tree 706f3276207ddeffb14858cefd07cedfc19b68ba
parent cc8cb065e8b0fc1a3509a854326599adf2870708
author Marcin Juszkiewicz <marcin.juszkiewicz@linaro.org> 1668606471 +0100
committer Marcin Juszkiewicz <marcin.juszkiewicz@linaro.org> 1668606506 +0100

fix(qemu-sbsa): enable SVE and SME

Commit 337ff4f1dd6604738d79fd3fa275ae74d74256b2 enabled SVE/SME for
qemu platform. Let do the same for qemu-sbsa one too.

With this change I can boot Debian 'bookworm' installed using Max cpu.

Info from referenced commit:

Starting with QEMU v3.1.0 (Dec 2018), QEMU's TCG emulation engine supports
the SVE architecture extension. In QEMU v7.1.0 (Aug 2022) it also gained
SME support.

As it stands today, running TF-A under QEMU with "-cpu max" makes Linux
hang, because SME and SVE accesses trap to EL3, but are never handled
there. This is because the Linux kernel sees the SVE or SME feature bits,
and assumes firmware has enabled the feature for lower exception levels.
This requirement is described in the Linux kernel booting protocol.

Enable those features in the TF-A build, so that BL31 does the proper
EL3 setup to make the feature usable in non-secure world.
We check the actual feature bits before accessing SVE or SME registers,
so this is safe even for older QEMU version or when not running with
-cpu max. As SVE and SME are AArch64 features only, do not enable them
when building for AArch32.

Signed-off-by: Marcin Juszkiewicz <marcin.juszkiewicz@linaro.org>
Change-Id: I9ea1f91e6b801218d944e8a7d798d5ae568ed59a