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Diffstat (limited to 'arch/s390/kernel/head31.S')
| -rw-r--r-- | arch/s390/kernel/head31.S | 336 |
1 files changed, 336 insertions, 0 deletions
diff --git a/arch/s390/kernel/head31.S b/arch/s390/kernel/head31.S new file mode 100644 index 0000000..2d3b089 --- /dev/null +++ b/arch/s390/kernel/head31.S @@ -0,0 +1,336 @@ +/* + * arch/s390/kernel/head31.S + * + * (C) Copyright IBM Corp. 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: l %r1, .Lget_ipl_device_addr-.LPG1(%r13) + basr %r14, %r1 + lctl %c0,%c15,.Lctl-.LPG1(%r13) # load control registers + la %r12,_pstart-.LPG1(%r13) # pointer to parameter area + # move IPL device to lowcore + mvc __LC_IPLDEV(4),IPL_DEVICE-PARMAREA(%r12) + +# +# clear bss memory +# + l %r2,.Lbss_bgn-.LPG1(%r13) # start of bss + l %r3,.Lbss_end-.LPG1(%r13) # end of bss + sr %r3,%r2 # length of bss + sr %r4,%r4 + sr %r5,%r5 # set src,length and pad to zero + sr %r0,%r0 + 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 + + stctl %r0, %r0,.Lcr-.LPG1(%r13) # get cr0 + la %r1,0x200 # set bit 22 + o %r1,.Lcr-.LPG1(%r13) # or old cr0 with r1 + st %r1,.Lcr-.LPG1(%r13) + lctl %r0, %r0,.Lcr-.LPG1(%r13) # load modified cr0 + + mvc __LC_EXT_NEW_PSW(8),.Lpcext-.LPG1(%r13) # set postcall psw + la %r1, .Lsclph-.LPG1(%r13) + a %r1,__LC_EXT_NEW_PSW+4 # set handler + st %r1,__LC_EXT_NEW_PSW+4 + + la %r4,_pstart-.LPG1(%r13) # %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) + lpsw .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: + lhi %r1,0 + icm %r1,3,.Lscpincr1-PARMAREA(%r4) # use this one if != 0 + jnz .Lscnd + lhi %r1,0x800 # otherwise report 2GB +.Lscnd: + lhi %r3,0x800 # limit reported memory size to 2GB + cr %r1,%r3 + jl .Lno2gb + lr %r1,%r3 +.Lno2gb: + xr %r3,%r3 # same logic + ic %r3,.Lscpa1-PARMAREA(%r4) + chi %r3,0x00 + jne .Lcompmem + l %r3,.Lscpa2-PARMAREA(%r13) +.Lcompmem: + mr %r2,%r1 # mem in MB on 128-bit + l %r1,.Lonemb-.LPG1(%r13) + mr %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 +.Lpcext:.long 0x00080000,0x80000000 +.Lcr: + .long 0x00 # place holder for cr0 +.Lwaitsclp: + .long 0x010a0000,0x80000000 + .Lsclph +.Lrcp: + .int 0x00120001 # Read SCP forced code +.Lrcp2: + .int 0x00020001 # Read SCP code +.Lonemb: + .int 0x100000 +.Lfchunk: + +# +# find memory chunks. +# + lr %r9,%r3 # end of mem + mvc __LC_PGM_NEW_PSW(8),.Lpcmem-.LPG1(%r13) + la %r1,1 # test in increments of 128KB + sll %r1,17 + l %r3,.Lmchunk-.LPG1(%r13) # get pointer to memory_chunk array + slr %r4,%r4 # set start of chunk to zero + slr %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 + be .Lsame-.LPG1(%r13) + b .Lchkmem-.LPG1(%r13) +.Lsame: + ar %r5,%r1 # add 128KB to end of chunk + bno .Lloop-.LPG1(%r13) # r1 < 0x80000000 -> loop +.Lchkmem: # > 2GB or tprot got a program check + clr %r4,%r5 # chunk size > 0? + be .Lchkloop-.LPG1(%r13) + st %r4,0(%r3) # store start address of chunk + lr %r0,%r5 + slr %r0,%r4 + st %r0,4(%r3) # store size of chunk + st %r6,8(%r3) # store type of chunk + la %r3,12(%r3) + l %r4,.Lmemsize-.LPG1(%r13) # address of variable memory_size + st %r5,0(%r4) # store last end to 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 + xr %r0,%r0 + clr %r0,%r9 # did we detect memory? + je .Ldonemem # if not, leave + chi %r10,0 # do we have chunks left? + je .Ldonemem + alr %r5,%r1 # add 128KB to end of chunk + lr %r4,%r5 # potential new chunk + clr %r5,%r9 # should we go on? + jl .Lloop +.Ldonemem: + l %r12,.Lmflags-.LPG1(%r13) # get address of machine_flags +# +# find out if we are running under VM +# + stidp __LC_CPUID # store cpuid + tm __LC_CPUID,0xff # running under VM ? + bno .Lnovm-.LPG1(%r13) + oi 3(%r12),1 # set VM flag +.Lnovm: + lh %r0,__LC_CPUID+4 # get cpu version + chi %r0,0x7490 # running on a P/390 ? + bne .Lnop390-.LPG1(%r13) + oi 3(%r12),4 # set P/390 flag +.Lnop390: + +# +# find out if we have an IEEE fpu +# + mvc __LC_PGM_NEW_PSW(8),.Lpcfpu-.LPG1(%r13) + efpc %r0,0 # test IEEE extract fpc instruction + oi 3(%r12),2 # set IEEE fpu flag +.Lchkfpu: + +# +# find out if we have the CSP instruction +# + mvc __LC_PGM_NEW_PSW(8),.Lpccsp-.LPG1(%r13) + la %r0,0 + lr %r1,%r0 + la %r2,4 + csp %r0,%r2 # Test CSP instruction + oi 3(%r12),8 # set CSP flag +.Lchkcsp: + +# +# find out if we have the MVPG instruction +# + mvc __LC_PGM_NEW_PSW(8),.Lpcmvpg-.LPG1(%r13) + sr %r0,%r0 + la %r1,0 + la %r2,0 + mvpg %r1,%r2 # Test CSP instruction + oi 3(%r12),16 # set MVPG flag +.Lchkmvpg: + +# +# find out if we have the IDTE instruction +# + mvc __LC_PGM_NEW_PSW(8),.Lpcidte-.LPG1(%r13) + .long 0xb2b10000 # store facility list + tm 0xc8,0x08 # check bit for clearing-by-ASCE + bno .Lchkidte-.LPG1(%r13) + lhi %r1,2094 + lhi %r2,0 + .long 0xb98e2001 + oi 3(%r12),0x80 # set IDTE flag +.Lchkidte: + + lpsw .Lentry-.LPG1(13) # jump to _stext in primary-space, + # virtual and never return ... + .align 8 +.Lentry:.long 0x00080000,0x80000000 + _stext +.Lctl: .long 0x04b50002 # cr0: various things + .long 0 # cr1: primary space segment table + .long .Lduct # cr2: dispatchable unit control table + .long 0 # cr3: instruction authorization + .long 0 # cr4: instruction authorization + .long 0xffffffff # cr5: primary-aste origin + .long 0 # cr6: I/O interrupts + .long 0 # cr7: secondary space segment table + .long 0 # cr8: access registers translation + .long 0 # cr9: tracing off + .long 0 # cr10: tracing off + .long 0 # cr11: tracing off + .long 0 # cr12: tracing off + .long 0 # cr13: home space segment table + .long 0xc0000000 # cr14: machine check handling off + .long 0 # cr15: linkage stack operations +.Lpcmem:.long 0x00080000,0x80000000 + .Lchkmem +.Lpcfpu:.long 0x00080000,0x80000000 + .Lchkfpu +.Lpccsp:.long 0x00080000,0x80000000 + .Lchkcsp +.Lpcmvpg:.long 0x00080000,0x80000000 + .Lchkmvpg +.Lpcidte:.long 0x00080000,0x80000000 + .Lchkidte +.Lmemsize:.long memory_size +.Lmchunk:.long memory_chunk +.Lmflags:.long machine_flags +.Lbss_bgn: .long __bss_start +.Lbss_end: .long _end + + .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: + .long 0,0 # IPL_DEVICE + .long 0,RAMDISK_ORIGIN # INITRD_START + .long 0,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 +# + l %r15,.Linittu-.LPG3(%r13) + mvc __LC_CURRENT(4),__TI_task(%r15) + ahi %r15,1<<(PAGE_SHIFT+THREAD_ORDER) # init_task_union+THREAD_SIZE + st %r15,__LC_KERNEL_STACK # set end of kernel stack + ahi %r15,-96 + xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) # clear backchain + +# check control registers + stctl %c0,%c15,0(%r15) + oi 2(%r15),0x40 # enable sigp emergency signal + oi 0(%r15),0x10 # switch on low address protection + lctl %c0,%c15,0(%r15) + +# + lam 0,15,.Laregs-.LPG3(%r13) # load access regs needed by uaccess + l %r14,.Lstart-.LPG3(%r13) + basr %r14,%r14 # call start_kernel +# +# We returned from start_kernel ?!? PANIK +# + basr %r13,0 + lpsw .Ldw-.(%r13) # load disabled wait psw +# + .align 8 +.Ldw: .long 0x000a0000,0x00000000 +.Linittu:.long init_thread_union +.Lstart:.long start_kernel +.Laregs:.long 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 |
