feat(rme): add Realm security state definition
FEAT_RME introduces two additional security states,
Root and Realm security states. This patch adds Realm
security state awareness to SMCCC helpers and entry point info
structure.
Signed-off-by: Zelalem Aweke <zelalem.aweke@arm.com>
Change-Id: I9cdefcc1aa71259b2de46e5fb62b28d658fa59bd
diff --git a/bl31/aarch64/runtime_exceptions.S b/bl31/aarch64/runtime_exceptions.S
index 51eb2bd..0d0a12d 100644
--- a/bl31/aarch64/runtime_exceptions.S
+++ b/bl31/aarch64/runtime_exceptions.S
@@ -500,6 +500,21 @@
stp x16, x17, [x6, #CTX_EL3STATE_OFFSET + CTX_SPSR_EL3]
str x18, [x6, #CTX_EL3STATE_OFFSET + CTX_SCR_EL3]
+ /* Clear flag register */
+ mov x7, xzr
+
+#if ENABLE_RME
+ /* Copy SCR_EL3.NSE bit to the flag to indicate caller's security */
+ ubfx x7, x18, #SCR_NSE_SHIFT, 1
+
+ /*
+ * Shift copied SCR_EL3.NSE bit by 5 to create space for
+ * SCR_EL3.NS bit. Bit 5 of the flag correspondes to
+ * the SCR_EL3.NSE bit.
+ */
+ lsl x7, x7, #5
+#endif /* ENABLE_RME */
+
/* Copy SCR_EL3.NS bit to the flag to indicate caller's security */
bfi x7, x18, #0, #1
diff --git a/include/common/ep_info.h b/include/common/ep_info.h
index 4bfa1fa..771572c 100644
--- a/include/common/ep_info.h
+++ b/include/common/ep_info.h
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2017-2019, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2017-2021, Arm Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@@ -18,14 +18,21 @@
#define SECURE EP_SECURE
#define NON_SECURE EP_NON_SECURE
+#define REALM EP_REALM
+#if ENABLE_RME
+#define sec_state_is_valid(s) (((s) == SECURE) || \
+ ((s) == NON_SECURE) || \
+ ((s) == REALM))
+#else
#define sec_state_is_valid(s) (((s) == SECURE) || ((s) == NON_SECURE))
+#endif
#define PARAM_EP_SECURITY_MASK EP_SECURITY_MASK
#define NON_EXECUTABLE EP_NON_EXECUTABLE
#define EXECUTABLE EP_EXECUTABLE
-/* Secure or Non-secure image */
+/* Get/set security state of an image */
#define GET_SECURITY_STATE(x) ((x) & EP_SECURITY_MASK)
#define SET_SECURITY_STATE(x, security) \
((x) = ((x) & ~EP_SECURITY_MASK) | (security))
diff --git a/include/export/common/ep_info_exp.h b/include/export/common/ep_info_exp.h
index 9d2969f..a5bd10a 100644
--- a/include/export/common/ep_info_exp.h
+++ b/include/export/common/ep_info_exp.h
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2020, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2021, Arm Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@@ -24,11 +24,23 @@
#define ENTRY_POINT_INFO_ARGS_OFFSET U(0x14)
#endif
-/* Security state of the image. */
-#define EP_SECURITY_MASK UL(0x1)
+/*
+ * Security state of the image. Bit 0 and
+ * bit 5 are used to determine the security
+ * state of the image as follows:
+ *
+ * ---------------------------------
+ * Bit 5 | Bit 0 | Security state
+ * ---------------------------------
+ * 0 0 EP_SECURE
+ * 0 1 EP_NON_SECURE
+ * 1 1 EP_REALM
+ */
+#define EP_SECURITY_MASK UL(0x21)
#define EP_SECURITY_SHIFT UL(0)
#define EP_SECURE UL(0x0)
#define EP_NON_SECURE UL(0x1)
+#define EP_REALM UL(0x21)
/* Endianness of the image. */
#define EP_EE_MASK U(0x2)
diff --git a/include/lib/smccc.h b/include/lib/smccc.h
index deaeb1d..1a39f24 100644
--- a/include/lib/smccc.h
+++ b/include/lib/smccc.h
@@ -108,9 +108,24 @@
#define SMC_ARCH_CALL_NOT_REQUIRED -2
#define SMC_ARCH_CALL_INVAL_PARAM -3
-/* Various flags passed to SMC handlers */
+/*
+ * Various flags passed to SMC handlers
+ *
+ * Bit 5 and bit 0 of the flag are used to
+ * determine the source security state as
+ * follows:
+ * ---------------------------------
+ * Bit 5 | Bit 0 | Security state
+ * ---------------------------------
+ * 0 0 SMC_FROM_SECURE
+ * 0 1 SMC_FROM_NON_SECURE
+ * 1 1 SMC_FROM_REALM
+ */
+
#define SMC_FROM_SECURE (U(0) << 0)
#define SMC_FROM_NON_SECURE (U(1) << 0)
+#define SMC_FROM_REALM U(0x21)
+#define SMC_FROM_MASK U(0x21)
#ifndef __ASSEMBLER__
@@ -118,8 +133,18 @@
#include <lib/cassert.h>
+#if ENABLE_RME
+#define is_caller_non_secure(_f) (((_f) & SMC_FROM_MASK) \
+ == SMC_FROM_NON_SECURE)
+#define is_caller_secure(_f) (((_f) & SMC_FROM_MASK) \
+ == SMC_FROM_SECURE)
+#define is_caller_realm(_f) (((_f) & SMC_FROM_MASK) \
+ == SMC_FROM_REALM)
+#define caller_sec_state(_f) ((_f) & SMC_FROM_MASK)
+#else /* ENABLE_RME */
#define is_caller_non_secure(_f) (((_f) & SMC_FROM_NON_SECURE) != U(0))
#define is_caller_secure(_f) (!is_caller_non_secure(_f))
+#endif /* ENABLE_RME */
/* The macro below is used to identify a Standard Service SMC call */
#define is_std_svc_call(_fid) (GET_SMC_OEN(_fid) == OEN_STD_START)