xref: /freebsd/sys/arm/mv/clk/a37x0_tbg_pll.c (revision be82b3a0bf72ed3b5f01ac9fcd8dcd3802e3c742)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2021 Semihalf.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/param.h>
29 #include <sys/bus.h>
30 #include <sys/rman.h>
31 #include <machine/bus.h>
32 
33 #include <dev/clk/clk.h>
34 
35 #include <dev/ofw/ofw_bus.h>
36 #include <dev/ofw/ofw_bus_subr.h>
37 
38 #include "clkdev_if.h"
39 
40 #include "a37x0_tbg_pll.h"
41 
42 #define RD4(_clk, offset, val)			\
43 	CLKDEV_READ_4(clknode_get_device(_clk), offset, val)
44 
45 struct a37x0_tbg_pll_softc {
46 	struct a37x0_tbg_pll_reg_def		vcodiv;
47 	struct a37x0_tbg_pll_reg_def		refdiv;
48 	struct a37x0_tbg_pll_reg_def		fbdiv;
49 	struct a37x0_tbg_pll_reg_def		tbg_bypass;
50 };
51 
52 static int
a37x0_tbg_pll_recalc_freq(struct clknode * clk,uint64_t * freq)53 a37x0_tbg_pll_recalc_freq(struct clknode *clk, uint64_t *freq)
54 {
55 	struct a37x0_tbg_pll_softc *sc;
56 	uint32_t vcodiv, fbdiv, refdiv;
57 	unsigned int val;
58 
59 	sc = clknode_get_softc(clk);
60 
61 	RD4(clk, sc->tbg_bypass.offset, &val);
62 	if ((val >> sc->tbg_bypass.shift) & sc->tbg_bypass.mask)
63 		return 0;
64 
65 	RD4(clk, sc->vcodiv.offset, &val);
66 	vcodiv = 1 << ((val >> sc->vcodiv.shift) & sc->vcodiv.mask);
67 
68 	RD4(clk, sc->refdiv.offset, &val);
69 	refdiv = (val >> sc->refdiv.shift) & sc->refdiv.mask;
70 
71 	RD4(clk, sc->fbdiv.offset, &val);
72 	fbdiv = (val >> sc->fbdiv.shift) & sc->fbdiv.mask;
73 
74 	if (refdiv == 0)
75 		refdiv = 1;
76 
77 	*freq = *freq * (fbdiv / refdiv) * 4;
78 	*freq /= vcodiv;
79 
80 	return (0);
81 }
82 
83 static int
a37x0_tbg_pll_init(struct clknode * clk,device_t dev)84 a37x0_tbg_pll_init(struct clknode *clk, device_t dev)
85 {
86 
87 	clknode_init_parent_idx(clk, 0);
88 
89 	return (0);
90 }
91 
92 static clknode_method_t a37x0_tbg_pll_clknode_methods[] = {
93 	CLKNODEMETHOD(clknode_recalc_freq,	a37x0_tbg_pll_recalc_freq),
94 	CLKNODEMETHOD(clknode_init,		a37x0_tbg_pll_init),
95 
96 	CLKNODEMETHOD_END
97 };
98 
99 DEFINE_CLASS_1(a37x0_tbg_pll__clknode, a37x0_tbg_pll_clknode_class,
100     a37x0_tbg_pll_clknode_methods, sizeof(struct a37x0_tbg_pll_softc),
101     clknode_class);
102 
103 int
a37x0_tbg_pll_clk_register(struct clkdom * clkdom,const struct a37x0_tbg_pll_clk_def * clkdef)104 a37x0_tbg_pll_clk_register(struct clkdom *clkdom,
105     const struct a37x0_tbg_pll_clk_def *clkdef)
106 {
107 	struct a37x0_tbg_pll_softc *sc;
108 	struct clknode *clk;
109 
110 	clk = clknode_create(clkdom, &a37x0_tbg_pll_clknode_class,
111 	    &clkdef->clkdef);
112 
113 	if (clk == NULL)
114 		return (1);
115 
116 	sc = clknode_get_softc(clk);
117 
118 	sc->vcodiv = clkdef->vcodiv;
119 	sc->refdiv = clkdef->refdiv;
120 	sc->fbdiv = clkdef->fbdiv;
121 	sc->tbg_bypass = clkdef->tbg_bypass;
122 
123 	if (clknode_register(clkdom, clk) == NULL)
124 		return (1);
125 
126 	return (0);
127 }
128