| /* |
| * arch/s390/kernel/head31.S |
| * |
| * Copyright (C) IBM Corp. 2005,2006 |
| * |
| * 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 |
| .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,RAMDISK_ORIGIN # INITRD_START |
| .long 0,RAMDISK_SIZE # 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 |
| .align 4096 |
| .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 |
| .align 4096 |
| |
| #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 |