diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-devices-system-cpu | 6 | ||||
| -rw-r--r-- | Documentation/admin-guide/pm/cpuidle.rst | 3 | ||||
| -rw-r--r-- | Documentation/admin-guide/pm/intel_idle.rst | 246 | ||||
| -rw-r--r-- | Documentation/admin-guide/pm/working-state.rst | 1 | ||||
| -rw-r--r-- | drivers/acpi/Kconfig | 1 | ||||
| -rw-r--r-- | drivers/acpi/acpi_processor.c | 182 | ||||
| -rw-r--r-- | drivers/acpi/processor_idle.c | 174 | ||||
| -rw-r--r-- | drivers/cpuidle/cpuidle.c | 6 | ||||
| -rw-r--r-- | drivers/cpuidle/sysfs.c | 10 | ||||
| -rw-r--r-- | drivers/idle/intel_idle.c | 349 | ||||
| -rw-r--r-- | include/linux/acpi.h | 15 | ||||
| -rw-r--r-- | include/linux/cpuidle.h | 1 |
12 files changed, 766 insertions, 228 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu index fc20cde63d1e..2e0e3b45d02a 100644 --- a/Documentation/ABI/testing/sysfs-devices-system-cpu +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu @@ -196,6 +196,12 @@ Description: does not reflect it. Likewise, if one enables a deep state but a lighter state still is disabled, then this has no effect. +What: /sys/devices/system/cpu/cpuX/cpuidle/stateN/default_status +Date: December 2019 +KernelVersion: v5.6 +Contact: Linux power management list <linux-pm@vger.kernel.org> +Description: + (RO) The default status of this state, "enabled" or "disabled". What: /sys/devices/system/cpu/cpuX/cpuidle/stateN/residency Date: March 2014 diff --git a/Documentation/admin-guide/pm/cpuidle.rst b/Documentation/admin-guide/pm/cpuidle.rst index e70b365dbc60..311cd7cc2b75 100644 --- a/Documentation/admin-guide/pm/cpuidle.rst +++ b/Documentation/admin-guide/pm/cpuidle.rst @@ -506,6 +506,9 @@ object corresponding to it, as follows: ``disable`` Whether or not this idle state is disabled. +``default_status`` + The default status of this state, "enabled" or "disabled". + ``latency`` Exit latency of the idle state in microseconds. diff --git a/Documentation/admin-guide/pm/intel_idle.rst b/Documentation/admin-guide/pm/intel_idle.rst new file mode 100644 index 000000000000..afbf778035f8 --- /dev/null +++ b/Documentation/admin-guide/pm/intel_idle.rst @@ -0,0 +1,246 @@ +.. SPDX-License-Identifier: GPL-2.0 +.. include:: <isonum.txt> + +============================================== +``intel_idle`` CPU Idle Time Management Driver +============================================== + +:Copyright: |copy| 2020 Intel Corporation + +:Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> + + +General Information +=================== + +``intel_idle`` is a part of the +:doc:`CPU idle time management subsystem <cpuidle>` in the Linux kernel +(``CPUIdle``). It is the default CPU idle time management driver for the +Nehalem and later generations of Intel processors, but the level of support for +a particular processor model in it depends on whether or not it recognizes that +processor model and may also depend on information coming from the platform +firmware. [To understand ``intel_idle`` it is necessary to know how ``CPUIdle`` +works in general, so this is the time to get familiar with :doc:`cpuidle` if you +have not done that yet.] + +``intel_idle`` uses the ``MWAIT`` instruction to inform the processor that the +logical CPU executing it is idle and so it may be possible to put some of the +processor's functional blocks into low-power states. That instruction takes two +arguments (passed in the ``EAX`` and ``ECX`` registers of the target CPU), the +first of which, referred to as a *hint*, can be used by the processor to +determine what can be done (for details refer to Intel Software Developer’s +Manual [1]_). Accordingly, ``intel_idle`` refuses to work with processors in +which the support for the ``MWAIT`` instruction has been disabled (for example, +via the platform firmware configuration menu) or which do not support that +instruction at all. + +``intel_idle`` is not modular, so it cannot be unloaded, which means that the +only way to pass early-configuration-time parameters to it is via the kernel +command line. + + +.. _intel-idle-enumeration-of-states: + +Enumeration of Idle States +========================== + +Each ``MWAIT`` hint value is interpreted by the processor as a license to +reconfigure itself in a certain way in order to save energy. The processor +configurations (with reduced power draw) resulting from that are referred to +as C-states (in the ACPI terminology) or idle states. The list of meaningful +``MWAIT`` hint values and idle states (i.e. low-power configurations of the +processor) corresponding to them depends on the processor model and it may also +depend on the configuration of the platform. + +In order to create a list of available idle states required by the ``CPUIdle`` +subsystem (see :ref:`idle-states-representation` in :doc:`cpuidle`), +``intel_idle`` can use two sources of information: static tables of idle states +for different processor models included in the driver itself and the ACPI tables +of the system. The former are always used if the processor model at hand is +recognized by ``intel_idle`` and the latter are used if that is required for +the given processor model (which is the case for all server processor models +recognized by ``intel_idle``) or if the processor model is not recognized. + +If the ACPI tables are going to be used for building the list of available idle +states, ``intel_idle`` first looks for a ``_CST`` object under one of the ACPI +objects corresponding to the CPUs in the system (refer to the ACPI specification +[2]_ for the description of ``_CST`` and its output package). Because the +``CPUIdle`` subsystem expects that the list of idle states supplied by the +driver will be suitable for all of the CPUs handled by it and ``intel_idle`` is +registered as the ``CPUIdle`` driver for all of the CPUs in the system, the +driver looks for the first ``_CST`` object returning at least one valid idle +state description and such that all of the idle states included in its return +package are of the FFH (Functional Fixed Hardware) type, which means that the +``MWAIT`` instruction is expected to be used to tell the processor that it can +enter one of them. The return package of that ``_CST`` is then assumed to be +applicable to all of the other CPUs in the system and the idle state +descriptions extracted from it are stored in a preliminary list of idle states +coming from the ACPI tables. [This step is skipped if ``intel_idle`` is +configured to ignore the ACPI tables; see `below <intel-idle-parameters_>`_.] + +Next, the first (index 0) entry in the list of available idle states is +initialized to represent a "polling idle state" (a pseudo-idle state in which +the target CPU continuously fetches and executes instructions), and the +subsequent (real) idle state entries are populated as follows. + +If the processor model at hand is recognized by ``intel_idle``, there is a +(static) table of idle state descriptions for it in the driver. In that case, +the "internal" table is the primary source of information on idle states and the +information from it is copied to the final list of available idle states. If +using the ACPI tables for the enumeration of idle states is not required +(depending on the processor model), all of the listed idle state are enabled by +default (so all of them will be taken into consideration by ``CPUIdle`` +governors during CPU idle state selection). Otherwise, some of the listed idle +states may not be enabled by default if there are no matching entries in the +preliminary list of idle states coming from the ACPI tables. In that case user +space still can enable them later (on a per-CPU basis) with the help of +the ``disable`` idle state attribute in ``sysfs`` (see +:ref:`idle-states-representation` in :doc:`cpuidle`). This basically means that +the idle states "known" to the driver may not be enabled by default if they have +not been exposed by the platform firmware (through the ACPI tables). + +If the given processor model is not recognized by ``intel_idle``, but it +supports ``MWAIT``, the preliminary list of idle states coming from the ACPI +tables is used for building the final list that will be supplied to the +``CPUIdle`` core during driver registration. For each idle state in that list, +the description, ``MWAIT`` hint and exit latency are copied to the corresponding +entry in the final list of idle states. The name of the idle state represented +by it (to be returned by the ``name`` idle state attribute in ``sysfs``) is +"CX_ACPI", where X is the index of that idle state in the final list (note that +the minimum value of X is 1, because 0 is reserved for the "polling" state), and +its target residency is based on the exit latency value. Specifically, for +C1-type idle states the exit latency value is also used as the target residency +(for compatibility with the majority of the "internal" tables of idle states for +various processor models recognized by ``intel_idle``) and for the other idle +state types (C2 and C3) the target residency value is 3 times the exit latency +(again, that is because it reflects the target residency to exit latency ratio +in the majority of cases for the processor models recognized by ``intel_idle``). +All of the idle states in the final list are enabled by default in this case. + + +.. _intel-idle-initialization: + +Initialization +============== + +The initialization of ``intel_idle`` starts with checking if the kernel command +line options forbid the use of the ``MWAIT`` instruction. If that is the case, +an error code is returned right away. + +The next step is to check whether or not the processor model is known to the +driver, which determines the idle states enumeration method (see +`above <intel-idle-enumeration-of-states_>`_), and whether or not the processor +supports ``MWAIT`` (the initialization fails if that is not the case). Then, +the ``MWAIT`` support in the processor is enumerated through ``CPUID`` and the +driver initialization fails if the level of support is not as expected (for +example, if the total number of ``MWAIT`` substates returned is 0). + +Next, if the driver is not configured to ignore the ACPI tables (see +`below <intel-idle-parameters_>`_), the idle states information provided by the +platform firmware is extracted from them. + +Then, ``CPUIdle`` device objects are allocated for all CPUs and the list of +available idle states is created as explained +`above <intel-idle-enumeration-of-states_>`_. + +Finally, ``intel_idle`` is registered with the help of cpuidle_register_driver() +as the ``CPUIdle`` driver for all CPUs in the system and a CPU online callback +for configuring individual CPUs is registered via cpuhp_setup_state(), which +(among other things) causes the callback routine to be invoked for all of the +CPUs present in the system at that time (each CPU executes its own instance of +the callback routine). That routine registers a ``CPUIdle`` device for the CPU +running it (which enables the ``CPUIdle`` subsystem to operate that CPU) and +optionally performs some CPU-specific initialization actions that may be +required for the given processor model. + + +.. _intel-idle-parameters: + +Kernel Command Line Options and Module Parameters +================================================= + +The *x86* architecture support code recognizes three kernel command line +options related to CPU idle time management: ``idle=poll``, ``idle=halt``, +and ``idle=nomwait``. If any of them is present in the kernel command line, the +``MWAIT`` instruction is not allowed to be used, so the initialization of +``intel_idle`` will fail. + +Apart from that there are two module parameters recognized by ``intel_idle`` +itself that can be set via the kernel command line (they cannot be updated via +sysfs, so that is the only way to change their values). + +The ``max_cstate`` parameter value is the maximum idle state index in the list +of idle states supplied to the ``CPUIdle`` core during the registration of the +driver. It is also the maximum number of regular (non-polling) idle states that +can be used by ``intel_idle``, so the enumeration of idle states is terminated +after finding that number of usable idle states (the other idle states that +potentially might have been used if ``max_cstate`` had been greater are not +taken into consideration at all). Setting ``max_cstate`` can prevent +``intel_idle`` from exposing idle states that are regarded as "too deep" for +some reason to the ``CPUIdle`` core, but it does so by making them effectively +invisible until the system is shut down and started again which may not always +be desirable. In practice, it is only really necessary to do that if the idle +states in question cannot be enabled during system startup, because in the +working state of the system the CPU power management quality of service (PM +QoS) feature can be used to prevent ``CPUIdle`` from touching those idle states +even if they have been enumerated (see :ref:`cpu-pm-qos` in :doc:`cpuidle`). +Setting ``max_cstate`` to 0 causes the ``intel_idle`` initialization to fail. + +The ``noacpi`` module parameter (which is 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 (it is unset by default). + + +.. _intel-idle-core-and-package-idle-states: + +Core and Package Levels of Idle States +====================================== + +Typically, in a processor supporting the ``MWAIT`` instruction there are (at +least) two levels of idle states (or C-states). One level, referred to as +"core C-states", covers individual cores in the processor, whereas the other +level, referred to as "package C-states", covers the entire processor package +and it may also involve other components of the system (GPUs, memory +controllers, I/O hubs etc.). + +Some of the ``MWAIT`` hint values allow the processor to use core C-states only +(most importantly, that is the case for the ``MWAIT`` hint value corresponding +to the ``C1`` idle state), but the majority of them give it a license to put +the target core (i.e. the core containing the logical CPU executing ``MWAIT`` +with the given hint value) into a specific core C-state and then (if possible) +to enter a specific package C-state at the deeper level. For example, the +``MWAIT`` hint value representing the ``C3`` idle state allows the processor to +put the target core into the low-power state referred to as "core ``C3``" (or +``CC3``), which happens if all of the logical CPUs (SMT siblings) in that core +have executed ``MWAIT`` with the ``C3`` hint value (or with a hint value +representing a deeper idle state), and in addition to that (in the majority of +cases) it gives the processor a license to put the entire package (possibly +including some non-CPU components such as a GPU or a memory controller) into the +low-power state referred to as "package ``C3``" (or ``PC3``), which happens if +all of the cores have gone into the ``CC3`` state and (possibly) some additional +conditions are satisfied (for instance, if the GPU is covered by ``PC3``, it may +be required to be in a certain GPU-specific low-power state for ``PC3`` to be +reachable). + +As a rule, there is no simple way to make the processor use core C-states only +if the conditions for entering the corresponding package C-states are met, so +the logical CPU executing ``MWAIT`` with a hint value that is not core-level +only (like for ``C1``) must always assume that this may cause the processor to +enter a package C-state. [That is why the exit latency and target residency +values corresponding to the majority of ``MWAIT`` hint values in the "internal" +tables of idle states in ``intel_idle`` reflect the properties of package +C-states.] If using package C-states is not desirable at all, either +:ref:`PM QoS <cpu-pm-qos>` or the ``max_cstate`` module parameter of +``intel_idle`` described `above <intel-idle-parameters_>`_ must be used to +restrict the range of permissible idle states to the ones with core-level only +``MWAIT`` hint values (like ``C1``). + + +References +========== + +.. [1] *Intel® 64 and IA-32 Architectures Software Developer’s Manual Volume 2B*, + https://www.intel.com/content/www/us/en/architecture-and-technology/64-ia-32-architectures-software-developer-vol-2b-manual.html + +.. [2] *Advanced Configuration and Power Interface (ACPI) Specification*, + https://uefi.org/specifications diff --git a/Documentation/admin-guide/pm/working-state.rst b/Documentation/admin-guide/pm/working-state.rst index fc298eb1234b..88f717e59a42 100644 --- a/Documentation/admin-guide/pm/working-state.rst +++ b/Documentation/admin-guide/pm/working-state.rst @@ -8,6 +8,7 @@ Working-State Power Management :maxdepth: 2 cpuidle + intel_idle cpufreq intel_pstate intel_epb diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 002838d23b86..cc57bab146b5 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -241,6 +241,7 @@ config ACPI_CPU_FREQ_PSS config ACPI_PROCESSOR_CSTATE def_bool y + depends on ACPI_PROCESSOR depends on IA64 || X86 config ACPI_PROCESSOR_IDLE diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c index 2c4dda0787e8..5379bc3f275d 100644 --- a/drivers/acpi/acpi_processor.c +++ b/drivers/acpi/acpi_processor.c @@ -705,3 +705,185 @@ void __init acpi_processor_init(void) acpi_scan_add_handler_with_hotplug(&processor_handler, "processor"); acpi_scan_add_handler(&processor_container_handler); } + +#ifdef CONFIG_ACPI_PROCESSOR_CSTATE +/** + * acpi_processor_claim_cst_control - Request _CST control from the platform. + */ +bool acpi_processor_claim_cst_control(void) +{ + static bool cst_control_claimed; + acpi_status status; + + if (!acpi_gbl_FADT.cst_control || cst_control_claimed) + return true; + + status = acpi_os_write_port(acpi_gbl_FADT.smi_command, + acpi_gbl_FADT.cst_control, 8); + if (ACPI_FAILURE(status)) { + pr_warn("ACPI: Failed to claim processor _CST control\n"); + return false; + } + + cst_control_claimed = true; + return true; +} +EXPORT_SYMBOL_GPL(acpi_processor_claim_cst_control); + +/** + * acpi_processor_evaluate_cst - Evaluate the processor _CST control method. + * @handle: ACPI handle of the processor object containing the _CST. + * @cpu: The numeric ID of the target CPU. + * @info: Object write the C-states information into. + * + * Extract the C-state information for the given CPU from the output of the _CST + * control method under the corresponding ACPI processor object (or processor + * device object) and populate @info with it. + * + * If any ACPI_ADR_SPACE_FIXED_HARDWARE C-states are found, invoke + * acpi_processor_ffh_cstate_probe() to verify them and update the + * cpu_cstate_entry data for @cpu. + */ +int acpi_processor_evaluate_cst(acpi_handle handle, u32 cpu, + struct acpi_processor_power *info) +{ + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + union acpi_object *cst; + acpi_status status; + u64 count; + int last_index = 0; + int i, ret = 0; + + status = acpi_evaluate_object(handle, "_CST", NULL, &buffer); + if (ACPI_FAILURE(status)) { + acpi_handle_debug(handle, "No _CST\n"); + return -ENODEV; + } + + cst = buffer.pointer; + + /* There must be at least 2 elements. */ + if (!cst || cst->type != ACPI_TYPE_PACKAGE || cst->package.count < 2) { + acpi_handle_warn(handle, "Invalid _CST output\n"); + ret = -EFAULT; + goto end; + } + + count = cst->package.elements[0].integer.value; + + /* Validate the number of C-states. */ + if (count < 1 || count != cst->package.count - 1) { + acpi_handle_warn(handle, "Inconsistent _CST data\n"); + ret = -EFAULT; + goto end; + } + + for (i = 1; i <= count; i++) { + union acpi_object *element; + union acpi_object *obj; + struct acpi_power_register *reg; + struct acpi_processor_cx cx; + + /* + * If there is not enough space for all C-states, skip the + * excess ones and log a warning. + */ + if (last_index >= ACPI_PROCESSOR_MAX_POWER - 1) { + acpi_handle_warn(handle, + "No room for more idle states (limit: %d)\n", + ACPI_PROCESSOR_MAX_POWER - 1); + break; + } + + memset(&cx, 0, sizeof(cx)); + + element = &cst->package.elements[i]; + if (element->type != ACPI_TYPE_PACKAGE) + continue; + + if (element->package.count != 4) + continue; + + obj = &element->package.elements[0]; + + if (obj->type != ACPI_TYPE_BUFFER) + continue; + + reg = (struct acpi_power_register *)obj->buffer.pointer; + + obj = &element->package.elements[1]; + if (obj->type != ACPI_TYPE_INTEGER) + continue; + + cx.type = obj->integer.value; + /* + * There are known cases in which the _CST output does not + * contain C1, so if the type of the first state found is not + * C1, leave an empty slot for C1 to be filled in later. + */ + if (i == 1 && cx.type != ACPI_STATE_C1) + last_index = 1; + + cx.address = reg->address; + cx.index = last_index + 1; + + if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) { + if (!acpi_processor_ffh_cstate_probe(cpu, &cx, reg)) { + /* + * In the majority of cases _CST describes C1 as + * a FIXED_HARDWARE C-state, but if the command + * line forbids using MWAIT, use CSTATE_HALT for + * C1 regardless. + */ + if (cx.type == ACPI_STATE_C1 && + boot_option_idle_override == IDLE_NOMWAIT) { + cx.entry_method = ACPI_CSTATE_HALT; + snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT"); + } else { + cx.entry_method = ACPI_CSTATE_FFH; + } + } else if (cx.type == ACPI_STATE_C1) { + /* + * In the special case of C1, FIXED_HARDWARE can + * be handled by executing the HLT instruction. + */ + cx.entry_method = ACPI_CSTATE_HALT; + snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT"); + } else { + continue; + } + } else if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) { + cx.entry_method = ACPI_CSTATE_SYSTEMIO; + snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x", + cx.address); + } else { + continue; + } + + if (cx.type == ACPI_STATE_C1) + cx.valid = 1; + + obj = &element->package.elements[2]; + if (obj->type != ACPI_TYPE_INTEGER) + continue; + + cx.latency = obj->integer.value; + + obj = &element->package.elements[3]; + if (obj->type != ACPI_TYPE_INTEGER) + continue; + + memcpy(&info->states[++last_index], &cx, sizeof(cx)); + } + + acpi_handle_info(handle, "Found %d idle states\n", last_index); + + info->count = last_index; + + end: + kfree(buffer.pointer); + + return ret; +} +EXPORT_SYMBOL_GPL(acpi_processor_evaluate_cst); +#endif /* CONFIG_ACPI_PROCESSOR_CSTATE */ diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 2ae95df2e74f..dcc289e30166 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -299,164 +299,24 @@ static int acpi_processor_get_power_info_default(struct acpi_processor *pr) static int acpi_processor_get_power_info_cst(struct acpi_processor *pr) { - acpi_status status; - u64 count; - int current_count; - int i, ret = 0; - struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; - union acpi_object *cst; + int ret; if (nocst) return -ENODEV; - current_count = 0; - - status = acpi_evaluate_object(pr->handle, "_CST", NULL, &buffer); - if (ACPI_FAILURE(status)) { - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No _CST, giving up\n")); - return -ENODEV; - } - - cst = buffer.pointer; - - /* There must be at least 2 elements */ - if (!cst || (cst->type != ACPI_TYPE_PACKAGE) || cst->package.count < 2) { - pr_err("not enough elements in _CST\n"); - ret = -EFAULT; - goto end; - } - - count = cst->package.elements[0].integer.value; + ret = acpi_processor_evaluate_cst(pr->handle, pr->id, &pr->power); + if (ret) + return ret; - /* Validate number of power states. */ - if (count < 1 || count != cst->package.count - 1) { - pr_err("count given by _CST is not valid\n"); - ret = -EFAULT; - goto end; - } + /* + * It is expected that there will be at least 2 states, C1 and + * something else (C2 or C3), so fail if that is not the case. + */ + if (pr->power.count < 2) + return -EFAULT; - /* Tell driver that at least _CST is supported. */ pr->flags.has_cst = 1; - - for (i = 1; i <= count; i++) { - union acpi_object *element; - union acpi_object *obj; - struct acpi_power_register *reg; - struct acpi_processor_cx cx; - - memset(&cx, 0, sizeof(cx)); - - element = &(cst->package.elements[i]); - if (element->type != ACPI_TYPE_PACKAGE) - continue; - - if (element->package.count != 4) - continue; - - obj = &(element->package.elements[0]); - - if (obj->type != ACPI_TYPE_BUFFER) - continue; - - reg = (struct acpi_power_register *)obj->buffer.pointer; - - if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO && - (reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) - continue; - - /* There should be an easy way to extract an integer... */ - obj = &(element->package.elements[1]); - if (obj->type != ACPI_TYPE_INTEGER) - continue; - - cx.type = obj->integer.value; - /* - * Some buggy BIOSes won't list C1 in _CST - - * Let acpi_processor_get_power_info_default() handle them later - */ - if (i == 1 && cx.type != ACPI_STATE_C1) - current_count++; - - cx.address = reg->address; - cx.index = current_count + 1; - - cx.entry_method = ACPI_CSTATE_SYSTEMIO; - if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) { - if (acpi_processor_ffh_cstate_probe - (pr->id, &cx, reg) == 0) { - cx.entry_method = ACPI_CSTATE_FFH; - } else if (cx.type == ACPI_STATE_C1) { - /* - * C1 is a special case where FIXED_HARDWARE - * can be handled in non-MWAIT way as well. - * In that case, save this _CST entry info. - * Otherwise, ignore this info and continue. - */ - cx.entry_method = ACPI_CSTATE_HALT; - snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT"); - } else { - continue; - } - if (cx.type == ACPI_STATE_C1 && - (boot_option_idle_override == IDLE_NOMWAIT)) { - /* - * In most cases the C1 space_id obtained from - * _CST object is FIXED_HARDWARE access mode. - * But when the option of idle=halt is added, - * the entry_method type should be changed from - * CSTATE_FFH to CSTATE_HALT. - * When the option of idle=nomwait is added, - * the C1 entry_method type should be - * CSTATE_HALT. - */ - cx.entry_method = ACPI_CSTATE_HALT; - snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT"); - } - } else { - snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x", - cx.address); - } - - if (cx.type == ACPI_STATE_C1) { - cx.valid = 1; - } - - obj = &(element->package.elements[2]); - if (obj->type != ACPI_TYPE_INTEGER) - continue; - - cx.latency = obj->integer.value; - - obj = &(element->package.elements[3]); - if (obj->type != ACPI_TYPE_INTEGER) - continue; - - current_count++; - memcpy(&(pr->power.states[current_count]), &cx, sizeof(cx)); - - /* - * We support total ACPI_PROCESSOR_MAX_POWER - 1 - * (From 1 through ACPI_PROCESSOR_MAX_POWER - 1) - */ - if (current_count >= (ACPI_PROCESSOR_MAX_POWER - 1)) { - pr_warn("Limiting number of power states to max (%d)\n", - ACPI_PROCESSOR_MAX_POWER); - pr_warn("Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n"); - break; - } - } - - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d power states\n", - current_count)); - - /* Validate number of power states discovered */ - if (current_count < 2) - ret = -EFAULT; - - end: - kfree(buffer.pointer); - - return ret; + return 0; } static void acpi_processor_power_verify_c3(struct acpi_processor *pr, @@ -909,7 +769,6 @@ static int acpi_processor_setup_cstates(struct acpi_processor *pr) static inline void acpi_processor_cstate_first_run_checks(void) { - acpi_status status; static int first_run; if (first_run) @@ -921,13 +780,10 @@ static inline void acpi_processor_cstate_first_run_checks(void) max_cstate); first_run++; - if (acpi_gbl_FADT.cst_control && !nocst) { - status = acpi_os_write_port(acpi_gbl_FADT.smi_command, - acpi_gbl_FADT.cst_control, 8); - if (ACPI_FAILURE(status)) - ACPI_EXCEPTION((AE_INFO, status, - "Notifying BIOS of _CST ability failed")); - } + if (nocst) + return; + + acpi_processor_claim_cst_control(); } #else diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index ad064d84da5e..de81298051b3 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -575,10 +575,14 @@ static int __cpuidle_register_device(struct cpuidle_device *dev) if (!try_module_get(drv->owner)) return -EINVAL; - for (i = 0; i < drv->state_count; i++) + for (i = 0; i < drv->state_count; i++) { if (drv->states[i].flags & CPUIDLE_FLAG_UNUSABLE) dev->states_usage[i].disable |= CPUIDLE_STATE_DISABLED_BY_DRIVER; + if (drv->states[i].flags & CPUIDLE_FLAG_OFF) + dev->states_usage[i].disable |= CPUIDLE_STATE_DISABLED_BY_USER; + } + per_cpu(cpuidle_devices, dev->cpu) = dev; list_add(&dev->device_list, &cpuidle_detected_devices); diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c index 1909584e1e50..cdeedbf02646 100644 --- a/drivers/cpuidle/sysfs.c +++ b/drivers/cpuidle/sysfs.c @@ -329,6 +329,14 @@ static ssize_t store_state_disable(struct cpuidle_state *state, return size; } +static ssize_t show_state_default_status(struct cpuidle_state *state, + struct cpuidle_state_usage *state_usage, + char *buf) +{ + return sprintf(buf, "%s\n", + state->flags & CPUIDLE_FLAG_OFF ? "disabled" : "enabled"); +} + define_one_state_ro(name, show_state_name); define_one_state_ro(desc, show_state_desc); define_one_state_ro(latency, show_state_exit_latency); @@ -339,6 +347,7 @@ define_one_state_ro(time, show_state_time); define_one_state_rw(disable, show_state_disable, store_state_disable); define_one_state_ro(above, show_state_above); define_one_state_ro(below, show_state_below); +define_one_state_ro(default_status, show_state_default_status); static struct attribute *cpuidle_state_default_attrs[] = { &attr_name.attr, @@ -351,6 +360,7 @@ static struct attribute *cpuidle_state_default_attrs[] = { &attr_disable.attr, &attr_above.attr, &attr_below.attr, + &attr_default_status.attr, NULL }; diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index 75fd2a7b0842..1467490adfc3 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -41,6 +41,7 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include <linux/acpi.h> #include <linux/kernel.h> #include <linux/cpuidle.h> #include <linux/tick.h> @@ -79,6 +80,7 @@ struct idle_cpu { unsigned long auto_demotion_disable_flags; bool byt_auto_demotion_disable_flag; bool disable_promotion_to_c1e; + bool use_acpi; }; static const struct idle_cpu *icpu; @@ -90,6 +92,11 @@ static void intel_idle_s2idle(struct cpuidle_device *dev, static struct cpuidle_state *cpuidle_state_table; /* + * Enable this state by default even if the ACPI _CST does not list it. + */ +#define CPUIDLE_FLAG_ALWAYS_ENABLE BIT(15) + +/* * Set this flag for states where the HW flushes the TLB for us * and so we don't need cross-calls to keep it consistent. * If this flag is set, SW flushes the TLB, so even if the @@ -124,7 +131,7 @@ static struct cpuidle_state nehalem_cstates[] = { { .name = "C1E", .desc = "MWAIT 0x01", - .flags = MWAIT2flg(0x01), + .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, @@ -161,7 +168,7 @@ static struct cpuidle_state snb_cstates[] = { { .name = "C1E", .desc = "MWAIT 0x01", - .flags = MWAIT2flg(0x01), + .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, @@ -296,7 +303,7 @@ static struct cpuidle_state ivb_cstates[] = { { .name = "C1E", .desc = "MWAIT 0x01", - .flags = MWAIT2flg(0x01), + .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, @@ -341,7 +348,7 @@ static struct cpuidle_state ivt_cstates[] = { { .name = "C1E", .desc = "MWAIT 0x01", - .flags = MWAIT2flg(0x01), + .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 80, .enter = &intel_idle, @@ -378,7 +385,7 @@ static struct cpuidle_state ivt_cstates_4s[] = { { .name = "C1E", .desc = "MWAIT 0x01", - .flags = MWAIT2flg(0x01), + .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 250, .enter = &intel_idle, @@ -415,7 +422,7 @@ static struct cpuidle_state ivt_cstates_8s[] = { { .name = "C1E", .desc = "MWAIT 0x01", - .flags = MWAIT2flg(0x01), + .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 500, .enter = &intel_idle, @@ -452,7 +459,7 @@ static struct cpuidle_state hsw_cstates[] = { { .name = "C1E", .desc = "MWAIT 0x01", - .flags = MWAIT2flg(0x01), + .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, @@ -520,7 +527,7 @@ static struct cpuidle_state bdw_cstates[] = { { .name = "C1E", .desc = "MWAIT 0x01", - .flags = MWAIT2flg(0x01), + .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, @@ -589,7 +596,7 @@ static struct cpuidle_state skl_cstates[] = { { .name = "C1E", .desc = "MWAIT 0x01", - .flags = MWAIT2flg(0x01), + .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, @@ -658,7 +665,7 @@ static struct cpuidle_state skx_cstates[] = { { .name = "C1E", .desc = "MWAIT 0x01", - .flags = MWAIT2flg(0x01), + .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, @@ -808,7 +815,7 @@ static struct cpuidle_state bxt_cstates[] = { { .name = "C1E", .desc = "MWAIT 0x01", - .flags = MWAIT2flg(0x01), + .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, @@ -869,7 +876,7 @@ static struct cpuidle_state dnv_cstates[] = { { .name = "C1E", .desc = "MWAIT 0x01", - .flags = MWAIT2flg(0x01), + .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, @@ -944,6 +951,22 @@ static void intel_idle_s2idle(struct cpuidle_device *dev, mwait_idle_with_hints(eax, ecx); } +static bool intel_idle_verify_cstate(unsigned int mwait_hint) +{ + unsigned int mwait_cstate = MWAIT_HINT2CSTATE(mwait_hint) + 1; + unsigned int num_substates = (mwait_substates >> mwait_cstate * 4) & + MWAIT_SUBSTATE_MASK; + + /* Ignore the C-state if there are NO sub-states in CPUID for it. */ + if (num_substates == 0) + return false; + + if (mwait_cstate > 2 && !boot_cpu_has(X86_FEATURE_NONSTOP_TSC)) + mark_tsc_unstable("TSC halts in idle states deeper than C2"); + + return true; +} + static void __setup_broadcast_timer(bool on) { if (on) @@ -975,6 +998,13 @@ static const struct idle_cpu idle_cpu_nehalem = { .disable_promotion_to_c1e = true, }; +static const struct idle_cpu idle_cpu_nhx = { + .state_table = nehalem_cstates, + .auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE, + .disable_promotion_to_c1e = true, + .use_acpi = true, +}; + static const struct idle_cpu idle_cpu_atom = { .state_table = atom_cstates, }; @@ -993,6 +1023,12 @@ static const struct idle_cpu idle_cpu_snb = { .disable_promotion_to_c1e = true, }; +static const struct idle_cpu idle_cpu_snx = { + .state_table = snb_cstates, + .disable_promotion_to_c1e = true, + .use_acpi = true, +}; + static const struct idle_cpu idle_cpu_byt = { .state_table = byt_cstates, .disable_promotion_to_c1e = true, @@ -1013,6 +1049,7 @@ static const struct idle_cpu idle_cpu_ivb = { static const struct idle_cpu idle_cpu_ivt = { .state_table = ivt_cstates, .disable_promotion_to_c1e = true, + .use_acpi = true, }; static const struct idle_cpu idle_cpu_hsw = { @@ -1020,11 +1057,23 @@ static const struct idle_cpu idle_cpu_hsw = { .disable_promotion_to_c1e = true, }; +static const struct idle_cpu idle_cpu_hsx = { + .state_table = hsw_cstates, + .disable_promotion_to_c1e = true, + .use_acpi = true, +}; + static const struct idle_cpu idle_cpu_bdw = { .state_table = bdw_cstates, .disable_promotion_to_c1e = true, }; +static const struct idle_cpu idle_cpu_bdx = { + .state_table = bdw_cstates, + .disable_promotion_to_c1e = true, + .use_acpi = true, +}; + static const struct idle_cpu idle_cpu_skl = { .state_table = skl_cstates, .disable_promotion_to_c1e = true, @@ -1033,15 +1082,18 @@ static const struct idle_cpu idle_cpu_skl = { static const struct idle_cpu idle_cpu_skx = { .state_table = skx_cstates, .disable_promotion_to_c1e = true, + .use_acpi = true, }; static const struct idle_cpu idle_cpu_avn = { .state_table = avn_cstates, .disable_promotion_to_c1e = true, + .use_acpi = true, }; static const struct idle_cpu idle_cpu_knl = { .state_table = knl_cstates, + .use_acpi = true, }; static const struct idle_cpu idle_cpu_bxt = { @@ -1052,20 +1104,21 @@ static const struct idle_cpu idle_cpu_bxt = { static const struct idle_cpu idle_cpu_dnv = { .state_table = dnv_cstates, .disable_promotion_to_c1e = true, + .use_acpi = true, }; static const struct x86_cpu_id intel_idle_ids[] __initconst = { - INTEL_CPU_FAM6(NEHALEM_EP, idle_cpu_nehalem), + INTEL_CPU_FAM6(NEHALEM_EP, idle_cpu_nhx), INTEL_CPU_FAM6(NEHALEM, idle_cpu_nehalem), INTEL_CPU_FAM6(NEHALEM_G, idle_cpu_nehalem), INTEL_CPU_FAM6(WESTMERE, idle_cpu_nehalem), - INTEL_CPU_FAM6(WESTMERE_EP, idle_cpu_nehalem), - INTEL_CPU_FAM6(NEHALEM_EX, idle_cpu_nehalem), + INTEL_CPU_FAM6(WESTMERE_EP, idle_cpu_nhx), + INTEL_CPU_FAM6(NEHALEM_EX, idle_cpu_nhx), INTEL_CPU_FAM6(ATOM_BONNELL, idle_cpu_atom), INTEL_CPU_FAM6(ATOM_BONNELL_MID, idle_cpu_lincroft), - INTEL_CPU_FAM6(WESTMERE_EX, idle_cpu_nehalem), + INTEL_CPU_FAM6(WESTMERE_EX, idle_cpu_nhx), INTEL_CPU_FAM6(SANDYBRIDGE, idle_cpu_snb), - INTEL_CPU_FAM6(SANDYBRIDGE_X, idle_cpu_snb), + INTEL_CPU_FAM6(SANDYBRIDGE_X, idle_cpu_snx), INTEL_CPU_FAM6(ATOM_SALTWELL, idle_cpu_atom), INTEL_CPU_FAM6(ATOM_SILVERMONT, idle_cpu_byt), INTEL_CPU_FAM6(ATOM_SILVERMONT_MID, idle_cpu_tangier), @@ -1073,14 +1126,14 @@ static const struct x86_cpu_id intel_idle_ids[] __initconst = { INTEL_CPU_FAM6(IVYBRIDGE, idle_cpu_ivb), INTEL_CPU_FAM6(IVYBRIDGE_X, idle_cpu_ivt), INTEL_CPU_FAM6(HASWELL, idle_cpu_hsw), - INTEL_CPU_FAM6(HASWELL_X, idle_cpu_hsw), + INTEL_CPU_FAM6(HASWELL_X, idle_cpu_hsx), INTEL_CPU_FAM6(HASWELL_L, idle_cpu_hsw), INTEL_CPU_FAM6(HASWELL_G, idle_cpu_hsw), INTEL_CPU_FAM6(ATOM_SILVERMONT_D, idle_cpu_avn), INTEL_CPU_FAM6(BROADWELL, idle_cpu_bdw), INTEL_CPU_FAM6(BROADWELL_G, idle_cpu_bdw), - INTEL_CPU_FAM6(BROADWELL_X, idle_cpu_bdw), - INTEL_CPU_FAM6(BROADWELL_D, idle_cpu_bdw), + INTEL_CPU_FAM6(BROADWELL_X, idle_cpu_bdx), + INTEL_CPU_FAM6(BROADWELL_D, idle_cpu_bdx), INTEL_CPU_FAM6(SKYLAKE_L, idle_cpu_skl), INTEL_CPU_FAM6(SKYLAKE, idle_cpu_skl), INTEL_CPU_FAM6(KABYLAKE_L, idle_cpu_skl), @@ -1095,6 +1148,162 @@ static const struct x86_cpu_id intel_idle_ids[] __initconst = { {} }; +#define INTEL_CPU_FAM6_MWAIT \ + { X86_VENDOR_INTEL, 6, X86_MODEL_ANY, X86_FEATURE_MWAIT, 0 } + +static const struct x86_cpu_id intel_mwait_ids[] __initconst = { + INTEL_CPU_FAM6_MWAIT, + {} +}; + +static bool intel_idle_max_cstate_reached(int cstate) +{ + if (cstate + 1 > max_cstate) { + pr_info("max_cstate %d reached\n", max_cstate); + return true; + } + return false; +} + +#ifdef CONFIG_ACPI_PROCESSOR_CSTATE +#include <acpi/processor.h> + +static bool no_acpi __read_mostly; +module_param(no_acpi, bool, 0444); +MODULE_PARM_DESC(no_acpi, "Do not use ACPI _CST for building the idle states list"); + +static struct acpi_processor_power acpi_state_table; + +/** + * intel_idle_cst_usable - Check if the _CST information can be used. + * + * Check if all of the C-states listed by _CST in the max_cstate range are + * ACPI_CSTATE_FFH, which means that they should be entered via MWAIT. + */ +static bool intel_idle_cst_usable(void) +{ + int cstate, limit; + + limit = min_t(int, min_t(int, CPUIDLE_STATE_MAX, max_cstate + 1), + acpi_state_table.count); + + for (cstate = 1; cstate < limit; cstate++) { + struct acpi_processor_cx *cx = &acpi_state_table.states[cstate]; + + if (cx->entry_method != ACPI_CSTATE_FFH) + return false; + } + + return true; +} + +static bool intel_idle_acpi_cst_extract(void) +{ + unsigned int cpu; + + if (no_acpi) { + pr_debug("Not allowed to use ACPI _CST\n"); + return false; + } + + for_each_possible_cpu(cpu) { + struct acpi_processor *pr = per_cpu(processors, cpu); + + if (!pr) + continue; + + if (acpi_processor_evaluate_cst(pr->handle, cpu, &acpi_state_table)) + continue; + + acpi_state_table.count++; + + if (!intel_idle_cst_usable()) + continue; + + if (!acpi_processor_claim_cst_control()) { + acpi_state_table.count = 0; + return false; + } + + return true; + } + + pr_debug("ACPI _CST not found or not usable\n"); + return false; +} + +static void intel_idle_init_cstates_acpi(struct cpuidle_driver *drv) +{ + int cstate, limit = min_t(int, CPUIDLE_STATE_MAX, acpi_state_table.count); + + /* + * If limit > 0, intel_idle_cst_usable() has returned 'true', so all of + * the interesting states are ACPI_CSTATE_FFH. + */ + for (cstate = 1; cstate < limit; cstate++) { + struct acpi_processor_cx *cx; + struct cpuidle_state *state; + + if (intel_idle_max_cstate_reached(cstate)) + break; + + cx = &acpi_state_table.states[cstate]; + + state = &drv->states[drv->state_count++]; + + snprintf(state->name, CPUIDLE_NAME_LEN, "C%d_ACPI", cstate); + strlcpy(state->desc, cx->desc, CPUIDLE_DESC_LEN); + state->exit_latency = cx->latency; + /* + * For C1-type C-states use the same number for both the exit + * latency and target residency, because that is the case for + * C1 in the majority of the static C-states tables above. + * For the other types of C-states, however, set the target + * residency to 3 times the exit latency which should lead to + * a reasonable balance between energy-efficiency and + * performance in the majority of interesting cases. + */ + state->target_residency = cx->latency; + if (cx->type > ACPI_STATE_C1) + state->target_residency *= 3; + + state->flags = MWAIT2flg(cx->address); + if (cx->type > ACPI_STATE_C2) + state->flags |= CPUIDLE_FLAG_TLB_FLUSHED; + + state->enter = intel_idle; + state->enter_s2idle = intel_idle_s2idle; + } +} + +static bool intel_idle_off_by_default(u32 mwait_hint) +{ + int cstate, limit; + + /* + * If there are no _CST C-states, do not disable any C-states by + * default. + */ + if (!acpi_state_table.count) + return false; + + limit = min_t(int, CPUIDLE_STATE_MAX, acpi_state_table.count); + /* + * If limit > 0, intel_idle_cst_usable() has returned 'true', so all of + * the interesting states are ACPI_CSTATE_FFH. + */ + for (cstate = 1; cstate < limit; cstate++) { + if (acpi_state_table.states[cstate].address == mwait_hint) + return false; + } + return true; +} +#else /* !CONFIG_ACPI_PROCESSOR_CSTATE */ +static inline bool intel_idle_acpi_cst_extract(void) { return false; } +static inline void intel_idle_init_cstates_acpi(struct cpuidle_driver *drv) { } +static inline bool intel_idle_off_by_default(u32 mwait_hint) { return false; } +#endif /* !CONFIG_ACPI_PROCESSOR_CSTATE */ + /* * intel_idle_probe() */ @@ -1109,17 +1318,15 @@ static int __init intel_idle_probe(void) } id = x86_match_cpu(intel_idle_ids); - if (!id) { - if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL && - boot_cpu_data.x86 == 6) - pr_debug("does not run on family %d model %d\n", - boot_cpu_data.x86, boot_cpu_data.x86_model); - return -ENODEV; - } - - if (!boot_cpu_has(X86_FEATURE_MWAIT)) { - pr_debug("Please enable MWAIT in BIOS SETUP\n"); - return -ENODEV; + if (id) { + if (!boot_cpu_has(X86_FEATURE_MWAIT)) { + pr_debug("Please enable MWAIT in BIOS SETUP\n"); + return -ENODEV; + } + } else { + id = x86_match_cpu(intel_mwait_ids); + if (!id) + return -ENODEV; } if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF) @@ -1135,7 +1342,13 @@ static int __init intel_idle_probe(void) pr_debug("MWAIT substates: 0x%x\n", mwait_substates); icpu = (const struct idle_cpu *)id->driver_data; - cpuidle_state_table = icpu->state_table; + if (icpu) { + cpuidle_state_table = icpu->state_table; + if (icpu->use_acpi) + intel_idle_acpi_cst_extract(); + } else if (!intel_idle_acpi_cst_extract()) { + return -ENODEV; + } pr_debug("v" INTEL_IDLE_VERSION " model 0x%X\n", boot_cpu_data.x86_model); @@ -1317,60 +1530,39 @@ static void intel_idle_state_table_update(void) } } -/* - * intel_idle_cpuidle_driver_init() - * allocate, initialize cpuidle_states - */ -static void __init intel_idle_cpuidle_driver_init(void) +static void intel_idle_init_cstates_icpu(struct cpuidle_driver *drv) { int cstate; - struct cpuidle_driver *drv = &intel_idle_driver; - - intel_idle_state_table_update(); - - cpuidle_poll_state_init(drv); - drv->state_count = 1; for (cstate = 0; cstate < CPUIDLE_STATE_MAX; ++cstate) { - int num_substates, mwait_hint, mwait_cstate; + unsigned int mwait_hint; - if ((cpuidle_state_table[cstate].enter == NULL) && - (cpuidle_state_table[cstate].enter_s2idle == NULL)) + if (intel_idle_max_cstate_reached(cstate)) break; - if (cstate + 1 > max_cstate) { - pr_info("max_cstate %d reached\n", max_cstate); + if (!cpuidle_state_table[cstate].enter && + !cpuidle_state_table[cstate].enter_s2idle) break; - } - mwait_hint = flg2MWAIT(cpuidle_state_table[cstate].flags); - mwait_cstate = MWAIT_HINT2CSTATE(mwait_hint); - - /* number of sub-states for this state in CPUID.MWAIT */ - num_substates = (mwait_substates >> ((mwait_cstate + 1) * 4)) - & MWAIT_SUBSTATE_MASK; - - /* if NO sub-states for this state in CPUID, skip it */ - if (num_substates == 0) - continue; - - /* if state marked as disabled, skip it */ + /* If marked as unusable, skip this state. */ if (cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_UNUSABLE) { pr_debug("state %s is disabled\n", cpuidle_state_table[cstate].name); continue; } + mwait_hint = flg2MWAIT(cpuidle_state_table[cstate].flags); + if (!intel_idle_verify_cstate(mwait_hint)) + continue; - if (((mwait_cstate + 1) > 2) && - !boot_cpu_has(X86_FEATURE_NONSTOP_TSC)) - mark_tsc_unstable("TSC halts in idle" - " states deeper than C2"); + /* Structure copy. */ + drv->states[drv->state_count] = cpuidle_state_table[cstate]; - drv->states[drv->state_count] = /* structure copy */ - cpuidle_state_table[cstate]; + if (icpu->use_acpi && intel_idle_off_by_default(mwait_hint) && + !(cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_ALWAYS_ENABLE)) + drv->states[drv->state_count].flags |= CPUIDLE_FLAG_OFF; - drv->state_count += 1; + drv->state_count++; } if (icpu->byt_auto_demotion_disable_flag) { @@ -1379,6 +1571,24 @@ static void __init intel_idle_cpuidle_driver_init(void) } } +/* + * intel_idle_cpuidle_driver_init() + * allocate, initialize cpuidle_states + */ +static void __init intel_idle_cpuidle_driver_init(void) +{ + struct cpuidle_driver *drv = &intel_idle_driver; + + intel_idle_state_table_update(); + + cpuidle_poll_state_init(drv); + drv->state_count = 1; + + if (icpu) + intel_idle_init_cstates_icpu(drv); + else + intel_idle_init_cstates_acpi(drv); +} /* * intel_idle_cpu_init() @@ -1397,6 +1607,9 @@ static int intel_idle_cpu_init(unsigned int cpu) return -EIO; } + if (!icpu) + return 0; + if (icpu->auto_demotion_disable_flags) auto_demotion_disable(); diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 0f37a7d5fa77..0f24d701fbdc 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -279,6 +279,21 @@ static inline bool invalid_phys_cpuid(phys_cpuid_t phys_id) /* Validate the processor object's proc_id */ bool acpi_duplicate_processor_id(int proc_id); +/* Processor _CTS control */ +struct acpi_processor_power; + +#ifdef CONFIG_ACPI_PROCESSOR_CSTATE +bool acpi_processor_claim_cst_control(void); +int acpi_processor_evaluate_cst(acpi_handle handle, u32 cpu, + struct acpi_processor_power *info); +#else +static inline bool acpi_processor_claim_cst_control(void) { return false; } +static inline int acpi_processor_evaluate_cst(acpi_handle handle, u32 cpu, + struct acpi_processor_power *info) +{ + return -ENODEV; +} +#endif #ifdef CONFIG_ACPI_HOTPLUG_CPU /* Arch dependent functions for cpu hotplug support */ diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h index 23744d49bc22..ec2ef63771f0 100644 --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h @@ -77,6 +77,7 @@ struct cpuidle_state { #define CPUIDLE_FLAG_COUPLED BIT(1) /* state applies to multiple cpus */ #define CPUIDLE_FLAG_TIMER_STOP BIT(2) /* timer is stopped on this state */ #define CPUIDLE_FLAG_UNUSABLE BIT(3) /* avoid using this state */ +#define CPUIDLE_FLAG_OFF BIT(4) /* disable this state by default */ struct cpuidle_device_kobj; struct cpuidle_state_kobj; |