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From 26f9b5354c2de9cc052531096ff92b04c3a3846f Mon Sep 17 00:00:00 2001
From: Jaxson Han <jaxson.han@arm.com>
Date: Tue, 25 May 2021 07:25:00 +0100
Subject: [PATCH] aarch64: Prepare for EL1 booting
When booting from EL1, add a check and skip the init of
sctlr_el2 in jump_kernel
Upstream-Status: Pending
Signed-off-by: Jaxson Han <jaxson.han@arm.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
---
arch/aarch64/boot.S | 6 +++++-
arch/aarch64/include/asm/cpu.h | 1 +
2 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/arch/aarch64/boot.S b/arch/aarch64/boot.S
index 84e1646..b589744 100644
--- a/arch/aarch64/boot.S
+++ b/arch/aarch64/boot.S
@@ -156,10 +156,14 @@ ASM_FUNC(jump_kernel)
ldr x0, =SCTLR_EL1_KERNEL
msr sctlr_el1, x0
+ mrs x0, CurrentEL
+ cmp x0, #CURRENTEL_EL2
+ b.lt 1f
+
ldr x0, =SCTLR_EL2_KERNEL
msr sctlr_el2, x0
- cpuid x0, x1
+1: cpuid x0, x1
bl find_logical_id
bl setup_stack // Reset stack pointer
diff --git a/arch/aarch64/include/asm/cpu.h b/arch/aarch64/include/asm/cpu.h
index 63eb1c3..b1003f4 100644
--- a/arch/aarch64/include/asm/cpu.h
+++ b/arch/aarch64/include/asm/cpu.h
@@ -11,6 +11,7 @@
#define MPIDR_ID_BITS 0xff00ffffff
+#define CURRENTEL_EL2 (2 << 2)
#define CURRENTEL_EL3 (3 << 2)
/*
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