/*
* arch/s390/kernel/head64.S
*
* (C) Copyright IBM Corp. 1999,2005
*
* 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
.LPG1: sll %r13,1 # remove high order bit
srl %r13,1
l %r1,.Lget_ipl_device_addr-.LPG1(%r13)
basr %r14,%r1
lhi %r1,1 # mode 1 = esame
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
larl %r12,_pstart # pointer to parameter area
# move IPL device to lowcore
mvc __LC_IPLDEV(4),IPL_DEVICE+4-PARMAREA(%r12)
#
# clear bss memory
#
larl %r2,__bss_start # start of bss segment
larl %r3,_end # end of bss segment
sgr %r3,%r2 # length of bss
sgr %r4,%r4 #
sgr %r5,%r5 # set src,length and pad to zero
mvcle %r2,%r4,0 # clear mem
jo .-4 # branch back, if not finish
l %r2,.Lrcp-.LPG1(%r13) # Read SCP forced command word
.Lservicecall:
stosm .Lpmask-.LPG1(%r13),0x01 # authorize ext interrupts
stctg %r0,%r0,.Lcr-.LPG1(%r13) # get cr0
la %r1,0x200 # set bit 22
og %r1,.Lcr-.LPG1(%r13) # or old cr0 with r1
stg %r1,.Lcr-.LPG1(%r13)
lctlg %r0,%r0,.Lcr-.LPG1(%r13) # load modified cr0
mvc __LC_EXT_NEW_PSW(8),.Lpcmsk-.LPG1(%r13) # set postcall psw
larl %r1,.Lsclph
stg %r1,__LC_EXT_NEW_PSW+8 # set handler
larl %r4,_pstart # %r4 is our index for sccb stuff
la %r1,.Lsccb-PARMAREA(%r4) # our sccb
.insn rre,0xb2200000,%r2,%r1 # service call
ipm %r1
srl %r1,28 # get cc code
xr %r3,%r3
chi %r1,3
be .Lfchunk-.LPG1(%r13) # leave
chi %r1,2
be .Lservicecall-.LPG1(%r13)
lpswe .Lwaitsclp-.LPG1(%r13)
.Lsclph:
lh %r1,.Lsccbr-PARMAREA(%r4)
chi %r1,0x10 # 0x0010 is the sucess code
je .Lprocsccb # let's process the sccb
chi %r1,0x1f0
bne .Lfchunk-.LPG1(%r13) # unhandled error code
c %r2,.Lrcp-.LPG1(%r13) # Did we try Read SCP forced
bne .Lfchunk-.LPG1(%r13) # if no, give up
l %r2,.Lrcp2-.LPG1(%r13) # try with Read SCP
b .Lservicecall-.LPG1(%r13)
.Lprocsccb:
lghi %r1,0
icm %r1,3,.Lscpincr1-PARMAREA(%r4) # use this one if != 0
jnz .Lscnd
lg %r1,.Lscpincr2-PARMAREA(%r4) # otherwise use this one
.Lscnd:
xr %r3,%r3 # same logic
ic %r3,.Lscpa1-PARMAREA(%r4)
chi %r3,0x00
jne .Lcompmem
l %r3,.Lscpa2-PARMAREA(%r13)
.Lcompmem:
mlgr %r2,%r1 # mem in MB on 128-bit
l %r1,.Lonemb-.LPG1(%r13)
mlgr %r2,%r1 # mem size in bytes in %r3
b .Lfchunk-.LPG1(%r13)
.align 4
.Lget_ipl_device_addr:
.long .Lget_ipl_device
.Lpmask:
.byte 0
.align 8
.Lcr:
.quad 0x00 # place holder for cr0
.Lwaitsclp:
.quad 0x0102000180000000,.Lsclph
.Lrcp:
.int 0x00120001 # Read SCP forced code
.Lrcp2:
.int 0x00020001 # Read SCP code
.Lonemb:
.int 0x100000
.Lfchunk:
# set program check new psw mask
mvc __LC_PGM_NEW_PSW(8),.Lpcmsk-.LPG1(%r13)
#
# find memory chunks.
#
lgr %r9,%r3 # end of mem
larl %r1,.Lchkmem # set program check address
stg %r1,__LC_PGM_NEW_PSW+8
la %r1,1 # test in increments of 128KB
sllg %r1,%r1,17
larl %r3,memory_chunk
slgr %r4,%r4 # set start of chunk to zero
slgr %r5,%r5 # set end of chunk to zero
slr %r6,%r6 # set access code to zero
la %r10,MEMORY_CHUNKS # number of chunks
.Lloop:
tprot 0(%r5),0 # test protection of first byte
ipm %r7
srl %r7,28
clr %r6,%r7 # compare cc with last access code
je .Lsame
j .Lchkmem
.Lsame:
algr %r5,%r1 # add 128KB to end of chunk
# no need to check here,
brc 12,.Lloop # this is the same chunk
.Lchkmem: # > 16EB or tprot got a program check
clgr %r4,%r5 # chunk size > 0?
je .Lchkloop
stg %r4,0(%r3) # store start address of chunk
lgr %r0,%r5
slgr %r0,%r4
stg %r0,8(%r3) # store size of chunk
st %r6,20(%r3) # store type of chunk
la %r3,24(%r3)
larl %r8,memory_size
stg %r5,0(%r8) # store memory size
ahi %r10,-1 # update chunk number
.Lchkloop:
lr %r6,%r7 # set access code to last cc
# we got an exception or we're starting a new
# chunk , we must check if we should
# still try to find valid memory (if we detected
# the amount of available storage), and if we
# have chunks left
lghi %r4,1
sllg %r4,%r4,31
clgr %r5,%r4
je .Lhsaskip
xr %r0, %r0
clgr %r0, %r9 # did we detect memory?
je .Ldonemem # if not, leave
chi %r10, 0 # do we have chunks left?
je .Ldonemem
.Lhsaskip:
algr %r5,%r1 # add 128KB to end of chunk
lgr %r4,%r5 # potential new chunk
clgr %r5,%r9 # should we go on?
jl .Lloop
.Ldonemem:
larl %r12,machine_flags
#
# find out if we are running under VM
#
stidp __LC_CPUID # store cpuid
tm __LC_CPUID,0xff # running under VM ?
bno 0f-.LPG1(%r13)
oi 7(%r12),1 # set VM flag
0: lh %r0,__LC_CPUID+4 # get cpu version
chi %r0,0x7490 # running on a P/390 ?
bne 1f-.LPG1(%r13)
oi 7(%r12),4 # set P/390 flag
1:
#
# 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:
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
.Lpcmsk:.quad 0x0000000180000000
.L4malign:.quad 0xffffffffffc00000
.Lscan2g:.quad 0x80000000 + 0x20000 - 8 # 2GB + 128K - 8
.Lnop: .long 0x07000700
.org PARMAREA-64
.Lduct: .long 0,0,0,0,0,0,0,0
.long 0,0,0,0,0,0,0,0
#
# params at 10400 (setup.h)
#
.org PARMAREA
.global _pstart
_pstart:
.quad 0 # IPL_DEVICE
.quad RAMDISK_ORIGIN # INITRD_START
.quad RAMDISK_SIZE # INITRD_SIZE
.org COMMAND_LINE
.byte "root=/dev/ram0 ro"
.byte 0
.org 0x11000
.Lsccb:
.hword 0x1000 # length, one page
.byte 0x00,0x00,0x00
.byte 0x80 # variable response bit set
.Lsccbr:
.hword 0x00 # response code
.Lscpincr1:
.hword 0x00
.Lscpa1:
.byte 0x00
.fill 89,1,0
.Lscpa2:
.int 0x00
.Lscpincr2:
.quad 0x00
.fill 3984,1,0
.org 0x12000
.global _pend
_pend:
GET_IPL_DEVICE
#ifdef CONFIG_SHARED_KERNEL
.org 0x100000
#endif
#
# startup-code, running in virtual mode
#
.globl _stext
_stext: basr %r13,0 # get base
.LPG3:
#
# 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
# 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 access regs 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