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2016-10-14Merge tag 'pm-extra-4.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more power management updates from Rafael Wysocki: "This includes a couple of fixes for cpufreq regressions introduced in 4.8, a rework of the intel_pstate algorithm used on Atom processors (that took some time to test) plus a fix and a couple of cleanups in that driver, a CPPC cpufreq driver fix, and a some devfreq fixes and cleanups (core and exynos-nocp). Specifics: - Fix two cpufreq regressions causing undesirable changes in behavior to appear (one in the core and one in the conservative governor) introduced during the 4.8 cycle (Aaro Koskinen, Rafael Wysocki). - Fix the way the intel_pstate driver accesses MSRs related to the hardware-managed P-states (HWP) feature during the initialization which currently is unsafe and may cause the processor to generate a general protection fault (Srinivas Pandruvada). - Rework the intel_pstate's P-state selection algorithm used on Atom processors to avoid known problems with the current one and to make the computation more straightforward, which also happens to improve performance in multiple benchmarks a bit (Rafael Wysocki). - Improve two comments in the intel_pstate driver (Rafael Wysocki). - Fix the desired performance computation in the CPPC cpufreq driver (Hoan Tran). - Fix the devfreq core to avoid printing misleading error messages in some cases (Tobias Jakobi). - Fix the error code path in devfreq_add_device() to use proper locking around list modifications (Axel Lin). - Fix a build failure and remove a couple of redundant updates of variables in the exynos-nocp devfreq driver (Axel Lin)" * tag 'pm-extra-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: cpufreq: CPPC: Correct desired_perf calculation cpufreq: conservative: Fix next frequency selection cpufreq: skip invalid entries when searching the frequency cpufreq: intel_pstate: Fix struct pstate_adjust_policy kerneldoc cpufreq: intel_pstate: Proportional algorithm for Atom PM / devfreq: Skip status update on uninitialized previous_freq PM / devfreq: Add proper locking around list_del() PM / devfreq: exynos-nocp: Remove redundant code PM / devfreq: exynos-nocp: Select REGMAP_MMIO cpufreq: intel_pstate: Clarify comment in get_target_pstate_use_performance() cpufreq: intel_pstate: Fix unsafe HWP MSR access
2016-10-13cpufreq: CPPC: Correct desired_perf calculationHoan Tran
The desired_perf is an abstract performance number. Its value should be in the range of [lowest perf, highest perf] of CPPC. The correct calculation is desired_perf = freq * cppc_highest_perf / cppc_dmi_max_khz And cppc_cpufreq_set_target() returns if desired_perf is exactly the same with the old perf. Signed-off-by: Hoan Tran <hotran@apm.com> Reviewed-by: Prashanth Prakash <pprakash@codeaurora.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-10-03Merge tag 'acpi-4.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI updates from Rafael Wysocki: "First off, the ACPICA code in the kernel is updated to upstream revision 20160831 that brings in a few bug fixes and cleanups. In particular, it is possible to mask GPEs now (and the sysfs interface for GPE control is fixed on top of that), problems related to the table loading mechanism are fixed and all code related to FADT version 2 (which has never been part of the ACPI specification) is dropped. On the new features front, there is a new watchdog driver based on the ACPI WDAT (ACPI Watchdog Action Table), needed on some platforms to replace the iTCO watchdog that doesn't work there, and some UART devices get new definitions of built-in properties (to be accessed via the generic device properties API). Also, included is a fix for an ACPI-related PCI resorces allocation issue and a few problems in the EC driver and in the button and battery drivers are fixed. In addition to that, the ACPI CPPC library is updated to make batching of requests sent over the PCC channel possible (which reduces the PCC usage overhead substantially in some cases) and to support functional fixed hardware (FFH) type of CPPC registers access (which will allow CPPC to be used on x86 too in the future). As usual, there are some assorted fixes and cleanups too. Specifics: - Update of the ACPICA code in the kernel to upstream revision 20160831 with the following major changes: * New mechanism for GPE masking. * Fixes for issues related to the LoadTable operator and table loading. * Fixes for issues related to so-called module-level code (MLC), that is AML that doesn't belong to any methods. * Change of the return value of the _OSI method to reflect the Windows behavior. * GAS (Generic Address Structure) support fix related to 32-bit FADT addresses. * Elimination of unnecessary FADT version 2 support. * ACPI tools fixes and cleanups. From Bob Moore, Lv Zheng, and Jung-uk Kim. - ACPI sysfs interface updates to fix GPE handling (on top of the new GPE masking mechanism in ACPICA) and issues related to table loading (Lv Zheng). - New watchdog driver based on the ACPI WDAT (ACPI Watchdog Action Table), needed on some platforms to replace the iTCO watchdog that doesn't work there and related updates of the intel_pmc_ipc, i2c/i801 and MFD/lcp_ich drivers (Mika Westerberg). - Driver core fix to prevent it from leaking secondary fwnode objects during device removal (Lukas Wunner). - New definitions of built-in properties for UART in ACPI-based x86 SoC drivers and a 8250_dw driver quirk for the APM X-Gene SoC (Heikki Krogerus). - New device ID for the Vulcan SPI controller and constification of local strucures in the AMD SoC (APD) ACPI driver (Kamlakant Patel, Julia Lawall). - Fix for a bug causing the allocation of PCI resorces to fail if ACPI-enumerated child platform devices are registered below the PCI devices in question (Mika Westerberg). - Change of the default polarity for PCI legacy IRQs to high on systems booting wth ACPI on platforms with a GIC interrupt controller model fixing the discrepancy between the specification and HW behavior (Lorenzo Pieralisi). - Fixes for the handling of system suspend/resume in the ACPI EC driver and update of that driver to make it cope with the cases when the EC device defined in the ECDT has to be used throughout the entire system life cycle (Lv Zheng). - Update of the ACPI CPPC library to allow it to batch requests sent over the PCC channel (to reduce overhead), to support the fixed functional hardware (FFH) CPPC registers access type, to notify the mailbox framework about TX completions when the interrupt flag is set for the PCC mailbox, and to support HW-Reduced Communication Subspace type 2 (Ashwin Chaugule, Prashanth Prakash, Srinivas Pandruvada, Hoan Tran). - ACPI button driver fix and documentation update related to the handling of laptop lids (Lv Zheng). - ACPI battery driver initialization fix (Carlos Garnacho). - ACPI GPIO enumeration documentation update (Mika Westerberg). - Assorted updates of the core ACPI bus type code (Lukas Wunner, Lv Zheng). - Assorted cleanups of the ACPI table parsing code and the x86-specific ACPI code (Al Stone). - Fixes for assorted ACPI-related issues found in linux-next (Wei Yongjun)" * tag 'acpi-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (98 commits) ACPI / documentation: Use recommended name in GPIO property names watchdog: wdat_wdt: Fix warning for using 0 as NULL watchdog: wdat_wdt: fix return value check in wdat_wdt_probe() platform/x86: intel_pmc_ipc: Do not create iTCO watchdog when WDAT table exists i2c: i801: Do not create iTCO watchdog when WDAT table exists mfd: lpc_ich: Do not create iTCO watchdog when WDAT table exists ACPI / bus: Adjust ACPI subsystem initialization for new table loading mode ACPICA: Parser: Fix a regression in LoadTable support ACPICA: Tables: Fix "UNLOAD" code path lock issues ACPI / watchdog: Add support for WDAT hardware watchdog ACPI / platform: Pay attention to parent device's resources PCI: Add pci_find_resource() ACPI / CPPC: Support PCC with interrupt flag ACPI / sysfs: Update sysfs signature handling code ACPI / sysfs: Fix an issue for LoadTable opcode ACPICA: Tables: Fix a regression in acpi_tb_find_table() ACPI / tables: Remove duplicated include from tables.c ACPI / APD: constify local structures x86: ACPI: make variable names clearer in acpi_parse_madt_lapic_entries() x86: ACPI: remove extraneous white space after semicolon ...
2016-09-16cpufreq: CPPC: Avoid overflow when calculating desired_perfHoan Tran
This patch fixes overflow issue when calculating the desired_perf. Fixes: ad38677df44b (cpufreq: CPPC: Force reporting values in KHz to fix user space interface) Signed-off-by: Hoan Tran <hotran@apm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13cpufreq: CPPC: Force reporting values in KHz to fix user space interfaceAl Stone
When CPPC is being used by ACPI on arm64, user space tools such as cpupower report CPU frequency values from sysfs that are incorrect. What the driver was doing was reporting the values given by ACPI tables in whatever scale was used to provide them. However, the ACPI spec defines the CPPC values as unitless abstract numbers. Internal kernel structures such as struct perf_cap, in contrast, expect these values to be in KHz. When these struct values get reported via sysfs, the user space tools also assume they are in KHz, causing them to report incorrect values (for example, reporting a CPU frequency of 1MHz when it should be 1.8GHz). The downside is that this approach has some assumptions: (1) It relies on SMBIOS3 being used, *and* that the Max Frequency value for a processor is set to a non-zero value. (2) It assumes that all processors run at the same speed, or that the CPPC values have all been scaled to reflect relative speed. This patch retrieves the largest CPU Max Frequency from a type 4 DMI record that it can find. This may not be an issue, however, as a sampling of DMI data on x86 and arm64 indicates there is often only one such record regardless. Since CPPC is relatively new, it is unclear if the ACPI ASL will always be written to reflect any sort of relative performance of processors of differing speeds. (3) It assumes that performance and frequency both scale linearly. For arm64 servers, this may be sufficient, but it does rely on firmware values being set correctly. Hence, other approaches will be considered in the future. This has been tested on three arm64 servers, with and without DMI, with and without CPPC support. Signed-off-by: Al Stone <ahs3@redhat.com> Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-08ACPI / CPPC: Add prefix cppc to cpudata structure nameSrinivas Pandruvada
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>
2016-08-31ACPI / CPPC: set a non-zero value for transition_latencyPrakash, Prashanth
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>
2016-04-25cpufreq: ACPI / CPPC: Add module support for cppc_cpufreq driverAshwin Chaugule
Add a function to cleanup at module exit and export appropriate GPL string to enable moduler support for the cppc_cpufreq driver. Reported-by: Srinivas Pandruvada <srinivas.pandruvada@intel.com> Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-23cpufreq: CPPC: Initialize and check CPUFreq CPU co-ord type correctlyAshwin Chaugule
The CPU policy struct indicates the co-ordination type for all CPUs of a common freq domain. Initialize it correctly using the CPU specific data gathered from CPPC ACPI lib via acpi_get_psd_map(). The PSD object is optional, so the cpu->shared_type can also be 0. So instead of assuming any value other than SW_ANY(0xFD) is unsupported, explictly check if shared_type is SW_ALL and then bail. Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-07cpufreq: CPPC: Delete an unnecessary check before the function call kfree()Markus Elfring
The kfree() function tests whether its argument is NULL and then returns immediately. Thus the test around the call is not needed. This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-12ACPI / CPPC: Add a CPUFreq driver for use with CPPCAshwin Chaugule
This driver utilizes the methods introduced in a previous patch titled - "ACPI: Introduce CPU performance controls using CPPC" and enables usage with existing CPUFreq governors. 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>