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/*
* include/asm-v850/v850e_utils.h -- Utility functions associated with
* V850E CPUs
*
* Copyright (C) 2001,03 NEC Electronics Corporation
* Copyright (C) 2001,03 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>
*/
#ifndef __V850_V850E_UTILS_H__
#define __V850_V850E_UTILS_H__
/* Calculate counter clock-divider and count values to attain the
desired frequency RATE from the base frequency BASE_FREQ. The
counter is expected to have a clock-divider, which can divide the
system cpu clock by a power of two value from MIN_DIVLOG2 to
MAX_DIV_LOG2, and a word-size of COUNTER_SIZE bits (the counter
counts up and resets whenever it's equal to the compare register,
generating an interrupt or whatever when it does so). The returned
values are: *DIVLOG2 -- log2 of the desired clock divider and *COUNT
-- the counter compare value to use. Returns true if it was possible
to find a reasonable value, otherwise false (and the other return
values will be set to be as good as possible). */
extern int calc_counter_params (unsigned long base_freq,
unsigned long rate,
unsigned min_divlog2, unsigned max_divlog2,
unsigned counter_size,
unsigned *divlog2, unsigned *count);
#endif /* __V850_V850E_UTILS_H__ */
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