docs: Fix information for default TPM version

The current information is not accurate, because the default
is 2.0 instead of 1.2 for the tpm-crb and tpm-spapr models.

Any detailed list will surely become obsolete and out of sync
with reality over time, so let's just document that the default
model depends on a number of factors and avoid getting any more
specific than that.

Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Tested-by: Liu Yiding <liuyd.fnst@fujitsu.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>

diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst
index c6dede053f67dad8175118badbaca31a05e533b6..25e6bf73ba1c7ff43506a5165a9c9c21a0f4013d 100644 (file)
--- a/docs/formatdomain.rst
+++ b/docs/formatdomain.rst
@@ -7540,13 +7540,16 @@ Example: usage of the TPM Emulator
       each QEMU guest requesting access to it.
 
 ``version``
-   The ``version`` attribute indicates the version of the TPM. By default a TPM
-   1.2 is created. This attribute only works with the ``emulator`` backend. The
-   following versions are supported:
+   The ``version`` attribute indicates the version of the TPM. This attribute
+   only works with the ``emulator`` backend. The following versions are
+   supported:
 
    -  '1.2' : creates a TPM 1.2
    -  '2.0' : creates a TPM 2.0
 
+   The default version used depends on the combination of hypervisor, guest
+   architecture, TPM model and backend.
+
 ``persistent_state``
    The ``persistent_state`` attribute indicates whether 'swtpm' TPM state is
    kept or not when a transient domain is powered off or undefined. This