Pull driver core updates from Danilo Krummrich:
"Arch Topology:
- Move parse_acpi_topology() from arm64 to common code for reuse in
RISC-V
CPU:
- Expose housekeeping CPUs through /sys/devices/system/cpu/housekeeping
- Print a newline (or 0x0A) instead of '(null)' reading
/sys/devices/system/cpu/nohz_full when nohz_full= is not set
debugfs
- Remove (broken) 'no-mount' mode
- Remove redundant access mode checks in debugfs_get_tree() and
debugfs_create_*() functions
Devres:
- Remove unused devm_free_percpu() helper
- Move devm_alloc_percpu() from device.h to devres.h
Firmware Loader:
- Replace simple_strtol() with kstrtoint()
- Do not call cancel_store() when no upload is in progress
kernfs:
- Increase struct super_block::maxbytes to MAX_LFS_FILESIZE
- Fix a missing unwind path in __kernfs_new_node()
Misc:
- Increase the name size in struct auxiliary_device_id to 40
characters
- Replace system_unbound_wq with system_dfl_wq and add WQ_PERCPU to
alloc_workqueue()
Platform:
- Replace ERR_PTR() with IOMEM_ERR_PTR() in platform ioremap
functions
Rust:
- Auxiliary:
- Unregister auxiliary device on parent device unbind
- Move parent() to impl Device; implement device context aware
parent() for Device<Bound>
- Illustrate how to safely obtain a driver's device private data
when calling from an auxiliary driver into the parant device
driver
- DebugFs:
- Implement support for binary large objects
- Device:
- Let probe() return the driver's device private data as pinned
initializer, i.e. impl PinInit<Self, Error>
- Implement safe accessor for a driver's device private data for
Device<Bound> (returned reference can't out-live driver binding
and guarantees the correct private data type)
- Implement AsBusDevice trait, to be used by class device
abstractions to derive the bus device type of the parent device
- DMA:
- Store raw pointer of allocation as NonNull
- Use start_ptr() and start_ptr_mut() to inherit correct
mutability of self
- FS:
- Add file::Offset type alias
- I2C:
- Add abstractions for I2C device / driver infrastructure
- Implement abstractions for manual I2C device registrations
- I/O:
- Use "kernel vertical" style for imports
- Define ResourceSize as resource_size_t
- Move ResourceSize to top-level I/O module
- Add type alias for phys_addr_t
- Implement Rust version of read_poll_timeout_atomic()
- PCI:
- Use "kernel vertical" style for imports
- Move I/O and IRQ infrastructure to separate files
- Add support for PCI interrupt vectors
- Implement TryInto<IrqRequest<'a>> for IrqVector<'a> to convert
an IrqVector bound to specific pci::Device into an IrqRequest
bound to the same pci::Device's parent Device
- Leverage pin_init_scope() to get rid of redundant Result in IRQ
methods
- PinInit:
- Add {pin_}init_scope() to execute code before creating an
initializer
- Platform:
- Leverage pin_init_scope() to get rid of redundant Result in IRQ
methods
- Timekeeping:
- Implement abstraction of udelay()
- Uaccess:
- Implement read_slice_partial() and read_slice_file() for
UserSliceReader
- Implement write_slice_partial() and write_slice_file() for
UserSliceWriter
sysfs:
- Prepare the constification of struct attribute"
* tag 'driver-core-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (75 commits)
rust: pci: fix build failure when CONFIG_PCI_MSI is disabled
debugfs: Fix default access mode config check
debugfs: Remove broken no-mount mode
debugfs: Remove redundant access mode checks
driver core: Check drivers_autoprobe for all added devices
driver core: WQ_PERCPU added to alloc_workqueue users
driver core: replace use of system_unbound_wq with system_dfl_wq
tick/nohz: Expose housekeeping CPUs in sysfs
tick/nohz: avoid showing '(null)' if nohz_full= not set
sysfs/cpu: Use DEVICE_ATTR_RO for nohz_full attribute
kernfs: fix memory leak of kernfs_iattrs in __kernfs_new_node
fs/kernfs: raise sb->maxbytes to MAX_LFS_FILESIZE
mod_devicetable: Bump auxiliary_device_id name size
sysfs: simplify attribute definition macros
samples/kobject: constify 'struct foo_attribute'
samples/kobject: add is_visible() callback to attribute group
sysfs: attribute_group: enable const variants of is_visible()
sysfs: introduce __SYSFS_FUNCTION_ALTERNATIVE()
sysfs: transparently handle const pointers in ATTRIBUTE_GROUPS()
sysfs: attribute_group: allow registration of const attribute
...
Pull devicetree updates from Rob Herring:
"DT bindings:
- Convert lattice,ice40-fpga-mgr, apm,xgene-storm-dma,
brcm,sr-thermal, amazon,al-thermal, brcm,ocotp, mt8173-mdp, Actions
Owl SPS, Marvell AP80x System Controller, Marvell CP110 System
Controller, cznic,moxtet, and apm,xgene-slimpro-mbox to DT schema
format
- Add i.MX95 fsl,irqsteer, MT8365 Mali Bifrost GPU, Anvo ANV32C81W
EEPROM, and Microchip pic64gx PLIC
- Add missing LGE, AMD Seattle, and APM X-Gene SoC platform
compatibles
- Updates to brcm,bcm2836-l1-intc, brcm,bcm2835-hvs, and bcm2711-hdmi
bindings to fix warnings on BCM2712 platforms
- Drop obsolete db8500-thermal.txt
- Treewide clean-up of extra blank lines and inconsistent quoting
- Ensure all .dtbo targets are applied to a base .dtb
- Speed up dt_binding_check by skipping running validation on empty
examples
DT core:
- Add of_machine_device_match() and of_machine_get_match_data()
helpers and convert users treewide
- Fix bounds checking of address properties in FDT code. Rework the
code to have a single implementation of the bounds checks.
- Rework of_irq_init() to ignore any implicit interrupt-parent (i.e.
in a parent node) on nodes without an interrupt. This matches the
spec description and fixes some RISC-V platforms.
- Avoid a spurious message on overlay removal
- Skip DT kunit tests on RISCV+ACPI"
* tag 'devicetree-for-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (55 commits)
dt-bindings: kbuild: Skip validating empty examples
dt-bindings: interrupt-controller: brcm,bcm2836-l1-intc: Drop interrupt-controller requirement
dt-bindings: display: Fix brcm,bcm2835-hvs bindings for BCM2712
dt-bindings: display: bcm2711-hdmi: Add interrupt details for BCM2712
of: Skip devicetree kunit tests when RISCV+ACPI doesn't populate root node
soc: tegra: Simplify with of_machine_device_match()
soc: qcom: ubwc: Simplify with of_machine_get_match_data()
powercap: dtpm: Simplify with of_machine_get_match_data()
platform: surface: Simplify with of_machine_get_match_data()
irqchip/atmel-aic: Simplify with of_machine_get_match_data()
firmware: qcom: scm: Simplify with of_machine_device_match()
cpuidle: big_little: Simplify with of_machine_device_match()
cpufreq: sun50i: Simplify with of_machine_device_match()
cpufreq: mediatek: Simplify with of_machine_get_match_data()
cpufreq: dt-platdev: Simplify with of_machine_get_match_data()
of: Add wrappers to match root node with OF device ID tables
dt-bindings: eeprom: at25: Add Anvo ANV32C81W
of/reserved_mem: Simplify the logic of __reserved_mem_alloc_size()
of/reserved_mem: Simplify the logic of fdt_scan_reserved_mem_reg_nodes()
of/reserved_mem: Simplify the logic of __reserved_mem_reserve_reg()
...
Pull CPUFreq updates for 6.19 from Viresh Kumar:
"- tegra186: Add OPP / bandwidth support for Tegra186 (Aaron Kling).
- Minor improvements to various cpufreq drivers (Christian Marangi, Hal
Feng, Jie Zhan, Marco Crivellari, Miaoqian Lin, and Shuhao Fu)."
* tag 'cpufreq-arm-updates-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm:
cpufreq: qcom-nvmem: fix compilation warning for qcom_cpufreq_ipq806x_match_list
cpufreq: tegra194: add WQ_PERCPU to alloc_workqueue users
cpufreq: qcom-nvmem: add compatible fallback for ipq806x for no SMEM
cpufreq: CPPC: Don't warn if FIE init fails to read counters
cpufreq: nforce2: fix reference count leak in nforce2
cpufreq: tegra186: add OPP support and set bandwidth
cpufreq: dt-platdev: Add JH7110S SOC to the allowlist
cpufreq: s5pv210: fix refcount leak
If CONFIG_OF is not enabled, of_match_node() is set as NULL and
qcom_cpufreq_ipq806x_match_list won't be used causing a compilation
warning.
Flag qcom_cpufreq_ipq806x_match_list as __maybe_unused to fix the
compilation warning.
While at it also flag as __initconst as it's used only in probe contest
and can be freed after probe.
This follows the pattern of the usual of_device_id variables.
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202511202119.6zvvFMup-lkp@intel.com/
Fixes: 58f5d39d5e ("cpufreq: qcom-nvmem: add compatible fallback for ipq806x for no SMEM")
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
[ Viresh: Drop __initconst ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Pull amd-pstate content for 6.19 (11/10/25) from Mario Liminciello:
"* optimizations for parameter array handling
* fix for mode changes with offline CPUs"
* tag 'amd-pstate-v6.19-2025-11-10' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/superm1/linux:
cpufreq/amd-pstate: Call cppc_set_auto_sel() only for online CPUs
cpufreq/amd-pstate: Add static asserts for EPP indices
cpufreq/amd-pstate: Fix some whitespace issues
cpufreq/amd-pstate: Adjust return values in amd_pstate_update_status()
cpufreq/amd-pstate: Make amd_pstate_get_mode_string() never return NULL
cpufreq/amd-pstate: Drop NULL value from amd_pstate_mode_string
cpufreq/amd-pstate: Use sysfs_match_string() for epp
Commit ac4e04d9e3 ("cpufreq: intel_pstate: Unchecked MSR aceess in
legacy mode") introduced a check for feature X86_FEATURE_IDA to verify
turbo mode support. Although this is the correct way to check for turbo
mode support, it causes issues on some platforms that disable turbo
during OS boot, but enable it later [1]. Before adding this feature
check, users were able to get turbo mode frequencies by writing 0 to
/sys/devices/system/cpu/intel_pstate/no_turbo post-boot.
To restore the old behavior on the affected systems while still
addressing the unchecked MSR issue on some Skylake-X systems, check
X86_FEATURE_IDA only immediately before updates of MSR_IA32_PERF_CTL
that may involve setting the Turbo Engage Bit (bit 32).
Fixes: ac4e04d9e3 ("cpufreq: intel_pstate: Unchecked MSR aceess in legacy mode")
Reported-by: Aaron Rainbolt <arainbolt@kfocus.org>
Closes: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2122531 [1]
Tested-by: Aaron Rainbolt <arainbolt@kfocus.org>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
[ rjw: Subject adjustment, changelog edits ]
Link: https://patch.msgid.link/20251111010840.141490-1-srinivas.pandruvada@linux.intel.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
amd_pstate_change_mode_without_dvr_change() calls cppc_set_auto_sel()
for all the present CPUs.
However, this callpath eventually calls cppc_set_reg_val() which
accesses the per-cpu cpc_desc_ptr object. This object is initialized
only for online CPUs via acpi_soft_cpu_online() -->
__acpi_processor_start() --> acpi_cppc_processor_probe().
Hence, restrict calling cppc_set_auto_sel() to only the online CPUs.
Fixes: 3ca7bc818d ("cpufreq: amd-pstate: Add guided mode control support via sysfs")
Suggested-by: Mario Limonciello (AMD) (kernel.org) <superm1@kernel.org>
Signed-off-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
In case a new index is introduced add a static assert to make sure
that strings and values are updated.
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
Add whitespace around the equals and remove leading space.
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
get_mode_idx_from_str() already checks the upper boundary for a string
sent. Drop the extra check in amd_pstate_update_status() and pass
the return code if there is a failure.
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
amd_pstate_get_mode_string() is only used by amd-pstate-ut. Set the
failure path to use AMD_PSTATE_UNDEFINED ("undefined") to avoid showing
"(null)" as a string when running test suite.
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
None of the users actually look for the NULL value. To avoid risk
of regression introducing a new value but forgetting to add a string
add a static assert to test AMD_PSTATE_MAX matches the array size.
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
Rather than scanning the buffer and manually matching the string
use the sysfs macros.
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
Currently if a user enqueues a work item using schedule_delayed_work() the
used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use
WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to
schedule_work() that is using system_wq and queue_work(), that makes use
again of WORK_CPU_UNBOUND.
This lack of consistency cannot be addressed without refactoring the API.
alloc_workqueue() treats all queues as per-CPU by default, while unbound
workqueues must opt-in via WQ_UNBOUND.
This default is suboptimal: most workloads benefit from unbound queues,
allowing the scheduler to place worker threads where they’re needed and
reducing noise when CPUs are isolated.
This continues the effort to refactor workqueue APIs, which began with
the introduction of new workqueues and a new alloc_workqueue flag in:
commit 128ea9f6cc ("workqueue: Add system_percpu_wq and system_dfl_wq")
commit 930c2ea566 ("workqueue: Add new WQ_PERCPU flag")
This change adds a new WQ_PERCPU flag to explicitly request
alloc_workqueue() to be per-cpu when WQ_UNBOUND has not been specified.
With the introduction of the WQ_PERCPU flag (equivalent to !WQ_UNBOUND),
any alloc_workqueue() caller that doesn’t explicitly specify WQ_UNBOUND
must now use WQ_PERCPU.
Once migration is complete, WQ_UNBOUND can be removed and unbound will
become the implicit default.
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
[ Viresh: Fixed Subject ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
On some IPQ806x SoC SMEM might be not initialized by SBL. This is the
case for some Google devices (the OnHub family) that can't make use of
SMEM to detect the SoC ID (and socinfo can't be used either as it does
depends on SMEM presence).
To handle these specific case, check if the SMEM is not initialized (by
checking if the qcom_smem_get_soc_id returns -ENODEV) and fallback to
OF machine compatible checking to identify the SoC variant.
Suggested-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
During the CPPC FIE initialization, reading perf counters on offline cpus
should be expected to fail. Don't warn on this case.
Also, change the error log level to debug since FIE is optional.
Co-developed-by: Bowen Yu <yubowen8@huawei.com>
Signed-off-by: Bowen Yu <yubowen8@huawei.com> # Changing loglevel to debug
Signed-off-by: Jie Zhan <zhanjie9@hisilicon.com>
[ Viresh: Added back the dropped comment. ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
There are two reference count leaks in this driver:
1. In nforce2_fsb_read(): pci_get_subsys() increases the reference count
of the PCI device, but pci_dev_put() is never called to release it,
thus leaking the reference.
2. In nforce2_detect_chipset(): pci_get_subsys() gets a reference to the
nforce2_dev which is stored in a global variable, but the reference
is never released when the module is unloaded.
Fix both by:
- Adding pci_dev_put(nforce2_sub5) in nforce2_fsb_read() after reading
the configuration.
- Adding pci_dev_put(nforce2_dev) in nforce2_exit() to release the
global device reference.
Found via static analysis.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Add support to use OPP table from DT in Tegra186 cpufreq driver.
Tegra SoC's receive the frequency lookup table (LUT) from BPMP-FW.
Cross check the OPP's present in DT against the LUT from BPMP-FW
and enable only those DT OPP's which are present in LUT also.
The OPP table in DT has CPU Frequency to bandwidth mapping where
the bandwidth value is per MC channel. DRAM bandwidth depends on the
number of MC channels which can vary as per the boot configuration.
This per channel bandwidth from OPP table will be later converted by
MC driver to final bandwidth value by multiplying with number of
channels before being handled in the EMC driver.
If OPP table is not present in DT, then use the LUT from BPMP-FW
directly as the CPU frequency table and not do the DRAM frequency
scaling which is same as the current behavior.
Signed-off-by: Aaron Kling <webgeek1234@gmail.com>
[ Viresh: Fix _free() definitions ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
In function `s5pv210_cpu_init`, a possible refcount inconsistency has
been identified, causing a resource leak.
Why it is a bug:
1. For every clk_get, there should be a matching clk_put on every
successive error handling path.
2. After calling `clk_get(dmc1_clk)`, variable `dmc1_clk` will not be
freed even if any error happens.
How it is fixed: For every failed path, an extra goto label is added to
ensure `dmc1_clk` will be freed regardlessly.
Signed-off-by: Shuhao Fu <sfual@cse.ust.hk>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
The driver model defines the lifetime of the private data stored in (and
owned by) a bus device to be valid from when the driver is bound to a
device (i.e. from successful probe()) until the driver is unbound from
the device.
This is already taken care of by the Rust implementation of the driver
model. However, we still ask drivers to return a Result<Pin<KBox<Self>>>
from probe().
Unlike in C, where we do not have the concept of initializers, but
rather deal with uninitialized memory, drivers can just return an
impl PinInit<Self, Error> instead.
This contributes to more clarity to the fact that a driver returns it's
device private data in probe() and the Rust driver model owns the data,
manages the lifetime and - considering the lifetime - provides (safe)
accessors for the driver.
Hence, let probe() functions return an impl PinInit<Self, Error> instead
of Result<Pin<KBox<Self>>>.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Some debug messages generated by intel_pstate on a given hybrid system
are only printed for some CPUs which is confusing, so modify the driver
to print them for all CPUs. Also change those messages to avoid
printing local variable names in them.
Moreover, some debug messages printed by intel_pstate are quite hard
to understand without looking at the code printing them, so make them
somewhat clearer while at it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/8609836.T7Z3S40VBb@rafael.j.wysocki
Instead of using HWP-to-frequency scaling factors for computing cost
coefficients in the energy model used on hybrid systems, which is
fragile, rely on CPU type information that is easily accessible now and
the information on whether or not L3 cache is present for this purpose.
This also allows the cost coefficients for P-cores to be adjusted so
that they start to be populated somewhat earlier (that is, before
E-cores are loaded up to their full capacity).
In addition to the above, replace an inaccurate comment regarding the
reason why the freq value is added to the cost in hybrid_get_cost().
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Reviewed-by: Yaxiong Tian <tianyaxiong@kylinos.cn>
Link: https://patch.msgid.link/5932894.DvuYhMxLoT@rafael.j.wysocki
During S3/S4 suspend and resume, cpufreq policies are not freed or
recreated; the freq_table and policy structure remain intact. However,
set_freq_table_sorted() currently resets policy->freq_table_sorted to
UNSORTED unconditionally, which is unnecessary since the table order
does not change across suspend/resume.
This patch adds a check to skip validation if policy->freq_table_sorted
is already ASCENDING or DESCENDING. This avoids unnecessary traversal
of the frequency table on S3/S4 resume or repeated online events,
reducing overhead while preserving correctness.
Signed-off-by: Zihuan Zhang <zhangzihuan@kylinos.cn>
Link: https://patch.msgid.link/20251011072420.11495-1-zhangzihuan@kylinos.cn
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
After resuming from S4, all CPUs except the boot CPU have the wrong EPP
hint programmed. This is because when the CPUs were offlined the EPP value
was reset to 0.
This is a similar problem as fixed by
commit ba3319e590 ("cpufreq/amd-pstate: Fix a regression leading to EPP
0 after resume") and the solution is also similar. When offlining rather
than reset the values to zero, reset them to match those chosen by the
policy. When the CPUs are onlined again these values will be restored.
Closes: https://community.frame.work/t/increased-power-usage-after-resuming-from-suspend-on-ryzen-7040-kernel-6-15-regression/74531/20?u=mario_limonciello
Fixes: 608a76b652 ("cpufreq/amd-pstate: Add support for the "Requested CPU Min frequency" BIOS option")
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
Merge CPUFreq fixes for 6.18 from Viresh Kumar:
"- Update frequency for all tegra CPUs (Aaron Kling).
- Fix device leak in mediatek driver (Johan Hovold).
- Rust cpufreq helper cleanup (Thorsten Blum)."
* tag 'cpufreq-arm-updates-6.18-rc' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm:
cpufreq: tegra186: Initialize all cores to max frequencies
cpufreq: tegra186: Set target frequency for all cpus in policy
rust: cpufreq: streamline find_supply_names
cpufreq: mediatek: fix device leak on probe failure
Instead of using CPUFREQ_ETERNAL for signaling an error condition
in cppc_get_transition_latency(), change the return value type of
that function to int and make it return a proper negative error
code on failures.
No intentional functional impact.
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Reviewed-by: Jie Zhan <zhanjie9@hisilicon.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Qais Yousef <qyousef@layalina.io>
If cppc_get_transition_latency() returns CPUFREQ_ETERNAL to indicate a
failure to retrieve the transition latency value from the platform
firmware, the CPPC cpufreq driver will use that value (converted to
microseconds) as the policy transition delay, but it is way too large
for any practical use.
Address this by making the driver use the cpufreq's default
transition latency value (in microseconds) as the transition delay
if CPUFREQ_ETERNAL is returned by cppc_get_transition_latency().
Fixes: d4f3388afd ("cpufreq / CPPC: Set platform specific transition_delay_us")
Cc: 5.19+ <stable@vger.kernel.org> # 5.19
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Reviewed-by: Jie Zhan <zhanjie9@hisilicon.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Qais Yousef <qyousef@layalina.io>
Commit a755d0e2d4 ("cpufreq: Honour transition_latency over
transition_delay_us") caused platforms where cpuinfo.transition_latency
is CPUFREQ_ETERNAL to get a very large transition latency whereas
previously it had been capped at 10 ms (and later at 2 ms).
This led to a user-observable regression between 6.6 and 6.12 as
described by Shawn:
"The dbs sampling_rate was 10000 us on 6.6 and suddently becomes
6442450 us (4294967295 / 1000 * 1.5) on 6.12 for these platforms
because the default transition delay was dropped [...].
It slows down dbs governor's reacting to CPU loading change
dramatically. Also, as transition_delay_us is used by schedutil
governor as rate_limit_us, it shows a negative impact on device
idle power consumption, because the device gets slightly less time
in the lowest OPP."
Evidently, the expectation of the drivers using CPUFREQ_ETERNAL as
cpuinfo.transition_latency was that it would be capped by the core,
but they may as well return a default transition latency value instead
of CPUFREQ_ETERNAL and the core need not do anything with it.
Accordingly, introduce CPUFREQ_DEFAULT_TRANSITION_LATENCY_NS and make
all of the drivers in question use it instead of CPUFREQ_ETERNAL. Also
update the related Rust binding.
Fixes: a755d0e2d4 ("cpufreq: Honour transition_latency over transition_delay_us")
Closes: https://lore.kernel.org/linux-pm/20250922125929.453444-1-shawnguo2@yeah.net/
Reported-by: Shawn Guo <shawnguo@kernel.org>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Reviewed-by: Jie Zhan <zhanjie9@hisilicon.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 6.6+ <stable@vger.kernel.org> # 6.6+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/2264949.irdbgypaU6@rafael.j.wysocki
[ rjw: Fix typo in new symbol name, drop redundant type cast from Rust binding ]
Tested-by: Shawn Guo <shawnguo@kernel.org> # with cpufreq-dt driver
Reviewed-by: Qais Yousef <qyousef@layalina.io>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
During initialization, the EDVD_COREx_VOLT_FREQ registers for some cores
are still at reset values and not reflecting the actual frequency. This
causes get calls to fail. Set all cores to their respective max
frequency during probe to initialize the registers to working values.
Suggested-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Aaron Kling <webgeek1234@gmail.com>
Reviewed-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
The original commit set all cores in a cluster to a shared policy, but
did not update set_target to apply a frequency change to all cores for
the policy. This caused most cores to remain stuck at their boot
frequency.
Fixes: be4ae8c194 ("cpufreq: tegra186: Share policy per cluster")
Signed-off-by: Aaron Kling <webgeek1234@gmail.com>
Reviewed-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Remove local variables from find_supply_names() and use .and_then() with
the more concise kernel::kvec![] macro, instead of KVec::with_capacity()
followed by .push() and Some().
No functional changes intended.
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
The cpufreq documentation suggests avoiding direct pointer subtraction
when working with entries in driver_freq_table, as it is relatively
costly. Instead, the recommended approach is to use the provided
iteration macros, like cpufreq_for_each_valid_entry_idx().
Use cpufreq_for_each_entry_idx() instead of pointer subtraction in
cpufreq_frequency_table_cpuinfo() which improves code clarity and
follows the established cpufreq coding style.
While at it, remove redundant local variable initialization from
cpufreq_table_index_unsorted().
No functional change intended.
Signed-off-by: Zihuan Zhang <zhangzihuan@kylinos.cn>
Link: https://patch.msgid.link/20250923075553.45532-1-zhangzihuan@kylinos.cn
[ rjw: Subject tweak, changelog edits, local variable definition tweak ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
commit 2a6c727387 ("cpufreq: Initialize cpufreq-based
frequency-invariance later") postponed the frequency invariance
initialization to avoid disabling it in the error case.
This isn't locking safe, instead move the initialization up before
the subsys interface is registered (which will rebuild the
sched_domains) and add the corresponding disable on the error path.
Observed lockdep without this patch:
[ 0.989686] ======================================================
[ 0.989688] WARNING: possible circular locking dependency detected
[ 0.989690] 6.17.0-rc4-cix-build+ #31 Tainted: G S
[ 0.989691] ------------------------------------------------------
[ 0.989692] swapper/0/1 is trying to acquire lock:
[ 0.989693] ffff800082ada7f8 (sched_energy_mutex){+.+.}-{4:4}, at: rebuild_sched_domains_energy+0x30/0x58
[ 0.989705]
but task is already holding lock:
[ 0.989706] ffff000088c89bc8 (&policy->rwsem){+.+.}-{4:4}, at: cpufreq_online+0x7f8/0xbe0
[ 0.989713]
which lock already depends on the new lock.
Fixes: 2a6c727387 ("cpufreq: Initialize cpufreq-based frequency-invariance later")
Signed-off-by: Christian Loehle <christian.loehle@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The comment above the condition `if (cpu->last_sample_time)` clearly
indicates that the branch is taken for the vast majority of invocations
after the first sample in a cycle. The first sample is a one-time
initialization case.
Add likely() hint to the condition to improve branch prediction for
this performance-critical path in intel_pstate_sample().
Signed-off-by: Yaxiong Tian <tianyaxiong@kylinos.cn>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
