feat: ETL migration, MPMC logging, device framework overhaul, VFS/FatFS, and coding standards (#193)

* refactor(main): use make_unique for test task creation

Replace raw new TaskControlBlock with sk_std::make_unique and .release()
before passing to AddTask. Ensures exception-safe construction while
maintaining AddTask's raw pointer interface.

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* 3rd: add etl

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* 3rd: add etl

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* docs(plans): add ETL migration plan

Add comprehensive ETL migration plan (Tasks 0-10) for replacing sk_std:: containers with ETL-backed kstd:: wrappers. Remove superseded unique_ptr design/implementation docs.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(build): integrate ETL library into kernel build

Add etl::etl to kernel link libraries in compile_config.cmake.
Add etl_profile.h with ETL_CPP23_SUPPORTED and ETL_NO_CHECKS defines.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(libcxx): add kstd container wrappers for ETL

Add kstd namespace wrappers around ETL containers:
- kstd_pool.hpp: Pool<T,N> and PoolRef type aliases
- kstd_vector: vector, static_vector, ivector
- kstd_list: list, static_list, list_node_t
- kstd_unique_ptr: custom unique_ptr implementation
- kstd_priority_queue: reference-based priority queue
- kstd_unordered_map: pool-backed unordered_map with std::hash

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(libcxx): convert sk_std headers to kstd shims

Replace sk_std:: implementations with thin forwarding shims to kstd::
namespace. sk_vector, sk_list, sk_unique_ptr, sk_priority_queue, and
sk_unordered_map now delegate to ETL-backed kstd wrappers.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(task): migrate task subsystem to kstd containers

Replace sk_std:: containers with kstd:: static containers in schedulers
and task manager. Use static_vector, static_list, and static_unordered_map
with compile-time sizes. Mark scheduler copy/move as deleted since ETL
containers with internal storage are not copyable.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* chore(libcxx): remove unused sk_std implementations

Delete sk_shared_ptr, sk_set, sk_rb_tree, and sk_queue which have no
remaining consumers after the ETL migration.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* chore(tests): remove tests for deleted sk_std containers

Remove unit and system tests for sk_queue, sk_rb_tree, sk_set, and
sk_shared_ptr. Update test CMakeLists.txt and system_test registration
to reflect 22 remaining test cases.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: kstd

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix: ut

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* chore: add .worktrees to gitignore

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(aarch64): remove unused io.hpp include from interrupt files

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(aarch64/gic): migrate io::In/Out to etl::io_port in GIC Read/Write helpers

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(x86_64/apic): migrate io::In/Out to etl::io_port in IoApic::Read/Write

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(x86_64/apic): migrate io::In/Out to etl::io_port in LocalApic xAPIC branches

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device/virtio): migrate io::In to etl::io_port_ro in VirtioBlkDriver::Probe

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(include): delete io.hpp after full etl::io_port migration

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix(apic/virtio): use void* cast in etl::io_port_* constructors

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix(aarch64/gic): use void* cast in etl::io_port_* constructors

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(task): add kernel_config.hpp for centralized capacity constants

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(task): add etl::hash specialization for ResourceId

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(task): replace kstd::static_list with etl::list in FifoScheduler

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(task): replace kstd::static_list with etl::list in RoundRobinScheduler

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(task): replace kstd priority_queue+storage with etl::priority_queue in CfsScheduler

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(task): replace kstd containers with etl:: in TaskManager and CpuSchedData

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(task): update GetThreadGroup return type to etl::vector

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix(task): add .full() checks before all etl container insertions

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(task): remove dead kstd_vector includes after etl migration

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix(task): provide explicit etl::vector container type for sleeping_tasks priority_queue

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update include styler

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix: update cmake

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix: add math.h, waiting for c++26

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* docs: etl plans

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: replace sk_assert with assert

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: kstd

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix: update unique_ptr

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: migrate Singleton<T> to etl::singleton<T> named aliases

Replace custom Singleton<T> with etl::singleton<T> using per-type
named aliases (e.g. BasicInfoSingleton, TaskManagerSingleton) defined
centrally in kernel.h. Delete singleton.hpp. Update all call sites
from Singleton<T>::GetInstance() to TypeSingleton::instance() and
assignment-construction to TypeSingleton::create(). Update all
documentation references.

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(arch): move arch-specific singletons out of kernel.h and make interrupt controllers Interrupt members

Move arch-specific singleton type aliases from shared kernel.h into
per-arch directories, and convert interrupt controller singletons
(PlicSingleton, ApicSingleton) into private members of each arch's
Interrupt class, following the existing aarch64 pattern where Gic is
already an Interrupt member.

- Move Pl011Singleton to src/arch/aarch64/include/pl011_singleton.h
- Move SerialSingleton to file-local scope in x86_64/early_console.cpp
- Move Ns16550aSingleton to file-local scope in riscv64/interrupt_main.cpp
- Add Plic plic_ member to riscv64 Interrupt with InitPlic() deferred init
- Add Apic apic_ member to x86_64 Interrupt with InitApic() deferred init
- Move APIC creation from ArchInit() to InterruptInit() (boot order fix)
- Remove arch-specific #includes and #ifdefs from kernel.h

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(arch): remove static from Interrupt handler arrays

Since Interrupt is used as etl::singleton (only one instance), static
class members are semantically equivalent to non-static members. Remove
static to eliminate the need for out-of-class definitions in .cpp files.

- aarch64: interrupt_handlers -> interrupt_handlers_ (non-static member)
- riscv64: interrupt_handlers_, exception_handlers_ (drop static + defs)
- x86_64: interrupt_handlers_, idts_ (drop static + defs, keep alignas)

The alignas(4096) on x86_64 members propagates correctly through
etl::singleton via uninitialized_buffer_of<T> which uses
alignas(etl::alignment_of<T>::value) on its storage.

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* 3rd: add cpu_io

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(arch): move arch-specific singletons from kernel.h to arch directories

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix: string

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix: string

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: klog

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: io_buffer

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* doc: update AGENT.md

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* doc(etl): add ETL integration migration design plan

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix(libc): wrap noexcept in __cplusplus guard for C compilation

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(task): add ETL message and router ID registry

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(task): replace CloneFlags enum and cpu_affinity with etl::flags

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(interrupt): replace InterruptFunc pointer with etl::delegate

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(task): replace TaskStatus enum with etl::fsm state machine

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix(task): address code quality review findings for etl::fsm migration

- C1: Add ReapTask(current) for orphan tasks in Exit() to prevent TCB leak
- C2: Start FSM after default-constructing TCB in Clone() to avoid null deref
- I2: Use STATE_ID constant in StateExited::on_event(MsgReap)
- I3: Move GetStatus() implementation from header to .cpp file
- I4: Enqueue idle task in kReady state, then transition to kRunning
- M2: Restore dropped @todo SIGCHLD comment in exit.cpp
- M5: Add [[nodiscard]] attribute to GetStatus()

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(kernel): add tick and panic observer interfaces using etl::observer

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(kernel): add lifecycle and virtio message types for etl::message_router

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* docs(plans): add ETL migration implementation plan

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix: task_fsm

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: InterruptDelegate

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update include style

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: fsm

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: task_control_block

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* test: fix st

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* chore(docs): remove superseded etl-migration plan files

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(expected): add VirtIO/device error codes for device_framework unification

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device): add platform_config.hpp concrete impl for device_framework injection

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* build(device): use BEFORE in TARGET_INCLUDE_DIRECTORIES for platform_config override

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device_node): replace atomic<bool> with SpinLock-guarded bool, remove hand-rolled copy/move

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(df_bridge): remove DeviceStorage and ToKernelError, error types now unified

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(driver_registry): add etl::flat_map index for O(log N) platform driver lookup

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(virtio_blk_driver): remove Traits template param, use unified error and Storage types

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device): remove PlatformTraits template usage, unify error handling

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix(arch/riscv64): remove PlatformTraits template param from VirtioBlkDriver usage

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix(device): add kMaxSpinIterations to PlatformTraits; use TryBind() in DeviceManager::ProbeAll()

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* chore(submodule): bump device_framework to merged main (440bfe7)

device_framework feature/device-refactor merged into main:
- Traits template elimination via platform_config.hpp injection
- Unified error handling (PlatformErrorCode)
- Storage<T> freestanding optional added
- All tests updated for non-template API

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device): delete placeholder and redundant header files

Inline PlatformTraits struct into platform_config.hpp and delete
the now-redundant platform_traits.hpp. Also delete zero-caller
stubs: acpi_bus.hpp, pci_bus.hpp, virtio_messages.hpp.

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device): simplify device module — remove Driver concept and variant types

Replace template Register<D>() + Driver concept with plain DriverEntry
function-pointer struct. Flatten DeviceNode to pure data (remove variant
BusId, DeviceResource, DMA buffer, SpinLock). Move DMA allocation into
VirtioBlkDriver::Probe(). Delete df_bridge.hpp; introduce mmio_helper.hpp.

Net: ~1149 -> ~570 lines (~50% reduction), 13 -> 8 headers.
Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix(arch/riscv64,device): update interrupt_main and virtio_blk_driver for new driver API

- Replace DriverRegistry::GetDriverInstance<VirtioBlkDriver>() with
  VirtioBlkDriver::Instance() in interrupt_main.cpp (lines 100, 209)
- Remove unused #include "driver_registry.hpp" from interrupt_main.cpp
- Add missing #include "io_buffer.hpp" to virtio_blk_driver.hpp
- Fix kstd::unique_ptr<IoBuffer> -> etl::unique_ptr<IoBuffer>

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* docs(device): add device_framework integration design doc

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* chore(device): create driver/ subdirectory skeleton

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device): add traits.hpp inlined from device_framework

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device): add ops/device_ops_base.hpp inlined from device_framework

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device): add ops/char_device.hpp inlined from device_framework

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device): add ops/block_device_ops.hpp inlined from device_framework

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device): add detail/mmio_accessor.hpp inlined from device_framework

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device): add detail/storage.hpp inlined from device_framework

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device): add detail/uart_device.hpp inlined from device_framework

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device): add detail/ns16550a/ inlined from device_framework

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device): add detail/pl011/ inlined from device_framework

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device): add detail/virtio/defs.h + traits.hpp (task 11)

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device): add detail/virtio/transport/ (task 12)

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device): add detail/virtio/virt_queue/ inlined from device_framework (task 13)

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device): add detail/virtio/device/ inlined from device_framework

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device): add detail/acpi/ inlined from device_framework

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device): add pl011/acpi facade headers and update driver includes to inline headers

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(arch): replace device_framework includes with inlined driver headers

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* build: remove device_framework from CMake and .gitmodules

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* chore(device): remove device_framework submodule and platform_config.hpp hack

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix(device): add platform_config.hpp for inlined VirtIO driver and fix unit-test CMake link

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: apply clang-format to VirtIO device and transport headers

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* docs: remove plan

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device): replace raw array+ptr with etl::vector/flat_map in DriverRegistry

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device): migrate Ns16550aDriver to etl::delegate, remove DriverDescriptor

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device): migrate VirtioBlkDriver to etl::optional + etl::delegate

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device): delete detail/storage.hpp, superseded by etl::optional

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* docs(device): update AGENTS.md for ETL refactor

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* docs(device): fix duplicate section in AGENTS.md

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* docs: add device module refactor design document

Add design doc for src/device/ refactoring:
- Delete ~1000 lines of dead ops/ CRTP layer
- Replace VirtioBlkDriver with unified virtio::Probe() interface
- Runtime transport/device-type detection via std::variant
- Preserve detail/virtio/ structure for multi-device extensibility

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device): extract VirtioBlkVfsAdapter to dedicated header

Move VirtioBlkBlockDevice class (renamed VirtioBlkVfsAdapter) out of
device.cpp into its own header. No functional change.

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* test(device): add failing tests for VirtioDriver

Tests expect VirtioDriver::GetEntry() and MatchStatic() which will be
implemented in the next task (TDD).

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device): add unified VirtioDriver with runtime device-type dispatch

Replace VirtioBlkDriver with VirtioDriver that auto-detects VirtIO
device type (blk/net/gpu/...) at runtime by reading device_id register.
Caller (DeviceInit) no longer needs to know about VirtIO device types.

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* build(device): add virtio_driver.cpp to device library sources

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device): update DeviceInit to use unified VirtioDriver

Replace VirtioBlkDriver::GetEntry() with VirtioDriver::GetEntry().
DeviceInit no longer mentions specific VirtIO device types.

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device): ns16550a_driver include ns16550a.hpp directly

Remove dependency on ns16550a_device.hpp (CRTP wrapper, to be deleted).

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device): pl011_driver include pl011.hpp directly

Remove dependency on pl011_device.hpp (CRTP wrapper, to be deleted).

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device): delete dead ops/ CRTP layer and unused device wrappers

Remove ~1000 lines of dead code:
- driver/ops/ (device_ops_base.hpp, char_device.hpp, block_device_ops.hpp)
- driver/detail/uart_device.hpp
- driver/detail/ns16550a/ns16550a_device.hpp
- driver/detail/pl011/pl011_device.hpp
- driver/detail/virtio/device/virtio_blk_device.hpp
- driver/virtio_blk_driver.hpp (replaced by virtio_driver.hpp)

Also add GetIrq()/HandleInterrupt() to VirtioDriver and update
riscv64/interrupt_main.cpp to use VirtioDriver + Ns16550a directly.

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* docs(device): update AGENTS.md for new VirtioDriver architecture

- Document virtio_driver.cpp as the second .cpp exception
- Add VirtIO device extension guide (add device_id case only)
- Remove references to deleted ops/ layer and virtio_blk_driver

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* 3rd: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device): restructure drivers into per-driver subdirectories

- Each driver (ns16550a, pl011, acpi, virtio) now lives in its own
  subdirectory with an independent ADD_LIBRARY(xxx_driver INTERFACE)
  CMake target
- Delete detail/ directory; headers moved directly into driver
  subdirectories (ns16550a/, pl011/, acpi/, virtio/)
- device target changed from INTERFACE to STATIC with PRIVATE driver
  dependencies; consumers access hardware only through DeviceManager
- device CMakeLists: use explicit compile-only deps instead of
  kernel_link_libraries to avoid leaking -nostdlib/-T link.ld into
  unit-test link command
- Fix aarch64: add Pl011Device alias, HandleInterrupt stub, remove
  stale Open() call in early_console.cpp
- Fix virtio traits.hpp: change self-referential include to ../traits.hpp
- Arch code links driver targets explicitly as a documented exception
- All three arch builds and 163 unit tests pass

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: device

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device,fdt): add ForEachDeviceNode filter and split device_manager

- kernel_fdt.hpp: add ForEachDeviceNode() inline template that skips
  infrastructure nodes (interrupt-controller, #clock-cells, cpu,
  memory device_type) to suppress spurious 'no driver' log noise
- device_manager.hpp: extract ProbeAll/FindDevice/FindDevicesByType
  to device_manager.cpp; keep RegisterBus<B> template in header
- device_manager.cpp: implement the three methods with assert-based
  precondition checks and ProbeAll no_driver_count summary log
- virtio: fix missing newlines in klog::Debug format strings
- doc/plans: add design doc and implementation plan

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device): assert-harden mmio_helper and use ForEachDeviceNode

- driver_registry.hpp: replace mmio_base==0 error return in
  mmio_helper::Prepare with assert() — bad node is a driver bug, not
  a recoverable runtime condition; add #include <cassert>
- platform_bus.hpp: switch Enumerate to fdt_.ForEachDeviceNode so
  infrastructure nodes (interrupt-controller, clock, cpu, memory)
  are skipped before driver matching, eliminating 'no driver' noise

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: device

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: device

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(virtio): reorganize device/ into per-type subdirectories

Move virtio_blk.hpp, virtio_blk_defs.h, virtio_blk_vfs_adapter.hpp into
device/blk/, and placeholder headers into console/, net/, gpu/, input/.
Update all include paths and header guards accordingly.

device_initializer.hpp stays at device/ root as it is cross-device.

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(virtio): modernize VirtioBlk with std::array

Replace raw C arrays slots_[kMaxInflight] with std::array<RequestSlot, kMaxInflight>
and local IoVec[] with std::array<IoVec, kMaxSgElements> in DoEnqueue().
Replace static kNames[] with constexpr std::array<const char*, 4> in GetName().
Also zero-initialize slot_bitmap_ explicitly with {}.

Note: std::bitset was evaluated but omitted — std::bitset<N>::to_ulong()
references exception machinery (__throw_out_of_range_fmt) in GCC 14's
libstdc++, which is incompatible with this freestanding kernel build.

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* 3rd: update cpu_io

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: device

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat: mmio_accessor

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(arch/riscv64): add etl_putchar shim for ETL print support

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(arch/aarch64): add etl_putchar shim for ETL print support

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(arch/x86_64): add etl_putchar shim for ETL print support

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device): migrate klog calls to ETL format syntax

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(task): migrate klog calls to ETL format syntax

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(arch): migrate klog calls to ETL format syntax

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(src): migrate klog calls to ETL format syntax

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* docs: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* docs: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(klog): rewrite kernel_log.hpp with type-safe {} format syntax

- Replace printf-style %s/%d format strings with {}-based syntax
- Add KernelFmtStr<Args...> + KernelFormatString alias with type_identity_t
  for correct CTAD (mirrors std::format_string pattern)
- Add FormatArg() overloads for freestanding-safe single-arg printing
- Add LogFormat() recursive walker for format string processing
- Keep stream-style API (klog::info <<) unchanged
- Add ETL_FORCE_STD_INITIALIZER_LIST to prevent ETL/stdlib collision
  when ETL_NO_STL is set in freestanding mode
- Migrate clone.cpp and syscall.cpp to {} syntax
- Verified clean build on riscv64, aarch64, x86_64

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* docs: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(libc): remove nanoprintf, replace sk_printf with emit helpers

- Delete sk_printf/sk_snprintf/sk_vsnprintf API from sk_stdio.h and sk_stdio.c
- Add four __always_inline emit helpers: sk_emit_str, sk_emit_sint,
  sk_emit_uint, sk_emit_hex
- Migrate kernel_log.hpp, spinlock.hpp, kstd_iostream.cpp,
  kstd_libcxx.cpp, schedule.cpp, syscall.cpp to emit helpers
- Replace BmallocLogger with empty no-op implementation
- Remove nanoprintf git submodule and CMake integration
- cmake-lint skipped: pre-existing cmakelang internal crash (upstream bug)

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* 3rd: update cpu_io

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(libc): replace sk_putchar with etl_putchar

Remove the sk_putchar function pointer (and its unused ctx parameter).
etl_putchar(int c) — already defined per-arch in early_console.cpp —
becomes the sole low-level output primitive.

- Delete sk_stdio.c (contained only dummy_putchar + sk_putchar)
- Remove sk_stdio.c from libc CMakeLists
- sk_stdio.h declares etl_putchar; sk_emit_* helpers call it directly
- riscv64/early_console: drop EarlyConsole struct (SBI always ready)
- aarch64/x86_64 early_console: collapse console_putchar into etl_putchar
- Replace all sk_putchar(c, nullptr) -> etl_putchar(c) across 8 files

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(klog): simplify kernel_log — 8 complexity fixes

- Support {:x}/{:#x}/{:X}/{:#X} format specifiers for integers
- Unify type printing: operator<< delegates to FormatArg
- Extract EmitHeader<Level>() to eliminate duplicated prefix code
- Remove redundant if constexpr level checks in struct constructors
- Replace throw with non-constexpr call in consteval context (freestanding safe)
- Fix DebugBlob: use if constexpr only, remove #ifdef SIMPLEKERNEL_DEBUG
- Rename LogStarter -> LogStream for clarity
- Add auto-newline in LogEmit/~LogLine, strip trailing backslash n from all
  call sites (63 files: src/**/*.cpp, src/**/*.hpp, tests/**/*.cpp)

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: replace nanoprintf with etl

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* docs: remove plans

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat: remove kstd::ostream

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: sk_print_str

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: replace __attribute__ with [[xxx]]

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: replace __attribute__ with [[xxx]]

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix: backtrace

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix: virtio

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: device

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device): unify driver singletons to etl::singleton

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: device

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* docs: remove etl docs

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix(device): resolve singleton alias forward-reference in GetEntry()

Replace XxxSingleton::instance() with etl::singleton<Xxx>::instance() inside GetEntry() where the type alias is not yet declared. Affects Pl011Driver, Ns16550aDriver, and VirtioDriver.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(device): add DmaRegion type and IoBuffer::ToDmaRegion()

Introduce DmaRegion{virt, phys, size} value type, VirtToPhysFunc callback, and IdentityVirtToPhys default in io_buffer.hpp. Add ToDmaRegion() to IoBuffer for converting buffers to DMA-ready regions. Includes 8 GoogleTest unit tests and implementation plan.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(device): replace void* DMA with DmaRegion + VirtToPhys abstraction

Refactor SplitVirtqueue, VirtioBlk, and VirtioDriver to use DmaRegion instead of raw void*/uintptr_t pairs. VirtioBlk::Create() now accepts separate vq_dma and slot_dma regions with a VirtToPhysFunc callback, eliminating hardcoded identity-mapping assumptions. RequestSlot memory is allocated from a dedicated DMA buffer for device-accessible physical addresses.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: sk_print_str

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: device

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat(log): add per-CPU lock-free LogLineRaw/LogStreamRaw interfaces

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix(arch): use lock-free klog::raw_err in DumpStack to prevent deadlock

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: klog

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: klog

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor: klog

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* 3rd: add stb and EasyLogger

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* 3rd: add stb and EasyLogger

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* 3rd: add stb and EasyLogger

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* 3rd: add stb and EasyLogger

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* docs(log): add MPMC log refactor design and implementation plan

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(log): rewrite kernel_log.hpp with MPMC lock-free queue

Replace SpinLock-based stream logging with Vyukov lock-free MPMC queue.

New API: klog::Info/Warn/Err/Debug (printf-style), klog::Flush, klog::RawPut.

Remove: LogLine, LogLineRaw, LogStream, LogStreamRaw, DebugBlob, klog::hex/HEX.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(log): migrate src/main.cpp to new klog API

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(log): migrate src/arch/x86_64/ to new klog API

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(log): migrate src/arch/riscv64/ to new klog API

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(log): migrate src/arch/aarch64/ to new klog API

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(log): migrate src/memory/ to new klog API

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(log): migrate src/device/ to new klog API

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(log): migrate src/task/ to new klog API

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(log): migrate src/filesystem/ to new klog API

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(log): migrate remaining headers and syscall to new klog API

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* refactor(log): update commented-out klog calls in spinlock.hpp to new API

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix(log): replace __always_inline with inline on variadic klog functions

GCC cannot inline functions using variable argument lists (...).
Change Debug(), Info(), Warn(), Err() from __always_inline to inline.
Flush() and RawPut() remain __always_inline as they are non-variadic.

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix(log): add missing cpu_io.h include for GetCurrentCoreId

kernel_log.hpp uses cpu_io::GetCurrentCoreId() but did not include
the header, causing 'cpu_io has not been declared' build errors.

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat: mpsc log

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat: etl format

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix: etl format

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat: log with core id

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat: log with core id

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* feat: working on smp

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* 3rd: update etl

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* 3rd: update etl

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix: add boot_task

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix: move TimerInit to main

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix: move TimerInit to main

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* doc: update AGENTS.md

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: use pragma once

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style(arch,filesystem,memory): update headers to coding standards

- Add trailing return types, [[nodiscard]], @brief, brace init, constructor groups
- Arch: interrupt.h (riscv64/aarch64/x86_64), plic.h, gic.h, apic.h, io_apic.h, local_apic.h, sipi.h
- Filesystem: file_descriptor.hpp, vfs.hpp, vfs_types.hpp, mount.hpp, vfs_internal.hpp, ramfs.hpp, fatfs.hpp
- Memory: virtual_memory.hpp
- Build verified on riscv64 and x86_64

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: use trailing return types in .cpp and arch.h

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* docs: update AGENTS.md

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* test: fix st

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* style: update

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* test: fix st

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* test: fix st

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* test: fix st

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* docs: update AGENTS.md

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix: warnning

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

* fix(multi): address Copilot review findings across IO APIC, VFS, device, and DMA

- io_apic: add early return after OOB IRQ check in SetIrqRedirection/MaskIrq/UnmaskIrq
- mkdir: add NUL-termination after strncpy on dentry name
- lookup: replace broken mount-point loop with FindByMountDentry
- file_descriptor: fix open_count_ over-counting in SetupStandardFiles
- io_buffer: fix size_t overflow in SubRegion bounds check
- open/mkdir: reject path components exceeding buffer sizes
- file_descriptor: use address-based lock ordering in move-assignment
- virtio_driver: pass slot_align to IoBuffer for consistency
- diskio: add nullptr guard for buff in disk_ioctl

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>

---------

Signed-off-by: Niu Zhihong <zhihong@nzhnb.com>
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

Author: MRNIU

.github/ISSUE_TEMPLATE/bug_report.md

@@ -28,7 +28,7 @@ If applicable, add screenshots to help explain your problem.
  - Compile tools: [e.g. i386-elf-gcc i386-elf-ld]
  - Emulator: [e.g. Bochs 2.6.9]
  - Branch: [e.g. TODO]
- - Any modifications to tools/env.sh: 
+ - Any modifications to tools/env.sh:
 
 **Additional context**
 Add any other context about the problem here.

.github/ISSUE_TEMPLATE/help.md

@@ -12,7 +12,7 @@ assignees: ''
  - Compile tools: [e.g. i386-elf-gcc i386-elf-ld]
  - Emulator: [e.g. Bochs 2.6.9]
  - Branch: [e.g. TODO]
- - Any modifications to tools/env.sh: 
+ - Any modifications to tools/env.sh:
 
 **Describe your question**
 A clear and concise description of what the question is.

.github/copilot-instructions.md

@@ -0,0 +1 @@
+../AGENTS.md

.github/copilot-instructions.md

@@ -32,7 +32,7 @@ jobs:
           options: -v ${{ github.workspace }}:/root -e CMAKE_BUILD_TYPE=${{ env.CMAKE_BUILD_TYPE }}
           run: |
             cmake --preset=build_x86_64
-            cmake --build build_x86_64 --target SimpleKernel unit-test coverage doc
+            cmake --build build_x86_64 --target SimpleKernel unit-test coverage docs
 
       - name: riscv64
         uses: addnab/docker-run-action@v3
@@ -63,7 +63,7 @@ jobs:
         uses: peaceiris/actions-gh-pages@v3
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
-          publish_dir: ${{ github.workspace }}/doc/html
+          publish_dir: ${{ github.workspace }}/docs/html
 
       # - name: Super-Linter
       #   uses: super-linter/super-linter@v7.2.0

.github/workflows/workflow.yml

@@ -5,7 +5,7 @@
 build_aarch64
 build_riscv64
 build_x86_64
-doc/html
+docs/html
 .vscode/*
 !.vscode/tasks.json
 !.vscode/launch.json
@@ -15,3 +15,4 @@ Doxyfile
 *.objdump
 *.elf
 .pre-commit-config.yaml
+.worktrees/

.gitignore

@@ -28,12 +28,18 @@
 [submodule "3rd/u-boot"]
 	path = 3rd/u-boot
 	url = https://github.com/u-boot/u-boot.git
-[submodule "3rd/nanoprintf"]
-	path = 3rd/nanoprintf
-	url = https://github.com/charlesnicholson/nanoprintf.git
 [submodule "3rd/bmalloc"]
 	path = 3rd/bmalloc
 	url = https://github.com/MRNIU/bmalloc.git
 [submodule "3rd/MPMCQueue"]
 	path = 3rd/MPMCQueue
 	url = https://github.com/MRNIU/MPMCQueue.git
+[submodule "3rd/fatfs"]
+	path = 3rd/fatfs
+	url = https://github.com/abbrev/fatfs.git
+[submodule "3rd/etl"]
+	path = 3rd/etl
+	url = https://github.com/ETLCPP/etl.git
+[submodule "3rd/EasyLogger"]
+	path = 3rd/EasyLogger
+	url = https://github.com/armink/EasyLogger.git

.gitmodules

@@ -1,20 +1,21 @@
 # Copyright The MPMCQueue Contributors
 
-cmake_minimum_required(VERSION 3.20)
+CMAKE_MINIMUM_REQUIRED (VERSION 3.20)
 
-project(MPMCQueue
-    DESCRIPTION "Multi-Producer Multi-Consumer Lock-Free Queue for Freestanding C++26"
-    LANGUAGES CXX
-)
+PROJECT (
+    MPMCQueue
+    DESCRIPTION
+        "Multi-Producer Multi-Consumer Lock-Free Queue for Freestanding C++26"
+    LANGUAGES CXX)
 
-if (${PROJECT_SOURCE_DIR} STREQUAL ${PROJECT_BINARY_DIR})
-    message(
-            FATAL_ERROR
+IF(${PROJECT_SOURCE_DIR} STREQUAL ${PROJECT_BINARY_DIR})
+    MESSAGE (
+        FATAL_ERROR
             "In-source builds not allowed. Please make a new directory (called a build directory) and run CMake from there."
     )
-endif ()
+ENDIF()
 
 ADD_LIBRARY (${PROJECT_NAME} INTERFACE)
 TARGET_INCLUDE_DIRECTORIES (${PROJECT_NAME} INTERFACE include)
 
-add_subdirectory(${PROJECT_SOURCE_DIR}/test)
+ADD_SUBDIRECTORY (${PROJECT_SOURCE_DIR}/test)

3rd/EasyLogger

@@ -65,4 +65,4 @@
       "description": "build"
     }
   ]
-}
+}