8257=y
> diff --git a/docs/specs/acpi_nvdimm.txt b/docs/specs/acpi_nvdimm.txt
> index 364e832..7887e57 100644
> --- a/docs/specs/acpi_nvdimm.txt
> +++ b/docs/specs/acpi_nvdimm.txt
> @@ -137,6 +137,11 @@ _DSM process diagram:
>   | result from the page     |      |              |
>   +--------------------------+      +--------------+
>  
> +NVDIMM hotplug
> +--------------
> +ACPI BIOS GPE.4 handler is dedicated for notifying OS about nvdimm device
> +hot-add and hot-remove events.
s/and hot-remove //


>  QEMU internal use only _DSM function
>  ------------------------------------
>  There is the function introduced by QEMU and only used by QEMU internal.
> diff --git a/hw/acpi/ich9.c b/hw/acpi/ich9.c
> index e5a3c18..830c475 100644
> --- a/hw/acpi/ich9.c
> +++ b/hw/acpi/ich9.c
> @@ -490,8 +490,12 @@ void ich9_pm_device_plug_cb(HotplugHandler *hotplug_dev, DeviceState *dev,
>  
>      if (lpc->pm.acpi_memory_hotplug.is_enabled &&
>          object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
> -        acpi_memory_plug_cb(hotplug_dev, &lpc->pm.acpi_memory_hotplug,
> -                            dev, errp);
> +        if (object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM)) {
> +            nvdimm_acpi_plug_cb(hotplug_dev, dev);
> +        } else {
> +            acpi_memory_plug_cb(hotplug_dev, &lpc->pm.acpi_memory_hotplug,
> +                                dev, errp);
> +        }
>      } else if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
>          if (lpc->pm.cpu_hotplug_legacy) {
>              legacy_acpi_cpu_plug_cb(hotplug_dev, &lpc->pm.gpe_cpu, dev, errp);
> diff --git a/hw/acpi/nvdimm.c b/hw/acpi/nvdimm.c
> index 593ac0d..b8548cc 100644
> --- a/hw/acpi/nvdimm.c
> +++ b/hw/acpi/nvdimm.c
> @@ -874,6 +874,13 @@ static const MemoryRegionOps nvdimm_dsm_ops = {
>      },
>  };
>  
> +void nvdimm_acpi_plug_cb(HotplugHandler *hotplug_dev, DeviceState *dev)
> +{
> +    if (dev->hotplugged) {
> +        acpi_send_event(DEVICE(hotplug_dev), ACPI_NVDIMM_HOTPLUG_STATUS);
> +    }
> +}
> +
>  void nvdimm_init_acpi_state(AcpiNVDIMMState *state, MemoryRegion *io,
>                              FWCfgState *fw_cfg, Object *owner)
>  {
> diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c
> index 2adc246..17d36bd 100644
> --- a/hw/acpi/piix4.c
> +++ b/hw/acpi/piix4.c
> @@ -378,7 +378,12 @@ static void piix4_device_plug_cb(HotplugHandler *hotplug_dev,
>  
>      if (s->acpi_memory_hotplug.is_enabled &&
>          object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
> -        acpi_memory_plug_cb(hotplug_dev, &s->acpi_memory_hotplug, dev, errp);
> +        if (object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM)) {
> +            nvdimm_acpi_plug_cb(hotplug_dev, dev);
> +        } else {
> +            acpi_memory_plug_cb(hotplug_dev, &s->acpi_memory_hotplug,
> +                                dev, errp);
> +        }
>      } else if (object_dynamic_cast(OBJECT(dev), TYPE_PCI_DEVICE)) {
>          acpi_pcihp_device_plug_cb(hotplug_dev, &s->acpi_pci_hotplug, dev, errp);
>      } else if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> index bc49958..32270c3 100644
> --- a/hw/i386/acpi-build.c
> +++ b/hw/i386/acpi-build.c
> @@ -2039,6 +2039,13 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>          method = aml_method("_E03", 0, AML_NOTSERIALIZED);
>          aml_append(method, aml_call0(MEMORY_HOTPLUG_HANDLER_PATH));
>          aml_append(scope, method);
> +
> +        if (pcms->acpi_nvdimm_state.is_enabled) {
> +            method = aml_method("_E04", 0, AML_NOTSERIALIZED);
> +            aml_append(method, aml_notify(aml_name("\\_SB.NVDR"),
> +                                          aml_int(0x80)));
> +            aml_append(scope, method);
> +        }
>      }
>      aml_append(dsdt, scope);
>  
> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> index 77ca7f4..0403452 100644
> --- a/hw/i386/pc.c
> +++ b/hw/i386/pc.c
> @@ -1723,6 +1723,12 @@ static void pc_dimm_unplug_request(HotplugHandler *hotplug_dev,
>          goto out;
>      }
>  
> +    if (object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM)) {
> +        error_setg(&local_err,
> +                   "nvdimm device hot unplug is not supported yet.");
> +        goto out;
> +    }
> +
>      hhc = HOTPLUG_HANDLER_GET_CLASS(pcms->acpi_dev);
>      hhc->unplug_request(HOTPLUG_HANDLER(pcms->acpi_dev), dev, &local_err);
>  
> @@ -1740,6 +1746,12 @@ static void pc_dimm_unplug(HotplugHandler *hotplug_dev,
>      HotplugHandlerClass *hhc;
>      Error *local_err = NULL;
>  
> +    if (object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM)) {
> +        error_setg(&local_err,
> +                   "nvdimm device hot unplug is not supported yet.");
> +        goto out;
> +    }
drop this as it's not reachable without unplug support for
NVDIMM in piix4/ich9, call chain for it would be:

  guest(MMIO on unplug)
      -> piix4/ich9 IO port handler
          ->hotplug_handler_unplug(hotplug_ctrl, dev, &local_err);
              -> pc_machine_device_unplug_cb
                  -> pc_dimm_unplug

>      hhc = HOTPLUG_HANDLER_GET_CLASS(pcms->acpi_dev);
>      hhc->unplug(HOTPLUG_HANDLER(pcms->acpi_dev), dev, &local_err);
>  
> diff --git a/hw/mem/nvdimm.c b/hw/mem/nvdimm.c
> index 7895805..db896b0 100644
> --- a/hw/mem/nvdimm.c
> +++ b/hw/mem/nvdimm.c
> @@ -148,13 +148,9 @@ static MemoryRegion *nvdimm_get_vmstate_memory_region(PCDIMMDevice *dimm)
>  
>  static void nvdimm_class_init(ObjectClass *oc, void *data)
>  {
> -    DeviceClass *dc = DEVICE_CLASS(oc);
>      PCDIMMDeviceClass *ddc = PC_DIMM_CLASS(oc);
>      NVDIMMClass *nvc = NVDIMM_CLASS(oc);
>  
> -    /* nvdimm hotplug has not been supported yet. */
> -    dc->hotpluggable = false;
> -
>      ddc->realize = nvdimm_realize;
>      ddc->get_memory_region = nvdimm_get_memory_region;
>      ddc->get_vmstate_memory_region = nvdimm_get_vmstate_memory_region;
> diff --git a/include/hw/acpi/acpi_dev_interface.h b/include/hw/acpi/acpi_dev_interface.h
> index da4ef7f..901a4ae 100644
> --- a/include/hw/acpi/acpi_dev_interface.h
> +++ b/include/hw/acpi/acpi_dev_interface.h
> @@ -10,6 +10,7 @@ typedef enum {
>      ACPI_PCI_HOTPLUG_STATUS = 2,
>      ACPI_CPU_HOTPLUG_STATUS = 4,
>      ACPI_MEMORY_HOTPLUG_STATUS = 8,
> +    ACPI_NVDIMM_HOTPLUG_STATUS = 16,
>  } AcpiEventStatusBits;
>  
>  #define TYPE_ACPI_DEVICE_IF "acpi-device-interface"
> diff --git a/include/hw/mem/nvdimm.h b/include/hw/mem/nvdimm.h
> index 232437c..4b90584 100644
> --- a/include/hw/mem/nvdimm.h
> +++ b/include/hw/mem/nvdimm.h
> @@ -133,4 +133,5 @@ void nvdimm_build_acpi(GArray *table_offsets, GArray *table_data,
>                         BIOSLinker *linker, AcpiNVDIMMState *state,
>                         uint32_t ram_slots);
>  void nvdimm_acpi_hotplug(AcpiNVDIMMState *state);
> +void nvdimm_acpi_plug_cb(HotplugHandler *hotplug_dev, DeviceState *dev);
>  #endif