static int
temp_throttle_sysctl_handler(SYSCTL_HANDLER_ARGS)
{
struct imx6_anatop_softc *sc = arg1;
int err;
uint32_t temp;
temp = sc->temp_throttle_val + TZ_ZEROC;
err = sysctl_handle_int(oidp, &temp, 0, req);
if (temp < TZ_ZEROC)
return (ERANGE);
temp -= TZ_ZEROC;
if (err != 0 || req->newptr == NULL || temp == sc->temp_throttle_val)
return (err);
/* Value changed, update counts in softc and hardware. */
sc->temp_throttle_val = temp;
sc->temp_throttle_trigger_cnt = temp_to_count(sc, sc->temp_throttle_val);
sc->temp_throttle_reset_cnt = temp_to_count(sc, sc->temp_throttle_val - 100);
imx6_anatop_write_4(IMX6_ANALOG_TEMPMON_TEMPSENSE0_CLR,
IMX6_ANALOG_TEMPMON_TEMPSENSE0_ALARM_MASK);
imx6_anatop_write_4(IMX6_ANALOG_TEMPMON_TEMPSENSE0_SET,
(sc->temp_throttle_trigger_cnt <<
IMX6_ANALOG_TEMPMON_TEMPSENSE0_ALARM_SHIFT));
return (err);
}
static void
initialize_tempmon(struct imx6_anatop_softc *sc)
{
uint32_t cal;
struct sysctl_ctx_list *ctx;
/*
* Fetch calibration data: a sensor count at room temperature (25C),
* a sensor count at a high temperature, and that temperature
*/
cal = fsl_ocotp_read_4(FSL_OCOTP_ANA1);
sc->temp_room_cnt = (cal & 0xFFF00000) >> 20;
sc->temp_high_cnt = (cal & 0x000FFF00) >> 8;
sc->temp_high_val = (cal & 0x000000FF) * 10;
/*
* Throttle to a lower cpu freq at 10C below the "hot" temperature, and
* reset back to max cpu freq at 5C below the trigger.
*/
sc->temp_throttle_val = sc->temp_high_val - 100;
sc->temp_throttle_trigger_cnt =
temp_to_count(sc, sc->temp_throttle_val);
sc->temp_throttle_reset_cnt =
temp_to_count(sc, sc->temp_throttle_val - 50);
/*
* Set the sensor to sample automatically at 16Hz (32.768KHz/0x800), set
* the throttle count, and begin making measurements.
*/
imx6_anatop_write_4(IMX6_ANALOG_TEMPMON_TEMPSENSE1, 0x0800);
imx6_anatop_write_4(IMX6_ANALOG_TEMPMON_TEMPSENSE0,
(sc->temp_throttle_trigger_cnt <<
IMX6_ANALOG_TEMPMON_TEMPSENSE0_ALARM_SHIFT) |
IMX6_ANALOG_TEMPMON_TEMPSENSE0_MEASURE);
/*
* XXX Note that the alarm-interrupt feature isn't working yet, so
* we'll use a callout handler to check at 10Hz. Make sure we have an
* initial temperature reading before starting up the callouts so we
* don't get a bogus reading of zero.
*/
while (sc->temp_last_cnt == 0)
temp_update_count(sc);
sc->temp_throttle_delay = 100 * SBT_1MS;
callout_init(&sc->temp_throttle_callout, 0);
callout_reset_sbt(&sc->temp_throttle_callout, sc->temp_throttle_delay,
0, tempmon_throttle_check, sc, 0);
ctx = device_get_sysctl_ctx(sc->dev);
SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(device_get_sysctl_tree(sc->dev)),
OID_AUTO, "temperature", CTLTYPE_INT | CTLFLAG_RD, sc, 0,
temp_sysctl_handler, "IK", "Current die temperature");
SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(device_get_sysctl_tree(sc->dev)),
OID_AUTO, "throttle_temperature", CTLTYPE_INT | CTLFLAG_RW, sc,
0, temp_throttle_sysctl_handler, "IK",
"Throttle CPU when exceeding this temperature");
}
