clk_gate.c revision 294660 
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/cdefs.h>
28__FBSDID("$FreeBSD: head/sys/dev/extres/clk/clk_gate.c 294660 2016-01-24 11:00:38Z mmel $");
29
30
31#include <sys/param.h>
32#include <sys/conf.h>
33#include <sys/bus.h>
34#include <sys/kernel.h>
35#include <sys/systm.h>
36
37#include <machine/bus.h>
38
39#include <dev/extres/clk/clk_gate.h>
40
41#include "clkdev_if.h"
42
43#define	WR4(_clk, off, val)						\
44	CLKDEV_WRITE_4(clknode_get_device(_clk), off, val)
45#define	RD4(_clk, off, val)						\
46	CLKDEV_READ_4(clknode_get_device(_clk), off, val)
47#define	MD4(_clk, off, clr, set )					\
48	CLKDEV_MODIFY_4(clknode_get_device(_clk), off, clr, set)
49
50
51static int clknode_gate_init(struct clknode *clk, device_t dev);
52static int clknode_gate_set_gate(struct clknode *clk, bool enable);
53struct clknode_gate_sc {
54	uint32_t	offset;
55	uint32_t	shift;
56	uint32_t	mask;
57	uint32_t	on_value;
58	uint32_t	off_value;
59	int		gate_flags;
60	bool		ungated;
61};
62
63static clknode_method_t clknode_gate_methods[] = {
64	/* Device interface */
65	CLKNODEMETHOD(clknode_init,	clknode_gate_init),
66	CLKNODEMETHOD(clknode_set_gate,	clknode_gate_set_gate),
67	CLKNODEMETHOD_END
68};
69DEFINE_CLASS_1(clknode_gate, clknode_gate_class, clknode_gate_methods,
70   sizeof(struct clknode_gate_sc), clknode_class);
71
72static int
73clknode_gate_init(struct clknode *clk, device_t dev)
74{
75	uint32_t reg;
76	struct clknode_gate_sc *sc;
77	int rv;
78
79	sc = clknode_get_softc(clk);
80	rv = RD4(clk, sc->offset, &reg);
81	if (rv != 0)
82		return (rv);
83	reg = (reg >> sc->shift) & sc->mask;
84	sc->ungated = reg == sc->on_value ? 1 : 0;
85	clknode_init_parent_idx(clk, 0);
86	return(0);
87}
88
89static int
90clknode_gate_set_gate(struct clknode *clk, bool enable)
91{
92	uint32_t reg;
93	struct clknode_gate_sc *sc;
94	int rv;
95
96	sc = clknode_get_softc(clk);
97	sc->ungated = enable;
98	rv = MD4(clk, sc->offset, sc->mask << sc->shift,
99	    (sc->ungated ? sc->on_value : sc->off_value) << sc->shift);
100	if (rv != 0)
101		return (rv);
102	RD4(clk, sc->offset, &reg);
103	return(0);
104}
105
106int
107clknode_gate_register(struct clkdom *clkdom, struct clk_gate_def *clkdef)
108{
109	struct clknode *clk;
110	struct clknode_gate_sc *sc;
111
112	clk = clknode_create(clkdom, &clknode_gate_class, &clkdef->clkdef);
113	if (clk == NULL)
114		return (1);
115
116	sc = clknode_get_softc(clk);
117	sc->offset = clkdef->offset;
118	sc->shift = clkdef->shift;
119	sc->mask =  clkdef->mask;
120	sc->on_value = clkdef->on_value;
121	sc->off_value = clkdef->off_value;
122	sc->gate_flags = clkdef->gate_flags;
123
124	clknode_register(clkdom, clk);
125	return (0);
126}
127