i386/standford/2004/src/lab4/kern/kclock.h

   1 /* See COPYRIGHT for copyright information. */
   2
   3 #ifndef _KERN_KCLOCK_H_
   4 #define _KERN_KCLOCK_H_
   5
   6 #define IO_RTC          0x070           /* RTC port */
   7
   8 #define MC_NVRAM_START  0xe     /* start of NVRAM: offset 14 */
   9 #define MC_NVRAM_SIZE   50      /* 50 bytes of NVRAM */
  10
  11 /* NVRAM bytes 7 & 8: base memory size */
  12 #define NVRAM_BASELO    (MC_NVRAM_START + 7)    /* low byte; RTC off. 0x15 */
  13 #define NVRAM_BASEHI    (MC_NVRAM_START + 8)    /* high byte; RTC off. 0x16 */
  14
  15 /* NVRAM bytes 9 & 10: extended memory size */
  16 #define NVRAM_EXTLO     (MC_NVRAM_START + 9)    /* low byte; RTC off. 0x17 */
  17 #define NVRAM_EXTHI     (MC_NVRAM_START + 10)   /* high byte; RTC off. 0x18 */
  18
  19 /* NVRAM bytes 34 and 35: extended memory POSTed size */
  20 #define NVRAM_PEXTLO    (MC_NVRAM_START + 34)   /* low byte; RTC off. 0x30 */
  21 #define NVRAM_PEXTHI    (MC_NVRAM_START + 35)   /* high byte; RTC off. 0x31 */
  22
  23 /* NVRAM byte 36: current century.  (please increment in Dec99!) */
  24 #define NVRAM_CENTURY   (MC_NVRAM_START + 36)   /* RTC offset 0x32 */
  25
  26 u_int mc146818_read(void *sc, u_int reg);
  27 void mc146818_write(void *sc, u_int reg, u_int datum);
  28 void kclock_init(void);
  29
  30 #endif  // not _KERN_KCLOCK_H_