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/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