fix(cpus): workaround for Neoverse N2 erratum 2340933

Neoverse N2 erratum 2340933 is a Cat B erratum that applies to
revision r0p0 and is fixed in r0p1. The workaround is to set
CPUACTLR5_EL1[61] to 1.

SDEN documentation:
https://developer.arm.com/documentation/SDEN-1982442/latest

Change-Id: I121add0dd35072c53392d33f049d893a5ff6354f
Signed-off-by: Bipin Ravi <bipin.ravi@arm.com>

4 files changed, 25 insertions, 9 deletions

diff --git a/docs/design/cpu-specific-build-macros.rst b/docs/design/cpu-specific-build-macros.rst
index 0b0184076..95497862f 100644
--- a/docs/design/cpu-specific-build-macros.rst
+++ b/docs/design/cpu-specific-build-macros.rst
@@ -655,6 +655,10 @@ For Neoverse N2, the following errata build flags are defined :
    CPU. This needs to be enabled for revision r0p0 of the CPU, it is fixed in
    r0p1.
 
+-  ``ERRATA_N2_2340933``: This applies errata 2340933 workaround to Neoverse-N2
+   CPU. This needs to be enabled for revision r0p0 of the CPU, it is fixed in
+   r0p1.
+
 -  ``ERRATA_N2_2346952``: This applies errata 2346952 workaround to Neoverse-N2
    CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2 of the CPU,
    it is fixed in r0p3.
diff --git a/lib/cpus/aarch64/neoverse_n2.S b/lib/cpus/aarch64/neoverse_n2.S
index f80115177..477522fed 100644
--- a/lib/cpus/aarch64/neoverse_n2.S
+++ b/lib/cpus/aarch64/neoverse_n2.S
@@ -165,6 +165,13 @@ workaround_runtime_end neoverse_n2, ERRATUM(2326639)
 
 check_erratum_ls neoverse_n2, ERRATUM(2326639), CPU_REV(0, 0)
 
+workaround_runtime_start neoverse_n2, ERRATUM(2340933), ERRATA_N2_2340933
+	/* Set bit 61 in CPUACTLR5_EL1 */
+	sysreg_bit_set NEOVERSE_N2_CPUACTLR5_EL1, BIT(61)
+workaround_runtime_end neoverse_n2, ERRATUM(2340933)
+
+check_erratum_ls neoverse_n2, ERRATUM(2340933), CPU_REV(0, 0)
+
 workaround_runtime_start neoverse_n2, ERRATUM(2346952), ERRATA_N2_2346952
 	/* Set TXREQ to STATIC and full L2 TQ size */
 	mrs	x1, NEOVERSE_N2_CPUECTLR2_EL1
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index 92c6aa491..39e90cae5 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -656,10 +656,14 @@ CPU_FLAG_LIST += ERRATA_N2_2242400
 # to revision r0p0 of the Neoverse N2 cpu and is fixed in r0p1.
 CPU_FLAG_LIST += ERRATA_N2_2280757
 
-# Flag to apply erraturm 2326639 workaroud during powerdown. This erratum
+# Flag to apply erratum 2326639 workaroud during powerdown. This erratum
 # applies to revision r0p0 of the Neoverse N2 cpu and is fixed in r0p1.
 CPU_FLAG_LIST += ERRATA_N2_2326639
 
+# Flag to apply erratum 2340933 workaroud during reset. This erratum
+# applies to revision r0p0 of the Neoverse N2 cpu and is fixed in r0p1.
+CPU_FLAG_LIST += ERRATA_N2_2340933
+
 # Flag to apply erratum 2346952 workaround during reset. This erratum applies
 # to r0p0, r0p1, r0p2 of the Neoverse N2 cpu, it is fixed in r0p3.
 CPU_FLAG_LIST += ERRATA_N2_2346952
diff --git a/services/std_svc/errata_abi/errata_abi_main.c b/services/std_svc/errata_abi/errata_abi_main.c
index 06c38721f..f2ca0d135 100644
--- a/services/std_svc/errata_abi/errata_abi_main.c
+++ b/services/std_svc/errata_abi/errata_abi_main.c
@@ -350,15 +350,16 @@ struct em_cpu_list cpu_list[] = {
 		[9] = {2242415, 0x00, 0x00, ERRATA_N2_2242415},
 		[10] = {2280757, 0x00, 0x00, ERRATA_N2_2280757},
 		[11] = {2326639, 0x00, 0x00, ERRATA_N2_2326639},
-		[12] = {2346952, 0x00, 0x02, ERRATA_N2_2346952},
-		[13] = {2376738, 0x00, 0x00, ERRATA_N2_2376738},
-		[14] = {2388450, 0x00, 0x00, ERRATA_N2_2388450},
-		[15] = {2728475, 0x00, 0x02, ERRATA_N2_2728475, \
+		[12] = {2340933, 0x00, 0x00, ERRATA_N2_2340933},
+		[13] = {2346952, 0x00, 0x02, ERRATA_N2_2346952},
+		[14] = {2376738, 0x00, 0x00, ERRATA_N2_2376738},
+		[15] = {2388450, 0x00, 0x00, ERRATA_N2_2388450},
+		[16] = {2728475, 0x00, 0x02, ERRATA_N2_2728475, \
 			ERRATA_NON_ARM_INTERCONNECT},
-		[16] = {2743014, 0x00, 0x02, ERRATA_N2_2743014},
-		[17] = {2743089, 0x00, 0x02, ERRATA_N2_2743089},
-		[18] = {2779511, 0x00, 0x02, ERRATA_N2_2779511},
-		[19 ... ERRATA_LIST_END] = UNDEF_ERRATA,
+		[17] = {2743014, 0x00, 0x02, ERRATA_N2_2743014},
+		[18] = {2743089, 0x00, 0x02, ERRATA_N2_2743089},
+		[19] = {2779511, 0x00, 0x02, ERRATA_N2_2779511},
+		[20 ... ERRATA_LIST_END] = UNDEF_ERRATA,
 	}
 },
 #endif /* NEOVERSE_N2_H_INC */