refactor(cpufeat): enable FEAT_ECV for FEAT_STATE_CHECKED
At the moment we only support FEAT_ECV to be either unconditionally
compiled in, or to be not supported at all.
Add support for runtime detection (ENABLE_FEAT_ECV=2), by splitting
is_feat_ecv_present() into an ID register reading function and a second
function to report the support status. That function considers both
build time settings and runtime information (if needed), and is used
before we access the CNTPOFF_EL2 system register.
Also move the context saving code from assembly to C, and use the new
is_feat_ecv_supported() function to guard its execution.
Change the FVP platform default to the now supported dynamic option (=2),
so the right decision can be made by the code at runtime.
Change-Id: I4acd5384929f1902b62a87ae073aafa1472cd66b
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
diff --git a/plat/arm/board/fvp/platform.mk b/plat/arm/board/fvp/platform.mk
index 3f18112..683234f 100644
--- a/plat/arm/board/fvp/platform.mk
+++ b/plat/arm/board/fvp/platform.mk
@@ -470,6 +470,7 @@
ENABLE_FEAT_HCX := 2
ENABLE_FEAT_TCR2 := 2
+ENABLE_FEAT_ECV := 2
ENABLE_FEAT_PAN := 2
ENABLE_FEAT_VHE := 2
ENABLE_MPAM_FOR_LOWER_ELS := 2