fix(cpus): workaround for Neoverse-N2 erratum 2326639
Neoverse-N2 erratum 2326639 is a Cat B erratum that applies to revision
r0p0 and is fixed in r0p1. The workaround is to set CPUACTLR2_EL1[36] to
1 before the power down sequence that sets CORE_PWRDN_EN. This allows
the cpu to retry the power down and prevents the deadlock. TF-A never
clears this bit even if it wakes up from the wfi in the sequence since
it is not expected to do anything but retry to power down after and the
bit is cleared on reset.
SDEN can be found here:
https://developer.arm.com/documentation/SDEN1982442/latest/
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
Change-Id: I9a325c5b9b498798e5efd5c79a4a6d5bed97c619
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index ec0d95e..2c42ad0 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -592,6 +592,10 @@
# to revision r0p0 of the Neoverse N2 cpu and is still open.
ERRATA_N2_2280757 ?=0
+# Flag to apply erraturm 2326639 workaroud during powerdown. This erratum
+# applies to revision r0p0 of the Neoverse N2 cpu and is fixed in r0p1.
+ERRATA_N2_2326639 ?=0
+
# Flag to apply erratum 2376738 workaround during reset. This erratum applies
# to revision r0p0 of the Neoverse N2 cpu, it is fixed in r0p1.
ERRATA_N2_2376738 ?=0
@@ -1200,6 +1204,10 @@
$(eval $(call assert_boolean,ERRATA_N2_2280757))
$(eval $(call add_define,ERRATA_N2_2280757))
+# Process ERRATA_N2_2326639 flag
+$(eval $(call assert_boolean,ERRATA_N2_2326639))
+$(eval $(call add_define,ERRATA_N2_2326639))
+
# Process ERRATA_N2_2376738 flag
$(eval $(call assert_boolean,ERRATA_N2_2376738))
$(eval $(call add_define,ERRATA_N2_2376738))