1 files changed, 17 insertions, 0 deletions
diff --git a/tb/sim/syscall.S b/tb/sim/syscall.S
new file mode 100644
index 0000000..a1f7422
--- /dev/null
+++ b/tb/sim/syscall.S
@@ -0,0 +1,17 @@
+.global reset
+reset:
+	# Switch to user mode
+	mov  r0, lr
+	mrs  r1, cpsr
+	bic  r1, r1, #0b1111
+	msr  cpsr_fxc, r1
+	mov  lr, r0
+
+	mov  r0, #123
+	swi  #0
+	mov  pc, lr
+
+.global swi
+swi:
+	add  r0, r0, #1
+	movs pc, r14