xref: /freebsd/sys/dev/clk/clk_mux.c (revision 5c2bc3db201a4fe8d7911cf816bea104d5dc2138)
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 #include <sys/param.h>
28 #include <sys/conf.h>
29 #include <sys/bus.h>
30 #include <sys/kernel.h>
31 #include <sys/systm.h>
32 
33 #include <machine/bus.h>
34 
35 #include <dev/clk/clk_mux.h>
36 
37 #include "clkdev_if.h"
38 
39 #define	WR4(_clk, off, val)						\
40 	CLKDEV_WRITE_4(clknode_get_device(_clk), off, val)
41 #define	RD4(_clk, off, val)						\
42 	CLKDEV_READ_4(clknode_get_device(_clk), off, val)
43 #define	MD4(_clk, off, clr, set )					\
44 	CLKDEV_MODIFY_4(clknode_get_device(_clk), off, clr, set)
45 #define	DEVICE_LOCK(_clk)							\
46 	CLKDEV_DEVICE_LOCK(clknode_get_device(_clk))
47 #define	DEVICE_UNLOCK(_clk)						\
48 	CLKDEV_DEVICE_UNLOCK(clknode_get_device(_clk))
49 
50 static int clknode_mux_init(struct clknode *clk, device_t dev);
51 static int clknode_mux_set_mux(struct clknode *clk, int idx);
52 
53 struct clknode_mux_sc {
54 	uint32_t	offset;
55 	uint32_t	shift;
56 	uint32_t	mask;
57 	int		mux_flags;
58 };
59 
60 static clknode_method_t clknode_mux_methods[] = {
61 	/* Device interface */
62 	CLKNODEMETHOD(clknode_init, 	clknode_mux_init),
63 	CLKNODEMETHOD(clknode_set_mux, 	clknode_mux_set_mux),
64 	CLKNODEMETHOD_END
65 };
66 DEFINE_CLASS_1(clknode_mux, clknode_mux_class, clknode_mux_methods,
67    sizeof(struct clknode_mux_sc), clknode_class);
68 
69 
70 static int
71 clknode_mux_init(struct clknode *clk, device_t dev)
72 {
73 	uint32_t reg;
74 	struct clknode_mux_sc *sc;
75 	int rv;
76 
77 	sc = clknode_get_softc(clk);
78 
79 	DEVICE_LOCK(clk);
80 	rv = RD4(clk, sc->offset, &reg);
81 	DEVICE_UNLOCK(clk);
82 	if (rv != 0) {
83 		return (rv);
84 	}
85 	reg = (reg >> sc->shift) & sc->mask;
86 	clknode_init_parent_idx(clk, reg);
87 	return(0);
88 }
89 
90 static int
91 clknode_mux_set_mux(struct clknode *clk, int idx)
92 {
93 	uint32_t reg;
94 	struct clknode_mux_sc *sc;
95 	int rv;
96 
97 	sc = clknode_get_softc(clk);
98 
99 	DEVICE_LOCK(clk);
100 	rv = MD4(clk, sc->offset, sc->mask << sc->shift,
101 	    (idx & sc->mask) << sc->shift);
102 	if (rv != 0) {
103 		DEVICE_UNLOCK(clk);
104 		return (rv);
105 	}
106 	RD4(clk, sc->offset, &reg);
107 	DEVICE_UNLOCK(clk);
108 
109 	return(0);
110 }
111 
112 int
113 clknode_mux_register(struct clkdom *clkdom, struct clk_mux_def *clkdef)
114 {
115 	struct clknode *clk;
116 	struct clknode_mux_sc *sc;
117 
118 	clk = clknode_create(clkdom, &clknode_mux_class, &clkdef->clkdef);
119 	if (clk == NULL)
120 		return (1);
121 
122 	sc = clknode_get_softc(clk);
123 	sc->offset = clkdef->offset;
124 	sc->shift = clkdef->shift;
125 	sc->mask =  (1 << clkdef->width) - 1;
126 	sc->mux_flags = clkdef->mux_flags;
127 
128 	clknode_register(clkdom, clk);
129 	return (0);
130 }
131