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linux/include/acpi/cppc_acpi.h

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ACPI: Introduce CPU performance controls using CPPC CPPC stands for Collaborative Processor Performance Controls and is defined in the ACPI v5.0+ spec. It describes CPU performance controls on an abstract and continuous scale allowing the platform (e.g. remote power processor) to flexibly optimize CPU performance with its knowledge of power budgets and other architecture specific knowledge. This patch adds a shim which exports commonly used functions to get and set CPPC specific controls for each CPU. This enables CPUFreq drivers to gather per CPU performance data and use with exisiting governors or even allows for customized governors which are implemented inside CPUFreq drivers. Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Reviewed-by: Al Stone <al.stone@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-02 10:01:19 -04:00
mailbox: pcc: Add PCC request and free channel declarations Exports pcc_mbox_request_channel() and pcc_mbox_free_channel() declarations into a pcc.h header file. Looks-good-to: Prashanth Prakash <pprakash@codeaurora.org> Signed-off-by: Hoan Tran <hotran@apm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-16 14:09:38 -07:00
ACPI: Introduce CPU performance controls using CPPC CPPC stands for Collaborative Processor Performance Controls and is defined in the ACPI v5.0+ spec. It describes CPU performance controls on an abstract and continuous scale allowing the platform (e.g. remote power processor) to flexibly optimize CPU performance with its knowledge of power budgets and other architecture specific knowledge. This patch adds a shim which exports commonly used functions to get and set CPPC specific controls for each CPU. This enables CPUFreq drivers to gather per CPU performance data and use with exisiting governors or even allows for customized governors which are implemented inside CPUFreq drivers. Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Reviewed-by: Al Stone <al.stone@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-02 10:01:19 -04:00
ACPI / CPPC: check for error bit in PCC status field PCC status field exposes an error bit(2) to indicate any errors during the execution of last comamnd. This patch checks the error bit before notifying success/failure to the cpufreq driver. Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-16 14:39:44 -06:00
ACPI: Introduce CPU performance controls using CPPC CPPC stands for Collaborative Processor Performance Controls and is defined in the ACPI v5.0+ spec. It describes CPU performance controls on an abstract and continuous scale allowing the platform (e.g. remote power processor) to flexibly optimize CPU performance with its knowledge of power budgets and other architecture specific knowledge. This patch adds a shim which exports commonly used functions to get and set CPPC specific controls for each CPU. This enables CPUFreq drivers to gather per CPU performance data and use with exisiting governors or even allows for customized governors which are implemented inside CPUFreq drivers. Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Reviewed-by: Al Stone <al.stone@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-02 10:01:19 -04:00
ACPI / CPPC: restructure read/writes for efficient sys mapped reg ops For cases where sys mapped CPC registers need to be accessed frequently, it helps immensly to pre-map them rather than map and unmap for each operation. e.g. case where feedback counters are sys mem map registers. Restructure cpc_read/write and the cpc_regs structure to allow pre-mapping the system addresses and unmap them when the CPU exits. Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-16 14:39:38 -06:00
ACPI: Introduce CPU performance controls using CPPC CPPC stands for Collaborative Processor Performance Controls and is defined in the ACPI v5.0+ spec. It describes CPU performance controls on an abstract and continuous scale allowing the platform (e.g. remote power processor) to flexibly optimize CPU performance with its knowledge of power budgets and other architecture specific knowledge. This patch adds a shim which exports commonly used functions to get and set CPPC specific controls for each CPU. This enables CPUFreq drivers to gather per CPU performance data and use with exisiting governors or even allows for customized governors which are implemented inside CPUFreq drivers. Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Reviewed-by: Al Stone <al.stone@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-02 10:01:19 -04:00
ACPI / CPPC: support for batching CPPC requests CPPC defined in section 8.4.7 of ACPI 6.0 specification suggests "To amortize the cost of PCC transactions, OSPM should read or write all PCC registers via a single read or write command when possible" This patch enables opportunistic batching of frequency transition requests whenever the request happen to overlap in time. Currently the access to pcc is serialized by a spin lock which does not scale well as we increase the number of cores in the system. This patch improves the scalability by allowing the differnt CPU cores to update PCC subspace in parallel and by batching requests which will reduce the certain types of operation(checking command completion bit, ringing doorbell) by a significant margin. Profiling shows significant improvement in the overall effeciency to service freq. transition requests. With this patch we observe close to 30% of the frequency transition requests being batched with other requests while running apache bench on a ARM platform with 6 independent domains(or sets of related cpus). Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-16 14:39:40 -06:00
ACPI: Introduce CPU performance controls using CPPC CPPC stands for Collaborative Processor Performance Controls and is defined in the ACPI v5.0+ spec. It describes CPU performance controls on an abstract and continuous scale allowing the platform (e.g. remote power processor) to flexibly optimize CPU performance with its knowledge of power budgets and other architecture specific knowledge. This patch adds a shim which exports commonly used functions to get and set CPPC specific controls for each CPU. This enables CPUFreq drivers to gather per CPU performance data and use with exisiting governors or even allows for customized governors which are implemented inside CPUFreq drivers. Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Reviewed-by: Al Stone <al.stone@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-02 10:01:19 -04:00
ACPI / CPPC: add sysfs support to compute delivered performance The CPPC tables contain entries for per CPU feedback counters which allows us to compute the delivered performance over a given interval of time. The math for delivered performance per the CPPCv5.0+ spec is: reference perf * delta(delivered perf ctr)/delta(ref perf ctr) Maintaining deltas of the counters in the kernel is messy, as it depends on when the reads are triggered. (e.g. via the cpufreq ->get() interface). Also the ->get() interace only returns one value, so cant return raw values. So instead, leave it to userspace to keep track of raw values and do its math for CPUs it cares about. delivered and reference perf counters are exposed via the same sysfs file to avoid the potential "skid", if these values are read individually from userspace. Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org> Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-16 14:39:42 -06:00
ACPI: Introduce CPU performance controls using CPPC CPPC stands for Collaborative Processor Performance Controls and is defined in the ACPI v5.0+ spec. It describes CPU performance controls on an abstract and continuous scale allowing the platform (e.g. remote power processor) to flexibly optimize CPU performance with its knowledge of power budgets and other architecture specific knowledge. This patch adds a shim which exports commonly used functions to get and set CPPC specific controls for each CPU. This enables CPUFreq drivers to gather per CPU performance data and use with exisiting governors or even allows for customized governors which are implemented inside CPUFreq drivers. Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Reviewed-by: Al Stone <al.stone@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-02 10:01:19 -04:00
ACPI / CPPC: add sysfs support to compute delivered performance The CPPC tables contain entries for per CPU feedback counters which allows us to compute the delivered performance over a given interval of time. The math for delivered performance per the CPPCv5.0+ spec is: reference perf * delta(delivered perf ctr)/delta(ref perf ctr) Maintaining deltas of the counters in the kernel is messy, as it depends on when the reads are triggered. (e.g. via the cpufreq ->get() interface). Also the ->get() interace only returns one value, so cant return raw values. So instead, leave it to userspace to keep track of raw values and do its math for CPUs it cares about. delivered and reference perf counters are exposed via the same sysfs file to avoid the potential "skid", if these values are read individually from userspace. Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org> Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-16 14:39:42 -06:00
ACPI: Introduce CPU performance controls using CPPC CPPC stands for Collaborative Processor Performance Controls and is defined in the ACPI v5.0+ spec. It describes CPU performance controls on an abstract and continuous scale allowing the platform (e.g. remote power processor) to flexibly optimize CPU performance with its knowledge of power budgets and other architecture specific knowledge. This patch adds a shim which exports commonly used functions to get and set CPPC specific controls for each CPU. This enables CPUFreq drivers to gather per CPU performance data and use with exisiting governors or even allows for customized governors which are implemented inside CPUFreq drivers. Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Reviewed-by: Al Stone <al.stone@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-02 10:01:19 -04:00
ACPI / CPPC: Add prefix cppc to cpudata structure name Since struct cpudata is defined in a header file, add prefix cppc_ to make it not a generic name. Otherwise it causes compile issue in locally define structure with the same name. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-01 13:37:11 -07:00
ACPI: Introduce CPU performance controls using CPPC CPPC stands for Collaborative Processor Performance Controls and is defined in the ACPI v5.0+ spec. It describes CPU performance controls on an abstract and continuous scale allowing the platform (e.g. remote power processor) to flexibly optimize CPU performance with its knowledge of power budgets and other architecture specific knowledge. This patch adds a shim which exports commonly used functions to get and set CPPC specific controls for each CPU. This enables CPUFreq drivers to gather per CPU performance data and use with exisiting governors or even allows for customized governors which are implemented inside CPUFreq drivers. Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Reviewed-by: Al Stone <al.stone@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-02 10:01:19 -04:00
ACPI / CPPC: Add prefix cppc to cpudata structure name Since struct cpudata is defined in a header file, add prefix cppc_ to make it not a generic name. Otherwise it causes compile issue in locally define structure with the same name. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-01 13:37:11 -07:00
ACPI / CPPC: set a non-zero value for transition_latency Compute the expected transition latency for frequency transitions using the values from the PCCT tables when the desired perf register is in PCC. Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org> Reviewed-by: Alexey Klimov <alexey.klimov@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-16 14:39:41 -06:00
ACPI: Introduce CPU performance controls using CPPC CPPC stands for Collaborative Processor Performance Controls and is defined in the ACPI v5.0+ spec. It describes CPU performance controls on an abstract and continuous scale allowing the platform (e.g. remote power processor) to flexibly optimize CPU performance with its knowledge of power budgets and other architecture specific knowledge. This patch adds a shim which exports commonly used functions to get and set CPPC specific controls for each CPU. This enables CPUFreq drivers to gather per CPU performance data and use with exisiting governors or even allows for customized governors which are implemented inside CPUFreq drivers. Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Reviewed-by: Al Stone <al.stone@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-02 10:01:19 -04:00