fix(cpus): workaround for Cortex-X4 erratum 3076789
Cortex-X4 erratum 3076789 is a Cat B erratum that is present
in revisions r0p0, r0p1 and is fixed in r0p2.
The workaround is to set chicken bits CPUACTLR3_EL1[14:13]=0b11
and CPUACTLR_EL1[52] = 1.
Expected performance degradation is < 0.5%, but isolated
benchmark components might see higher impact.
SDEN documentation:
https://developer.arm.com/documentation/SDEN2432808/latest
Change-Id: Ib100bfab91efdb6330fdcdac127bcc5732d59196
Signed-off-by: Ryan Everett <ryan.everett@arm.com>
diff --git a/docs/design/cpu-specific-build-macros.rst b/docs/design/cpu-specific-build-macros.rst
index 5230cdc..fda43dc 100644
--- a/docs/design/cpu-specific-build-macros.rst
+++ b/docs/design/cpu-specific-build-macros.rst
@@ -843,6 +843,9 @@
- ``ERRATA_X4_2897503``: This applies errata 2897503 workaround to Cortex-X4
CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
+- ``ERRATA_X4_3076789``: This applies errata 3076789 workaround to Cortex-X4
+ CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
+
For Cortex-A510, the following errata build flags are defined :
- ``ERRATA_A510_1922240``: This applies errata 1922240 workaround to