fix(errata): workaround for Cortex-A78C 2132064
Cortex-A78C erratum 2132064 is a cat B erratum that applies to revisions
r0p1 and r0p2 and is still open.
This patch implements workaround option 2 that places the data
prefetcher in the most conservative mode to greatly reduce prefetches
by writing the following bits to the value indicated:
ecltr[7:6], PF_MODE = 2'b11
SDEN can be found here:
https://developer.arm.com/documentation/SDEN2004089/latest
Signed-off-by: Lauren Wehrmeister <lauren.wehrmeister@arm.com>
Change-Id: Ica2561c1e257643c2482085447ef852fa62a1eb2
diff --git a/docs/design/cpu-specific-build-macros.rst b/docs/design/cpu-specific-build-macros.rst
index 07e7821..2e3fe74 100644
--- a/docs/design/cpu-specific-build-macros.rst
+++ b/docs/design/cpu-specific-build-macros.rst
@@ -325,6 +325,12 @@
Cortex-A78 AE CPU. This needs to be enabled for revisions r0p0 and r0p1. This
erratum is still open.
+For Cortex-A78C, the following errata build flags are defined :
+
+- ``ERRATA_A78C_2132064`` : This applies errata 2132064 workaround to
+ Cortex-A78C CPU. This needs to be enabled for revisions r0p1, r0p2 and
+ it is still open.
+
For Cortex-X1 CPU, the following errata build flags are defined:
- ``ERRATA_X1_1821534`` : This applies errata 1821534 workaround to Cortex-X1
diff --git a/include/lib/cpus/aarch64/cortex_a78c.h b/include/lib/cpus/aarch64/cortex_a78c.h
index b1945ed..39e2adf 100644
--- a/include/lib/cpus/aarch64/cortex_a78c.h
+++ b/include/lib/cpus/aarch64/cortex_a78c.h
@@ -17,6 +17,8 @@
* CPU Extended Control register specific definitions.
******************************************************************************/
#define CORTEX_A78C_CPUECTLR_EL1 S3_0_C15_C1_4
+#define CORTEX_A78C_CPUECTLR_EL1_BIT6 (ULL(1) << 6)
+#define CORTEX_A78C_CPUECTLR_EL1_BIT7 (ULL(1) << 7)
/*******************************************************************************
* CPU Power Control register specific definitions
diff --git a/lib/cpus/aarch64/cortex_a78c.S b/lib/cpus/aarch64/cortex_a78c.S
index 0712109..f57ecaf 100644
--- a/lib/cpus/aarch64/cortex_a78c.S
+++ b/lib/cpus/aarch64/cortex_a78c.S
@@ -21,6 +21,43 @@
wa_cve_2022_23960_bhb_vector_table CORTEX_A78C_BHB_LOOP_COUNT, cortex_a78c
#endif /* WORKAROUND_CVE_2022_23960 */
+/* --------------------------------------------------
+ * Errata Workaround for A78C Erratum 2132064.
+ * This applies to revisions r0p1 and r0p2 of A78C
+ * and is still open.
+ * Inputs:
+ * x0: variant[4:7] and revision[0:3] of current cpu.
+ * Shall clobber: x0-x17
+ * --------------------------------------------------
+ */
+func errata_a78c_2132064_wa
+ /* Compare x0 against revisions r0p0 - r0p1 */
+ mov x17, x30
+ bl check_errata_2132064
+ cbz x0, 1f
+
+ /* --------------------------------------------------------
+ * Place the data prefetcher in the most conservative mode
+ * to reduce prefetches by writing the following bits to
+ * the value indicated: ecltr[7:6], PF_MODE = 2'b11
+ * --------------------------------------------------------
+ */
+ mrs x0, CORTEX_A78C_CPUECTLR_EL1
+ orr x0, x0, #CORTEX_A78C_CPUECTLR_EL1_BIT6
+ orr x0, x0, #CORTEX_A78C_CPUECTLR_EL1_BIT7
+ msr CORTEX_A78C_CPUECTLR_EL1, x0
+ isb
+1:
+ ret x17
+endfunc errata_a78c_2132064_wa
+
+func check_errata_2132064
+ /* Applies to revisions r0p1 and r0p2. */
+ mov x1, #CPU_REV(0, 1)
+ mov x2, #CPU_REV(0, 2)
+ b cpu_rev_var_range
+endfunc check_errata_2132064
+
func check_errata_cve_2022_23960
#if WORKAROUND_CVE_2022_23960
mov x0, #ERRATA_APPLIES
@@ -35,6 +72,15 @@
* -------------------------------------------------
*/
func cortex_a78c_reset_func
+ mov x19, x30
+ bl cpu_get_rev_var
+ mov x18, x0
+
+#if ERRATA_A78C_2132064
+ mov x0, x18
+ bl errata_a78c_2132064_wa
+#endif
+
#if IMAGE_BL31 && WORKAROUND_CVE_2022_23960
/*
* The Cortex-A78c generic vectors are overridden to apply errata
@@ -43,8 +89,9 @@
adr x0, wa_cve_vbar_cortex_a78c
msr vbar_el3, x0
#endif /* IMAGE_BL31 && WORKAROUND_CVE_2022_23960 */
+
isb
- ret
+ ret x19
endfunc cortex_a78c_reset_func
/* ----------------------------------------------------
@@ -77,6 +124,7 @@
* Report all errata. The revision-variant information is passed to
* checking functions of each errata.
*/
+ report_errata ERRATA_A78C_2132064, cortex_a78c, 2132064
report_errata WORKAROUND_CVE_2022_23960, cortex_a78c, cve_2022_23960
ldp x8, x30, [sp], #16
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index 5eecdd6..19e611c 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -361,6 +361,10 @@
# to revisions r0p0 and r0p1 of the A78 AE cpu. It is still open.
ERRATA_A78_AE_2395408 ?=0
+# Flag to apply erratum 2132064 workaround during reset. This erratum applies
+# to revisions r0p1 and r0p2 of the A78C cpu. It is still open.
+ERRATA_A78C_2132064 ?=0
+
# Flag to apply erratum 1821534 workaround during reset. This erratum applies
# to revisions r0p0 - r1p0 of the X1 cpu and fixed in r1p1.
ERRATA_X1_1821534 ?=0
@@ -915,6 +919,10 @@
$(eval $(call assert_boolean,ERRATA_A78_AE_2395408))
$(eval $(call add_define,ERRATA_A78_AE_2395408))
+# Process ERRATA_A78C_2132064 flag
+$(eval $(call assert_boolean,ERRATA_A78C_2132064))
+$(eval $(call add_define,ERRATA_A78C_2132064))
+
# Process ERRATA_X1_1821534 flag
$(eval $(call assert_boolean,ERRATA_X1_1821534))
$(eval $(call add_define,ERRATA_X1_1821534))