fix(errata): workaround for Neoverse-N2 erratum 2138953

Neoverse-N2 erratum 2138953 is a Cat B erratum that applies to
revision r0p0 of CPU. It is still open. The workaround
is to write the value 4'b1001 to the PF_MODE bits in the
IMP_CPUECTLR2_EL1 register which will place the data prefetcher
in the most conservative mode instead of disabling it.

SDEN can be found here:

Signed-off-by: nayanpatel-arm <>
Change-Id: Ife0a4bece7ccf83cc99c1d5f5b5a43084bb69d64
4 files changed