errata: workaround for Neoverse N2 erratum 2138956

Neoverse N2 erratum 2138956 is a Cat B erratum that applies to
revision r0p0 and is still open. This erratum can be avoided by
inserting a sequence of 16 DMB ST instructions prior to WFI or WFE.

SDEN can be found here:

Signed-off-by: Bipin Ravi <>
Change-Id: I1aac87b3075992f875451e4767b21857f596d0b2
3 files changed