[boot-wrapper PATCH v3 7/8] aarch64: Prepare for booting with EL2

Jaxson Han jaxson.han at arm.com
Mon May 24 23:25:08 PDT 2021


Prepare for allowing boot-wrapper to be entered in EL2.
Detect current EL and set the corresponding EL registers.

Signed-off-by: Jaxson Han <jaxson.han at arm.com>
Reviewed-by: Andre Przywara <andre.przywara at arm.com>
---
 arch/aarch64/boot.S  |  8 ++++++++
 arch/aarch64/utils.S | 10 +++++++++-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/arch/aarch64/boot.S b/arch/aarch64/boot.S
index 5600859..14fd9cf 100644
--- a/arch/aarch64/boot.S
+++ b/arch/aarch64/boot.S
@@ -183,10 +183,18 @@ jump_kernel:
 	 */
 	bfi	x4, x19, #5, #1
 
+	mrs	x5, CurrentEL
+	cmp	x5, #CURRENTEL_EL2
+	b.eq	1f
+
 	msr	elr_el3, x19
 	msr	spsr_el3, x4
 	eret
 
+1:	msr	elr_el2, x19
+	msr	spsr_el2, x4
+	eret
+
 	.ltorg
 
 	.data
diff --git a/arch/aarch64/utils.S b/arch/aarch64/utils.S
index ae22ea7..94e9931 100644
--- a/arch/aarch64/utils.S
+++ b/arch/aarch64/utils.S
@@ -37,10 +37,18 @@ find_logical_id:
 	ret
 
 /*
- * Setup EL3 vectors
+ * Setup EL3/EL2 vectors
  * x0: vector address
  */
 setup_vector:
+	mrs	x1, CurrentEL
+	cmp	x1, #CURRENTEL_EL2
+	b.eq	1f
+
 	msr	VBAR_EL3, x0
 	isb
 	ret
+
+1:	msr	VBAR_EL2, x0
+	isb
+	ret
-- 
2.25.1




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