xref: /freebsd/sys/dev/clk/allwinner/aw_ccu.c (revision 1edb7116)
1 /*-
2  * Copyright (c) 2016 Jared McNeill <jmcneill@invisible.ca>
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
17  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
18  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
19  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
20  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
21  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  */
25 
26 /*
27  * Allwinner oscillator clock
28  */
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 #include <sys/rman.h>
34 #include <sys/kernel.h>
35 #include <sys/lock.h>
36 #include <sys/module.h>
37 #include <sys/mutex.h>
38 #include <machine/bus.h>
39 
40 #include <dev/fdt/simplebus.h>
41 
42 #include <dev/ofw/ofw_bus.h>
43 #include <dev/ofw/ofw_bus_subr.h>
44 
45 #include <dev/clk/clk.h>
46 
47 #include "clkdev_if.h"
48 
49 #define	CCU_BASE	0x01c20000
50 #define	CCU_SIZE	0x400
51 
52 struct aw_ccu_softc {
53 	struct simplebus_softc	sc;
54 	bus_space_tag_t		bst;
55 	bus_space_handle_t	bsh;
56 	struct mtx		mtx;
57 	int			flags;
58 };
59 
60 static struct ofw_compat_data compat_data[] = {
61 	{ "allwinner,sun7i-a20",	1 },
62 	{ "allwinner,sun6i-a31",	1 },
63 	{ "allwinner,sun6i-a31s",	1 },
64 	{ NULL, 0 }
65 };
66 
67 static int
68 aw_ccu_check_addr(struct aw_ccu_softc *sc, bus_addr_t addr,
69     bus_space_handle_t *pbsh, bus_size_t *poff)
70 {
71 	if (addr >= CCU_BASE && addr < (CCU_BASE + CCU_SIZE)) {
72 		*poff = addr - CCU_BASE;
73 		*pbsh = sc->bsh;
74 		return (0);
75 	}
76 	return (EINVAL);
77 }
78 
79 static int
80 aw_ccu_write_4(device_t dev, bus_addr_t addr, uint32_t val)
81 {
82 	struct aw_ccu_softc *sc;
83 	bus_space_handle_t bsh;
84 	bus_size_t reg;
85 
86 	sc = device_get_softc(dev);
87 
88 	if (aw_ccu_check_addr(sc, addr, &bsh, &reg) != 0)
89 		return (EINVAL);
90 
91 	mtx_assert(&sc->mtx, MA_OWNED);
92 	bus_space_write_4(sc->bst, bsh, reg, val);
93 
94 	return (0);
95 }
96 
97 static int
98 aw_ccu_read_4(device_t dev, bus_addr_t addr, uint32_t *val)
99 {
100 	struct aw_ccu_softc *sc;
101 	bus_space_handle_t bsh;
102 	bus_size_t reg;
103 
104 	sc = device_get_softc(dev);
105 
106 	if (aw_ccu_check_addr(sc, addr, &bsh, &reg) != 0)
107 		return (EINVAL);
108 
109 	mtx_assert(&sc->mtx, MA_OWNED);
110 	*val = bus_space_read_4(sc->bst, bsh, reg);
111 
112 	return (0);
113 }
114 
115 static int
116 aw_ccu_modify_4(device_t dev, bus_addr_t addr, uint32_t clr, uint32_t set)
117 {
118 	struct aw_ccu_softc *sc;
119 	bus_space_handle_t bsh;
120 	bus_size_t reg;
121 	uint32_t val;
122 
123 	sc = device_get_softc(dev);
124 
125 	if (aw_ccu_check_addr(sc, addr, &bsh, &reg) != 0)
126 		return (EINVAL);
127 
128 	mtx_assert(&sc->mtx, MA_OWNED);
129 	val = bus_space_read_4(sc->bst, bsh, reg);
130 	val &= ~clr;
131 	val |= set;
132 	bus_space_write_4(sc->bst, bsh, reg, val);
133 
134 	return (0);
135 }
136 
137 static void
138 aw_ccu_device_lock(device_t dev)
139 {
140 	struct aw_ccu_softc *sc;
141 
142 	sc = device_get_softc(dev);
143 	mtx_lock(&sc->mtx);
144 }
145 
146 static void
147 aw_ccu_device_unlock(device_t dev)
148 {
149 	struct aw_ccu_softc *sc;
150 
151 	sc = device_get_softc(dev);
152 	mtx_unlock(&sc->mtx);
153 }
154 
155 static const struct ofw_compat_data *
156 aw_ccu_search_compatible(void)
157 {
158 	const struct ofw_compat_data *compat;
159 	phandle_t root;
160 
161 	root = OF_finddevice("/");
162 	for (compat = compat_data; compat->ocd_str != NULL; compat++)
163 		if (ofw_bus_node_is_compatible(root, compat->ocd_str))
164 			break;
165 
166 	return (compat);
167 }
168 
169 static int
170 aw_ccu_probe(device_t dev)
171 {
172 	const char *name;
173 
174 	name = ofw_bus_get_name(dev);
175 
176 	if (name == NULL || strcmp(name, "clocks") != 0)
177 		return (ENXIO);
178 
179 	if (aw_ccu_search_compatible()->ocd_data == 0)
180 		return (ENXIO);
181 
182 	device_set_desc(dev, "Allwinner Clock Control Unit");
183 	return (BUS_PROBE_SPECIFIC);
184 }
185 
186 static int
187 aw_ccu_attach(device_t dev)
188 {
189 	struct aw_ccu_softc *sc;
190 	phandle_t node, child;
191 	device_t cdev;
192 	int error;
193 
194 	sc = device_get_softc(dev);
195 	node = ofw_bus_get_node(dev);
196 
197 	simplebus_init(dev, node);
198 
199 	sc->flags = aw_ccu_search_compatible()->ocd_data;
200 
201 	/*
202 	 * Map registers. The DT doesn't have a "reg" property
203 	 * for the /clocks node and child nodes have conflicting "reg"
204 	 * properties.
205 	 */
206 	sc->bst = bus_get_bus_tag(dev);
207 	error = bus_space_map(sc->bst, CCU_BASE, CCU_SIZE, 0,
208 	    &sc->bsh);
209 	if (error != 0) {
210 		device_printf(dev, "couldn't map CCU: %d\n", error);
211 		return (error);
212 	}
213 
214 	mtx_init(&sc->mtx, device_get_nameunit(dev), NULL, MTX_DEF);
215 
216 	/* Attach child devices */
217 	for (child = OF_child(node); child > 0; child = OF_peer(child)) {
218 		cdev = simplebus_add_device(dev, child, 0, NULL, -1, NULL);
219 		if (cdev != NULL)
220 			device_probe_and_attach(cdev);
221 	}
222 
223 	return (bus_generic_attach(dev));
224 }
225 
226 static device_method_t aw_ccu_methods[] = {
227 	/* Device interface */
228 	DEVMETHOD(device_probe,		aw_ccu_probe),
229 	DEVMETHOD(device_attach,	aw_ccu_attach),
230 
231 	/* clkdev interface */
232 	DEVMETHOD(clkdev_write_4,	aw_ccu_write_4),
233 	DEVMETHOD(clkdev_read_4,	aw_ccu_read_4),
234 	DEVMETHOD(clkdev_modify_4,	aw_ccu_modify_4),
235 	DEVMETHOD(clkdev_device_lock,	aw_ccu_device_lock),
236 	DEVMETHOD(clkdev_device_unlock,	aw_ccu_device_unlock),
237 
238 	DEVMETHOD_END
239 };
240 
241 DEFINE_CLASS_1(aw_ccu, aw_ccu_driver, aw_ccu_methods,
242     sizeof(struct aw_ccu_softc), simplebus_driver);
243 
244 EARLY_DRIVER_MODULE(aw_ccu, simplebus, aw_ccu_driver, 0, 0,
245     BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
246 
247 MODULE_VERSION(aw_ccu, 1);
248