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authorStefan Berger <stefanb@linux.vnet.ibm.com>2019-01-15 02:27:51 +0400
committerMichael S. Tsirkin <mst@redhat.com>2019-01-17 21:10:57 -0500
commit0fe246690315335a40a132f05cb6fdc7bfb9adca (patch)
tree34e9f189fb2c6a4da96533184fd88f6cd5681a78 /docs
parent3b97c01e9ccdfbd517a0fd631838d6252dbfa692 (diff)
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: 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> Acked-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Tested-by: Stefan Berger <stefanb@linux.ibm.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'docs')
-rw-r--r--docs/specs/tpm.txt19
1 files changed, 19 insertions, 0 deletions
diff --git a/docs/specs/tpm.txt b/docs/specs/tpm.txt
index 1af82bba86..e4bb094700 100644
--- a/docs/specs/tpm.txt
+++ b/docs/specs/tpm.txt
@@ -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 =