aboutsummaryrefslogtreecommitdiffstats
path: root/arch/s390/kernel/head64.S
blob: b8fec4e5c5d4ac3bd5e8da5b527901445ee78542 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
/*
 * arch/s390/kernel/head64.S
 *
 * Copyright (C) IBM Corp. 1999,2006
 *
 *   Author(s):	Hartmut Penner <hp@de.ibm.com>
 *		Martin Schwidefsky <schwidefsky@de.ibm.com>
 *		Rob van der Heij <rvdhei@iae.nl>
 *		Heiko Carstens <heiko.carstens@de.ibm.com>
 *
 */

#
# startup-code at 0x10000, running in absolute addressing mode
# this is called either by the ipl loader or directly by PSW restart
# or linload or SALIPL
#
	.org	0x10000
startup:basr	%r13,0			# get base
.LPG0:	l	%r13,0f-.LPG0(%r13)
	b	0(%r13)
0:	.long	startup_continue

#
# params at 10400 (setup.h)
#
	.org	PARMAREA
	.quad	0			# IPL_DEVICE
	.quad	0			# INITRD_START
	.quad	0			# INITRD_SIZE

	.org	COMMAND_LINE
	.byte	"root=/dev/ram0 ro"
	.byte	0

	.org	0x11000

startup_continue:
	basr	%r13,0			# get base
.LPG1:	sll	%r13,1			# remove high order bit
	srl	%r13,1
	lhi	%r1,1			# mode 1 = esame
	mvi	__LC_AR_MODE_ID,1	# set esame flag
	slr	%r0,%r0 		# set cpuid to zero
	sigp	%r1,%r0,0x12		# switch to esame mode
	sam64				# switch to 64 bit mode
	lctlg	%c0,%c15,.Lctl-.LPG1(%r13)	# load control registers
	lg	%r12,.Lparmaddr-.LPG1(%r13)	# pointer to parameter area
					# move IPL device to lowcore
	mvc	__LC_IPLDEV(4),IPL_DEVICE+4-PARMAREA(%r12)
#
# Setup stack
#
	larl	%r15,init_thread_union
	lg	%r14,__TI_task(%r15)	# cache current in lowcore
	stg	%r14,__LC_CURRENT
	aghi	%r15,1<<(PAGE_SHIFT+THREAD_ORDER) # init_task_union + THREAD_SIZE
	stg	%r15,__LC_KERNEL_STACK	# set end of kernel stack
	aghi	%r15,-160
	xc	__SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) # clear backchain
#
# Save ipl parameters, clear bss memory, initialize storage key for kernel pages,
# and create a kernel NSS if the SAVESYS= parm is defined
#
	brasl	%r14,startup_init
					# set program check new psw mask
	mvc	__LC_PGM_NEW_PSW(8),.Lpcmsk-.LPG1(%r13)
	larl	%r12,machine_flags
#
# find out if we have the MVPG instruction
#
	la	%r1,0f-.LPG1(%r13)	# set program check address
	stg	%r1,__LC_PGM_NEW_PSW+8
	sgr	%r0,%r0
	lghi	%r1,0
	lghi	%r2,0
	mvpg	%r1,%r2 		# test MVPG instruction
	oi	7(%r12),16		# set MVPG flag
0:

#
# find out if the diag 0x44 works in 64 bit mode
#
	la	%r1,0f-.LPG1(%r13)	# set program check address
	stg	%r1,__LC_PGM_NEW_PSW+8
	diag	0,0,0x44		# test diag 0x44
	oi	7(%r12),32		# set diag44 flag
0:

#
# find out if we have the IDTE instruction
#
	la	%r1,0f-.LPG1(%r13)	# set program check address
	stg	%r1,__LC_PGM_NEW_PSW+8
	.long	0xb2b10000		# store facility list
	tm	0xc8,0x08		# check bit for clearing-by-ASCE
	bno	0f-.LPG1(%r13)
	lhi	%r1,2094
	lhi	%r2,0
	.long	0xb98e2001
	oi	7(%r12),0x80		# set IDTE flag
0:

#
# find out if the diag 0x9c is available
#
	la	%r1,0f-.LPG1(%r13)	# set program check address
	stg	%r1,__LC_PGM_NEW_PSW+8
	stap	__LC_CPUID+4		# store cpu address
	lh	%r1,__LC_CPUID+4
	diag	%r1,0,0x9c		# test diag 0x9c
	oi	6(%r12),1		# set diag9c flag
0:

#
# find out if we have the MVCOS instruction
#
	la	%r1,0f-.LPG1(%r13)	# set program check address
	stg	%r1,__LC_PGM_NEW_PSW+8
	.short	0xc800			# mvcos 0(%r0),0(%r0),%r0
	.short	0x0000
	.short	0x0000
0:	tm	0x8f,0x13		# special-operation exception?
	bno	1f-.LPG1(%r13)		# if yes, MVCOS is present
	oi	6(%r12),2		# set MVCOS flag
1:

	lpswe	.Lentry-.LPG1(13)	# jump to _stext in primary-space,
					# virtual and never return ...
	.align	16
.Lentry:.quad	0x0000000180000000,_stext
.Lctl:	.quad	0x04b50002		# cr0: various things
	.quad	0			# cr1: primary space segment table
	.quad	.Lduct			# cr2: dispatchable unit control table
	.quad	0			# cr3: instruction authorization
	.quad	0			# cr4: instruction authorization
	.quad	0xffffffffffffffff	# cr5: primary-aste origin
	.quad	0			# cr6:	I/O interrupts
	.quad	0			# cr7:	secondary space segment table
	.quad	0			# cr8:	access registers translation
	.quad	0			# cr9:	tracing off
	.quad	0			# cr10: tracing off
	.quad	0			# cr11: tracing off
	.quad	0			# cr12: tracing off
	.quad	0			# cr13: home space segment table
	.quad	0xc0000000		# cr14: machine check handling off
	.quad	0			# cr15: linkage stack operations
.Lduct: .long	0,0,0,0,0,0,0,0
	.long	0,0,0,0,0,0,0,0
.Lpcmsk:.quad	0x0000000180000000
.L4malign:.quad 0xffffffffffc00000
.Lscan2g:.quad	0x80000000 + 0x20000 - 8	# 2GB + 128K - 8
.Lnop:	.long	0x07000700
.Lparmaddr:
	.quad	PARMAREA

	.globl	ipl_schib
ipl_schib:
	.rept 13
	.long 0
	.endr

	.globl	ipl_flags
ipl_flags:
	.long	0
	.globl	ipl_devno
ipl_devno:
	.word 0

	.org	0x12000

#ifdef CONFIG_SHARED_KERNEL
	.org	0x100000
#endif

#
# startup-code, running in absolute addressing mode
#
	.globl	_stext
_stext:	basr	%r13,0			# get base
.LPG3:
# check control registers
	stctg	%c0,%c15,0(%r15)
	oi	6(%r15),0x40		# enable sigp emergency signal
	oi	4(%r15),0x10		# switch on low address proctection
	lctlg	%c0,%c15,0(%r15)

	lam	0,15,.Laregs-.LPG3(%r13)	# load acrs needed by uaccess
	brasl	%r14,start_kernel	# go to C code
#
# We returned from start_kernel ?!? PANIK
#
	basr	%r13,0
	lpswe	.Ldw-.(%r13)		# load disabled wait psw

	.align	8
.Ldw:	.quad	0x0002000180000000,0x0000000000000000
.Laregs:.long	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0