+++ /dev/null
-/****************************************************************************/
-/*
- * linux/arch/sh/boards/snapgear/rtc.c -- Secureedge5410 RTC code
- *
- * Copyright (C) 2002 David McCullough <davidm@snapgear.com>
- * Copyright (C) 2003 Paul Mundt <lethal@linux-sh.org>
- *
- * The SecureEdge5410 can have one of 2 real time clocks, the SH
- * built in version or the preferred external DS1302. Here we work out
- * each to see what we have and then run with it.
- */
-/****************************************************************************/
-
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/sched.h>
-#include <linux/time.h>
-#include <linux/rtc.h>
-#include <linux/mc146818rtc.h>
-#include <asm/io.h>
-
-static int use_ds1302;
-
-/****************************************************************************/
-/*
- * we need to implement a DS1302 driver here that can operate in
- * conjunction with the builtin rtc driver which is already quite friendly
- */
-/*****************************************************************************/
-
-#define RTC_CMD_READ 0x81 /* Read command */
-#define RTC_CMD_WRITE 0x80 /* Write command */
-
-#define RTC_ADDR_YEAR 0x06 /* Address of year register */
-#define RTC_ADDR_DAY 0x05 /* Address of day of week register */
-#define RTC_ADDR_MON 0x04 /* Address of month register */
-#define RTC_ADDR_DATE 0x03 /* Address of day of month register */
-#define RTC_ADDR_HOUR 0x02 /* Address of hour register */
-#define RTC_ADDR_MIN 0x01 /* Address of minute register */
-#define RTC_ADDR_SEC 0x00 /* Address of second register */
-
-#define RTC_RESET 0x1000
-#define RTC_IODATA 0x0800
-#define RTC_SCLK 0x0400
-
-#define set_dirp(x)
-#define get_dirp(x) 0
-#define set_dp(x) SECUREEDGE_WRITE_IOPORT(x, 0x1c00)
-#define get_dp(x) SECUREEDGE_READ_IOPORT()
-
-static void ds1302_sendbits(unsigned int val)
-{
- int i;
-
- for (i = 8; (i); i--, val >>= 1) {
- set_dp((get_dp() & ~RTC_IODATA) | ((val & 0x1) ? RTC_IODATA : 0));
- set_dp(get_dp() | RTC_SCLK); // clock high
- set_dp(get_dp() & ~RTC_SCLK); // clock low
- }
-}
-
-static unsigned int ds1302_recvbits(void)
-{
- unsigned int val;
- int i;
-
- for (i = 0, val = 0; (i < 8); i++) {
- val |= (((get_dp() & RTC_IODATA) ? 1 : 0) << i);
- set_dp(get_dp() | RTC_SCLK); // clock high
- set_dp(get_dp() & ~RTC_SCLK); // clock low
- }
- return(val);
-}
-
-static unsigned int ds1302_readbyte(unsigned int addr)
-{
- unsigned int val;
- unsigned long flags;
-
- local_irq_save(flags);
- set_dirp(get_dirp() | RTC_RESET | RTC_IODATA | RTC_SCLK);
- set_dp(get_dp() & ~(RTC_RESET | RTC_IODATA | RTC_SCLK));
-
- set_dp(get_dp() | RTC_RESET);
- ds1302_sendbits(((addr & 0x3f) << 1) | RTC_CMD_READ);
- set_dirp(get_dirp() & ~RTC_IODATA);
- val = ds1302_recvbits();
- set_dp(get_dp() & ~RTC_RESET);
- local_irq_restore(flags);
-
- return(val);
-}
-
-static void ds1302_writebyte(unsigned int addr, unsigned int val)
-{
- unsigned long flags;
-
- local_irq_save(flags);
- set_dirp(get_dirp() | RTC_RESET | RTC_IODATA | RTC_SCLK);
- set_dp(get_dp() & ~(RTC_RESET | RTC_IODATA | RTC_SCLK));
- set_dp(get_dp() | RTC_RESET);
- ds1302_sendbits(((addr & 0x3f) << 1) | RTC_CMD_WRITE);
- ds1302_sendbits(val);
- set_dp(get_dp() & ~RTC_RESET);
- local_irq_restore(flags);
-}
-
-static void ds1302_reset(void)
-{
- unsigned long flags;
- /* Hardware dependent reset/init */
- local_irq_save(flags);
- set_dirp(get_dirp() | RTC_RESET | RTC_IODATA | RTC_SCLK);
- set_dp(get_dp() & ~(RTC_RESET | RTC_IODATA | RTC_SCLK));
- local_irq_restore(flags);
-}
-
-/*****************************************************************************/
-
-static inline int bcd2int(int val)
-{
- return((((val & 0xf0) >> 4) * 10) + (val & 0xf));
-}
-
-static inline int int2bcd(int val)
-{
- return(((val / 10) << 4) + (val % 10));
-}
-
-/*****************************************************************************/
-/*
- * Write and Read some RAM in the DS1302, if it works assume it's there
- * Otherwise use the SH4 internal RTC
- */
-
-void snapgear_rtc_gettimeofday(struct timespec *);
-int snapgear_rtc_settimeofday(const time_t);
-
-void __init secureedge5410_rtc_init(void)
-{
- unsigned char *test = "snapgear";
- int i;
-
- ds1302_reset();
-
- use_ds1302 = 1;
-
- for (i = 0; test[i]; i++)
- ds1302_writebyte(32 + i, test[i]);
-
- for (i = 0; test[i]; i++)
- if (ds1302_readbyte(32 + i) != test[i]) {
- use_ds1302 = 0;
- break;
- }
-
- if (use_ds1302) {
- rtc_sh_get_time = snapgear_rtc_gettimeofday;
- rtc_sh_set_time = snapgear_rtc_settimeofday;
- }
-
- printk("SnapGear RTC: using %s rtc.\n", use_ds1302 ? "ds1302" : "internal");
-}
-
-/****************************************************************************/
-/*
- * our generic interface that chooses the correct code to use
- */
-
-void snapgear_rtc_gettimeofday(struct timespec *ts)
-{
- unsigned int sec, min, hr, day, mon, yr;
-
- if (!use_ds1302)
- return;
-
- sec = bcd2int(ds1302_readbyte(RTC_ADDR_SEC));
- min = bcd2int(ds1302_readbyte(RTC_ADDR_MIN));
- hr = bcd2int(ds1302_readbyte(RTC_ADDR_HOUR));
- day = bcd2int(ds1302_readbyte(RTC_ADDR_DATE));
- mon = bcd2int(ds1302_readbyte(RTC_ADDR_MON));
- yr = bcd2int(ds1302_readbyte(RTC_ADDR_YEAR));
-
-bad_time:
- if (yr > 99 || mon < 1 || mon > 12 || day > 31 || day < 1 ||
- hr > 23 || min > 59 || sec > 59) {
- printk(KERN_ERR
- "SnapGear RTC: invalid value, resetting to 1 Jan 2000\n");
- ds1302_writebyte(RTC_ADDR_MIN, min = 0);
- ds1302_writebyte(RTC_ADDR_HOUR, hr = 0);
- ds1302_writebyte(RTC_ADDR_DAY, 7);
- ds1302_writebyte(RTC_ADDR_DATE, day = 1);
- ds1302_writebyte(RTC_ADDR_MON, mon = 1);
- ds1302_writebyte(RTC_ADDR_YEAR, yr = 0);
- ds1302_writebyte(RTC_ADDR_SEC, sec = 0);
- }
-
- ts->tv_sec = mktime(2000 + yr, mon, day, hr, min, sec);
- if (ts->tv_sec < 0) {
-#if 0
- printk("BAD TIME %d %d %d %d %d %d\n", yr, mon, day, hr, min, sec);
-#endif
- yr = 100;
- goto bad_time;
- }
- ts->tv_nsec = 0;
-}
-
-int snapgear_rtc_settimeofday(const time_t secs)
-{
- int retval = 0;
- int real_seconds, real_minutes, cmos_minutes;
- unsigned long nowtime;
-
- if (!use_ds1302)
- return 0;
-
-/*
- * This is called direct from the kernel timer handling code.
- * It is supposed to synchronize the kernel clock to the RTC.
- */
-
- nowtime = secs;
-
- /* STOP RTC */
- ds1302_writebyte(RTC_ADDR_SEC, ds1302_readbyte(RTC_ADDR_SEC) | 0x80);
-
- cmos_minutes = bcd2int(ds1302_readbyte(RTC_ADDR_MIN));
-
- /*
- * since we're only adjusting minutes and seconds,
- * don't interfere with hour overflow. This avoids
- * messing with unknown time zones but requires your
- * RTC not to be off by more than 15 minutes
- */
- real_seconds = nowtime % 60;
- real_minutes = nowtime / 60;
- if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1)
- real_minutes += 30; /* correct for half hour time zone */
- real_minutes %= 60;
-
- if (abs(real_minutes - cmos_minutes) < 30) {
- ds1302_writebyte(RTC_ADDR_MIN, int2bcd(real_minutes));
- ds1302_writebyte(RTC_ADDR_SEC, int2bcd(real_seconds));
- } else {
- printk(KERN_WARNING
- "SnapGear RTC: can't update from %d to %d\n",
- cmos_minutes, real_minutes);
- retval = -1;
- }
-
- /* START RTC */
- ds1302_writebyte(RTC_ADDR_SEC, ds1302_readbyte(RTC_ADDR_SEC) & ~0x80);
- return(0);
-}
-
-unsigned char secureedge5410_cmos_read(int addr)
-{
- unsigned char val = 0;
-
- if (!use_ds1302)
- return(__CMOS_READ(addr, w));
-
- switch(addr) {
- case RTC_SECONDS: val = ds1302_readbyte(RTC_ADDR_SEC); break;
- case RTC_SECONDS_ALARM: break;
- case RTC_MINUTES: val = ds1302_readbyte(RTC_ADDR_MIN); break;
- case RTC_MINUTES_ALARM: break;
- case RTC_HOURS: val = ds1302_readbyte(RTC_ADDR_HOUR); break;
- case RTC_HOURS_ALARM: break;
- case RTC_DAY_OF_WEEK: val = ds1302_readbyte(RTC_ADDR_DAY); break;
- case RTC_DAY_OF_MONTH: val = ds1302_readbyte(RTC_ADDR_DATE); break;
- case RTC_MONTH: val = ds1302_readbyte(RTC_ADDR_MON); break;
- case RTC_YEAR: val = ds1302_readbyte(RTC_ADDR_YEAR); break;
- case RTC_REG_A: /* RTC_FREQ_SELECT */ break;
- case RTC_REG_B: /* RTC_CONTROL */ break;
- case RTC_REG_C: /* RTC_INTR_FLAGS */ break;
- case RTC_REG_D: val = RTC_VRT /* RTC_VALID */; break;
- default: break;
- }
-
- return(val);
-}
-
-void secureedge5410_cmos_write(unsigned char val, int addr)
-{
- if (!use_ds1302) {
- __CMOS_WRITE(val, addr, w);
- return;
- }
-
- switch(addr) {
- case RTC_SECONDS: ds1302_writebyte(RTC_ADDR_SEC, val); break;
- case RTC_SECONDS_ALARM: break;
- case RTC_MINUTES: ds1302_writebyte(RTC_ADDR_MIN, val); break;
- case RTC_MINUTES_ALARM: break;
- case RTC_HOURS: ds1302_writebyte(RTC_ADDR_HOUR, val); break;
- case RTC_HOURS_ALARM: break;
- case RTC_DAY_OF_WEEK: ds1302_writebyte(RTC_ADDR_DAY, val); break;
- case RTC_DAY_OF_MONTH: ds1302_writebyte(RTC_ADDR_DATE, val); break;
- case RTC_MONTH: ds1302_writebyte(RTC_ADDR_MON, val); break;
- case RTC_YEAR: ds1302_writebyte(RTC_ADDR_YEAR, val); break;
- case RTC_REG_A: /* RTC_FREQ_SELECT */ break;
- case RTC_REG_B: /* RTC_CONTROL */ break;
- case RTC_REG_C: /* RTC_INTR_FLAGS */ break;
- case RTC_REG_D: /* RTC_VALID */ break;
- default: break;
- }
-}
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