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 *
9 * There are 5 different IPL methods
10 * 1) load the image directly into ram at address 0 and do an PSW restart
11 * 2) linload will load the image from address 0x10000 to memory 0x10000
12 * and start the code thru LPSW 0x0008000080010000 (VM only, deprecated)
13 * 3) generate the tape ipl header, store the generated image on a tape
14 * and ipl from it
15 * In case of SL tape you need to IPL 5 times to get past VOL1 etc
16 * 4) generate the vm reader ipl header, move the generated image to the
17 * VM reader (use option NOH!) and do a ipl from reader (VM only)
18 * 5) direct call of start by the SALIPL loader
19 * We use the cpuid to distinguish between VM and native ipl
20 * params for kernel are pushed to 0x10400 (see setup.h)
21 *
22 */
23
24#include <linux/init.h>
25#include <linux/linkage.h>
26#include <asm/asm-offsets.h>
27#include <asm/page.h>
28#include <asm/ptrace.h>
29#include <asm/sclp.h>
30#include "boot.h"
31
32#define EP_OFFSET 0x10008
33#define EP_STRING "S390EP"
34#define IPL_BS 0x730
35
36__HEAD
37ipl_start:
38 mvi __LC_AR_MODE_ID,1 # set esame flag
39 slr %r0,%r0 # set cpuid to zero
40 lhi %r1,2 # mode 2 = esame (dump)
41 sigp %r1,%r0,0x12 # switch to esame mode
42 sam64 # switch to 64 bit addressing mode
43 lgh %r1,__LC_SUBCHANNEL_ID # test if subchannel number
44 brctg %r1,.Lnoload # is valid
45 llgf %r1,__LC_SUBCHANNEL_ID # load ipl subchannel number
46 lghi %r2,IPL_BS # load start address
47 bras %r14,.Lloader # load rest of ipl image
48 larl %r12,parmarea # pointer to parameter area
49 stg %r1,IPL_DEVICE-PARMAREA(%r12) # save ipl device number
50#
51# load parameter file from ipl device
52#
53.Lagain1:
54 larl %r2,_end # ramdisk loc. is temp
55 bras %r14,.Lloader # load parameter file
56 ltgr %r2,%r2 # got anything ?
57 jz .Lnopf
58 lg %r3,MAX_COMMAND_LINE_SIZE-PARMAREA(%r12)
59 aghi %r3,-1
60 clgr %r2,%r3
61 jl .Lnotrunc
62 lgr %r2,%r3
63.Lnotrunc:
64 larl %r4,_end
65 larl %r13,.L_hdr
66 clc 0(3,%r4),0(%r13) # if it is HDRx
67 jz .Lagain1 # skip dataset header
68 larl %r13,.L_eof
69 clc 0(3,%r4),0(%r13) # if it is EOFx
70 jz .Lagain1 # skip data set trailer
71 lgr %r5,%r2
72 la %r6,COMMAND_LINE-PARMAREA(%r12)
73 lgr %r7,%r2
74 aghi %r7,1
75 mvcl %r6,%r4
76.Lnopf:
77#
78# load ramdisk from ipl device
79#
80.Lagain2:
81 larl %r2,_end # addr of ramdisk
82 stg %r2,INITRD_START-PARMAREA(%r12)
83 bras %r14,.Lloader # load ramdisk
84 stg %r2,INITRD_SIZE-PARMAREA(%r12) # store size of rd
85 ltgr %r2,%r2
86 jnz .Lrdcont
87 stg %r2,INITRD_START-PARMAREA(%r12) # no ramdisk found
88.Lrdcont:
89 larl %r2,_end
90 larl %r13,.L_hdr # skip HDRx and EOFx
91 clc 0(3,%r2),0(%r13)
92 jz .Lagain2
93 larl %r13,.L_eof
94 clc 0(3,%r2),0(%r13)
95 jz .Lagain2
96#
97# reset files in VM reader
98#
99 larl %r13,.Lcpuid
100 stidp 0(%r13) # store cpuid
101 tm 0(%r13),0xff # running VM ?
102 jno .Lnoreset
103 larl %r2,.Lreset
104 lghi %r3,26
105 diag %r2,%r3,8
106 larl %r5,.Lirb
107 stsch 0(%r5) # check if irq is pending
108 tm 30(%r5),0x0f # by verifying if any of the
109 jnz .Lwaitforirq # activity or status control
110 tm 31(%r5),0xff # bits is set in the schib
111 jz .Lnoreset
112.Lwaitforirq:
113 bras %r14,.Lirqwait # wait for IO interrupt
114 c %r1,__LC_SUBCHANNEL_ID # compare subchannel number
115 jne .Lwaitforirq
116 larl %r5,.Lirb
117 tsch 0(%r5)
118.Lnoreset:
119 j .Lnoload
120#
121# everything loaded, go for it
122#
123.Lnoload:
124 jg startup
125#
126# subroutine to wait for end I/O
127#
128.Lirqwait:
129 larl %r13,.Lnewpswmask # set up IO interrupt psw
130 mvc __LC_IO_NEW_PSW(8),0(%r13)
131 stg %r14,__LC_IO_NEW_PSW+8
132 larl %r13,.Lwaitpsw
133 lpswe 0(%r13)
134.Lioint:
135#
136# subroutine for loading cards from the reader
137#
138.Lloader:
139 lgr %r4,%r14
140 larl %r3,.Lorb # r2 = address of orb into r2
141 larl %r5,.Lirb # r4 = address of irb
142 larl %r6,.Lccws
143 lghi %r7,20
144.Linit:
145 st %r2,4(%r6) # initialize CCW data addresses
146 la %r2,0x50(%r2)
147 la %r6,8(%r6)
148 brctg %r7,.Linit
149 larl %r13,.Lcr6
150 lctlg %c6,%c6,0(%r13)
151 xgr %r2,%r2
152.Lldlp:
153 ssch 0(%r3) # load chunk of 1600 bytes
154 jnz .Llderr
155.Lwait4irq:
156 bras %r14,.Lirqwait
157 c %r1,__LC_SUBCHANNEL_ID # compare subchannel number
158 jne .Lwait4irq
159 tsch 0(%r5)
160 xgr %r0,%r0
161 ic %r0,8(%r5) # get device status
162 cghi %r0,8 # channel end ?
163 je .Lcont
164 cghi %r0,12 # channel end + device end ?
165 je .Lcont
166 llgf %r0,4(%r5)
167 sgf %r0,8(%r3) # r0/8 = number of ccws executed
168 mghi %r0,10 # *10 = number of bytes in ccws
169 llgh %r3,10(%r5) # get residual count
170 sgr %r0,%r3 # #ccws*80-residual=#bytes read
171 agr %r2,%r0
172 br %r4 # r2 contains the total size
173.Lcont:
174 aghi %r2,0x640 # add 0x640 to total size
175 larl %r6,.Lccws
176 lghi %r7,20
177.Lincr:
178 l %r0,4(%r6) # update CCW data addresses
179 aghi %r0,0x640
180 st %r0,4(%r6)
181 aghi %r6,8
182 brctg %r7,.Lincr
183 j .Lldlp
184.Llderr:
185 larl %r13,.Lcrash
186 lpsw 0(%r13)
187
188 .balign 8
189.Lwaitpsw:
190 .quad 0x0202000180000000,.Lioint
191.Lnewpswmask:
192 .quad 0x0000000180000000
193 .balign 8
194.Lorb: .long 0x00000000,0x0080ff00,.Lccws
195.Lirb: .long 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
196 .balign 8
197.Lcr6: .quad 0x00000000ff000000
198 .balign 8
199.Lcrash:.long 0x000a0000,0x00000000
200 .balign 8
201.Lccws: .rept 19
202 .long 0x02600050,0x00000000
203 .endr
204 .long 0x02200050,0x00000000
205.Lreset:.byte 0xc3,0xc8,0xc1,0xd5,0xc7,0xc5,0x40,0xd9,0xc4,0xd9,0x40
206 .byte 0xc1,0xd3,0xd3,0x40,0xd2,0xc5,0xc5,0xd7,0x40,0xd5,0xd6
207 .byte 0xc8,0xd6,0xd3,0xc4 # "change rdr all keep nohold"
208.L_eof: .long 0xc5d6c600 /* C'EOF' */
209.L_hdr: .long 0xc8c4d900 /* C'HDR' */
210 .balign 8
211.Lcpuid:.fill 8,1,0
212
213#
214# normal startup-code, running in absolute addressing mode
215# this is called either by the ipl loader or directly by PSW restart
216# or linload or SALIPL
217#
218 .org STARTUP_NORMAL_OFFSET - IPL_START
219SYM_CODE_START(startup)
220 j startup_normal
221 .org EP_OFFSET - IPL_START
222#
223# This is a list of s390 kernel entry points. At address 0x1000f the number of
224# valid entry points is stored.
225#
226# IMPORTANT: Do not change this table, it is s390 kernel ABI!
227#
228 .ascii EP_STRING
229 .byte 0x00,0x01
230#
231# kdump startup-code, running in 64 bit absolute addressing mode
232#
233 .org STARTUP_KDUMP_OFFSET - IPL_START
234 j startup_kdump
235SYM_CODE_END(startup)
236SYM_CODE_START_LOCAL(startup_normal)
237 mvi __LC_AR_MODE_ID,1 # set esame flag
238 slr %r0,%r0 # set cpuid to zero
239 lhi %r1,2 # mode 2 = esame (dump)
240 sigp %r1,%r0,0x12 # switch to esame mode
241 bras %r13,0f
242 .fill 16,4,0x0
2430: lmh %r0,%r15,0(%r13) # clear high-order half of gprs
244 sam64 # switch to 64 bit addressing mode
245 larl %r13,.Lext_new_psw
246 mvc __LC_EXT_NEW_PSW(16),0(%r13)
247 larl %r13,.Lpgm_new_psw
248 mvc __LC_PGM_NEW_PSW(16),0(%r13)
249 larl %r13,.Lio_new_psw
250 mvc __LC_IO_NEW_PSW(16),0(%r13)
251 xc 0x200(256),0x200 # partially clear lowcore
252 xc 0x300(256),0x300
253 xc 0xe00(256),0xe00
254 xc 0xf00(256),0xf00
255 larl %r13,.Lctl
256 lctlg %c0,%c15,0(%r13) # load control registers
257 stcke __LC_BOOT_CLOCK
258 mvc __LC_LAST_UPDATE_CLOCK(8),__LC_BOOT_CLOCK+1
259 larl %r13,6f
260 spt 0(%r13)
261 mvc __LC_LAST_UPDATE_TIMER(8),0(%r13)
262 larl %r15,_stack_end-STACK_FRAME_OVERHEAD
263 brasl %r14,sclp_early_setup_buffer
264 brasl %r14,verify_facilities
265 brasl %r14,startup_kernel
266SYM_CODE_END(startup_normal)
267
268 .balign 8
2696: .long 0x7fffffff,0xffffffff
270.Lext_new_psw:
271 .quad 0x0002000180000000,0x1b0 # disabled wait
272.Lpgm_new_psw:
273 .quad 0x0000000180000000,startup_pgm_check_handler
274.Lio_new_psw:
275 .quad 0x0002000180000000,0x1f0 # disabled wait
276.Lctl: .quad 0x04040000 # cr0: AFP registers & secondary space
277 .quad 0 # cr1: primary space segment table
278 .quad 0 # cr2: dispatchable unit control table
279 .quad 0 # cr3: instruction authorization
280 .quad 0xffff # cr4: instruction authorization
281 .quad 0 # cr5: primary-aste origin
282 .quad 0 # cr6: I/O interrupts
283 .quad 0 # cr7: secondary space segment table
284 .quad 0x0000000000008000 # cr8: access registers translation
285 .quad 0 # cr9: tracing off
286 .quad 0 # cr10: tracing off
287 .quad 0 # cr11: tracing off
288 .quad 0 # cr12: tracing off
289 .quad 0 # cr13: home space segment table
290 .quad 0xc0000000 # cr14: machine check handling off
291 .quad 0 # cr15: linkage stack operations
292
293#include "head_kdump.S"
294
295#
296# This program check is active immediately after kernel start
297# and until early_pgm_check_handler is set in kernel/early.c
298# It simply saves general/control registers and psw in
299# the save area and does disabled wait with a faulty address.
300#
301SYM_CODE_START_LOCAL(startup_pgm_check_handler)
302 stmg %r8,%r15,__LC_SAVE_AREA_SYNC
303 la %r8,4095
304 stctg %c0,%c15,__LC_CREGS_SAVE_AREA-4095(%r8)
305 stmg %r0,%r7,__LC_GPREGS_SAVE_AREA-4095(%r8)
306 mvc __LC_GPREGS_SAVE_AREA-4095+64(64,%r8),__LC_SAVE_AREA_SYNC
307 mvc __LC_PSW_SAVE_AREA-4095(16,%r8),__LC_PGM_OLD_PSW
308 mvc __LC_RETURN_PSW(16),__LC_PGM_OLD_PSW
309 ni __LC_RETURN_PSW,0xfc # remove IO and EX bits
310 ni __LC_RETURN_PSW+1,0xfb # remove MCHK bit
311 oi __LC_RETURN_PSW+1,0x2 # set wait state bit
312 larl %r9,.Lold_psw_disabled_wait
313 stg %r9,__LC_PGM_NEW_PSW+8
314 larl %r15,_dump_info_stack_end-STACK_FRAME_OVERHEAD
315 brasl %r14,print_pgm_check_info
316.Lold_psw_disabled_wait:
317 la %r8,4095
318 lmg %r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r8)
319 lpswe __LC_RETURN_PSW # disabled wait
320SYM_CODE_END(startup_pgm_check_handler)
321

source code of linux/arch/s390/boot/head.S