xref: /openbmc/linux/arch/s390/kernel/head64.S (revision a2cce7a9)
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	larl	%r1,sched_clock_base_cc
20	mvc	0(8,%r1),__LC_LAST_UPDATE_CLOCK
21	larl	%r13,.LPG1		# get base
22	lctlg	%c0,%c15,.Lctl-.LPG1(%r13)	# load control registers
23	lg	%r12,.Lparmaddr-.LPG1(%r13)	# pointer to parameter area
24					# move IPL device to lowcore
25	lghi	%r0,__LC_PASTE
26	stg	%r0,__LC_VDSO_PER_CPU
27#
28# Setup stack
29#
30	larl	%r15,init_thread_union
31	stg	%r15,__LC_THREAD_INFO	# cache thread info in lowcore
32	lg	%r14,__TI_task(%r15)	# cache current in lowcore
33	stg	%r14,__LC_CURRENT
34	aghi	%r15,1<<(PAGE_SHIFT+THREAD_ORDER) # init_task_union + THREAD_SIZE
35	stg	%r15,__LC_KERNEL_STACK	# set end of kernel stack
36	aghi	%r15,-160
37#
38# Save ipl parameters, clear bss memory, initialize storage key for kernel pages,
39# and create a kernel NSS if the SAVESYS= parm is defined
40#
41	brasl	%r14,startup_init
42	lpswe	.Lentry-.LPG1(13)	# jump to _stext in primary-space,
43					# virtual and never return ...
44	.align	16
45.LPG1:
46.Lentry:.quad	0x0000000180000000,_stext
47.Lctl:	.quad	0x04040000		# cr0: AFP registers & secondary space
48	.quad	0			# cr1: primary space segment table
49	.quad	.Lduct			# cr2: dispatchable unit control table
50	.quad	0			# cr3: instruction authorization
51	.quad	0			# cr4: instruction authorization
52	.quad	.Lduct			# cr5: primary-aste origin
53	.quad	0			# cr6:	I/O interrupts
54	.quad	0			# cr7:	secondary space segment table
55	.quad	0			# cr8:	access registers translation
56	.quad	0			# cr9:	tracing off
57	.quad	0			# cr10: tracing off
58	.quad	0			# cr11: tracing off
59	.quad	0			# cr12: tracing off
60	.quad	0			# cr13: home space segment table
61	.quad	0xc0000000		# cr14: machine check handling off
62	.quad	.Llinkage_stack		# cr15: linkage stack operations
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.Lduct: .long	0,.Laste,.Laste,0,.Lduald,0,0,0
71	.long	0,0,0,0,0,0,0,0
72.Laste:	.quad	0,0xffffffffffffffff,0,0,0,0,0,0
73	.align	128
74.Lduald:.rept	8
75	.long	0x80000000,0,0,0	# invalid access-list entries
76	.endr
77.Llinkage_stack:
78	.long	0,0,0x89000000,0,0,0,0x8a000000,0
79
80ENTRY(_ehead)
81
82	.org	0x100000 - 0x11000	# head.o ends at 0x11000
83#
84# startup-code, running in absolute addressing mode
85#
86ENTRY(_stext)
87	basr	%r13,0			# get base
88.LPG3:
89# check control registers
90	stctg	%c0,%c15,0(%r15)
91	oi	6(%r15),0x60		# enable sigp emergency & external call
92	oi	4(%r15),0x10		# switch on low address proctection
93	lctlg	%c0,%c15,0(%r15)
94
95	lam	0,15,.Laregs-.LPG3(%r13)	# load acrs needed by uaccess
96	brasl	%r14,start_kernel	# go to C code
97#
98# We returned from start_kernel ?!? PANIK
99#
100	basr	%r13,0
101	lpswe	.Ldw-.(%r13)		# load disabled wait psw
102
103	.align	8
104.Ldw:	.quad	0x0002000180000000,0x0000000000000000
105.Laregs:.long	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
106