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11 hoursMerge tag 'rust-6.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux Pull Rust updates from Miguel Ojeda: "Toolchain and infrastructure: - Enable a set of Clippy lints: 'ptr_as_ptr', 'ptr_cast_constness', 'as_ptr_cast_mut', 'as_underscore', 'cast_lossless' and 'ref_as_ptr' These are intended to avoid type casts with the 'as' operator, which are quite powerful, into restricted variants that are less powerful and thus should help to avoid mistakes - Remove the 'author' key now that most instances were moved to the plural one in the previous cycle 'kernel' crate: - New 'bug' module: add 'warn_on!' macro which reuses the existing 'BUG'/'WARN' infrastructure, i.e. it respects the usual sysctls and kernel parameters: warn_on!(value == 42); To avoid duplicating the assembly code, the same strategy is followed as for the static branch code in order to share the assembly between both C and Rust This required a few rearrangements on C arch headers -- the existing C macros should still generate the same outputs, thus no functional change expected there - 'workqueue' module: add delayed work items, including a 'DelayedWork' struct, a 'impl_has_delayed_work!' macro and an 'enqueue_delayed' method, e.g.: /// Enqueue the struct for execution on the system workqueue, /// where its value will be printed 42 jiffies later. fn print_later(value: Arc<MyStruct>) { let _ = workqueue::system().enqueue_delayed(value, 42); } - New 'bits' module: add support for 'bit' and 'genmask' functions, with runtime- and compile-time variants, e.g.: static_assert!(0b00010000 == bit_u8(4)); static_assert!(0b00011110 == genmask_u8(1..=4)); assert!(checked_bit_u32(u32::BITS).is_none()); - 'uaccess' module: add 'UserSliceReader::strcpy_into_buf', which reads NUL-terminated strings from userspace into a '&CStr' Introduce 'UserPtr' newtype, similar in purpose to '__user' in C, to minimize mistakes handling userspace pointers, including mixing them up with integers and leaking them via the 'Debug' trait. Add it to the prelude, too - Start preparations for the replacement of our custom 'CStr' type with the analogous type in the 'core' standard library. This will take place across several cycles to make it easier. For this one, it includes a new 'fmt' module, using upstream method names and some other cleanups Replace 'fmt!' with a re-export, which helps Clippy lint properly, and clean up the found 'uninlined-format-args' instances - 'dma' module: - Clarify wording and be consistent in 'coherent' nomenclature - Convert the 'read!()' and 'write!()' macros to return a 'Result' - Add 'as_slice()', 'write()' methods in 'CoherentAllocation' - Expose 'count()' and 'size()' in 'CoherentAllocation' and add the corresponding type invariants - Implement 'CoherentAllocation::dma_handle_with_offset()' - 'time' module: - Make 'Instant' generic over clock source. This allows the compiler to assert that arithmetic expressions involving the 'Instant' use 'Instants' based on the same clock source - Make 'HrTimer' generic over the timer mode. 'HrTimer' timers take a 'Duration' or an 'Instant' when setting the expiry time, depending on the timer mode. With this change, the compiler can check the type matches the timer mode - Add an abstraction for 'fsleep'. 'fsleep' is a flexible sleep function that will select an appropriate sleep method depending on the requested sleep time - Avoid 64-bit divisions on 32-bit hardware when calculating timestamps - Seal the 'HrTimerMode' trait. This prevents users of the 'HrTimerMode' from implementing the trait on their own types - Pass the correct timer mode ID to 'hrtimer_start_range_ns()' - 'list' module: remove 'OFFSET' constants, allowing to remove pointer arithmetic; now 'impl_list_item!' invokes 'impl_has_list_links!' or 'impl_has_list_links_self_ptr!'. Other simplifications too - 'types' module: remove 'ForeignOwnable::PointedTo' in favor of a constant, which avoids exposing the type of the opaque pointer, and require 'into_foreign' to return non-null Remove the 'Either<L, R>' type as well. It is unused, and we want to encourage the use of custom enums for concrete use cases - 'sync' module: implement 'Borrow' and 'BorrowMut' for 'Arc' types to allow them to be used in generic APIs - 'alloc' module: implement 'Borrow' and 'BorrowMut' for 'Box<T, A>'; and 'Borrow', 'BorrowMut' and 'Default' for 'Vec<T, A>' - 'Opaque' type: add 'cast_from' method to perform a restricted cast that cannot change the inner type and use it in callers of 'container_of!'. Rename 'raw_get' to 'cast_into' to match it - 'rbtree' module: add 'is_empty' method - 'sync' module: new 'aref' submodule to hold 'AlwaysRefCounted' and 'ARef', which are moved from the too general 'types' module which we want to reduce or eventually remove. Also fix a safety comment in 'static_lock_class' 'pin-init' crate: - Add 'impl<T, E> [Pin]Init<T, E> for Result<T, E>', so results are now (pin-)initializers - Add 'Zeroable::init_zeroed()' that delegates to 'init_zeroed()' - New 'zeroed()', a safe version of 'mem::zeroed()' and also provide it via 'Zeroable::zeroed()' - Implement 'Zeroable' for 'Option<&T>', 'Option<&mut T>' and for 'Option<[unsafe] [extern "abi"] fn(...args...) -> ret>' for '"Rust"' and '"C"' ABIs and up to 20 arguments - Changed blanket impls of 'Init' and 'PinInit' from 'impl<T, E> [Pin]Init<T, E> for T' to 'impl<T> [Pin]Init<T> for T' - Renamed 'zeroed()' to 'init_zeroed()' - Upstream dev news: improve CI more to deny warnings, use '--all-targets'. Check the synchronization status of the two '-next' branches in upstream and the kernel MAINTAINERS: - Add Vlastimil Babka, Liam R. Howlett, Uladzislau Rezki and Lorenzo Stoakes as reviewers (thanks everyone) And a few other cleanups and improvements" * tag 'rust-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (76 commits) rust: Add warn_on macro arm64/bug: Add ARCH_WARN_ASM macro for BUG/WARN asm code sharing with Rust riscv/bug: Add ARCH_WARN_ASM macro for BUG/WARN asm code sharing with Rust x86/bug: Add ARCH_WARN_ASM macro for BUG/WARN asm code sharing with Rust rust: kernel: move ARef and AlwaysRefCounted to sync::aref rust: sync: fix safety comment for `static_lock_class` rust: types: remove `Either<L, R>` rust: kernel: use `core::ffi::CStr` method names rust: str: add `CStr` methods matching `core::ffi::CStr` rust: str: remove unnecessary qualification rust: use `kernel::{fmt,prelude::fmt!}` rust: kernel: add `fmt` module rust: kernel: remove `fmt!`, fix clippy::uninlined-format-args scripts: rust: emit path candidates in panic message scripts: rust: replace length checks with match rust: list: remove nonexistent generic parameter in link rust: bits: add support for bits/genmask macros rust: list: remove OFFSET constants rust: list: add `impl_list_item!` examples rust: list: use fully qualified path ...
6 daysMerge tag 'driver-core-6.17-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core Pull driver core updates from Danilo Krummrich: "debugfs: - Remove unneeded debugfs_file_{get,put}() instances - Remove last remnants of debugfs_real_fops() - Allow storing non-const void * in struct debugfs_inode_info::aux sysfs: - Switch back to attribute_group::bin_attrs (treewide) - Switch back to bin_attribute::read()/write() (treewide) - Constify internal references to 'struct bin_attribute' Support cache-ids for device-tree systems: - Add arch hook arch_compact_of_hwid() - Use arch_compact_of_hwid() to compact MPIDR values on arm64 Rust: - Device: - Introduce CoreInternal device context (for bus internal methods) - Provide generic drvdata accessors for bus devices - Provide Driver::unbind() callbacks - Use the infrastructure above for auxiliary, PCI and platform - Implement Device::as_bound() - Rename Device::as_ref() to Device::from_raw() (treewide) - Implement fwnode and device property abstractions - Implement example usage in the Rust platform sample driver - Devres: - Remove the inner reference count (Arc) and use pin-init instead - Replace Devres::new_foreign_owned() with devres::register() - Require T to be Send in Devres<T> - Initialize the data kept inside a Devres last - Provide an accessor for the Devres associated Device - Device ID: - Add support for ACPI device IDs and driver match tables - Split up generic device ID infrastructure - Use generic device ID infrastructure in net::phy - DMA: - Implement the dma::Device trait - Add DMA mask accessors to dma::Device - Implement dma::Device for PCI and platform devices - Use DMA masks from the DMA sample module - I/O: - Implement abstraction for resource regions (struct resource) - Implement resource-based ioremap() abstractions - Provide platform device accessors for I/O (remap) requests - Misc: - Support fallible PinInit types in Revocable - Implement Wrapper<T> for Opaque<T> - Merge pin-init blanket dependencies (for Devres) Misc: - Fix OF node leak in auxiliary_device_create() - Use util macros in device property iterators - Improve kobject sample code - Add device_link_test() for testing device link flags - Fix typo in Documentation/ABI/testing/sysfs-kernel-address_bits - Hint to prefer container_of_const() over container_of()" * tag 'driver-core-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (84 commits) rust: io: fix broken intra-doc links to `platform::Device` rust: io: fix broken intra-doc link to missing `flags` module rust: io: mem: enable IoRequest doc-tests rust: platform: add resource accessors rust: io: mem: add a generic iomem abstraction rust: io: add resource abstraction rust: samples: dma: set DMA mask rust: platform: implement the `dma::Device` trait rust: pci: implement the `dma::Device` trait rust: dma: add DMA addressing capabilities rust: dma: implement `dma::Device` trait rust: net::phy Change module_phy_driver macro to use module_device_table macro rust: net::phy represent DeviceId as transparent wrapper over mdio_device_id rust: device_id: split out index support into a separate trait device: rust: rename Device::as_ref() to Device::from_raw() arm64: cacheinfo: Provide helper to compress MPIDR value into u32 cacheinfo: Add arch hook to compress CPU h/w id into 32 bits for cache-id cacheinfo: Set cache 'id' based on DT data container_of: Document container_of() is not to be used in new code driver core: auxiliary bus: fix OF node leak ...
2025-06-28rust: devres: replace Devres::new_foreign_owned()Danilo Krummrich
Replace Devres::new_foreign_owned() with devres::register(). The current implementation of Devres::new_foreign_owned() creates a full Devres container instance, including the internal Revocable and completion. However, none of that is necessary for the intended use of giving full ownership of an object to devres and getting it dropped once the given device is unbound. Hence, implement devres::register(), which is limited to consume the given data, wrap it in a KBox and drop the KBox once the given device is unbound, without any other synchronization. Cc: Dave Airlie <airlied@redhat.com> Cc: Simona Vetter <simona.vetter@ffwll.ch> Cc: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Benno Lossin <lossin@kernel.org> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20250626200054.243480-3-dakr@kernel.org Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-06-24rust: Use consistent "# Examples" heading style in rustdocViresh Kumar
Use a consistent `# Examples` heading in rustdoc across the codebase. Some modules previously used `## Examples` (even when they should be available as top-level headers), while others used `# Example`, which deviates from the preferred `# Examples` style. Suggested-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Benno Lossin <lossin@kernel.org> Link: https://lore.kernel.org/r/ddd5ce0ac20c99a72a4f1e4322d3de3911056922.1749545815.git.viresh.kumar@linaro.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-06-23rust: cpufreq: use c_ types from kernel preludeAbhinav Ananthu
Update cpufreq FFI callback signatures to use `c_int` from the `kernel::prelude`, rather than accessing it explicitly through `kernel::ffi::c_int`. Although these types are defined in the `ffi` crate, they are re-exported via `kernel::prelude`. This aligns with the Rust-for-Linux coding guidelines and ensures proper C ABI compatibility across platforms. Signed-off-by: Abhinav Ananthu <abhinav.ogl@gmail.com> Suggested-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Alice Ryhl <aliceryhl@google.com> [ Viresh: Fixed rustfmtcheck errors ] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2025-06-22rust: enable `clippy::ptr_as_ptr` lintTamir Duberstein
In Rust 1.51.0, Clippy introduced the `ptr_as_ptr` lint [1]: > Though `as` casts between raw pointers are not terrible, > `pointer::cast` is safer because it cannot accidentally change the > pointer's mutability, nor cast the pointer to other types like `usize`. There are a few classes of changes required: - Modules generated by bindgen are marked `#[allow(clippy::ptr_as_ptr)]`. - Inferred casts (` as _`) are replaced with `.cast()`. - Ascribed casts (` as *... T`) are replaced with `.cast::<T>()`. - Multistep casts from references (` as *const _ as *const T`) are replaced with `core::ptr::from_ref(&x).cast()` with or without `::<T>` according to the previous rules. The `core::ptr::from_ref` call is required because `(x as *const _).cast::<T>()` results in inference failure. - Native literal C strings are replaced with `c_str!().as_char_ptr()`. - `*mut *mut T as _` is replaced with `let *mut *const T = (*mut *mut T)`.cast();` since pointer to pointer can be confusing. Apply these changes and enable the lint -- no functional change intended. Link: https://rust-lang.github.io/rust-clippy/master/index.html#ptr_as_ptr [1] Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Tamir Duberstein <tamird@gmail.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Danilo Krummrich <dakr@kernel.org> Link: https://lore.kernel.org/r/20250615-ptr-as-ptr-v12-1-f43b024581e8@gmail.com [ Added `.cast()` for `opp`. - Miguel ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-06-19rust: cpufreq: Ensure C ABI compatibility in all unsafeAbhinav Ananthu
Update all `unsafe extern "C"` callback functions in the cpufreq module to use `kernel::ffi` types (`c_int`, `c_uint`, etc.) instead of Rust-native types like `i32`, `u32`, or `usize`. This change ensures that all Rust callbacks have signatures that are ABI-compatible with their corresponding C counterparts, which is critical for FFI correctness and safety. Suggested-by: Miguel Ojeda <ojeda@kernel.org> Link: https://github.com/Rust-for-Linux/linux/issues/1170 Signed-off-by: Abhinav Ananthu <abhinav.ogl@gmail.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2025-06-12rust: Use CpuId in place of raw CPU numbersViresh Kumar
Use the newly defined `CpuId` abstraction instead of raw CPU numbers. This also fixes a doctest failure for configurations where `nr_cpu_ids < 4`. The C `cpumask_{set|clear}_cpu()` APIs emit a warning when given an invalid CPU number — but only if `CONFIG_DEBUG_PER_CPU_MAPS=y` is set. Meanwhile, `cpumask_weight()` only considers CPUs up to `nr_cpu_ids`, which can cause inconsistencies: a CPU number greater than `nr_cpu_ids` may be set in the mask, yet the weight calculation won't reflect it. This leads to doctest failures when `nr_cpu_ids < 4`, as the test tries to set CPUs 2 and 3: rust_doctest_kernel_cpumask_rs_0.location: rust/kernel/cpumask.rs:180 rust_doctest_kernel_cpumask_rs_0: ASSERTION FAILED at rust/kernel/cpumask.rs:190 Fixes: 8961b8cb3099 ("rust: cpumask: Add initial abstractions") Reported-by: Miguel Ojeda <ojeda@kernel.org> Closes: https://lore.kernel.org/rust-for-linux/CANiq72k3ozKkLMinTLQwvkyg9K=BeRxs1oYZSKhJHY-veEyZdg@mail.gmail.com/ Reported-by: Andreas Hindborg <a.hindborg@kernel.org> Closes: https://lore.kernel.org/all/87qzzy3ric.fsf@kernel.org/ Suggested-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
2025-06-10cpufreq: Convert `/// SAFETY` lines to `# Safety` sectionsViresh Kumar
Replace `/// SAFETY` comments in doc comments with proper `# Safety` sections, as per rustdoc conventions. Also mark the C FFI callbacks as `unsafe` to correctly reflect their safety requirements. Reported-by: Miguel Ojeda <ojeda@kernel.org> Closes: https://github.com/Rust-for-Linux/linux/issues/1169 Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2025-06-04Merge tag 'rust-6.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux Pull Rust updates from Miguel Ojeda: "Toolchain and infrastructure: - KUnit '#[test]'s: - Support KUnit-mapped 'assert!' macros. The support that landed last cycle was very basic, and the 'assert!' macros panicked since they were the standard library ones. Now, they are mapped to the KUnit ones in a similar way to how is done for doctests, reusing the infrastructure there. With this, a failing test like: #[test] fn my_first_test() { assert_eq!(42, 43); } will report: # my_first_test: ASSERTION FAILED at rust/kernel/lib.rs:251 Expected 42 == 43 to be true, but is false # my_first_test.speed: normal not ok 1 my_first_test - Support tests with checked 'Result' return types. The return value of test functions that return a 'Result' will be checked, thus one can now easily catch errors when e.g. using the '?' operator in tests. With this, a failing test like: #[test] fn my_test() -> Result { f()?; Ok(()) } will report: # my_test: ASSERTION FAILED at rust/kernel/lib.rs:321 Expected is_test_result_ok(my_test()) to be true, but is false # my_test.speed: normal not ok 1 my_test - Add 'kunit_tests' to the prelude. - Clarify the remaining language unstable features in use. - Compile 'core' with edition 2024 for Rust >= 1.87. - Workaround 'bindgen' issue with forward references to 'enum' types. - objtool: relax slice condition to cover more 'noreturn' functions. - Use absolute paths in macros referencing 'core' and 'kernel' crates. - Skip '-mno-fdpic' flag for bindgen in GCC 32-bit arm builds. - Clean some 'doc_markdown' lint hits -- we may enable it later on. 'kernel' crate: - 'alloc' module: - 'Box': support for type coercion, e.g. 'Box<T>' to 'Box<dyn U>' if 'T' implements 'U'. - 'Vec': implement new methods (prerequisites for nova-core and binder): 'truncate', 'resize', 'clear', 'pop', 'push_within_capacity' (with new error type 'PushError'), 'drain_all', 'retain', 'remove' (with new error type 'RemoveError'), insert_within_capacity' (with new error type 'InsertError'). In addition, simplify 'push' using 'spare_capacity_mut', split 'set_len' into 'inc_len' and 'dec_len', add type invariant 'len <= capacity' and simplify 'truncate' using 'dec_len'. - 'time' module: - Morph the Rust hrtimer subsystem into the Rust timekeeping subsystem, covering delay, sleep, timekeeping, timers. This new subsystem has all the relevant timekeeping C maintainers listed in the entry. - Replace 'Ktime' with 'Delta' and 'Instant' types to represent a duration of time and a point in time. - Temporarily add 'Ktime' to 'hrtimer' module to allow 'hrtimer' to delay converting to 'Instant' and 'Delta'. - 'xarray' module: - Add a Rust abstraction for the 'xarray' data structure. This abstraction allows Rust code to leverage the 'xarray' to store types that implement 'ForeignOwnable'. This support is a dependency for memory backing feature of the Rust null block driver, which is waiting to be merged. - Set up an entry in 'MAINTAINERS' for the XArray Rust support. Patches will go to the new Rust XArray tree and then via the Rust subsystem tree for now. - Allow 'ForeignOwnable' to carry information about the pointed-to type. This helps asserting alignment requirements for the pointer passed to the foreign language. - 'container_of!': retain pointer mut-ness and add a compile-time check of the type of the first parameter ('$field_ptr'). - Support optional message in 'static_assert!'. - Add C FFI types (e.g. 'c_int') to the prelude. - 'str' module: simplify KUnit tests 'format!' macro, convert 'rusttest' tests into KUnit, take advantage of the '-> Result' support in KUnit '#[test]'s. - 'list' module: add examples for 'List', fix path of 'assert_pinned!' (so far unused macro rule). - 'workqueue' module: remove 'HasWork::OFFSET'. - 'page' module: add 'inline' attribute. 'macros' crate: - 'module' macro: place 'cleanup_module()' in '.exit.text' section. 'pin-init' crate: - Add 'Wrapper<T>' trait for creating pin-initializers for wrapper structs with a structurally pinned value such as 'UnsafeCell<T>' or 'MaybeUninit<T>'. - Add 'MaybeZeroable' derive macro to try to derive 'Zeroable', but not error if not all fields implement it. This is needed to derive 'Zeroable' for all bindgen-generated structs. - Add 'unsafe fn cast_[pin_]init()' functions to unsafely change the initialized type of an initializer. These are utilized by the 'Wrapper<T>' implementations. - Add support for visibility in 'Zeroable' derive macro. - Add support for 'union's in 'Zeroable' derive macro. - Upstream dev news: streamline CI, fix some bugs. Add new workflows to check if the user-space version and the one in the kernel tree have diverged. Use the issues tab [1] to track them, which should help folks report and diagnose issues w.r.t. 'pin-init' better. [1] https://github.com/rust-for-linux/pin-init/issues Documentation: - Testing: add docs on the new KUnit '#[test]' tests. - Coding guidelines: explain that '///' vs. '//' applies to private items too. Add section on C FFI types. - Quick Start guide: update Ubuntu instructions and split them into "25.04" and "24.04 LTS and older". And a few other cleanups and improvements" * tag 'rust-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (78 commits) rust: list: Fix typo `much` in arc.rs rust: check type of `$ptr` in `container_of!` rust: workqueue: remove HasWork::OFFSET rust: retain pointer mut-ness in `container_of!` Documentation: rust: testing: add docs on the new KUnit `#[test]` tests Documentation: rust: rename `#[test]`s to "`rusttest` host tests" rust: str: take advantage of the `-> Result` support in KUnit `#[test]`'s rust: str: simplify KUnit tests `format!` macro rust: str: convert `rusttest` tests into KUnit rust: add `kunit_tests` to the prelude rust: kunit: support checked `-> Result`s in KUnit `#[test]`s rust: kunit: support KUnit-mapped `assert!` macros in `#[test]`s rust: make section names plural rust: list: fix path of `assert_pinned!` rust: compile libcore with edition 2024 for 1.87+ rust: dma: add missing Markdown code span rust: task: add missing Markdown code spans and intra-doc links rust: pci: fix docs related to missing Markdown code spans rust: alloc: add missing Markdown code span rust: alloc: add missing Markdown code spans ...
2025-05-20rust: cpufreq: Extend abstractions for driver registrationViresh Kumar
Extend the cpufreq abstractions to support driver registration from Rust. Reviewed-by: Danilo Krummrich <dakr@kernel.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2025-05-20rust: cpufreq: Extend abstractions for policy and driver opsViresh Kumar
Extend the cpufreq abstractions to include support for policy handling and driver operations. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2025-05-20rust: cpufreq: Add initial abstractions for cpufreq frameworkViresh Kumar
Introduce initial Rust abstractions for the cpufreq core. This includes basic representations for cpufreq flags, relation types, and the cpufreq table. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>