fix(cpus): workaround for Cortex-A76 erratum 2743102
Cortex-A76 erratum 2743102 is a Cat B erratum that applies to
all revisions <=r4p1 and is still open. The workaround is to
insert a dsb before the isb in the power down sequence.
SDEN documentation:
https://developer.arm.com/documentation/SDEN885749/latest
Signed-off-by: Bipin Ravi <bipin.ravi@arm.com>
Change-Id: Ie2cd73bd91417d30b5633d80b2fbee32944bc2de
diff --git a/docs/design/cpu-specific-build-macros.rst b/docs/design/cpu-specific-build-macros.rst
index 37120c9..03b3ee5 100644
--- a/docs/design/cpu-specific-build-macros.rst
+++ b/docs/design/cpu-specific-build-macros.rst
@@ -256,6 +256,10 @@
- ``ERRATA_A76_1946160``: This applies errata 1946160 workaround to Cortex-A76
CPU. This needs to be enabled only for revisions r3p0 - r4p1 of the CPU.
+- ``ERRATA_A76_2743102``: This applies errata 2743102 workaround to Cortex-A76
+ CPU. This needs to be enabled for all revisions <= r4p1 of the CPU and is
+ still open.
+
For Cortex-A77, the following errata build flags are defined :
- ``ERRATA_A77_1508412``: This applies errata 1508412 workaround to Cortex-A77
diff --git a/lib/cpus/aarch64/cortex_a76.S b/lib/cpus/aarch64/cortex_a76.S
index 6d4017a..36507de 100644
--- a/lib/cpus/aarch64/cortex_a76.S
+++ b/lib/cpus/aarch64/cortex_a76.S
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2017-2020, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2017-2022, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@@ -586,6 +586,30 @@
b cpu_rev_var_range
endfunc check_errata_1946160
+ /* ----------------------------------------------------
+ * Errata Workaround for Cortex-A76 Errata #2743102
+ * This applies to revisions <= r4p1 and is still open.
+ * x0: variant[4:7] and revision[0:3] of current cpu.
+ * Shall clobber: x0-x17
+ * ----------------------------------------------------
+ */
+func errata_a76_2743102_wa
+ mov x17, x30
+ bl check_errata_2743102
+ cbz x0, 1f
+
+ /* dsb before isb of power down sequence */
+ dsb sy
+1:
+ ret x17
+endfunc errata_a76_2743102_wa
+
+func check_errata_2743102
+ /* Applies to all revisions <= r4p1 */
+ mov x1, #0x41
+ b cpu_rev_var_ls
+endfunc check_errata_2743102
+
func check_errata_cve_2018_3639
#if WORKAROUND_CVE_2018_3639
mov x0, #ERRATA_APPLIES
@@ -748,6 +772,12 @@
mrs x0, CORTEX_A76_CPUPWRCTLR_EL1
orr x0, x0, #CORTEX_A76_CORE_PWRDN_EN_MASK
msr CORTEX_A76_CPUPWRCTLR_EL1, x0
+#if ERRATA_A76_2743102
+ mov x15, x30
+ bl cpu_get_rev_var
+ bl errata_a76_2743102_wa
+ mov x30, x15
+#endif /* ERRATA_A76_2743102 */
isb
ret
endfunc cortex_a76_core_pwr_dwn
@@ -768,6 +798,7 @@
*/
report_errata ERRATA_A76_1073348, cortex_a76, 1073348
report_errata ERRATA_A76_1130799, cortex_a76, 1130799
+ report_errata ERRATA_A76_1165522, cortex_a76, 1165522
report_errata ERRATA_A76_1220197, cortex_a76, 1220197
report_errata ERRATA_A76_1257314, cortex_a76, 1257314
report_errata ERRATA_A76_1262606, cortex_a76, 1262606
@@ -775,9 +806,9 @@
report_errata ERRATA_A76_1275112, cortex_a76, 1275112
report_errata ERRATA_A76_1286807, cortex_a76, 1286807
report_errata ERRATA_A76_1791580, cortex_a76, 1791580
- report_errata ERRATA_A76_1165522, cortex_a76, 1165522
report_errata ERRATA_A76_1868343, cortex_a76, 1868343
report_errata ERRATA_A76_1946160, cortex_a76, 1946160
+ report_errata ERRATA_A76_2743102, cortex_a76, 2743102
report_errata WORKAROUND_CVE_2018_3639, cortex_a76, cve_2018_3639
report_errata ERRATA_DSU_798953, cortex_a76, dsu_798953
report_errata ERRATA_DSU_936184, cortex_a76, dsu_936184
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index f53bad1..eb6d20f 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -287,6 +287,10 @@
# only to revisions r3p0 - r4p1 of the Cortex A76 cpu.
ERRATA_A76_1946160 ?=0
+# Flag to apply erratum 2743102 workaround during powerdown. This erratum
+# applies to all revisions <= r4p1 of the Cortex A76 cpu and is still open.
+ERRATA_A76_2743102 ?=0
+
# Flag to apply erratum 1508412 workaround during reset. This erratum applies
# only to revision <= r1p0 of the Cortex A77 cpu.
ERRATA_A77_1508412 ?=0
@@ -916,6 +920,10 @@
$(eval $(call assert_boolean,ERRATA_A76_1946160))
$(eval $(call add_define,ERRATA_A76_1946160))
+# Process ERRATA_A76_2743102 flag
+$(eval $(call assert_boolean,ERRATA_A76_2743102))
+$(eval $(call add_define,ERRATA_A76_2743102))
+
# Process ERRATA_A77_1508412 flag
$(eval $(call assert_boolean,ERRATA_A77_1508412))
$(eval $(call add_define,ERRATA_A77_1508412))