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Kernel/ACPI: Make most of StaticParsing methods to be platform-agnostic

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Most of the ACPI static parsing methods (methods that can be called
without initializing a full AML parser) are not tied to any specific
platform or CPU architecture.

The only method that is platform-specific is the one that finds the RSDP
structure. Thus, each CPU architecture/platform needs to implement it.
This means that now aarch64 can implement its own method to find the
ACPI RSDP structure, which would be hooked into the rest of the ACPI
code elegantly, but for now I just added a FIXME and that method returns
empty value of Optional<PhysicalAddress>.
This commit is contained in:
Liav A 2023-06-09 22:50:11 +03:00 • committed by Jelle Raaijmakers
parent be16a91aec
commit 428afca32b
11 changed files with 211 additions and 133 deletions
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57
Kernel/Arch/x86_64/Firmware/ACPI/StaticParsing.cpp Normal file
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/*
* Copyright (c) 2023, Liav A. <liavalb@hotmail.co.il>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <Kernel/Firmware/ACPI/StaticParsing.h>
#include <Kernel/Firmware/BIOS.h>
#include <Kernel/Memory/MemoryManager.h>
namespace Kernel::ACPI::StaticParsing {
// https://uefi.org/specs/ACPI/6.4/05_ACPI_Software_Programming_Model/ACPI_Software_Programming_Model.html#finding-the-rsdp-on-ia-pc-systems
ErrorOr<Optional<PhysicalAddress>> find_rsdp_in_platform_specific_memory_locations()
{
constexpr auto signature = "RSD PTR "sv;
auto ebda_or_error = map_ebda();
if (!ebda_or_error.is_error()) {
auto rsdp = ebda_or_error.value().find_chunk_starting_with(signature, 16);
if (rsdp.has_value())
return rsdp;
}
auto bios_or_error = map_bios();
if (!bios_or_error.is_error()) {
auto rsdp = bios_or_error.value().find_chunk_starting_with(signature, 16);
if (rsdp.has_value())
return rsdp;
}
// On some systems the RSDP may be located in ACPI NVS or reclaimable memory regions
Optional<PhysicalAddress> rsdp;
MM.for_each_physical_memory_range([&](auto& memory_range) {
if (!(memory_range.type == Memory::PhysicalMemoryRangeType::ACPI_NVS || memory_range.type == Memory::PhysicalMemoryRangeType::ACPI_Reclaimable))
return IterationDecision::Continue;
Memory::MappedROM mapping;
auto region_size_or_error = Memory::page_round_up(memory_range.length);
if (region_size_or_error.is_error())
return IterationDecision::Continue;
auto region_or_error = MM.allocate_kernel_region(memory_range.start, region_size_or_error.value(), {}, Memory::Region::Access::Read);
if (region_or_error.is_error())
return IterationDecision::Continue;
mapping.region = region_or_error.release_value();
mapping.offset = memory_range.start.offset_in_page();
mapping.size = memory_range.length;
mapping.paddr = memory_range.start;
rsdp = mapping.find_chunk_starting_with(signature, 16);
if (rsdp.has_value())
return IterationDecision::Break;
return IterationDecision::Continue;
});
return rsdp;
}
}