[v4,05/14] tpm_crb: move ACPI table building to device interface

This logic is similar to TPM TIS ISA device. Since TPM CRB can only
support TPM 2.0 backends, we check for this in realize.

Signed-off-by: Joelle van Dyne <j@getutm.app>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
---
 hw/tpm/tpm_crb.h        |  2 ++
 hw/i386/acpi-build.c    | 23 -----------------------
 hw/tpm/tpm_crb.c        | 16 ++++++++++++++++
 hw/tpm/tpm_crb_common.c | 19 +++++++++++++++++++
 4 files changed, 37 insertions(+), 23 deletions(-)

On 10/31/23 00:00, Joelle van Dyne wrote:
> This logic is similar to TPM TIS ISA device. Since TPM CRB can only
> support TPM 2.0 backends, we check for this in realize.

The problem on x86_64 is that the creation of the ACPI doesn't seem to 
get invoked. The device then ends up not working under Linux. The 
problem seems to be

.parent = TYPE_DEVICE

When I change this to TYPE_ISA_DEVICE it starts generating the ACPI 
table. I am not sure what other side effects this may have, though.

    Stefan
> 
> Signed-off-by: Joelle van Dyne <j@getutm.app>
> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
> ---
>   hw/tpm/tpm_crb.h        |  2 ++
>   hw/i386/acpi-build.c    | 23 -----------------------
>   hw/tpm/tpm_crb.c        | 16 ++++++++++++++++
>   hw/tpm/tpm_crb_common.c | 19 +++++++++++++++++++
>   4 files changed, 37 insertions(+), 23 deletions(-)
> 
> diff --git a/hw/tpm/tpm_crb.h b/hw/tpm/tpm_crb.h
> index 36863e1664..e6a86e3fd1 100644
> --- a/hw/tpm/tpm_crb.h
> +++ b/hw/tpm/tpm_crb.h
> @@ -73,5 +73,7 @@ void tpm_crb_init_memory(Object *obj, TPMCRBState *s, Error **errp);
>   void tpm_crb_mem_save(TPMCRBState *s, uint32_t *saved_regs, void *saved_cmdmem);
>   void tpm_crb_mem_load(TPMCRBState *s, const uint32_t *saved_regs,
>                         const void *saved_cmdmem);
> +void tpm_crb_build_aml(TPMIf *ti, Aml *scope, uint32_t baseaddr, uint32_t size,
> +                       bool build_ppi);
>   
>   #endif /* TPM_TPM_CRB_H */
> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> index 80db183b78..ce3f7b2d91 100644
> --- a/hw/i386/acpi-build.c
> +++ b/hw/i386/acpi-build.c
> @@ -1441,9 +1441,6 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>       uint32_t nr_mem = machine->ram_slots;
>       int root_bus_limit = 0xFF;
>       PCIBus *bus = NULL;
> -#ifdef CONFIG_TPM
> -    TPMIf *tpm = tpm_find();
> -#endif
>       bool cxl_present = false;
>       int i;
>       VMBusBridge *vmbus_bridge = vmbus_bridge_find();
> @@ -1790,26 +1787,6 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>           }
>       }
>   
> -#ifdef CONFIG_TPM
> -    if (TPM_IS_CRB(tpm)) {
> -        dev = aml_device("TPM");
> -        aml_append(dev, aml_name_decl("_HID", aml_string("MSFT0101")));
> -        aml_append(dev, aml_name_decl("_STR",
> -                                      aml_string("TPM 2.0 Device")));
> -        crs = aml_resource_template();
> -        aml_append(crs, aml_memory32_fixed(TPM_CRB_ADDR_BASE,
> -                                           TPM_CRB_ADDR_SIZE, AML_READ_WRITE));
> -        aml_append(dev, aml_name_decl("_CRS", crs));
> -
> -        aml_append(dev, aml_name_decl("_STA", aml_int(0xf)));
> -        aml_append(dev, aml_name_decl("_UID", aml_int(1)));
> -
> -        tpm_build_ppi_acpi(tpm, dev);
> -
> -        aml_append(sb_scope, dev);
> -    }
> -#endif
> -
>       if (pcms->sgx_epc.size != 0) {
>           uint64_t epc_base = pcms->sgx_epc.base;
>           uint64_t epc_size = pcms->sgx_epc.size;
> diff --git a/hw/tpm/tpm_crb.c b/hw/tpm/tpm_crb.c
> index 99c64dd72a..8d57295b15 100644
> --- a/hw/tpm/tpm_crb.c
> +++ b/hw/tpm/tpm_crb.c
> @@ -19,6 +19,8 @@
>   #include "qemu/module.h"
>   #include "qapi/error.h"
>   #include "exec/address-spaces.h"
> +#include "hw/acpi/acpi_aml_interface.h"
> +#include "hw/acpi/tpm.h"
>   #include "hw/qdev-properties.h"
>   #include "hw/pci/pci_ids.h"
>   #include "hw/acpi/tpm.h"
> @@ -121,6 +123,11 @@ static void tpm_crb_none_realize(DeviceState *dev, Error **errp)
>           return;
>       }
>   
> +    if (tpm_crb_none_get_version(TPM_IF(s)) != TPM_VERSION_2_0) {
> +        error_setg(errp, "TPM CRB only supports TPM 2.0 backends");
> +        return;
> +    }
> +
>       tpm_crb_init_memory(OBJECT(s), &s->state, errp);
>   
>       /* only used for migration */
> @@ -142,10 +149,17 @@ static void tpm_crb_none_realize(DeviceState *dev, Error **errp)
>       }
>   }
>   
> +static void build_tpm_crb_none_aml(AcpiDevAmlIf *adev, Aml *scope)
> +{
> +    tpm_crb_build_aml(TPM_IF(adev), scope, TPM_CRB_ADDR_BASE, TPM_CRB_ADDR_SIZE,
> +                      true);
> +}
> +
>   static void tpm_crb_none_class_init(ObjectClass *klass, void *data)
>   {
>       DeviceClass *dc = DEVICE_CLASS(klass);
>       TPMIfClass *tc = TPM_IF_CLASS(klass);
> +    AcpiDevAmlIfClass *adevc = ACPI_DEV_AML_IF_CLASS(klass);
>   
>       dc->realize = tpm_crb_none_realize;
>       device_class_set_props(dc, tpm_crb_none_properties);
> @@ -154,6 +168,7 @@ static void tpm_crb_none_class_init(ObjectClass *klass, void *data)
>       tc->model = TPM_MODEL_TPM_CRB;
>       tc->get_version = tpm_crb_none_get_version;
>       tc->request_completed = tpm_crb_none_request_completed;
> +    adevc->build_dev_aml = build_tpm_crb_none_aml;
>   
>       set_bit(DEVICE_CATEGORY_MISC, dc->categories);
>   }
> @@ -166,6 +181,7 @@ static const TypeInfo tpm_crb_none_info = {
>       .class_init  = tpm_crb_none_class_init,
>       .interfaces = (InterfaceInfo[]) {
>           { TYPE_TPM_IF },
> +        { TYPE_ACPI_DEV_AML_IF },
>           { }
>       }
>   };
> diff --git a/hw/tpm/tpm_crb_common.c b/hw/tpm/tpm_crb_common.c
> index 605e8576e9..4fff0c6b59 100644
> --- a/hw/tpm/tpm_crb_common.c
> +++ b/hw/tpm/tpm_crb_common.c
> @@ -239,3 +239,22 @@ void tpm_crb_mem_load(TPMCRBState *s, const uint32_t *saved_regs,
>       memcpy(regs, saved_regs, TPM_CRB_R_MAX);
>       memcpy(&regs[R_CRB_DATA_BUFFER], saved_cmdmem, A_CRB_DATA_BUFFER);
>   }
> +
> +void tpm_crb_build_aml(TPMIf *ti, Aml *scope, uint32_t baseaddr, uint32_t size,
> +                       bool build_ppi)
> +{
> +    Aml *dev, *crs;
> +
> +    dev = aml_device("TPM");
> +    aml_append(dev, aml_name_decl("_HID", aml_string("MSFT0101")));
> +    aml_append(dev, aml_name_decl("_STR", aml_string("TPM 2.0 Device")));
> +    aml_append(dev, aml_name_decl("_UID", aml_int(1)));
> +    aml_append(dev, aml_name_decl("_STA", aml_int(0xF)));
> +    crs = aml_resource_template();
> +    aml_append(crs, aml_memory32_fixed(baseaddr, size, AML_READ_WRITE));
> +    aml_append(dev, aml_name_decl("_CRS", crs));
> +    if (build_ppi) {
> +        tpm_build_ppi_acpi(ti, dev);
> +    }
> +    aml_append(scope, dev);
> +}

On Thu, Nov 2, 2023 at 11:50 AM Stefan Berger <stefanb@linux.ibm.com> wrote:
>
>
>
> On 10/31/23 00:00, Joelle van Dyne wrote:
> > This logic is similar to TPM TIS ISA device. Since TPM CRB can only
> > support TPM 2.0 backends, we check for this in realize.
>
> The problem on x86_64 is that the creation of the ACPI doesn't seem to
> get invoked. The device then ends up not working under Linux. The
> problem seems to be
>
> .parent = TYPE_DEVICE
>
> When I change this to TYPE_ISA_DEVICE it starts generating the ACPI
> table. I am not sure what other side effects this may have, though.
Ah sorry, this is probably a side effect of the patch I dropped where
the bus was moved back from ISA to SysBus. The patch was dropped
because people complained that the side effects of a new device
appearing on the ISA bus during migration is unknown. That means we
will probably have to add some logic to call the ACPI build methods on
non-ISA devices.

>
>     Stefan
> >
> > Signed-off-by: Joelle van Dyne <j@getutm.app>
> > Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
> > ---
> >   hw/tpm/tpm_crb.h        |  2 ++
> >   hw/i386/acpi-build.c    | 23 -----------------------
> >   hw/tpm/tpm_crb.c        | 16 ++++++++++++++++
> >   hw/tpm/tpm_crb_common.c | 19 +++++++++++++++++++
> >   4 files changed, 37 insertions(+), 23 deletions(-)
> >
> > diff --git a/hw/tpm/tpm_crb.h b/hw/tpm/tpm_crb.h
> > index 36863e1664..e6a86e3fd1 100644
> > --- a/hw/tpm/tpm_crb.h
> > +++ b/hw/tpm/tpm_crb.h
> > @@ -73,5 +73,7 @@ void tpm_crb_init_memory(Object *obj, TPMCRBState *s, Error **errp);
> >   void tpm_crb_mem_save(TPMCRBState *s, uint32_t *saved_regs, void *saved_cmdmem);
> >   void tpm_crb_mem_load(TPMCRBState *s, const uint32_t *saved_regs,
> >                         const void *saved_cmdmem);
> > +void tpm_crb_build_aml(TPMIf *ti, Aml *scope, uint32_t baseaddr, uint32_t size,
> > +                       bool build_ppi);
> >
> >   #endif /* TPM_TPM_CRB_H */
> > diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> > index 80db183b78..ce3f7b2d91 100644
> > --- a/hw/i386/acpi-build.c
> > +++ b/hw/i386/acpi-build.c
> > @@ -1441,9 +1441,6 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
> >       uint32_t nr_mem = machine->ram_slots;
> >       int root_bus_limit = 0xFF;
> >       PCIBus *bus = NULL;
> > -#ifdef CONFIG_TPM
> > -    TPMIf *tpm = tpm_find();
> > -#endif
> >       bool cxl_present = false;
> >       int i;
> >       VMBusBridge *vmbus_bridge = vmbus_bridge_find();
> > @@ -1790,26 +1787,6 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
> >           }
> >       }
> >
> > -#ifdef CONFIG_TPM
> > -    if (TPM_IS_CRB(tpm)) {
> > -        dev = aml_device("TPM");
> > -        aml_append(dev, aml_name_decl("_HID", aml_string("MSFT0101")));
> > -        aml_append(dev, aml_name_decl("_STR",
> > -                                      aml_string("TPM 2.0 Device")));
> > -        crs = aml_resource_template();
> > -        aml_append(crs, aml_memory32_fixed(TPM_CRB_ADDR_BASE,
> > -                                           TPM_CRB_ADDR_SIZE, AML_READ_WRITE));
> > -        aml_append(dev, aml_name_decl("_CRS", crs));
> > -
> > -        aml_append(dev, aml_name_decl("_STA", aml_int(0xf)));
> > -        aml_append(dev, aml_name_decl("_UID", aml_int(1)));
> > -
> > -        tpm_build_ppi_acpi(tpm, dev);
> > -
> > -        aml_append(sb_scope, dev);
> > -    }
> > -#endif
> > -
> >       if (pcms->sgx_epc.size != 0) {
> >           uint64_t epc_base = pcms->sgx_epc.base;
> >           uint64_t epc_size = pcms->sgx_epc.size;
> > diff --git a/hw/tpm/tpm_crb.c b/hw/tpm/tpm_crb.c
> > index 99c64dd72a..8d57295b15 100644
> > --- a/hw/tpm/tpm_crb.c
> > +++ b/hw/tpm/tpm_crb.c
> > @@ -19,6 +19,8 @@
> >   #include "qemu/module.h"
> >   #include "qapi/error.h"
> >   #include "exec/address-spaces.h"
> > +#include "hw/acpi/acpi_aml_interface.h"
> > +#include "hw/acpi/tpm.h"
> >   #include "hw/qdev-properties.h"
> >   #include "hw/pci/pci_ids.h"
> >   #include "hw/acpi/tpm.h"
> > @@ -121,6 +123,11 @@ static void tpm_crb_none_realize(DeviceState *dev, Error **errp)
> >           return;
> >       }
> >
> > +    if (tpm_crb_none_get_version(TPM_IF(s)) != TPM_VERSION_2_0) {
> > +        error_setg(errp, "TPM CRB only supports TPM 2.0 backends");
> > +        return;
> > +    }
> > +
> >       tpm_crb_init_memory(OBJECT(s), &s->state, errp);
> >
> >       /* only used for migration */
> > @@ -142,10 +149,17 @@ static void tpm_crb_none_realize(DeviceState *dev, Error **errp)
> >       }
> >   }
> >
> > +static void build_tpm_crb_none_aml(AcpiDevAmlIf *adev, Aml *scope)
> > +{
> > +    tpm_crb_build_aml(TPM_IF(adev), scope, TPM_CRB_ADDR_BASE, TPM_CRB_ADDR_SIZE,
> > +                      true);
> > +}
> > +
> >   static void tpm_crb_none_class_init(ObjectClass *klass, void *data)
> >   {
> >       DeviceClass *dc = DEVICE_CLASS(klass);
> >       TPMIfClass *tc = TPM_IF_CLASS(klass);
> > +    AcpiDevAmlIfClass *adevc = ACPI_DEV_AML_IF_CLASS(klass);
> >
> >       dc->realize = tpm_crb_none_realize;
> >       device_class_set_props(dc, tpm_crb_none_properties);
> > @@ -154,6 +168,7 @@ static void tpm_crb_none_class_init(ObjectClass *klass, void *data)
> >       tc->model = TPM_MODEL_TPM_CRB;
> >       tc->get_version = tpm_crb_none_get_version;
> >       tc->request_completed = tpm_crb_none_request_completed;
> > +    adevc->build_dev_aml = build_tpm_crb_none_aml;
> >
> >       set_bit(DEVICE_CATEGORY_MISC, dc->categories);
> >   }
> > @@ -166,6 +181,7 @@ static const TypeInfo tpm_crb_none_info = {
> >       .class_init  = tpm_crb_none_class_init,
> >       .interfaces = (InterfaceInfo[]) {
> >           { TYPE_TPM_IF },
> > +        { TYPE_ACPI_DEV_AML_IF },
> >           { }
> >       }
> >   };
> > diff --git a/hw/tpm/tpm_crb_common.c b/hw/tpm/tpm_crb_common.c
> > index 605e8576e9..4fff0c6b59 100644
> > --- a/hw/tpm/tpm_crb_common.c
> > +++ b/hw/tpm/tpm_crb_common.c
> > @@ -239,3 +239,22 @@ void tpm_crb_mem_load(TPMCRBState *s, const uint32_t *saved_regs,
> >       memcpy(regs, saved_regs, TPM_CRB_R_MAX);
> >       memcpy(&regs[R_CRB_DATA_BUFFER], saved_cmdmem, A_CRB_DATA_BUFFER);
> >   }
> > +
> > +void tpm_crb_build_aml(TPMIf *ti, Aml *scope, uint32_t baseaddr, uint32_t size,
> > +                       bool build_ppi)
> > +{
> > +    Aml *dev, *crs;
> > +
> > +    dev = aml_device("TPM");
> > +    aml_append(dev, aml_name_decl("_HID", aml_string("MSFT0101")));
> > +    aml_append(dev, aml_name_decl("_STR", aml_string("TPM 2.0 Device")));
> > +    aml_append(dev, aml_name_decl("_UID", aml_int(1)));
> > +    aml_append(dev, aml_name_decl("_STA", aml_int(0xF)));
> > +    crs = aml_resource_template();
> > +    aml_append(crs, aml_memory32_fixed(baseaddr, size, AML_READ_WRITE));
> > +    aml_append(dev, aml_name_decl("_CRS", crs));
> > +    if (build_ppi) {
> > +        tpm_build_ppi_acpi(ti, dev);
> > +    }
> > +    aml_append(scope, dev);
> > +}

On 11/2/23 22:37, Joelle van Dyne wrote:
> On Thu, Nov 2, 2023 at 11:50 AM Stefan Berger <stefanb@linux.ibm.com> wrote:
>>
>>
>>
>> On 10/31/23 00:00, Joelle van Dyne wrote:
>>> This logic is similar to TPM TIS ISA device. Since TPM CRB can only
>>> support TPM 2.0 backends, we check for this in realize.
>>
>> The problem on x86_64 is that the creation of the ACPI doesn't seem to
>> get invoked. The device then ends up not working under Linux. The
>> problem seems to be
>>
>> .parent = TYPE_DEVICE
>>
>> When I change this to TYPE_ISA_DEVICE it starts generating the ACPI
>> table. I am not sure what other side effects this may have, though.
> Ah sorry, this is probably a side effect of the patch I dropped where
> the bus was moved back from ISA to SysBus. The patch was dropped
> because people complained that the side effects of a new device
> appearing on the ISA bus during migration is unknown. That means we
> will probably have to add some logic to call the ACPI build methods on
> non-ISA devices.

If you moved tpm_crb_build_aml() into a common file like tpm_acpi.c as 
tpm_build_aml() it could be called from multiple drivers. For the x86_64 
driver I would just call this function from its old location then.


     Stefan

> 
>>
>>      Stefan
>>>
>>> Signed-off-by: Joelle van Dyne <j@getutm.app>
>>> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
>>> ---
>>>    hw/tpm/tpm_crb.h        |  2 ++
>>>    hw/i386/acpi-build.c    | 23 -----------------------
>>>    hw/tpm/tpm_crb.c        | 16 ++++++++++++++++
>>>    hw/tpm/tpm_crb_common.c | 19 +++++++++++++++++++
>>>    4 files changed, 37 insertions(+), 23 deletions(-)
>>>
>>> diff --git a/hw/tpm/tpm_crb.h b/hw/tpm/tpm_crb.h
>>> index 36863e1664..e6a86e3fd1 100644
>>> --- a/hw/tpm/tpm_crb.h
>>> +++ b/hw/tpm/tpm_crb.h
>>> @@ -73,5 +73,7 @@ void tpm_crb_init_memory(Object *obj, TPMCRBState *s, Error **errp);
>>>    void tpm_crb_mem_save(TPMCRBState *s, uint32_t *saved_regs, void *saved_cmdmem);
>>>    void tpm_crb_mem_load(TPMCRBState *s, const uint32_t *saved_regs,
>>>                          const void *saved_cmdmem);
>>> +void tpm_crb_build_aml(TPMIf *ti, Aml *scope, uint32_t baseaddr, uint32_t size,
>>> +                       bool build_ppi);
>>>
>>>    #endif /* TPM_TPM_CRB_H */
>>> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
>>> index 80db183b78..ce3f7b2d91 100644
>>> --- a/hw/i386/acpi-build.c
>>> +++ b/hw/i386/acpi-build.c
>>> @@ -1441,9 +1441,6 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>>>        uint32_t nr_mem = machine->ram_slots;
>>>        int root_bus_limit = 0xFF;
>>>        PCIBus *bus = NULL;
>>> -#ifdef CONFIG_TPM
>>> -    TPMIf *tpm = tpm_find();
>>> -#endif
>>>        bool cxl_present = false;
>>>        int i;
>>>        VMBusBridge *vmbus_bridge = vmbus_bridge_find();
>>> @@ -1790,26 +1787,6 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
>>>            }
>>>        }
>>>
>>> -#ifdef CONFIG_TPM
>>> -    if (TPM_IS_CRB(tpm)) {
>>> -        dev = aml_device("TPM");
>>> -        aml_append(dev, aml_name_decl("_HID", aml_string("MSFT0101")));
>>> -        aml_append(dev, aml_name_decl("_STR",
>>> -                                      aml_string("TPM 2.0 Device")));
>>> -        crs = aml_resource_template();
>>> -        aml_append(crs, aml_memory32_fixed(TPM_CRB_ADDR_BASE,
>>> -                                           TPM_CRB_ADDR_SIZE, AML_READ_WRITE));
>>> -        aml_append(dev, aml_name_decl("_CRS", crs));
>>> -
>>> -        aml_append(dev, aml_name_decl("_STA", aml_int(0xf)));
>>> -        aml_append(dev, aml_name_decl("_UID", aml_int(1)));
>>> -
>>> -        tpm_build_ppi_acpi(tpm, dev);
>>> -
>>> -        aml_append(sb_scope, dev);
>>> -    }
>>> -#endif
>>> -
>>>        if (pcms->sgx_epc.size != 0) {
>>>            uint64_t epc_base = pcms->sgx_epc.base;
>>>            uint64_t epc_size = pcms->sgx_epc.size;
>>> diff --git a/hw/tpm/tpm_crb.c b/hw/tpm/tpm_crb.c
>>> index 99c64dd72a..8d57295b15 100644
>>> --- a/hw/tpm/tpm_crb.c
>>> +++ b/hw/tpm/tpm_crb.c
>>> @@ -19,6 +19,8 @@
>>>    #include "qemu/module.h"
>>>    #include "qapi/error.h"
>>>    #include "exec/address-spaces.h"
>>> +#include "hw/acpi/acpi_aml_interface.h"
>>> +#include "hw/acpi/tpm.h"
>>>    #include "hw/qdev-properties.h"
>>>    #include "hw/pci/pci_ids.h"
>>>    #include "hw/acpi/tpm.h"
>>> @@ -121,6 +123,11 @@ static void tpm_crb_none_realize(DeviceState *dev, Error **errp)
>>>            return;
>>>        }
>>>
>>> +    if (tpm_crb_none_get_version(TPM_IF(s)) != TPM_VERSION_2_0) {
>>> +        error_setg(errp, "TPM CRB only supports TPM 2.0 backends");
>>> +        return;
>>> +    }
>>> +
>>>        tpm_crb_init_memory(OBJECT(s), &s->state, errp);
>>>
>>>        /* only used for migration */
>>> @@ -142,10 +149,17 @@ static void tpm_crb_none_realize(DeviceState *dev, Error **errp)
>>>        }
>>>    }
>>>
>>> +static void build_tpm_crb_none_aml(AcpiDevAmlIf *adev, Aml *scope)
>>> +{
>>> +    tpm_crb_build_aml(TPM_IF(adev), scope, TPM_CRB_ADDR_BASE, TPM_CRB_ADDR_SIZE,
>>> +                      true);
>>> +}
>>> +
>>>    static void tpm_crb_none_class_init(ObjectClass *klass, void *data)
>>>    {
>>>        DeviceClass *dc = DEVICE_CLASS(klass);
>>>        TPMIfClass *tc = TPM_IF_CLASS(klass);
>>> +    AcpiDevAmlIfClass *adevc = ACPI_DEV_AML_IF_CLASS(klass);
>>>
>>>        dc->realize = tpm_crb_none_realize;
>>>        device_class_set_props(dc, tpm_crb_none_properties);
>>> @@ -154,6 +168,7 @@ static void tpm_crb_none_class_init(ObjectClass *klass, void *data)
>>>        tc->model = TPM_MODEL_TPM_CRB;
>>>        tc->get_version = tpm_crb_none_get_version;
>>>        tc->request_completed = tpm_crb_none_request_completed;
>>> +    adevc->build_dev_aml = build_tpm_crb_none_aml;
>>>
>>>        set_bit(DEVICE_CATEGORY_MISC, dc->categories);
>>>    }
>>> @@ -166,6 +181,7 @@ static const TypeInfo tpm_crb_none_info = {
>>>        .class_init  = tpm_crb_none_class_init,
>>>        .interfaces = (InterfaceInfo[]) {
>>>            { TYPE_TPM_IF },
>>> +        { TYPE_ACPI_DEV_AML_IF },
>>>            { }
>>>        }
>>>    };
>>> diff --git a/hw/tpm/tpm_crb_common.c b/hw/tpm/tpm_crb_common.c
>>> index 605e8576e9..4fff0c6b59 100644
>>> --- a/hw/tpm/tpm_crb_common.c
>>> +++ b/hw/tpm/tpm_crb_common.c
>>> @@ -239,3 +239,22 @@ void tpm_crb_mem_load(TPMCRBState *s, const uint32_t *saved_regs,
>>>        memcpy(regs, saved_regs, TPM_CRB_R_MAX);
>>>        memcpy(&regs[R_CRB_DATA_BUFFER], saved_cmdmem, A_CRB_DATA_BUFFER);
>>>    }
>>> +
>>> +void tpm_crb_build_aml(TPMIf *ti, Aml *scope, uint32_t baseaddr, uint32_t size,
>>> +                       bool build_ppi)
>>> +{
>>> +    Aml *dev, *crs;
>>> +
>>> +    dev = aml_device("TPM");
>>> +    aml_append(dev, aml_name_decl("_HID", aml_string("MSFT0101")));
>>> +    aml_append(dev, aml_name_decl("_STR", aml_string("TPM 2.0 Device")));
>>> +    aml_append(dev, aml_name_decl("_UID", aml_int(1)));
>>> +    aml_append(dev, aml_name_decl("_STA", aml_int(0xF)));
>>> +    crs = aml_resource_template();
>>> +    aml_append(crs, aml_memory32_fixed(baseaddr, size, AML_READ_WRITE));
>>> +    aml_append(dev, aml_name_decl("_CRS", crs));
>>> +    if (build_ppi) {
>>> +        tpm_build_ppi_acpi(ti, dev);
>>> +    }
>>> +    aml_append(scope, dev);
>>> +}