kern/kclock.h

   1 /* See COPYRIGHT for copyright information. */
   2
   3 #ifndef JOS_KERN_KCLOCK_H
   4 #define JOS_KERN_KCLOCK_H
   5 #ifndef JOS_KERNEL
   6 # error "This is a JOS kernel header; user programs should not #include it"
   7 #endif
   8
   9 #define IO_RTC          0x070           /* RTC port */
  10
  11 #define MC_NVRAM_START  0xe     /* start of NVRAM: offset 14 */
  12 #define MC_NVRAM_SIZE   50      /* 50 bytes of NVRAM */
  13
  14 /* NVRAM bytes 7 & 8: base memory size */
  15 #define NVRAM_BASELO    (MC_NVRAM_START + 7)    /* low byte; RTC off. 0x15 */
  16 #define NVRAM_BASEHI    (MC_NVRAM_START + 8)    /* high byte; RTC off. 0x16 */
  17
  18 /* NVRAM bytes 9 & 10: extended memory size */
  19 #define NVRAM_EXTLO     (MC_NVRAM_START + 9)    /* low byte; RTC off. 0x17 */
  20 #define NVRAM_EXTHI     (MC_NVRAM_START + 10)   /* high byte; RTC off. 0x18 */
  21
  22 /* NVRAM bytes 34 and 35: extended memory POSTed size */
  23 #define NVRAM_PEXTLO    (MC_NVRAM_START + 34)   /* low byte; RTC off. 0x30 */
  24 #define NVRAM_PEXTHI    (MC_NVRAM_START + 35)   /* high byte; RTC off. 0x31 */
  25
  26 /* NVRAM byte 36: current century.  (please increment in Dec99!) */
  27 #define NVRAM_CENTURY   (MC_NVRAM_START + 36)   /* RTC offset 0x32 */
  28
  29 unsigned mc146818_read(unsigned reg);
  30 void mc146818_write(unsigned reg, unsigned datum);
  31 void kclock_init(void);
  32
  33 #endif  // !JOS_KERN_KCLOCK_H