fix(cpus): workaround for Cortex-A78 erratum 2772019
Cortex-A78 erratum 2772019 is a Cat B erratum that applies to
all revisions <=r1p2 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/SDEN1401784/latest
Signed-off-by: Bipin Ravi <bipin.ravi@arm.com>
Change-Id: I0362da463eca777aa7a385bcdeb39b8549799f02
diff --git a/docs/design/cpu-specific-build-macros.rst b/docs/design/cpu-specific-build-macros.rst
index ac2db09..e56eac1 100644
--- a/docs/design/cpu-specific-build-macros.rst
+++ b/docs/design/cpu-specific-build-macros.rst
@@ -317,6 +317,10 @@
CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1, and r1p2, and
it is still open.
+- ``ERRATA_A78_2772019``: This applies errata 2772019 workaround to Cortex-A78
+ CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1, and r1p2, and
+ it is still open.
+
For Cortex-A78 AE, the following errata build flags are defined :
- ``ERRATA_A78_AE_1941500`` : This applies errata 1941500 workaround to
diff --git a/lib/cpus/aarch64/cortex_a78.S b/lib/cpus/aarch64/cortex_a78.S
index dd3487a..38f58bb 100644
--- a/lib/cpus/aarch64/cortex_a78.S
+++ b/lib/cpus/aarch64/cortex_a78.S
@@ -326,6 +326,31 @@
b cpu_rev_var_ls
endfunc check_errata_2395406
+/* ----------------------------------------------------
+ * Errata Workaround for Cortex-A78 Errata 2772019
+ * This applies to revisions <= r1p2 and is still open.
+ * x0: variant[4:7] and revision[0:3] of current cpu.
+ * Shall clobber: x0-x17
+ * ----------------------------------------------------
+ */
+func errata_a78_2772019_wa
+ mov x17, x30
+ bl check_errata_2772019
+ cbz x0, 1f
+
+
+ /* dsb before isb of power down sequence */
+ dsb sy
+1:
+ ret x17
+endfunc errata_a78_2772019_wa
+
+func check_errata_2772019
+ /* Applies to all revisions <= r1p2 */
+ mov x1, #0x12
+ b cpu_rev_var_ls
+endfunc check_errata_2772019
+
func check_errata_cve_2022_23960
#if WORKAROUND_CVE_2022_23960
mov x0, #ERRATA_APPLIES
@@ -434,6 +459,12 @@
mrs x0, CORTEX_A78_CPUPWRCTLR_EL1
orr x0, x0, #CORTEX_A78_CPUPWRCTLR_EL1_CORE_PWRDN_EN_BIT
msr CORTEX_A78_CPUPWRCTLR_EL1, x0
+#if ERRATA_A78_2772019
+ mov x15, x30
+ bl cpu_get_rev_var
+ bl errata_a78_2772019_wa
+ mov x30, x15
+#endif /* ERRATA_A78_2772019 */
isb
ret
endfunc cortex_a78_core_pwr_dwn
@@ -461,6 +492,7 @@
report_errata ERRATA_A78_2242635, cortex_a78, 2242635
report_errata ERRATA_A78_2376745, cortex_a78, 2376745
report_errata ERRATA_A78_2395406, cortex_a78, 2395406
+ report_errata ERRATA_A78_2772019, cortex_a78, 2772019
report_errata WORKAROUND_CVE_2022_23960, cortex_a78, cve_2022_23960
ldp x8, x30, [sp], #16
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index 69c474e..2d7ccc0 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -357,6 +357,11 @@
# to revisions r0p0, r1p0, r1p1, and r1p2 of the A78 cpu. It is still open.
ERRATA_A78_2395406 ?=0
+# Flag to apply erratum 2772019 workaround during powerdown. This erratum
+# applies to revisions r0p0, r1p0, r1p1 and r1p2 of the A78 cpu. It is still
+# open.
+ERRATA_A78_2772019 ?=0
+
# Flag to apply erratum 1941500 workaround during reset. This erratum applies
# to revisions r0p0 and r0p1 of the A78 AE cpu. It is still open.
ERRATA_A78_AE_1941500 ?=0
@@ -1011,6 +1016,10 @@
$(eval $(call assert_boolean,ERRATA_A78_2395406))
$(eval $(call add_define,ERRATA_A78_2395406))
+# Process ERRATA_A78_2772019 flag
+$(eval $(call assert_boolean,ERRATA_A78_2772019))
+$(eval $(call add_define,ERRATA_A78_2772019))
+
# Process ERRATA_A78_AE_1941500 flag
$(eval $(call assert_boolean,ERRATA_A78_AE_1941500))
$(eval $(call add_define,ERRATA_A78_AE_1941500))