xref: /openbmc/linux/arch/s390/kernel/head64.S (revision f519f0be)
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright IBM Corp. 1999, 2010
4 *
5 *   Author(s):	Hartmut Penner <hp@de.ibm.com>
6 *		Martin Schwidefsky <schwidefsky@de.ibm.com>
7 *		Rob van der Heij <rvdhei@iae.nl>
8 *		Heiko Carstens <heiko.carstens@de.ibm.com>
9 *
10 */
11
12#include <linux/init.h>
13#include <linux/linkage.h>
14#include <asm/asm-offsets.h>
15#include <asm/thread_info.h>
16#include <asm/page.h>
17#include <asm/ptrace.h>
18
19__HEAD
20ENTRY(startup_continue)
21	tm	__LC_STFLE_FAC_LIST+5,0x80	# LPP available ?
22	jz	0f
23	xc	__LC_LPP+1(7,0),__LC_LPP+1	# clear lpp and current_pid
24	mvi	__LC_LPP,0x80			#   and set LPP_MAGIC
25	.insn	s,0xb2800000,__LC_LPP		# load program parameter
260:	larl	%r1,tod_clock_base
27	mvc	0(16,%r1),__LC_BOOT_CLOCK
28	larl	%r13,.LPG1		# get base
29	larl	%r0,boot_vdso_data
30	stg	%r0,__LC_VDSO_PER_CPU
31#
32# Setup stack
33#
34	larl	%r14,init_task
35	stg	%r14,__LC_CURRENT
36	larl	%r15,init_thread_union+THREAD_SIZE-STACK_FRAME_OVERHEAD
37#
38# Early setup functions that may not rely on an initialized bss section,
39# like moving the initrd. Returns with an initialized bss section.
40#
41	brasl	%r14,startup_init_nobss
42#
43# Early machine initialization and detection functions.
44#
45	brasl	%r14,startup_init
46
47# check control registers
48	stctg	%c0,%c15,0(%r15)
49	oi	6(%r15),0x60		# enable sigp emergency & external call
50	oi	4(%r15),0x10		# switch on low address proctection
51	lctlg	%c0,%c15,0(%r15)
52
53	lam	0,15,.Laregs-.LPG1(%r13)	# load acrs needed by uaccess
54	brasl	%r14,start_kernel		# go to C code
55#
56# We returned from start_kernel ?!? PANIK
57#
58	basr	%r13,0
59	lpswe	.Ldw-.(%r13)		# load disabled wait psw
60
61	.align	16
62.LPG1:
63.Lpcmsk:.quad	0x0000000180000000
64.L4malign:.quad 0xffffffffffc00000
65.Lscan2g:.quad	0x80000000 + 0x20000 - 8	# 2GB + 128K - 8
66.Lnop:	.long	0x07000700
67.Lparmaddr:
68	.quad	PARMAREA
69	.align	64
70.Ldw:	.quad	0x0002000180000000,0x0000000000000000
71.Laregs:.long	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
72