freebsd-skq/sys/arm/mv/mv_ts.c
loos f73b4006ff Fix the deciKelvin to Celsius conversion in kernel.
After r285994, sysctl(8) was fixed to use 273.15 instead of 273.20 as 0C
reference and as result, the temperature read in sysctl(8) now exibits a
+0.1C difference.

This commit fix the kernel references to match the reference value used in
sysctl(8) after r285994.

Sponsored by:	Rubicon Communications (Netgate)
2016-05-22 13:58:32 +00:00

181 lines
4.6 KiB
C

/*-
* Copyright (c) 2012 Hiroki Sato <hrs@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* Driver for on-die thermal sensor in 88F6282 and 88F6283.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/bus.h>
#include <sys/sysctl.h>
#include <dev/fdt/fdt_common.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <arm/mv/mvreg.h>
#include <arm/mv/mvvar.h>
static struct resource_spec mvts_res[] = {
{ SYS_RES_MEMORY, 0, RF_ACTIVE },
{ -1, 0 }
};
struct mvts_softc {
device_t sc_dev;
struct resource *sc_res[sizeof(mvts_res)];
};
static int
ts_probe(device_t dev)
{
uint32_t d, r;
if (!ofw_bus_status_okay(dev))
return (ENXIO);
if (!ofw_bus_is_compatible(dev, "mrvl,ts"))
return (ENXIO);
soc_id(&d, &r);
switch (d) {
case MV_DEV_88F6282:
break;
default:
device_printf(dev, "unsupported SoC (ID: 0x%08X)!\n", d);
return (ENXIO);
}
device_set_desc(dev, "Marvell Thermal Sensor");
return (0);
}
#define MV_TEMP_VALID_BIT (1 << 9)
#define MV_TEMP_SENS_OFFS 10
#define MV_TEMP_SENS_MASK 0x1ff
#define MV_TEMP_SENS_READ_MAX 16
#define TZ_ZEROC 2731
#define MV_TEMP_CONVERT(x) ((((322 - x) * 100000) / 13625) + TZ_ZEROC)
/*
* MSB LSB
* 0000 0000 0000 0000 0000 0000 0000 0000
* ^- valid bit
* |---------|
* ^--- temperature (9 bits)
*/
static int
ts_sysctl_handler(SYSCTL_HANDLER_ARGS)
{
struct mvts_softc *sc;
device_t dev;
uint32_t ret, ret0;
u_int val;
int i;
dev = (device_t)arg1;
sc = device_get_softc(dev);
val = TZ_ZEROC;
ret = bus_read_4(sc->sc_res[0], 0);
if ((ret & MV_TEMP_VALID_BIT) == 0) {
device_printf(dev, "temperature sensor is broken.\n");
goto ts_sysctl_handle_int;
}
ret0 = 0;
for (i = 0; i < MV_TEMP_SENS_READ_MAX; i++) {
ret = bus_read_4(sc->sc_res[0], 0);
ret = (ret >> MV_TEMP_SENS_OFFS) & MV_TEMP_SENS_MASK;
/*
* Successive reads should returns the same value except
* for the LSB when the sensor is normal.
*/
if (((ret0 ^ ret) & 0x1fe) == 0)
break;
else
ret0 = ret;
}
if (i == MV_TEMP_SENS_READ_MAX) {
device_printf(dev, "temperature sensor is unstable.\n");
goto ts_sysctl_handle_int;
}
val = (u_int)MV_TEMP_CONVERT(ret);
ts_sysctl_handle_int:
return (sysctl_handle_int(oidp, &val, 0, req));
}
static int
ts_attach(device_t dev)
{
struct mvts_softc *sc;
struct sysctl_ctx_list *ctx;
int error;
sc = device_get_softc(dev);
sc->sc_dev = dev;
error = bus_alloc_resources(dev, mvts_res, sc->sc_res);
if (error) {
device_printf(dev, "could not allocate resources\n");
return (ENXIO);
}
ctx = device_get_sysctl_ctx(dev);
SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
OID_AUTO, "temperature", CTLTYPE_INT | CTLFLAG_RD, dev,
0, ts_sysctl_handler, "IK", "Current Temperature");
return (0);
}
static int
ts_detach(device_t dev)
{
return (0);
}
static device_method_t ts_methods[] = {
DEVMETHOD(device_probe, ts_probe),
DEVMETHOD(device_attach, ts_attach),
DEVMETHOD(device_detach, ts_detach),
{0, 0},
};
static driver_t ts_driver = {
"mvts",
ts_methods,
sizeof(struct mvts_softc),
};
static devclass_t ts_devclass;
DRIVER_MODULE(mvts, simplebus, ts_driver, ts_devclass, 0, 0);
MODULE_VERSION(mvts, 1);