tree b7b605fd74c9435143d6c3464d4c829e95ea8141
parent cba6ac4869e45cc93ac5497024d1d49576e82666
author Michael Ellerman <mpe@ellerman.id.au> 1507803438 +1100
committer Michael Ellerman <mpe@ellerman.id.au> 1508538785 +1100

powerpc/powernv: Enable TM without suspend if possible

Some Power9 revisions can run in a mode where TM operates without
suspended state. If we find ourself on a CPU that might be in this
mode, we query OPAL to check, and if so we reenable TM in CPU
features, and enable a new user feature to signal to userspace that we
are in this mode.

We do not enable the "normal" user feature, PPC_FEATURE2_HTM, but we
do enable PPC_FEATURE2_HTM_NOSC because that indicates to userspace
that the kernel will abort transactions on syscall entry, which is
true regardless of the suspend mode.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>