diff options
Diffstat (limited to 'arch/sh/kernel/timers/timer-tmu.c')
| -rw-r--r-- | arch/sh/kernel/timers/timer-tmu.c | 229 |
1 files changed, 0 insertions, 229 deletions
diff --git a/arch/sh/kernel/timers/timer-tmu.c b/arch/sh/kernel/timers/timer-tmu.c deleted file mode 100644 index 96a64cb1310..00000000000 --- a/arch/sh/kernel/timers/timer-tmu.c +++ /dev/null @@ -1,229 +0,0 @@ -/* - * arch/sh/kernel/timers/timer-tmu.c - TMU Timer Support - * - * Copyright (C) 2005 Paul Mundt - * - * TMU handling code hacked out of arch/sh/kernel/time.c - * - * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka - * Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org> - * Copyright (C) 2002, 2003, 2004 Paul Mundt - * Copyright (C) 2002 M. R. Brown <mrbrown@linux-sh.org> - * - * 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/init.h> -#include <linux/kernel.h> -#include <linux/interrupt.h> -#include <linux/spinlock.h> -#include <linux/seqlock.h> -#include <asm/timer.h> -#include <asm/rtc.h> -#include <asm/io.h> -#include <asm/irq.h> -#include <asm/clock.h> - -#define TMU_TOCR_INIT 0x00 -#define TMU0_TCR_INIT 0x0020 -#define TMU_TSTR_INIT 1 - -#define TMU0_TCR_CALIB 0x0000 - -static DEFINE_SPINLOCK(tmu0_lock); - -static unsigned long tmu_timer_get_offset(void) -{ - int count; - unsigned long flags; - - static int count_p = 0x7fffffff; /* for the first call after boot */ - static unsigned long jiffies_p = 0; - - /* - * cache volatile jiffies temporarily; we have IRQs turned off. - */ - unsigned long jiffies_t; - - spin_lock_irqsave(&tmu0_lock, flags); - /* timer count may underflow right here */ - count = ctrl_inl(TMU0_TCNT); /* read the latched count */ - - jiffies_t = jiffies; - - /* - * avoiding timer inconsistencies (they are rare, but they happen)... - * there is one kind of problem that must be avoided here: - * 1. the timer counter underflows - */ - - if (jiffies_t == jiffies_p) { - if (count > count_p) { - /* the nutcase */ - if (ctrl_inw(TMU0_TCR) & 0x100) { /* Check UNF bit */ - count -= LATCH; - } else { - printk("%s (): hardware timer problem?\n", - __FUNCTION__); - } - } - } else - jiffies_p = jiffies_t; - - count_p = count; - spin_unlock_irqrestore(&tmu0_lock, flags); - - count = ((LATCH-1) - count) * TICK_SIZE; - count = (count + LATCH/2) / LATCH; - - return count; -} - -static irqreturn_t tmu_timer_interrupt(int irq, void *dev_id, - struct pt_regs *regs) -{ - 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_seqlock(&xtime_lock); - handle_timer_tick(regs); - write_sequnlock(&xtime_lock); - - return IRQ_HANDLED; -} - -static struct irqaction tmu_irq = { - .name = "timer", - .handler = tmu_timer_interrupt, - .flags = SA_INTERRUPT, - .mask = CPU_MASK_NONE, -}; - -/* - * Hah! We'll see if this works (switching from usecs to nsecs). - */ -static unsigned long tmu_timer_get_frequency(void) -{ - u32 freq; - struct timespec ts1, ts2; - unsigned long diff_nsec; - unsigned long factor; - - /* Setup the timer: We don't want to generate interrupts, just - * have it count down at its natural rate. - */ - ctrl_outb(0, TMU_TSTR); -#if !defined(CONFIG_CPU_SUBTYPE_SH7300) && !defined(CONFIG_CPU_SUBTYPE_SH7760) - ctrl_outb(TMU_TOCR_INIT, TMU_TOCR); -#endif - ctrl_outw(TMU0_TCR_CALIB, TMU0_TCR); - ctrl_outl(0xffffffff, TMU0_TCOR); - ctrl_outl(0xffffffff, TMU0_TCNT); - - rtc_get_time(&ts2); - - do { - rtc_get_time(&ts1); - } while (ts1.tv_nsec == ts2.tv_nsec && ts1.tv_sec == ts2.tv_sec); - - /* actually start the timer */ - ctrl_outb(TMU_TSTR_INIT, TMU_TSTR); - - do { - rtc_get_time(&ts2); - } while (ts1.tv_nsec == ts2.tv_nsec && ts1.tv_sec == ts2.tv_sec); - - freq = 0xffffffff - ctrl_inl(TMU0_TCNT); - if (ts2.tv_nsec < ts1.tv_nsec) { - ts2.tv_nsec += 1000000000; - ts2.tv_sec--; - } - - diff_nsec = (ts2.tv_sec - ts1.tv_sec) * 1000000000 + (ts2.tv_nsec - ts1.tv_nsec); - - /* this should work well if the RTC has a precision of n Hz, where - * n is an integer. I don't think we have to worry about the other - * cases. */ - factor = (1000000000 + diff_nsec/2) / diff_nsec; - - if (factor * diff_nsec > 1100000000 || - factor * diff_nsec < 900000000) - panic("weird RTC (diff_nsec %ld)", diff_nsec); - - return freq * factor; -} - -static void tmu_clk_init(struct clk *clk) -{ - u8 divisor = TMU0_TCR_INIT & 0x7; - ctrl_outw(TMU0_TCR_INIT, TMU0_TCR); - clk->rate = clk->parent->rate / (4 << (divisor << 1)); -} - -static void tmu_clk_recalc(struct clk *clk) -{ - u8 divisor = ctrl_inw(TMU0_TCR) & 0x7; - clk->rate = clk->parent->rate / (4 << (divisor << 1)); -} - -static struct clk_ops tmu_clk_ops = { - .init = tmu_clk_init, - .recalc = tmu_clk_recalc, -}; - -static struct clk tmu0_clk = { - .name = "tmu0_clk", - .ops = &tmu_clk_ops, -}; - -static int tmu_timer_init(void) -{ - unsigned long interval; - - setup_irq(TIMER_IRQ, &tmu_irq); - - tmu0_clk.parent = clk_get("module_clk"); - - /* Start TMU0 */ - ctrl_outb(0, TMU_TSTR); -#if !defined(CONFIG_CPU_SUBTYPE_SH7300) && !defined(CONFIG_CPU_SUBTYPE_SH7760) - ctrl_outb(TMU_TOCR_INIT, TMU_TOCR); -#endif - - clk_register(&tmu0_clk); - clk_enable(&tmu0_clk); - - interval = (clk_get_rate(&tmu0_clk) + HZ / 2) / HZ; - printk(KERN_INFO "Interval = %ld\n", interval); - - ctrl_outl(interval, TMU0_TCOR); - ctrl_outl(interval, TMU0_TCNT); - - ctrl_outb(TMU_TSTR_INIT, TMU_TSTR); - - return 0; -} - -struct sys_timer_ops tmu_timer_ops = { - .init = tmu_timer_init, - .get_frequency = tmu_timer_get_frequency, - .get_offset = tmu_timer_get_offset, -}; - -struct sys_timer tmu_timer = { - .name = "tmu", - .ops = &tmu_timer_ops, -}; - |
