Workaround for Neoverse N1 erratum 1220197

Neoverse N1 erratum 1220197 is a Cat B erratum [1],
present in older revisions of the Neoverse N1 processor core.
The workaround is to set two bits in the implementation defined
CPUECTLR_EL1 system register, which disables write streaming to the L2.

[1] http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.pjdoc-466751330-10325/index.html

Change-Id: I9c3373f1b6d67d21ee71b2b80aec5e96826818e8
Signed-off-by: Lauren Wehrmeister <lauren.wehrmeister@arm.com>
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index 78efbeb..bb53dad 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -254,6 +254,10 @@
 # only to revision <= r2p0 of the Neoverse N1 cpu.
 ERRATA_N1_1207823	?=0
 
+# Flag to apply erratum 1220197 workaround during reset. This erratum applies
+# only to revision <= r2p0 of the Neoverse N1 cpu.
+ERRATA_N1_1220197	?=0
+
 # Flag to apply erratum 1315703 workaround during reset. This erratum applies
 # to revisions before r3p1 of the Neoverse N1 cpu.
 ERRATA_N1_1315703	?=1
@@ -463,6 +467,10 @@
 $(eval $(call assert_boolean,ERRATA_N1_1207823))
 $(eval $(call add_define,ERRATA_N1_1207823))
 
+# Process ERRATA_N1_1220197 flag
+$(eval $(call assert_boolean,ERRATA_N1_1220197))
+$(eval $(call add_define,ERRATA_N1_1220197))
+
 # Process ERRATA_N1_1315703 flag
 $(eval $(call assert_boolean,ERRATA_N1_1315703))
 $(eval $(call add_define,ERRATA_N1_1315703))