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-rw-r--r--arch/v850/kernel/highres_timer.c132
1 files changed, 0 insertions, 132 deletions
diff --git a/arch/v850/kernel/highres_timer.c b/arch/v850/kernel/highres_timer.c
deleted file mode 100644
index b16ad1e..0000000
--- a/arch/v850/kernel/highres_timer.c
+++ /dev/null
@@ -1,132 +0,0 @@
-/*
- * arch/v850/kernel/highres_timer.c -- High resolution timing routines
- *
- * Copyright (C) 2001,02,03 NEC Electronics Corporation
- * Copyright (C) 2001,02,03 Miles Bader <miles@gnu.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.
- *
- * Written by Miles Bader <miles@gnu.org>
- */
-
-#include <asm/system.h>
-#include <asm/v850e_timer_d.h>
-#include <asm/highres_timer.h>
-
-#define HIGHRES_TIMER_USEC_SHIFT 12
-
-/* Pre-calculated constant used for converting ticks to real time
- units. We initialize it to prevent it being put into BSS. */
-static u32 highres_timer_usec_prescale = 1;
-
-void highres_timer_slow_tick_irq (void) __attribute__ ((noreturn));
-void highres_timer_slow_tick_irq (void)
-{
- /* This is an interrupt handler, so it must be very careful to
- not to trash any registers. At this point, the stack-pointer
- (r3) has been saved in the chip ram location ENTRY_SP by the
- interrupt vector, so we can use it as a scratch register; we
- must also restore it before returning. */
- asm ("ld.w %0[r0], sp;"
- "add 1, sp;"
- "st.w sp, %0[r0];"
- "ld.w %1[r0], sp;" /* restore pre-irq stack-pointer */
- "reti"
- ::
- "i" (HIGHRES_TIMER_SLOW_TICKS_ADDR),
- "i" (ENTRY_SP_ADDR)
- : "memory");
-}
-
-void highres_timer_reset (void)
-{
- V850E_TIMER_D_TMD (HIGHRES_TIMER_TIMER_D_UNIT) = 0;
- HIGHRES_TIMER_SLOW_TICKS = 0;
-}
-
-void highres_timer_start (void)
-{
- u32 fast_tick_rate;
-
- /* Start hardware timer. */
- v850e_timer_d_configure (HIGHRES_TIMER_TIMER_D_UNIT,
- HIGHRES_TIMER_SLOW_TICK_RATE);
-
- fast_tick_rate =
- (V850E_TIMER_D_BASE_FREQ
- >> V850E_TIMER_D_DIVLOG2 (HIGHRES_TIMER_TIMER_D_UNIT));
-
- /* The obvious way of calculating microseconds from fast ticks
- is to do:
-
- usec = fast_ticks * 10^6 / fast_tick_rate
-
- However, divisions are much slower than multiplications, and
- the above calculation can overflow, so we do this instead:
-
- usec = fast_ticks * (10^6 * 2^12 / fast_tick_rate) / 2^12
-
- since we can pre-calculate (10^6 * (2^12 / fast_tick_rate))
- and use a shift for dividing by 2^12, this avoids division,
- and is almost as accurate (it differs by about 2 microseconds
- at the extreme value of the fast-tick counter's ranger). */
- highres_timer_usec_prescale = ((1000000 << HIGHRES_TIMER_USEC_SHIFT)
- / fast_tick_rate);
-
- /* Enable the interrupt (which is hardwired to this use), and
- give it the highest priority. */
- V850E_INTC_IC (IRQ_INTCMD (HIGHRES_TIMER_TIMER_D_UNIT)) = 0;
-}
-
-void highres_timer_stop (void)
-{
- /* Stop the timer. */
- V850E_TIMER_D_TMCD (HIGHRES_TIMER_TIMER_D_UNIT) =
- V850E_TIMER_D_TMCD_CAE;
- /* Disable its interrupt, just in case. */
- v850e_intc_disable_irq (IRQ_INTCMD (HIGHRES_TIMER_TIMER_D_UNIT));
-}
-
-inline void highres_timer_read_ticks (u32 *slow_ticks, u32 *fast_ticks)
-{
- int flags;
- u32 fast_ticks_1, fast_ticks_2, _slow_ticks;
-
- local_irq_save (flags);
- fast_ticks_1 = V850E_TIMER_D_TMD (HIGHRES_TIMER_TIMER_D_UNIT);
- _slow_ticks = HIGHRES_TIMER_SLOW_TICKS;
- fast_ticks_2 = V850E_TIMER_D_TMD (HIGHRES_TIMER_TIMER_D_UNIT);
- local_irq_restore (flags);
-
- if (fast_ticks_2 < fast_ticks_1)
- _slow_ticks++;
-
- *slow_ticks = _slow_ticks;
- *fast_ticks = fast_ticks_2;
-}
-
-inline void highres_timer_ticks_to_timeval (u32 slow_ticks, u32 fast_ticks,
- struct timeval *tv)
-{
- unsigned long sec, sec_rem, usec;
-
- usec = ((fast_ticks * highres_timer_usec_prescale)
- >> HIGHRES_TIMER_USEC_SHIFT);
-
- sec = slow_ticks / HIGHRES_TIMER_SLOW_TICK_RATE;
- sec_rem = slow_ticks % HIGHRES_TIMER_SLOW_TICK_RATE;
-
- usec += sec_rem * (1000000 / HIGHRES_TIMER_SLOW_TICK_RATE);
-
- tv->tv_sec = sec;
- tv->tv_usec = usec;
-}
-
-void highres_timer_read (struct timeval *tv)
-{
- u32 fast_ticks, slow_ticks;
- highres_timer_read_ticks (&slow_ticks, &fast_ticks);
- highres_timer_ticks_to_timeval (slow_ticks, fast_ticks, tv);
-}
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