xref: /openbsd-src/sys/dev/fdt/bcm2711_tmon.c (revision 471aeecfc619bc9b69519928152daf993376c2a1)
1 /*
2  * Copyright (c) 2020 Alastair Poole <netstar@gmail.com>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <sys/param.h>
18 #include <sys/systm.h>
19 #include <sys/device.h>
20 #include <sys/sensors.h>
21 
22 #include <machine/bus.h>
23 #include <machine/fdt.h>
24 
25 #include <dev/ofw/openfirm.h>
26 #include <dev/ofw/fdt.h>
27 
28 /* Registers */
29 #define  BCMTMON_TSENSSTAT		0x200
30 #define  BCMTMON_TSENSSTAT_VALID	(1 << 10)
31 #define  BCMTMON_TSENSSTAT_DATA(x)	((x) & 0x3ff)
32 
33 #define HREAD4(sc, reg)	\
34 	(bus_space_read_4((sc)->sc_iot, (sc)->sc_ioh, (reg)))
35 
36 struct bcmtmon_softc {
37 	struct device		sc_dev;
38 	bus_space_tag_t		sc_iot;
39 	bus_space_handle_t	sc_ioh;
40 	bus_size_t		sc_tsensstat;
41 
42 	int32_t			sc_slope;
43 	int32_t			sc_offset;
44 
45 	struct ksensor		sc_sensor;
46 	struct ksensordev	sc_sensordev;
47 };
48 
49 int	bcmtmon_match(struct device *, void *, void *);
50 void	bcmtmon_attach(struct device *, struct device *, void *);
51 
52 const struct cfattach bcmtmon_ca = {
53 	sizeof (struct bcmtmon_softc), bcmtmon_match, bcmtmon_attach
54 };
55 
56 struct cfdriver bcmtmon_cd = {
57 	NULL, "bcmtmon", DV_DULL
58 };
59 
60 void	bcmtmon_refresh_sensors(void *);
61 
62 int
bcmtmon_match(struct device * parent,void * match,void * aux)63 bcmtmon_match(struct device *parent, void *match, void *aux)
64 {
65 	struct fdt_attach_args *faa = aux;
66 
67 	if (OF_is_compatible(faa->fa_node, "brcm,bcm2711-avs-monitor") ||
68 	    OF_is_compatible(faa->fa_node, "brcm,avs-tmon-bcm2711") ||
69 	    OF_is_compatible(faa->fa_node, "brcm,avs-tmon-bcm2838"))
70 		return 10;	/* Must beat syscon(4). */
71 
72 	return 0;
73 }
74 
75 void
bcmtmon_attach(struct device * parent,struct device * self,void * aux)76 bcmtmon_attach(struct device *parent, struct device *self, void *aux)
77 {
78 	struct bcmtmon_softc *sc = (struct bcmtmon_softc *)self;
79 	struct fdt_attach_args *faa = aux;
80 
81 	if (faa->fa_nreg < 1) {
82 		printf(": no registers\n");
83 		return;
84 	}
85 
86 	sc->sc_iot = faa->fa_iot;
87 
88 	if (bus_space_map(sc->sc_iot, faa->fa_reg[0].addr,
89 	    faa->fa_reg[0].size, 0, &sc->sc_ioh)) {
90 		printf(": can't map registers\n");
91 		return;
92 	}
93 
94 	printf("\n");
95 
96 	if (OF_is_compatible(faa->fa_node, "brcm,bcm2711-avs-monitor"))
97 		sc->sc_tsensstat = BCMTMON_TSENSSTAT;
98 
99 	sc->sc_slope = -487;
100 	sc->sc_offset = 410040;
101 
102 	/* Register sensors. */
103 	strlcpy(sc->sc_sensordev.xname, sc->sc_dev.dv_xname,
104 	    sizeof(sc->sc_sensordev.xname));
105 	sc->sc_sensor.type = SENSOR_TEMP;
106 	sc->sc_sensor.flags = SENSOR_FINVALID;
107 	sensor_attach(&sc->sc_sensordev, &sc->sc_sensor);
108 	sensordev_install(&sc->sc_sensordev);
109 	sensor_task_register(sc, bcmtmon_refresh_sensors, 5);
110 }
111 
112 void
bcmtmon_refresh_sensors(void * arg)113 bcmtmon_refresh_sensors(void *arg)
114 {
115 	struct bcmtmon_softc *sc = arg;
116 	int32_t code, temp;
117 
118 	code = HREAD4(sc, sc->sc_tsensstat);
119 	temp = sc->sc_slope * BCMTMON_TSENSSTAT_DATA(code) + sc->sc_offset;
120 
121 	sc->sc_sensor.value = 273150000 + 1000 * temp;
122 
123 	if (code & BCMTMON_TSENSSTAT_VALID)
124 		sc->sc_sensor.flags &= ~SENSOR_FINVALID;
125 	else
126 		sc->sc_sensor.flags |= SENSOR_FINVALID;
127 }
128