1 /* $OpenBSD: mvagc.c,v 1.2 2021/10/24 17:52:27 mpi Exp $ */
2 /*
3 * Copyright (c) 2016 Patrick Wildt <patrick@blueri.se>
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18 #include <sys/param.h>
19 #include <sys/systm.h>
20 #include <sys/device.h>
21 #include <machine/bus.h>
22 #include <machine/fdt.h>
23
24 #include <dev/ofw/openfirm.h>
25 #include <dev/ofw/ofw_clock.h>
26 #include <dev/ofw/fdt.h>
27
28 #define HREAD4(sc, reg) \
29 (bus_space_read_4((sc)->sc_iot, (sc)->sc_ioh, (reg)))
30 #define HWRITE4(sc, reg, val) \
31 bus_space_write_4((sc)->sc_iot, (sc)->sc_ioh, (reg), (val))
32 #define HSET4(sc, reg, bits) \
33 HWRITE4((sc), (reg), HREAD4((sc), (reg)) | (bits))
34 #define HCLR4(sc, reg, bits) \
35 HWRITE4((sc), (reg), HREAD4((sc), (reg)) & ~(bits))
36
37 struct mvagc_softc {
38 struct device sc_dev;
39 bus_space_tag_t sc_iot;
40 bus_space_handle_t sc_ioh;
41 int sc_node;
42 struct clock_device sc_cd;
43 };
44
45 int mvagc_match(struct device *, void *, void *);
46 void mvagc_attach(struct device *, struct device *, void *);
47
48 void mvagc_enable(void *, uint32_t *, int);
49 uint32_t mvagc_gen_get_frequency(void *, uint32_t *);
50
51 const struct cfattach mvagc_ca = {
52 sizeof (struct mvagc_softc), mvagc_match, mvagc_attach
53 };
54
55 struct cfdriver mvagc_cd = {
56 NULL, "mvagc", DV_DULL
57 };
58
59 int
mvagc_match(struct device * parent,void * cfdata,void * aux)60 mvagc_match(struct device *parent, void *cfdata, void *aux)
61 {
62 struct fdt_attach_args *faa = aux;
63
64 return (OF_is_compatible(faa->fa_node,
65 "marvell,armada-380-gating-clock"));
66 }
67
68 void
mvagc_attach(struct device * parent,struct device * self,void * args)69 mvagc_attach(struct device *parent, struct device *self, void *args)
70 {
71 struct mvagc_softc *sc = (struct mvagc_softc *)self;
72 struct fdt_attach_args *faa = args;
73
74 sc->sc_node = faa->fa_node;
75 sc->sc_iot = faa->fa_iot;
76 if (bus_space_map(sc->sc_iot, faa->fa_reg[0].addr,
77 faa->fa_reg[0].size, 0, &sc->sc_ioh))
78 panic("%s: bus_space_map failed!", __func__);
79
80 printf("\n");
81
82 sc->sc_cd.cd_node = sc->sc_node;
83 sc->sc_cd.cd_cookie = sc;
84 sc->sc_cd.cd_get_frequency = mvagc_gen_get_frequency;
85 sc->sc_cd.cd_enable = mvagc_enable;
86 clock_register(&sc->sc_cd);
87 }
88
89 /*
90 * A "generic" function that simply gets the clock frequency from the
91 * parent clock. Useful for clock gating devices that don't scale
92 * their clocks.
93 */
94 uint32_t
mvagc_gen_get_frequency(void * cookie,uint32_t * cells)95 mvagc_gen_get_frequency(void *cookie, uint32_t *cells)
96 {
97 struct mvagc_softc *sc = cookie;
98
99 return clock_get_frequency(sc->sc_node, NULL);
100 }
101
102 void
mvagc_enable(void * cookie,uint32_t * cells,int on)103 mvagc_enable(void *cookie, uint32_t *cells, int on)
104 {
105 struct mvagc_softc *sc = cookie;
106 uint32_t id = cells[0];
107
108 if (id >= 32)
109 return;
110
111 if (on)
112 HSET4(sc, 0, (1 << id));
113 else
114 HCLR4(sc, 0, (1 << id));
115 }
116