commit cb4ec47b5c73e04472984acf821e6be41b98064f
author johpow01 <john.powell@arm.com> Wed Aug 04 19:38:18 2021 -0500
committer John <john.powell@arm.com> Mon Sep 27 17:07:52 2021 +0200
tree 2489a386867098d385fdf263dc8cc1bcd2f98a4a
parent c7c22ab662008ca6cfb8b1926bbaa5fdc8eb399e

feat(hcx): add build option to enable FEAT_HCX

FEAT_HCX adds the extended hypervisor configuration register (HCRX_EL2)
and access to this register must be explicitly enabled through the
SCR_EL3.HXEn bit.  This patch adds a new build flag ENABLE_FEAT_HCX to
allow the register to be accessed from EL2.

Signed-off-by: John Powell <john.powell@arm.com>
Change-Id: Ibb36ad90622f1dc857adab4b0d4d7a89456a522b

lib/el3_runtime/aarch64/context.S

diff --git a/lib/el3_runtime/aarch64/context.S b/lib/el3_runtime/aarch64/context.S
index 40e7ddf..e270ad0 100644
--- a/lib/el3_runtime/aarch64/context.S
+++ b/lib/el3_runtime/aarch64/context.S
@@ -193,6 +193,11 @@
 	str	x13, [x0, #CTX_SCXTNUM_EL2]
 #endif
 
+#if ENABLE_FEAT_HCX
+	mrs	x14, hcrx_el2
+	str	x14, [x0, #CTX_HCRX_EL2]
+#endif
+
 	ret
 endfunc el2_sysregs_context_save
 
@@ -362,6 +367,11 @@
 	msr	scxtnum_el2, x13
 #endif
 
+#if ENABLE_FEAT_HCX
+	ldr	x14, [x0, #CTX_HCRX_EL2]
+	msr	hcrx_el2, x14
+#endif
+
 	ret
 endfunc el2_sysregs_context_restore