From: Len Brown Date: Sun, 12 Aug 2007 04:12:35 +0000 (-0400) Subject: ACPI: thermal: create "thermal.psv=" to override passive trip points X-Git-Tag: v2.6.23-rc3~5^2~5^2~3 X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=a70cdc5200b0eb9fc3ef64efb29baac9b2cf2431;p=linux-2.6-omap-h63xx.git ACPI: thermal: create "thermal.psv=" to override passive trip points "thermal.psv=-1" disables passive trip points for all ACPI thermal zones. "thermal.psv=C", where 'C' is degrees Celsius, overrides all existing passive trip points for all ACPI thermal zones. thermal.psv is checked at module load time, and in response to trip-point change events. Note that if the system does not deliver thermal zone temperature change events near the new trip-point, then it will not be noticed. To force your custom trip point to be noticed, you may need to enable polling: eg. thermal.tzp=3000 invokes polling every 5 minutes. Note that once passive thermal throttling is invoked, it has its own internal Thermal Sampling Period (_TSP), that is unrelated to _TZP. WARNING: disabling or raising a thermal trip point may result in increased running temperature and shorter hardware lifetime on some systems. Signed-off-by: Len Brown --- diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index ed7d7913af8..52e1c2d26a2 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1823,6 +1823,10 @@ and is between 256 and 4096 characters. It is defined in the file thermal.off= [HW,ACPI] 1: disable ACPI thermal control + thermal.psv= [HW,ACPI] + -1: disable all passive trip points + : override all passive trip points to this value + thermal.tzp= [HW,ACPI] Specify global default ACPI thermal zone polling rate : poll all this frequency diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c index b6b3bec8454..74e25be8abc 100644 --- a/drivers/acpi/thermal.c +++ b/drivers/acpi/thermal.c @@ -82,6 +82,10 @@ static int off; module_param(off, int, 0); MODULE_PARM_DESC(off, "Set to disable ACPI thermal support.\n"); +static int psv; +module_param(psv, int, 0644); +MODULE_PARM_DESC(psv, "Disable or override all passive trip points.\n"); + static int acpi_thermal_add(struct acpi_device *device); static int acpi_thermal_remove(struct acpi_device *device, int type); static int acpi_thermal_resume(struct acpi_device *device); @@ -343,9 +347,16 @@ static int acpi_thermal_get_trip_points(struct acpi_thermal *tz) /* Passive: Processors (optional) */ - status = - acpi_evaluate_integer(tz->device->handle, "_PSV", NULL, - &tz->trips.passive.temperature); + if (psv == -1) { + status = AE_SUPPORT; + } else if (psv > 0) { + tz->trips.passive.temperature = CELSIUS_TO_KELVIN(psv); + status = AE_OK; + } else { + status = acpi_evaluate_integer(tz->device->handle, + "_PSV", NULL, &tz->trips.passive.temperature); + } + if (ACPI_FAILURE(status)) { tz->trips.passive.flags.valid = 0; ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No passive threshold\n"));