xref: /freebsd/sys/arm/annapurna/alpine/alpine_ccu.c (revision 401ab69cff8fa2320a9f8ea4baa114a6da6c952b)
1 /*-
2  * Copyright (c) 2015,2016 Annapurna Labs Ltd. and affiliates
3  * All rights reserved.
4  *
5  * Developed by Semihalf.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 #include <sys/param.h>
31 #include <sys/bus.h>
32 #include <sys/conf.h>
33 #include <sys/rman.h>
34 #include <sys/kernel.h>
35 #include <sys/module.h>
36 #include <sys/resource.h>
37 #include <sys/systm.h>
38 
39 #include <machine/bus.h>
40 #include <dev/ofw/ofw_bus_subr.h>
41 
42 #define	AL_CCU_SNOOP_CONTROL_IOFAB_0_OFFSET	0x4000
43 #define	AL_CCU_SNOOP_CONTROL_IOFAB_1_OFFSET	0x5000
44 #define	AL_CCU_SPECULATION_CONTROL_OFFSET	0x4
45 
46 static struct resource_spec al_ccu_spec[] = {
47 	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },
48 	{ -1, 0 }
49 };
50 
51 struct al_ccu_softc {
52 	struct resource	*res;
53 };
54 
55 static int al_ccu_probe(device_t dev);
56 static int al_ccu_attach(device_t dev);
57 static int al_ccu_detach(device_t dev);
58 
59 static device_method_t al_ccu_methods[] = {
60 	DEVMETHOD(device_probe,		al_ccu_probe),
61 	DEVMETHOD(device_attach,	al_ccu_attach),
62 	DEVMETHOD(device_detach,	al_ccu_detach),
63 	{ 0, 0 }
64 };
65 
66 static driver_t al_ccu_driver = {
67 	"ccu",
68 	al_ccu_methods,
69 	sizeof(struct al_ccu_softc)
70 };
71 
72 EARLY_DRIVER_MODULE(al_ccu, simplebus, al_ccu_driver, 0, 0,
73     BUS_PASS_CPU + BUS_PASS_ORDER_MIDDLE);
74 EARLY_DRIVER_MODULE(al_ccu, ofwbus, al_ccu_driver, 0, 0,
75     BUS_PASS_CPU + BUS_PASS_ORDER_MIDDLE);
76 
77 static int
78 al_ccu_probe(device_t dev)
79 {
80 
81 	if (!ofw_bus_status_okay(dev))
82 		return (ENXIO);
83 
84 	if (!ofw_bus_is_compatible(dev, "annapurna-labs,al-ccu"))
85 		return (ENXIO);
86 
87 	device_set_desc(dev, "Alpine CCU");
88 
89 	return (BUS_PROBE_DEFAULT);
90 }
91 
92 static int
93 al_ccu_attach(device_t dev)
94 {
95 	struct al_ccu_softc *sc;
96 	int err;
97 
98 	sc = device_get_softc(dev);
99 
100 	err = bus_alloc_resources(dev, al_ccu_spec, &sc->res);
101 	if (err != 0) {
102 		device_printf(dev, "could not allocate resources\n");
103 		return (err);
104 	}
105 
106 	/* Enable cache snoop */
107 	bus_write_4(sc->res, AL_CCU_SNOOP_CONTROL_IOFAB_0_OFFSET, 1);
108 	bus_write_4(sc->res, AL_CCU_SNOOP_CONTROL_IOFAB_1_OFFSET, 1);
109 
110 	/* Disable speculative fetches from masters */
111 	bus_write_4(sc->res, AL_CCU_SPECULATION_CONTROL_OFFSET, 7);
112 
113 	return (0);
114 }
115 
116 static int
117 al_ccu_detach(device_t dev)
118 {
119 	struct al_ccu_softc *sc;
120 
121 	sc = device_get_softc(dev);
122 
123 	bus_release_resources(dev, al_ccu_spec, &sc->res);
124 
125 	return (0);
126 }
127