xref: /openbmc/linux/arch/s390/kernel/head64.S (revision 23c2b932)
1/*
2 * Copyright IBM Corp. 1999, 2010
3 *
4 *   Author(s):	Hartmut Penner <hp@de.ibm.com>
5 *		Martin Schwidefsky <schwidefsky@de.ibm.com>
6 *		Rob van der Heij <rvdhei@iae.nl>
7 *		Heiko Carstens <heiko.carstens@de.ibm.com>
8 *
9 */
10
11#include <linux/init.h>
12#include <linux/linkage.h>
13#include <asm/asm-offsets.h>
14#include <asm/thread_info.h>
15#include <asm/page.h>
16
17__HEAD
18ENTRY(startup_continue)
19	tm	__LC_STFLE_FAC_LIST+5,0x80	# LPP available ?
20	jz	0f
21	xc	__LC_LPP+1(7,0),__LC_LPP+1	# clear lpp and current_pid
22	mvi	__LC_LPP,0x80			#   and set LPP_MAGIC
23	.insn	s,0xb2800000,__LC_LPP		# load program parameter
240:	larl	%r1,sched_clock_base_cc
25	mvc	0(8,%r1),__LC_LAST_UPDATE_CLOCK
26	larl	%r13,.LPG1		# get base
27	lctlg	%c0,%c15,.Lctl-.LPG1(%r13)	# load control registers
28	lg	%r12,.Lparmaddr-.LPG1(%r13)	# pointer to parameter area
29					# move IPL device to lowcore
30	lghi	%r0,__LC_PASTE
31	stg	%r0,__LC_VDSO_PER_CPU
32#
33# Setup stack
34#
35	larl	%r15,init_thread_union
36	stg	%r15,__LC_THREAD_INFO	# cache thread info in lowcore
37	lg	%r14,__TI_task(%r15)	# cache current in lowcore
38	stg	%r14,__LC_CURRENT
39	aghi	%r15,1<<(PAGE_SHIFT+THREAD_ORDER) # init_task_union + THREAD_SIZE
40	stg	%r15,__LC_KERNEL_STACK	# set end of kernel stack
41	aghi	%r15,-160
42#
43# Save ipl parameters, clear bss memory, initialize storage key for kernel pages,
44# and create a kernel NSS if the SAVESYS= parm is defined
45#
46	brasl	%r14,startup_init
47	lpswe	.Lentry-.LPG1(13)	# jump to _stext in primary-space,
48					# virtual and never return ...
49	.align	16
50.LPG1:
51.Lentry:.quad	0x0000000180000000,_stext
52.Lctl:	.quad	0x04040000		# cr0: AFP registers & secondary space
53	.quad	0			# cr1: primary space segment table
54	.quad	.Lduct			# cr2: dispatchable unit control table
55	.quad	0			# cr3: instruction authorization
56	.quad	0			# cr4: instruction authorization
57	.quad	.Lduct			# cr5: primary-aste origin
58	.quad	0			# cr6:	I/O interrupts
59	.quad	0			# cr7:	secondary space segment table
60	.quad	0			# cr8:	access registers translation
61	.quad	0			# cr9:	tracing off
62	.quad	0			# cr10: tracing off
63	.quad	0			# cr11: tracing off
64	.quad	0			# cr12: tracing off
65	.quad	0			# cr13: home space segment table
66	.quad	0xc0000000		# cr14: machine check handling off
67	.quad	.Llinkage_stack		# cr15: linkage stack operations
68.Lpcmsk:.quad	0x0000000180000000
69.L4malign:.quad 0xffffffffffc00000
70.Lscan2g:.quad	0x80000000 + 0x20000 - 8	# 2GB + 128K - 8
71.Lnop:	.long	0x07000700
72.Lparmaddr:
73	.quad	PARMAREA
74	.align	64
75.Lduct: .long	0,.Laste,.Laste,0,.Lduald,0,0,0
76	.long	0,0,0,0,0,0,0,0
77.Laste:	.quad	0,0xffffffffffffffff,0,0,0,0,0,0
78	.align	128
79.Lduald:.rept	8
80	.long	0x80000000,0,0,0	# invalid access-list entries
81	.endr
82.Llinkage_stack:
83	.long	0,0,0x89000000,0,0,0,0x8a000000,0
84
85ENTRY(_ehead)
86
87	.org	0x100000 - 0x11000	# head.o ends at 0x11000
88#
89# startup-code, running in absolute addressing mode
90#
91ENTRY(_stext)
92	basr	%r13,0			# get base
93.LPG3:
94# check control registers
95	stctg	%c0,%c15,0(%r15)
96	oi	6(%r15),0x60		# enable sigp emergency & external call
97	oi	4(%r15),0x10		# switch on low address proctection
98	lctlg	%c0,%c15,0(%r15)
99
100	lam	0,15,.Laregs-.LPG3(%r13)	# load acrs needed by uaccess
101	brasl	%r14,start_kernel	# go to C code
102#
103# We returned from start_kernel ?!? PANIK
104#
105	basr	%r13,0
106	lpswe	.Ldw-.(%r13)		# load disabled wait psw
107
108	.align	8
109.Ldw:	.quad	0x0002000180000000,0x0000000000000000
110.Laregs:.long	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
111