Workaround for Cortex A77 erratum 1508412
Cortex A77 erratum 1508412 is a Cat B Errata present in r0p0 and r1p0.
The workaround is a write sequence to several implementation defined
registers based on A77 revision.
This errata is explained in this SDEN:
https://static.docs.arm.com/101992/0010/Arm_Cortex_A77_MP074_Software_Developer_Errata_Notice_v10.pdf
Signed-off-by: Lauren Wehrmeister <lauren.wehrmeister@arm.com>
Change-Id: I217993cffb3ac57c313db8490e7b8a7bb393379b
diff --git a/docs/design/cpu-specific-build-macros.rst b/docs/design/cpu-specific-build-macros.rst
index 3c0e30f..e9ff17e 100644
--- a/docs/design/cpu-specific-build-macros.rst
+++ b/docs/design/cpu-specific-build-macros.rst
@@ -251,6 +251,9 @@
For Cortex-A77, the following errata build flags are defined :
+- ``ERRATA_A77_1508412``: This applies errata 1508412 workaround to Cortex-A77
+ CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
+
- ``ERRATA_A77_1800714``: This applies errata 1800714 workaround to Cortex-A77
CPU. This needs to be enabled only for revision <= r1p1 of the CPU.
diff --git a/include/lib/cpus/aarch64/cortex_a77.h b/include/lib/cpus/aarch64/cortex_a77.h
index bbd647c..41aced8 100644
--- a/include/lib/cpus/aarch64/cortex_a77.h
+++ b/include/lib/cpus/aarch64/cortex_a77.h
@@ -24,4 +24,11 @@
#define CORTEX_A77_CPUPWRCTLR_EL1 S3_0_C15_C2_7
#define CORTEX_A77_CPUPWRCTLR_EL1_CORE_PWRDN_BIT (U(1) << 0)
+#define CORTEX_A77_CPUPSELR_EL3 S3_6_C15_C8_0
+#define CORTEX_A77_CPUPCR_EL3 S3_6_C15_C8_1
+#define CORTEX_A77_CPUPOR_EL3 S3_6_C15_C8_2
+#define CORTEX_A77_CPUPMR_EL3 S3_6_C15_C8_3
+#define CORTEX_A77_CPUPOR2_EL3 S3_6_C15_C8_4
+#define CORTEX_A77_CPUPMR2_EL3 S3_6_C15_C8_5
+
#endif /* CORTEX_A77_H */
diff --git a/lib/cpus/aarch64/cortex_a77.S b/lib/cpus/aarch64/cortex_a77.S
index 0c30460..ea21999 100644
--- a/lib/cpus/aarch64/cortex_a77.S
+++ b/lib/cpus/aarch64/cortex_a77.S
@@ -22,6 +22,70 @@
#endif
/* --------------------------------------------------
+ * Errata Workaround for Cortex A77 Errata #1508412.
+ * This applies only to revision <= r1p0 of Cortex A77.
+ * Inputs:
+ * x0: variant[4:7] and revision[0:3] of current cpu.
+ * Shall clobber: x0-x17
+ * --------------------------------------------------
+ */
+func errata_a77_1508412_wa
+ /*
+ * Compare x0 against revision r1p0
+ */
+ mov x17, x30
+ bl check_errata_1508412
+ cbz x0, 3f
+ /*
+ * Compare x0 against revision r0p0
+ */
+ bl check_errata_1508412_0
+ cbz x0, 1f
+ ldr x0, =0x0
+ msr CORTEX_A77_CPUPSELR_EL3, x0
+ ldr x0, =0x00E8400000
+ msr CORTEX_A77_CPUPOR_EL3, x0
+ ldr x0, =0x00FFE00000
+ msr CORTEX_A77_CPUPMR_EL3, x0
+ ldr x0, =0x4004003FF
+ msr CORTEX_A77_CPUPCR_EL3, x0
+ ldr x0, =0x1
+ msr CORTEX_A77_CPUPSELR_EL3, x0
+ ldr x0, =0x00E8C00040
+ msr CORTEX_A77_CPUPOR_EL3, x0
+ ldr x0, =0x00FFE00040
+ msr CORTEX_A77_CPUPMR_EL3, x0
+ b 2f
+1:
+ ldr x0, =0x0
+ msr CORTEX_A77_CPUPSELR_EL3, x0
+ ldr x0, =0x00E8400000
+ msr CORTEX_A77_CPUPOR_EL3, x0
+ ldr x0, =0x00FF600000
+ msr CORTEX_A77_CPUPMR_EL3, x0
+ ldr x0, =0x00E8E00080
+ msr CORTEX_A77_CPUPOR2_EL3, x0
+ ldr x0, =0x00FFE000C0
+ msr CORTEX_A77_CPUPMR2_EL3, x0
+2:
+ ldr x0, =0x04004003FF
+ msr CORTEX_A77_CPUPCR_EL3, x0
+ isb
+3:
+ ret x17
+endfunc errata_a77_1508412_wa
+
+func check_errata_1508412
+ mov x1, #0x10
+ b cpu_rev_var_ls
+endfunc check_errata_1508412
+
+func check_errata_1508412_0
+ mov x1, #0x0
+ b cpu_rev_var_ls
+endfunc check_errata_1508412_0
+
+ /* --------------------------------------------------
* Errata Workaround for Cortex A77 Errata #1800714.
* This applies to revision <= r1p1 of Cortex A77.
* Inputs:
@@ -60,6 +124,11 @@
bl cpu_get_rev_var
mov x18, x0
+#if ERRATA_A77_1508412
+ mov x0, x18
+ bl errata_a77_1508412_wa
+#endif
+
#if ERRATA_A77_1800714
mov x0, x18
bl errata_a77_1800714_wa
@@ -98,6 +167,7 @@
* Report all errata. The revision-variant information is passed to
* checking functions of each errata.
*/
+ report_errata ERRATA_A77_1508412, cortex_a77, 1508412
report_errata ERRATA_A77_1800714, cortex_a77, 1800714
ldp x8, x30, [sp], #16
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index 7cd8ed9..5df94cc 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -278,6 +278,10 @@
# to all revisions of Cortex A76 cpu.
ERRATA_A76_1165522 ?=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
+
# Flag to apply erratum 1800714 workaround during reset. This erratum applies
# only to revision <= r1p1 of the Cortex A77 cpu.
ERRATA_A77_1800714 ?=0
@@ -551,6 +555,10 @@
$(eval $(call assert_boolean,ERRATA_A76_1165522))
$(eval $(call add_define,ERRATA_A76_1165522))
+# Process ERRATA_A77_1508412 flag
+$(eval $(call assert_boolean,ERRATA_A77_1508412))
+$(eval $(call add_define,ERRATA_A77_1508412))
+
# Process ERRATA_A77_1800714 flag
$(eval $(call assert_boolean,ERRATA_A77_1800714))
$(eval $(call add_define,ERRATA_A77_1800714))