errata: workaround for Cortex-A710 errata 1987031
Cortex-A710 erratum 1987031 is a Cat B erratum present in r0p0, r1p0,
and r2p0 of the Cortex-A710 processor core, and it is still open.
A710 SDEN: https://documentation-service.arm.com/static/61099dc59ebe3a7dbd3a8a88?token=
Signed-off-by: nayanpatel-arm <nayankumar.patel@arm.com>
Change-Id: I9bcff306f82328ad5a0f6e9836020d23c07f7179
diff --git a/docs/design/cpu-specific-build-macros.rst b/docs/design/cpu-specific-build-macros.rst
index 0a0d2f0..194b6c6 100644
--- a/docs/design/cpu-specific-build-macros.rst
+++ b/docs/design/cpu-specific-build-macros.rst
@@ -359,6 +359,12 @@
CPU. This needs to be enabled for revisions r0p0, r1p0, and r1p1 of the
CPU. It is still open.
+For Cortex-A710, the following errata build flags are defined :
+
+- ``ERRATA_A710_1987031``: This applies errata 1987031 workaround to
+ Cortex-A710 CPU. This needs to be enabled only for revisions r0p0, r1p0 and
+ r2p0 of the CPU. It is still open.
+
DSU Errata Workarounds
----------------------
diff --git a/lib/cpus/aarch64/cortex_a710.S b/lib/cpus/aarch64/cortex_a710.S
index 4f979f8..3970035 100644
--- a/lib/cpus/aarch64/cortex_a710.S
+++ b/lib/cpus/aarch64/cortex_a710.S
@@ -21,6 +21,49 @@
#error "Cortex A710 supports only AArch64. Compile with CTX_INCLUDE_AARCH32_REGS=0"
#endif
+/* --------------------------------------------------
+ * Errata Workaround for Cortex-A710 Erratum 1987031.
+ * This applies to revision r0p0, r1p0 and r2p0 of Cortex-A710. It is still
+ * open.
+ * Inputs:
+ * x0: variant[4:7] and revision[0:3] of current cpu.
+ * Shall clobber: x0-x17
+ * --------------------------------------------------
+ */
+func errata_a710_1987031_wa
+ /* Check revision. */
+ mov x17, x30
+ bl check_errata_1987031
+ cbz x0, 1f
+
+ /* Apply instruction patching sequence */
+ ldr x0,=0x6
+ msr S3_6_c15_c8_0,x0
+ ldr x0,=0xF3A08002
+ msr S3_6_c15_c8_2,x0
+ ldr x0,=0xFFF0F7FE
+ msr S3_6_c15_c8_3,x0
+ ldr x0,=0x40000001003ff
+ msr S3_6_c15_c8_1,x0
+ ldr x0,=0x7
+ msr S3_6_c15_c8_0,x0
+ ldr x0,=0xBF200000
+ msr S3_6_c15_c8_2,x0
+ ldr x0,=0xFFEF0000
+ msr S3_6_c15_c8_3,x0
+ ldr x0,=0x40000001003f3
+ msr S3_6_c15_c8_1,x0
+ isb
+1:
+ ret x17
+endfunc errata_a710_1987031_wa
+
+func check_errata_1987031
+ /* Applies to r0p0, r1p0 and r2p0 */
+ mov x1, #0x20
+ b cpu_rev_var_ls
+endfunc check_errata_1987031
+
/* ----------------------------------------------------
* HW will do the cache maintenance while powering down
* ----------------------------------------------------
@@ -42,15 +85,38 @@
*/
#if REPORT_ERRATA
func cortex_a710_errata_report
+ stp x8, x30, [sp, #-16]!
+
+ bl cpu_get_rev_var
+ mov x8, x0
+
+ /*
+ * Report all errata. The revision-variant information is passed to
+ * checking functions of each errata.
+ */
+ report_errata ERRATA_A710_1987031, cortex_a710, 1987031
+
+ ldp x8, x30, [sp], #16
ret
endfunc cortex_a710_errata_report
#endif
func cortex_a710_reset_func
+ mov x19, x30
+
/* Disable speculative loads */
msr SSBS, xzr
+
+ bl cpu_get_rev_var
+ mov x18, x0
+
+#if ERRATA_A710_1987031
+ mov x0, x18
+ bl errata_a710_1987031_wa
+#endif
+
isb
- ret
+ ret x19
endfunc cortex_a710_reset_func
/* ---------------------------------------------
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index b366167..ed507c8 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -405,6 +405,10 @@
# to revisions r0p0, r1p0, and r1p1 of the Neoverse V1 cpu and is still open.
ERRATA_V1_2139242 ?=0
+# Flag to apply erratum 1987031 workaround during reset. This erratum applies
+# to revisions r0p0, r1p0 and r2p0 of the Cortex-A710 cpu and is still open.
+ERRATA_A710_1987031 ?=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
@@ -742,6 +746,10 @@
$(eval $(call assert_boolean,ERRATA_V1_2139242))
$(eval $(call add_define,ERRATA_V1_2139242))
+# Process ERRATA_A710_1987031 flag
+$(eval $(call assert_boolean,ERRATA_A710_1987031))
+$(eval $(call add_define,ERRATA_A710_1987031))
+
# Process ERRATA_DSU_798953 flag
$(eval $(call assert_boolean,ERRATA_DSU_798953))
$(eval $(call add_define,ERRATA_DSU_798953))