fix(cpus): workaround for Cortex-X4 erratum 3701758
Cortex-X4 erratum 3701758 that applies to r0p0, r0p1, r0p2 and r0p3
is still Open.
The workaround is for EL3 software that performs context save/restore
on a change of Security state to use a value of SCR_EL3.NS when
accessing ICH_VMCR_EL2 that reflects the Security state that owns the
data being saved or restored.
SDEN documentation:
https://developer.arm.com/documentation/109148/latest/
Change-Id: I4ee941d1e7653de7a12d69f538ca05f7f9f9961d
Signed-off-by: Govindraj Raja <govindraj.raja@arm.com>
diff --git a/lib/cpus/aarch64/cortex_x4.S b/lib/cpus/aarch64/cortex_x4.S
index 5765828..fded73f 100644
--- a/lib/cpus/aarch64/cortex_x4.S
+++ b/lib/cpus/aarch64/cortex_x4.S
@@ -23,6 +23,7 @@
#endif
.global check_erratum_cortex_x4_2726228
+.global check_erratum_cortex_x4_3701758
#if WORKAROUND_CVE_2022_23960
wa_cve_2022_23960_bhb_vector_table CORTEX_X4_BHB_LOOP_COUNT, cortex_x4
@@ -119,6 +120,10 @@
check_erratum_chosen cortex_x4, CVE(2024, 7881), WORKAROUND_CVE_2024_7881
+add_erratum_entry cortex_x4, ERRATUM(3701758), ERRATA_X4_3701758, NO_APPLY_AT_RESET
+
+check_erratum_ls cortex_x4, ERRATUM(3701758), CPU_REV(0, 3)
+
cpu_reset_func_start cortex_x4
/* Disable speculative loads */
msr SSBS, xzr
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index fb153f7..e782344 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -874,6 +874,11 @@
# to revisions r0p0 and r0p1 of the Cortex-X4 cpu. It is fixed in r0p2.
CPU_FLAG_LIST += ERRATA_X4_3076789
+# Flag to apply erratum 3701758 workaround during context save/restore of
+# ICH_VMCR_EL2 reg. This erratum applies to revisions r0p0, r0p1, r0p2 and r0p3
+# of the Cortex-X4 cpu and is still open.
+CPU_FLAG_LIST += ERRATA_X4_3701758
+
# Flag to apply erratum 1922240 workaround during reset. This erratum applies
# to revision r0p0 of the Cortex-A510 cpu and is fixed in r0p1.
CPU_FLAG_LIST += ERRATA_A510_1922240
diff --git a/lib/cpus/errata_common.c b/lib/cpus/errata_common.c
index f61d6e8..acb9fe3 100644
--- a/lib/cpus/errata_common.c
+++ b/lib/cpus/errata_common.c
@@ -100,6 +100,13 @@
break;
#endif /* ERRATA_X3_3701769 */
+#if ERRATA_X4_3701758
+ case EXTRACT_PARTNUM(CORTEX_X4_MIDR):
+ if (check_erratum_cortex_x4_3701758(cpu_get_rev_var()) == ERRATA_APPLIES)
+ return true;
+ break;
+#endif /* ERRATA_X4_3701758 */
+
default:
break;
}