docs/system/ppc: Merge the PEF information into the pseries page

The Protected Execution Facility is only available with the pseries
machine, so let's merge the old ASCII text into the new RST file now.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220105103232.405204-1-thuth@redhat.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>

docs/papr-pef.txt

-POWER (PAPR) Protected Execution Facility (PEF)
-===============================================
-
-Protected Execution Facility (PEF), also known as Secure Guest support
-is a feature found on IBM POWER9 and POWER10 processors.
-
-If a suitable firmware including an Ultravisor is installed, it adds
-an extra memory protection mode to the CPU.  The ultravisor manages a
-pool of secure memory which cannot be accessed by the hypervisor.
-
-When this feature is enabled in QEMU, a guest can use ultracalls to
-enter "secure mode".  This transfers most of its memory to secure
-memory, where it cannot be eavesdropped by a compromised hypervisor.
-
-Launching
----------
-
-To launch a guest which will be permitted to enter PEF secure mode:
-
-# ${QEMU} \
-    -object pef-guest,id=pef0 \
-    -machine confidential-guest-support=pef0 \
-    ...
-
-Live Migration
-----------------
-
-Live migration is not yet implemented for PEF guests.  For
-consistency, we currently prevent migration if the PEF feature is
-enabled, whether or not the guest has actually entered secure mode.

docs/system/ppc/pseries.rst

@@ -230,6 +230,39 @@ nested. Combinations not shown in the table are not available.
 
 .. [3] Introduced on Power10 machines.
 
+
+POWER (PAPR) Protected Execution Facility (PEF)
+-----------------------------------------------
+
+Protected Execution Facility (PEF), also known as Secure Guest support
+is a feature found on IBM POWER9 and POWER10 processors.
+
+If a suitable firmware including an Ultravisor is installed, it adds
+an extra memory protection mode to the CPU.  The ultravisor manages a
+pool of secure memory which cannot be accessed by the hypervisor.
+
+When this feature is enabled in QEMU, a guest can use ultracalls to
+enter "secure mode".  This transfers most of its memory to secure
+memory, where it cannot be eavesdropped by a compromised hypervisor.
+
+Launching
+^^^^^^^^^
+
+To launch a guest which will be permitted to enter PEF secure mode::
+
+  $ qemu-system-ppc64 \
+      -object pef-guest,id=pef0 \
+      -machine confidential-guest-support=pef0 \
+      ...
+
+Live Migration
+^^^^^^^^^^^^^^
+
+Live migration is not yet implemented for PEF guests.  For
+consistency, QEMU currently prevents migration if the PEF feature is
+enabled, whether or not the guest has actually entered secure mode.
+
+
 Maintainer contact information
 ------------------------------