xref: /netbsd-src/sys/arch/arm/amlogic/meson_clk_gate.c (revision 7e38c880e6b36d84c377184be7355e456c934ffd)
1 /* $NetBSD: meson_clk_gate.c,v 1.2 2019/02/25 19:30:17 jmcneill Exp $ */
2 
3 /*-
4  * Copyright (c) 2017-2019 Jared McNeill <jmcneill@invisible.ca>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: meson_clk_gate.c,v 1.2 2019/02/25 19:30:17 jmcneill Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 
35 #include <dev/clk/clk_backend.h>
36 
37 #include <arm/amlogic/meson_clk.h>
38 
39 int
meson_clk_gate_enable(struct meson_clk_softc * sc,struct meson_clk_clk * clk,int enable)40 meson_clk_gate_enable(struct meson_clk_softc *sc, struct meson_clk_clk *clk,
41     int enable)
42 {
43 	struct meson_clk_gate *gate = &clk->u.gate;
44 	uint32_t val;
45 	int set;
46 
47 	KASSERT(clk->type == MESON_CLK_GATE);
48 
49 	set = (gate->flags & MESON_CLK_GATE_SET_TO_DISABLE) ? !enable : enable;
50 
51 	CLK_LOCK(sc);
52 
53 	val = CLK_READ(sc, gate->reg);
54 	if (set)
55 		val |= gate->mask;
56 	else
57 		val &= ~gate->mask;
58 	CLK_WRITE(sc, gate->reg, val);
59 
60 	CLK_UNLOCK(sc);
61 
62 	return 0;
63 }
64 
65 const char *
meson_clk_gate_get_parent(struct meson_clk_softc * sc,struct meson_clk_clk * clk)66 meson_clk_gate_get_parent(struct meson_clk_softc *sc, struct meson_clk_clk *clk)
67 {
68 	struct meson_clk_gate *gate = &clk->u.gate;
69 
70 	KASSERT(clk->type == MESON_CLK_GATE);
71 
72 	return gate->parent;
73 }
74