1/*
2 * arch/s390/kernel/head31.S
3 *
4 * Copyright (C) IBM Corp. 2005,2010
5 *
6 *   Author(s):	Hartmut Penner <hp@de.ibm.com>
7 *		Martin Schwidefsky <schwidefsky@de.ibm.com>
8 *		Rob van der Heij <rvdhei@iae.nl>
9 *		Heiko Carstens <heiko.carstens@de.ibm.com>
10 *
11 */
12
13#include <linux/init.h>
14#include <linux/linkage.h>
15#include <asm/asm-offsets.h>
16#include <asm/thread_info.h>
17#include <asm/page.h>
18
19__HEAD
20ENTRY(startup_continue)
21	basr	%r13,0			# get base
22.LPG1:
23
24	l	%r1,.Lbase_cc-.LPG1(%r13)
25	mvc	0(8,%r1),__LC_LAST_UPDATE_CLOCK
26	lctl	%c0,%c15,.Lctl-.LPG1(%r13) # load control registers
27	l	%r12,.Lparmaddr-.LPG1(%r13) # pointer to parameter area
28					# move IPL device to lowcore
29#
30# Setup stack
31#
32	l	%r15,.Linittu-.LPG1(%r13)
33	st	%r15,__LC_THREAD_INFO	# cache thread info in lowcore
34	mvc	__LC_CURRENT(4),__TI_task(%r15)
35	ahi	%r15,1<<(PAGE_SHIFT+THREAD_ORDER) # init_task_union+THREAD_SIZE
36	st	%r15,__LC_KERNEL_STACK	# set end of kernel stack
37	ahi	%r15,-96
38#
39# Save ipl parameters, clear bss memory, initialize storage key for kernel pages,
40# and create a kernel NSS if the SAVESYS= parm is defined
41#
42	l	%r14,.Lstartup_init-.LPG1(%r13)
43	basr	%r14,%r14
44	lpsw  .Lentry-.LPG1(13)		# jump to _stext in primary-space,
45					# virtual and never return ...
46	.align	8
47.Lentry:.long	0x00080000,0x80000000 + _stext
48.Lctl:	.long	0x04b50000		# cr0: various things
49	.long	0			# cr1: primary space segment table
50	.long	.Lduct			# cr2: dispatchable unit control table
51	.long	0			# cr3: instruction authorization
52	.long	0			# cr4: instruction authorization
53	.long	.Lduct			# cr5: primary-aste origin
54	.long	0			# cr6:	I/O interrupts
55	.long	0			# cr7:	secondary space segment table
56	.long	0			# cr8:	access registers translation
57	.long	0			# cr9:	tracing off
58	.long	0			# cr10: tracing off
59	.long	0			# cr11: tracing off
60	.long	0			# cr12: tracing off
61	.long	0			# cr13: home space segment table
62	.long	0xc0000000		# cr14: machine check handling off
63	.long	0			# cr15: linkage stack operations
64.Lmchunk:.long	memory_chunk
65.Lbss_bgn:  .long __bss_start
66.Lbss_end:  .long _end
67.Lparmaddr: .long PARMAREA
68.Linittu:   .long init_thread_union
69.Lstartup_init:
70	    .long startup_init
71	.align	64
72.Lduct:	.long	0,0,0,0,.Lduald,0,0,0
73	.long	0,0,0,0,0,0,0,0
74	.align	128
75.Lduald:.rept	8
76	.long	0x80000000,0,0,0	# invalid access-list entries
77	.endr
78.Lbase_cc:
79	.long	sched_clock_base_cc
80
81ENTRY(_ehead)
82
83#ifdef CONFIG_SHARED_KERNEL
84	.org	0x100000 - 0x11000	# head.o ends at 0x11000
85#endif
86
87#
88# startup-code, running in absolute addressing mode
89#
90ENTRY(_stext)
91	basr	%r13,0			# get base
92.LPG3:
93# check control registers
94	stctl	%c0,%c15,0(%r15)
95	oi	2(%r15),0x60		# enable sigp emergency & external call
96	oi	0(%r15),0x10		# switch on low address protection
97	lctl	%c0,%c15,0(%r15)
98
99#
100	lam	0,15,.Laregs-.LPG3(%r13) # load access regs needed by uaccess
101	l	%r14,.Lstart-.LPG3(%r13)
102	basr	%r14,%r14		# call start_kernel
103#
104# We returned from start_kernel ?!? PANIK
105#
106	basr	%r13,0
107	lpsw	.Ldw-.(%r13)		# load disabled wait psw
108#
109	.align	8
110.Ldw:	.long	0x000a0000,0x00000000
111.Lstart:.long	start_kernel
112.Laregs:.long	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
113