MaxOS::hardwarecommunication::AdvancedConfigurationAndPowerInterface Class Reference

Handles ACPI table parsing and retrieval. More...

#include <acpi.h>

Public Member Functions
	AdvancedConfigurationAndPowerInterface (system::Multiboot *multiboot)
	Construct a new Advanced Configuration And Power Interface object. Maps the ACPI headers and tables into the higher half.
acpi_sdt_header_t *	find (const char *signature)
	Finds a table with the given signature.

Detailed Description

Handles ACPI table parsing and retrieval.

Definition at line 99 of file acpi.h.

Constructor & Destructor Documentation

AdvancedConfigurationAndPowerInterface()

AdvancedConfigurationAndPowerInterface::AdvancedConfigurationAndPowerInterface ( system::Multiboot *  multiboot )

explicit

Construct a new Advanced Configuration And Power Interface object. Maps the ACPI headers and tables into the higher half.

Parameters

multiboot

The multiboot information structure to get the ACPI information from

Definition at line 23 of file acpi.cpp.

: m_header(nullptr) {
 
    Logger::INFO() << "Setting up ACPI\n";
 
    // If the new ACPI is not supported, panic
    ASSERT(multiboot->new_acpi() != nullptr || multiboot->old_acpi() != nullptr, "No ACPI found!");
 
    // Check if the new ACPI is supported
    m_using_new_acpi = multiboot->old_acpi() == nullptr;
    Logger::DEBUG() << "CPU Supports " << (m_using_new_acpi ? "New" : "Old") << " ACPI\n";
 
    if(m_using_new_acpi)
        m_rsdp2 = (RSDPDescriptor2*) (multiboot->new_acpi() + 1);
    else
        m_rsdp = (RSDPDescriptor*) (multiboot->old_acpi() + 1);
 
    // Map the XSDT/RSDT
    uint64_t physical_address = m_using_new_acpi ? m_rsdp2->xsdt_address : m_rsdp->rsdt_address;
    void* virtual_address = map_descriptor(physical_address);
    ASSERT(virtual_address != nullptr, "Failed to map ACPI table");
    Logger::DEBUG() << "XSDT/RSDT: physical: 0x" << physical_address << ", virtual: 0x" << (uint64_t) virtual_address
                    << "\n";
 
    // Load
    if(m_using_new_acpi)
        m_xsdt = (XSDT*) virtual_address;
    else
        m_rsdt = (RSDT*) virtual_address;
 
    // Map the Tables
    Logger::DEBUG() << "Mapping ACPI Tables\n";
    map_tables(m_using_new_acpi ? sizeof(uint64_t) : sizeof(uint32_t));
 
    // Check if the checksum is valid
    ASSERT(valid_checksum(), "ACPI: Invalid checksum!");
}

References ASSERT, MaxOS::Logger::DEBUG(), and MaxOS::Logger::INFO().

Member Function Documentation

find()

ACPISDTHeader * AdvancedConfigurationAndPowerInterface::find

(

const char *

signature

)

Finds a table with the given signature.

Parameters

signature

The signature to search for

Returns

The table with the given signature, or nullptr if not found

Definition at line 163 of file acpi.cpp.

                                                                                 {
 
    // Get the number of entries
    size_t entries = (m_header->length - sizeof(ACPISDTHeader)) / sizeof(uint32_t);
    if(m_using_new_acpi) entries = (m_header->length - sizeof(ACPISDTHeader)) / sizeof(uint64_t);
 
    // Loop through all the entries
    for(size_t i = 0; i < entries; ++i) {
 
        // Get the entry
        auto* header = (ACPISDTHeader*) (m_using_new_acpi ? m_xsdt->pointers[i] : get_rsdt_pointer(i));
 
        // Move the header to the higher half
        header = (ACPISDTHeader*) PhysicalMemoryManager::to_io_region((uint64_t) header);
 
        // Check if the signature matches
        if(strncmp(header->signature, signature, 4))
            return header;
    }
 
    // Return null if no entry was found
    return nullptr;
}

References MaxOS::hardwarecommunication::XSDT::pointers, strncmp(), and MaxOS::memory::PhysicalMemoryManager::to_io_region().

Referenced by MaxOS::hardwarecommunication::IOAPIC::IOAPIC().

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The documentation for this class was generated from the following files:

• /home/runner/work/MaxOS/MaxOS/kernel/include/hardwarecommunication/acpi.h
• /home/runner/work/MaxOS/MaxOS/kernel/src/hardwarecommunication/acpi.cpp