arch/s390/kernel/head.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  * There are 5 different IPL methods
  10  *  1) load the image directly into ram at address 0 and do an PSW restart
  11  *  2) linload will load the image from address 0x10000 to memory 0x10000
  12  *     and start the code thru LPSW 0x0008000080010000 (VM only, deprecated)
  13  *  3) generate the tape ipl header, store the generated image on a tape
  14  *     and ipl from it
  15  *     In case of SL tape you need to IPL 5 times to get past VOL1 etc
  16  *  4) generate the vm reader ipl header, move the generated image to the
  17  *     VM reader (use option NOH!) and do a ipl from reader (VM only)
  18  *  5) direct call of start by the SALIPL loader
  19  *  We use the cpuid to distinguish between VM and native ipl
  20  *  params for kernel are pushed to 0x10400 (see setup.h)
  21  *
  22  */
  23
  24 #include <linux/init.h>
  25 #include <linux/linkage.h>
  26 #include <asm/asm-offsets.h>
  27 #include <asm/thread_info.h>
  28 #include <asm/page.h>
  29
  30 #define ARCH_OFFSET     4
  31
  32 __HEAD
  33
  34 #define IPL_BS  0x730
  35         .org    0
  36         .long   0x00080000,0x80000000+iplstart  # The first 24 bytes are loaded
  37         .long   0x02000018,0x60000050           # by ipl to addresses 0-23.
  38         .long   0x02000068,0x60000050           # (a PSW and two CCWs).
  39         .fill   80-24,1,0x40                    # bytes 24-79 are discarded !!
  40         .long   0x020000f0,0x60000050           # The next 160 byte are loaded
  41         .long   0x02000140,0x60000050           # to addresses 0x18-0xb7
  42         .long   0x02000190,0x60000050           # They form the continuation
  43         .long   0x020001e0,0x60000050           # of the CCW program started
  44         .long   0x02000230,0x60000050           # by ipl and load the range
  45         .long   0x02000280,0x60000050           # 0x0f0-0x730 from the image
  46         .long   0x020002d0,0x60000050           # to the range 0x0f0-0x730
  47         .long   0x02000320,0x60000050           # in memory. At the end of
  48         .long   0x02000370,0x60000050           # the channel program the PSW
  49         .long   0x020003c0,0x60000050           # at location 0 is loaded.
  50         .long   0x02000410,0x60000050           # Initial processing starts
  51         .long   0x02000460,0x60000050           # at 0x200 = iplstart.
  52         .long   0x020004b0,0x60000050
  53         .long   0x02000500,0x60000050
  54         .long   0x02000550,0x60000050
  55         .long   0x020005a0,0x60000050
  56         .long   0x020005f0,0x60000050
  57         .long   0x02000640,0x60000050
  58         .long   0x02000690,0x60000050
  59         .long   0x020006e0,0x20000050
  60
  61         .org    0x200
  62 #
  63 # subroutine to set architecture mode
  64 #
  65 .Lsetmode:
  66         mvi     __LC_AR_MODE_ID,1       # set esame flag
  67         slr     %r0,%r0                 # set cpuid to zero
  68         lhi     %r1,2                   # mode 2 = esame (dump)
  69         sigp    %r1,%r0,0x12            # switch to esame mode
  70         bras    %r13,0f
  71         .fill   16,4,0x0
  72 0:      lmh     %r0,%r15,0(%r13)        # clear high-order half of gprs
  73         sam31                           # switch to 31 bit addressing mode
  74         br      %r14
  75
  76 #
  77 # subroutine to wait for end I/O
  78 #
  79 .Lirqwait:
  80         mvc     0x1f0(16),.Lnewpsw      # set up IO interrupt psw
  81         lpsw    .Lwaitpsw
  82 .Lioint:
  83         br      %r14
  84         .align  8
  85 .Lnewpsw:
  86         .quad   0x0000000080000000,.Lioint
  87 .Lwaitpsw:
  88         .long   0x020a0000,0x80000000+.Lioint
  89
  90 #
  91 # subroutine for loading cards from the reader
  92 #
  93 .Lloader:
  94         la      %r4,0(%r14)
  95         la      %r3,.Lorb               # r2 = address of orb into r2
  96         la      %r5,.Lirb               # r4 = address of irb
  97         la      %r6,.Lccws
  98         la      %r7,20
  99 .Linit:
 100         st      %r2,4(%r6)              # initialize CCW data addresses
 101         la      %r2,0x50(%r2)
 102         la      %r6,8(%r6)
 103         bct     7,.Linit
 104
 105         lctl    %c6,%c6,.Lcr6           # set IO subclass mask
 106         slr     %r2,%r2
 107 .Lldlp:
 108         ssch    0(%r3)                  # load chunk of 1600 bytes
 109         bnz     .Llderr
 110 .Lwait4irq:
 111         bas     %r14,.Lirqwait
 112         c       %r1,0xb8                # compare subchannel number
 113         bne     .Lwait4irq
 114         tsch    0(%r5)
 115
 116         slr     %r0,%r0
 117         ic      %r0,8(%r5)              # get device status
 118         chi     %r0,8                   # channel end ?
 119         be      .Lcont
 120         chi     %r0,12                  # channel end + device end ?
 121         be      .Lcont
 122
 123         l       %r0,4(%r5)
 124         s       %r0,8(%r3)              # r0/8 = number of ccws executed
 125         mhi     %r0,10                  # *10 = number of bytes in ccws
 126         lh      %r3,10(%r5)             # get residual count
 127         sr      %r0,%r3                 # #ccws*80-residual=#bytes read
 128         ar      %r2,%r0
 129
 130         br      %r4                     # r2 contains the total size
 131
 132 .Lcont:
 133         ahi     %r2,0x640               # add 0x640 to total size
 134         la      %r6,.Lccws
 135         la      %r7,20
 136 .Lincr:
 137         l       %r0,4(%r6)              # update CCW data addresses
 138         ahi     %r0,0x640
 139         st      %r0,4(%r6)
 140         ahi     %r6,8
 141         bct     7,.Lincr
 142
 143         b       .Lldlp
 144 .Llderr:
 145         lpsw    .Lcrash
 146
 147         .align  8
 148 .Lorb:  .long   0x00000000,0x0080ff00,.Lccws
 149 .Lirb:  .long   0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
 150 .Lcr6:  .long   0xff000000
 151 .Lloadp:.long   0,0
 152         .align  8
 153 .Lcrash:.long   0x000a0000,0x00000000
 154
 155         .align  8
 156 .Lccws: .rept   19
 157         .long   0x02600050,0x00000000
 158         .endr
 159         .long   0x02200050,0x00000000
 160
 161 iplstart:
 162         bas     %r14,.Lsetmode          # Immediately switch to 64 bit mode
 163         lh      %r1,0xb8                # test if subchannel number
 164         bct     %r1,.Lnoload            #  is valid
 165         l       %r1,0xb8                # load ipl subchannel number
 166         la      %r2,IPL_BS              # load start address
 167         bas     %r14,.Lloader           # load rest of ipl image
 168         l       %r12,.Lparm             # pointer to parameter area
 169         st      %r1,IPL_DEVICE+ARCH_OFFSET-PARMAREA(%r12) # save ipl device number
 170
 171 #
 172 # load parameter file from ipl device
 173 #
 174 .Lagain1:
 175         l       %r2,.Linitrd            # ramdisk loc. is temp
 176         bas     %r14,.Lloader           # load parameter file
 177         ltr     %r2,%r2                 # got anything ?
 178         bz      .Lnopf
 179         chi     %r2,895
 180         bnh     .Lnotrunc
 181         la      %r2,895
 182 .Lnotrunc:
 183         l       %r4,.Linitrd
 184         clc     0(3,%r4),.L_hdr         # if it is HDRx
 185         bz      .Lagain1                # skip dataset header
 186         clc     0(3,%r4),.L_eof         # if it is EOFx
 187         bz      .Lagain1                # skip dateset trailer
 188         la      %r5,0(%r4,%r2)
 189         lr      %r3,%r2
 190         la      %r3,COMMAND_LINE-PARMAREA(%r12) # load adr. of command line
 191         mvc     0(256,%r3),0(%r4)
 192         mvc     256(256,%r3),256(%r4)
 193         mvc     512(256,%r3),512(%r4)
 194         mvc     768(122,%r3),768(%r4)
 195         slr     %r0,%r0
 196         b       .Lcntlp
 197 .Ldelspc:
 198         ic      %r0,0(%r2,%r3)
 199         chi     %r0,0x20                # is it a space ?
 200         be      .Lcntlp
 201         ahi     %r2,1
 202         b       .Leolp
 203 .Lcntlp:
 204         brct    %r2,.Ldelspc
 205 .Leolp:
 206         slr     %r0,%r0
 207         stc     %r0,0(%r2,%r3)          # terminate buffer
 208 .Lnopf:
 209
 210 #
 211 # load ramdisk from ipl device
 212 #
 213 .Lagain2:
 214         l       %r2,.Linitrd            # addr of ramdisk
 215         st      %r2,INITRD_START+ARCH_OFFSET-PARMAREA(%r12)
 216         bas     %r14,.Lloader           # load ramdisk
 217         st      %r2,INITRD_SIZE+ARCH_OFFSET-PARMAREA(%r12) # store size of rd
 218         ltr     %r2,%r2
 219         bnz     .Lrdcont
 220         st      %r2,INITRD_START+ARCH_OFFSET-PARMAREA(%r12) # no ramdisk found
 221 .Lrdcont:
 222         l       %r2,.Linitrd
 223
 224         clc     0(3,%r2),.L_hdr         # skip HDRx and EOFx
 225         bz      .Lagain2
 226         clc     0(3,%r2),.L_eof
 227         bz      .Lagain2
 228
 229 #
 230 # reset files in VM reader
 231 #
 232         stidp   .Lcpuid                 # store cpuid
 233         tm      .Lcpuid,0xff            # running VM ?
 234         bno     .Lnoreset
 235         la      %r2,.Lreset
 236         lhi     %r3,26
 237         diag    %r2,%r3,8
 238         la      %r5,.Lirb
 239         stsch   0(%r5)                  # check if irq is pending
 240         tm      30(%r5),0x0f            # by verifying if any of the
 241         bnz     .Lwaitforirq            # activity or status control
 242         tm      31(%r5),0xff            # bits is set in the schib
 243         bz      .Lnoreset
 244 .Lwaitforirq:
 245         bas     %r14,.Lirqwait          # wait for IO interrupt
 246         c       %r1,0xb8                # compare subchannel number
 247         bne     .Lwaitforirq
 248         la      %r5,.Lirb
 249         tsch    0(%r5)
 250 .Lnoreset:
 251         b       .Lnoload
 252
 253 #
 254 # everything loaded, go for it
 255 #
 256 .Lnoload:
 257         l       %r1,.Lstartup
 258         br      %r1
 259
 260 .Linitrd:.long _end                     # default address of initrd
 261 .Lparm: .long  PARMAREA
 262 .Lstartup: .long startup
 263 .Lreset:.byte   0xc3,0xc8,0xc1,0xd5,0xc7,0xc5,0x40,0xd9,0xc4,0xd9,0x40
 264         .byte   0xc1,0xd3,0xd3,0x40,0xd2,0xc5,0xc5,0xd7,0x40,0xd5,0xd6
 265         .byte   0xc8,0xd6,0xd3,0xc4     # "change rdr all keep nohold"
 266 .L_eof: .long   0xc5d6c600       /* C'EOF' */
 267 .L_hdr: .long   0xc8c4d900       /* C'HDR' */
 268         .align  8
 269 .Lcpuid:.fill   8,1,0
 270
 271 #
 272 # SALIPL loader support. Based on a patch by Rob van der Heij.
 273 # This entry point is called directly from the SALIPL loader and
 274 # doesn't need a builtin ipl record.
 275 #
 276         .org    0x800
 277 ENTRY(start)
 278         stm     %r0,%r15,0x07b0         # store registers
 279         bas     %r14,.Lsetmode          # Immediately switch to 64 bit mode
 280         basr    %r12,%r0
 281 .base:
 282         l       %r11,.parm
 283         l       %r8,.cmd                # pointer to command buffer
 284
 285         ltr     %r9,%r9                 # do we have SALIPL parameters?
 286         bp      .sk8x8
 287
 288         mvc     0(64,%r8),0x00b0        # copy saved registers
 289         xc      64(240-64,%r8),0(%r8)   # remainder of buffer
 290         tr      0(64,%r8),.lowcase
 291         b       .gotr
 292 .sk8x8:
 293         mvc     0(240,%r8),0(%r9)       # copy iplparms into buffer
 294 .gotr:
 295         slr     %r0,%r0
 296         st      %r0,INITRD_SIZE+ARCH_OFFSET-PARMAREA(%r11)
 297         st      %r0,INITRD_START+ARCH_OFFSET-PARMAREA(%r11)
 298         j       startup                 # continue with startup
 299 .cmd:   .long   COMMAND_LINE            # address of command line buffer
 300 .parm:  .long   PARMAREA
 301 .lowcase:
 302         .byte 0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07
 303         .byte 0x08,0x09,0x0a,0x0b,0x0c,0x0d,0x0e,0x0f
 304         .byte 0x10,0x11,0x12,0x13,0x14,0x15,0x16,0x17
 305         .byte 0x18,0x19,0x1a,0x1b,0x1c,0x1d,0x1e,0x1f
 306         .byte 0x20,0x21,0x22,0x23,0x24,0x25,0x26,0x27
 307         .byte 0x28,0x29,0x2a,0x2b,0x2c,0x2d,0x2e,0x2f
 308         .byte 0x30,0x31,0x32,0x33,0x34,0x35,0x36,0x37
 309         .byte 0x38,0x39,0x3a,0x3b,0x3c,0x3d,0x3e,0x3f
 310         .byte 0x40,0x41,0x42,0x43,0x44,0x45,0x46,0x47
 311         .byte 0x48,0x49,0x4a,0x4b,0x4c,0x4d,0x4e,0x4f
 312         .byte 0x50,0x51,0x52,0x53,0x54,0x55,0x56,0x57
 313         .byte 0x58,0x59,0x5a,0x5b,0x5c,0x5d,0x5e,0x5f
 314         .byte 0x60,0x61,0x62,0x63,0x64,0x65,0x66,0x67
 315         .byte 0x68,0x69,0x6a,0x6b,0x6c,0x6d,0x6e,0x6f
 316         .byte 0x70,0x71,0x72,0x73,0x74,0x75,0x76,0x77
 317         .byte 0x78,0x79,0x7a,0x7b,0x7c,0x7d,0x7e,0x7f
 318
 319         .byte 0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87
 320         .byte 0x88,0x89,0x8a,0x8b,0x8c,0x8d,0x8e,0x8f
 321         .byte 0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97
 322         .byte 0x98,0x99,0x9a,0x9b,0x9c,0x9d,0x9e,0x9f
 323         .byte 0xa0,0xa1,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7
 324         .byte 0xa8,0xa9,0xaa,0xab,0xac,0xad,0xae,0xaf
 325         .byte 0xb0,0xb1,0xb2,0xb3,0xb4,0xb5,0xb6,0xb7
 326         .byte 0xb8,0xb9,0xba,0xbb,0xbc,0xbd,0xbe,0xbf
 327         .byte 0xc0,0x81,0x82,0x83,0x84,0x85,0x86,0x87   # .abcdefg
 328         .byte 0x88,0x89,0xca,0xcb,0xcc,0xcd,0xce,0xcf   # hi
 329         .byte 0xd0,0x91,0x92,0x93,0x94,0x95,0x96,0x97   # .jklmnop
 330         .byte 0x98,0x99,0xda,0xdb,0xdc,0xdd,0xde,0xdf   # qr
 331         .byte 0xe0,0xe1,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7   # ..stuvwx
 332         .byte 0xa8,0xa9,0xea,0xeb,0xec,0xed,0xee,0xef   # yz
 333         .byte 0xf0,0xf1,0xf2,0xf3,0xf4,0xf5,0xf6,0xf7
 334         .byte 0xf8,0xf9,0xfa,0xfb,0xfc,0xfd,0xfe,0xff
 335
 336 #
 337 # startup-code at 0x10000, running in absolute addressing mode
 338 # this is called either by the ipl loader or directly by PSW restart
 339 # or linload or SALIPL
 340 #
 341         .org    0x10000
 342 ENTRY(startup)
 343         j       .Lep_startup_normal
 344         .org    0x10008
 345 #
 346 # This is a list of s390 kernel entry points. At address 0x1000f the number of
 347 # valid entry points is stored.
 348 #
 349 # IMPORTANT: Do not change this table, it is s390 kernel ABI!
 350 #
 351         .ascii  "S390EP"
 352         .byte   0x00,0x01
 353 #
 354 # kdump startup-code at 0x10010, running in 64 bit absolute addressing mode
 355 #
 356         .org    0x10010
 357 ENTRY(startup_kdump)
 358         j       .Lep_startup_kdump
 359 .Lep_startup_normal:
 360         mvi     __LC_AR_MODE_ID,1       # set esame flag
 361         slr     %r0,%r0                 # set cpuid to zero
 362         lhi     %r1,2                   # mode 2 = esame (dump)
 363         sigp    %r1,%r0,0x12            # switch to esame mode
 364         bras    %r13,0f
 365         .fill   16,4,0x0
 366 0:      lmh     %r0,%r15,0(%r13)        # clear high-order half of gprs
 367         sam31                           # switch to 31 bit addressing mode
 368         basr    %r13,0                  # get base
 369 .LPG0:
 370         xc      0x200(256),0x200        # partially clear lowcore
 371         xc      0x300(256),0x300
 372         xc      0xe00(256),0xe00
 373         lctlg   %c0,%c15,0x200(%r0)     # initialize control registers
 374         stck    __LC_LAST_UPDATE_CLOCK
 375         spt     6f-.LPG0(%r13)
 376         mvc     __LC_LAST_UPDATE_TIMER(8),6f-.LPG0(%r13)
 377         xc      __LC_STFL_FAC_LIST(8),__LC_STFL_FAC_LIST
 378         # check capabilities against MARCH_{G5,Z900,Z990,Z9_109,Z10}
 379         .insn   s,0xb2b10000,0          # store facilities @ __LC_STFL_FAC_LIST
 380         tm      __LC_STFL_FAC_LIST,0x01 # stfle available ?
 381         jz      0f
 382         la      %r0,1
 383         .insn   s,0xb2b00000,__LC_STFL_FAC_LIST # store facility list extended
 384         # verify if all required facilities are supported by the machine
 385 0:      la      %r1,__LC_STFL_FAC_LIST
 386         la      %r2,3f+8-.LPG0(%r13)
 387         l       %r3,0(%r2)
 388 1:      l       %r0,0(%r1)
 389         n       %r0,4(%r2)
 390         cl      %r0,4(%r2)
 391         jne     2f
 392         la      %r1,4(%r1)
 393         la      %r2,4(%r2)
 394         ahi     %r3,-1
 395         jnz     1b
 396         j       4f
 397 2:      l       %r15,.Lstack-.LPG0(%r13)
 398         ahi     %r15,-96
 399         la      %r2,.Lals_string-.LPG0(%r13)
 400         l       %r3,.Lsclp_print-.LPG0(%r13)
 401         basr    %r14,%r3
 402         lpsw    3f-.LPG0(%r13)          # machine type not good enough, crash
 403 .Lals_string:
 404         .asciz  "The Linux kernel requires more recent processor hardware"
 405 .Lsclp_print:
 406         .long   _sclp_print_early
 407 .Lstack:
 408         .long   0x8000 + (1<<(PAGE_SHIFT+THREAD_ORDER))
 409         .align 16
 410 3:      .long   0x000a0000,0x8badcccc
 411
 412 # List of facilities that are required. If not all facilities are present
 413 # the kernel will crash. Format is number of facility words with bits set,
 414 # followed by the facility words.
 415
 416 #if defined(CONFIG_MARCH_Z13)
 417         .long 2, 0xc100eff2, 0xf46cc800
 418 #elif defined(CONFIG_MARCH_ZEC12)
 419         .long 2, 0xc100eff2, 0xf46cc800
 420 #elif defined(CONFIG_MARCH_Z196)
 421         .long 2, 0xc100eff2, 0xf46c0000
 422 #elif defined(CONFIG_MARCH_Z10)
 423         .long 2, 0xc100eff2, 0xf0680000
 424 #elif defined(CONFIG_MARCH_Z9_109)
 425         .long 1, 0xc100efc2
 426 #elif defined(CONFIG_MARCH_Z990)
 427         .long 1, 0xc0002000
 428 #elif defined(CONFIG_MARCH_Z900)
 429         .long 1, 0xc0000000
 430 #endif
 431 4:
 432         /* Continue with 64bit startup code in head64.S */
 433         sam64                           # switch to 64 bit mode
 434         jg      startup_continue
 435
 436         .align  8
 437 6:      .long   0x7fffffff,0xffffffff
 438
 439 #include "head_kdump.S"
 440
 441 #
 442 # params at 10400 (setup.h)
 443 #
 444         .org    PARMAREA
 445         .long   0,0                     # IPL_DEVICE
 446         .long   0,0                     # INITRD_START
 447         .long   0,0                     # INITRD_SIZE
 448         .long   0,0                     # OLDMEM_BASE
 449         .long   0,0                     # OLDMEM_SIZE
 450
 451         .org    COMMAND_LINE
 452         .byte   "root=/dev/ram0 ro"
 453         .byte   0
 454
 455         .org    0x11000