Cortex-A55: workarounds for errata 1221012
The workaround is added to the Cortex-A55 cpu specific file. The
workaround is disabled by default and have to be explicitly enabled by
the platform integrator.
Change-Id: I3e6fd10df6444122a8ee7d08058946ff1cc912f8
Signed-off-by: Ambroise Vincent <ambroise.vincent@arm.com>
diff --git a/docs/design/cpu-specific-build-macros.rst b/docs/design/cpu-specific-build-macros.rst
index e49c73e..07983a9 100644
--- a/docs/design/cpu-specific-build-macros.rst
+++ b/docs/design/cpu-specific-build-macros.rst
@@ -143,6 +143,9 @@
- ``ERRATA_A55_903758``: This applies errata 903758 workaround to Cortex-A55
CPU. This needs to be enabled only for revision <= r0p1 of the CPU.
+- ``ERRATA_A55_1221012``: This applies errata 1221012 workaround to Cortex-A55
+ CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
+
For Cortex-A57, the following errata build flags are defined :
- ``ERRATA_A57_806969``: This applies errata 806969 workaround to Cortex-A57
diff --git a/include/lib/cpus/aarch64/cortex_a55.h b/include/lib/cpus/aarch64/cortex_a55.h
index feac1d2..60ed957 100644
--- a/include/lib/cpus/aarch64/cortex_a55.h
+++ b/include/lib/cpus/aarch64/cortex_a55.h
@@ -39,4 +39,10 @@
/* Definitions of register field mask in CORTEX_A55_CPUPWRCTLR_EL1 */
#define CORTEX_A55_CORE_PWRDN_EN_MASK U(0x1)
+/* Instruction patching registers */
+#define CPUPSELR_EL3 S3_6_C15_C8_0
+#define CPUPCR_EL3 S3_6_C15_C8_1
+#define CPUPOR_EL3 S3_6_C15_C8_2
+#define CPUPMR_EL3 S3_6_C15_C8_3
+
#endif /* CORTEX_A55_H */
diff --git a/lib/cpus/aarch64/cortex_a55.S b/lib/cpus/aarch64/cortex_a55.S
index 0ef373a..8e13824 100644
--- a/lib/cpus/aarch64/cortex_a55.S
+++ b/lib/cpus/aarch64/cortex_a55.S
@@ -175,6 +175,53 @@
b cpu_rev_var_ls
endfunc check_errata_903758
+ /* -----------------------------------------------------
+ * Errata Workaround for Cortex A55 Errata #1221012.
+ * This applies only to revisions <= r1p0 of Cortex A55.
+ * Inputs:
+ * x0: variant[4:7] and revision[0:3] of current cpu.
+ * Shall clobber: x0-x17
+ * -----------------------------------------------------
+ */
+func errata_a55_1221012_wa
+ /*
+ * Compare x0 against revision r1p0
+ */
+ mov x17, x30
+ bl check_errata_1221012
+ cbz x0, 1f
+ mov x0, #0x0020
+ movk x0, #0x0850, lsl #16
+ msr CPUPOR_EL3, x0
+ mov x0, #0x0000
+ movk x0, #0x1FF0, lsl #16
+ movk x0, #0x2, lsl #32
+ msr CPUPMR_EL3, x0
+ mov x0, #0x03fd
+ movk x0, #0x0110, lsl #16
+ msr CPUPCR_EL3, x0
+ mov x0, #0x1
+ msr CPUPSELR_EL3, x0
+ mov x0, #0x0040
+ movk x0, #0x08D0, lsl #16
+ msr CPUPOR_EL3, x0
+ mov x0, #0x0040
+ movk x0, #0x1FF0, lsl #16
+ movk x0, #0x2, lsl #32
+ msr CPUPMR_EL3, x0
+ mov x0, #0x03fd
+ movk x0, #0x0110, lsl #16
+ msr CPUPCR_EL3, x0
+ isb
+1:
+ ret x17
+endfunc errata_a55_1221012_wa
+
+func check_errata_1221012
+ mov x1, #0x10
+ b cpu_rev_var_ls
+endfunc check_errata_1221012
+
func cortex_a55_reset_func
mov x19, x30
@@ -214,6 +261,11 @@
bl errata_a55_903758_wa
#endif
+#if ERRATA_A55_1221012
+ mov x0, x18
+ bl errata_a55_1221012_wa
+#endif
+
ret x19
endfunc cortex_a55_reset_func
@@ -253,6 +305,7 @@
report_errata ERRATA_A55_798797, cortex_a55, 798797
report_errata ERRATA_A55_846532, cortex_a55, 846532
report_errata ERRATA_A55_903758, cortex_a55, 903758
+ report_errata ERRATA_A55_1221012, cortex_a55, 1221012
ldp x8, x30, [sp], #16
ret
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index e45d79d..599e11e 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -134,6 +134,10 @@
# only to revision <= r0p1 of the Cortex A55 cpu.
ERRATA_A55_903758 ?=0
+# Flag to apply erratum 1221012 workaround during reset. This erratum applies
+# only to revision <= r1p0 of the Cortex A55 cpu.
+ERRATA_A55_1221012 ?=0
+
# Flag to apply erratum 806969 workaround during reset. This erratum applies
# only to revision r0p0 of the Cortex A57 cpu.
ERRATA_A57_806969 ?=0
@@ -319,6 +323,10 @@
$(eval $(call assert_boolean,ERRATA_A55_903758))
$(eval $(call add_define,ERRATA_A55_903758))
+# Process ERRATA_A55_1221012 flag
+$(eval $(call assert_boolean,ERRATA_A55_1221012))
+$(eval $(call add_define,ERRATA_A55_1221012))
+
# Process ERRATA_A57_806969 flag
$(eval $(call assert_boolean,ERRATA_A57_806969))
$(eval $(call add_define,ERRATA_A57_806969))