xref: /freebsd/sys/arm64/freescale/imx/clk/imx_clk_frac_pll.c (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
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/param.h>
29 #include <sys/systm.h>
30 #include <sys/bus.h>
31 
32 #include <dev/extres/clk/clk.h>
33 
34 #include <arm64/freescale/imx/clk/imx_clk_frac_pll.h>
35 
36 #include "clkdev_if.h"
37 
38 struct imx_clk_frac_pll_sc {
39 	uint32_t	offset;
40 };
41 
42 #define	WRITE4(_clk, off, val)						\
43 	CLKDEV_WRITE_4(clknode_get_device(_clk), off, val)
44 #define	READ4(_clk, off, val)						\
45 	CLKDEV_READ_4(clknode_get_device(_clk), off, val)
46 #define	DEVICE_LOCK(_clk)						\
47 	CLKDEV_DEVICE_LOCK(clknode_get_device(_clk))
48 #define	DEVICE_UNLOCK(_clk)						\
49 	CLKDEV_DEVICE_UNLOCK(clknode_get_device(_clk))
50 
51 #define	CFG0	0
52 #define	 CFG0_PLL_LOCK		(1 << 31)
53 #define	 CFG0_PD		(1 << 19)
54 #define	 CFG0_BYPASS		(1 << 14)
55 #define	 CFG0_NEWDIV_VAL	(1 << 12)
56 #define	 CFG0_NEWDIV_ACK	(1 << 11)
57 #define	 CFG0_OUTPUT_DIV_MASK	(0x1f << 0)
58 #define	 CFG0_OUTPUT_DIV_SHIFT	0
59 #define	CFG1	4
60 #define	 CFG1_FRAC_DIV_MASK	(0xffffff << 7)
61 #define	 CFG1_FRAC_DIV_SHIFT	7
62 #define	 CFG1_INT_DIV_MASK	(0x7f << 0)
63 #define	 CFG1_INT_DIV_SHIFT	0
64 
65 #if 0
66 #define	dprintf(format, arg...)						\
67 	printf("%s:(%s)" format, __func__, clknode_get_name(clk), arg)
68 #else
69 #define	dprintf(format, arg...)
70 #endif
71 
72 static int
73 imx_clk_frac_pll_init(struct clknode *clk, device_t dev)
74 {
75 
76 	clknode_init_parent_idx(clk, 0);
77 	return (0);
78 }
79 
80 static int
81 imx_clk_frac_pll_set_gate(struct clknode *clk, bool enable)
82 {
83 	struct imx_clk_frac_pll_sc *sc;
84 	uint32_t cfg0;
85 	int timeout;
86 
87 	sc = clknode_get_softc(clk);
88 
89 	DEVICE_LOCK(clk);
90 	READ4(clk, sc->offset + CFG0, &cfg0);
91 	if (enable)
92 		cfg0 &= ~(CFG0_PD);
93 	else
94 		cfg0 |= CFG0_PD;
95 	WRITE4(clk, sc->offset + CFG0, cfg0);
96 
97 	/* Wait for PLL to lock */
98 	if (enable && ((cfg0 & CFG0_BYPASS) == 0)) {
99 		for (timeout = 1000; timeout; timeout--) {
100 			READ4(clk, sc->offset + CFG0, &cfg0);
101 			if (cfg0 & CFG0_PLL_LOCK)
102 				break;
103 			DELAY(1);
104 		}
105 	}
106 
107 	DEVICE_UNLOCK(clk);
108 
109 	return (0);
110 }
111 
112 static int
113 imx_clk_frac_pll_recalc(struct clknode *clk, uint64_t *freq)
114 {
115 	struct imx_clk_frac_pll_sc *sc;
116 	uint32_t cfg0, cfg1;
117 	uint64_t div, divfi, divff, divf_val;
118 
119 	sc = clknode_get_softc(clk);
120 
121 	DEVICE_LOCK(clk);
122 	READ4(clk, sc->offset + CFG0, &cfg0);
123 	READ4(clk, sc->offset + CFG1, &cfg1);
124 	DEVICE_UNLOCK(clk);
125 
126 	div = (cfg0 & CFG0_OUTPUT_DIV_MASK) >> CFG0_OUTPUT_DIV_SHIFT;
127 	div = (div + 1) * 2;
128 	divff = (cfg1 & CFG1_FRAC_DIV_MASK) >> CFG1_FRAC_DIV_SHIFT;
129 	divfi = (cfg1 & CFG1_INT_DIV_MASK) >> CFG1_INT_DIV_SHIFT;
130 
131 	/* PLL is bypassed */
132 	if (cfg0 & CFG0_BYPASS)
133 		return (0);
134 
135 	divf_val = 1 + divfi + (divff/0x1000000);
136 	*freq = *freq * 8 * divf_val / div;
137 
138 	return (0);
139 }
140 
141 static clknode_method_t imx_clk_frac_pll_clknode_methods[] = {
142 	/* Device interface */
143 	CLKNODEMETHOD(clknode_init,		imx_clk_frac_pll_init),
144 	CLKNODEMETHOD(clknode_set_gate,		imx_clk_frac_pll_set_gate),
145 	CLKNODEMETHOD(clknode_recalc_freq,	imx_clk_frac_pll_recalc),
146 	CLKNODEMETHOD_END
147 };
148 
149 DEFINE_CLASS_1(imx_clk_frac_pll_clknode, imx_clk_frac_pll_clknode_class,
150     imx_clk_frac_pll_clknode_methods, sizeof(struct imx_clk_frac_pll_sc),
151     clknode_class);
152 
153 int
154 imx_clk_frac_pll_register(struct clkdom *clkdom,
155     struct imx_clk_frac_pll_def *clkdef)
156 {
157 	struct clknode *clk;
158 	struct imx_clk_frac_pll_sc *sc;
159 
160 	clk = clknode_create(clkdom, &imx_clk_frac_pll_clknode_class,
161 	    &clkdef->clkdef);
162 	if (clk == NULL)
163 		return (1);
164 
165 	sc = clknode_get_softc(clk);
166 
167 	sc->offset = clkdef->offset;
168 
169 	clknode_register(clkdom, clk);
170 
171 	return (0);
172 }
173