refactor(ras): replace RAS_EXTENSION with FEAT_RAS

The current usage of RAS_EXTENSION in TF-A codebase is to cater for two
things in TF-A :
1. Pull in necessary framework and platform hooks for Firmware first
   handling(FFH) of RAS errors.
2. Manage the FEAT_RAS extension when switching the worlds.

FFH means that all the EAs from NS are trapped in EL3 first and signaled
to NS world later after the first handling is done in firmware. There is
an alternate way of handling RAS errors viz Kernel First handling(KFH).
Tying FEAT_RAS to RAS_EXTENSION build flag was not correct as the
feature is needed for proper handling KFH in as well.

This patch breaks down the RAS_EXTENSION flag into a flag to denote the
CPU architecture `ENABLE_FEAT_RAS` which is used in context management
during world switch and another flag `RAS_FFH_SUPPORT` to pull in
required framework and platform hooks for FFH.

Proper support for KFH will be added in future patches.

BREAKING CHANGE: The previous RAS_EXTENSION is now deprecated. The
equivalent functionality can be achieved by the following
2 options:
 - ENABLE_FEAT_RAS
 - RAS_FFH_SUPPORT

Signed-off-by: Manish Pandey <manish.pandey2@arm.com>
Change-Id: I1abb9ab6622b8f1b15712b12f17612804d48a6ec

1 files changed, 16 insertions, 8 deletions

diff --git a/Makefile b/Makefile
index cf71c0903..d5e64ea45 100644
--- a/Makefile
+++ b/Makefile
@@ -794,17 +794,23 @@ ifeq ($(RESET_TO_BL2)-$(BL2_IN_XIP_MEM),0-1)
 $(error "BL2_IN_XIP_MEM is only supported when RESET_TO_BL2 is enabled")
 endif
 
-# For RAS_EXTENSION, require that EAs are handled in EL3 first
+# RAS_EXTENSION is deprecated, provide alternate build options
 ifeq ($(RAS_EXTENSION),1)
+    $(error "RAS_EXTENSION is now deprecated, please use ENABLE_FEAT_RAS and RAS_FFH_SUPPORT instead")
+endif
+# RAS firmware first handling requires that EAs are handled in EL3 first
+ifeq ($(RAS_FFH_SUPPORT),1)
+    ifneq ($(ENABLE_FEAT_RAS),1)
+        $(error For RAS_FFH_SUPPORT, ENABLE_FEAT_RAS must also be 1)
+    endif
     ifneq ($(HANDLE_EA_EL3_FIRST_NS),1)
-        $(error For RAS_EXTENSION, HANDLE_EA_EL3_FIRST_NS must also be 1)
+        $(error For RAS_FFH_SUPPORT, HANDLE_EA_EL3_FIRST_NS must also be 1)
     endif
 endif
-
-# When FAULT_INJECTION_SUPPORT is used, require that RAS_EXTENSION is enabled
+# When FAULT_INJECTION_SUPPORT is used, require that FEAT_RAS is enabled
 ifeq ($(FAULT_INJECTION_SUPPORT),1)
-    ifneq ($(RAS_EXTENSION),1)
-        $(error For FAULT_INJECTION_SUPPORT, RAS_EXTENSION must also be 1)
+    ifneq ($(ENABLE_FEAT_RAS),1)
+        $(error For FAULT_INJECTION_SUPPORT, ENABLE_FEAT_RAS must also be 1)
     endif
 endif
 
@@ -1169,6 +1175,7 @@ $(eval $(call assert_booleans,\
         FEATURE_DETECTION \
 	TRNG_SUPPORT \
 	CONDITIONAL_CMO \
+	RAS_FFH_SUPPORT \
 )))
 
 $(eval $(call assert_numerics,\
@@ -1187,6 +1194,7 @@ $(eval $(call assert_numerics,\
         ENABLE_FEAT_AMU \
         ENABLE_FEAT_AMUv1p1 \
         ENABLE_FEAT_CSV2_2 \
+        ENABLE_FEAT_RAS	\
         ENABLE_FEAT_DIT \
         ENABLE_FEAT_ECV \
         ENABLE_FEAT_FGT \
@@ -1213,7 +1221,6 @@ $(eval $(call assert_numerics,\
         FW_ENC_STATUS \
         NR_OF_FW_BANKS \
         NR_OF_IMAGES_IN_FW_BANK \
-        RAS_EXTENSION \
         TWED_DELAY \
         ENABLE_FEAT_TWED \
         SVE_VECTOR_LEN \
@@ -1286,7 +1293,8 @@ $(eval $(call add_defines,\
         PROGRAMMABLE_RESET_ADDRESS \
         PSCI_EXTENDED_STATE_ID \
         PSCI_OS_INIT_MODE \
-        RAS_EXTENSION \
+        ENABLE_FEAT_RAS \
+        RAS_FFH_SUPPORT \
         RESET_TO_BL31 \
         SEPARATE_CODE_AND_RODATA \
         SEPARATE_BL2_NOLOAD_REGION \