Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * include/asm-v850/v850e_utils.h -- Utility functions associated with |
| 3 | * V850E CPUs |
| 4 | * |
| 5 | * Copyright (C) 2001,03 NEC Electronics Corporation |
| 6 | * Copyright (C) 2001,03 Miles Bader <miles@gnu.org> |
| 7 | * |
| 8 | * This file is subject to the terms and conditions of the GNU General |
| 9 | * Public License. See the file COPYING in the main directory of this |
| 10 | * archive for more details. |
| 11 | * |
| 12 | * Written by Miles Bader <miles@gnu.org> |
| 13 | */ |
| 14 | |
| 15 | #ifndef __V850_V850E_UTILS_H__ |
| 16 | #define __V850_V850E_UTILS_H__ |
| 17 | |
| 18 | /* Calculate counter clock-divider and count values to attain the |
| 19 | desired frequency RATE from the base frequency BASE_FREQ. The |
| 20 | counter is expected to have a clock-divider, which can divide the |
| 21 | system cpu clock by a power of two value from MIN_DIVLOG2 to |
| 22 | MAX_DIV_LOG2, and a word-size of COUNTER_SIZE bits (the counter |
| 23 | counts up and resets whenever it's equal to the compare register, |
| 24 | generating an interrupt or whatever when it does so). The returned |
| 25 | values are: *DIVLOG2 -- log2 of the desired clock divider and *COUNT |
| 26 | -- the counter compare value to use. Returns true if it was possible |
| 27 | to find a reasonable value, otherwise false (and the other return |
| 28 | values will be set to be as good as possible). */ |
| 29 | extern int calc_counter_params (unsigned long base_freq, |
| 30 | unsigned long rate, |
| 31 | unsigned min_divlog2, unsigned max_divlog2, |
| 32 | unsigned counter_size, |
| 33 | unsigned *divlog2, unsigned *count); |
| 34 | |
| 35 | #endif /* __V850_V850E_UTILS_H__ */ |