1 files changed, 348 insertions, 0 deletions

diff --git a/arch/m68k/atari/time.c b/arch/m68k/atari/time.c
new file mode 100644
index 000000000000..6df7fb60dfea
--- /dev/null
+++ b/arch/m68k/atari/time.c
@@ -0,0 +1,348 @@
+/*
+ * linux/arch/m68k/atari/time.c
+ *
+ * Atari time and real time clock stuff
+ *
+ * Assembled of parts of former atari/config.c 97-12-18 by Roman Hodek
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/types.h>
+#include <linux/mc146818rtc.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/rtc.h>
+#include <linux/bcd.h>
+
+#include <asm/atariints.h>
+
+void __init
+atari_sched_init(irqreturn_t (*timer_routine)(int, void *, struct pt_regs *))
+{
+    /* set Timer C data Register */
+    mfp.tim_dt_c = INT_TICKS;
+    /* start timer C, div = 1:100 */
+    mfp.tim_ct_cd = (mfp.tim_ct_cd & 15) | 0x60;
+    /* install interrupt service routine for MFP Timer C */
+    request_irq(IRQ_MFP_TIMC, timer_routine, IRQ_TYPE_SLOW,
+                "timer", timer_routine);
+}
+
+/* ++andreas: gettimeoffset fixed to check for pending interrupt */
+
+#define TICK_SIZE 10000
+
+/* This is always executed with interrupts disabled.  */
+unsigned long atari_gettimeoffset (void)
+{
+  unsigned long ticks, offset = 0;
+
+  /* read MFP timer C current value */
+  ticks = mfp.tim_dt_c;
+  /* The probability of underflow is less than 2% */
+  if (ticks > INT_TICKS - INT_TICKS / 50)
+    /* Check for pending timer interrupt */
+    if (mfp.int_pn_b & (1 << 5))
+      offset = TICK_SIZE;
+
+  ticks = INT_TICKS - ticks;
+  ticks = ticks * 10000L / INT_TICKS;
+
+  return ticks + offset;
+}
+
+
+static void mste_read(struct MSTE_RTC *val)
+{
+#define COPY(v) val->v=(mste_rtc.v & 0xf)
+        do {
+                COPY(sec_ones) ; COPY(sec_tens) ; COPY(min_ones) ;
+                COPY(min_tens) ; COPY(hr_ones) ; COPY(hr_tens) ;
+                COPY(weekday) ; COPY(day_ones) ; COPY(day_tens) ;
+                COPY(mon_ones) ; COPY(mon_tens) ; COPY(year_ones) ;
+                COPY(year_tens) ;
+        /* prevent from reading the clock while it changed */
+        } while (val->sec_ones != (mste_rtc.sec_ones & 0xf));
+#undef COPY
+}
+
+static void mste_write(struct MSTE_RTC *val)
+{
+#define COPY(v) mste_rtc.v=val->v
+        do {
+                COPY(sec_ones) ; COPY(sec_tens) ; COPY(min_ones) ;
+                COPY(min_tens) ; COPY(hr_ones) ; COPY(hr_tens) ;
+                COPY(weekday) ; COPY(day_ones) ; COPY(day_tens) ;
+                COPY(mon_ones) ; COPY(mon_tens) ; COPY(year_ones) ;
+                COPY(year_tens) ;
+        /* prevent from writing the clock while it changed */
+        } while (val->sec_ones != (mste_rtc.sec_ones & 0xf));
+#undef COPY
+}
+
+#define RTC_READ(reg)                           \
+    ({  unsigned char   __val;                  \
+                (void) atari_writeb(reg,&tt_rtc.regsel);        \
+                __val = tt_rtc.data;            \
+                __val;                          \
+        })
+
+#define RTC_WRITE(reg,val)                      \
+    do {                                        \
+                atari_writeb(reg,&tt_rtc.regsel);       \
+                tt_rtc.data = (val);            \
+        } while(0)
+
+
+#define HWCLK_POLL_INTERVAL     5
+
+int atari_mste_hwclk( int op, struct rtc_time *t )
+{
+    int hour, year;
+    int hr24=0;
+    struct MSTE_RTC val;
+
+    mste_rtc.mode=(mste_rtc.mode | 1);
+    hr24=mste_rtc.mon_tens & 1;
+    mste_rtc.mode=(mste_rtc.mode & ~1);
+
+    if (op) {
+        /* write: prepare values */
+
+        val.sec_ones = t->tm_sec % 10;
+        val.sec_tens = t->tm_sec / 10;
+        val.min_ones = t->tm_min % 10;
+        val.min_tens = t->tm_min / 10;
+        hour = t->tm_hour;
+        if (!hr24) {
+            if (hour > 11)
+                hour += 20 - 12;
+            if (hour == 0 || hour == 20)
+                hour += 12;
+        }
+        val.hr_ones = hour % 10;
+        val.hr_tens = hour / 10;
+        val.day_ones = t->tm_mday % 10;
+        val.day_tens = t->tm_mday / 10;
+        val.mon_ones = (t->tm_mon+1) % 10;
+        val.mon_tens = (t->tm_mon+1) / 10;
+        year = t->tm_year - 80;
+        val.year_ones = year % 10;
+        val.year_tens = year / 10;
+        val.weekday = t->tm_wday;
+        mste_write(&val);
+        mste_rtc.mode=(mste_rtc.mode | 1);
+        val.year_ones = (year % 4);     /* leap year register */
+        mste_rtc.mode=(mste_rtc.mode & ~1);
+    }
+    else {
+        mste_read(&val);
+        t->tm_sec = val.sec_ones + val.sec_tens * 10;
+        t->tm_min = val.min_ones + val.min_tens * 10;
+        hour = val.hr_ones + val.hr_tens * 10;
+        if (!hr24) {
+            if (hour == 12 || hour == 12 + 20)
+                hour -= 12;
+            if (hour >= 20)
+                hour += 12 - 20;
+        }
+        t->tm_hour = hour;
+        t->tm_mday = val.day_ones + val.day_tens * 10;
+        t->tm_mon  = val.mon_ones + val.mon_tens * 10 - 1;
+        t->tm_year = val.year_ones + val.year_tens * 10 + 80;
+        t->tm_wday = val.weekday;
+    }
+    return 0;
+}
+
+int atari_tt_hwclk( int op, struct rtc_time *t )
+{
+    int sec=0, min=0, hour=0, day=0, mon=0, year=0, wday=0;
+    unsigned long       flags;
+    unsigned char       ctrl;
+    int pm = 0;
+
+    ctrl = RTC_READ(RTC_CONTROL); /* control registers are
+                                   * independent from the UIP */
+
+    if (op) {
+        /* write: prepare values */
+
+        sec  = t->tm_sec;
+        min  = t->tm_min;
+        hour = t->tm_hour;
+        day  = t->tm_mday;
+        mon  = t->tm_mon + 1;
+        year = t->tm_year - atari_rtc_year_offset;
+        wday = t->tm_wday + (t->tm_wday >= 0);
+
+        if (!(ctrl & RTC_24H)) {
+            if (hour > 11) {
+                pm = 0x80;
+                if (hour != 12)
+                    hour -= 12;
+            }
+            else if (hour == 0)
+                hour = 12;
+        }
+
+        if (!(ctrl & RTC_DM_BINARY)) {
+            BIN_TO_BCD(sec);
+            BIN_TO_BCD(min);
+            BIN_TO_BCD(hour);
+            BIN_TO_BCD(day);
+            BIN_TO_BCD(mon);
+            BIN_TO_BCD(year);
+            if (wday >= 0) BIN_TO_BCD(wday);
+        }
+    }
+
+    /* Reading/writing the clock registers is a bit critical due to
+     * the regular update cycle of the RTC. While an update is in
+     * progress, registers 0..9 shouldn't be touched.
+     * The problem is solved like that: If an update is currently in
+     * progress (the UIP bit is set), the process sleeps for a while
+     * (50ms). This really should be enough, since the update cycle
+     * normally needs 2 ms.
+     * If the UIP bit reads as 0, we have at least 244 usecs until the
+     * update starts. This should be enough... But to be sure,
+     * additionally the RTC_SET bit is set to prevent an update cycle.
+     */
+
+    while( RTC_READ(RTC_FREQ_SELECT) & RTC_UIP ) {
+        current->state = TASK_INTERRUPTIBLE;
+        schedule_timeout(HWCLK_POLL_INTERVAL);
+    }
+
+    local_irq_save(flags);
+    RTC_WRITE( RTC_CONTROL, ctrl | RTC_SET );
+    if (!op) {
+        sec  = RTC_READ( RTC_SECONDS );
+        min  = RTC_READ( RTC_MINUTES );
+        hour = RTC_READ( RTC_HOURS );
+        day  = RTC_READ( RTC_DAY_OF_MONTH );
+        mon  = RTC_READ( RTC_MONTH );
+        year = RTC_READ( RTC_YEAR );
+        wday = RTC_READ( RTC_DAY_OF_WEEK );
+    }
+    else {
+        RTC_WRITE( RTC_SECONDS, sec );
+        RTC_WRITE( RTC_MINUTES, min );
+        RTC_WRITE( RTC_HOURS, hour + pm);
+        RTC_WRITE( RTC_DAY_OF_MONTH, day );
+        RTC_WRITE( RTC_MONTH, mon );
+        RTC_WRITE( RTC_YEAR, year );
+        if (wday >= 0) RTC_WRITE( RTC_DAY_OF_WEEK, wday );
+    }
+    RTC_WRITE( RTC_CONTROL, ctrl & ~RTC_SET );
+    local_irq_restore(flags);
+
+    if (!op) {
+        /* read: adjust values */
+
+        if (hour & 0x80) {
+            hour &= ~0x80;
+            pm = 1;
+        }
+
+        if (!(ctrl & RTC_DM_BINARY)) {
+            BCD_TO_BIN(sec);
+            BCD_TO_BIN(min);
+            BCD_TO_BIN(hour);
+            BCD_TO_BIN(day);
+            BCD_TO_BIN(mon);
+            BCD_TO_BIN(year);
+            BCD_TO_BIN(wday);
+        }
+
+        if (!(ctrl & RTC_24H)) {
+            if (!pm && hour == 12)
+                hour = 0;
+            else if (pm && hour != 12)
+                hour += 12;
+        }
+
+        t->tm_sec  = sec;
+        t->tm_min  = min;
+        t->tm_hour = hour;
+        t->tm_mday = day;
+        t->tm_mon  = mon - 1;
+        t->tm_year = year + atari_rtc_year_offset;
+        t->tm_wday = wday - 1;
+    }
+
+    return( 0 );
+}
+
+
+int atari_mste_set_clock_mmss (unsigned long nowtime)
+{
+    short real_seconds = nowtime % 60, real_minutes = (nowtime / 60) % 60;
+    struct MSTE_RTC val;
+    unsigned char rtc_minutes;
+
+    mste_read(&val);
+    rtc_minutes= val.min_ones + val.min_tens * 10;
+    if ((rtc_minutes < real_minutes
+         ? real_minutes - rtc_minutes
+         : rtc_minutes - real_minutes) < 30)
+    {
+        val.sec_ones = real_seconds % 10;
+        val.sec_tens = real_seconds / 10;
+        val.min_ones = real_minutes % 10;
+        val.min_tens = real_minutes / 10;
+        mste_write(&val);
+    }
+    else
+        return -1;
+    return 0;
+}
+
+int atari_tt_set_clock_mmss (unsigned long nowtime)
+{
+    int retval = 0;
+    short real_seconds = nowtime % 60, real_minutes = (nowtime / 60) % 60;
+    unsigned char save_control, save_freq_select, rtc_minutes;
+
+    save_control = RTC_READ (RTC_CONTROL); /* tell the clock it's being set */
+    RTC_WRITE (RTC_CONTROL, save_control | RTC_SET);
+
+    save_freq_select = RTC_READ (RTC_FREQ_SELECT); /* stop and reset prescaler */
+    RTC_WRITE (RTC_FREQ_SELECT, save_freq_select | RTC_DIV_RESET2);
+
+    rtc_minutes = RTC_READ (RTC_MINUTES);
+    if (!(save_control & RTC_DM_BINARY))
+        BCD_TO_BIN (rtc_minutes);
+
+    /* 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 30 minutes.  */
+    if ((rtc_minutes < real_minutes
+         ? real_minutes - rtc_minutes
+         : rtc_minutes - real_minutes) < 30)
+        {
+            if (!(save_control & RTC_DM_BINARY))
+                {
+                    BIN_TO_BCD (real_seconds);
+                    BIN_TO_BCD (real_minutes);
+                }
+            RTC_WRITE (RTC_SECONDS, real_seconds);
+            RTC_WRITE (RTC_MINUTES, real_minutes);
+        }
+    else
+        retval = -1;
+
+    RTC_WRITE (RTC_FREQ_SELECT, save_freq_select);
+    RTC_WRITE (RTC_CONTROL, save_control);
+    return retval;
+}
+
+/*
+ * Local variables:
+ *  c-indent-level: 4
+ *  tab-width: 8
+ * End:
+ */