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Kernel: Allow switching to IOAPIC mode even without enabling SMP

This small change allows to use the IOAPIC by default without to enable
SMP mode, which emulates Uni-Processor setup with IOAPIC instead of
using the PIC.

This opens the opportunity to utilize other types of interrupts like MSI
and MSI-X interrupts.
This commit is contained in:
Liav A 2021-11-28 17:38:10 +02:00 committed by Andreas Kling
parent f57900a41b
commit ac7953f945
5 changed files with 41 additions and 29 deletions

View file

@ -270,29 +270,32 @@ UNMAP_AFTER_INIT bool APIC::init_bsp()
return false;
}
auto madt = Memory::map_typed<ACPI::Structures::MADT>(madt_address.value());
size_t entry_index = 0;
size_t entries_length = madt->h.length - sizeof(ACPI::Structures::MADT);
auto* madt_entry = madt->entries;
while (entries_length > 0) {
size_t entry_length = madt_entry->length;
if (madt_entry->type == (u8)ACPI::Structures::MADTEntryType::LocalAPIC) {
auto* plapic_entry = (const ACPI::Structures::MADTEntries::ProcessorLocalAPIC*)madt_entry;
dbgln_if(APIC_DEBUG, "APIC: AP found @ MADT entry {}, processor ID: {}, xAPIC ID: {}, flags: {:#08x}", entry_index, plapic_entry->acpi_processor_id, plapic_entry->apic_id, plapic_entry->flags);
m_processor_cnt++;
if ((plapic_entry->flags & 0x1) != 0)
m_processor_enabled_cnt++;
} else if (madt_entry->type == (u8)ACPI::Structures::MADTEntryType::Local_x2APIC) {
// Only used for APID IDs >= 255
auto* plx2apic_entry = (const ACPI::Structures::MADTEntries::ProcessorLocalX2APIC*)madt_entry;
dbgln_if(APIC_DEBUG, "APIC: AP found @ MADT entry {}, processor ID: {}, x2APIC ID: {}, flags: {:#08x}", entry_index, plx2apic_entry->acpi_processor_id, plx2apic_entry->apic_id, plx2apic_entry->flags);
m_processor_cnt++;
if ((plx2apic_entry->flags & 0x1) != 0)
m_processor_enabled_cnt++;
if (kernel_command_line().is_smp_enabled()) {
auto madt = Memory::map_typed<ACPI::Structures::MADT>(madt_address.value());
size_t entry_index = 0;
size_t entries_length = madt->h.length - sizeof(ACPI::Structures::MADT);
auto* madt_entry = madt->entries;
while (entries_length > 0) {
size_t entry_length = madt_entry->length;
if (madt_entry->type == (u8)ACPI::Structures::MADTEntryType::LocalAPIC) {
auto* plapic_entry = (const ACPI::Structures::MADTEntries::ProcessorLocalAPIC*)madt_entry;
dbgln_if(APIC_DEBUG, "APIC: AP found @ MADT entry {}, processor ID: {}, xAPIC ID: {}, flags: {:#08x}", entry_index, plapic_entry->acpi_processor_id, plapic_entry->apic_id, plapic_entry->flags);
m_processor_cnt++;
if ((plapic_entry->flags & 0x1) != 0)
m_processor_enabled_cnt++;
} else if (madt_entry->type == (u8)ACPI::Structures::MADTEntryType::Local_x2APIC) {
// Only used for APID IDs >= 255
auto* plx2apic_entry = (const ACPI::Structures::MADTEntries::ProcessorLocalX2APIC*)madt_entry;
dbgln_if(APIC_DEBUG, "APIC: AP found @ MADT entry {}, processor ID: {}, x2APIC ID: {}, flags: {:#08x}", entry_index, plx2apic_entry->acpi_processor_id, plx2apic_entry->apic_id, plx2apic_entry->flags);
m_processor_cnt++;
if ((plx2apic_entry->flags & 0x1) != 0)
m_processor_enabled_cnt++;
}
madt_entry = (ACPI::Structures::MADTEntryHeader*)(VirtualAddress(madt_entry).offset(entry_length).get());
entries_length -= entry_length;
entry_index++;
}
madt_entry = (ACPI::Structures::MADTEntryHeader*)(VirtualAddress(madt_entry).offset(entry_length).get());
entries_length -= entry_length;
entry_index++;
dbgln("APIC processors found: {}, enabled: {}", m_processor_cnt, m_processor_enabled_cnt);
}
if (m_processor_enabled_cnt < 1)
@ -300,8 +303,6 @@ UNMAP_AFTER_INIT bool APIC::init_bsp()
if (m_processor_cnt < 1)
m_processor_cnt = 1;
dbgln("APIC processors found: {}, enabled: {}", m_processor_cnt, m_processor_enabled_cnt);
enable(0);
return true;
}