xref: /freebsd/sys/arm64/freescale/imx/clk/imx_clk_frac_pll.c (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2020 Oleksandr Tymoshenko <gonzo@FreeBSD.org>
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 ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
20  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
21  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
22  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23  * 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  * $FreeBSD$
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/bus.h>
36 
37 #include <dev/extres/clk/clk.h>
38 
39 #include <arm64/freescale/imx/clk/imx_clk_frac_pll.h>
40 
41 #include "clkdev_if.h"
42 
43 struct imx_clk_frac_pll_sc {
44 	uint32_t	offset;
45 };
46 
47 #define	WRITE4(_clk, off, val)						\
48 	CLKDEV_WRITE_4(clknode_get_device(_clk), off, val)
49 #define	READ4(_clk, off, val)						\
50 	CLKDEV_READ_4(clknode_get_device(_clk), off, val)
51 #define	DEVICE_LOCK(_clk)						\
52 	CLKDEV_DEVICE_LOCK(clknode_get_device(_clk))
53 #define	DEVICE_UNLOCK(_clk)						\
54 	CLKDEV_DEVICE_UNLOCK(clknode_get_device(_clk))
55 
56 #define	CFG0	0
57 #define	 CFG0_PLL_LOCK		(1 << 31)
58 #define	 CFG0_PD		(1 << 19)
59 #define	 CFG0_BYPASS		(1 << 14)
60 #define	 CFG0_NEWDIV_VAL	(1 << 12)
61 #define	 CFG0_NEWDIV_ACK	(1 << 11)
62 #define	 CFG0_OUTPUT_DIV_MASK	(0x1f << 0)
63 #define	 CFG0_OUTPUT_DIV_SHIFT	0
64 #define	CFG1	4
65 #define	 CFG1_FRAC_DIV_MASK	(0xffffff << 7)
66 #define	 CFG1_FRAC_DIV_SHIFT	7
67 #define	 CFG1_INT_DIV_MASK	(0x7f << 0)
68 #define	 CFG1_INT_DIV_SHIFT	0
69 
70 #if 0
71 #define	dprintf(format, arg...)						\
72 	printf("%s:(%s)" format, __func__, clknode_get_name(clk), arg)
73 #else
74 #define	dprintf(format, arg...)
75 #endif
76 
77 static int
78 imx_clk_frac_pll_init(struct clknode *clk, device_t dev)
79 {
80 
81 	clknode_init_parent_idx(clk, 0);
82 	return (0);
83 }
84 
85 static int
86 imx_clk_frac_pll_set_gate(struct clknode *clk, bool enable)
87 {
88 	struct imx_clk_frac_pll_sc *sc;
89 	uint32_t cfg0;
90 	int timeout;
91 
92 	sc = clknode_get_softc(clk);
93 
94 	DEVICE_LOCK(clk);
95 	READ4(clk, sc->offset + CFG0, &cfg0);
96 	if (enable)
97 		cfg0 &= ~(CFG0_PD);
98 	else
99 		cfg0 |= CFG0_PD;
100 	WRITE4(clk, sc->offset + CFG0, cfg0);
101 
102 	/* Wait for PLL to lock */
103 	if (enable && ((cfg0 & CFG0_BYPASS) == 0)) {
104 		for (timeout = 1000; timeout; timeout--) {
105 			READ4(clk, sc->offset + CFG0, &cfg0);
106 			if (cfg0 & CFG0_PLL_LOCK)
107 				break;
108 			DELAY(1);
109 		}
110 	}
111 
112 	DEVICE_UNLOCK(clk);
113 
114 	return (0);
115 }
116 
117 static int
118 imx_clk_frac_pll_recalc(struct clknode *clk, uint64_t *freq)
119 {
120 	struct imx_clk_frac_pll_sc *sc;
121 	uint32_t cfg0, cfg1;
122 	uint64_t div, divfi, divff, divf_val;
123 
124 	sc = clknode_get_softc(clk);
125 
126 	DEVICE_LOCK(clk);
127 	READ4(clk, sc->offset + CFG0, &cfg0);
128 	READ4(clk, sc->offset + CFG1, &cfg1);
129 	DEVICE_UNLOCK(clk);
130 
131 	div = (cfg0 & CFG0_OUTPUT_DIV_MASK) >> CFG0_OUTPUT_DIV_SHIFT;
132 	div = (div + 1) * 2;
133 	divff = (cfg1 & CFG1_FRAC_DIV_MASK) >> CFG1_FRAC_DIV_SHIFT;
134 	divfi = (cfg1 & CFG1_INT_DIV_MASK) >> CFG1_INT_DIV_SHIFT;
135 
136 	/* PLL is bypassed */
137 	if (cfg0 & CFG0_BYPASS)
138 		return (0);
139 
140 	divf_val = 1 + divfi + (divff/0x1000000);
141 	*freq = *freq * 8 * divf_val / div;
142 
143 	return (0);
144 }
145 
146 static clknode_method_t imx_clk_frac_pll_clknode_methods[] = {
147 	/* Device interface */
148 	CLKNODEMETHOD(clknode_init,		imx_clk_frac_pll_init),
149 	CLKNODEMETHOD(clknode_set_gate,		imx_clk_frac_pll_set_gate),
150 	CLKNODEMETHOD(clknode_recalc_freq,	imx_clk_frac_pll_recalc),
151 	CLKNODEMETHOD_END
152 };
153 
154 DEFINE_CLASS_1(imx_clk_frac_pll_clknode, imx_clk_frac_pll_clknode_class,
155     imx_clk_frac_pll_clknode_methods, sizeof(struct imx_clk_frac_pll_sc),
156     clknode_class);
157 
158 int
159 imx_clk_frac_pll_register(struct clkdom *clkdom,
160     struct imx_clk_frac_pll_def *clkdef)
161 {
162 	struct clknode *clk;
163 	struct imx_clk_frac_pll_sc *sc;
164 
165 	clk = clknode_create(clkdom, &imx_clk_frac_pll_clknode_class,
166 	    &clkdef->clkdef);
167 	if (clk == NULL)
168 		return (1);
169 
170 	sc = clknode_get_softc(clk);
171 
172 	sc->offset = clkdef->offset;
173 
174 	clknode_register(clkdom, clk);
175 
176 	return (0);
177 }
178