sortix-mirror/kernel/x86-family/cmos.cpp
Jonas 'Sortie' Termansen 2b72262b4f Relicense Sortix to the ISC license.
I hereby relicense all my work on Sortix under the ISC license as below.

All Sortix contributions by other people are already under this license,
are not substantial enough to be copyrightable, or have been removed.

All imported code from other projects is compatible with this license.

All GPL licensed code from other projects had previously been removed.

Copyright 2011-2016 Jonas 'Sortie' Termansen and contributors.

Permission to use, copy, modify, and distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
2016-03-05 22:21:50 +01:00

150 lines
3.6 KiB
C++

/*
* Copyright (c) 2013, 2014 Jonas 'Sortie' Termansen.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* x86-family/cmos.cpp
* Provides access to CMOS and the real-time clock.
*/
#include <sys/types.h>
#include <stdint.h>
#include <time.h>
#include <timespec.h>
#include <sortix/clock.h>
#include <sortix/kernel/clock.h>
#include <sortix/kernel/cpu.h>
#include <sortix/kernel/ioport.h>
#include <sortix/kernel/kernel.h>
#include <sortix/kernel/time.h>
namespace Sortix {
namespace CMOS {
const uint16_t CMOS_ADDRESS_REG = 0x70;
const uint16_t CMOS_DATA_REG = 0x71;
uint8_t ReadRTC(uint8_t reg)
{
outport8(CMOS_ADDRESS_REG, reg);
return inport8(CMOS_DATA_REG);
}
bool IsRTCUpdateInProgress()
{
return ReadRTC(0x0A) & 0x80;
}
uint8_t DecodeBCD(uint8_t bcd)
{
return bcd / 16 * 10 + bcd % 16;
}
struct rtc_values
{
uint8_t second;
uint8_t minute;
uint8_t hour;
uint8_t day;
uint8_t month;
uint8_t year;
uint8_t century;
uint8_t reg_b;
};
bool are_rtc_values_equal(struct rtc_values a, struct rtc_values b)
{
return a.second == b.second &&
a.minute == b.minute &&
a.hour == b.hour &&
a.day == b.day &&
a.month == b.month &&
a.year == b.year &&
a.century == b.century &&
a.reg_b == b.reg_b;
}
struct rtc_values ReadRTCValues()
{
while ( IsRTCUpdateInProgress() );
struct rtc_values result;
result.second = ReadRTC(0x00);
result.minute = ReadRTC(0x02);
result.hour = ReadRTC(0x04);
result.day = ReadRTC(0x07);
result.month = ReadRTC(0x08);
result.year = ReadRTC(0x09);
result.century = ReadRTC(0x32);
result.reg_b = ReadRTC(0x0B);
return result;
}
void Init()
{
struct rtc_values values_first = ReadRTCValues();
struct rtc_values values_second = ReadRTCValues();
while ( !are_rtc_values_equal(values_first, values_second) )
{
values_first = values_second;
values_second = ReadRTCValues();
}
uint8_t second = values_first.second;
uint8_t minute = values_first.minute;
uint8_t hour = values_first.hour;
uint8_t day = values_first.day;
uint8_t month = values_first.month;
uint8_t year = values_first.year;
uint8_t century = values_first.century;
uint8_t reg_b = values_first.reg_b;
bool hour12 = !(reg_b & 0x02);
bool is_pm = hour12 && hour & 0x80;
if ( hour12 )
hour &= 0x7F;
if ( !(reg_b & 0x04) )
{
second = DecodeBCD(second);
minute = DecodeBCD(minute);
hour = DecodeBCD(hour);
day = DecodeBCD(day);
month = DecodeBCD(month);
year = DecodeBCD(year);
century = DecodeBCD(century);
}
if ( hour12 && is_pm )
hour = (hour + 12) % 24;
time_t full_year = century * 100 + year;
struct tm tm;
memset(&tm, 0, sizeof(tm));
tm.tm_sec = second;
tm.tm_min = minute;
tm.tm_hour = hour;
tm.tm_mday = day ;
tm.tm_mon = month - 1;
tm.tm_year = full_year - 1900;
time_t now = timegm(&tm);
struct timespec current_time = timespec_make(now, 0);
Time::GetClock(CLOCK_REALTIME)->Set(&current_time, NULL);
}
} // namespace CMOS
} // namespace Sortix