tools/kvm/hw/rtc.c

   1 #include "kvm/rtc.h"
   2
   3 #include "kvm/ioport.h"
   4 #include "kvm/kvm.h"
   5
   6 #include <time.h>
   7
   8 static u8 cmos_index;
   9
  10 #define CMOS_RTC_SECONDS                0x00
  11 #define CMOS_RTC_MINUTES                0x02
  12 #define CMOS_RTC_HOURS                  0x04
  13 #define CMOS_RTC_DATE_OF_MONTH          0x07
  14 #define CMOS_RTC_MONTH                  0x08
  15 #define CMOS_RTC_YEAR                   0x09
  16
  17 static inline unsigned char bin2bcd(unsigned val)
  18 {
  19         return ((val / 10) << 4) + val % 10;
  20 }
  21
  22 static bool cmos_ram_data_in(struct ioport *ioport, struct kvm *kvm, u16 port, void *data, int size)
  23 {
  24         struct tm *tm;
  25         time_t ti;
  26
  27         time(&ti);
  28
  29         tm = gmtime(&ti);
  30
  31         switch (cmos_index) {
  32         case CMOS_RTC_SECONDS:
  33                 ioport__write8(data, bin2bcd(tm->tm_sec));
  34                 break;
  35         case CMOS_RTC_MINUTES:
  36                 ioport__write8(data, bin2bcd(tm->tm_min));
  37                 break;
  38         case CMOS_RTC_HOURS:
  39                 ioport__write8(data, bin2bcd(tm->tm_hour));
  40                 break;
  41         case CMOS_RTC_DATE_OF_MONTH:
  42                 ioport__write8(data, bin2bcd(tm->tm_mday));
  43                 break;
  44         case CMOS_RTC_MONTH:
  45                 ioport__write8(data, bin2bcd(tm->tm_mon + 1));
  46                 break;
  47         case CMOS_RTC_YEAR:
  48                 ioport__write8(data, bin2bcd(tm->tm_year));
  49                 break;
  50         }
  51
  52         return true;
  53 }
  54
  55 static bool cmos_ram_data_out(struct ioport *ioport, struct kvm *kvm, u16 port, void *data, int size)
  56 {
  57         return true;
  58 }
  59
  60 static struct ioport_operations cmos_ram_data_ioport_ops = {
  61         .io_out         = cmos_ram_data_out,
  62         .io_in          = cmos_ram_data_in,
  63 };
  64
  65 static bool cmos_ram_index_out(struct ioport *ioport, struct kvm *kvm, u16 port, void *data, int size)
  66 {
  67         u8 value;
  68
  69         value   = ioport__read8(data);
  70
  71         kvm->nmi_disabled       = value & (1UL << 7);
  72
  73         cmos_index              = value & ~(1UL << 7);
  74
  75         return true;
  76 }
  77
  78 static struct ioport_operations cmos_ram_index_ioport_ops = {
  79         .io_out         = cmos_ram_index_out,
  80 };
  81
  82 void rtc__init(void)
  83 {
  84         /* PORT 0070-007F - CMOS RAM/RTC (REAL TIME CLOCK) */
  85         ioport__register(0x0070, &cmos_ram_index_ioport_ops, 1, NULL);
  86         ioport__register(0x0071, &cmos_ram_data_ioport_ops, 1, NULL);
  87 }