[PATCH 1/1] Added arm64 assembly for examples/api crt0

[Brunham, Kalen]

Adding Tom Rini. 

Any update from others?

-----Original Message-----
From: Brunham, Kalen <kalen.brunham at intel.com> 
Sent: Friday, May 17, 2024 3:14 PM
To: U-Boot at lists.denx.de
Subject: [PATCH 1/1] Added arm64 assembly for examples/api crt0

I've encountered a problem when compiling the 'examples/api' directory for ARM64 in U-boot. The problem lies in the assembly code in 'examples/api/crt0.S' where the current CONFIG_ARM code is only 32-bit. When targeting ARM64, a 64-bit version is necessary.

I have proposed a fix by including a 'CONFIG_ARM64' section in the assembly code as shown below.  These changes have been check via https://github.com/u-boot/u-boot/pull/538.

Feedback is welcome.

---
examples/api/crt0.S | 15 +++++++++++++++
1 file changed, 15 insertions(+)

diff --git a/examples/api/crt0.S b/examples/api/crt0.S index 57bba9d851..4c23a54b21 100644
--- a/examples/api/crt0.S
+++ b/examples/api/crt0.S
@@ -24,6 +24,21 @@ syscall:
                mtctr     %r11
                bctr

+#elif defined(CONFIG_ARM64)
+
+              .text
+              .globl _start
+_start:
+              ldr           ip0, =search_hint
+              str           sp_el2, [ip0]
+              b             main
+
+
+              .globl syscall
+syscall:
+              ldr           ip0, =syscall_ptr
+              ldr           pc_el2, [ip0]
+
#elif defined(CONFIG_ARM)

               .text
--

Signed-off-by: Kalen Brunham <kalen.brunham at intel.com>