xref: /freebsd/sys/arm64/freescale/imx/clk/imx_clk_frac_pll.c (revision b3e7694832e81d7a904a10f525f8797b753bf0d3)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/bus.h>
34 
35 #include <dev/extres/clk/clk.h>
36 
37 #include <arm64/freescale/imx/clk/imx_clk_frac_pll.h>
38 
39 #include "clkdev_if.h"
40 
41 struct imx_clk_frac_pll_sc {
42 	uint32_t	offset;
43 };
44 
45 #define	WRITE4(_clk, off, val)						\
46 	CLKDEV_WRITE_4(clknode_get_device(_clk), off, val)
47 #define	READ4(_clk, off, val)						\
48 	CLKDEV_READ_4(clknode_get_device(_clk), off, val)
49 #define	DEVICE_LOCK(_clk)						\
50 	CLKDEV_DEVICE_LOCK(clknode_get_device(_clk))
51 #define	DEVICE_UNLOCK(_clk)						\
52 	CLKDEV_DEVICE_UNLOCK(clknode_get_device(_clk))
53 
54 #define	CFG0	0
55 #define	 CFG0_PLL_LOCK		(1 << 31)
56 #define	 CFG0_PD		(1 << 19)
57 #define	 CFG0_BYPASS		(1 << 14)
58 #define	 CFG0_NEWDIV_VAL	(1 << 12)
59 #define	 CFG0_NEWDIV_ACK	(1 << 11)
60 #define	 CFG0_OUTPUT_DIV_MASK	(0x1f << 0)
61 #define	 CFG0_OUTPUT_DIV_SHIFT	0
62 #define	CFG1	4
63 #define	 CFG1_FRAC_DIV_MASK	(0xffffff << 7)
64 #define	 CFG1_FRAC_DIV_SHIFT	7
65 #define	 CFG1_INT_DIV_MASK	(0x7f << 0)
66 #define	 CFG1_INT_DIV_SHIFT	0
67 
68 #if 0
69 #define	dprintf(format, arg...)						\
70 	printf("%s:(%s)" format, __func__, clknode_get_name(clk), arg)
71 #else
72 #define	dprintf(format, arg...)
73 #endif
74 
75 static int
76 imx_clk_frac_pll_init(struct clknode *clk, device_t dev)
77 {
78 
79 	clknode_init_parent_idx(clk, 0);
80 	return (0);
81 }
82 
83 static int
84 imx_clk_frac_pll_set_gate(struct clknode *clk, bool enable)
85 {
86 	struct imx_clk_frac_pll_sc *sc;
87 	uint32_t cfg0;
88 	int timeout;
89 
90 	sc = clknode_get_softc(clk);
91 
92 	DEVICE_LOCK(clk);
93 	READ4(clk, sc->offset + CFG0, &cfg0);
94 	if (enable)
95 		cfg0 &= ~(CFG0_PD);
96 	else
97 		cfg0 |= CFG0_PD;
98 	WRITE4(clk, sc->offset + CFG0, cfg0);
99 
100 	/* Wait for PLL to lock */
101 	if (enable && ((cfg0 & CFG0_BYPASS) == 0)) {
102 		for (timeout = 1000; timeout; timeout--) {
103 			READ4(clk, sc->offset + CFG0, &cfg0);
104 			if (cfg0 & CFG0_PLL_LOCK)
105 				break;
106 			DELAY(1);
107 		}
108 	}
109 
110 	DEVICE_UNLOCK(clk);
111 
112 	return (0);
113 }
114 
115 static int
116 imx_clk_frac_pll_recalc(struct clknode *clk, uint64_t *freq)
117 {
118 	struct imx_clk_frac_pll_sc *sc;
119 	uint32_t cfg0, cfg1;
120 	uint64_t div, divfi, divff, divf_val;
121 
122 	sc = clknode_get_softc(clk);
123 
124 	DEVICE_LOCK(clk);
125 	READ4(clk, sc->offset + CFG0, &cfg0);
126 	READ4(clk, sc->offset + CFG1, &cfg1);
127 	DEVICE_UNLOCK(clk);
128 
129 	div = (cfg0 & CFG0_OUTPUT_DIV_MASK) >> CFG0_OUTPUT_DIV_SHIFT;
130 	div = (div + 1) * 2;
131 	divff = (cfg1 & CFG1_FRAC_DIV_MASK) >> CFG1_FRAC_DIV_SHIFT;
132 	divfi = (cfg1 & CFG1_INT_DIV_MASK) >> CFG1_INT_DIV_SHIFT;
133 
134 	/* PLL is bypassed */
135 	if (cfg0 & CFG0_BYPASS)
136 		return (0);
137 
138 	divf_val = 1 + divfi + (divff/0x1000000);
139 	*freq = *freq * 8 * divf_val / div;
140 
141 	return (0);
142 }
143 
144 static clknode_method_t imx_clk_frac_pll_clknode_methods[] = {
145 	/* Device interface */
146 	CLKNODEMETHOD(clknode_init,		imx_clk_frac_pll_init),
147 	CLKNODEMETHOD(clknode_set_gate,		imx_clk_frac_pll_set_gate),
148 	CLKNODEMETHOD(clknode_recalc_freq,	imx_clk_frac_pll_recalc),
149 	CLKNODEMETHOD_END
150 };
151 
152 DEFINE_CLASS_1(imx_clk_frac_pll_clknode, imx_clk_frac_pll_clknode_class,
153     imx_clk_frac_pll_clknode_methods, sizeof(struct imx_clk_frac_pll_sc),
154     clknode_class);
155 
156 int
157 imx_clk_frac_pll_register(struct clkdom *clkdom,
158     struct imx_clk_frac_pll_def *clkdef)
159 {
160 	struct clknode *clk;
161 	struct imx_clk_frac_pll_sc *sc;
162 
163 	clk = clknode_create(clkdom, &imx_clk_frac_pll_clknode_class,
164 	    &clkdef->clkdef);
165 	if (clk == NULL)
166 		return (1);
167 
168 	sc = clknode_get_softc(clk);
169 
170 	sc->offset = clkdef->offset;
171 
172 	clknode_register(clkdom, clk);
173 
174 	return (0);
175 }
176