fix(cpus): workaround for Neoverse N2 erratum 2346952
Neoverse N2 erratum 2346952 is a Cat B erratum that applies to all
revisions <= r0p2 and is fixed in r0p3.
The workaround is to set L2 TQ size statically to it's full size.
SDEN documentation:
https://developer.arm.com/documentation/SDEN-1982442/latest
Change-Id: I03c3cf1f951fbc906fdebcb99a523c5ac8ba055d
Signed-off-by: Bipin Ravi <bipin.ravi@arm.com>
diff --git a/lib/cpus/aarch64/neoverse_n2.S b/lib/cpus/aarch64/neoverse_n2.S
index ead3908..f801151 100644
--- a/lib/cpus/aarch64/neoverse_n2.S
+++ b/lib/cpus/aarch64/neoverse_n2.S
@@ -165,6 +165,16 @@
check_erratum_ls neoverse_n2, ERRATUM(2326639), 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
+ mov x0, #CPUECTLR2_EL1_TXREQ_STATIC_FULL
+ bfi x1, x0, #CPUECTLR2_EL1_TXREQ_LSB, #CPUECTLR2_EL1_TXREQ_WIDTH
+ msr NEOVERSE_N2_CPUECTLR2_EL1, x1
+workaround_runtime_end neoverse_n2, ERRATUM(2346952)
+
+check_erratum_ls neoverse_n2, ERRATUM(2346952), CPU_REV(0, 2)
+
workaround_reset_start neoverse_n2, ERRATUM(2376738), ERRATA_N2_2376738
/* Set CPUACTLR2_EL1[0] to 1 to force PLDW/PFRM
* ST to behave like PLD/PFRM LD and not cause
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index ea29047..92c6aa4 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -660,6 +660,10 @@
# applies to revision r0p0 of the Neoverse N2 cpu and is fixed in r0p1.
CPU_FLAG_LIST += ERRATA_N2_2326639
+# 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
+
# Flag to apply erratum 2376738 workaround during reset. This erratum applies
# to revision r0p0, r0p1, r0p2, r0p3 of the Neoverse N2 cpu and is still open.
CPU_FLAG_LIST += ERRATA_N2_2376738