[U-Boot] [PATCH] imx: add lowlevel init for ARM64

[Peng Fan]

Sometimes we met SERROR, but only to catch it when Linux boots up.
Let's enable catching in U-Boot to catch it ealier and ease debug.

Signed-off-by: Peng Fan <peng.fan at nxp.com>
---
 arch/arm/mach-imx/Makefile   |  2 +-
 arch/arm/mach-imx/lowlevel.S | 22 ++++++++++++++++++++++
 2 files changed, 23 insertions(+), 1 deletion(-)
 create mode 100644 arch/arm/mach-imx/lowlevel.S

diff --git a/arch/arm/mach-imx/Makefile b/arch/arm/mach-imx/Makefile
index c3ed62aed6..37675d0558 100644
--- a/arch/arm/mach-imx/Makefile
+++ b/arch/arm/mach-imx/Makefile
@@ -204,7 +204,7 @@ endif
 
 targets += $(addprefix ../../../,SPL spl/u-boot-spl.cfgout u-boot-dtb.cfgout u-boot.cfgout u-boot.uim spl/u-boot-nand-spl.imx)
 
-obj-$(CONFIG_ARM64) += sip.o
+obj-$(CONFIG_ARM64) += lowlevel.o sip.o
 
 obj-$(CONFIG_MX5) += mx5/
 obj-$(CONFIG_MX6) += mx6/
diff --git a/arch/arm/mach-imx/lowlevel.S b/arch/arm/mach-imx/lowlevel.S
new file mode 100644
index 0000000000..158fdb7d87
--- /dev/null
+++ b/arch/arm/mach-imx/lowlevel.S
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2019 NXP
+ */
+
+#include <linux/linkage.h>
+
+ENTRY(lowlevel_init)
+	mrs	x0, CurrentEL
+	cmp	x0, #8
+	b.eq	1f
+	ret
+1:
+	msr daifclr, #4
+
+	/* set HCR_EL2.AMO to catch SERROR */
+	mrs	x0, hcr_el2
+	orr	x0, x0, #0x20
+	msr	hcr_el2, x0
+	isb
+	ret
+ENDPROC(lowlevel_init)
-- 
2.16.4