Re: [Qemu-devel] [PATCH v8 3/5] acpi: add fw_cfg file for TPM and PPI virtual memory device

[Igor Mammedov <imammedo@redhat.com>]

On Mon, 16 Jul 2018 16:46:59 +0200
Igor Mammedov <imammedo@redhat.com> wrote:

> On Mon, 16 Jul 2018 14:59:46 +0200
> Marc-André Lureau <marcandre.lureau@redhat.com> wrote:
> 
> > From: Stefan Berger <stefanb@linux.vnet.ibm.com>
> > 
> > To avoid having to hard code the base address of the PPI virtual
> > memory device we introduce a fw_cfg file etc/tpm/config that holds the
> > base address of the PPI device, the version of the PPI interface and
> > the version of the attached TPM.

subj has nothing to do with acpi anymore, probably  we should change it to:

expose TPM/PPI configuration parameters to firmware via fw_cfg file 

> > Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
> > [ Marc-André: renamed to etc/tpm/config, made it static, document it ]
> > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> > ---
> >  include/hw/acpi/tpm.h |  3 +++
> >  hw/i386/acpi-build.c  | 19 +++++++++++++++++++
> >  docs/specs/tpm.txt    | 20 ++++++++++++++++++++
> >  3 files changed, 42 insertions(+)
> > 
> > diff --git a/include/hw/acpi/tpm.h b/include/hw/acpi/tpm.h
> > index b8796df916..a6109a97fc 100644
> > --- a/include/hw/acpi/tpm.h
> > +++ b/include/hw/acpi/tpm.h
> > @@ -194,4 +194,7 @@ REG32(CRB_DATA_BUFFER, 0x80)
> >  #define TPM_PPI_ADDR_SIZE           0x400
> >  #define TPM_PPI_ADDR_BASE           0xFED45000
> >  
> > +#define TPM_PPI_VERSION_NONE        0
> > +#define TPM_PPI_VERSION_1_30        1
> > +
> >  #endif /* HW_ACPI_TPM_H */
> > diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> > index 9e8350c55d..b19575681b 100644
> > --- a/hw/i386/acpi-build.c
> > +++ b/hw/i386/acpi-build.c
> > @@ -119,6 +119,12 @@ typedef struct AcpiBuildPciBusHotplugState {
> >      bool pcihp_bridge_en;
> >  } AcpiBuildPciBusHotplugState;
> >  
> > +typedef struct FWCfgTPMConfig {
> > +    uint32_t tpmppi_address;
> > +    uint8_t tpm_version;
> > +    uint8_t tpmppi_version;
> > +} QEMU_PACKED FWCfgTPMConfig;
> > +
> >  static void init_common_fadt_data(Object *o, AcpiFadtData *data)
> >  {
> >      uint32_t io = object_property_get_uint(o, ACPI_PM_PROP_PM_IO_BASE, NULL);
> > @@ -2873,6 +2879,8 @@ void acpi_setup(void)
> >      AcpiBuildTables tables;
> >      AcpiBuildState *build_state;
> >      Object *vmgenid_dev;
> > +    TPMIf *tpm;
> > +    static FWCfgTPMConfig tpm_config;
> >  
> >      if (!pcms->fw_cfg) {
> >          ACPI_BUILD_DPRINTF("No fw cfg. Bailing out.\n");
> > @@ -2907,6 +2915,17 @@ void acpi_setup(void)
> >      fw_cfg_add_file(pcms->fw_cfg, ACPI_BUILD_TPMLOG_FILE,
> >                      tables.tcpalog->data, acpi_data_len(tables.tcpalog));
> >  
> > +    tpm = tpm_find();
> > +    if (tpm && object_property_get_bool(OBJECT(tpm), "ppi", &error_abort)) {
> > +        tpm_config = (FWCfgTPMConfig) {
> > +            .tpmppi_address = cpu_to_le32(TPM_PPI_ADDR_BASE),
> > +            .tpm_version = tpm_get_version(tpm_find()),
> > +            .tpmppi_version = TPM_PPI_VERSION_NONE
> > +        };
> > +        fw_cfg_add_file(pcms->fw_cfg, "etc/tpm/config",
> > +                        &tpm_config, sizeof tpm_config);
> > +    }
> > +
> >      vmgenid_dev = find_vmgenid_dev();
> >      if (vmgenid_dev) {
> >          vmgenid_add_fw_cfg(VMGENID(vmgenid_dev), pcms->fw_cfg,
> > diff --git a/docs/specs/tpm.txt b/docs/specs/tpm.txt
> > index 0e9bbebe1d..de3f8bda56 100644
> > --- a/docs/specs/tpm.txt
> > +++ b/docs/specs/tpm.txt
> > @@ -20,6 +20,26 @@ QEMU files related to TPM TIS interface:
> >   - hw/tpm/tpm_tis.h
> >  
> >  
> > += fw_cfg interface =
> > +
> > +The bios/firmware may use the "etc/tpm/config" fw_cfg entry for  
> s/use/read/ to make clear fw may not write into it contract
> 
> > +configuring the guest appropriately.
> > +
> > +The entry of 6 bytes has the following content, in little-endian:
> > +
> > +    #define TPM_VERSION_UNSPEC          0
> > +    #define TPM_VERSION_1_2             1
> > +    #define TPM_VERSION_2_0             2
> > +
> > +    #define TPM_PPI_VERSION_NONE        0
> > +    #define TPM_PPI_VERSION_1_30        1
> > +
> > +    struct FWCfgTPMConfig {
> > +        uint32_t tpmppi_address;         /* PPI memory location */
> > +        uint8_t tpm_version;             /* TPM version */
> > +        uint8_t tpmppi_version;          /* PPI version */
> > +    };
> > +
> >  = ACPI Interface =
> >  
> >  The TPM device is defined with ACPI ID "PNP0C31". QEMU builds a SSDT and passes  
> 
>