/* * arch/s390/kernel/head31.S * * Copyright (C) IBM Corp. 2005,2006 * * Author(s): Hartmut Penner * Martin Schwidefsky * Rob van der Heij * Heiko Carstens * */ # # 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 .LPG0: l %r13,0f-.LPG0(%r13) b 0(%r13) 0: .long startup_continue # # params at 10400 (setup.h) # .org PARMAREA .long 0,0 # IPL_DEVICE .long 0,0 # INITRD_START .long 0,0 # INITRD_SIZE .org COMMAND_LINE .byte "root=/dev/ram0 ro" .byte 0 .org 0x11000 startup_continue: basr %r13,0 # get base .LPG1: GET_IPL_DEVICE lctl %c0,%c15,.Lctl-.LPG1(%r13) # load control registers l %r12,.Lparmaddr-.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 l %r4,.Lsccbaddr-.LPG1(%r13) # %r4 is our index for sccb stuff lr %r1,%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-.Lsccb(%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-.Lsccb(%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-.Lsccb(%r4) chi %r3,0x00 jne .Lcompmem l %r3,.Lscpa2-.Lsccb(%r4) .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 .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 .Lduct: .long 0,0,0,0,0,0,0,0 .long 0,0,0,0,0,0,0,0 .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 .Lparmaddr: .long PARMAREA .Lsccbaddr: .long .Lsccb .org 0x12000 .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 0x13000 #ifdef CONFIG_SHARED_KERNEL .org 0x100000 #endif # # startup-code, running in absolute addressing 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