From f50815110789a0f8f6e5ca66ffd49b26578791a9 Mon Sep 17 00:00:00 2001 From: Felix Morgner Date: Mon, 6 Apr 2026 18:43:28 +0200 Subject: kernel: generalize CPU discovery --- arch/x86_64/CMakeLists.txt | 1 + arch/x86_64/kapi/acpi.cpp | 13 -------- arch/x86_64/kapi/platform.cpp | 70 ++++++++++++++++++++++++++++++++++++++++++ kapi/include/kapi/acpi.hpp | 4 --- kapi/include/kapi/platform.hpp | 37 ++++++++++++++++++++++ kernel/CMakeLists.txt | 1 + kernel/kapi/devices.cpp | 11 ++----- kernel/kapi/platform.cpp | 32 +++++++++++++++++++ kernel/src/devices/cpu.cpp | 58 ++-------------------------------- 9 files changed, 147 insertions(+), 80 deletions(-) create mode 100644 arch/x86_64/kapi/platform.cpp create mode 100644 kapi/include/kapi/platform.hpp create mode 100644 kernel/kapi/platform.cpp diff --git a/arch/x86_64/CMakeLists.txt b/arch/x86_64/CMakeLists.txt index 62a2aad..87cb98c 100644 --- a/arch/x86_64/CMakeLists.txt +++ b/arch/x86_64/CMakeLists.txt @@ -19,6 +19,7 @@ target_sources("x86_64" PRIVATE "kapi/devices.cpp" "kapi/interrupts.cpp" "kapi/memory.cpp" + "kapi/platform.cpp" "kapi/system.cpp" # CPU Initialization diff --git a/arch/x86_64/kapi/acpi.cpp b/arch/x86_64/kapi/acpi.cpp index 9766154..ec38aee 100644 --- a/arch/x86_64/kapi/acpi.cpp +++ b/arch/x86_64/kapi/acpi.cpp @@ -1,16 +1,9 @@ #include "kapi/acpi.hpp" -#include "kapi/devices.hpp" -#include "kapi/memory.hpp" - #include "arch/boot/boot.hpp" -#include "arch/devices/local_apic.hpp" #include -#include -#include - namespace kapi::acpi { @@ -34,10 +27,4 @@ namespace kapi::acpi return kstd::make_observer(system_description_pointer); } - auto create_local_interrupt_controller(std::size_t major, std::size_t minor, std::uint64_t hardware_id, - memory::physical_address address) -> kstd::unique_ptr - { - return kstd::make_unique(major, minor, hardware_id, address); - } - } // namespace kapi::acpi \ No newline at end of file diff --git a/arch/x86_64/kapi/platform.cpp b/arch/x86_64/kapi/platform.cpp new file mode 100644 index 0000000..2e7c7e4 --- /dev/null +++ b/arch/x86_64/kapi/platform.cpp @@ -0,0 +1,70 @@ +#include "kapi/platform.hpp" + +#include "kapi/acpi.hpp" +#include "kapi/devices.hpp" +#include "kapi/memory.hpp" + +#include "arch/devices/local_apic.hpp" + +#include +#include + +#include +#include + +namespace kapi::platform +{ + + namespace + { + constexpr auto default_lapic_address = kapi::memory::physical_address{0xFEE0'0000}; + } + + auto discover_cpu_topology(kapi::devices::bus & bus) -> bool + { + auto madt = kapi::acpi::get_table("APIC"); + if (!madt) + { + kstd::println("[x86_64:PLT] Failed to find ACPI APIC table"); + return false; + } + + auto const * current = reinterpret_cast(madt.get()) + sizeof(kapi::acpi::madt_header); + auto const * end = reinterpret_cast(madt.get()) + madt->length(); + + auto bsp_found = false; + auto core_count = 0uz; + + while (current < end) + { + auto const * sub_table = reinterpret_cast(current); + if (sub_table->type() == 0) + { + auto const * local_apic = reinterpret_cast(sub_table); + if (local_apic->flags() & 0b11) + { + auto is_bsp = !bsp_found; + bsp_found = true; + + if (kapi::platform::cpu_detected(bus, local_apic->processor_id(), is_bsp)) + { + ++core_count; + } + } + } + + current += sub_table->length(); + } + + kstd::println("[x86_64:PLT] Found {} CPU cores", core_count); + + return core_count > 0; + } + + auto create_core_interrupt_controller(std::size_t major, std::size_t minor, std::uint64_t hardware_id) + -> kstd::unique_ptr + { + return kstd::make_unique(major, minor, hardware_id, default_lapic_address); + } + +} // namespace kapi::platform \ No newline at end of file diff --git a/kapi/include/kapi/acpi.hpp b/kapi/include/kapi/acpi.hpp index 5d55d08..75b6c48 100644 --- a/kapi/include/kapi/acpi.hpp +++ b/kapi/include/kapi/acpi.hpp @@ -1,7 +1,6 @@ #ifndef TEACHOS_KAPI_ACPI_HPP #define TEACHOS_KAPI_ACPI_HPP -#include "kapi/devices.hpp" #include "kapi/memory.hpp" #include @@ -128,9 +127,6 @@ namespace kapi::acpi auto get_root_pointer() -> kstd::observer_ptr; - auto create_local_interrupt_controller(std::size_t major, std::size_t minor, std::uint64_t hardware_id, - memory::physical_address address) -> kstd::unique_ptr; - //! @} } // namespace kapi::acpi diff --git a/kapi/include/kapi/platform.hpp b/kapi/include/kapi/platform.hpp new file mode 100644 index 0000000..6aae795 --- /dev/null +++ b/kapi/include/kapi/platform.hpp @@ -0,0 +1,37 @@ +#ifndef TEACHOS_KAPI_PLATFORM_HPP +#define TEACHOS_KAPI_PLATFORM_HPP + +#include "kapi/devices.hpp" + +#include + +#include +#include + +namespace kapi::platform +{ + + //! @addtogroup kapi-platform-kernel-defined + //! @{ + + auto cpu_detected(kapi::devices::bus & bus, std::uint64_t hardware_id, bool is_bsp) -> bool; + + //! @} + + //! @addtogroup kapi-platform-platform-defined + //! @{ + + //! Discover the CPU topology of the platform and attach it to the given CPU bus. + //! + //! @param bus The bus to attach the CPU topology to. + //! @return true iff. the CPU topology was discovered successfully, false otherwise. + auto discover_cpu_topology(kapi::devices::bus & bus) -> bool; + + auto create_core_interrupt_controller(std::size_t major, std::size_t minor, std::uint64_t hardware_id) + -> kstd::unique_ptr; + + //! @} + +} // namespace kapi::platform + +#endif \ No newline at end of file diff --git a/kernel/CMakeLists.txt b/kernel/CMakeLists.txt index 6e081bd..22513ea 100644 --- a/kernel/CMakeLists.txt +++ b/kernel/CMakeLists.txt @@ -9,6 +9,7 @@ add_library("kernel_objs" OBJECT "kapi/devices/device.cpp" "kapi/interrupts.cpp" "kapi/memory.cpp" + "kapi/platform.cpp" "kapi/system.cpp" # KSTD OS Implementation diff --git a/kernel/kapi/devices.cpp b/kernel/kapi/devices.cpp index b2911b0..dad1fe4 100644 --- a/kernel/kapi/devices.cpp +++ b/kernel/kapi/devices.cpp @@ -1,6 +1,5 @@ #include "kapi/devices.hpp" -#include "kapi/acpi.hpp" #include "kapi/system.hpp" #include "kernel/devices/cpu.hpp" @@ -38,13 +37,9 @@ namespace kapi::devices register_device(bus); bus.init(); - auto madt = kapi::acpi::get_table("APIC"); - if (madt) - { - auto cpu_major = allocate_major_number(); - auto cpu = kstd::make_unique(cpu_major); - bus.add_child(std::move(cpu)); - } + auto cpu_major = allocate_major_number(); + auto cpu = kstd::make_unique(cpu_major); + bus.add_child(std::move(cpu)); } auto get_root_bus() -> bus & diff --git a/kernel/kapi/platform.cpp b/kernel/kapi/platform.cpp new file mode 100644 index 0000000..deb72de --- /dev/null +++ b/kernel/kapi/platform.cpp @@ -0,0 +1,32 @@ +#include "kapi/platform.hpp" + +#include "kapi/devices.hpp" + +#include "kernel/devices/cpu.hpp" + +#include + +#include +#include + +namespace kapi::platform +{ + + auto cpu_detected(kapi::devices::bus & bus, std::uint64_t hardware_id, bool is_bsp) -> bool + { + auto static const core_major = kapi::devices::allocate_major_number(); + auto static const interrupt_controller_major = kapi::devices::allocate_major_number(); + auto static core_index = 0uz; + + auto core = kstd::make_unique(core_major, core_index, hardware_id, is_bsp); + auto lapic = kapi::platform::create_core_interrupt_controller(interrupt_controller_major, core_index, hardware_id); + + core->add_child(std::move(lapic)); + bus.add_child(std::move(core)); + + ++core_index; + + return true; + } + +} // namespace kapi::platform \ No newline at end of file diff --git a/kernel/src/devices/cpu.cpp b/kernel/src/devices/cpu.cpp index 7147368..eb10d74 100644 --- a/kernel/src/devices/cpu.cpp +++ b/kernel/src/devices/cpu.cpp @@ -1,64 +1,16 @@ #include "kernel/devices/cpu.hpp" -#include "kapi/acpi.hpp" #include "kapi/devices.hpp" +#include "kapi/platform.hpp" -#include #include #include #include -#include namespace kernel::devices { - namespace - { - - auto process_madt(kstd::observer_ptr madt, kapi::devices::bus & cpu) -> void - { - auto static const core_major = kapi::devices::allocate_major_number(); - auto static const lapic_major = kapi::devices::allocate_major_number(); - - auto lapic_address = madt->local_interrupt_controller_address(); - - auto const * current = reinterpret_cast(madt.get()) + sizeof(kapi::acpi::madt_header); - auto const * end = reinterpret_cast(madt.get()) + madt->length(); - - auto bsp_found = false; - auto core_index = 0; - - while (current < end) - { - auto const * sub_table = reinterpret_cast(current); - if (sub_table->type() == 0) - { - auto const * local_apic = reinterpret_cast(sub_table); - if (local_apic->flags() & 0b11) - { - auto is_bsp = !bsp_found; - bsp_found = true; - - auto apic_id = local_apic->apic_id(); - auto core = kstd::make_unique(core_major, core_index, apic_id, is_bsp); - auto lapic = kapi::acpi::create_local_interrupt_controller(lapic_major, core_index, apic_id, lapic_address); - - core->add_child(std::move(lapic)); - cpu.add_child(std::move(core)); - - ++core_index; - } - } - - current += sub_table->length(); - } - - kstd::println("[OS:DEV] Discovered {} CPU cores", core_index); - } - - } // namespace - cpu::core::core(std::size_t major_number, std::size_t minor_number, std::uint64_t hardware_id, bool is_bsp) : kapi::devices::bus{major_number, minor_number, "cpu_core"} , m_hardware_id{hardware_id} @@ -81,16 +33,12 @@ namespace kernel::devices auto cpu::probe() -> bool { - auto madt = kapi::acpi::get_table("APIC"); - if (!madt) + if (!kapi::platform::discover_cpu_topology(*this)) { - kstd::println("[OS:DEV] Failed to find ACPI APIC table"); + kstd::println("[OS:DEV] Failed to discover CPU topology"); return false; } - auto madt_header = static_cast(madt.get()); - process_madt(kstd::make_observer(madt_header), *this); - return true; } -- cgit v1.2.3