xref: /freebsd/sys/dev/clk/xilinx/zynqmp_clk_div.c (revision f81cdf24ba5436367377f7c8e8f51f6df2a75ca7)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2023 Beckhoff Automation GmbH & Co. KG
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/cdefs.h>
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 
34 #include <dev/clk/clk.h>
35 
36 #include <dev/clk/xilinx/zynqmp_clk_div.h>
37 
38 #include "clkdev_if.h"
39 #include "zynqmp_firmware_if.h"
40 
41 #define DIV_ROUND_CLOSEST(n, d)	(((n) + (d) / 2) / (d))
42 
43 struct zynqmp_clk_div_softc {
44 	device_t			firmware;
45 	enum zynqmp_clk_div_type	type;
46 	uint32_t			id;
47 };
48 
49 static int
50 zynqmp_clk_div_init(struct clknode *clk, device_t dev)
51 {
52 
53 	clknode_init_parent_idx(clk, 0);
54 	return (0);
55 }
56 
57 static int
58 zynqmp_clk_div_recalc(struct clknode *clk, uint64_t *freq)
59 {
60 	struct zynqmp_clk_div_softc *sc;
61 	uint32_t div;
62 	int rv;
63 
64 	sc = clknode_get_softc(clk);
65 	rv = ZYNQMP_FIRMWARE_CLOCK_GETDIVIDER(sc->firmware, sc->id, &div);
66 	if (rv != 0) {
67 		printf("%s: Error while getting divider for %s\n",
68 		    __func__,
69 		    clknode_get_name(clk));
70 		return (EINVAL);
71 	}
72 
73 	if (sc->type == CLK_DIV_TYPE_DIV0)
74 		div &= 0xFFFF;
75 	else
76 		div = div >> 16;
77 	*freq = howmany((unsigned long long)*freq, div + 1);
78 	return (0);
79 }
80 
81 static int
82 zynqmp_clk_div_set_freq(struct clknode *clk, uint64_t fparent, uint64_t *fout,
83     int flags, int *stop)
84 {
85 	struct zynqmp_clk_div_softc *sc;
86 	uint32_t div;
87 	int rv;
88 
89 	sc = clknode_get_softc(clk);
90 
91 	div = DIV_ROUND_CLOSEST(fparent, *fout);
92 	if (sc->type == CLK_DIV_TYPE_DIV0) {
93 		div &= 0xFFFF;
94 		div |= 0xFFFF << 16;
95 	} else {
96 		div <<= 16;
97 		div |= 0xFFFF;
98 	}
99 
100 	rv = ZYNQMP_FIRMWARE_CLOCK_SETDIVIDER(sc->firmware, sc->id, div);
101 	if (rv != 0) {
102 		printf("%s: Error while setting divider for %s\n",
103 		    __func__,
104 		    clknode_get_name(clk));
105 		return (EINVAL);
106 	}
107 
108 	return (rv);
109 }
110 
111 static clknode_method_t zynqmp_clk_div_clknode_methods[] = {
112 	/* Device interface */
113 	CLKNODEMETHOD(clknode_init,		zynqmp_clk_div_init),
114 	CLKNODEMETHOD(clknode_recalc_freq,	zynqmp_clk_div_recalc),
115 	CLKNODEMETHOD(clknode_set_freq,		zynqmp_clk_div_set_freq),
116 	CLKNODEMETHOD_END
117 };
118 
119 DEFINE_CLASS_1(zynqmp_clk_div_clknode, zynqmp_clk_div_clknode_class,
120     zynqmp_clk_div_clknode_methods, sizeof(struct zynqmp_clk_div_softc), clknode_class);
121 
122 int
123 zynqmp_clk_div_register(struct clkdom *clkdom, device_t fw, struct clknode_init_def *clkdef, enum zynqmp_clk_div_type type)
124 {
125 	struct clknode *clk;
126 	struct zynqmp_clk_div_softc *sc;
127 	uint32_t fw_clk_id;
128 
129 	fw_clk_id = clkdef->id - 1;
130 	clkdef->id = 0;
131 	clk = clknode_create(clkdom, &zynqmp_clk_div_clknode_class, clkdef);
132 	if (clk == NULL)
133 		return (1);
134 	sc = clknode_get_softc(clk);
135 	sc->id = fw_clk_id;
136 	sc->firmware = fw;
137 	sc->type = type;
138 	clknode_register(clkdom, clk);
139 	return (0);
140 }
141