xref: /kvm-unit-tests/s390x/snippets/c/cstart.S (revision a6c15401b2a7d3105e5c5e6ec4e5f44dc0b73fea)
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Start assembly for snippets
4 *
5 * Copyright (c) 2021 IBM Corp.
6 *
7 * Authors:
8 *  Janosch Frank <frankja@linux.ibm.com>
9 */
10#include <asm/sigp.h>
11
12.section .init
13	.globl start
14start:
15	/* XOR all registers with themselves to clear them fully. */
16	.irp i, 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15
17	xgr \i,\i
18	.endr
19	/* 0x3000 is the stack page for now */
20	lghi	%r15, stackptr
21	sam64
22	brasl	%r14, main
23	/* For now let's only use cpu 0 in snippets so this will always work. */
24	xgr	%r0, %r0
25	sigp    %r2, %r0, SIGP_STOP
26