* [PATCH v5 00/20] Rust support
@ 2022-03-17 18:09 Miguel Ojeda
2022-03-17 18:10 ` [PATCH v5 19/20] [RFC] drivers: gpio: PrimeCell PL061 in Rust Miguel Ojeda
0 siblings, 1 reply; 2+ messages in thread
From: Miguel Ojeda @ 2022-03-17 18:09 UTC (permalink / raw)
To: Linus Torvalds, Greg Kroah-Hartman
Cc: rust-for-linux, linux-kernel, Miguel Ojeda, linux-arm-kernel,
linux-doc, linux-gpio, linux-kbuild, linux-perf-users,
linuxppc-dev, linux-riscv, live-patching
Rust support
This is the patch series (v5) to add support for Rust as a second
language to the Linux kernel.
If you are interested in following this effort, please join us in
the mailing list at:
rust-for-linux@vger.kernel.org
and take a look at the project itself at:
https://github.com/Rust-for-Linux
As usual, special thanks go to ISRG (Internet Security Research
Group) and Google for their financial support on this endeavor.
Cheers,
Miguel
--
# Rust support
This cover letter explains the major changes and updates done since
the previous ones. For those, please see:
RFC: https://lore.kernel.org/lkml/20210414184604.23473-1-ojeda@kernel.org/
v1: https://lore.kernel.org/lkml/20210704202756.29107-1-ojeda@kernel.org/
v2: https://lore.kernel.org/lkml/20211206140313.5653-1-ojeda@kernel.org/
v3: https://lore.kernel.org/lkml/20220117053349.6804-1-ojeda@kernel.org/
v4: https://lore.kernel.org/lkml/20220212130410.6901-1-ojeda@kernel.org/
## Infrastructure updates
There have been several improvements to the overall Rust support:
- The toolchain and `alloc` have been upgraded to Rust 1.59.0.
This version stabilized `feature(global_asm)` as well as
the `-Csymbol-mangling-version=v0` flag.
- Added support for host programs written in Rust. This should
only be used in scenarios where Rust is required to be available.
- Target specification files are now generated on the fly based
on the kernel configuration, via a Rust script, instead of
having a few predefined files.
The content of the generated file has been simplified and,
for x86, all the options that can be specified through the
command-line have been moved to the architecture `Makefile`.
The goal is to reduce the content of the file as much as possible
for all architectures, and eventually, stop needing such a file.
- Added `HAVE_RUST` kernel option. This symbol should be selected
by an architecture if it supports Rust.
- Added documentation on `RUSTFLAGS*` and `KBUILD_RUST*` variables.
- Simplified tags and cross-references in the documentation.
- Other cleanups, fixes and improvements on the build system.
## Abstractions and driver updates
Some of the improvements to the abstractions and example drivers are:
- Added abstraction for the Hardware Random Number Generator.
- `%pA` rework in `vsprintf` following the review.
- The `sync` sample now shows how to use static mutexes and
conditional variables.
- Error codes can now be used without prefixing them with
`Error::`, which makes using them closer to C. For instance:
fn f(...) -> Result {
if ... {
return Err(EINVAL);
}
...
Ok(())
}
- Added `CString` type for owned C strings.
- `miscdev` registration now holds an owned C string, which enables
scenarios when the device name is constructed at runtime.
- Added `Bool` trait meant to be used in type states to allow
boolean constraints in implementation blocks.
- Added `LockInfo` trait that lock "type states" must implement.
This allows the definition of additional writable type states.
- Simplification of the spin lock implementation by splitting
acquisition types. Type states are used to implement two versions
of the `Lock` trait: one which never modifies the interrupt state
and one that disables them (if they are enabled, then re-enables
on unlock).
- `Result::unwrap` can now be used in examples that are compiled,
linked and run.
- Merged `Formatter` and `Buffer` types.
- Added `IoMem::offset_ok` for runtime sizes.
- Other cleanups, fixes and improvements.
## Patch series status
The Rust support is still to be considered experimental. However,
support is good enough that kernel developers can start working on the
Rust abstractions for subsystems and write drivers and other modules.
The current series has just arrived in `linux-next`, as usual.
Similarly, the preview docs for this series can be seen at:
https://rust-for-linux.github.io/docs/kernel/
As usual, please see the following link for the
live list of unstable Rust features we are using:
https://github.com/Rust-for-Linux/linux/issues/2
Note that this time the series depends on a patch queued in
powerpc-next:
https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?h=next&id=d4be60fe66b7380530868ceebe549f8eebccacc5
## Acknowledgements
The signatures in the main commits correspond to the people that
wrote code that has ended up in them at the present time. For details
on contributions to code and discussions, please see our repository:
https://github.com/Rust-for-Linux/linux
However, we would like to give credit to everyone that has contributed
in one way or another to the Rust for Linux project. Since the
previous cover letter:
- Akira Yokosawa for a detailed review of the documentation and
suggesting several improvements.
- Petr Mladek and Rasmus Villemoes for their printing/formatting
review and suggestions.
- Russell King for his review of the Kconfig changes.
- Andy Shevchenko, Sergey Senozhatsky, John Paul Adrian Glaubitz
and David Laight for their reviews and feedback on the previous
round.
- bjorn3 for reviewing many PRs.
- As usual, bjorn3 and Gary Guo for all the input on Rust compiler
details and suggestions.
- Philip Li, Yujie Liu et al. for continuing their work on adding
Rust support to the Intel 0DAY/LKP kernel test robot. Also,
thanks to Nathan Chancellor and Nick Desaulniers for their input.
- Wei Liu for taking the time to answer questions from newcomers
in Zulip.
- Antoni Boucher (and his supporters) et al. for their ongoing
work on `rustc_codegen_gcc`.
- Philip Herrons (and his supporters Open Source Security and
Embecosm) et al. for their ongoing work on GCC Rust.
- Mats Larsen, Marc Poulhiès et al. for their ongoing work on
improving Rust support in Compiler Explorer.
- Many folks that have reported issues, tested the project,
helped spread the word, joined discussions and contributed in
other ways!
Please see also the acknowledgements on the previous cover letters.
Boqun Feng (1):
kallsyms: use the correct buffer size for symbols
Gary Guo (2):
rust: add `build_error` crate
vsprintf: add new `%pA` format specifier
Miguel Ojeda (13):
kallsyms: support "big" kernel symbols
kallsyms: increase maximum kernel symbol length to 512
rust: add C helpers
rust: add `compiler_builtins` crate
rust: add `alloc` crate
rust: add `macros` crate
rust: export generated symbols
scripts: add `generate_rust_analyzer.py`
scripts: decode_stacktrace: demangle Rust symbols
docs: add Rust documentation
Kbuild: add Rust support
samples: add Rust examples
MAINTAINERS: Rust
Wedson Almeida Filho (4):
rust: add `kernel` crate's `sync` module
rust: add `kernel` crate
[RFC] drivers: gpio: PrimeCell PL061 in Rust
[RFC] drivers: android: Binder IPC in Rust
.gitignore | 5 +
.rustfmt.toml | 12 +
Documentation/doc-guide/kernel-doc.rst | 3 +
Documentation/index.rst | 1 +
Documentation/kbuild/kbuild.rst | 17 +
Documentation/kbuild/makefiles.rst | 50 +-
Documentation/process/changes.rst | 41 +
Documentation/rust/arch-support.rst | 34 +
Documentation/rust/coding-guidelines.rst | 214 ++
Documentation/rust/general-information.rst | 77 +
Documentation/rust/index.rst | 20 +
Documentation/rust/logo.svg | 357 ++
Documentation/rust/quick-start.rst | 230 ++
MAINTAINERS | 15 +
Makefile | 173 +-
arch/Kconfig | 6 +
arch/arm/Kconfig | 1 +
arch/arm64/Kconfig | 1 +
arch/powerpc/Kconfig | 1 +
arch/riscv/Kconfig | 1 +
arch/riscv/Makefile | 5 +
arch/x86/Kconfig | 1 +
arch/x86/Makefile | 14 +
drivers/android/Kconfig | 6 +
drivers/android/Makefile | 2 +
drivers/android/allocation.rs | 266 ++
drivers/android/context.rs | 80 +
drivers/android/defs.rs | 99 +
drivers/android/node.rs | 476 +++
drivers/android/process.rs | 960 +++++
drivers/android/range_alloc.rs | 189 +
drivers/android/rust_binder.rs | 111 +
drivers/android/thread.rs | 870 +++++
drivers/android/transaction.rs | 326 ++
drivers/gpio/Kconfig | 8 +
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio_pl061_rust.rs | 370 ++
include/linux/kallsyms.h | 2 +-
include/linux/spinlock.h | 17 +-
include/uapi/linux/android/binder.h | 28 +-
init/Kconfig | 44 +-
kernel/kallsyms.c | 26 +-
kernel/livepatch/core.c | 4 +-
lib/Kconfig.debug | 143 +
lib/vsprintf.c | 13 +
rust/.gitignore | 8 +
rust/Makefile | 376 ++
rust/alloc/README.md | 32 +
rust/alloc/alloc.rs | 440 +++
rust/alloc/borrow.rs | 498 +++
rust/alloc/boxed.rs | 2008 +++++++++++
rust/alloc/collections/mod.rs | 156 +
rust/alloc/fmt.rs | 601 ++++
rust/alloc/lib.rs | 231 ++
rust/alloc/macros.rs | 126 +
rust/alloc/raw_vec.rs | 561 +++
rust/alloc/slice.rs | 1279 +++++++
rust/alloc/str.rs | 632 ++++
rust/alloc/string.rs | 2862 +++++++++++++++
rust/alloc/vec/drain.rs | 186 +
rust/alloc/vec/drain_filter.rs | 145 +
rust/alloc/vec/into_iter.rs | 356 ++
rust/alloc/vec/is_zero.rs | 106 +
rust/alloc/vec/mod.rs | 3353 ++++++++++++++++++
rust/alloc/vec/partial_eq.rs | 49 +
rust/alloc/vec/set_len_on_drop.rs | 30 +
rust/alloc/vec/spec_extend.rs | 174 +
rust/bindgen_parameters | 13 +
rust/build_error.rs | 29 +
rust/compiler_builtins.rs | 57 +
rust/exports.c | 20 +
rust/helpers.c | 531 +++
rust/kernel/allocator.rs | 65 +
rust/kernel/amba.rs | 259 ++
rust/kernel/bindings.rs | 47 +
rust/kernel/bindings_helper.h | 37 +
rust/kernel/build_assert.rs | 80 +
rust/kernel/c_types.rs | 119 +
rust/kernel/chrdev.rs | 207 ++
rust/kernel/clk.rs | 75 +
rust/kernel/cred.rs | 73 +
rust/kernel/device.rs | 554 +++
rust/kernel/driver.rs | 440 +++
rust/kernel/error.rs | 560 +++
rust/kernel/file.rs | 873 +++++
rust/kernel/gpio.rs | 478 +++
rust/kernel/hwrng.rs | 242 ++
rust/kernel/io_buffer.rs | 153 +
rust/kernel/io_mem.rs | 237 ++
rust/kernel/iov_iter.rs | 81 +
rust/kernel/irq.rs | 409 +++
rust/kernel/lib.rs | 260 ++
rust/kernel/linked_list.rs | 247 ++
rust/kernel/miscdev.rs | 291 ++
rust/kernel/mm.rs | 149 +
rust/kernel/module_param.rs | 498 +++
rust/kernel/of.rs | 63 +
rust/kernel/pages.rs | 144 +
rust/kernel/platform.rs | 224 ++
rust/kernel/power.rs | 118 +
rust/kernel/prelude.rs | 36 +
rust/kernel/print.rs | 414 +++
rust/kernel/random.rs | 50 +
rust/kernel/raw_list.rs | 361 ++
rust/kernel/rbtree.rs | 562 +++
rust/kernel/revocable.rs | 163 +
rust/kernel/security.rs | 36 +
rust/kernel/static_assert.rs | 39 +
rust/kernel/std_vendor.rs | 150 +
rust/kernel/str.rs | 592 ++++
rust/kernel/sync/arc.rs | 500 +++
rust/kernel/sync/condvar.rs | 138 +
rust/kernel/sync/guard.rs | 166 +
rust/kernel/sync/locked_by.rs | 112 +
rust/kernel/sync/mod.rs | 157 +
rust/kernel/sync/mutex.rs | 114 +
rust/kernel/sync/revocable_mutex.rs | 184 +
rust/kernel/sync/rwsem.rs | 149 +
rust/kernel/sync/seqlock.rs | 202 ++
rust/kernel/sync/spinlock.rs | 192 +
rust/kernel/sysctl.rs | 199 ++
rust/kernel/task.rs | 182 +
rust/kernel/types.rs | 569 +++
rust/kernel/user_ptr.rs | 175 +
rust/macros/helpers.rs | 79 +
rust/macros/lib.rs | 94 +
rust/macros/module.rs | 631 ++++
samples/Kconfig | 2 +
samples/Makefile | 1 +
samples/rust/Kconfig | 130 +
samples/rust/Makefile | 15 +
samples/rust/hostprogs/.gitignore | 3 +
samples/rust/hostprogs/Makefile | 5 +
samples/rust/hostprogs/a.rs | 7 +
samples/rust/hostprogs/b.rs | 5 +
samples/rust/hostprogs/single.rs | 12 +
samples/rust/rust_chrdev.rs | 50 +
samples/rust/rust_minimal.rs | 35 +
samples/rust/rust_miscdev.rs | 143 +
samples/rust/rust_module_parameters.rs | 69 +
samples/rust/rust_platform.rs | 22 +
samples/rust/rust_print.rs | 54 +
samples/rust/rust_random.rs | 60 +
samples/rust/rust_semaphore.rs | 171 +
samples/rust/rust_semaphore_c.c | 212 ++
samples/rust/rust_stack_probing.rs | 36 +
samples/rust/rust_sync.rs | 93 +
scripts/.gitignore | 1 +
scripts/Kconfig.include | 6 +-
scripts/Makefile | 3 +
scripts/Makefile.build | 60 +
scripts/Makefile.debug | 10 +
scripts/Makefile.host | 34 +-
scripts/Makefile.lib | 12 +
scripts/Makefile.modfinal | 8 +-
scripts/cc-version.sh | 12 +-
scripts/decode_stacktrace.sh | 14 +
scripts/generate_rust_analyzer.py | 133 +
scripts/generate_rust_target.rs | 227 ++
scripts/is_rust_module.sh | 13 +
scripts/kallsyms.c | 40 +-
scripts/kconfig/confdata.c | 75 +
scripts/min-tool-version.sh | 6 +
scripts/rust-is-available-bindgen-libclang.h | 2 +
scripts/rust-is-available.sh | 158 +
tools/include/linux/kallsyms.h | 2 +-
tools/lib/perf/include/perf/event.h | 2 +-
tools/lib/symbol/kallsyms.h | 2 +-
168 files changed, 35290 insertions(+), 63 deletions(-)
create mode 100644 .rustfmt.toml
create mode 100644 Documentation/rust/arch-support.rst
create mode 100644 Documentation/rust/coding-guidelines.rst
create mode 100644 Documentation/rust/general-information.rst
create mode 100644 Documentation/rust/index.rst
create mode 100644 Documentation/rust/logo.svg
create mode 100644 Documentation/rust/quick-start.rst
create mode 100644 drivers/android/allocation.rs
create mode 100644 drivers/android/context.rs
create mode 100644 drivers/android/defs.rs
create mode 100644 drivers/android/node.rs
create mode 100644 drivers/android/process.rs
create mode 100644 drivers/android/range_alloc.rs
create mode 100644 drivers/android/rust_binder.rs
create mode 100644 drivers/android/thread.rs
create mode 100644 drivers/android/transaction.rs
create mode 100644 drivers/gpio/gpio_pl061_rust.rs
create mode 100644 rust/.gitignore
create mode 100644 rust/Makefile
create mode 100644 rust/alloc/README.md
create mode 100644 rust/alloc/alloc.rs
create mode 100644 rust/alloc/borrow.rs
create mode 100644 rust/alloc/boxed.rs
create mode 100644 rust/alloc/collections/mod.rs
create mode 100644 rust/alloc/fmt.rs
create mode 100644 rust/alloc/lib.rs
create mode 100644 rust/alloc/macros.rs
create mode 100644 rust/alloc/raw_vec.rs
create mode 100644 rust/alloc/slice.rs
create mode 100644 rust/alloc/str.rs
create mode 100644 rust/alloc/string.rs
create mode 100644 rust/alloc/vec/drain.rs
create mode 100644 rust/alloc/vec/drain_filter.rs
create mode 100644 rust/alloc/vec/into_iter.rs
create mode 100644 rust/alloc/vec/is_zero.rs
create mode 100644 rust/alloc/vec/mod.rs
create mode 100644 rust/alloc/vec/partial_eq.rs
create mode 100644 rust/alloc/vec/set_len_on_drop.rs
create mode 100644 rust/alloc/vec/spec_extend.rs
create mode 100644 rust/bindgen_parameters
create mode 100644 rust/build_error.rs
create mode 100644 rust/compiler_builtins.rs
create mode 100644 rust/exports.c
create mode 100644 rust/helpers.c
create mode 100644 rust/kernel/allocator.rs
create mode 100644 rust/kernel/amba.rs
create mode 100644 rust/kernel/bindings.rs
create mode 100644 rust/kernel/bindings_helper.h
create mode 100644 rust/kernel/build_assert.rs
create mode 100644 rust/kernel/c_types.rs
create mode 100644 rust/kernel/chrdev.rs
create mode 100644 rust/kernel/clk.rs
create mode 100644 rust/kernel/cred.rs
create mode 100644 rust/kernel/device.rs
create mode 100644 rust/kernel/driver.rs
create mode 100644 rust/kernel/error.rs
create mode 100644 rust/kernel/file.rs
create mode 100644 rust/kernel/gpio.rs
create mode 100644 rust/kernel/hwrng.rs
create mode 100644 rust/kernel/io_buffer.rs
create mode 100644 rust/kernel/io_mem.rs
create mode 100644 rust/kernel/iov_iter.rs
create mode 100644 rust/kernel/irq.rs
create mode 100644 rust/kernel/lib.rs
create mode 100644 rust/kernel/linked_list.rs
create mode 100644 rust/kernel/miscdev.rs
create mode 100644 rust/kernel/mm.rs
create mode 100644 rust/kernel/module_param.rs
create mode 100644 rust/kernel/of.rs
create mode 100644 rust/kernel/pages.rs
create mode 100644 rust/kernel/platform.rs
create mode 100644 rust/kernel/power.rs
create mode 100644 rust/kernel/prelude.rs
create mode 100644 rust/kernel/print.rs
create mode 100644 rust/kernel/random.rs
create mode 100644 rust/kernel/raw_list.rs
create mode 100644 rust/kernel/rbtree.rs
create mode 100644 rust/kernel/revocable.rs
create mode 100644 rust/kernel/security.rs
create mode 100644 rust/kernel/static_assert.rs
create mode 100644 rust/kernel/std_vendor.rs
create mode 100644 rust/kernel/str.rs
create mode 100644 rust/kernel/sync/arc.rs
create mode 100644 rust/kernel/sync/condvar.rs
create mode 100644 rust/kernel/sync/guard.rs
create mode 100644 rust/kernel/sync/locked_by.rs
create mode 100644 rust/kernel/sync/mod.rs
create mode 100644 rust/kernel/sync/mutex.rs
create mode 100644 rust/kernel/sync/revocable_mutex.rs
create mode 100644 rust/kernel/sync/rwsem.rs
create mode 100644 rust/kernel/sync/seqlock.rs
create mode 100644 rust/kernel/sync/spinlock.rs
create mode 100644 rust/kernel/sysctl.rs
create mode 100644 rust/kernel/task.rs
create mode 100644 rust/kernel/types.rs
create mode 100644 rust/kernel/user_ptr.rs
create mode 100644 rust/macros/helpers.rs
create mode 100644 rust/macros/lib.rs
create mode 100644 rust/macros/module.rs
create mode 100644 samples/rust/Kconfig
create mode 100644 samples/rust/Makefile
create mode 100644 samples/rust/hostprogs/.gitignore
create mode 100644 samples/rust/hostprogs/Makefile
create mode 100644 samples/rust/hostprogs/a.rs
create mode 100644 samples/rust/hostprogs/b.rs
create mode 100644 samples/rust/hostprogs/single.rs
create mode 100644 samples/rust/rust_chrdev.rs
create mode 100644 samples/rust/rust_minimal.rs
create mode 100644 samples/rust/rust_miscdev.rs
create mode 100644 samples/rust/rust_module_parameters.rs
create mode 100644 samples/rust/rust_platform.rs
create mode 100644 samples/rust/rust_print.rs
create mode 100644 samples/rust/rust_random.rs
create mode 100644 samples/rust/rust_semaphore.rs
create mode 100644 samples/rust/rust_semaphore_c.c
create mode 100644 samples/rust/rust_stack_probing.rs
create mode 100644 samples/rust/rust_sync.rs
create mode 100755 scripts/generate_rust_analyzer.py
create mode 100644 scripts/generate_rust_target.rs
create mode 100755 scripts/is_rust_module.sh
create mode 100644 scripts/rust-is-available-bindgen-libclang.h
create mode 100755 scripts/rust-is-available.sh
base-commit: 09688c0166e76ce2fb85e86b9d99be8b0084cdf9
--
2.35.1
^ permalink raw reply [flat|nested] 2+ messages in thread* [PATCH v5 19/20] [RFC] drivers: gpio: PrimeCell PL061 in Rust 2022-03-17 18:09 [PATCH v5 00/20] Rust support Miguel Ojeda @ 2022-03-17 18:10 ` Miguel Ojeda 0 siblings, 0 replies; 2+ messages in thread From: Miguel Ojeda @ 2022-03-17 18:10 UTC (permalink / raw) To: Linus Torvalds, Greg Kroah-Hartman Cc: rust-for-linux, linux-kernel, Miguel Ojeda, Wedson Almeida Filho, Linus Walleij, Bartosz Golaszewski, linux-gpio From: Wedson Almeida Filho <wedsonaf@google.com> A port to Rust of the PrimeCell PL061 GPIO driver. This module is a work in progress and will be sent for review later on, as well as separately from the Rust support. However, it is included to show how an actual working module written in Rust may look like. Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com> Signed-off-by: Miguel Ojeda <ojeda@kernel.org> --- drivers/gpio/Kconfig | 8 + drivers/gpio/Makefile | 1 + drivers/gpio/gpio_pl061_rust.rs | 370 ++++++++++++++++++++++++++++++++ 3 files changed, 379 insertions(+) create mode 100644 drivers/gpio/gpio_pl061_rust.rs diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index 1c211b4c63be..172295770c3d 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -471,6 +471,14 @@ config GPIO_PL061 help Say yes here to support the PrimeCell PL061 GPIO device. +config GPIO_PL061_RUST + tristate "PrimeCell PL061 GPIO support written in Rust" + depends on ARM_AMBA && RUST + select IRQ_DOMAIN + select GPIOLIB_IRQCHIP + help + Say yes here to support the PrimeCell PL061 GPIO device + config GPIO_PMIC_EIC_SPRD tristate "Spreadtrum PMIC EIC support" depends on MFD_SC27XX_PMIC || COMPILE_TEST diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index edbaa3cb343c..7dc334df9c3f 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -117,6 +117,7 @@ obj-$(CONFIG_GPIO_PCIE_IDIO_24) += gpio-pcie-idio-24.o obj-$(CONFIG_GPIO_PCI_IDIO_16) += gpio-pci-idio-16.o obj-$(CONFIG_GPIO_PISOSR) += gpio-pisosr.o obj-$(CONFIG_GPIO_PL061) += gpio-pl061.o +obj-$(CONFIG_GPIO_PL061_RUST) += gpio_pl061_rust.o obj-$(CONFIG_GPIO_PMIC_EIC_SPRD) += gpio-pmic-eic-sprd.o obj-$(CONFIG_GPIO_PXA) += gpio-pxa.o obj-$(CONFIG_GPIO_RASPBERRYPI_EXP) += gpio-raspberrypi-exp.o diff --git a/drivers/gpio/gpio_pl061_rust.rs b/drivers/gpio/gpio_pl061_rust.rs new file mode 100644 index 000000000000..e0a12d3b65c7 --- /dev/null +++ b/drivers/gpio/gpio_pl061_rust.rs @@ -0,0 +1,370 @@ +// SPDX-License-Identifier: GPL-2.0 + +//! Driver for the ARM PrimeCell(tm) General Purpose Input/Output (PL061). +//! +//! Based on the C driver written by Baruch Siach <baruch@tkos.co.il>. + +use kernel::{ + amba, bit, bits_iter, define_amba_id_table, device, gpio, + io_mem::IoMem, + irq::{self, ExtraResult, IrqData, LockedIrqData}, + power, + prelude::*, + sync::{Ref, RefBorrow, SpinLock}, +}; + +const GPIODIR: usize = 0x400; +const GPIOIS: usize = 0x404; +const GPIOIBE: usize = 0x408; +const GPIOIEV: usize = 0x40C; +const GPIOIE: usize = 0x410; +const GPIOMIS: usize = 0x418; +const GPIOIC: usize = 0x41C; +const GPIO_SIZE: usize = 0x1000; + +const PL061_GPIO_NR: u16 = 8; + +#[derive(Default)] +struct ContextSaveRegs { + gpio_data: u8, + gpio_dir: u8, + gpio_is: u8, + gpio_ibe: u8, + gpio_iev: u8, + gpio_ie: u8, +} + +#[derive(Default)] +struct PL061DataInner { + csave_regs: ContextSaveRegs, +} + +struct PL061Data { + dev: device::Device, + inner: SpinLock<PL061DataInner>, +} + +struct PL061Resources { + base: IoMem<GPIO_SIZE>, + parent_irq: u32, +} + +type PL061Registrations = gpio::RegistrationWithIrqChip<PL061Device>; + +type DeviceData = device::Data<PL061Registrations, PL061Resources, PL061Data>; + +struct PL061Device; + +impl gpio::Chip for PL061Device { + type Data = Ref<DeviceData>; + + kernel::declare_gpio_chip_operations!( + get_direction, + direction_input, + direction_output, + get, + set + ); + + fn get_direction(data: RefBorrow<'_, DeviceData>, offset: u32) -> Result<gpio::LineDirection> { + let pl061 = data.resources().ok_or(ENXIO)?; + Ok(if pl061.base.readb(GPIODIR) & bit(offset) != 0 { + gpio::LineDirection::Out + } else { + gpio::LineDirection::In + }) + } + + fn direction_input(data: RefBorrow<'_, DeviceData>, offset: u32) -> Result { + let _guard = data.inner.lock_irqdisable(); + let pl061 = data.resources().ok_or(ENXIO)?; + let mut gpiodir = pl061.base.readb(GPIODIR); + gpiodir &= !bit(offset); + pl061.base.writeb(gpiodir, GPIODIR); + Ok(()) + } + + fn direction_output(data: RefBorrow<'_, DeviceData>, offset: u32, value: bool) -> Result { + let woffset = bit(offset + 2).into(); + let _guard = data.inner.lock_irqdisable(); + let pl061 = data.resources().ok_or(ENXIO)?; + pl061.base.try_writeb((value as u8) << offset, woffset)?; + let mut gpiodir = pl061.base.readb(GPIODIR); + gpiodir |= bit(offset); + pl061.base.writeb(gpiodir, GPIODIR); + + // gpio value is set again, because pl061 doesn't allow to set value of a gpio pin before + // configuring it in OUT mode. + pl061.base.try_writeb((value as u8) << offset, woffset)?; + Ok(()) + } + + fn get(data: RefBorrow<'_, DeviceData>, offset: u32) -> Result<bool> { + let pl061 = data.resources().ok_or(ENXIO)?; + Ok(pl061.base.try_readb(bit(offset + 2).into())? != 0) + } + + fn set(data: RefBorrow<'_, DeviceData>, offset: u32, value: bool) { + if let Some(pl061) = data.resources() { + let woffset = bit(offset + 2).into(); + let _ = pl061.base.try_writeb((value as u8) << offset, woffset); + } + } +} + +impl gpio::ChipWithIrqChip for PL061Device { + fn handle_irq_flow( + data: RefBorrow<'_, DeviceData>, + desc: &irq::Descriptor, + domain: &irq::Domain, + ) { + let chained = desc.enter_chained(); + + if let Some(pl061) = data.resources() { + let pending = pl061.base.readb(GPIOMIS); + for offset in bits_iter(pending) { + domain.generic_handle_chained(offset, &chained); + } + } + } +} + +impl irq::Chip for PL061Device { + type Data = Ref<DeviceData>; + + kernel::declare_irq_chip_operations!(set_type, set_wake); + + fn set_type( + data: RefBorrow<'_, DeviceData>, + irq_data: &mut LockedIrqData, + trigger: u32, + ) -> Result<ExtraResult> { + let offset = irq_data.hwirq(); + let bit = bit(offset); + + if offset >= PL061_GPIO_NR.into() { + return Err(EINVAL); + } + + if trigger & (irq::Type::LEVEL_HIGH | irq::Type::LEVEL_LOW) != 0 + && trigger & (irq::Type::EDGE_RISING | irq::Type::EDGE_FALLING) != 0 + { + dev_err!( + data.dev, + "trying to configure line {} for both level and edge detection, choose one!\n", + offset + ); + return Err(EINVAL); + } + + let _guard = data.inner.lock_irqdisable(); + let pl061 = data.resources().ok_or(ENXIO)?; + + let mut gpioiev = pl061.base.readb(GPIOIEV); + let mut gpiois = pl061.base.readb(GPIOIS); + let mut gpioibe = pl061.base.readb(GPIOIBE); + + if trigger & (irq::Type::LEVEL_HIGH | irq::Type::LEVEL_LOW) != 0 { + let polarity = trigger & irq::Type::LEVEL_HIGH != 0; + + // Disable edge detection. + gpioibe &= !bit; + // Enable level detection. + gpiois |= bit; + // Select polarity. + if polarity { + gpioiev |= bit; + } else { + gpioiev &= !bit; + } + irq_data.set_level_handler(); + dev_dbg!( + data.dev, + "line {}: IRQ on {} level\n", + offset, + if polarity { "HIGH" } else { "LOW" } + ); + } else if (trigger & irq::Type::EDGE_BOTH) == irq::Type::EDGE_BOTH { + // Disable level detection. + gpiois &= !bit; + // Select both edges, settings this makes GPIOEV be ignored. + gpioibe |= bit; + irq_data.set_edge_handler(); + dev_dbg!(data.dev, "line {}: IRQ on both edges\n", offset); + } else if trigger & (irq::Type::EDGE_RISING | irq::Type::EDGE_FALLING) != 0 { + let rising = trigger & irq::Type::EDGE_RISING != 0; + + // Disable level detection. + gpiois &= !bit; + // Clear detection on both edges. + gpioibe &= !bit; + // Select edge. + if rising { + gpioiev |= bit; + } else { + gpioiev &= !bit; + } + irq_data.set_edge_handler(); + dev_dbg!( + data.dev, + "line {}: IRQ on {} edge\n", + offset, + if rising { "RISING" } else { "FALLING}" } + ); + } else { + // No trigger: disable everything. + gpiois &= !bit; + gpioibe &= !bit; + gpioiev &= !bit; + irq_data.set_bad_handler(); + dev_warn!(data.dev, "no trigger selected for line {}\n", offset); + } + + pl061.base.writeb(gpiois, GPIOIS); + pl061.base.writeb(gpioibe, GPIOIBE); + pl061.base.writeb(gpioiev, GPIOIEV); + + Ok(ExtraResult::None) + } + + fn mask(data: RefBorrow<'_, DeviceData>, irq_data: &IrqData) { + let mask = bit(irq_data.hwirq() % irq::HwNumber::from(PL061_GPIO_NR)); + let _guard = data.inner.lock(); + if let Some(pl061) = data.resources() { + let gpioie = pl061.base.readb(GPIOIE) & !mask; + pl061.base.writeb(gpioie, GPIOIE); + } + } + + fn unmask(data: RefBorrow<'_, DeviceData>, irq_data: &IrqData) { + let mask = bit(irq_data.hwirq() % irq::HwNumber::from(PL061_GPIO_NR)); + let _guard = data.inner.lock(); + if let Some(pl061) = data.resources() { + let gpioie = pl061.base.readb(GPIOIE) | mask; + pl061.base.writeb(gpioie, GPIOIE); + } + } + + // This gets called from the edge IRQ handler to ACK the edge IRQ in the GPIOIC + // (interrupt-clear) register. For level IRQs this is not needed: these go away when the level + // signal goes away. + fn ack(data: RefBorrow<'_, DeviceData>, irq_data: &IrqData) { + let mask = bit(irq_data.hwirq() % irq::HwNumber::from(PL061_GPIO_NR)); + let _guard = data.inner.lock(); + if let Some(pl061) = data.resources() { + pl061.base.writeb(mask.into(), GPIOIC); + } + } + + fn set_wake(data: RefBorrow<'_, DeviceData>, _irq_data: &IrqData, on: bool) -> Result { + let pl061 = data.resources().ok_or(ENXIO)?; + irq::set_wake(pl061.parent_irq, on) + } +} + +impl amba::Driver for PL061Device { + type Data = Ref<DeviceData>; + type PowerOps = Self; + + define_amba_id_table! {(), [ + ({id: 0x00041061, mask: 0x000fffff}, None), + ]} + + fn probe(dev: &mut amba::Device, _data: Option<&Self::IdInfo>) -> Result<Ref<DeviceData>> { + let res = dev.take_resource().ok_or(ENXIO)?; + let irq = dev.irq(0).ok_or(ENXIO)?; + + let mut data = kernel::new_device_data!( + gpio::RegistrationWithIrqChip::new(), + PL061Resources { + // SAFETY: This device doesn't support DMA. + base: unsafe { IoMem::try_new(res)? }, + parent_irq: irq, + }, + PL061Data { + dev: device::Device::from_dev(dev), + // SAFETY: We call `spinlock_init` below. + inner: unsafe { SpinLock::new(PL061DataInner::default()) }, + }, + "PL061::Registrations" + )?; + + // SAFETY: General part of the data is pinned when `data` is. + let gen_inner = unsafe { data.as_mut().map_unchecked_mut(|d| &mut (**d).inner) }; + kernel::spinlock_init!(gen_inner, "PL061Data::inner"); + + let data = Ref::<DeviceData>::from(data); + + data.resources().ok_or(ENXIO)?.base.writeb(0, GPIOIE); // disable irqs + + data.registrations() + .ok_or(ENXIO)? + .as_pinned_mut() + .register::<Self>(PL061_GPIO_NR, None, dev, data.clone(), irq)?; + + dev_info!(data.dev, "PL061 GPIO chip registered\n"); + + Ok(data) + } +} + +impl power::Operations for PL061Device { + type Data = Ref<DeviceData>; + + fn suspend(data: RefBorrow<'_, DeviceData>) -> Result { + let mut inner = data.inner.lock(); + let pl061 = data.resources().ok_or(ENXIO)?; + inner.csave_regs.gpio_data = 0; + inner.csave_regs.gpio_dir = pl061.base.readb(GPIODIR); + inner.csave_regs.gpio_is = pl061.base.readb(GPIOIS); + inner.csave_regs.gpio_ibe = pl061.base.readb(GPIOIBE); + inner.csave_regs.gpio_iev = pl061.base.readb(GPIOIEV); + inner.csave_regs.gpio_ie = pl061.base.readb(GPIOIE); + + for offset in 0..PL061_GPIO_NR { + if inner.csave_regs.gpio_dir & bit(offset) != 0 { + if let Ok(v) = <Self as gpio::Chip>::get(data, offset.into()) { + inner.csave_regs.gpio_data |= (v as u8) << offset; + } + } + } + + Ok(()) + } + + fn resume(data: RefBorrow<'_, DeviceData>) -> Result { + let inner = data.inner.lock(); + let pl061 = data.resources().ok_or(ENXIO)?; + + for offset in 0..PL061_GPIO_NR { + if inner.csave_regs.gpio_dir & bit(offset) != 0 { + let value = inner.csave_regs.gpio_data & bit(offset) != 0; + let _ = <Self as gpio::Chip>::direction_output(data, offset.into(), value); + } else { + let _ = <Self as gpio::Chip>::direction_input(data, offset.into()); + } + } + + pl061.base.writeb(inner.csave_regs.gpio_is, GPIOIS); + pl061.base.writeb(inner.csave_regs.gpio_ibe, GPIOIBE); + pl061.base.writeb(inner.csave_regs.gpio_iev, GPIOIEV); + pl061.base.writeb(inner.csave_regs.gpio_ie, GPIOIE); + + Ok(()) + } + + fn freeze(data: RefBorrow<'_, DeviceData>) -> Result { + Self::suspend(data) + } + + fn restore(data: RefBorrow<'_, DeviceData>) -> Result { + Self::resume(data) + } +} + +module_amba_driver! { + type: PL061Device, + name: b"pl061_gpio", + author: b"Wedson Almeida Filho", + license: b"GPL v2", +} -- 2.35.1 ^ permalink raw reply related [flat|nested] 2+ messages in thread
end of thread, other threads:[~2022-03-17 18:14 UTC | newest] Thread overview: 2+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2022-03-17 18:09 [PATCH v5 00/20] Rust support Miguel Ojeda 2022-03-17 18:10 ` [PATCH v5 19/20] [RFC] drivers: gpio: PrimeCell PL061 in Rust Miguel Ojeda
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