errata: workaround for Neoverse N2 erratum 2067956

Neoverse N2 erratum 2067956 is a Cat B erratum that applies to
revision r0p0 and is still open. The workaround is to set
CPUACTLR_EL1[46] to force L2 tag ECC inline correction mode.
This workaround works on revision r0p0.

SDEN can be found here:
https://developer.arm.com/documentation/SDEN1982442/latest

Signed-off-by: Bipin Ravi <bipin.ravi@arm.com>
Change-Id: Ie92d18a379c66675b5c1c50fd0b8dde130848b21
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index 73f977b..b8576e9 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -421,6 +421,10 @@
 # to revisions r0p0, r1p0 and r2p0 of the Cortex-A710 cpu and is still open.
 ERRATA_A710_2081180	?=0
 
+# Flag to apply erratum 2067956 workaround during reset. This erratum applies
+# to revision r0p0 of the Neoverse N2 cpu and is still open.
+ERRATA_N2_2067956	?=0
+
 # Flag to apply DSU erratum 798953. This erratum applies to DSUs revision r0p0.
 # Applying the workaround results in higher DSU power consumption on idle.
 ERRATA_DSU_798953	?=0
@@ -774,6 +778,10 @@
 $(eval $(call assert_boolean,ERRATA_A710_2081180))
 $(eval $(call add_define,ERRATA_A710_2081180))
 
+# Process ERRATA_N2_2067956 flag
+$(eval $(call assert_boolean,ERRATA_N2_2067956))
+$(eval $(call add_define,ERRATA_N2_2067956))
+
 # Process ERRATA_DSU_798953 flag
 $(eval $(call assert_boolean,ERRATA_DSU_798953))
 $(eval $(call add_define,ERRATA_DSU_798953))