fix(errata): workaround for Cortex-X2 erratum 2216384
Cortex-X2 erratum 2216384 is a Cat B erratum that applies to
revisions r0p0, r1p0 and r2p0 of CPU. It is fixed in r2p1.
The workaround is to set CPUACTLR5_EL1[17] to 1'b1 followed by
applying an instruction patching sequence.
SDEN can be found here:
https://developer.arm.com/documentation/SDEN1775100/latest
Signed-off-by: Bipin Ravi <bipin.ravi@arm.com>
Change-Id: I3c216161678887c06a28c59644e784e0c7d37bab
diff --git a/docs/design/cpu-specific-build-macros.rst b/docs/design/cpu-specific-build-macros.rst
index 54b7bac..244abf0 100644
--- a/docs/design/cpu-specific-build-macros.rst
+++ b/docs/design/cpu-specific-build-macros.rst
@@ -462,6 +462,10 @@
Cortex-X2 CPU. This needs to be enabled only for revisions r0p0, r1p0 and
r2p0 of the CPU, it is fixed in r2p1.
+- ``ERRATA_X2_2216384``: This applies errata 2216384 workaround to
+ Cortex-X2 CPU. This needs to be enabled only for revisions r0p0, r1p0 and
+ r2p0 of the CPU, it is fixed in r2p1.
+
DSU Errata Workarounds
----------------------
diff --git a/include/lib/cpus/aarch64/cortex_x2.h b/include/lib/cpus/aarch64/cortex_x2.h
index e1695cd..e3d0fa9 100644
--- a/include/lib/cpus/aarch64/cortex_x2.h
+++ b/include/lib/cpus/aarch64/cortex_x2.h
@@ -34,6 +34,7 @@
* CPU Auxiliary Control Register 5 definitions
******************************************************************************/
#define CORTEX_X2_CPUACTLR5_EL1 S3_0_C15_C8_0
+#define CORTEX_X2_CPUACTLR5_EL1_BIT_17 (ULL(1) << 17)
/*******************************************************************************
* CPU Implementation Specific Selected Instruction registers
diff --git a/lib/cpus/aarch64/cortex_x2.S b/lib/cpus/aarch64/cortex_x2.S
index 155ae5e..2ecfbbb 100644
--- a/lib/cpus/aarch64/cortex_x2.S
+++ b/lib/cpus/aarch64/cortex_x2.S
@@ -184,6 +184,44 @@
b cpu_rev_var_ls
endfunc check_errata_2081180
+ /* --------------------------------------------------
+ * Errata Workaround for Cortex X2 Errata 2216384.
+ * This applies to revisions r0p0, r1p0, and r2p0
+ * and is fixed in r2p1.
+ * x0: variant[4:7] and revision[0:3] of current cpu.
+ * Shall clobber: x0, x1, x17
+ * --------------------------------------------------
+ */
+func errata_x2_2216384_wa
+ /* Check workaround compatibility. */
+ mov x17, x30
+ bl check_errata_2216384
+ cbz x0, 1f
+
+ mrs x1, CORTEX_X2_CPUACTLR5_EL1
+ orr x1, x1, CORTEX_X2_CPUACTLR5_EL1_BIT_17
+ msr CORTEX_X2_CPUACTLR5_EL1, x1
+
+ /* Apply instruction patching sequence */
+ ldr x0, =0x5
+ msr CORTEX_X2_IMP_CPUPSELR_EL3, x0
+ ldr x0, =0x10F600E000
+ msr CORTEX_X2_IMP_CPUPOR_EL3, x0
+ ldr x0, =0x10FF80E000
+ msr CORTEX_X2_IMP_CPUPMR_EL3, x0
+ ldr x0, =0x80000000003FF
+ msr CORTEX_X2_IMP_CPUPCR_EL3, x0
+ isb
+
+1:
+ ret x17
+endfunc errata_x2_2216384_wa
+
+func check_errata_2216384
+ /* Applies to r0p0 - r2p0 */
+ mov x1, #0x20
+ b cpu_rev_var_ls
+endfunc check_errata_2216384
/* ----------------------------------------------------
* HW will do the cache maintenance while powering down
* ----------------------------------------------------
@@ -219,6 +257,7 @@
report_errata ERRATA_X2_2083908, cortex_x2, 2083908
report_errata ERRATA_X2_2017096, cortex_x2, 2017096
report_errata ERRATA_X2_2081180, cortex_x2, 2081180
+ report_errata ERRATA_X2_2216384, cortex_x2, 2216384
ldp x8, x30, [sp], #16
ret
@@ -261,6 +300,11 @@
bl errata_x2_2081180_wa
#endif
+#if ERRATA_X2_2216384
+ mov x0, x18
+ bl errata_x2_2216384_wa
+#endif
+
ret x19
endfunc cortex_x2_reset_func
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index feb895d..f1c4c90 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -517,6 +517,11 @@
# r2p1.
ERRATA_X2_2081180 ?=0
+# Flag to apply erratum 2216384 workaround during reset. This erratum applies
+# only to revisions r0p0, r1p0 and r2p0 of the Cortex-X2 cpu, it is fixed in
+# r2p1.
+ERRATA_X2_2216384 ?=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
@@ -962,6 +967,10 @@
$(eval $(call assert_boolean,ERRATA_X2_2081180))
$(eval $(call add_define,ERRATA_X2_2081180))
+# Process ERRATA_X2_2216384 flag
+$(eval $(call assert_boolean,ERRATA_X2_2216384))
+$(eval $(call add_define,ERRATA_X2_2216384))
+
# Process ERRATA_DSU_798953 flag
$(eval $(call assert_boolean,ERRATA_DSU_798953))
$(eval $(call add_define,ERRATA_DSU_798953))