arch/s390/kernel/sclp.S

   1 /*
   2  * Mini SCLP driver.
   3  *
   4  * Copyright IBM Corp. 2004,2009
   5  *
   6  *   Author(s): Peter Oberparleiter <Peter.Oberparleiter@de.ibm.com>,
   7  *              Heiko Carstens <heiko.carstens@de.ibm.com>,
   8  *
   9  */
  10
  11 #include <linux/linkage.h>
  12
  13 LC_EXT_NEW_PSW          = 0x58                  # addr of ext int handler
  14 LC_EXT_NEW_PSW_64       = 0x1b0                 # addr of ext int handler 64 bit
  15 LC_EXT_INT_PARAM        = 0x80                  # addr of ext int parameter
  16 LC_EXT_INT_CODE         = 0x86                  # addr of ext int code
  17 LC_AR_MODE_ID           = 0xa3
  18
  19 #
  20 # Subroutine which waits synchronously until either an external interruption
  21 # or a timeout occurs.
  22 #
  23 # Parameters:
  24 #   R2  = 0 for no timeout, non-zero for timeout in (approximated) seconds
  25 #
  26 # Returns:
  27 #   R2  = 0 on interrupt, 2 on timeout
  28 #   R3  = external interruption parameter if R2=0
  29 #
  30
  31 _sclp_wait_int:
  32         stm     %r6,%r15,24(%r15)               # save registers
  33         basr    %r13,0                          # get base register
  34 .LbaseS1:
  35         ahi     %r15,-96                        # create stack frame
  36         la      %r8,LC_EXT_NEW_PSW              # register int handler
  37         la      %r9,.LextpswS1-.LbaseS1(%r13)
  38 #ifdef CONFIG_64BIT
  39         tm      LC_AR_MODE_ID,1
  40         jno     .Lesa1
  41         la      %r8,LC_EXT_NEW_PSW_64           # register int handler 64 bit
  42         la      %r9,.LextpswS1_64-.LbaseS1(%r13)
  43 .Lesa1:
  44 #endif
  45         mvc     .LoldpswS1-.LbaseS1(16,%r13),0(%r8)
  46         mvc     0(16,%r8),0(%r9)
  47         lhi     %r6,0x0200                      # cr mask for ext int (cr0.54)
  48         ltr     %r2,%r2
  49         jz      .LsetctS1
  50         ahi     %r6,0x0800                      # cr mask for clock int (cr0.52)
  51         stck    .LtimeS1-.LbaseS1(%r13)         # initiate timeout
  52         al      %r2,.LtimeS1-.LbaseS1(%r13)
  53         st      %r2,.LtimeS1-.LbaseS1(%r13)
  54         sckc    .LtimeS1-.LbaseS1(%r13)
  55
  56 .LsetctS1:
  57         stctl   %c0,%c0,.LctlS1-.LbaseS1(%r13)  # enable required interrupts
  58         l       %r0,.LctlS1-.LbaseS1(%r13)
  59         lhi     %r1,~(0x200 | 0x800)            # clear old values
  60         nr      %r1,%r0
  61         or      %r1,%r6                         # set new value
  62         st      %r1,.LctlS1-.LbaseS1(%r13)
  63         lctl    %c0,%c0,.LctlS1-.LbaseS1(%r13)
  64         st      %r0,.LctlS1-.LbaseS1(%r13)
  65         lhi     %r2,2                           # return code for timeout
  66 .LloopS1:
  67         lpsw    .LwaitpswS1-.LbaseS1(%r13)      # wait until interrupt
  68 .LwaitS1:
  69         lh      %r7,LC_EXT_INT_CODE
  70         chi     %r7,0x1004                      # timeout?
  71         je      .LtimeoutS1
  72         chi     %r7,0x2401                      # service int?
  73         jne     .LloopS1
  74         sr      %r2,%r2
  75         l       %r3,LC_EXT_INT_PARAM
  76 .LtimeoutS1:
  77         lctl    %c0,%c0,.LctlS1-.LbaseS1(%r13)  # restore interrupt setting
  78         # restore old handler
  79         mvc     0(16,%r8),.LoldpswS1-.LbaseS1(%r13)
  80         lm      %r6,%r15,120(%r15)              # restore registers
  81         br      %r14                            # return to caller
  82
  83         .align  8
  84 .LoldpswS1:
  85         .long   0, 0, 0, 0                      # old ext int PSW
  86 .LextpswS1:
  87         .long   0x00080000, 0x80000000+.LwaitS1 # PSW to handle ext int
  88 #ifdef CONFIG_64BIT
  89 .LextpswS1_64:
  90         .quad   0x0000000180000000, .LwaitS1    # PSW to handle ext int, 64 bit
  91 #endif
  92 .LwaitpswS1:
  93         .long   0x010a0000, 0x00000000+.LloopS1 # PSW to wait for ext int
  94 .LtimeS1:
  95         .quad   0                               # current time
  96 .LctlS1:
  97         .long   0                               # CT0 contents
  98
  99 #
 100 # Subroutine to synchronously issue a service call.
 101 #
 102 # Parameters:
 103 #   R2  = command word
 104 #   R3  = sccb address
 105 #
 106 # Returns:
 107 #   R2  = 0 on success, 1 on failure
 108 #   R3  = sccb response code if R2 = 0
 109 #
 110
 111 _sclp_servc:
 112         stm     %r6,%r15,24(%r15)               # save registers
 113         ahi     %r15,-96                        # create stack frame
 114         lr      %r6,%r2                         # save command word
 115         lr      %r7,%r3                         # save sccb address
 116 .LretryS2:
 117         lhi     %r2,1                           # error return code
 118         .insn   rre,0xb2200000,%r6,%r7          # servc
 119         brc     1,.LendS2                       # exit if not operational
 120         brc     8,.LnotbusyS2                   # go on if not busy
 121         sr      %r2,%r2                         # wait until no longer busy
 122         bras    %r14,_sclp_wait_int
 123         j       .LretryS2                       # retry
 124 .LnotbusyS2:
 125         sr      %r2,%r2                         # wait until result
 126         bras    %r14,_sclp_wait_int
 127         sr      %r2,%r2
 128         lh      %r3,6(%r7)
 129 .LendS2:
 130         lm      %r6,%r15,120(%r15)              # restore registers
 131         br      %r14
 132
 133 #
 134 # Subroutine to set up the SCLP interface.
 135 #
 136 # Parameters:
 137 #   R2  = 0 to activate, non-zero to deactivate
 138 #
 139 # Returns:
 140 #   R2  = 0 on success, non-zero on failure
 141 #
 142
 143 _sclp_setup:
 144         stm     %r6,%r15,24(%r15)               # save registers
 145         ahi     %r15,-96                        # create stack frame
 146         basr    %r13,0                          # get base register
 147 .LbaseS3:
 148         l       %r6,.LsccbS0-.LbaseS3(%r13)     # prepare init mask sccb
 149         mvc     0(.LinitendS3-.LinitsccbS3,%r6),.LinitsccbS3-.LbaseS3(%r13)
 150         ltr     %r2,%r2                         # initialization?
 151         jz      .LdoinitS3                      # go ahead
 152         # clear masks
 153         xc      .LinitmaskS3-.LinitsccbS3(8,%r6),.LinitmaskS3-.LinitsccbS3(%r6)
 154 .LdoinitS3:
 155         l       %r2,.LwritemaskS3-.LbaseS3(%r13)# get command word
 156         lr      %r3,%r6                         # get sccb address
 157         bras    %r14,_sclp_servc                # issue service call
 158         ltr     %r2,%r2                         # servc successful?
 159         jnz     .LerrorS3
 160         chi     %r3,0x20                        # write mask successful?
 161         jne     .LerrorS3
 162         # check masks
 163         la      %r2,.LinitmaskS3-.LinitsccbS3(%r6)
 164         l       %r1,0(%r2)                      # receive mask ok?
 165         n       %r1,12(%r2)
 166         cl      %r1,0(%r2)
 167         jne     .LerrorS3
 168         l       %r1,4(%r2)                      # send mask ok?
 169         n       %r1,8(%r2)
 170         cl      %r1,4(%r2)
 171         sr      %r2,%r2
 172         je      .LendS3
 173 .LerrorS3:
 174         lhi     %r2,1                           # error return code
 175 .LendS3:
 176         lm      %r6,%r15,120(%r15)              # restore registers
 177         br      %r14
 178 .LwritemaskS3:
 179         .long   0x00780005                      # SCLP command for write mask
 180 .LinitsccbS3:
 181         .word   .LinitendS3-.LinitsccbS3
 182         .byte   0,0,0,0
 183         .word   0
 184         .word   0
 185         .word   4
 186 .LinitmaskS3:
 187         .long   0x80000000
 188         .long   0x40000000
 189         .long   0
 190         .long   0
 191 .LinitendS3:
 192
 193 #
 194 # Subroutine which prints a given text to the SCLP console.
 195 #
 196 # Parameters:
 197 #   R2  = address of nil-terminated ASCII text
 198 #
 199 # Returns:
 200 #   R2  = 0 on success, 1 on failure
 201 #
 202
 203 _sclp_print:
 204         stm     %r6,%r15,24(%r15)               # save registers
 205         ahi     %r15,-96                        # create stack frame
 206         basr    %r13,0                          # get base register
 207 .LbaseS4:
 208         l       %r8,.LsccbS0-.LbaseS4(%r13)     # prepare write data sccb
 209         mvc     0(.LmtoS4-.LwritesccbS4,%r8),.LwritesccbS4-.LbaseS4(%r13)
 210         la      %r7,.LmtoS4-.LwritesccbS4(%r8)  # current mto addr
 211         sr      %r0,%r0
 212         l       %r10,.Lascebc-.LbaseS4(%r13)    # address of translation table
 213 .LinitmtoS4:
 214         # initialize mto
 215         mvc     0(.LmtoendS4-.LmtoS4,%r7),.LmtoS4-.LbaseS4(%r13)
 216         lhi     %r6,.LmtoendS4-.LmtoS4          # current mto length
 217 .LloopS4:
 218         ic      %r0,0(%r2)                      # get character
 219         ahi     %r2,1
 220         ltr     %r0,%r0                         # end of string?
 221         jz      .LfinalizemtoS4
 222         chi     %r0,0x15                        # end of line (NL)?
 223         jz      .LfinalizemtoS4
 224         stc     %r0,0(%r6,%r7)                  # copy to mto
 225         la      %r11,0(%r6,%r7)
 226         tr      0(1,%r11),0(%r10)               # translate to EBCDIC
 227         ahi     %r6,1
 228         j       .LloopS4
 229 .LfinalizemtoS4:
 230         sth     %r6,0(%r7)                      # update mto length
 231         lh      %r9,.LmdbS4-.LwritesccbS4(%r8)  # update mdb length
 232         ar      %r9,%r6
 233         sth     %r9,.LmdbS4-.LwritesccbS4(%r8)
 234         lh      %r9,.LevbufS4-.LwritesccbS4(%r8)# update evbuf length
 235         ar      %r9,%r6
 236         sth     %r9,.LevbufS4-.LwritesccbS4(%r8)
 237         lh      %r9,0(%r8)                      # update sccb length
 238         ar      %r9,%r6
 239         sth     %r9,0(%r8)
 240         ar      %r7,%r6                         # update current mto address
 241         ltr     %r0,%r0                         # more characters?
 242         jnz     .LinitmtoS4
 243         l       %r2,.LwritedataS4-.LbaseS4(%r13)# write data
 244         lr      %r3,%r8
 245         bras    %r14,_sclp_servc
 246         ltr     %r2,%r2                         # servc successful?
 247         jnz     .LendS4
 248         chi     %r3,0x20                        # write data successful?
 249         je      .LendS4
 250         lhi     %r2,1                           # error return code
 251 .LendS4:
 252         lm      %r6,%r15,120(%r15)              # restore registers
 253         br      %r14
 254
 255 #
 256 # Function which prints a given text to the SCLP console.
 257 #
 258 # Parameters:
 259 #   R2  = address of nil-terminated ASCII text
 260 #
 261 # Returns:
 262 #   R2  = 0 on success, 1 on failure
 263 #
 264
 265 ENTRY(_sclp_print_early)
 266         stm     %r6,%r15,24(%r15)               # save registers
 267         ahi     %r15,-96                        # create stack frame
 268 #ifdef CONFIG_64BIT
 269         tm      LC_AR_MODE_ID,1
 270         jno     .Lesa2
 271         ahi     %r15,-80
 272         stmh    %r6,%r15,96(%r15)               # store upper register halves
 273 .Lesa2:
 274 #endif
 275         lr      %r10,%r2                        # save string pointer
 276         lhi     %r2,0
 277         bras    %r14,_sclp_setup                # enable console
 278         ltr     %r2,%r2
 279         jnz     .LendS5
 280         lr      %r2,%r10
 281         bras    %r14,_sclp_print                # print string
 282         ltr     %r2,%r2
 283         jnz     .LendS5
 284         lhi     %r2,1
 285         bras    %r14,_sclp_setup                # disable console
 286 .LendS5:
 287 #ifdef CONFIG_64BIT
 288         tm      LC_AR_MODE_ID,1
 289         jno     .Lesa3
 290         lmh     %r6,%r15,96(%r15)               # store upper register halves
 291         ahi     %r15,80
 292 .Lesa3:
 293 #endif
 294         lm      %r6,%r15,120(%r15)              # restore registers
 295         br      %r14
 296
 297 .LwritedataS4:
 298         .long   0x00760005                      # SCLP command for write data
 299 .LwritesccbS4:
 300         # sccb
 301         .word   .LmtoS4-.LwritesccbS4
 302         .byte   0
 303         .byte   0,0,0
 304         .word   0
 305
 306         # evbuf
 307 .LevbufS4:
 308         .word   .LmtoS4-.LevbufS4
 309         .byte   0x02
 310         .byte   0
 311         .word   0
 312
 313 .LmdbS4:
 314         # mdb
 315         .word   .LmtoS4-.LmdbS4
 316         .word   1
 317         .long   0xd4c4c240
 318         .long   1
 319
 320         # go
 321 .LgoS4:
 322         .word   .LmtoS4-.LgoS4
 323         .word   1
 324         .long   0
 325         .byte   0,0,0,0,0,0,0,0
 326         .byte   0,0,0
 327         .byte   0
 328         .byte   0,0,0,0,0,0,0
 329         .byte   0
 330         .word   0
 331         .byte   0,0,0,0,0,0,0,0,0,0
 332         .byte   0,0,0,0,0,0,0,0
 333         .byte   0,0,0,0,0,0,0,0
 334
 335 .LmtoS4:
 336         .word   .LmtoendS4-.LmtoS4
 337         .word   4
 338         .word   0x1000
 339         .byte   0
 340         .byte   0,0,0
 341 .LmtoendS4:
 342
 343         # Global constants
 344 .LsccbS0:
 345         .long   _sclp_work_area
 346 .Lascebc:
 347         .long   _ascebc
 348
 349 .section .data,"aw",@progbits
 350         .balign 4096
 351 _sclp_work_area:
 352         .fill   4096
 353 .previous