linux/arch/powerpc/platforms/powernv/opal-rtc.c

98 lines
2.3 KiB
C

/*
* PowerNV Real Time Clock.
*
* Copyright 2011 IBM Corp.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/time.h>
#include <linux/bcd.h>
#include <linux/rtc.h>
#include <linux/delay.h>
#include <asm/opal.h>
#include <asm/firmware.h>
static void opal_to_tm(u32 y_m_d, u64 h_m_s_ms, struct rtc_time *tm)
{
tm->tm_year = ((bcd2bin(y_m_d >> 24) * 100) +
bcd2bin((y_m_d >> 16) & 0xff)) - 1900;
tm->tm_mon = bcd2bin((y_m_d >> 8) & 0xff) - 1;
tm->tm_mday = bcd2bin(y_m_d & 0xff);
tm->tm_hour = bcd2bin((h_m_s_ms >> 56) & 0xff);
tm->tm_min = bcd2bin((h_m_s_ms >> 48) & 0xff);
tm->tm_sec = bcd2bin((h_m_s_ms >> 40) & 0xff);
GregorianDay(tm);
}
unsigned long __init opal_get_boot_time(void)
{
struct rtc_time tm;
u32 y_m_d;
u64 h_m_s_ms;
long rc = OPAL_BUSY;
while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
rc = opal_rtc_read(&y_m_d, &h_m_s_ms);
if (rc == OPAL_BUSY_EVENT)
opal_poll_events(NULL);
else
mdelay(10);
}
if (rc != OPAL_SUCCESS)
return 0;
opal_to_tm(y_m_d, h_m_s_ms, &tm);
return mktime(tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday,
tm.tm_hour, tm.tm_min, tm.tm_sec);
}
void opal_get_rtc_time(struct rtc_time *tm)
{
long rc = OPAL_BUSY;
u32 y_m_d;
u64 h_m_s_ms;
while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
rc = opal_rtc_read(&y_m_d, &h_m_s_ms);
if (rc == OPAL_BUSY_EVENT)
opal_poll_events(NULL);
else
mdelay(10);
}
if (rc != OPAL_SUCCESS)
return;
opal_to_tm(y_m_d, h_m_s_ms, tm);
}
int opal_set_rtc_time(struct rtc_time *tm)
{
long rc = OPAL_BUSY;
u32 y_m_d = 0;
u64 h_m_s_ms = 0;
y_m_d |= ((u32)bin2bcd((tm->tm_year + 1900) / 100)) << 24;
y_m_d |= ((u32)bin2bcd((tm->tm_year + 1900) % 100)) << 16;
y_m_d |= ((u32)bin2bcd((tm->tm_mon + 1))) << 8;
y_m_d |= ((u32)bin2bcd(tm->tm_mday));
h_m_s_ms |= ((u64)bin2bcd(tm->tm_hour)) << 56;
h_m_s_ms |= ((u64)bin2bcd(tm->tm_min)) << 48;
h_m_s_ms |= ((u64)bin2bcd(tm->tm_sec)) << 40;
while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
rc = opal_rtc_write(y_m_d, h_m_s_ms);
if (rc == OPAL_BUSY_EVENT)
opal_poll_events(NULL);
else
mdelay(10);
}
return rc == OPAL_SUCCESS ? 0 : -EIO;
}