arch-arm: Allow TLB to be used as a WalkCache

This patch allows partial translation entries (intermediate PAs obtained
from a table walk) to be stored in an ArmTLB. This effectively means
reserving a fraction of the TLB entries to cache table walks

JIRA: https://gem5.atlassian.net/browse/GEM5-1108

Change-Id: Id0efb7d75dd017366c4c3b74de7b57355a53a01a
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/52124
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
5 files changed