arch/s390/kernel/head64.S

   1 /*
   2  * arch/s390/kernel/head64.S
   3  *
   4  * Copyright (C) IBM Corp. 1999,2006
   5  *
   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>
  10  *
  11  */
  12
  13         .org    0x11000
  14
  15 startup_continue:
  16         basr    %r13,0                  # get base
  17 .LPG1:  sll     %r13,1                  # remove high order bit
  18         srl     %r13,1
  19
  20 #ifdef CONFIG_ZFCPDUMP
  21
  22         # check if we have been ipled using zfcp dump:
  23
  24         tm      0xb9,0x01               # test if subchannel is enabled
  25         jno     .nodump                 # subchannel disabled
  26         l       %r1,0xb8
  27         la      %r5,.Lipl_schib-.LPG1(%r13)
  28         stsch   0(%r5)                  # get schib of subchannel
  29         jne     .nodump                 # schib not available
  30         tm      5(%r5),0x01             # devno valid?
  31         jno     .nodump
  32         tm      4(%r5),0x80             # qdio capable device?
  33         jno     .nodump
  34         l       %r2,20(%r0)             # address of ipl parameter block
  35         lhi     %r3,0
  36         ic      %r3,0x148(%r2)          # get opt field
  37         chi     %r3,0x20                # load with dump?
  38         jne     .nodump
  39
  40         # store all prefix registers in case of load with dump:
  41
  42         la      %r7,0                   # base register for 0 page
  43         la      %r8,0                   # first cpu
  44         l       %r11,.Lpref_arr_ptr-.LPG1(%r13) # address of prefix array
  45         ahi     %r11,4                  # skip boot cpu
  46         lr      %r12,%r11
  47         ahi     %r12,(CONFIG_NR_CPUS*4) # end of prefix array
  48         stap    .Lcurrent_cpu+2-.LPG1(%r13)     # store current cpu addr
  49 1:
  50         cl      %r8,.Lcurrent_cpu-.LPG1(%r13)   # is ipl cpu ?
  51         je      4f                              # if yes get next cpu
  52 2:
  53         lr      %r9,%r7
  54         sigp    %r9,%r8,0x9             # stop & store status of cpu
  55         brc     8,3f                    # accepted
  56         brc     4,4f                    # status stored: next cpu
  57         brc     2,2b                    # busy:          try again
  58         brc     1,4f                    # not op:        next cpu
  59 3:
  60         mvc     0(4,%r11),264(%r7)      # copy prefix register to prefix array
  61         ahi     %r11,4                  # next element in prefix array
  62         clr     %r11,%r12
  63         je      5f                      # no more space in prefix array
  64 4:
  65         ahi     %r8,1                           # next cpu (r8 += 1)
  66         cl      %r8,.Llast_cpu-.LPG1(%r13)      # is last possible cpu ?
  67         jl      1b                              # jump if not last cpu
  68 5:
  69         lhi     %r1,2                   # mode 2 = esame (dump)
  70         j       6f
  71         .align 4
  72 .Lipl_schib:
  73         .rept 13
  74         .long 0
  75         .endr
  76 .nodump:
  77         lhi     %r1,1                   # mode 1 = esame (normal ipl)
  78 6:
  79 #else
  80         lhi     %r1,1                   # mode 1 = esame (normal ipl)
  81 #endif /* CONFIG_ZFCPDUMP */
  82         mvi     __LC_AR_MODE_ID,1       # set esame flag
  83         slr     %r0,%r0                 # set cpuid to zero
  84         sigp    %r1,%r0,0x12            # switch to esame mode
  85         sam64                           # switch to 64 bit mode
  86         lctlg   %c0,%c15,.Lctl-.LPG1(%r13)      # load control registers
  87         lg      %r12,.Lparmaddr-.LPG1(%r13)     # pointer to parameter area
  88                                         # move IPL device to lowcore
  89         lghi    %r0,__LC_PASTE
  90         stg     %r0,__LC_VDSO_PER_CPU
  91 #
  92 # Setup stack
  93 #
  94         larl    %r15,init_thread_union
  95         lg      %r14,__TI_task(%r15)    # cache current in lowcore
  96         stg     %r14,__LC_CURRENT
  97         aghi    %r15,1<<(PAGE_SHIFT+THREAD_ORDER) # init_task_union + THREAD_SIZE
  98         stg     %r15,__LC_KERNEL_STACK  # set end of kernel stack
  99         aghi    %r15,-160
 100 #
 101 # Save ipl parameters, clear bss memory, initialize storage key for kernel pages,
 102 # and create a kernel NSS if the SAVESYS= parm is defined
 103 #
 104         brasl   %r14,startup_init
 105         lpswe   .Lentry-.LPG1(13)       # jump to _stext in primary-space,
 106                                         # virtual and never return ...
 107         .align  16
 108 .Lentry:.quad   0x0000000180000000,_stext
 109 .Lctl:  .quad   0x04350002              # cr0: various things
 110         .quad   0                       # cr1: primary space segment table
 111         .quad   .Lduct                  # cr2: dispatchable unit control table
 112         .quad   0                       # cr3: instruction authorization
 113         .quad   0                       # cr4: instruction authorization
 114         .quad   .Lduct                  # cr5: primary-aste origin
 115         .quad   0                       # cr6:  I/O interrupts
 116         .quad   0                       # cr7:  secondary space segment table
 117         .quad   0                       # cr8:  access registers translation
 118         .quad   0                       # cr9:  tracing off
 119         .quad   0                       # cr10: tracing off
 120         .quad   0                       # cr11: tracing off
 121         .quad   0                       # cr12: tracing off
 122         .quad   0                       # cr13: home space segment table
 123         .quad   0xc0000000              # cr14: machine check handling off
 124         .quad   0                       # cr15: linkage stack operations
 125 .Lpcmsk:.quad   0x0000000180000000
 126 .L4malign:.quad 0xffffffffffc00000
 127 .Lscan2g:.quad  0x80000000 + 0x20000 - 8        # 2GB + 128K - 8
 128 .Lnop:  .long   0x07000700
 129 #ifdef CONFIG_ZFCPDUMP
 130 .Lcurrent_cpu:
 131         .long 0x0
 132 .Llast_cpu:
 133         .long 0x0000ffff
 134 .Lpref_arr_ptr:
 135         .long zfcpdump_prefix_array
 136 #endif /* CONFIG_ZFCPDUMP */
 137 .Lparmaddr:
 138         .quad   PARMAREA
 139         .align  64
 140 .Lduct: .long   0,0,0,0,.Lduald,0,0,0
 141         .long   0,0,0,0,0,0,0,0
 142         .align  128
 143 .Lduald:.rept   8
 144         .long   0x80000000,0,0,0        # invalid access-list entries
 145         .endr
 146
 147         .org    0x12000
 148         .globl  _ehead
 149 _ehead:
 150 #ifdef CONFIG_SHARED_KERNEL
 151         .org    0x100000
 152 #endif
 153
 154 #
 155 # startup-code, running in absolute addressing mode
 156 #
 157         .globl  _stext
 158 _stext: basr    %r13,0                  # get base
 159 .LPG3:
 160 # check control registers
 161         stctg   %c0,%c15,0(%r15)
 162         oi      6(%r15),0x40            # enable sigp emergency signal
 163         oi      4(%r15),0x10            # switch on low address proctection
 164         lctlg   %c0,%c15,0(%r15)
 165
 166         lam     0,15,.Laregs-.LPG3(%r13)        # load acrs needed by uaccess
 167         brasl   %r14,start_kernel       # go to C code
 168 #
 169 # We returned from start_kernel ?!? PANIK
 170 #
 171         basr    %r13,0
 172         lpswe   .Ldw-.(%r13)            # load disabled wait psw
 173
 174         .align  8
 175 .Ldw:   .quad   0x0002000180000000,0x0000000000000000
 176 .Laregs:.long   0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0