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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/sparc64/kernel/time.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/sparc64/kernel/time.c')
-rw-r--r--arch/sparc64/kernel/time.c1195
1 files changed, 1195 insertions, 0 deletions
diff --git a/arch/sparc64/kernel/time.c b/arch/sparc64/kernel/time.c
new file mode 100644
index 000000000000..6a717d4d2bc5
--- /dev/null
+++ b/arch/sparc64/kernel/time.c
@@ -0,0 +1,1195 @@
+/* $Id: time.c,v 1.42 2002/01/23 14:33:55 davem Exp $
+ * time.c: UltraSparc timer and TOD clock support.
+ *
+ * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
+ * Copyright (C) 1998 Eddie C. Dost (ecd@skynet.be)
+ *
+ * Based largely on code which is:
+ *
+ * Copyright (C) 1996 Thomas K. Dyas (tdyas@eden.rutgers.edu)
+ */
+
+#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/ioport.h>
+#include <linux/mc146818rtc.h>
+#include <linux/delay.h>
+#include <linux/profile.h>
+#include <linux/bcd.h>
+#include <linux/jiffies.h>
+#include <linux/cpufreq.h>
+#include <linux/percpu.h>
+#include <linux/profile.h>
+
+#include <asm/oplib.h>
+#include <asm/mostek.h>
+#include <asm/timer.h>
+#include <asm/irq.h>
+#include <asm/io.h>
+#include <asm/sbus.h>
+#include <asm/fhc.h>
+#include <asm/pbm.h>
+#include <asm/ebus.h>
+#include <asm/isa.h>
+#include <asm/starfire.h>
+#include <asm/smp.h>
+#include <asm/sections.h>
+#include <asm/cpudata.h>
+
+DEFINE_SPINLOCK(mostek_lock);
+DEFINE_SPINLOCK(rtc_lock);
+unsigned long mstk48t02_regs = 0UL;
+#ifdef CONFIG_PCI
+unsigned long ds1287_regs = 0UL;
+#endif
+
+extern unsigned long wall_jiffies;
+
+u64 jiffies_64 = INITIAL_JIFFIES;
+
+EXPORT_SYMBOL(jiffies_64);
+
+static unsigned long mstk48t08_regs = 0UL;
+static unsigned long mstk48t59_regs = 0UL;
+
+static int set_rtc_mmss(unsigned long);
+
+static __init unsigned long dummy_get_tick(void)
+{
+ return 0;
+}
+
+static __initdata struct sparc64_tick_ops dummy_tick_ops = {
+ .get_tick = dummy_get_tick,
+};
+
+struct sparc64_tick_ops *tick_ops = &dummy_tick_ops;
+
+#define TICK_PRIV_BIT (1UL << 63)
+
+#ifdef CONFIG_SMP
+unsigned long profile_pc(struct pt_regs *regs)
+{
+ unsigned long pc = instruction_pointer(regs);
+
+ if (in_lock_functions(pc))
+ return regs->u_regs[UREG_RETPC];
+ return pc;
+}
+EXPORT_SYMBOL(profile_pc);
+#endif
+
+static void tick_disable_protection(void)
+{
+ /* Set things up so user can access tick register for profiling
+ * purposes. Also workaround BB_ERRATA_1 by doing a dummy
+ * read back of %tick after writing it.
+ */
+ __asm__ __volatile__(
+ " ba,pt %%xcc, 1f\n"
+ " nop\n"
+ " .align 64\n"
+ "1: rd %%tick, %%g2\n"
+ " add %%g2, 6, %%g2\n"
+ " andn %%g2, %0, %%g2\n"
+ " wrpr %%g2, 0, %%tick\n"
+ " rdpr %%tick, %%g0"
+ : /* no outputs */
+ : "r" (TICK_PRIV_BIT)
+ : "g2");
+}
+
+static void tick_init_tick(unsigned long offset)
+{
+ tick_disable_protection();
+
+ __asm__ __volatile__(
+ " rd %%tick, %%g1\n"
+ " andn %%g1, %1, %%g1\n"
+ " ba,pt %%xcc, 1f\n"
+ " add %%g1, %0, %%g1\n"
+ " .align 64\n"
+ "1: wr %%g1, 0x0, %%tick_cmpr\n"
+ " rd %%tick_cmpr, %%g0"
+ : /* no outputs */
+ : "r" (offset), "r" (TICK_PRIV_BIT)
+ : "g1");
+}
+
+static unsigned long tick_get_tick(void)
+{
+ unsigned long ret;
+
+ __asm__ __volatile__("rd %%tick, %0\n\t"
+ "mov %0, %0"
+ : "=r" (ret));
+
+ return ret & ~TICK_PRIV_BIT;
+}
+
+static unsigned long tick_get_compare(void)
+{
+ unsigned long ret;
+
+ __asm__ __volatile__("rd %%tick_cmpr, %0\n\t"
+ "mov %0, %0"
+ : "=r" (ret));
+
+ return ret;
+}
+
+static unsigned long tick_add_compare(unsigned long adj)
+{
+ unsigned long new_compare;
+
+ /* Workaround for Spitfire Errata (#54 I think??), I discovered
+ * this via Sun BugID 4008234, mentioned in Solaris-2.5.1 patch
+ * number 103640.
+ *
+ * On Blackbird writes to %tick_cmpr can fail, the
+ * workaround seems to be to execute the wr instruction
+ * at the start of an I-cache line, and perform a dummy
+ * read back from %tick_cmpr right after writing to it. -DaveM
+ */
+ __asm__ __volatile__("rd %%tick_cmpr, %0\n\t"
+ "ba,pt %%xcc, 1f\n\t"
+ " add %0, %1, %0\n\t"
+ ".align 64\n"
+ "1:\n\t"
+ "wr %0, 0, %%tick_cmpr\n\t"
+ "rd %%tick_cmpr, %%g0"
+ : "=&r" (new_compare)
+ : "r" (adj));
+
+ return new_compare;
+}
+
+static unsigned long tick_add_tick(unsigned long adj, unsigned long offset)
+{
+ unsigned long new_tick, tmp;
+
+ /* Also need to handle Blackbird bug here too. */
+ __asm__ __volatile__("rd %%tick, %0\n\t"
+ "add %0, %2, %0\n\t"
+ "wrpr %0, 0, %%tick\n\t"
+ "andn %0, %4, %1\n\t"
+ "ba,pt %%xcc, 1f\n\t"
+ " add %1, %3, %1\n\t"
+ ".align 64\n"
+ "1:\n\t"
+ "wr %1, 0, %%tick_cmpr\n\t"
+ "rd %%tick_cmpr, %%g0"
+ : "=&r" (new_tick), "=&r" (tmp)
+ : "r" (adj), "r" (offset), "r" (TICK_PRIV_BIT));
+
+ return new_tick;
+}
+
+static struct sparc64_tick_ops tick_operations = {
+ .init_tick = tick_init_tick,
+ .get_tick = tick_get_tick,
+ .get_compare = tick_get_compare,
+ .add_tick = tick_add_tick,
+ .add_compare = tick_add_compare,
+ .softint_mask = 1UL << 0,
+};
+
+static void stick_init_tick(unsigned long offset)
+{
+ tick_disable_protection();
+
+ /* Let the user get at STICK too. */
+ __asm__ __volatile__(
+ " rd %%asr24, %%g2\n"
+ " andn %%g2, %0, %%g2\n"
+ " wr %%g2, 0, %%asr24"
+ : /* no outputs */
+ : "r" (TICK_PRIV_BIT)
+ : "g1", "g2");
+
+ __asm__ __volatile__(
+ " rd %%asr24, %%g1\n"
+ " andn %%g1, %1, %%g1\n"
+ " add %%g1, %0, %%g1\n"
+ " wr %%g1, 0x0, %%asr25"
+ : /* no outputs */
+ : "r" (offset), "r" (TICK_PRIV_BIT)
+ : "g1");
+}
+
+static unsigned long stick_get_tick(void)
+{
+ unsigned long ret;
+
+ __asm__ __volatile__("rd %%asr24, %0"
+ : "=r" (ret));
+
+ return ret & ~TICK_PRIV_BIT;
+}
+
+static unsigned long stick_get_compare(void)
+{
+ unsigned long ret;
+
+ __asm__ __volatile__("rd %%asr25, %0"
+ : "=r" (ret));
+
+ return ret;
+}
+
+static unsigned long stick_add_tick(unsigned long adj, unsigned long offset)
+{
+ unsigned long new_tick, tmp;
+
+ __asm__ __volatile__("rd %%asr24, %0\n\t"
+ "add %0, %2, %0\n\t"
+ "wr %0, 0, %%asr24\n\t"
+ "andn %0, %4, %1\n\t"
+ "add %1, %3, %1\n\t"
+ "wr %1, 0, %%asr25"
+ : "=&r" (new_tick), "=&r" (tmp)
+ : "r" (adj), "r" (offset), "r" (TICK_PRIV_BIT));
+
+ return new_tick;
+}
+
+static unsigned long stick_add_compare(unsigned long adj)
+{
+ unsigned long new_compare;
+
+ __asm__ __volatile__("rd %%asr25, %0\n\t"
+ "add %0, %1, %0\n\t"
+ "wr %0, 0, %%asr25"
+ : "=&r" (new_compare)
+ : "r" (adj));
+
+ return new_compare;
+}
+
+static struct sparc64_tick_ops stick_operations = {
+ .init_tick = stick_init_tick,
+ .get_tick = stick_get_tick,
+ .get_compare = stick_get_compare,
+ .add_tick = stick_add_tick,
+ .add_compare = stick_add_compare,
+ .softint_mask = 1UL << 16,
+};
+
+/* On Hummingbird the STICK/STICK_CMPR register is implemented
+ * in I/O space. There are two 64-bit registers each, the
+ * first holds the low 32-bits of the value and the second holds
+ * the high 32-bits.
+ *
+ * Since STICK is constantly updating, we have to access it carefully.
+ *
+ * The sequence we use to read is:
+ * 1) read low
+ * 2) read high
+ * 3) read low again, if it rolled over increment high by 1
+ *
+ * Writing STICK safely is also tricky:
+ * 1) write low to zero
+ * 2) write high
+ * 3) write low
+ */
+#define HBIRD_STICKCMP_ADDR 0x1fe0000f060UL
+#define HBIRD_STICK_ADDR 0x1fe0000f070UL
+
+static unsigned long __hbird_read_stick(void)
+{
+ unsigned long ret, tmp1, tmp2, tmp3;
+ unsigned long addr = HBIRD_STICK_ADDR;
+
+ __asm__ __volatile__("ldxa [%1] %5, %2\n\t"
+ "add %1, 0x8, %1\n\t"
+ "ldxa [%1] %5, %3\n\t"
+ "sub %1, 0x8, %1\n\t"
+ "ldxa [%1] %5, %4\n\t"
+ "cmp %4, %2\n\t"
+ "blu,a,pn %%xcc, 1f\n\t"
+ " add %3, 1, %3\n"
+ "1:\n\t"
+ "sllx %3, 32, %3\n\t"
+ "or %3, %4, %0\n\t"
+ : "=&r" (ret), "=&r" (addr),
+ "=&r" (tmp1), "=&r" (tmp2), "=&r" (tmp3)
+ : "i" (ASI_PHYS_BYPASS_EC_E), "1" (addr));
+
+ return ret;
+}
+
+static unsigned long __hbird_read_compare(void)
+{
+ unsigned long low, high;
+ unsigned long addr = HBIRD_STICKCMP_ADDR;
+
+ __asm__ __volatile__("ldxa [%2] %3, %0\n\t"
+ "add %2, 0x8, %2\n\t"
+ "ldxa [%2] %3, %1"
+ : "=&r" (low), "=&r" (high), "=&r" (addr)
+ : "i" (ASI_PHYS_BYPASS_EC_E), "2" (addr));
+
+ return (high << 32UL) | low;
+}
+
+static void __hbird_write_stick(unsigned long val)
+{
+ unsigned long low = (val & 0xffffffffUL);
+ unsigned long high = (val >> 32UL);
+ unsigned long addr = HBIRD_STICK_ADDR;
+
+ __asm__ __volatile__("stxa %%g0, [%0] %4\n\t"
+ "add %0, 0x8, %0\n\t"
+ "stxa %3, [%0] %4\n\t"
+ "sub %0, 0x8, %0\n\t"
+ "stxa %2, [%0] %4"
+ : "=&r" (addr)
+ : "0" (addr), "r" (low), "r" (high),
+ "i" (ASI_PHYS_BYPASS_EC_E));
+}
+
+static void __hbird_write_compare(unsigned long val)
+{
+ unsigned long low = (val & 0xffffffffUL);
+ unsigned long high = (val >> 32UL);
+ unsigned long addr = HBIRD_STICKCMP_ADDR + 0x8UL;
+
+ __asm__ __volatile__("stxa %3, [%0] %4\n\t"
+ "sub %0, 0x8, %0\n\t"
+ "stxa %2, [%0] %4"
+ : "=&r" (addr)
+ : "0" (addr), "r" (low), "r" (high),
+ "i" (ASI_PHYS_BYPASS_EC_E));
+}
+
+static void hbtick_init_tick(unsigned long offset)
+{
+ unsigned long val;
+
+ tick_disable_protection();
+
+ /* XXX This seems to be necessary to 'jumpstart' Hummingbird
+ * XXX into actually sending STICK interrupts. I think because
+ * XXX of how we store %tick_cmpr in head.S this somehow resets the
+ * XXX {TICK + STICK} interrupt mux. -DaveM
+ */
+ __hbird_write_stick(__hbird_read_stick());
+
+ val = __hbird_read_stick() & ~TICK_PRIV_BIT;
+ __hbird_write_compare(val + offset);
+}
+
+static unsigned long hbtick_get_tick(void)
+{
+ return __hbird_read_stick() & ~TICK_PRIV_BIT;
+}
+
+static unsigned long hbtick_get_compare(void)
+{
+ return __hbird_read_compare();
+}
+
+static unsigned long hbtick_add_tick(unsigned long adj, unsigned long offset)
+{
+ unsigned long val;
+
+ val = __hbird_read_stick() + adj;
+ __hbird_write_stick(val);
+
+ val &= ~TICK_PRIV_BIT;
+ __hbird_write_compare(val + offset);
+
+ return val;
+}
+
+static unsigned long hbtick_add_compare(unsigned long adj)
+{
+ unsigned long val = __hbird_read_compare() + adj;
+
+ val &= ~TICK_PRIV_BIT;
+ __hbird_write_compare(val);
+
+ return val;
+}
+
+static struct sparc64_tick_ops hbtick_operations = {
+ .init_tick = hbtick_init_tick,
+ .get_tick = hbtick_get_tick,
+ .get_compare = hbtick_get_compare,
+ .add_tick = hbtick_add_tick,
+ .add_compare = hbtick_add_compare,
+ .softint_mask = 1UL << 0,
+};
+
+/* timer_interrupt() needs to keep up the real-time clock,
+ * as well as call the "do_timer()" routine every clocktick
+ *
+ * NOTE: On SUN5 systems the ticker interrupt comes in using 2
+ * interrupts, one at level14 and one with softint bit 0.
+ */
+unsigned long timer_tick_offset;
+unsigned long timer_tick_compare;
+
+static unsigned long timer_ticks_per_nsec_quotient;
+
+#define TICK_SIZE (tick_nsec / 1000)
+
+static inline void timer_check_rtc(void)
+{
+ /* last time the cmos clock got updated */
+ static long last_rtc_update;
+
+ /* 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 */
+ }
+}
+
+static irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs * regs)
+{
+ unsigned long ticks, pstate;
+
+ write_seqlock(&xtime_lock);
+
+ do {
+#ifndef CONFIG_SMP
+ profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(regs));
+#endif
+ do_timer(regs);
+
+ /* Guarantee that the following sequences execute
+ * uninterrupted.
+ */
+ __asm__ __volatile__("rdpr %%pstate, %0\n\t"
+ "wrpr %0, %1, %%pstate"
+ : "=r" (pstate)
+ : "i" (PSTATE_IE));
+
+ timer_tick_compare = tick_ops->add_compare(timer_tick_offset);
+ ticks = tick_ops->get_tick();
+
+ /* Restore PSTATE_IE. */
+ __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
+ : /* no outputs */
+ : "r" (pstate));
+ } while (time_after_eq(ticks, timer_tick_compare));
+
+ timer_check_rtc();
+
+ write_sequnlock(&xtime_lock);
+
+ return IRQ_HANDLED;
+}
+
+#ifdef CONFIG_SMP
+void timer_tick_interrupt(struct pt_regs *regs)
+{
+ write_seqlock(&xtime_lock);
+
+ do_timer(regs);
+
+ /*
+ * Only keep timer_tick_offset uptodate, but don't set TICK_CMPR.
+ */
+ timer_tick_compare = tick_ops->get_compare() + timer_tick_offset;
+
+ timer_check_rtc();
+
+ write_sequnlock(&xtime_lock);
+}
+#endif
+
+/* Kick start a stopped clock (procedure from the Sun NVRAM/hostid FAQ). */
+static void __init kick_start_clock(void)
+{
+ unsigned long regs = mstk48t02_regs;
+ u8 sec, tmp;
+ 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. */
+ tmp = mostek_read(regs + MOSTEK_CREG);
+ tmp |= MSTK_CREG_WRITE;
+ mostek_write(regs + MOSTEK_CREG, tmp);
+ tmp = mostek_read(regs + MOSTEK_SEC);
+ tmp &= ~MSTK_STOP;
+ mostek_write(regs + MOSTEK_SEC, tmp);
+ tmp = mostek_read(regs + MOSTEK_HOUR);
+ tmp |= MSTK_KICK_START;
+ mostek_write(regs + MOSTEK_HOUR, tmp);
+ tmp = mostek_read(regs + MOSTEK_CREG);
+ tmp &= ~MSTK_CREG_WRITE;
+ mostek_write(regs + MOSTEK_CREG, tmp);
+
+ 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 = MSTK_REG_SEC(regs);
+ }
+ prom_printf("\n");
+
+ spin_lock_irq(&mostek_lock);
+
+ /* Turn off kick start and set a "valid" time and date. */
+ tmp = mostek_read(regs + MOSTEK_CREG);
+ tmp |= MSTK_CREG_WRITE;
+ mostek_write(regs + MOSTEK_CREG, tmp);
+ tmp = mostek_read(regs + MOSTEK_HOUR);
+ tmp &= ~MSTK_KICK_START;
+ mostek_write(regs + MOSTEK_HOUR, tmp);
+ 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);
+ tmp = mostek_read(regs + MOSTEK_CREG);
+ tmp &= ~MSTK_CREG_WRITE;
+ mostek_write(regs + MOSTEK_CREG, tmp);
+
+ spin_unlock_irq(&mostek_lock);
+
+ /* Ensure the kick start bit is off. If it isn't, turn it off. */
+ while (mostek_read(regs + MOSTEK_HOUR) & MSTK_KICK_START) {
+ prom_printf("CLOCK: Kick start still on!\n");
+
+ spin_lock_irq(&mostek_lock);
+
+ tmp = mostek_read(regs + MOSTEK_CREG);
+ tmp |= MSTK_CREG_WRITE;
+ mostek_write(regs + MOSTEK_CREG, tmp);
+
+ tmp = mostek_read(regs + MOSTEK_HOUR);
+ tmp &= ~MSTK_KICK_START;
+ mostek_write(regs + MOSTEK_HOUR, tmp);
+
+ tmp = mostek_read(regs + MOSTEK_CREG);
+ tmp &= ~MSTK_CREG_WRITE;
+ mostek_write(regs + MOSTEK_CREG, tmp);
+
+ spin_unlock_irq(&mostek_lock);
+ }
+
+ prom_printf("CLOCK: Kick start procedure successful.\n");
+}
+
+/* Return nonzero if the clock chip battery is low. */
+static int __init has_low_battery(void)
+{
+ unsigned long regs = mstk48t02_regs;
+ u8 data1, data2;
+
+ spin_lock_irq(&mostek_lock);
+
+ data1 = mostek_read(regs + MOSTEK_EEPROM); /* Read some data. */
+ mostek_write(regs + MOSTEK_EEPROM, ~data1); /* Write back the complement. */
+ data2 = mostek_read(regs + MOSTEK_EEPROM); /* Read back the complement. */
+ mostek_write(regs + MOSTEK_EEPROM, data1); /* Restore original value. */
+
+ spin_unlock_irq(&mostek_lock);
+
+ return (data1 == data2); /* Was the write blocked? */
+}
+
+/* Probe for the real time clock chip. */
+static void __init set_system_time(void)
+{
+ unsigned int year, mon, day, hour, min, sec;
+ unsigned long mregs = mstk48t02_regs;
+#ifdef CONFIG_PCI
+ unsigned long dregs = ds1287_regs;
+#else
+ unsigned long dregs = 0UL;
+#endif
+ u8 tmp;
+
+ if (!mregs && !dregs) {
+ prom_printf("Something wrong, clock regs not mapped yet.\n");
+ prom_halt();
+ }
+
+ if (mregs) {
+ spin_lock_irq(&mostek_lock);
+
+ /* Traditional Mostek chip. */
+ tmp = mostek_read(mregs + MOSTEK_CREG);
+ tmp |= MSTK_CREG_READ;
+ mostek_write(mregs + MOSTEK_CREG, tmp);
+
+ 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) );
+ } else {
+ int i;
+
+ /* Dallas 12887 RTC chip. */
+
+ /* Stolen from arch/i386/kernel/time.c, see there for
+ * credits and descriptive comments.
+ */
+ for (i = 0; i < 1000000; i++) {
+ if (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP)
+ break;
+ udelay(10);
+ }
+ for (i = 0; i < 1000000; i++) {
+ if (!(CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP))
+ break;
+ udelay(10);
+ }
+ do {
+ sec = CMOS_READ(RTC_SECONDS);
+ min = CMOS_READ(RTC_MINUTES);
+ hour = CMOS_READ(RTC_HOURS);
+ day = CMOS_READ(RTC_DAY_OF_MONTH);
+ mon = CMOS_READ(RTC_MONTH);
+ year = CMOS_READ(RTC_YEAR);
+ } while (sec != CMOS_READ(RTC_SECONDS));
+ if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
+ BCD_TO_BIN(sec);
+ BCD_TO_BIN(min);
+ BCD_TO_BIN(hour);
+ BCD_TO_BIN(day);
+ BCD_TO_BIN(mon);
+ BCD_TO_BIN(year);
+ }
+ if ((year += 1900) < 1970)
+ year += 100;
+ }
+
+ 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);
+
+ if (mregs) {
+ tmp = mostek_read(mregs + MOSTEK_CREG);
+ tmp &= ~MSTK_CREG_READ;
+ mostek_write(mregs + MOSTEK_CREG, tmp);
+
+ spin_unlock_irq(&mostek_lock);
+ }
+}
+
+void __init clock_probe(void)
+{
+ struct linux_prom_registers clk_reg[2];
+ char model[128];
+ int node, busnd = -1, err;
+ unsigned long flags;
+ struct linux_central *cbus;
+#ifdef CONFIG_PCI
+ struct linux_ebus *ebus = NULL;
+ struct sparc_isa_bridge *isa_br = NULL;
+#endif
+ static int invoked;
+
+ if (invoked)
+ return;
+ invoked = 1;
+
+
+ if (this_is_starfire) {
+ /* davem suggests we keep this within the 4M locked kernel image */
+ static char obp_gettod[256];
+ static u32 unix_tod;
+
+ sprintf(obp_gettod, "h# %08x unix-gettod",
+ (unsigned int) (long) &unix_tod);
+ prom_feval(obp_gettod);
+ xtime.tv_sec = unix_tod;
+ xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
+ set_normalized_timespec(&wall_to_monotonic,
+ -xtime.tv_sec, -xtime.tv_nsec);
+ return;
+ }
+
+ local_irq_save(flags);
+
+ cbus = central_bus;
+ if (cbus != NULL)
+ busnd = central_bus->child->prom_node;
+
+ /* Check FHC Central then EBUSs then ISA bridges then SBUSs.
+ * That way we handle the presence of multiple properly.
+ *
+ * As a special case, machines with Central must provide the
+ * timer chip there.
+ */
+#ifdef CONFIG_PCI
+ if (ebus_chain != NULL) {
+ ebus = ebus_chain;
+ if (busnd == -1)
+ busnd = ebus->prom_node;
+ }
+ if (isa_chain != NULL) {
+ isa_br = isa_chain;
+ if (busnd == -1)
+ busnd = isa_br->prom_node;
+ }
+#endif
+ if (sbus_root != NULL && busnd == -1)
+ busnd = sbus_root->prom_node;
+
+ if (busnd == -1) {
+ prom_printf("clock_probe: problem, cannot find bus to search.\n");
+ prom_halt();
+ }
+
+ node = prom_getchild(busnd);
+
+ while (1) {
+ if (!node)
+ model[0] = 0;
+ else
+ prom_getstring(node, "model", model, sizeof(model));
+ if (strcmp(model, "mk48t02") &&
+ strcmp(model, "mk48t08") &&
+ strcmp(model, "mk48t59") &&
+ strcmp(model, "m5819") &&
+ strcmp(model, "m5819p") &&
+ strcmp(model, "m5823") &&
+ strcmp(model, "ds1287")) {
+ if (cbus != NULL) {
+ prom_printf("clock_probe: Central bus lacks timer chip.\n");
+ prom_halt();
+ }
+
+ if (node != 0)
+ node = prom_getsibling(node);
+#ifdef CONFIG_PCI
+ while ((node == 0) && ebus != NULL) {
+ ebus = ebus->next;
+ if (ebus != NULL) {
+ busnd = ebus->prom_node;
+ node = prom_getchild(busnd);
+ }
+ }
+ while ((node == 0) && isa_br != NULL) {
+ isa_br = isa_br->next;
+ if (isa_br != NULL) {
+ busnd = isa_br->prom_node;
+ node = prom_getchild(busnd);
+ }
+ }
+#endif
+ if (node == 0) {
+ prom_printf("clock_probe: Cannot find timer chip\n");
+ prom_halt();
+ }
+ continue;
+ }
+
+ err = prom_getproperty(node, "reg", (char *)clk_reg,
+ sizeof(clk_reg));
+ if(err == -1) {
+ prom_printf("clock_probe: Cannot get Mostek reg property\n");
+ prom_halt();
+ }
+
+ if (cbus != NULL) {
+ apply_fhc_ranges(central_bus->child, clk_reg, 1);
+ apply_central_ranges(central_bus, clk_reg, 1);
+ }
+#ifdef CONFIG_PCI
+ else if (ebus != NULL) {
+ struct linux_ebus_device *edev;
+
+ for_each_ebusdev(edev, ebus)
+ if (edev->prom_node == node)
+ break;
+ if (edev == NULL) {
+ if (isa_chain != NULL)
+ goto try_isa_clock;
+ prom_printf("%s: Mostek not probed by EBUS\n",
+ __FUNCTION__);
+ prom_halt();
+ }
+
+ if (!strcmp(model, "ds1287") ||
+ !strcmp(model, "m5819") ||
+ !strcmp(model, "m5819p") ||
+ !strcmp(model, "m5823")) {
+ ds1287_regs = edev->resource[0].start;
+ } else {
+ mstk48t59_regs = edev->resource[0].start;
+ mstk48t02_regs = mstk48t59_regs + MOSTEK_48T59_48T02;
+ }
+ break;
+ }
+ else if (isa_br != NULL) {
+ struct sparc_isa_device *isadev;
+
+try_isa_clock:
+ for_each_isadev(isadev, isa_br)
+ if (isadev->prom_node == node)
+ break;
+ if (isadev == NULL) {
+ prom_printf("%s: Mostek not probed by ISA\n");
+ prom_halt();
+ }
+ if (!strcmp(model, "ds1287") ||
+ !strcmp(model, "m5819") ||
+ !strcmp(model, "m5819p") ||
+ !strcmp(model, "m5823")) {
+ ds1287_regs = isadev->resource.start;
+ } else {
+ mstk48t59_regs = isadev->resource.start;
+ mstk48t02_regs = mstk48t59_regs + MOSTEK_48T59_48T02;
+ }
+ break;
+ }
+#endif
+ else {
+ if (sbus_root->num_sbus_ranges) {
+ int nranges = sbus_root->num_sbus_ranges;
+ int rngc;
+
+ for (rngc = 0; rngc < nranges; rngc++)
+ if (clk_reg[0].which_io ==
+ sbus_root->sbus_ranges[rngc].ot_child_space)
+ break;
+ if (rngc == nranges) {
+ prom_printf("clock_probe: Cannot find ranges for "
+ "clock regs.\n");
+ prom_halt();
+ }
+ clk_reg[0].which_io =
+ sbus_root->sbus_ranges[rngc].ot_parent_space;
+ clk_reg[0].phys_addr +=
+ sbus_root->sbus_ranges[rngc].ot_parent_base;
+ }
+ }
+
+ if(model[5] == '0' && model[6] == '2') {
+ mstk48t02_regs = (((u64)clk_reg[0].phys_addr) |
+ (((u64)clk_reg[0].which_io)<<32UL));
+ } else if(model[5] == '0' && model[6] == '8') {
+ mstk48t08_regs = (((u64)clk_reg[0].phys_addr) |
+ (((u64)clk_reg[0].which_io)<<32UL));
+ mstk48t02_regs = mstk48t08_regs + MOSTEK_48T08_48T02;
+ } else {
+ mstk48t59_regs = (((u64)clk_reg[0].phys_addr) |
+ (((u64)clk_reg[0].which_io)<<32UL));
+ mstk48t02_regs = mstk48t59_regs + MOSTEK_48T59_48T02;
+ }
+ break;
+ }
+
+ if (mstk48t02_regs != 0UL) {
+ /* Report a low battery voltage condition. */
+ if (has_low_battery())
+ prom_printf("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();
+ }
+
+ set_system_time();
+
+ local_irq_restore(flags);
+}
+
+/* This is gets the master TICK_INT timer going. */
+static unsigned long sparc64_init_timers(void)
+{
+ unsigned long clock;
+ int node;
+#ifdef CONFIG_SMP
+ extern void smp_tick_init(void);
+#endif
+
+ if (tlb_type == spitfire) {
+ unsigned long ver, manuf, impl;
+
+ __asm__ __volatile__ ("rdpr %%ver, %0"
+ : "=&r" (ver));
+ manuf = ((ver >> 48) & 0xffff);
+ impl = ((ver >> 32) & 0xffff);
+ if (manuf == 0x17 && impl == 0x13) {
+ /* Hummingbird, aka Ultra-IIe */
+ tick_ops = &hbtick_operations;
+ node = prom_root_node;
+ clock = prom_getint(node, "stick-frequency");
+ } else {
+ tick_ops = &tick_operations;
+ cpu_find_by_instance(0, &node, NULL);
+ clock = prom_getint(node, "clock-frequency");
+ }
+ } else {
+ tick_ops = &stick_operations;
+ node = prom_root_node;
+ clock = prom_getint(node, "stick-frequency");
+ }
+ timer_tick_offset = clock / HZ;
+
+#ifdef CONFIG_SMP
+ smp_tick_init();
+#endif
+
+ return clock;
+}
+
+static void sparc64_start_timers(irqreturn_t (*cfunc)(int, void *, struct pt_regs *))
+{
+ unsigned long pstate;
+ int err;
+
+ /* Register IRQ handler. */
+ err = request_irq(build_irq(0, 0, 0UL, 0UL), cfunc, SA_STATIC_ALLOC,
+ "timer", NULL);
+
+ if (err) {
+ prom_printf("Serious problem, cannot register TICK_INT\n");
+ prom_halt();
+ }
+
+ /* Guarantee that the following sequences execute
+ * uninterrupted.
+ */
+ __asm__ __volatile__("rdpr %%pstate, %0\n\t"
+ "wrpr %0, %1, %%pstate"
+ : "=r" (pstate)
+ : "i" (PSTATE_IE));
+
+ tick_ops->init_tick(timer_tick_offset);
+
+ /* Restore PSTATE_IE. */
+ __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
+ : /* no outputs */
+ : "r" (pstate));
+
+ local_irq_enable();
+}
+
+struct freq_table {
+ unsigned long udelay_val_ref;
+ unsigned long clock_tick_ref;
+ unsigned int ref_freq;
+};
+static DEFINE_PER_CPU(struct freq_table, sparc64_freq_table) = { 0, 0, 0 };
+
+unsigned long sparc64_get_clock_tick(unsigned int cpu)
+{
+ struct freq_table *ft = &per_cpu(sparc64_freq_table, cpu);
+
+ if (ft->clock_tick_ref)
+ return ft->clock_tick_ref;
+ return cpu_data(cpu).clock_tick;
+}
+
+#ifdef CONFIG_CPU_FREQ
+
+static int sparc64_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
+ void *data)
+{
+ struct cpufreq_freqs *freq = data;
+ unsigned int cpu = freq->cpu;
+ struct freq_table *ft = &per_cpu(sparc64_freq_table, cpu);
+
+ if (!ft->ref_freq) {
+ ft->ref_freq = freq->old;
+ ft->udelay_val_ref = cpu_data(cpu).udelay_val;
+ ft->clock_tick_ref = cpu_data(cpu).clock_tick;
+ }
+ if ((val == CPUFREQ_PRECHANGE && freq->old < freq->new) ||
+ (val == CPUFREQ_POSTCHANGE && freq->old > freq->new) ||
+ (val == CPUFREQ_RESUMECHANGE)) {
+ cpu_data(cpu).udelay_val =
+ cpufreq_scale(ft->udelay_val_ref,
+ ft->ref_freq,
+ freq->new);
+ cpu_data(cpu).clock_tick =
+ cpufreq_scale(ft->clock_tick_ref,
+ ft->ref_freq,
+ freq->new);
+ }
+
+ return 0;
+}
+
+static struct notifier_block sparc64_cpufreq_notifier_block = {
+ .notifier_call = sparc64_cpufreq_notifier
+};
+
+#endif /* CONFIG_CPU_FREQ */
+
+static struct time_interpolator sparc64_cpu_interpolator = {
+ .source = TIME_SOURCE_CPU,
+ .shift = 16,
+ .mask = 0xffffffffffffffffLL
+};
+
+/* The quotient formula is taken from the IA64 port. */
+#define SPARC64_NSEC_PER_CYC_SHIFT 30UL
+void __init time_init(void)
+{
+ unsigned long clock = sparc64_init_timers();
+
+ sparc64_cpu_interpolator.frequency = clock;
+ register_time_interpolator(&sparc64_cpu_interpolator);
+
+ /* Now that the interpolator is registered, it is
+ * safe to start the timer ticking.
+ */
+ sparc64_start_timers(timer_interrupt);
+
+ timer_ticks_per_nsec_quotient =
+ (((NSEC_PER_SEC << SPARC64_NSEC_PER_CYC_SHIFT) +
+ (clock / 2)) / clock);
+
+#ifdef CONFIG_CPU_FREQ
+ cpufreq_register_notifier(&sparc64_cpufreq_notifier_block,
+ CPUFREQ_TRANSITION_NOTIFIER);
+#endif
+}
+
+unsigned long long sched_clock(void)
+{
+ unsigned long ticks = tick_ops->get_tick();
+
+ return (ticks * timer_ticks_per_nsec_quotient)
+ >> SPARC64_NSEC_PER_CYC_SHIFT;
+}
+
+static int set_rtc_mmss(unsigned long nowtime)
+{
+ int real_seconds, real_minutes, chip_minutes;
+ unsigned long mregs = mstk48t02_regs;
+#ifdef CONFIG_PCI
+ unsigned long dregs = ds1287_regs;
+#else
+ unsigned long dregs = 0UL;
+#endif
+ unsigned long flags;
+ u8 tmp;
+
+ /*
+ * Not having a register set can lead to trouble.
+ * Also starfire doesn't have a tod clock.
+ */
+ if (!mregs && !dregs)
+ return -1;
+
+ if (mregs) {
+ spin_lock_irqsave(&mostek_lock, flags);
+
+ /* Read the current RTC minutes. */
+ tmp = mostek_read(mregs + MOSTEK_CREG);
+ tmp |= MSTK_CREG_READ;
+ mostek_write(mregs + MOSTEK_CREG, tmp);
+
+ chip_minutes = MSTK_REG_MIN(mregs);
+
+ tmp = mostek_read(mregs + MOSTEK_CREG);
+ tmp &= ~MSTK_CREG_READ;
+ mostek_write(mregs + MOSTEK_CREG, tmp);
+
+ /*
+ * 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 - chip_minutes) + 15)/30) & 1)
+ real_minutes += 30; /* correct for half hour time zone */
+ real_minutes %= 60;
+
+ if (abs(real_minutes - chip_minutes) < 30) {
+ tmp = mostek_read(mregs + MOSTEK_CREG);
+ tmp |= MSTK_CREG_WRITE;
+ mostek_write(mregs + MOSTEK_CREG, tmp);
+
+ MSTK_SET_REG_SEC(mregs,real_seconds);
+ MSTK_SET_REG_MIN(mregs,real_minutes);
+
+ tmp = mostek_read(mregs + MOSTEK_CREG);
+ tmp &= ~MSTK_CREG_WRITE;
+ mostek_write(mregs + MOSTEK_CREG, tmp);
+
+ spin_unlock_irqrestore(&mostek_lock, flags);
+
+ return 0;
+ } else {
+ spin_unlock_irqrestore(&mostek_lock, flags);
+
+ return -1;
+ }
+ } else {
+ int retval = 0;
+ unsigned char save_control, save_freq_select;
+
+ /* Stolen from arch/i386/kernel/time.c, see there for
+ * credits and descriptive comments.
+ */
+ spin_lock_irqsave(&rtc_lock, flags);
+ save_control = CMOS_READ(RTC_CONTROL); /* tell the clock it's being set */
+ CMOS_WRITE((save_control|RTC_SET), RTC_CONTROL);
+
+ save_freq_select = CMOS_READ(RTC_FREQ_SELECT); /* stop and reset prescaler */
+ CMOS_WRITE((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT);
+
+ chip_minutes = CMOS_READ(RTC_MINUTES);
+ if (!(save_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
+ BCD_TO_BIN(chip_minutes);
+ real_seconds = nowtime % 60;
+ real_minutes = nowtime / 60;
+ if (((abs(real_minutes - chip_minutes) + 15)/30) & 1)
+ real_minutes += 30;
+ real_minutes %= 60;
+
+ if (abs(real_minutes - chip_minutes) < 30) {
+ if (!(save_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
+ BIN_TO_BCD(real_seconds);
+ BIN_TO_BCD(real_minutes);
+ }
+ CMOS_WRITE(real_seconds,RTC_SECONDS);
+ CMOS_WRITE(real_minutes,RTC_MINUTES);
+ } else {
+ printk(KERN_WARNING
+ "set_rtc_mmss: can't update from %d to %d\n",
+ chip_minutes, real_minutes);
+ retval = -1;
+ }
+
+ CMOS_WRITE(save_control, RTC_CONTROL);
+ CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT);
+ spin_unlock_irqrestore(&rtc_lock, flags);
+
+ return retval;
+ }
+}