arch/m68k/sun3x/time.c

   1 /*
   2  *  linux/arch/m68k/sun3x/time.c
   3  *
   4  *  Sun3x-specific time handling
   5  */
   6
   7 #include <linux/types.h>
   8 #include <linux/init.h>
   9 #include <linux/sched.h>
  10 #include <linux/kernel_stat.h>
  11 #include <linux/interrupt.h>
  12
  13 #include <asm/irq.h>
  14 #include <asm/io.h>
  15 #include <asm/system.h>
  16 #include <asm/traps.h>
  17 #include <asm/sun3x.h>
  18
  19 #include "time.h"
  20
  21 #define M_CONTROL 0xf8
  22 #define M_SEC     0xf9
  23 #define M_MIN     0xfa
  24 #define M_HOUR    0xfb
  25 #define M_DAY     0xfc
  26 #define M_DATE    0xfd
  27 #define M_MONTH   0xfe
  28 #define M_YEAR    0xff
  29
  30 #define C_WRITE   0x80
  31 #define C_READ    0x40
  32 #define C_SIGN    0x20
  33 #define C_CALIB   0x1f
  34
  35 #define BCD_TO_BIN(val) (((val)&15) + ((val)>>4)*10)
  36
  37 /* Read the Mostek */
  38 void sun3x_gettod (int *yearp, int *monp, int *dayp,
  39                    int *hourp, int *minp, int *secp)
  40 {
  41     volatile unsigned char *eeprom = (unsigned char *)SUN3X_EEPROM;
  42
  43     /* Stop updates */
  44     *(eeprom + M_CONTROL) |= C_READ;
  45
  46     /* Read values */
  47     *yearp = BCD_TO_BIN(*(eeprom + M_YEAR));
  48     *monp  = BCD_TO_BIN(*(eeprom + M_MONTH));
  49     *dayp  = BCD_TO_BIN(*(eeprom + M_DATE));
  50     *hourp = BCD_TO_BIN(*(eeprom + M_HOUR));
  51     *minp  = BCD_TO_BIN(*(eeprom + M_MIN));
  52     *secp  = BCD_TO_BIN(*(eeprom + M_SEC));
  53
  54     /* Restart updates */
  55     *(eeprom + M_CONTROL) &= ~C_READ;
  56 }
  57
  58 /* Not much we can do here */
  59 unsigned long sun3x_gettimeoffset (void)
  60 {
  61     return 0L;
  62 }
  63
  64 static void sun3x_timer_tick(int irq, void *dev_id, struct pt_regs *regs)
  65 {
  66     void (*vector)(int, void *, struct pt_regs *) = dev_id;
  67
  68     /* Clear the pending interrupt - pulse the enable line low */
  69     disable_irq(5);
  70     enable_irq(5);
  71
  72     vector(irq, NULL, regs);
  73 }
  74
  75 __initfunc(void sun3x_sched_init(void (*vector)(int, void *, struct pt_regs *)))
  76 {
  77     sys_request_irq(5, sun3x_timer_tick, IRQ_FLG_STD, "timer tick", vector);
  78
  79     /* Pulse enable low to get the clock started */
  80     disable_irq(5);
  81     enable_irq(5);
  82 }