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-rw-r--r--arch/sh/kernel/time_64.c519
1 files changed, 519 insertions, 0 deletions
diff --git a/arch/sh/kernel/time_64.c b/arch/sh/kernel/time_64.c
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+++ b/arch/sh/kernel/time_64.c
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+/*
+ * arch/sh/kernel/time_64.c
+ *
+ * Copyright (C) 2000, 2001 Paolo Alberelli
+ * Copyright (C) 2003 - 2007 Paul Mundt
+ * Copyright (C) 2003 Richard Curnow
+ *
+ * Original TMU/RTC code taken from sh version.
+ * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka
+ * Some code taken from i386 version.
+ * Copyright (C) 1991, 1992, 1995 Linus Torvalds
+ *
+ * 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/errno.h>
+#include <linux/rwsem.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/delay.h>
+#include <linux/init.h>
+#include <linux/profile.h>
+#include <linux/smp.h>
+#include <linux/module.h>
+#include <linux/bcd.h>
+#include <linux/timex.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <asm/cpu/registers.h> /* required by inline __asm__ stmt. */
+#include <asm/cpu/irq.h>
+#include <asm/addrspace.h>
+#include <asm/processor.h>
+#include <asm/uaccess.h>
+#include <asm/delay.h>
+
+#define TMU_TOCR_INIT 0x00
+#define TMU0_TCR_INIT 0x0020
+#define TMU_TSTR_INIT 1
+#define TMU_TSTR_OFF 0
+
+/* Real Time Clock */
+#define RTC_BLOCK_OFF 0x01040000
+#define RTC_BASE PHYS_PERIPHERAL_BLOCK + RTC_BLOCK_OFF
+#define RTC_RCR1_CIE 0x10 /* Carry Interrupt Enable */
+#define RTC_RCR1 (rtc_base + 0x38)
+
+/* Clock, Power and Reset Controller */
+#define CPRC_BLOCK_OFF 0x01010000
+#define CPRC_BASE PHYS_PERIPHERAL_BLOCK + CPRC_BLOCK_OFF
+
+#define FRQCR (cprc_base+0x0)
+#define WTCSR (cprc_base+0x0018)
+#define STBCR (cprc_base+0x0030)
+
+/* Time Management Unit */
+#define TMU_BLOCK_OFF 0x01020000
+#define TMU_BASE PHYS_PERIPHERAL_BLOCK + TMU_BLOCK_OFF
+#define TMU0_BASE tmu_base + 0x8 + (0xc * 0x0)
+#define TMU1_BASE tmu_base + 0x8 + (0xc * 0x1)
+#define TMU2_BASE tmu_base + 0x8 + (0xc * 0x2)
+
+#define TMU_TOCR tmu_base+0x0 /* Byte access */
+#define TMU_TSTR tmu_base+0x4 /* Byte access */
+
+#define TMU0_TCOR TMU0_BASE+0x0 /* Long access */
+#define TMU0_TCNT TMU0_BASE+0x4 /* Long access */
+#define TMU0_TCR TMU0_BASE+0x8 /* Word access */
+
+#define TICK_SIZE (tick_nsec / 1000)
+
+static unsigned long tmu_base, rtc_base;
+unsigned long cprc_base;
+
+/* Variables to allow interpolation of time of day to resolution better than a
+ * jiffy. */
+
+/* This is effectively protected by xtime_lock */
+static unsigned long ctc_last_interrupt;
+static unsigned long long usecs_per_jiffy = 1000000/HZ; /* Approximation */
+
+#define CTC_JIFFY_SCALE_SHIFT 40
+
+/* 2**CTC_JIFFY_SCALE_SHIFT / ctc_ticks_per_jiffy */
+static unsigned long long scaled_recip_ctc_ticks_per_jiffy;
+
+/* Estimate number of microseconds that have elapsed since the last timer tick,
+ by scaling the delta that has occurred in the CTC register.
+
+ WARNING WARNING WARNING : This algorithm relies on the CTC decrementing at
+ the CPU clock rate. If the CPU sleeps, the CTC stops counting. Bear this
+ in mind if enabling SLEEP_WORKS in process.c. In that case, this algorithm
+ probably needs to use TMU.TCNT0 instead. This will work even if the CPU is
+ sleeping, though will be coarser.
+
+ FIXME : What if usecs_per_tick is moving around too much, e.g. if an adjtime
+ is running or if the freq or tick arguments of adjtimex are modified after
+ we have calibrated the scaling factor? This will result in either a jump at
+ the end of a tick period, or a wrap backwards at the start of the next one,
+ if the application is reading the time of day often enough. I think we
+ ought to do better than this. For this reason, usecs_per_jiffy is left
+ separated out in the calculation below. This allows some future hook into
+ the adjtime-related stuff in kernel/timer.c to remove this hazard.
+
+*/
+
+static unsigned long usecs_since_tick(void)
+{
+ unsigned long long current_ctc;
+ long ctc_ticks_since_interrupt;
+ unsigned long long ull_ctc_ticks_since_interrupt;
+ unsigned long result;
+
+ unsigned long long mul1_out;
+ unsigned long long mul1_out_high;
+ unsigned long long mul2_out_low, mul2_out_high;
+
+ /* Read CTC register */
+ asm ("getcon cr62, %0" : "=r" (current_ctc));
+ /* Note, the CTC counts down on each CPU clock, not up.
+ Note(2), use long type to get correct wraparound arithmetic when
+ the counter crosses zero. */
+ ctc_ticks_since_interrupt = (long) ctc_last_interrupt - (long) current_ctc;
+ ull_ctc_ticks_since_interrupt = (unsigned long long) ctc_ticks_since_interrupt;
+
+ /* Inline assembly to do 32x32x32->64 multiplier */
+ asm volatile ("mulu.l %1, %2, %0" :
+ "=r" (mul1_out) :
+ "r" (ull_ctc_ticks_since_interrupt), "r" (usecs_per_jiffy));
+
+ mul1_out_high = mul1_out >> 32;
+
+ asm volatile ("mulu.l %1, %2, %0" :
+ "=r" (mul2_out_low) :
+ "r" (mul1_out), "r" (scaled_recip_ctc_ticks_per_jiffy));
+
+#if 1
+ asm volatile ("mulu.l %1, %2, %0" :
+ "=r" (mul2_out_high) :
+ "r" (mul1_out_high), "r" (scaled_recip_ctc_ticks_per_jiffy));
+#endif
+
+ result = (unsigned long) (((mul2_out_high << 32) + mul2_out_low) >> CTC_JIFFY_SCALE_SHIFT);
+
+ return result;
+}
+
+void do_gettimeofday(struct timeval *tv)
+{
+ unsigned long flags;
+ unsigned long seq;
+ unsigned long usec, sec;
+
+ do {
+ seq = read_seqbegin_irqsave(&xtime_lock, flags);
+ usec = usecs_since_tick();
+ 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;
+}
+
+int 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;
+
+ write_seqlock_irq(&xtime_lock);
+ /*
+ * 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 * usecs_since_tick();
+
+ 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);
+
+ ntp_clear();
+ write_sequnlock_irq(&xtime_lock);
+ clock_was_set();
+
+ return 0;
+}
+EXPORT_SYMBOL(do_settimeofday);
+
+/* Dummy RTC ops */
+static void null_rtc_get_time(struct timespec *tv)
+{
+ tv->tv_sec = mktime(2000, 1, 1, 0, 0, 0);
+ tv->tv_nsec = 0;
+}
+
+static int null_rtc_set_time(const time_t secs)
+{
+ return 0;
+}
+
+void (*rtc_sh_get_time)(struct timespec *) = null_rtc_get_time;
+int (*rtc_sh_set_time)(const time_t) = null_rtc_set_time;
+
+/* last time the RTC clock got updated */
+static long last_rtc_update;
+
+/*
+ * timer_interrupt() needs to keep up the real-time clock,
+ * as well as call the "do_timer()" routine every clocktick
+ */
+static inline void do_timer_interrupt(void)
+{
+ unsigned long long current_ctc;
+ asm ("getcon cr62, %0" : "=r" (current_ctc));
+ ctc_last_interrupt = (unsigned long) current_ctc;
+
+ do_timer(1);
+#ifndef CONFIG_SMP
+ update_process_times(user_mode(get_irq_regs()));
+#endif
+ if (current->pid)
+ profile_tick(CPU_PROFILING);
+
+#ifdef CONFIG_HEARTBEAT
+ if (sh_mv.mv_heartbeat != NULL)
+ sh_mv.mv_heartbeat();
+#endif
+
+ /*
+ * If we have an externally synchronized Linux clock, then update
+ * RTC clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
+ * called as close as possible to 500 ms before the new second starts.
+ */
+ if (ntp_synced() &&
+ 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 (rtc_sh_set_time(xtime.tv_sec) == 0)
+ last_rtc_update = xtime.tv_sec;
+ else
+ /* do it again in 60 s */
+ last_rtc_update = xtime.tv_sec - 600;
+ }
+}
+
+/*
+ * This is the same as the above, except we _also_ save the current
+ * Time Stamp Counter value at the time of the timer interrupt, so that
+ * we later on can estimate the time of day more exactly.
+ */
+static irqreturn_t timer_interrupt(int irq, void *dev_id)
+{
+ unsigned long timer_status;
+
+ /* Clear UNF bit */
+ timer_status = ctrl_inw(TMU0_TCR);
+ timer_status &= ~0x100;
+ ctrl_outw(timer_status, TMU0_TCR);
+
+ /*
+ * Here we are in the timer irq handler. We just have irqs locally
+ * disabled but we don't know if the timer_bh is running on the other
+ * CPU. We need to avoid to SMP race with it. NOTE: we don' t need
+ * the irq version of write_lock because as just said we have irq
+ * locally disabled. -arca
+ */
+ write_lock(&xtime_lock);
+ do_timer_interrupt();
+ write_unlock(&xtime_lock);
+
+ return IRQ_HANDLED;
+}
+
+
+static __init unsigned int get_cpu_hz(void)
+{
+ unsigned int count;
+ unsigned long __dummy;
+ unsigned long ctc_val_init, ctc_val;
+
+ /*
+ ** Regardless the toolchain, force the compiler to use the
+ ** arbitrary register r3 as a clock tick counter.
+ ** NOTE: r3 must be in accordance with sh64_rtc_interrupt()
+ */
+ register unsigned long long __rtc_irq_flag __asm__ ("r3");
+
+ local_irq_enable();
+ do {} while (ctrl_inb(rtc_base) != 0);
+ ctrl_outb(RTC_RCR1_CIE, RTC_RCR1); /* Enable carry interrupt */
+
+ /*
+ * r3 is arbitrary. CDC does not support "=z".
+ */
+ ctc_val_init = 0xffffffff;
+ ctc_val = ctc_val_init;
+
+ asm volatile("gettr tr0, %1\n\t"
+ "putcon %0, " __CTC "\n\t"
+ "and %2, r63, %2\n\t"
+ "pta $+4, tr0\n\t"
+ "beq/l %2, r63, tr0\n\t"
+ "ptabs %1, tr0\n\t"
+ "getcon " __CTC ", %0\n\t"
+ : "=r"(ctc_val), "=r" (__dummy), "=r" (__rtc_irq_flag)
+ : "0" (0));
+ local_irq_disable();
+ /*
+ * SH-3:
+ * CPU clock = 4 stages * loop
+ * tst rm,rm if id ex
+ * bt/s 1b if id ex
+ * add #1,rd if id ex
+ * (if) pipe line stole
+ * tst rm,rm if id ex
+ * ....
+ *
+ *
+ * SH-4:
+ * CPU clock = 6 stages * loop
+ * I don't know why.
+ * ....
+ *
+ * SH-5:
+ * Use CTC register to count. This approach returns the right value
+ * even if the I-cache is disabled (e.g. whilst debugging.)
+ *
+ */
+
+ count = ctc_val_init - ctc_val; /* CTC counts down */
+
+ /*
+ * This really is count by the number of clock cycles
+ * by the ratio between a complete R64CNT
+ * wrap-around (128) and CUI interrupt being raised (64).
+ */
+ return count*2;
+}
+
+static irqreturn_t sh64_rtc_interrupt(int irq, void *dev_id)
+{
+ struct pt_regs *regs = get_irq_regs();
+
+ ctrl_outb(0, RTC_RCR1); /* Disable Carry Interrupts */
+ regs->regs[3] = 1; /* Using r3 */
+
+ return IRQ_HANDLED;
+}
+
+static struct irqaction irq0 = {
+ .handler = timer_interrupt,
+ .flags = IRQF_DISABLED,
+ .mask = CPU_MASK_NONE,
+ .name = "timer",
+};
+static struct irqaction irq1 = {
+ .handler = sh64_rtc_interrupt,
+ .flags = IRQF_DISABLED,
+ .mask = CPU_MASK_NONE,
+ .name = "rtc",
+};
+
+void __init time_init(void)
+{
+ unsigned int cpu_clock, master_clock, bus_clock, module_clock;
+ unsigned long interval;
+ unsigned long frqcr, ifc, pfc;
+ static int ifc_table[] = { 2, 4, 6, 8, 10, 12, 16, 24 };
+#define bfc_table ifc_table /* Same */
+#define pfc_table ifc_table /* Same */
+
+ tmu_base = onchip_remap(TMU_BASE, 1024, "TMU");
+ if (!tmu_base) {
+ panic("Unable to remap TMU\n");
+ }
+
+ rtc_base = onchip_remap(RTC_BASE, 1024, "RTC");
+ if (!rtc_base) {
+ panic("Unable to remap RTC\n");
+ }
+
+ cprc_base = onchip_remap(CPRC_BASE, 1024, "CPRC");
+ if (!cprc_base) {
+ panic("Unable to remap CPRC\n");
+ }
+
+ rtc_sh_get_time(&xtime);
+
+ setup_irq(TIMER_IRQ, &irq0);
+ setup_irq(RTC_IRQ, &irq1);
+
+ /* Check how fast it is.. */
+ cpu_clock = get_cpu_hz();
+
+ /* Note careful order of operations to maintain reasonable precision and avoid overflow. */
+ scaled_recip_ctc_ticks_per_jiffy = ((1ULL << CTC_JIFFY_SCALE_SHIFT) / (unsigned long long)(cpu_clock / HZ));
+
+ free_irq(RTC_IRQ, NULL);
+
+ printk("CPU clock: %d.%02dMHz\n",
+ (cpu_clock / 1000000), (cpu_clock % 1000000)/10000);
+ {
+ unsigned short bfc;
+ frqcr = ctrl_inl(FRQCR);
+ ifc = ifc_table[(frqcr>> 6) & 0x0007];
+ bfc = bfc_table[(frqcr>> 3) & 0x0007];
+ pfc = pfc_table[(frqcr>> 12) & 0x0007];
+ master_clock = cpu_clock * ifc;
+ bus_clock = master_clock/bfc;
+ }
+
+ printk("Bus clock: %d.%02dMHz\n",
+ (bus_clock/1000000), (bus_clock % 1000000)/10000);
+ module_clock = master_clock/pfc;
+ printk("Module clock: %d.%02dMHz\n",
+ (module_clock/1000000), (module_clock % 1000000)/10000);
+ interval = (module_clock/(HZ*4));
+
+ printk("Interval = %ld\n", interval);
+
+ current_cpu_data.cpu_clock = cpu_clock;
+ current_cpu_data.master_clock = master_clock;
+ current_cpu_data.bus_clock = bus_clock;
+ current_cpu_data.module_clock = module_clock;
+
+ /* Start TMU0 */
+ ctrl_outb(TMU_TSTR_OFF, TMU_TSTR);
+ ctrl_outb(TMU_TOCR_INIT, TMU_TOCR);
+ ctrl_outw(TMU0_TCR_INIT, TMU0_TCR);
+ ctrl_outl(interval, TMU0_TCOR);
+ ctrl_outl(interval, TMU0_TCNT);
+ ctrl_outb(TMU_TSTR_INIT, TMU_TSTR);
+}
+
+void enter_deep_standby(void)
+{
+ /* Disable watchdog timer */
+ ctrl_outl(0xa5000000, WTCSR);
+ /* Configure deep standby on sleep */
+ ctrl_outl(0x03, STBCR);
+
+#ifdef CONFIG_SH_ALPHANUMERIC
+ {
+ extern void mach_alphanum(int position, unsigned char value);
+ extern void mach_alphanum_brightness(int setting);
+ char halted[] = "Halted. ";
+ int i;
+ mach_alphanum_brightness(6); /* dimmest setting above off */
+ for (i=0; i<8; i++) {
+ mach_alphanum(i, halted[i]);
+ }
+ asm __volatile__ ("synco");
+ }
+#endif
+
+ asm __volatile__ ("sleep");
+ asm __volatile__ ("synci");
+ asm __volatile__ ("nop");
+ asm __volatile__ ("nop");
+ asm __volatile__ ("nop");
+ asm __volatile__ ("nop");
+ panic("Unexpected wakeup!\n");
+}
+
+static struct resource rtc_resources[] = {
+ [0] = {
+ /* RTC base, filled in by rtc_init */
+ .flags = IORESOURCE_IO,
+ },
+ [1] = {
+ /* Period IRQ */
+ .start = IRQ_PRI,
+ .flags = IORESOURCE_IRQ,
+ },
+ [2] = {
+ /* Carry IRQ */
+ .start = IRQ_CUI,
+ .flags = IORESOURCE_IRQ,
+ },
+ [3] = {
+ /* Alarm IRQ */
+ .start = IRQ_ATI,
+ .flags = IORESOURCE_IRQ,
+ },
+};
+
+static struct platform_device rtc_device = {
+ .name = "sh-rtc",
+ .id = -1,
+ .num_resources = ARRAY_SIZE(rtc_resources),
+ .resource = rtc_resources,
+};
+
+static int __init rtc_init(void)
+{
+ rtc_resources[0].start = rtc_base;
+ rtc_resources[0].end = rtc_resources[0].start + 0x58 - 1;
+
+ return platform_device_register(&rtc_device);
+}
+device_initcall(rtc_init);
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