xref: /freebsd/sys/arm/mv/clk/a37x0_xtal.c (revision e0c4386e)
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/kernel.h>
31 #include <sys/module.h>
32 #include <sys/mutex.h>
33 #include <sys/rman.h>
34 #include <machine/bus.h>
35 
36 #include <dev/fdt/simplebus.h>
37 
38 #include <dev/clk/clk.h>
39 #include <dev/clk/clk_fixed.h>
40 #include <dev/syscon/syscon.h>
41 
42 #include <dev/ofw/ofw_bus.h>
43 #include <dev/ofw/ofw_bus_subr.h>
44 
45 #include "syscon_if.h"
46 
47 #define BIT(x)			(1 << (x))
48 
49 #define NB_GPIO1_PIN_LT_L	0x8
50 #define NB_GPIO1_MPP1_9		BIT(9)
51 
52 struct a37x0_xtal_softc {
53 	device_t 		dev;
54 	struct clkdom		*clkdom;
55 };
56 
57 static int a37x0_xtal_attach(device_t dev);
58 static int a37x0_xtal_detach(device_t dev);
59 static int a37x0_xtal_probe(device_t dev);
60 
61 static device_method_t a37x0_xtal_methods [] = {
62 	DEVMETHOD(device_probe, 	a37x0_xtal_probe),
63 	DEVMETHOD(device_attach, 	a37x0_xtal_attach),
64 	DEVMETHOD(device_detach, 	a37x0_xtal_detach),
65 	DEVMETHOD_END
66 };
67 
68 static driver_t a37x0_xtal_driver = {
69 	"a37x0-xtal",
70 	a37x0_xtal_methods,
71 	sizeof(struct a37x0_xtal_softc)
72 };
73 
74 EARLY_DRIVER_MODULE(a37x0_xtal, simplebus, a37x0_xtal_driver, 0, 0,
75     BUS_PASS_TIMER + BUS_PASS_ORDER_EARLY);
76 
77 static int
78 a37x0_xtal_attach(device_t dev)
79 {
80 	struct a37x0_xtal_softc *sc;
81 	struct clk_fixed_def def;
82 	struct syscon *syscon;
83 	uint32_t reg;
84 	int error;
85 
86 	sc = device_get_softc(dev);
87 
88 	def.clkdef.name = "armada-3700-xtal";
89 	def.clkdef.parent_names = NULL;
90 	def.clkdef.parent_cnt = 0;
91 	def.clkdef.id = 1;
92 	def.mult = 0;
93 	def.div = 0;
94 
95 	if (SYSCON_GET_HANDLE(dev, &syscon) != 0 || syscon == NULL){
96 		device_printf(dev, "Cannot get syscon driver handle\n");
97 		return (ENXIO);
98 	}
99 
100 	reg = SYSCON_READ_4(syscon, NB_GPIO1_PIN_LT_L);
101 	if (reg & NB_GPIO1_MPP1_9)
102 		def.freq = 40000000;
103 	else
104 		def.freq = 25000000;
105 
106 	sc->clkdom = clkdom_create(dev);
107 	error = clknode_fixed_register(sc->clkdom, &def);
108 	if (error){
109 		device_printf(dev, "Cannot register clock node\n");
110 		return (ENXIO);
111 	}
112 
113 	error = clkdom_finit(sc->clkdom);
114 	if (error){
115 		device_printf(dev, "Cannot finalize clock domain initialization\n");
116 		return (ENXIO);
117 	}
118 
119 	if (bootverbose)
120 		clkdom_dump(sc->clkdom);
121 
122 	return (0);
123 }
124 
125 static int
126 a37x0_xtal_probe(device_t dev)
127 {
128 
129 	if (!ofw_bus_status_okay(dev))
130 		return (ENXIO);
131 
132 	if (!ofw_bus_is_compatible(dev, "marvell,armada-3700-xtal-clock"))
133 		return (ENXIO);
134 
135 	device_set_desc(dev, "Marvell Armada 3700 Oscillator");
136 	return (BUS_PROBE_DEFAULT);
137 }
138 
139 static int
140 a37x0_xtal_detach(device_t dev)
141 {
142 
143 	return (EBUSY);
144 }
145