From 63b2d7c5bf2a5c0bd85480c61494d6560741ebb9 Mon Sep 17 00:00:00 2001 From: kettenis Date: Sat, 24 Feb 2018 11:06:59 +0000 Subject: [PATCH] Add bcmtemp(4), a driver for the temperature sensor on the Raspberry Pi. --- sys/dev/fdt/bcm2835_temp.c | 124 +++++++++++++++++++++++++++++++++++++ sys/dev/fdt/files.fdt | 6 +- 2 files changed, 129 insertions(+), 1 deletion(-) create mode 100644 sys/dev/fdt/bcm2835_temp.c diff --git a/sys/dev/fdt/bcm2835_temp.c b/sys/dev/fdt/bcm2835_temp.c new file mode 100644 index 00000000000..c5aab990656 --- /dev/null +++ b/sys/dev/fdt/bcm2835_temp.c @@ -0,0 +1,124 @@ +/* $OpenBSD: bcm2835_temp.c,v 1.1 2018/02/24 11:06:59 kettenis Exp $ */ +/* + * Copyright (c) 2018 Mark Kettenis + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#include +#include +#include +#include + +#include +#include + +#include +#include + +/* Registers */ +#define TS_TSENSCTL 0x0000 +#define TS_TSENSSTAT 0x0004 +#define TS_TSENSSTAT_VALID (1 << 10) +#define TS_TSENSSTAT_DATA(x) ((x) & 0x3ff) + +#define HREAD4(sc, reg) \ + (bus_space_read_4((sc)->sc_iot, (sc)->sc_ioh, (reg))) +#define HWRITE4(sc, reg, val) \ + bus_space_write_4((sc)->sc_iot, (sc)->sc_ioh, (reg), (val)) + +struct bcmtemp_softc { + struct device sc_dev; + bus_space_tag_t sc_iot; + bus_space_handle_t sc_ioh; + + int32_t sc_slope; + int32_t sc_offset; + + struct ksensor sc_sensor; + struct ksensordev sc_sensordev; +}; + +int bcmtemp_match(struct device *, void *, void *); +void bcmtemp_attach(struct device *, struct device *, void *); + +struct cfattach bcmtemp_ca = { + sizeof (struct bcmtemp_softc), bcmtemp_match, bcmtemp_attach +}; + +struct cfdriver bcmtemp_cd = { + NULL, "bcmtemp", DV_DULL +}; + +void bcmtemp_refresh_sensors(void *); + +int +bcmtemp_match(struct device *parent, void *match, void *aux) +{ + struct fdt_attach_args *faa = aux; + + return (OF_is_compatible(faa->fa_node, "brcm,bcm2836-thermal") || + OF_is_compatible(faa->fa_node, "brcm,bcm2837-thermal")); +} + +void +bcmtemp_attach(struct device *parent, struct device *self, void *aux) +{ + struct bcmtemp_softc *sc = (struct bcmtemp_softc *)self; + struct fdt_attach_args *faa = aux; + + if (faa->fa_nreg < 1) { + printf(": no registers\n"); + return; + } + + sc->sc_iot = faa->fa_iot; + if (bus_space_map(sc->sc_iot, faa->fa_reg[0].addr, + faa->fa_reg[0].size, 0, &sc->sc_ioh)) { + printf(": can't map registers\n"); + return; + } + + printf("\n"); + + /* XXX fetch these from /thermal-zones. */ + sc->sc_slope = -538; + if (OF_is_compatible(faa->fa_node, "brcm,bcm2836-thermal")) + sc->sc_offset = 407000; + else + sc->sc_offset = 412000; + + /* Register sensors. */ + strlcpy(sc->sc_sensordev.xname, sc->sc_dev.dv_xname, + sizeof(sc->sc_sensordev.xname)); + sc->sc_sensor.type = SENSOR_TEMP; + sc->sc_sensor.flags = SENSOR_FINVALID; + sensor_attach(&sc->sc_sensordev, &sc->sc_sensor); + sensordev_install(&sc->sc_sensordev); + sensor_task_register(sc, bcmtemp_refresh_sensors, 5); +} + +void +bcmtemp_refresh_sensors(void *arg) +{ + struct bcmtemp_softc *sc = arg; + int32_t code, temp; + + code = HREAD4(sc, TS_TSENSSTAT); + temp = sc->sc_offset + TS_TSENSSTAT_DATA(code) * sc->sc_slope; + sc->sc_sensor.value = 273150000 + 1000 * temp; + if (code & TS_TSENSSTAT_VALID) + sc->sc_sensor.flags &= ~SENSOR_FINVALID; + else + sc->sc_sensor.flags |= SENSOR_FINVALID; +} diff --git a/sys/dev/fdt/files.fdt b/sys/dev/fdt/files.fdt index 65286f96bd3..d5d71a7dd31 100644 --- a/sys/dev/fdt/files.fdt +++ b/sys/dev/fdt/files.fdt @@ -1,4 +1,4 @@ -# $OpenBSD: files.fdt,v 1.37 2018/01/17 10:17:33 kettenis Exp $ +# $OpenBSD: files.fdt,v 1.38 2018/02/24 11:06:59 kettenis Exp $ # # Config file and device description for machine-independent FDT code. # Included by ports that need it. @@ -57,6 +57,10 @@ device bcmdog attach bcmdog at fdt file dev/fdt/bcm2835_dog.c bcmdog +device bcmtemp +attach bcmtemp at fdt +file dev/fdt/bcm2835_temp.c bcmdog + device exrtc attach exrtc at fdt file dev/fdt/exrtc.c exrtc -- 2.20.1