ladybird/Kernel/Firmware/BIOS.cpp
Liav A 33f033066c Kernel: Unify BIOS and ACPI components in the SysFS firmware directory
Both should reside in the SysFS firmware directory which is normally
located in /sys/firmware.
Also, apply some OOM-safety patterns when creating the BIOS and ACPI
directories.
2021-09-12 11:52:16 +02:00

183 lines
7 KiB
C++

/*
* Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2021, Liav A. <liavalb@hotmail.co.il>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/StringView.h>
#include <Kernel/FileSystem/OpenFileDescription.h>
#include <Kernel/Firmware/BIOS.h>
#include <Kernel/KBufferBuilder.h>
#include <Kernel/Memory/MemoryManager.h>
#include <Kernel/Memory/TypedMapping.h>
#include <Kernel/Sections.h>
namespace Kernel {
#define SMBIOS_BASE_SEARCH_ADDR 0xf0000
#define SMBIOS_END_SEARCH_ADDR 0xfffff
#define SMBIOS_SEARCH_AREA_SIZE (SMBIOS_END_SEARCH_ADDR - SMBIOS_BASE_SEARCH_ADDR)
UNMAP_AFTER_INIT NonnullRefPtr<DMIEntryPointExposedBlob> DMIEntryPointExposedBlob::create(PhysicalAddress dmi_entry_point, size_t blob_size)
{
return adopt_ref(*new (nothrow) DMIEntryPointExposedBlob(dmi_entry_point, blob_size));
}
UNMAP_AFTER_INIT BIOSSysFSComponent::BIOSSysFSComponent(String name)
: SysFSComponent(name)
{
}
KResultOr<size_t> BIOSSysFSComponent::read_bytes(off_t offset, size_t count, UserOrKernelBuffer& buffer, OpenFileDescription*) const
{
auto blob = TRY(try_to_generate_buffer());
if ((size_t)offset >= blob->size())
return KSuccess;
ssize_t nread = min(static_cast<off_t>(blob->size() - offset), static_cast<off_t>(count));
TRY(buffer.write(blob->data() + offset, nread));
return nread;
}
UNMAP_AFTER_INIT DMIEntryPointExposedBlob::DMIEntryPointExposedBlob(PhysicalAddress dmi_entry_point, size_t blob_size)
: BIOSSysFSComponent("smbios_entry_point")
, m_dmi_entry_point(dmi_entry_point)
, m_dmi_entry_point_length(blob_size)
{
}
KResultOr<NonnullOwnPtr<KBuffer>> DMIEntryPointExposedBlob::try_to_generate_buffer() const
{
auto dmi_blob = Memory::map_typed<u8>((m_dmi_entry_point), m_dmi_entry_point_length);
return KBuffer::try_create_with_bytes(Span<u8> { dmi_blob.ptr(), m_dmi_entry_point_length });
}
UNMAP_AFTER_INIT NonnullRefPtr<SMBIOSExposedTable> SMBIOSExposedTable::create(PhysicalAddress smbios_structure_table, size_t smbios_structure_table_length)
{
return adopt_ref(*new (nothrow) SMBIOSExposedTable(smbios_structure_table, smbios_structure_table_length));
}
UNMAP_AFTER_INIT SMBIOSExposedTable::SMBIOSExposedTable(PhysicalAddress smbios_structure_table, size_t smbios_structure_table_length)
: BIOSSysFSComponent("DMI")
, m_smbios_structure_table(smbios_structure_table)
, m_smbios_structure_table_length(smbios_structure_table_length)
{
}
KResultOr<NonnullOwnPtr<KBuffer>> SMBIOSExposedTable::try_to_generate_buffer() const
{
auto dmi_blob = Memory::map_typed<u8>((m_smbios_structure_table), m_smbios_structure_table_length);
return KBuffer::try_create_with_bytes(Span<u8> { dmi_blob.ptr(), m_smbios_structure_table_length });
}
UNMAP_AFTER_INIT void BIOSSysFSDirectory::set_dmi_64_bit_entry_initialization_values()
{
dbgln("BIOSSysFSDirectory: SMBIOS 64bit Entry point @ {}", m_dmi_entry_point);
auto smbios_entry = Memory::map_typed<SMBIOS::EntryPoint64bit>(m_dmi_entry_point, SMBIOS_SEARCH_AREA_SIZE);
m_smbios_structure_table = PhysicalAddress(smbios_entry.ptr()->table_ptr);
m_dmi_entry_point_length = smbios_entry.ptr()->length;
m_smbios_structure_table_length = smbios_entry.ptr()->table_maximum_size;
}
UNMAP_AFTER_INIT void BIOSSysFSDirectory::set_dmi_32_bit_entry_initialization_values()
{
dbgln("BIOSSysFSDirectory: SMBIOS 32bit Entry point @ {}", m_dmi_entry_point);
auto smbios_entry = Memory::map_typed<SMBIOS::EntryPoint32bit>(m_dmi_entry_point, SMBIOS_SEARCH_AREA_SIZE);
m_smbios_structure_table = PhysicalAddress(smbios_entry.ptr()->legacy_structure.smbios_table_ptr);
m_dmi_entry_point_length = smbios_entry.ptr()->length;
m_smbios_structure_table_length = smbios_entry.ptr()->legacy_structure.smboios_table_length;
}
UNMAP_AFTER_INIT KResultOr<NonnullRefPtr<BIOSSysFSDirectory>> BIOSSysFSDirectory::try_create(FirmwareSysFSDirectory& firmware_directory)
{
auto bios_directory = TRY(adopt_nonnull_ref_or_enomem(new (nothrow) BIOSSysFSDirectory(firmware_directory)));
bios_directory->create_components();
return bios_directory;
}
void BIOSSysFSDirectory::create_components()
{
if (m_dmi_entry_point.is_null() || m_smbios_structure_table.is_null())
return;
if (m_dmi_entry_point_length == 0) {
dbgln("BIOSSysFSDirectory: invalid dmi entry length");
return;
}
if (m_smbios_structure_table_length == 0) {
dbgln("BIOSSysFSDirectory: invalid smbios structure table length");
return;
}
auto dmi_entry_point = DMIEntryPointExposedBlob::create(m_dmi_entry_point, m_dmi_entry_point_length);
m_components.append(dmi_entry_point);
auto smbios_table = SMBIOSExposedTable::create(m_smbios_structure_table, m_smbios_structure_table_length);
m_components.append(smbios_table);
}
UNMAP_AFTER_INIT void BIOSSysFSDirectory::initialize_dmi_exposer()
{
VERIFY(!(m_dmi_entry_point.is_null()));
if (m_using_64bit_dmi_entry_point) {
set_dmi_64_bit_entry_initialization_values();
} else {
set_dmi_32_bit_entry_initialization_values();
}
dbgln("BIOSSysFSDirectory: Data table @ {}", m_smbios_structure_table);
}
UNMAP_AFTER_INIT BIOSSysFSDirectory::BIOSSysFSDirectory(FirmwareSysFSDirectory& firmware_directory)
: SysFSDirectory("bios", firmware_directory)
{
auto entry_32bit = find_dmi_entry32bit_point();
if (entry_32bit.has_value()) {
m_dmi_entry_point = entry_32bit.value();
}
auto entry_64bit = find_dmi_entry64bit_point();
if (entry_64bit.has_value()) {
m_dmi_entry_point = entry_64bit.value();
m_using_64bit_dmi_entry_point = true;
}
if (m_dmi_entry_point.is_null())
return;
initialize_dmi_exposer();
}
UNMAP_AFTER_INIT Optional<PhysicalAddress> BIOSSysFSDirectory::find_dmi_entry64bit_point()
{
return map_bios().find_chunk_starting_with("_SM3_", 16);
}
UNMAP_AFTER_INIT Optional<PhysicalAddress> BIOSSysFSDirectory::find_dmi_entry32bit_point()
{
return map_bios().find_chunk_starting_with("_SM_", 16);
}
Memory::MappedROM map_bios()
{
Memory::MappedROM mapping;
mapping.size = 128 * KiB;
mapping.paddr = PhysicalAddress(0xe0000);
mapping.region = MM.allocate_kernel_region(mapping.paddr, Memory::page_round_up(mapping.size), {}, Memory::Region::Access::Read).release_value();
return mapping;
}
Memory::MappedROM map_ebda()
{
auto ebda_segment_ptr = Memory::map_typed<u16>(PhysicalAddress(0x40e));
auto ebda_length_ptr_b0 = Memory::map_typed<u8>(PhysicalAddress(0x413));
auto ebda_length_ptr_b1 = Memory::map_typed<u8>(PhysicalAddress(0x414));
PhysicalAddress ebda_paddr(*ebda_segment_ptr << 4);
size_t ebda_size = (*ebda_length_ptr_b1 << 8) | *ebda_length_ptr_b0;
Memory::MappedROM mapping;
mapping.region = MM.allocate_kernel_region(ebda_paddr.page_base(), Memory::page_round_up(ebda_size), {}, Memory::Region::Access::Read).release_value();
mapping.offset = ebda_paddr.offset_in_page();
mapping.size = ebda_size;
mapping.paddr = ebda_paddr;
return mapping;
}
}