1 /* $OpenBSD: qcmtx.c,v 1.1 2023/05/17 23:30:58 patrick Exp $ */
2 /*
3 * Copyright (c) 2023 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 <sys/malloc.h>
22
23 #include <machine/bus.h>
24 #include <machine/fdt.h>
25
26 #include <dev/ofw/openfirm.h>
27 #include <dev/ofw/ofw_misc.h>
28 #include <dev/ofw/fdt.h>
29
30 #define QCMTX_OFF(idx) ((idx) * 0x1000)
31 #define QCMTX_NUM_LOCKS 32
32 #define QCMTX_APPS_PROC_ID 1
33
34 #define HREAD4(sc, reg) \
35 (bus_space_read_4((sc)->sc_iot, (sc)->sc_ioh, (reg)))
36 #define HWRITE4(sc, reg, val) \
37 bus_space_write_4((sc)->sc_iot, (sc)->sc_ioh, (reg), (val))
38
39 struct qcmtx_softc {
40 struct device sc_dev;
41 bus_space_tag_t sc_iot;
42 bus_space_handle_t sc_ioh;
43 int sc_node;
44
45 struct hwlock_device sc_hd;
46 };
47
48 int qcmtx_match(struct device *, void *, void *);
49 void qcmtx_attach(struct device *, struct device *, void *);
50
51 int qcmtx_lock(void *, uint32_t *, int);
52
53 const struct cfattach qcmtx_ca = {
54 sizeof (struct qcmtx_softc), qcmtx_match, qcmtx_attach
55 };
56
57 struct cfdriver qcmtx_cd = {
58 NULL, "qcmtx", DV_DULL
59 };
60
61 int
qcmtx_match(struct device * parent,void * match,void * aux)62 qcmtx_match(struct device *parent, void *match, void *aux)
63 {
64 struct fdt_attach_args *faa = aux;
65
66 return OF_is_compatible(faa->fa_node, "qcom,tcsr-mutex");
67 }
68
69 void
qcmtx_attach(struct device * parent,struct device * self,void * aux)70 qcmtx_attach(struct device *parent, struct device *self, void *aux)
71 {
72 struct qcmtx_softc *sc = (struct qcmtx_softc *)self;
73 struct fdt_attach_args *faa = aux;
74
75 if (faa->fa_nreg < 1) {
76 printf(": no registers\n");
77 return;
78 }
79
80 sc->sc_node = faa->fa_node;
81 sc->sc_iot = faa->fa_iot;
82 if (bus_space_map(sc->sc_iot, faa->fa_reg[0].addr,
83 faa->fa_reg[0].size, 0, &sc->sc_ioh)) {
84 printf(": can't map registers\n");
85 return;
86 }
87
88 printf("\n");
89
90 sc->sc_hd.hd_node = faa->fa_node;
91 sc->sc_hd.hd_cookie = sc;
92 sc->sc_hd.hd_lock = qcmtx_lock;
93 hwlock_register(&sc->sc_hd);
94 }
95
96 int
qcmtx_lock(void * cookie,uint32_t * cells,int lock)97 qcmtx_lock(void *cookie, uint32_t *cells, int lock)
98 {
99 struct qcmtx_softc *sc = cookie;
100 int idx = cells[0];
101
102 if (idx >= QCMTX_NUM_LOCKS)
103 return ENXIO;
104
105 if (lock) {
106 HWRITE4(sc, QCMTX_OFF(idx), QCMTX_APPS_PROC_ID);
107 if (HREAD4(sc, QCMTX_OFF(idx)) !=
108 QCMTX_APPS_PROC_ID)
109 return EAGAIN;
110 KASSERT(HREAD4(sc, QCMTX_OFF(idx)) == QCMTX_APPS_PROC_ID);
111 } else {
112 KASSERT(HREAD4(sc, QCMTX_OFF(idx)) == QCMTX_APPS_PROC_ID);
113 HWRITE4(sc, QCMTX_OFF(idx), 0);
114 }
115
116 return 0;
117 }
118