Commit 0fe24669 authored by Stefan Berger's avatar Stefan Berger Committed by Michael S. Tsirkin
Browse files

acpi: expose TPM/PPI configuration parameters to firmware via fw_cfg 



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.

Signed-off-by: default avatarStefan Berger <stefanb@linux.vnet.ibm.com>
[ Marc-André: renamed to etc/tpm/config, made it static, document it ]
Signed-off-by: default avatarMarc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: default avatarPhilippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Tested-by: default avatarStefan Berger <stefanb@linux.ibm.com>
Reviewed-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
parent 3b97c01e

docs/specs/tpm.txt

+19 −0
Original line number Diff line number Diff line
@@ -34,6 +34,25 @@ The CRB interface makes a memory mapped IO region in the area 0xfed40000 - 
QEMU files related to TPM CRB interface:

 - hw/tpm/tpm_crb.c



= fw_cfg interface =



The bios/firmware may read the "etc/tpm/config" fw_cfg entry for

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 =

hw/i386/acpi-build.c

+19 −0
Original line number Diff line number Diff line
@@ -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);
@@ -2847,6 +2853,8 @@ 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");
@@ -2881,6 +2889,17 @@ 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),

            .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,

include/hw/acpi/tpm.h

+3 −0
Original line number Diff line number Diff line
@@ -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 */