36 lines
1.4 KiB
C
36 lines
1.4 KiB
C
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/*
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* include/asm-v850/v850e_utils.h -- Utility functions associated with
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* V850E CPUs
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*
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* Copyright (C) 2001,03 NEC Electronics Corporation
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* Copyright (C) 2001,03 Miles Bader <miles@gnu.org>
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*
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* This file is subject to the terms and conditions of the GNU General
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* Public License. See the file COPYING in the main directory of this
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* archive for more details.
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*
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* Written by Miles Bader <miles@gnu.org>
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*/
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#ifndef __V850_V850E_UTILS_H__
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#define __V850_V850E_UTILS_H__
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/* Calculate counter clock-divider and count values to attain the
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desired frequency RATE from the base frequency BASE_FREQ. The
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counter is expected to have a clock-divider, which can divide the
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system cpu clock by a power of two value from MIN_DIVLOG2 to
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MAX_DIV_LOG2, and a word-size of COUNTER_SIZE bits (the counter
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counts up and resets whenever it's equal to the compare register,
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generating an interrupt or whatever when it does so). The returned
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values are: *DIVLOG2 -- log2 of the desired clock divider and *COUNT
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-- the counter compare value to use. Returns true if it was possible
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to find a reasonable value, otherwise false (and the other return
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values will be set to be as good as possible). */
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extern int calc_counter_params (unsigned long base_freq,
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unsigned long rate,
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unsigned min_divlog2, unsigned max_divlog2,
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unsigned counter_size,
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unsigned *divlog2, unsigned *count);
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#endif /* __V850_V850E_UTILS_H__ */
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