include/asm-i386/mach-default/mach_reboot.h

   1 /*
   2  *  arch/i386/mach-generic/mach_reboot.h
   3  *
   4  *  Machine specific reboot functions for generic.
   5  *  Split out from reboot.c by Osamu Tomita <tomita@cinet.co.jp>
   6  */
   7 #ifndef _MACH_REBOOT_H
   8 #define _MACH_REBOOT_H
   9
  10 static inline void kb_wait(void)
  11 {
  12         int i;
  13
  14         for (i = 0; i < 0x10000; i++)
  15                 if ((inb_p(0x64) & 0x02) == 0)
  16                         break;
  17 }
  18
  19 static inline void mach_reboot(void)
  20 {
  21         int i;
  22
  23         /* old method, works on most machines */
  24         for (i = 0; i < 10; i++) {
  25                 kb_wait();
  26                 udelay(50);
  27                 outb(0xfe, 0x64);       /* pulse reset low */
  28                 udelay(50);
  29         }
  30
  31         /* New method: sets the "System flag" which, when set, indicates
  32          * successful completion of the keyboard controller self-test (Basic
  33          * Assurance Test, BAT).  This is needed for some machines with no
  34          * keyboard plugged in.  This read-modify-write sequence sets only the
  35          * system flag
  36          */
  37         for (i = 0; i < 10; i++) {
  38                 int cmd;
  39
  40                 outb(0x20, 0x64);       /* read Controller Command Byte */
  41                 udelay(50);
  42                 kb_wait();
  43                 udelay(50);
  44                 cmd = inb(0x60);
  45                 udelay(50);
  46                 kb_wait();
  47                 udelay(50);
  48                 outb(0x60, 0x64);       /* write Controller Command Byte */
  49                 udelay(50);
  50                 kb_wait();
  51                 udelay(50);
  52                 outb(cmd | 0x04, 0x60); /* set "System flag" */
  53                 udelay(50);
  54                 kb_wait();
  55                 udelay(50);
  56                 outb(0xfe, 0x64);       /* pulse reset low */
  57                 udelay(50);
  58         }
  59 }
  60
  61 #endif /* !_MACH_REBOOT_H */