errata: workaround for Neoverse V1 errata 1966096
Neoverse V1 erratum 1966096 is a Cat B erratum present in the V1
processor core. This issue is present in revisions r0p0, r1p0,
and r1p1, but the workaround only applies to r1p0 and r1p1, it is still
open.
SDEN can be found here:
https://documentation-service.arm.com/static/60d499080320e92fa40b4625
Signed-off-by: John Powell <john.powell@arm.com>
Change-Id: Ic0b9a931e38da8a7000648e221481e17c253563b
diff --git a/docs/design/cpu-specific-build-macros.rst b/docs/design/cpu-specific-build-macros.rst
index aa1a247..4d7b179 100644
--- a/docs/design/cpu-specific-build-macros.rst
+++ b/docs/design/cpu-specific-build-macros.rst
@@ -344,6 +344,11 @@
CPU. This needs to be enabled only for revision r1p0 and r1p1 of the
CPU.
+- ``ERRATA_V1_1966096``: This applies errata 1966096 workaround to Neoverse-V1
+ CPU. This needs to be enabled for revisions r1p0 and r1p1 of the CPU, the
+ issue is present in r0p0 as well but there is no workaround for that
+ revision. It is still open.
+
DSU Errata Workarounds
----------------------
diff --git a/lib/cpus/aarch64/neoverse_v1.S b/lib/cpus/aarch64/neoverse_v1.S
index 2e088a1..f202027 100644
--- a/lib/cpus/aarch64/neoverse_v1.S
+++ b/lib/cpus/aarch64/neoverse_v1.S
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2019-2021, ARM Limited. All rights reserved.
+ * Copyright (c) 2019-2021, Arm Limited. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@@ -188,6 +188,42 @@
b cpu_rev_var_range
endfunc check_errata_1940577
+ /* --------------------------------------------------
+ * Errata Workaround for Neoverse V1 Errata #1966096
+ * This applies to revisions r1p0 - r1p1 and is open.
+ * It also exists in r0p0 but there is no workaround
+ * for that revision.
+ * x0: variant[4:7] and revision[0:3] of current cpu.
+ * Shall clobber: x0-x17
+ * --------------------------------------------------
+ */
+func errata_neoverse_v1_1966096_wa
+ /* Check workaround compatibility. */
+ mov x17, x30
+ bl check_errata_1966096
+ cbz x0, 1f
+
+ /* Apply the workaround. */
+ mov x0, #0x3
+ msr S3_6_C15_C8_0, x0
+ ldr x0, =0xEE010F12
+ msr S3_6_C15_C8_2, x0
+ ldr x0, =0xFFFF0FFF
+ msr S3_6_C15_C8_3, x0
+ ldr x0, =0x80000000003FF
+ msr S3_6_C15_C8_1, x0
+ isb
+
+1:
+ ret x17
+endfunc errata_neoverse_v1_1966096_wa
+
+func check_errata_1966096
+ mov x1, #0x10
+ mov x2, #0x11
+ b cpu_rev_var_range
+endfunc check_errata_1966096
+
/* ---------------------------------------------
* HW will do the cache maintenance while powering down
* ---------------------------------------------
@@ -223,6 +259,7 @@
report_errata ERRATA_V1_1852267, neoverse_v1, 1852267
report_errata ERRATA_V1_1925756, neoverse_v1, 1925756
report_errata ERRATA_V1_1940577, neoverse_v1, 1940577
+ report_errata ERRATA_V1_1966096, neoverse_v1, 1966096
ldp x8, x30, [sp], #16
ret
@@ -261,6 +298,11 @@
bl errata_neoverse_v1_1940577_wa
#endif
+#if ERRATA_V1_1966096
+ mov x0, x18
+ bl errata_neoverse_v1_1966096_wa
+#endif
+
ret x19
endfunc neoverse_v1_reset_func
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index f482932..4677f91 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -392,6 +392,11 @@
# to revisions r1p0 and r1p1 of the Neoverse V1 cpu.
ERRATA_V1_1940577 ?=0
+# Flag to apply erratum 1966096 workaround during reset. This erratum applies
+# to revisions r1p0 and r1p1 of the Neoverse V1 CPU and is open. This issue
+# exists in r0p0 as well but there is no workaround for that revision.
+ERRATA_V1_1966096 ?=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
@@ -717,6 +722,10 @@
$(eval $(call assert_boolean,ERRATA_V1_1940577))
$(eval $(call add_define,ERRATA_V1_1940577))
+# Process ERRATA_V1_1966096 flag
+$(eval $(call assert_boolean,ERRATA_V1_1966096))
+$(eval $(call add_define,ERRATA_V1_1966096))
+
# Process ERRATA_DSU_798953 flag
$(eval $(call assert_boolean,ERRATA_DSU_798953))
$(eval $(call add_define,ERRATA_DSU_798953))