summaryrefslogtreecommitdiffstats
path: root/arch/sparc/kernel/time.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/sparc/kernel/time.c')
-rw-r--r--arch/sparc/kernel/time.c641
1 files changed, 641 insertions, 0 deletions
diff --git a/arch/sparc/kernel/time.c b/arch/sparc/kernel/time.c
new file mode 100644
index 0000000..6486cbf
--- /dev/null
+++ b/arch/sparc/kernel/time.c
@@ -0,0 +1,641 @@
+/* $Id: time.c,v 1.60 2002/01/23 14:33:55 davem Exp $
+ * linux/arch/sparc/kernel/time.c
+ *
+ * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
+ * Copyright (C) 1996 Thomas K. Dyas (tdyas@eden.rutgers.edu)
+ *
+ * Chris Davis (cdavis@cois.on.ca) 03/27/1998
+ * Added support for the intersil on the sun4/4200
+ *
+ * Gleb Raiko (rajko@mech.math.msu.su) 08/18/1998
+ * Support for MicroSPARC-IIep, PCI CPU.
+ *
+ * This file handles the Sparc specific time handling details.
+ *
+ * 1997-09-10 Updated NTP code according to technical memorandum Jan '96
+ * "A Kernel Model for Precision Timekeeping" by Dave Mills
+ */
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/param.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/time.h>
+#include <linux/timex.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/ioport.h>
+#include <linux/profile.h>
+
+#include <asm/oplib.h>
+#include <asm/segment.h>
+#include <asm/timer.h>
+#include <asm/mostek.h>
+#include <asm/system.h>
+#include <asm/irq.h>
+#include <asm/io.h>
+#include <asm/idprom.h>
+#include <asm/machines.h>
+#include <asm/sun4paddr.h>
+#include <asm/page.h>
+#include <asm/pcic.h>
+
+extern unsigned long wall_jiffies;
+
+u64 jiffies_64 = INITIAL_JIFFIES;
+
+EXPORT_SYMBOL(jiffies_64);
+
+DEFINE_SPINLOCK(rtc_lock);
+enum sparc_clock_type sp_clock_typ;
+DEFINE_SPINLOCK(mostek_lock);
+void __iomem *mstk48t02_regs = NULL;
+static struct mostek48t08 *mstk48t08_regs = NULL;
+static int set_rtc_mmss(unsigned long);
+static int sbus_do_settimeofday(struct timespec *tv);
+
+#ifdef CONFIG_SUN4
+struct intersil *intersil_clock;
+#define intersil_cmd(intersil_reg, intsil_cmd) intersil_reg->int_cmd_reg = \
+ (intsil_cmd)
+
+#define intersil_intr(intersil_reg, intsil_cmd) intersil_reg->int_intr_reg = \
+ (intsil_cmd)
+
+#define intersil_start(intersil_reg) intersil_cmd(intersil_reg, \
+ ( INTERSIL_START | INTERSIL_32K | INTERSIL_NORMAL | INTERSIL_24H |\
+ INTERSIL_INTR_ENABLE))
+
+#define intersil_stop(intersil_reg) intersil_cmd(intersil_reg, \
+ ( INTERSIL_STOP | INTERSIL_32K | INTERSIL_NORMAL | INTERSIL_24H |\
+ INTERSIL_INTR_ENABLE))
+
+#define intersil_read_intr(intersil_reg, towhere) towhere = \
+ intersil_reg->int_intr_reg
+
+#endif
+
+unsigned long profile_pc(struct pt_regs *regs)
+{
+ extern char __copy_user_begin[], __copy_user_end[];
+ extern char __atomic_begin[], __atomic_end[];
+ extern char __bzero_begin[], __bzero_end[];
+ extern char __bitops_begin[], __bitops_end[];
+
+ unsigned long pc = regs->pc;
+
+ if (in_lock_functions(pc) ||
+ (pc >= (unsigned long) __copy_user_begin &&
+ pc < (unsigned long) __copy_user_end) ||
+ (pc >= (unsigned long) __atomic_begin &&
+ pc < (unsigned long) __atomic_end) ||
+ (pc >= (unsigned long) __bzero_begin &&
+ pc < (unsigned long) __bzero_end) ||
+ (pc >= (unsigned long) __bitops_begin &&
+ pc < (unsigned long) __bitops_end))
+ pc = regs->u_regs[UREG_RETPC];
+ return pc;
+}
+
+__volatile__ unsigned int *master_l10_counter;
+__volatile__ unsigned int *master_l10_limit;
+
+/*
+ * timer_interrupt() needs to keep up the real-time clock,
+ * as well as call the "do_timer()" routine every clocktick
+ */
+
+#define TICK_SIZE (tick_nsec / 1000)
+
+irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs * regs)
+{
+ /* last time the cmos clock got updated */
+ static long last_rtc_update;
+
+#ifndef CONFIG_SMP
+ profile_tick(CPU_PROFILING, regs);
+#endif
+
+ /* Protect counter clear so that do_gettimeoffset works */
+ write_seqlock(&xtime_lock);
+#ifdef CONFIG_SUN4
+ if((idprom->id_machtype == (SM_SUN4 | SM_4_260)) ||
+ (idprom->id_machtype == (SM_SUN4 | SM_4_110))) {
+ int temp;
+ intersil_read_intr(intersil_clock, temp);
+ /* re-enable the irq */
+ enable_pil_irq(10);
+ }
+#endif
+ clear_clock_irq();
+
+ do_timer(regs);
+#ifndef CONFIG_SMP
+ update_process_times(user_mode(regs));
+#endif
+
+
+ /* Determine when to update the Mostek clock. */
+ if ((time_status & STA_UNSYNC) == 0 &&
+ xtime.tv_sec > last_rtc_update + 660 &&
+ (xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 &&
+ (xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 2) {
+ if (set_rtc_mmss(xtime.tv_sec) == 0)
+ last_rtc_update = xtime.tv_sec;
+ else
+ last_rtc_update = xtime.tv_sec - 600; /* do it again in 60 s */
+ }
+ write_sequnlock(&xtime_lock);
+
+ return IRQ_HANDLED;
+}
+
+/* Kick start a stopped clock (procedure from the Sun NVRAM/hostid FAQ). */
+static void __init kick_start_clock(void)
+{
+ struct mostek48t02 *regs = (struct mostek48t02 *)mstk48t02_regs;
+ unsigned char sec;
+ int i, count;
+
+ prom_printf("CLOCK: Clock was stopped. Kick start ");
+
+ spin_lock_irq(&mostek_lock);
+
+ /* Turn on the kick start bit to start the oscillator. */
+ regs->creg |= MSTK_CREG_WRITE;
+ regs->sec &= ~MSTK_STOP;
+ regs->hour |= MSTK_KICK_START;
+ regs->creg &= ~MSTK_CREG_WRITE;
+
+ spin_unlock_irq(&mostek_lock);
+
+ /* Delay to allow the clock oscillator to start. */
+ sec = MSTK_REG_SEC(regs);
+ for (i = 0; i < 3; i++) {
+ while (sec == MSTK_REG_SEC(regs))
+ for (count = 0; count < 100000; count++)
+ /* nothing */ ;
+ prom_printf(".");
+ sec = regs->sec;
+ }
+ prom_printf("\n");
+
+ spin_lock_irq(&mostek_lock);
+
+ /* Turn off kick start and set a "valid" time and date. */
+ regs->creg |= MSTK_CREG_WRITE;
+ regs->hour &= ~MSTK_KICK_START;
+ MSTK_SET_REG_SEC(regs,0);
+ MSTK_SET_REG_MIN(regs,0);
+ MSTK_SET_REG_HOUR(regs,0);
+ MSTK_SET_REG_DOW(regs,5);
+ MSTK_SET_REG_DOM(regs,1);
+ MSTK_SET_REG_MONTH(regs,8);
+ MSTK_SET_REG_YEAR(regs,1996 - MSTK_YEAR_ZERO);
+ regs->creg &= ~MSTK_CREG_WRITE;
+
+ spin_unlock_irq(&mostek_lock);
+
+ /* Ensure the kick start bit is off. If it isn't, turn it off. */
+ while (regs->hour & MSTK_KICK_START) {
+ prom_printf("CLOCK: Kick start still on!\n");
+
+ spin_lock_irq(&mostek_lock);
+ regs->creg |= MSTK_CREG_WRITE;
+ regs->hour &= ~MSTK_KICK_START;
+ regs->creg &= ~MSTK_CREG_WRITE;
+ spin_unlock_irq(&mostek_lock);
+ }
+
+ prom_printf("CLOCK: Kick start procedure successful.\n");
+}
+
+/* Return nonzero if the clock chip battery is low. */
+static __inline__ int has_low_battery(void)
+{
+ struct mostek48t02 *regs = (struct mostek48t02 *)mstk48t02_regs;
+ unsigned char data1, data2;
+
+ spin_lock_irq(&mostek_lock);
+ data1 = regs->eeprom[0]; /* Read some data. */
+ regs->eeprom[0] = ~data1; /* Write back the complement. */
+ data2 = regs->eeprom[0]; /* Read back the complement. */
+ regs->eeprom[0] = data1; /* Restore the original value. */
+ spin_unlock_irq(&mostek_lock);
+
+ return (data1 == data2); /* Was the write blocked? */
+}
+
+/* Probe for the real time clock chip on Sun4 */
+static __inline__ void sun4_clock_probe(void)
+{
+#ifdef CONFIG_SUN4
+ int temp;
+ struct resource r;
+
+ memset(&r, 0, sizeof(r));
+ if( idprom->id_machtype == (SM_SUN4 | SM_4_330) ) {
+ sp_clock_typ = MSTK48T02;
+ r.start = sun4_clock_physaddr;
+ mstk48t02_regs = sbus_ioremap(&r, 0,
+ sizeof(struct mostek48t02), NULL);
+ mstk48t08_regs = NULL; /* To catch weirdness */
+ intersil_clock = NULL; /* just in case */
+
+ /* Kick start the clock if it is completely stopped. */
+ if (mostek_read(mstk48t02_regs + MOSTEK_SEC) & MSTK_STOP)
+ kick_start_clock();
+ } else if( idprom->id_machtype == (SM_SUN4 | SM_4_260)) {
+ /* intersil setup code */
+ printk("Clock: INTERSIL at %8x ",sun4_clock_physaddr);
+ sp_clock_typ = INTERSIL;
+ r.start = sun4_clock_physaddr;
+ intersil_clock = (struct intersil *)
+ sbus_ioremap(&r, 0, sizeof(*intersil_clock), "intersil");
+ mstk48t02_regs = 0; /* just be sure */
+ mstk48t08_regs = NULL; /* ditto */
+ /* initialise the clock */
+
+ intersil_intr(intersil_clock,INTERSIL_INT_100HZ);
+
+ intersil_start(intersil_clock);
+
+ intersil_read_intr(intersil_clock, temp);
+ while (!(temp & 0x80))
+ intersil_read_intr(intersil_clock, temp);
+
+ intersil_read_intr(intersil_clock, temp);
+ while (!(temp & 0x80))
+ intersil_read_intr(intersil_clock, temp);
+
+ intersil_stop(intersil_clock);
+
+ }
+#endif
+}
+
+/* Probe for the mostek real time clock chip. */
+static __inline__ void clock_probe(void)
+{
+ struct linux_prom_registers clk_reg[2];
+ char model[128];
+ register int node, cpuunit, bootbus;
+ struct resource r;
+
+ cpuunit = bootbus = 0;
+ memset(&r, 0, sizeof(r));
+
+ /* Determine the correct starting PROM node for the probe. */
+ node = prom_getchild(prom_root_node);
+ switch (sparc_cpu_model) {
+ case sun4c:
+ break;
+ case sun4m:
+ node = prom_getchild(prom_searchsiblings(node, "obio"));
+ break;
+ case sun4d:
+ node = prom_getchild(bootbus = prom_searchsiblings(prom_getchild(cpuunit = prom_searchsiblings(node, "cpu-unit")), "bootbus"));
+ break;
+ default:
+ prom_printf("CLOCK: Unsupported architecture!\n");
+ prom_halt();
+ }
+
+ /* Find the PROM node describing the real time clock. */
+ sp_clock_typ = MSTK_INVALID;
+ node = prom_searchsiblings(node,"eeprom");
+ if (!node) {
+ prom_printf("CLOCK: No clock found!\n");
+ prom_halt();
+ }
+
+ /* Get the model name and setup everything up. */
+ model[0] = '\0';
+ prom_getstring(node, "model", model, sizeof(model));
+ if (strcmp(model, "mk48t02") == 0) {
+ sp_clock_typ = MSTK48T02;
+ if (prom_getproperty(node, "reg", (char *) clk_reg, sizeof(clk_reg)) == -1) {
+ prom_printf("clock_probe: FAILED!\n");
+ prom_halt();
+ }
+ if (sparc_cpu_model == sun4d)
+ prom_apply_generic_ranges (bootbus, cpuunit, clk_reg, 1);
+ else
+ prom_apply_obio_ranges(clk_reg, 1);
+ /* Map the clock register io area read-only */
+ r.flags = clk_reg[0].which_io;
+ r.start = clk_reg[0].phys_addr;
+ mstk48t02_regs = sbus_ioremap(&r, 0,
+ sizeof(struct mostek48t02), "mk48t02");
+ mstk48t08_regs = NULL; /* To catch weirdness */
+ } else if (strcmp(model, "mk48t08") == 0) {
+ sp_clock_typ = MSTK48T08;
+ if(prom_getproperty(node, "reg", (char *) clk_reg,
+ sizeof(clk_reg)) == -1) {
+ prom_printf("clock_probe: FAILED!\n");
+ prom_halt();
+ }
+ if (sparc_cpu_model == sun4d)
+ prom_apply_generic_ranges (bootbus, cpuunit, clk_reg, 1);
+ else
+ prom_apply_obio_ranges(clk_reg, 1);
+ /* Map the clock register io area read-only */
+ /* XXX r/o attribute is somewhere in r.flags */
+ r.flags = clk_reg[0].which_io;
+ r.start = clk_reg[0].phys_addr;
+ mstk48t08_regs = (struct mostek48t08 *) sbus_ioremap(&r, 0,
+ sizeof(struct mostek48t08), "mk48t08");
+
+ mstk48t02_regs = &mstk48t08_regs->regs;
+ } else {
+ prom_printf("CLOCK: Unknown model name '%s'\n",model);
+ prom_halt();
+ }
+
+ /* Report a low battery voltage condition. */
+ if (has_low_battery())
+ printk(KERN_CRIT "NVRAM: Low battery voltage!\n");
+
+ /* Kick start the clock if it is completely stopped. */
+ if (mostek_read(mstk48t02_regs + MOSTEK_SEC) & MSTK_STOP)
+ kick_start_clock();
+}
+
+void __init sbus_time_init(void)
+{
+ unsigned int year, mon, day, hour, min, sec;
+ struct mostek48t02 *mregs;
+
+#ifdef CONFIG_SUN4
+ int temp;
+ struct intersil *iregs;
+#endif
+
+ BTFIXUPSET_CALL(bus_do_settimeofday, sbus_do_settimeofday, BTFIXUPCALL_NORM);
+ btfixup();
+
+ if (ARCH_SUN4)
+ sun4_clock_probe();
+ else
+ clock_probe();
+
+ sparc_init_timers(timer_interrupt);
+
+#ifdef CONFIG_SUN4
+ if(idprom->id_machtype == (SM_SUN4 | SM_4_330)) {
+#endif
+ mregs = (struct mostek48t02 *)mstk48t02_regs;
+ if(!mregs) {
+ prom_printf("Something wrong, clock regs not mapped yet.\n");
+ prom_halt();
+ }
+ spin_lock_irq(&mostek_lock);
+ mregs->creg |= MSTK_CREG_READ;
+ sec = MSTK_REG_SEC(mregs);
+ min = MSTK_REG_MIN(mregs);
+ hour = MSTK_REG_HOUR(mregs);
+ day = MSTK_REG_DOM(mregs);
+ mon = MSTK_REG_MONTH(mregs);
+ year = MSTK_CVT_YEAR( MSTK_REG_YEAR(mregs) );
+ xtime.tv_sec = mktime(year, mon, day, hour, min, sec);
+ xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
+ set_normalized_timespec(&wall_to_monotonic,
+ -xtime.tv_sec, -xtime.tv_nsec);
+ mregs->creg &= ~MSTK_CREG_READ;
+ spin_unlock_irq(&mostek_lock);
+#ifdef CONFIG_SUN4
+ } else if(idprom->id_machtype == (SM_SUN4 | SM_4_260) ) {
+ /* initialise the intersil on sun4 */
+
+ iregs=intersil_clock;
+ if(!iregs) {
+ prom_printf("Something wrong, clock regs not mapped yet.\n");
+ prom_halt();
+ }
+
+ intersil_intr(intersil_clock,INTERSIL_INT_100HZ);
+ disable_pil_irq(10);
+ intersil_stop(iregs);
+ intersil_read_intr(intersil_clock, temp);
+
+ temp = iregs->clk.int_csec;
+
+ sec = iregs->clk.int_sec;
+ min = iregs->clk.int_min;
+ hour = iregs->clk.int_hour;
+ day = iregs->clk.int_day;
+ mon = iregs->clk.int_month;
+ year = MSTK_CVT_YEAR(iregs->clk.int_year);
+
+ enable_pil_irq(10);
+ intersil_start(iregs);
+
+ xtime.tv_sec = mktime(year, mon, day, hour, min, sec);
+ xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
+ set_normalized_timespec(&wall_to_monotonic,
+ -xtime.tv_sec, -xtime.tv_nsec);
+ printk("%u/%u/%u %u:%u:%u\n",day,mon,year,hour,min,sec);
+ }
+#endif
+
+ /* Now that OBP ticker has been silenced, it is safe to enable IRQ. */
+ local_irq_enable();
+}
+
+void __init time_init(void)
+{
+#ifdef CONFIG_PCI
+ extern void pci_time_init(void);
+ if (pcic_present()) {
+ pci_time_init();
+ return;
+ }
+#endif
+ sbus_time_init();
+}
+
+extern __inline__ unsigned long do_gettimeoffset(void)
+{
+ return (*master_l10_counter >> 10) & 0x1fffff;
+}
+
+/*
+ * Returns nanoseconds
+ * XXX This is a suboptimal implementation.
+ */
+unsigned long long sched_clock(void)
+{
+ return (unsigned long long)jiffies * (1000000000 / HZ);
+}
+
+/* Ok, my cute asm atomicity trick doesn't work anymore.
+ * There are just too many variables that need to be protected
+ * now (both members of xtime, wall_jiffies, et al.)
+ */
+void do_gettimeofday(struct timeval *tv)
+{
+ unsigned long flags;
+ unsigned long seq;
+ unsigned long usec, sec;
+ unsigned long max_ntp_tick = tick_usec - tickadj;
+
+ do {
+ unsigned long lost;
+
+ seq = read_seqbegin_irqsave(&xtime_lock, flags);
+ usec = do_gettimeoffset();
+ lost = jiffies - wall_jiffies;
+
+ /*
+ * If time_adjust is negative then NTP is slowing the clock
+ * so make sure not to go into next possible interval.
+ * Better to lose some accuracy than have time go backwards..
+ */
+ if (unlikely(time_adjust < 0)) {
+ usec = min(usec, max_ntp_tick);
+
+ if (lost)
+ usec += lost * max_ntp_tick;
+ }
+ else if (unlikely(lost))
+ usec += lost * tick_usec;
+
+ sec = xtime.tv_sec;
+ usec += (xtime.tv_nsec / 1000);
+ } while (read_seqretry_irqrestore(&xtime_lock, seq, flags));
+
+ while (usec >= 1000000) {
+ usec -= 1000000;
+ sec++;
+ }
+
+ tv->tv_sec = sec;
+ tv->tv_usec = usec;
+}
+
+EXPORT_SYMBOL(do_gettimeofday);
+
+int do_settimeofday(struct timespec *tv)
+{
+ int ret;
+
+ write_seqlock_irq(&xtime_lock);
+ ret = bus_do_settimeofday(tv);
+ write_sequnlock_irq(&xtime_lock);
+ clock_was_set();
+ return ret;
+}
+
+EXPORT_SYMBOL(do_settimeofday);
+
+static int sbus_do_settimeofday(struct timespec *tv)
+{
+ time_t wtm_sec, sec = tv->tv_sec;
+ long wtm_nsec, nsec = tv->tv_nsec;
+
+ if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
+ return -EINVAL;
+
+ /*
+ * This is revolting. We need to set "xtime" correctly. However, the
+ * value in this location is the value at the most recent update of
+ * wall time. Discover what correction gettimeofday() would have
+ * made, and then undo it!
+ */
+ nsec -= 1000 * (do_gettimeoffset() +
+ (jiffies - wall_jiffies) * (USEC_PER_SEC / HZ));
+
+ wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec);
+ wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec);
+
+ set_normalized_timespec(&xtime, sec, nsec);
+ set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);
+
+ time_adjust = 0; /* stop active adjtime() */
+ time_status |= STA_UNSYNC;
+ time_maxerror = NTP_PHASE_LIMIT;
+ time_esterror = NTP_PHASE_LIMIT;
+ return 0;
+}
+
+/*
+ * BUG: This routine does not handle hour overflow properly; it just
+ * sets the minutes. Usually you won't notice until after reboot!
+ */
+static int set_rtc_mmss(unsigned long nowtime)
+{
+ int real_seconds, real_minutes, mostek_minutes;
+ struct mostek48t02 *regs = (struct mostek48t02 *)mstk48t02_regs;
+ unsigned long flags;
+#ifdef CONFIG_SUN4
+ struct intersil *iregs = intersil_clock;
+ int temp;
+#endif
+
+ /* Not having a register set can lead to trouble. */
+ if (!regs) {
+#ifdef CONFIG_SUN4
+ if(!iregs)
+ return -1;
+ else {
+ temp = iregs->clk.int_csec;
+
+ mostek_minutes = iregs->clk.int_min;
+
+ real_seconds = nowtime % 60;
+ real_minutes = nowtime / 60;
+ if (((abs(real_minutes - mostek_minutes) + 15)/30) & 1)
+ real_minutes += 30; /* correct for half hour time zone */
+ real_minutes %= 60;
+
+ if (abs(real_minutes - mostek_minutes) < 30) {
+ intersil_stop(iregs);
+ iregs->clk.int_sec=real_seconds;
+ iregs->clk.int_min=real_minutes;
+ intersil_start(iregs);
+ } else {
+ printk(KERN_WARNING
+ "set_rtc_mmss: can't update from %d to %d\n",
+ mostek_minutes, real_minutes);
+ return -1;
+ }
+
+ return 0;
+ }
+#endif
+ }
+
+ spin_lock_irqsave(&mostek_lock, flags);
+ /* Read the current RTC minutes. */
+ regs->creg |= MSTK_CREG_READ;
+ mostek_minutes = MSTK_REG_MIN(regs);
+ regs->creg &= ~MSTK_CREG_READ;
+
+ /*
+ * 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 - mostek_minutes) + 15)/30) & 1)
+ real_minutes += 30; /* correct for half hour time zone */
+ real_minutes %= 60;
+
+ if (abs(real_minutes - mostek_minutes) < 30) {
+ regs->creg |= MSTK_CREG_WRITE;
+ MSTK_SET_REG_SEC(regs,real_seconds);
+ MSTK_SET_REG_MIN(regs,real_minutes);
+ regs->creg &= ~MSTK_CREG_WRITE;
+ spin_unlock_irqrestore(&mostek_lock, flags);
+ return 0;
+ } else {
+ spin_unlock_irqrestore(&mostek_lock, flags);
+ return -1;
+ }
+}
OpenPOWER on IntegriCloud