xref: /linux/arch/s390/kernel/head.S (revision b233b28eac0cc37d07c2d007ea08c86c778c5af4) 
1/*
2 *  arch/s390/kernel/head.S
3 *
4 * Copyright (C) IBM Corp. 1999,2006
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 * There are 5 different IPL methods
12 *  1) load the image directly into ram at address 0 and do an PSW restart
13 *  2) linload will load the image from address 0x10000 to memory 0x10000
14 *     and start the code thru LPSW 0x0008000080010000 (VM only, deprecated)
15 *  3) generate the tape ipl header, store the generated image on a tape
16 *     and ipl from it
17 *     In case of SL tape you need to IPL 5 times to get past VOL1 etc
18 *  4) generate the vm reader ipl header, move the generated image to the
19 *     VM reader (use option NOH!) and do a ipl from reader (VM only)
20 *  5) direct call of start by the SALIPL loader
21 *  We use the cpuid to distinguish between VM and native ipl
22 *  params for kernel are pushed to 0x10400 (see setup.h)
23 *
24 */
25
26#include <asm/setup.h>
27#include <asm/lowcore.h>
28#include <asm/asm-offsets.h>
29#include <asm/thread_info.h>
30#include <asm/page.h>
31
32#ifdef CONFIG_64BIT
33#define ARCH_OFFSET	4
34#else
35#define ARCH_OFFSET	0
36#endif
37
38.section ".text.head","ax"
39#ifndef CONFIG_IPL
40	.org   0
41	.long  0x00080000,0x80000000+startup	# Just a restart PSW
42#else
43#ifdef CONFIG_IPL_TAPE
44#define IPL_BS 1024
45	.org   0
46	.long  0x00080000,0x80000000+iplstart	# The first 24 bytes are loaded
47	.long  0x27000000,0x60000001		# by ipl to addresses 0-23.
48	.long  0x02000000,0x20000000+IPL_BS	# (a PSW and two CCWs).
49	.long  0x00000000,0x00000000		# external old psw
50	.long  0x00000000,0x00000000		# svc old psw
51	.long  0x00000000,0x00000000		# program check old psw
52	.long  0x00000000,0x00000000		# machine check old psw
53	.long  0x00000000,0x00000000		# io old psw
54	.long  0x00000000,0x00000000
55	.long  0x00000000,0x00000000
56	.long  0x00000000,0x00000000
57	.long  0x000a0000,0x00000058		# external new psw
58	.long  0x000a0000,0x00000060		# svc new psw
59	.long  0x000a0000,0x00000068		# program check new psw
60	.long  0x000a0000,0x00000070		# machine check new psw
61	.long  0x00080000,0x80000000+.Lioint	# io new psw
62
63	.org   0x100
64#
65# subroutine for loading from tape
66# Paramters:
67#  R1 = device number
68#  R2 = load address
69.Lloader:
70	st	%r14,.Lldret
71	la	%r3,.Lorbread		# r3 = address of orb
72	la	%r5,.Lirb		# r5 = address of irb
73	st	%r2,.Lccwread+4 	# initialize CCW data addresses
74	lctl	%c6,%c6,.Lcr6
75	slr	%r2,%r2
76.Lldlp:
77	la	%r6,3			# 3 retries
78.Lssch:
79	ssch	0(%r3)			# load chunk of IPL_BS bytes
80	bnz	.Llderr
81.Lw4end:
82	bas	%r14,.Lwait4io
83	tm	8(%r5),0x82		# do we have a problem ?
84	bnz	.Lrecov
85	slr	%r7,%r7
86	icm	%r7,3,10(%r5)		# get residual count
87	lcr	%r7,%r7
88	la	%r7,IPL_BS(%r7) 	# IPL_BS-residual=#bytes read
89	ar	%r2,%r7 		# add to total size
90	tm	8(%r5),0x01		# found a tape mark ?
91	bnz	.Ldone
92	l	%r0,.Lccwread+4 	# update CCW data addresses
93	ar	%r0,%r7
94	st	%r0,.Lccwread+4
95	b	.Lldlp
96.Ldone:
97	l	%r14,.Lldret
98	br	%r14			# r2 contains the total size
99.Lrecov:
100	bas	%r14,.Lsense		# do the sensing
101	bct	%r6,.Lssch		# dec. retry count & branch
102	b	.Llderr
103#
104# Sense subroutine
105#
106.Lsense:
107	st	%r14,.Lsnsret
108	la	%r7,.Lorbsense
109	ssch	0(%r7)			# start sense command
110	bnz	.Llderr
111	bas	%r14,.Lwait4io
112	l	%r14,.Lsnsret
113	tm	8(%r5),0x82		# do we have a problem ?
114	bnz	.Llderr
115	br	%r14
116#
117# Wait for interrupt subroutine
118#
119.Lwait4io:
120	lpsw	.Lwaitpsw
121.Lioint:
122	c	%r1,0xb8		# compare subchannel number
123	bne	.Lwait4io
124	tsch	0(%r5)
125	slr	%r0,%r0
126	tm	8(%r5),0x82		# do we have a problem ?
127	bnz	.Lwtexit
128	tm	8(%r5),0x04		# got device end ?
129	bz	.Lwait4io
130.Lwtexit:
131	br	%r14
132.Llderr:
133	lpsw	.Lcrash
134
135	.align	8
136.Lorbread:
137	.long	0x00000000,0x0080ff00,.Lccwread
138	.align	8
139.Lorbsense:
140	.long	0x00000000,0x0080ff00,.Lccwsense
141	.align	8
142.Lccwread:
143	.long	0x02200000+IPL_BS,0x00000000
144.Lccwsense:
145	.long	0x04200001,0x00000000
146.Lwaitpsw:
147	.long	0x020a0000,0x80000000+.Lioint
148
149.Lirb:	.long	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
150.Lcr6:	.long	0xff000000
151	.align	8
152.Lcrash:.long	0x000a0000,0x00000000
153.Lldret:.long	0
154.Lsnsret: .long 0
155#endif	/* CONFIG_IPL_TAPE */
156
157#ifdef CONFIG_IPL_VM
158#define IPL_BS	0x730
159	.org	0
160	.long	0x00080000,0x80000000+iplstart	# The first 24 bytes are loaded
161	.long	0x02000018,0x60000050		# by ipl to addresses 0-23.
162	.long	0x02000068,0x60000050		# (a PSW and two CCWs).
163	.fill	80-24,1,0x40			# bytes 24-79 are discarded !!
164	.long	0x020000f0,0x60000050		# The next 160 byte are loaded
165	.long	0x02000140,0x60000050		# to addresses 0x18-0xb7
166	.long	0x02000190,0x60000050		# They form the continuation
167	.long	0x020001e0,0x60000050		# of the CCW program started
168	.long	0x02000230,0x60000050		# by ipl and load the range
169	.long	0x02000280,0x60000050		# 0x0f0-0x730 from the image
170	.long	0x020002d0,0x60000050		# to the range 0x0f0-0x730
171	.long	0x02000320,0x60000050		# in memory. At the end of
172	.long	0x02000370,0x60000050		# the channel program the PSW
173	.long	0x020003c0,0x60000050		# at location 0 is loaded.
174	.long	0x02000410,0x60000050		# Initial processing starts
175	.long	0x02000460,0x60000050		# at 0xf0 = iplstart.
176	.long	0x020004b0,0x60000050
177	.long	0x02000500,0x60000050
178	.long	0x02000550,0x60000050
179	.long	0x020005a0,0x60000050
180	.long	0x020005f0,0x60000050
181	.long	0x02000640,0x60000050
182	.long	0x02000690,0x60000050
183	.long	0x020006e0,0x20000050
184
185	.org	0xf0
186#
187# subroutine for loading cards from the reader
188#
189.Lloader:
190	la	%r3,.Lorb		# r2 = address of orb into r2
191	la	%r5,.Lirb		# r4 = address of irb
192	la	%r6,.Lccws
193	la	%r7,20
194.Linit:
195	st	%r2,4(%r6)		# initialize CCW data addresses
196	la	%r2,0x50(%r2)
197	la	%r6,8(%r6)
198	bct	7,.Linit
199
200	lctl	%c6,%c6,.Lcr6		# set IO subclass mask
201	slr	%r2,%r2
202.Lldlp:
203	ssch	0(%r3)			# load chunk of 1600 bytes
204	bnz	.Llderr
205.Lwait4irq:
206	mvc	0x78(8),.Lnewpsw	# set up IO interrupt psw
207	lpsw	.Lwaitpsw
208.Lioint:
209	c	%r1,0xb8		# compare subchannel number
210	bne	.Lwait4irq
211	tsch	0(%r5)
212
213	slr	%r0,%r0
214	ic	%r0,8(%r5)		# get device status
215	chi	%r0,8			# channel end ?
216	be	.Lcont
217	chi	%r0,12			# channel end + device end ?
218	be	.Lcont
219
220	l	%r0,4(%r5)
221	s	%r0,8(%r3)		# r0/8 = number of ccws executed
222	mhi	%r0,10			# *10 = number of bytes in ccws
223	lh	%r3,10(%r5)		# get residual count
224	sr	%r0,%r3 		# #ccws*80-residual=#bytes read
225	ar	%r2,%r0
226
227	br	%r14			# r2 contains the total size
228
229.Lcont:
230	ahi	%r2,0x640		# add 0x640 to total size
231	la	%r6,.Lccws
232	la	%r7,20
233.Lincr:
234	l	%r0,4(%r6)		# update CCW data addresses
235	ahi	%r0,0x640
236	st	%r0,4(%r6)
237	ahi	%r6,8
238	bct	7,.Lincr
239
240	b	.Lldlp
241.Llderr:
242	lpsw	.Lcrash
243
244	.align	8
245.Lorb:	.long	0x00000000,0x0080ff00,.Lccws
246.Lirb:	.long	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
247.Lcr6:	.long	0xff000000
248.Lloadp:.long	0,0
249	.align	8
250.Lcrash:.long	0x000a0000,0x00000000
251.Lnewpsw:
252	.long	0x00080000,0x80000000+.Lioint
253.Lwaitpsw:
254	.long	0x020a0000,0x80000000+.Lioint
255
256	.align	8
257.Lccws: .rept	19
258	.long	0x02600050,0x00000000
259	.endr
260	.long	0x02200050,0x00000000
261#endif	/* CONFIG_IPL_VM */
262
263iplstart:
264	lh	%r1,0xb8		# test if subchannel number
265	bct	%r1,.Lnoload		#  is valid
266	l	%r1,0xb8		# load ipl subchannel number
267	la	%r2,IPL_BS		# load start address
268	bas	%r14,.Lloader		# load rest of ipl image
269	l	%r12,.Lparm		# pointer to parameter area
270	st	%r1,IPL_DEVICE+ARCH_OFFSET-PARMAREA(%r12) # save ipl device number
271
272#
273# load parameter file from ipl device
274#
275.Lagain1:
276	l	%r2,.Linitrd		# ramdisk loc. is temp
277	bas	%r14,.Lloader		# load parameter file
278	ltr	%r2,%r2 		# got anything ?
279	bz	.Lnopf
280	chi	%r2,895
281	bnh	.Lnotrunc
282	la	%r2,895
283.Lnotrunc:
284	l	%r4,.Linitrd
285	clc	0(3,%r4),.L_hdr		# if it is HDRx
286	bz	.Lagain1		# skip dataset header
287	clc	0(3,%r4),.L_eof		# if it is EOFx
288	bz	.Lagain1		# skip dateset trailer
289	la	%r5,0(%r4,%r2)
290	lr	%r3,%r2
291.Lidebc:
292	tm	0(%r5),0x80		# high order bit set ?
293	bo	.Ldocv			#  yes -> convert from EBCDIC
294	ahi	%r5,-1
295	bct	%r3,.Lidebc
296	b	.Lnocv
297.Ldocv:
298	l	%r3,.Lcvtab
299	tr	0(256,%r4),0(%r3)	# convert parameters to ascii
300	tr	256(256,%r4),0(%r3)
301	tr	512(256,%r4),0(%r3)
302	tr	768(122,%r4),0(%r3)
303.Lnocv: la	%r3,COMMAND_LINE-PARMAREA(%r12) # load adr. of command line
304	mvc	0(256,%r3),0(%r4)
305	mvc	256(256,%r3),256(%r4)
306	mvc	512(256,%r3),512(%r4)
307	mvc	768(122,%r3),768(%r4)
308	slr	%r0,%r0
309	b	.Lcntlp
310.Ldelspc:
311	ic	%r0,0(%r2,%r3)
312	chi	%r0,0x20		# is it a space ?
313	be	.Lcntlp
314	ahi	%r2,1
315	b	.Leolp
316.Lcntlp:
317	brct	%r2,.Ldelspc
318.Leolp:
319	slr	%r0,%r0
320	stc	%r0,0(%r2,%r3)		# terminate buffer
321.Lnopf:
322
323#
324# load ramdisk from ipl device
325#
326.Lagain2:
327	l	%r2,.Linitrd		# addr of ramdisk
328	st	%r2,INITRD_START+ARCH_OFFSET-PARMAREA(%r12)
329	bas	%r14,.Lloader		# load ramdisk
330	st	%r2,INITRD_SIZE+ARCH_OFFSET-PARMAREA(%r12) # store size of rd
331	ltr	%r2,%r2
332	bnz	.Lrdcont
333	st	%r2,INITRD_START+ARCH_OFFSET-PARMAREA(%r12) # no ramdisk found
334.Lrdcont:
335	l	%r2,.Linitrd
336
337	clc	0(3,%r2),.L_hdr		# skip HDRx and EOFx
338	bz	.Lagain2
339	clc	0(3,%r2),.L_eof
340	bz	.Lagain2
341
342#ifdef CONFIG_IPL_VM
343#
344# reset files in VM reader
345#
346	stidp	__LC_CPUID		# store cpuid
347	tm	__LC_CPUID,0xff 	# running VM ?
348	bno	.Lnoreset
349	la	%r2,.Lreset
350	lhi	%r3,26
351	diag	%r2,%r3,8
352	la	%r5,.Lirb
353	stsch	0(%r5)			# check if irq is pending
354	tm	30(%r5),0x0f		# by verifying if any of the
355	bnz	.Lwaitforirq		# activity or status control
356	tm	31(%r5),0xff		# bits is set in the schib
357	bz	.Lnoreset
358.Lwaitforirq:
359	mvc	0x78(8),.Lrdrnewpsw	# set up IO interrupt psw
360.Lwaitrdrirq:
361	lpsw	.Lrdrwaitpsw
362.Lrdrint:
363	c	%r1,0xb8		# compare subchannel number
364	bne	.Lwaitrdrirq
365	la	%r5,.Lirb
366	tsch	0(%r5)
367.Lnoreset:
368	b	.Lnoload
369
370	.align	8
371.Lrdrnewpsw:
372	.long	0x00080000,0x80000000+.Lrdrint
373.Lrdrwaitpsw:
374	.long	0x020a0000,0x80000000+.Lrdrint
375#endif
376
377#
378# everything loaded, go for it
379#
380.Lnoload:
381	l	%r1,.Lstartup
382	br	%r1
383
384.Linitrd:.long _end + 0x400000		# default address of initrd
385.Lparm:	.long  PARMAREA
386.Lstartup: .long startup
387.Lcvtab:.long	_ebcasc 		# ebcdic to ascii table
388.Lreset:.byte	0xc3,0xc8,0xc1,0xd5,0xc7,0xc5,0x40,0xd9,0xc4,0xd9,0x40
389	.byte	0xc1,0xd3,0xd3,0x40,0xd2,0xc5,0xc5,0xd7,0x40,0xd5,0xd6
390	.byte	0xc8,0xd6,0xd3,0xc4	# "change rdr all keep nohold"
391.L_eof: .long	0xc5d6c600	 /* C'EOF' */
392.L_hdr: .long	0xc8c4d900	 /* C'HDR' */
393
394#endif	/* CONFIG_IPL */
395
396#
397# SALIPL loader support. Based on a patch by Rob van der Heij.
398# This entry point is called directly from the SALIPL loader and
399# doesn't need a builtin ipl record.
400#
401	.org	0x800
402	.globl	start
403start:
404	stm	%r0,%r15,0x07b0		# store registers
405	basr	%r12,%r0
406.base:
407	l	%r11,.parm
408	l	%r8,.cmd		# pointer to command buffer
409
410	ltr	%r9,%r9			# do we have SALIPL parameters?
411	bp	.sk8x8
412
413	mvc	0(64,%r8),0x00b0	# copy saved registers
414	xc	64(240-64,%r8),0(%r8)	# remainder of buffer
415	tr	0(64,%r8),.lowcase
416	b	.gotr
417.sk8x8:
418	mvc	0(240,%r8),0(%r9)	# copy iplparms into buffer
419.gotr:
420	l	%r10,.tbl		# EBCDIC to ASCII table
421	tr	0(240,%r8),0(%r10)
422	slr	%r0,%r0
423	st	%r0,INITRD_SIZE+ARCH_OFFSET-PARMAREA(%r11)
424	st	%r0,INITRD_START+ARCH_OFFSET-PARMAREA(%r11)
425	j	startup 		# continue with startup
426.tbl:	.long	_ebcasc			# translate table
427.cmd:	.long	COMMAND_LINE		# address of command line buffer
428.parm:	.long	PARMAREA
429.lowcase:
430	.byte 0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07
431	.byte 0x08,0x09,0x0a,0x0b,0x0c,0x0d,0x0e,0x0f
432	.byte 0x10,0x11,0x12,0x13,0x14,0x15,0x16,0x17
433	.byte 0x18,0x19,0x1a,0x1b,0x1c,0x1d,0x1e,0x1f
434	.byte 0x20,0x21,0x22,0x23,0x24,0x25,0x26,0x27
435	.byte 0x28,0x29,0x2a,0x2b,0x2c,0x2d,0x2e,0x2f
436	.byte 0x30,0x31,0x32,0x33,0x34,0x35,0x36,0x37
437	.byte 0x38,0x39,0x3a,0x3b,0x3c,0x3d,0x3e,0x3f
438	.byte 0x40,0x41,0x42,0x43,0x44,0x45,0x46,0x47
439	.byte 0x48,0x49,0x4a,0x4b,0x4c,0x4d,0x4e,0x4f
440	.byte 0x50,0x51,0x52,0x53,0x54,0x55,0x56,0x57
441	.byte 0x58,0x59,0x5a,0x5b,0x5c,0x5d,0x5e,0x5f
442	.byte 0x60,0x61,0x62,0x63,0x64,0x65,0x66,0x67
443	.byte 0x68,0x69,0x6a,0x6b,0x6c,0x6d,0x6e,0x6f
444	.byte 0x70,0x71,0x72,0x73,0x74,0x75,0x76,0x77
445	.byte 0x78,0x79,0x7a,0x7b,0x7c,0x7d,0x7e,0x7f
446
447	.byte 0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87
448	.byte 0x88,0x89,0x8a,0x8b,0x8c,0x8d,0x8e,0x8f
449	.byte 0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97
450	.byte 0x98,0x99,0x9a,0x9b,0x9c,0x9d,0x9e,0x9f
451	.byte 0xa0,0xa1,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7
452	.byte 0xa8,0xa9,0xaa,0xab,0xac,0xad,0xae,0xaf
453	.byte 0xb0,0xb1,0xb2,0xb3,0xb4,0xb5,0xb6,0xb7
454	.byte 0xb8,0xb9,0xba,0xbb,0xbc,0xbd,0xbe,0xbf
455	.byte 0xc0,0x81,0x82,0x83,0x84,0x85,0x86,0x87	# .abcdefg
456	.byte 0x88,0x89,0xca,0xcb,0xcc,0xcd,0xce,0xcf	# hi
457	.byte 0xd0,0x91,0x92,0x93,0x94,0x95,0x96,0x97	# .jklmnop
458	.byte 0x98,0x99,0xda,0xdb,0xdc,0xdd,0xde,0xdf	# qr
459	.byte 0xe0,0xe1,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7	# ..stuvwx
460	.byte 0xa8,0xa9,0xea,0xeb,0xec,0xed,0xee,0xef	# yz
461	.byte 0xf0,0xf1,0xf2,0xf3,0xf4,0xf5,0xf6,0xf7
462	.byte 0xf8,0xf9,0xfa,0xfb,0xfc,0xfd,0xfe,0xff
463
464#
465# startup-code at 0x10000, running in absolute addressing mode
466# this is called either by the ipl loader or directly by PSW restart
467# or linload or SALIPL
468#
469	.org	0x10000
470startup:basr	%r13,0			# get base
471.LPG0:
472
473#ifndef CONFIG_MARCH_G5
474	# check processor version against MARCH_{G5,Z900,Z990,Z9_109,Z10}
475	stidp	__LC_CPUID		# store cpuid
476	lhi	%r0,(3f-2f) / 2
477	la	%r1,2f-.LPG0(%r13)
4780:	clc	__LC_CPUID+4(2),0(%r1)
479	jne	3f
480	lpsw	1f-.LPG0(13)		# machine type not good enough, crash
481	.align 16
4821:	.long	0x000a0000,0x00000000
4832:
484#if defined(CONFIG_MARCH_Z10)
485	.short 0x9672, 0x2064, 0x2066, 0x2084, 0x2086, 0x2094, 0x2096
486#elif defined(CONFIG_MARCH_Z9_109)
487	.short 0x9672, 0x2064, 0x2066, 0x2084, 0x2086
488#elif defined(CONFIG_MARCH_Z990)
489	.short 0x9672, 0x2064, 0x2066
490#elif defined(CONFIG_MARCH_Z900)
491	.short 0x9672
492#endif
4933:	la	%r1,2(%r1)
494	brct	%r0,0b
495#endif
496
497	l	%r13,0f-.LPG0(%r13)
498	b	0(%r13)
4990:	.long	startup_continue
500
501#
502# params at 10400 (setup.h)
503#
504	.org	PARMAREA
505	.long	0,0			# IPL_DEVICE
506	.long	0,0			# INITRD_START
507	.long	0,0			# INITRD_SIZE
508
509	.org	COMMAND_LINE
510	.byte	"root=/dev/ram0 ro"
511	.byte	0
512
513#ifdef CONFIG_64BIT
514#include "head64.S"
515#else
516#include "head31.S"
517#endif
518