Cortex-A72: Implement workaround for erratum 859971

Erratum 855971 applies to revision r0p3 or earlier Cortex-A72 CPUs. The
recommended workaround is to disable instruction prefetch.

Change-Id: I7fde74ee2a8a23b2a8a1891b260f0eb909fad4bf
Signed-off-by: Eleanor Bonnici <Eleanor.bonnici@arm.com>
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
diff --git a/docs/cpu-specific-build-macros.rst b/docs/cpu-specific-build-macros.rst
index 6b154f0..f74b459 100644
--- a/docs/cpu-specific-build-macros.rst
+++ b/docs/cpu-specific-build-macros.rst
@@ -21,6 +21,7 @@
 
 -  `Cortex-A53 MPCore Software Developers Errata Notice`_
 -  `Cortex-A57 MPCore Software Developers Errata Notice`_
+-  `Cortex-A72 MPCore Software Developers Errata Notice`_
 
 The errata workarounds are implemented for a particular revision or a set of
 processor revisions. This is checked by the reset handler at runtime. Each
@@ -102,6 +103,12 @@
 -  ``ERRATA_A57_859972``: This applies errata 859972 workaround to Cortex-A57
    CPU. This needs to be enabled only for revision <= r1p3 of the CPU.
 
+
+For Cortex-A72, following errata build flags are defined :
+
+-  ``ERRATA_A72_859971``: This applies errata 859971 workaround to Cortex-A72
+   CPU. This needs to be enabled only for revision <= r0p3 of the CPU.
+
 CPU Specific optimizations
 --------------------------
 
@@ -137,5 +144,6 @@
 
 .. _Cortex-A53 MPCore Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm048406/Cortex_A53_MPCore_Software_Developers_Errata_Notice.pdf
 .. _Cortex-A57 MPCore Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm049219/cortex_a57_mpcore_software_developers_errata_notice.pdf
+.. _Cortex-A72 MPCore Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm012079/index.html
 .. _Firmware Design guide: firmware-design.rst
 .. _Cortex-A57 Software Optimization Guide: http://infocenter.arm.com/help/topic/com.arm.doc.uan0015b/Cortex_A57_Software_Optimization_Guide_external.pdf