add aarch64 port

This adds complete aarch64 target support including bigendian subarch.

Some of the long double math functions are known to be broken otherwise
interfaces should be fully functional, but at this point consider this
port experimental.

Initial work on this port was done by Sireesh Tripurari and Kevin Bortis.

1 files changed, 27 insertions, 0 deletions

diff --git a/src/thread/aarch64/syscall_cp.s b/src/thread/aarch64/syscall_cp.s
new file mode 100644
index 00000000..6302a0bd
--- /dev/null
+++ b/src/thread/aarch64/syscall_cp.s
@@ -0,0 +1,27 @@
+// __syscall_cp_asm(&self->cancel, nr, u, v, w, x, y, z)
+//                  x0             x1  x2 x3 x4 x5 x6 x7
+
+// syscall(nr, u, v, w, x, y, z)
+//         x8  x0 x1 x2 x3 x4 x5
+
+.global __syscall_cp_asm
+.type __syscall_cp_asm,%function
+__syscall_cp_asm:
+.global __cp_begin
+__cp_begin:
+	ldr w0,[x0]
+	cbnz w0,1f
+	mov x8,x1
+	mov x0,x2
+	mov x1,x3
+	mov x2,x4
+	mov x3,x5
+	mov x4,x6
+	mov x5,x7
+	svc 0
+.global __cp_end
+__cp_end:
+	ret
+
+	// cbnz might not be able to jump far enough
+1:	b __cancel