2 * arch/s390/kernel/head31.S
4 * Copyright (C) IBM Corp. 2005,2006
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>
14 # startup-code at 0x10000, running in absolute addressing mode
15 # this is called either by the ipl loader or directly by PSW restart
16 # or linload or SALIPL
19 startup:basr %r13,0 # get base
20 .LPG0: l %r13,0f-.LPG0(%r13)
22 0: .long startup_continue
25 # params at 10400 (setup.h)
28 .long 0,0 # IPL_DEVICE
29 .long 0,0 # INITRD_START
30 .long 0,0 # INITRD_SIZE
33 .byte "root=/dev/ram0 ro"
39 basr %r13,0 # get base
40 .LPG1: mvi __LC_AR_MODE_ID,0 # set ESA flag (mode 0)
41 lctl %c0,%c15,.Lctl-.LPG1(%r13) # load control registers
42 l %r12,.Lparmaddr-.LPG1(%r13) # pointer to parameter area
43 # move IPL device to lowcore
44 mvc __LC_IPLDEV(4),IPL_DEVICE-PARMAREA(%r12)
48 l %r15,.Linittu-.LPG1(%r13)
49 mvc __LC_CURRENT(4),__TI_task(%r15)
50 ahi %r15,1<<(PAGE_SHIFT+THREAD_ORDER) # init_task_union+THREAD_SIZE
51 st %r15,__LC_KERNEL_STACK # set end of kernel stack
53 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) # clear backchain
55 # Save ipl parameters, clear bss memory, initialize storage key for kernel pages,
56 # and create a kernel NSS if the SAVESYS= parm is defined
58 l %r14,.Lstartup_init-.LPG1(%r13)
61 l %r2,.Lrcp-.LPG1(%r13) # Read SCP forced command word
63 stosm .Lpmask-.LPG1(%r13),0x01 # authorize ext interrupts
65 stctl %r0, %r0,.Lcr-.LPG1(%r13) # get cr0
66 la %r1,0x200 # set bit 22
67 o %r1,.Lcr-.LPG1(%r13) # or old cr0 with r1
68 st %r1,.Lcr-.LPG1(%r13)
69 lctl %r0, %r0,.Lcr-.LPG1(%r13) # load modified cr0
71 mvc __LC_EXT_NEW_PSW(8),.Lpcext-.LPG1(%r13) # set postcall psw
72 la %r1, .Lsclph-.LPG1(%r13)
73 a %r1,__LC_EXT_NEW_PSW+4 # set handler
74 st %r1,__LC_EXT_NEW_PSW+4
76 l %r4,.Lsccbaddr-.LPG1(%r13) # %r4 is our index for sccb stuff
78 .insn rre,0xb2200000,%r2,%r1 # service call
80 srl %r1,28 # get cc code
83 be .Lfchunk-.LPG1(%r13) # leave
85 be .Lservicecall-.LPG1(%r13)
86 lpsw .Lwaitsclp-.LPG1(%r13)
88 lh %r1,.Lsccbr-.Lsccb(%r4)
89 chi %r1,0x10 # 0x0010 is the sucess code
90 je .Lprocsccb # let's process the sccb
92 bne .Lfchunk-.LPG1(%r13) # unhandled error code
93 c %r2, .Lrcp-.LPG1(%r13) # Did we try Read SCP forced
94 bne .Lfchunk-.LPG1(%r13) # if no, give up
95 l %r2, .Lrcp2-.LPG1(%r13) # try with Read SCP
96 b .Lservicecall-.LPG1(%r13)
99 icm %r1,3,.Lscpincr1-.Lsccb(%r4) # use this one if != 0
101 lhi %r1,0x800 # otherwise report 2GB
103 lhi %r3,0x800 # limit reported memory size to 2GB
108 xr %r3,%r3 # same logic
109 ic %r3,.Lscpa1-.Lsccb(%r4)
112 l %r3,.Lscpa2-.Lsccb(%r4)
114 mr %r2,%r1 # mem in MB on 128-bit
115 l %r1,.Lonemb-.LPG1(%r13)
116 mr %r2,%r1 # mem size in bytes in %r3
117 b .Lfchunk-.LPG1(%r13)
121 .long init_thread_union
127 .Lpcext:.long 0x00080000,0x80000000
129 .long 0x00 # place holder for cr0
132 .long 0x010a0000,0x80000000 + .Lsclph
134 .int 0x00120001 # Read SCP forced code
136 .int 0x00020001 # Read SCP code
142 # find memory chunks.
144 lr %r9,%r3 # end of mem
145 mvc __LC_PGM_NEW_PSW(8),.Lpcmem-.LPG1(%r13)
146 la %r1,1 # test in increments of 128KB
148 l %r3,.Lmchunk-.LPG1(%r13) # get pointer to memory_chunk array
149 slr %r4,%r4 # set start of chunk to zero
150 slr %r5,%r5 # set end of chunk to zero
151 slr %r6,%r6 # set access code to zero
152 la %r10,MEMORY_CHUNKS # number of chunks
154 tprot 0(%r5),0 # test protection of first byte
157 clr %r6,%r7 # compare cc with last access code
158 be .Lsame-.LPG1(%r13)
159 lhi %r8,0 # no program checks
160 b .Lsavchk-.LPG1(%r13)
162 ar %r5,%r1 # add 128KB to end of chunk
163 bno .Lloop-.LPG1(%r13) # r1 < 0x80000000 -> loop
164 .Lchkmem: # > 2GB or tprot got a program check
165 lhi %r8,1 # set program check flag
167 clr %r4,%r5 # chunk size > 0?
168 be .Lchkloop-.LPG1(%r13)
169 st %r4,0(%r3) # store start address of chunk
172 st %r0,4(%r3) # store size of chunk
173 st %r6,8(%r3) # store type of chunk
175 ahi %r10,-1 # update chunk number
177 lr %r6,%r7 # set access code to last cc
178 # we got an exception or we're starting a new
179 # chunk , we must check if we should
180 # still try to find valid memory (if we detected
181 # the amount of available storage), and if we
184 clr %r0,%r9 # did we detect memory?
185 je .Ldonemem # if not, leave
186 chi %r10,0 # do we have chunks left?
188 chi %r8,1 # program check ?
190 lr %r4,%r5 # potential new chunk
191 alr %r5,%r1 # add 128KB to end of chunk
194 alr %r5,%r1 # add 128KB to end of chunk
195 lr %r4,%r5 # potential new chunk
197 clr %r5,%r9 # should we go on?
200 l %r12,.Lmflags-.LPG1(%r13) # get address of machine_flags
202 # find out if we have an IEEE fpu
204 mvc __LC_PGM_NEW_PSW(8),.Lpcfpu-.LPG1(%r13)
205 efpc %r0,0 # test IEEE extract fpc instruction
206 oi 3(%r12),2 # set IEEE fpu flag
210 # find out if we have the CSP instruction
212 mvc __LC_PGM_NEW_PSW(8),.Lpccsp-.LPG1(%r13)
216 csp %r0,%r2 # Test CSP instruction
217 oi 3(%r12),8 # set CSP flag
221 # find out if we have the MVPG instruction
223 mvc __LC_PGM_NEW_PSW(8),.Lpcmvpg-.LPG1(%r13)
227 mvpg %r1,%r2 # Test CSP instruction
228 oi 3(%r12),16 # set MVPG flag
232 # find out if we have the IDTE instruction
234 mvc __LC_PGM_NEW_PSW(8),.Lpcidte-.LPG1(%r13)
235 .long 0xb2b10000 # store facility list
236 tm 0xc8,0x08 # check bit for clearing-by-ASCE
237 bno .Lchkidte-.LPG1(%r13)
241 oi 3(%r12),0x80 # set IDTE flag
245 # find out if the diag 0x9c is available
247 mvc __LC_PGM_NEW_PSW(8),.Lpcdiag9c-.LPG1(%r13)
248 stap __LC_CPUID+4 # store cpu address
250 diag %r1,0,0x9c # test diag 0x9c
251 oi 2(%r12),1 # set diag9c flag
254 lpsw .Lentry-.LPG1(13) # jump to _stext in primary-space,
255 # virtual and never return ...
257 .Lentry:.long 0x00080000,0x80000000 + _stext
258 .Lctl: .long 0x04b50002 # cr0: various things
259 .long 0 # cr1: primary space segment table
260 .long .Lduct # cr2: dispatchable unit control table
261 .long 0 # cr3: instruction authorization
262 .long 0 # cr4: instruction authorization
263 .long 0xffffffff # cr5: primary-aste origin
264 .long 0 # cr6: I/O interrupts
265 .long 0 # cr7: secondary space segment table
266 .long 0 # cr8: access registers translation
267 .long 0 # cr9: tracing off
268 .long 0 # cr10: tracing off
269 .long 0 # cr11: tracing off
270 .long 0 # cr12: tracing off
271 .long 0 # cr13: home space segment table
272 .long 0xc0000000 # cr14: machine check handling off
273 .long 0 # cr15: linkage stack operations
274 .Lduct: .long 0,0,0,0,0,0,0,0
275 .long 0,0,0,0,0,0,0,0
276 .Lpcmem:.long 0x00080000,0x80000000 + .Lchkmem
277 .Lpcfpu:.long 0x00080000,0x80000000 + .Lchkfpu
278 .Lpccsp:.long 0x00080000,0x80000000 + .Lchkcsp
279 .Lpcmvpg:.long 0x00080000,0x80000000 + .Lchkmvpg
280 .Lpcidte:.long 0x00080000,0x80000000 + .Lchkidte
281 .Lpcdiag9c:.long 0x00080000,0x80000000 + .Lchkdiag9c
282 .Lmchunk:.long memory_chunk
283 .Lmflags:.long machine_flags
284 .Lbss_bgn: .long __bss_start
285 .Lbss_end: .long _end
286 .Lparmaddr: .long PARMAREA
287 .Lsccbaddr: .long .Lsccb
303 .globl s390_readinfo_sccb
306 .hword 0x1000 # length, one page
308 .byte 0x80 # variable response bit set
310 .hword 0x00 # response code
323 #ifdef CONFIG_SHARED_KERNEL
328 # startup-code, running in absolute addressing mode
331 _stext: basr %r13,0 # get base
333 # check control registers
334 stctl %c0,%c15,0(%r15)
335 oi 2(%r15),0x40 # enable sigp emergency signal
336 oi 0(%r15),0x10 # switch on low address protection
337 lctl %c0,%c15,0(%r15)
340 lam 0,15,.Laregs-.LPG3(%r13) # load access regs needed by uaccess
341 l %r14,.Lstart-.LPG3(%r13)
342 basr %r14,%r14 # call start_kernel
344 # We returned from start_kernel ?!? PANIK
347 lpsw .Ldw-.(%r13) # load disabled wait psw
350 .Ldw: .long 0x000a0000,0x00000000
351 .Lstart:.long start_kernel
352 .Laregs:.long 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0