xref: /freebsd/sys/arm/annapurna/alpine/alpine_ccu.c (revision fdafd315ad0d0f28a11b9fb4476a9ab059c62b92)
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/param.h>
30 #include <sys/bus.h>
31 #include <sys/conf.h>
32 #include <sys/rman.h>
33 #include <sys/kernel.h>
34 #include <sys/module.h>
35 #include <sys/resource.h>
36 #include <sys/systm.h>
37 
38 #include <machine/bus.h>
39 #include <dev/ofw/ofw_bus_subr.h>
40 
41 #define	AL_CCU_SNOOP_CONTROL_IOFAB_0_OFFSET	0x4000
42 #define	AL_CCU_SNOOP_CONTROL_IOFAB_1_OFFSET	0x5000
43 #define	AL_CCU_SPECULATION_CONTROL_OFFSET	0x4
44 
45 static struct resource_spec al_ccu_spec[] = {
46 	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },
47 	{ -1, 0 }
48 };
49 
50 struct al_ccu_softc {
51 	struct resource	*res;
52 };
53 
54 static int al_ccu_probe(device_t dev);
55 static int al_ccu_attach(device_t dev);
56 static int al_ccu_detach(device_t dev);
57 
58 static device_method_t al_ccu_methods[] = {
59 	DEVMETHOD(device_probe,		al_ccu_probe),
60 	DEVMETHOD(device_attach,	al_ccu_attach),
61 	DEVMETHOD(device_detach,	al_ccu_detach),
62 	{ 0, 0 }
63 };
64 
65 static driver_t al_ccu_driver = {
66 	"ccu",
67 	al_ccu_methods,
68 	sizeof(struct al_ccu_softc)
69 };
70 
71 EARLY_DRIVER_MODULE(al_ccu, simplebus, al_ccu_driver, 0, 0,
72     BUS_PASS_CPU + BUS_PASS_ORDER_MIDDLE);
73 EARLY_DRIVER_MODULE(al_ccu, ofwbus, al_ccu_driver, 0, 0,
74     BUS_PASS_CPU + BUS_PASS_ORDER_MIDDLE);
75 
76 static int
al_ccu_probe(device_t dev)77 al_ccu_probe(device_t dev)
78 {
79 
80 	if (!ofw_bus_status_okay(dev))
81 		return (ENXIO);
82 
83 	if (!ofw_bus_is_compatible(dev, "annapurna-labs,al-ccu"))
84 		return (ENXIO);
85 
86 	device_set_desc(dev, "Alpine CCU");
87 
88 	return (BUS_PROBE_DEFAULT);
89 }
90 
91 static int
al_ccu_attach(device_t dev)92 al_ccu_attach(device_t dev)
93 {
94 	struct al_ccu_softc *sc;
95 	int err;
96 
97 	sc = device_get_softc(dev);
98 
99 	err = bus_alloc_resources(dev, al_ccu_spec, &sc->res);
100 	if (err != 0) {
101 		device_printf(dev, "could not allocate resources\n");
102 		return (err);
103 	}
104 
105 	/* Enable cache snoop */
106 	bus_write_4(sc->res, AL_CCU_SNOOP_CONTROL_IOFAB_0_OFFSET, 1);
107 	bus_write_4(sc->res, AL_CCU_SNOOP_CONTROL_IOFAB_1_OFFSET, 1);
108 
109 	/* Disable speculative fetches from masters */
110 	bus_write_4(sc->res, AL_CCU_SPECULATION_CONTROL_OFFSET, 7);
111 
112 	return (0);
113 }
114 
115 static int
al_ccu_detach(device_t dev)116 al_ccu_detach(device_t dev)
117 {
118 	struct al_ccu_softc *sc;
119 
120 	sc = device_get_softc(dev);
121 
122 	bus_release_resources(dev, al_ccu_spec, &sc->res);
123 
124 	return (0);
125 }
126