arch/s390/kernel/head64.S

   1 /*
   2  * Copyright IBM Corp. 1999, 2010
   3  *
   4  *   Author(s): Hartmut Penner <hp@de.ibm.com>
   5  *              Martin Schwidefsky <schwidefsky@de.ibm.com>
   6  *              Rob van der Heij <rvdhei@iae.nl>
   7  *              Heiko Carstens <heiko.carstens@de.ibm.com>
   8  *
   9  */
  10
  11 #include <linux/init.h>
  12 #include <linux/linkage.h>
  13 #include <asm/asm-offsets.h>
  14 #include <asm/thread_info.h>
  15 #include <asm/page.h>
  16
  17 __HEAD
  18 ENTRY(startup_continue)
  19         larl    %r1,sched_clock_base_cc
  20         mvc     0(8,%r1),__LC_LAST_UPDATE_CLOCK
  21         larl    %r13,.LPG1              # get base
  22         lctlg   %c0,%c15,.Lctl-.LPG1(%r13)      # load control registers
  23         lg      %r12,.Lparmaddr-.LPG1(%r13)     # pointer to parameter area
  24                                         # move IPL device to lowcore
  25         lghi    %r0,__LC_PASTE
  26         stg     %r0,__LC_VDSO_PER_CPU
  27 #
  28 # Setup stack
  29 #
  30         larl    %r15,init_thread_union
  31         stg     %r15,__LC_THREAD_INFO   # cache thread info in lowcore
  32         lg      %r14,__TI_task(%r15)    # cache current in lowcore
  33         stg     %r14,__LC_CURRENT
  34         aghi    %r15,1<<(PAGE_SHIFT+THREAD_ORDER) # init_task_union + THREAD_SIZE
  35         stg     %r15,__LC_KERNEL_STACK  # set end of kernel stack
  36         aghi    %r15,-160
  37 #
  38 # Save ipl parameters, clear bss memory, initialize storage key for kernel pages,
  39 # and create a kernel NSS if the SAVESYS= parm is defined
  40 #
  41         brasl   %r14,startup_init
  42         lpswe   .Lentry-.LPG1(13)       # jump to _stext in primary-space,
  43                                         # virtual and never return ...
  44         .align  16
  45 .LPG1:
  46 .Lentry:.quad   0x0000000180000000,_stext
  47 .Lctl:  .quad   0x04040000              # cr0: AFP registers & secondary space
  48         .quad   0                       # cr1: primary space segment table
  49         .quad   .Lduct                  # cr2: dispatchable unit control table
  50         .quad   0                       # cr3: instruction authorization
  51         .quad   0                       # cr4: instruction authorization
  52         .quad   .Lduct                  # cr5: primary-aste origin
  53         .quad   0                       # cr6:  I/O interrupts
  54         .quad   0                       # cr7:  secondary space segment table
  55         .quad   0                       # cr8:  access registers translation
  56         .quad   0                       # cr9:  tracing off
  57         .quad   0                       # cr10: tracing off
  58         .quad   0                       # cr11: tracing off
  59         .quad   0                       # cr12: tracing off
  60         .quad   0                       # cr13: home space segment table
  61         .quad   0xc0000000              # cr14: machine check handling off
  62         .quad   0                       # cr15: linkage stack operations
  63 .Lpcmsk:.quad   0x0000000180000000
  64 .L4malign:.quad 0xffffffffffc00000
  65 .Lscan2g:.quad  0x80000000 + 0x20000 - 8        # 2GB + 128K - 8
  66 .Lnop:  .long   0x07000700
  67 .Lparmaddr:
  68         .quad   PARMAREA
  69         .align  64
  70 .Lduct: .long   0,0,0,0,.Lduald,0,0,0
  71         .long   0,0,0,0,0,0,0,0
  72         .align  128
  73 .Lduald:.rept   8
  74         .long   0x80000000,0,0,0        # invalid access-list entries
  75         .endr
  76
  77 ENTRY(_ehead)
  78
  79         .org    0x100000 - 0x11000      # head.o ends at 0x11000
  80 #
  81 # startup-code, running in absolute addressing mode
  82 #
  83 ENTRY(_stext)
  84         basr    %r13,0                  # get base
  85 .LPG3:
  86 # check control registers
  87         stctg   %c0,%c15,0(%r15)
  88         oi      6(%r15),0x60            # enable sigp emergency & external call
  89         oi      4(%r15),0x10            # switch on low address proctection
  90         lctlg   %c0,%c15,0(%r15)
  91
  92         lam     0,15,.Laregs-.LPG3(%r13)        # load acrs needed by uaccess
  93         brasl   %r14,start_kernel       # go to C code
  94 #
  95 # We returned from start_kernel ?!? PANIK
  96 #
  97         basr    %r13,0
  98         lpswe   .Ldw-.(%r13)            # load disabled wait psw
  99
 100         .align  8
 101 .Ldw:   .quad   0x0002000180000000,0x0000000000000000
 102 .Laregs:.long   0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0