xref: /freebsd/sys/dev/clk/clk_fixed.h (revision 6580f5c38dd5b01aeeaed16b370f1a12423437f0)
1 /*-
2  * Copyright 2016 Michal Meloun <mmel@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #ifndef _DEV_CLK_FIXED_H_
28 #define	_DEV_CLK_FIXED_H_
29 
30 #include <dev/clk/clk.h>
31 
32 /*
33  * A fixed clock can represent several different real-world objects, including
34  * an oscillator with a fixed output frequency, a fixed divider (multiplier and
35  * divisor must both be > 0), or a phase-fractional divider within a PLL
36  * (however the code currently divides first, then multiplies, potentially
37  * leading to different roundoff errors than the hardware PLL).
38  */
39 
40 struct clk_fixed_def {
41 	struct clknode_init_def clkdef;
42 	uint64_t		freq;
43 	uint32_t		mult;
44 	uint32_t		div;
45 	int			fixed_flags;
46 };
47 
48 int clknode_fixed_register(struct clkdom *clkdom, struct clk_fixed_def *clkdef);
49 
50 #endif	/*_DEV_CLK_FIXED_H_*/
51