Add support for enabling S-EL2
This patch adds support for enabling S-EL2 if this EL is specified in the entry
point information being used to initialise a secure context. It is the caller's
responsibility to check if S-EL2 is available on the system before requesting
this EL through the entry point information.
Signed-off-by: Achin Gupta <achin.gupta@arm.com>
Change-Id: I2752964f078ab528b2e80de71c7d2f35e60569e1
diff --git a/include/arch/aarch64/arch.h b/include/arch/aarch64/arch.h
index 3ff2912..e48e201 100644
--- a/include/arch/aarch64/arch.h
+++ b/include/arch/aarch64/arch.h
@@ -140,6 +140,8 @@
#define ID_AA64PFR0_GIC_MASK ULL(0xf)
#define ID_AA64PFR0_SVE_SHIFT U(32)
#define ID_AA64PFR0_SVE_MASK ULL(0xf)
+#define ID_AA64PFR0_SEL2_SHIFT U(36)
+#define ID_AA64PFR0_SEL2_MASK U(0xf)
#define ID_AA64PFR0_MPAM_SHIFT U(40)
#define ID_AA64PFR0_MPAM_MASK ULL(0xf)
#define ID_AA64PFR0_DIT_SHIFT U(48)
@@ -285,6 +287,7 @@
#define SCR_RES1_BITS ((U(1) << 4) | (U(1) << 5))
#define SCR_ATA_BIT (U(1) << 26)
#define SCR_FIEN_BIT (U(1) << 21)
+#define SCR_EEL2_BIT (U(1) << 18)
#define SCR_API_BIT (U(1) << 17)
#define SCR_APK_BIT (U(1) << 16)
#define SCR_TWE_BIT (U(1) << 13)
diff --git a/lib/el3_runtime/aarch64/context_mgmt.c b/lib/el3_runtime/aarch64/context_mgmt.c
index d65e02d..752a260 100644
--- a/lib/el3_runtime/aarch64/context_mgmt.c
+++ b/lib/el3_runtime/aarch64/context_mgmt.c
@@ -181,6 +181,10 @@
scr_el3 |= SCR_HCE_BIT;
}
+ /* Enable S-EL2 if the next EL is EL2 and security state is secure */
+ if ((security_state == SECURE) && (GET_EL(ep->spsr) == MODE_EL2))
+ scr_el3 |= SCR_EEL2_BIT;
+
/*
* Initialise SCTLR_EL1 to the reset value corresponding to the target
* execution state setting all fields rather than relying of the hw.