arch/s390x/kernel/cpcmd.c

   1 /*
   2  *  arch/s390/kernel/cpcmd.c
   3  *
   4  *  S390 version
   5  *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
   6  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
   7  */
   8
   9 #include <linux/string.h>
  10 #include <linux/spinlock.h>
  11 #include <asm/cpcmd.h>
  12 #include <asm/ebcdic.h>
  13 #include <asm/system.h>
  14
  15 static spinlock_t cpcmd_lock = SPIN_LOCK_UNLOCKED;
  16 static char cpcmd_buf[128];
  17
  18 void cpcmd(char *cmd, char *response, int rlen)
  19 {
  20         const int mask = 0x40000000L;
  21         unsigned long flags;
  22         int cmdlen;
  23
  24         spin_lock_irqsave(&cpcmd_lock, flags);
  25         cmdlen = strlen(cmd);
  26         strcpy(cpcmd_buf, cmd);
  27         ASCEBC(cpcmd_buf, cmdlen);
  28
  29         if (response != NULL && rlen > 0) {
  30                 asm volatile ("   lrag  2,0(%0)\n"
  31                               "   lgr   4,%1\n"
  32                               "   o     4,%4\n"
  33                               "   lrag  3,0(%2)\n"
  34                               "   lgr   5,%3\n"
  35                               "   sam31\n"
  36                               "   .long 0x83240008 # Diagnose 83\n"
  37                               "   sam64"
  38                               : /* no output */
  39                               : "a" (cpcmd_buf), "d" (cmdlen),
  40                                 "a" (response), "d" (rlen), "m" (mask)
  41                               : "2", "3", "4", "5" );
  42                 EBCASC(response, rlen);
  43         } else {
  44                 asm volatile ("   lrag  2,0(%0)\n"
  45                               "   lgr   3,%1\n"
  46                               "   sam31\n"
  47                               "   .long 0x83230008 # Diagnose 83\n"
  48                               "   sam64"
  49                               : /* no output */
  50                               : "a" (cpcmd_buf), "d" (cmdlen)
  51                               : "2", "3"  );
  52         }
  53         spin_unlock_irqrestore(&cpcmd_lock, flags);
  54 }
  55