diff options
| -rw-r--r-- | Documentation/admin-guide/pm/intel_idle.rst | 18 | ||||
| -rw-r--r-- | drivers/idle/intel_idle.c | 14 |
2 files changed, 27 insertions, 5 deletions
diff --git a/Documentation/admin-guide/pm/intel_idle.rst b/Documentation/admin-guide/pm/intel_idle.rst index 39bd6ecce7de..5940528146eb 100644 --- a/Documentation/admin-guide/pm/intel_idle.rst +++ b/Documentation/admin-guide/pm/intel_idle.rst @@ -192,11 +192,19 @@ even if they have been enumerated (see :ref:`cpu-pm-qos` in Documentation/admin-guide/pm/cpuidle.rst). Setting ``max_cstate`` to 0 causes the ``intel_idle`` initialization to fail. -The ``no_acpi`` and ``use_acpi`` module parameters (recognized by ``intel_idle`` -if the kernel has been configured with ACPI support) can be set to make the -driver ignore the system's ACPI tables entirely or use them for all of the -recognized processor models, respectively (they both are unset by default and -``use_acpi`` has no effect if ``no_acpi`` is set). +The ``no_acpi``, ``use_acpi`` and ``no_native`` module parameters are +recognized by ``intel_idle`` if the kernel has been configured with ACPI +support. In the case that ACPI is not configured these flags have no impact +on functionality. + +``no_acpi`` - Do not use ACPI at all. Only native mode is available, no +ACPI mode. + +``use_acpi`` - No-op in ACPI mode, the driver will consult ACPI tables for +C-states on/off status in native mode. + +``no_native`` - Work only in ACPI mode, no native mode available (ignore +all custom tables). The value of the ``states_off`` module parameter (0 by default) represents a list of idle states to be disabled by default in the form of a bitmask. diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index 324814dc34fa..0f4247e3070c 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -1692,6 +1692,10 @@ static bool force_use_acpi __read_mostly; /* No effect if no_acpi is set. */ module_param_named(use_acpi, force_use_acpi, bool, 0444); MODULE_PARM_DESC(use_acpi, "Use ACPI _CST for building the idle states list"); +static bool no_native __read_mostly; /* No effect if no_acpi is set. */ +module_param_named(no_native, no_native, bool, 0444); +MODULE_PARM_DESC(no_native, "Ignore cpu specific (native) idle states in lieu of ACPI idle states"); + static struct acpi_processor_power acpi_state_table __initdata; /** @@ -1831,6 +1835,11 @@ static bool __init intel_idle_off_by_default(unsigned int flags, u32 mwait_hint) } return true; } + +static inline bool ignore_native(void) +{ + return no_native && !no_acpi; +} #else /* !CONFIG_ACPI_PROCESSOR_CSTATE */ #define force_use_acpi (false) @@ -1840,6 +1849,7 @@ static inline bool intel_idle_off_by_default(unsigned int flags, u32 mwait_hint) { return false; } +static inline bool ignore_native(void) { return false; } #endif /* !CONFIG_ACPI_PROCESSOR_CSTATE */ /** @@ -2333,6 +2343,10 @@ static int __init intel_idle_init(void) pr_debug("MWAIT substates: 0x%x\n", mwait_substates); icpu = (const struct idle_cpu *)id->driver_data; + if (icpu && ignore_native()) { + pr_debug("ignoring native CPU idle states\n"); + icpu = NULL; + } if (icpu) { if (icpu->state_table) cpuidle_state_table = icpu->state_table; |