Luna/kernel/src/arch/PCI.cpp

125 lines
3.5 KiB
C++

#include "arch/PCI.h"
#include "Log.h"
struct ScanInfo
{
PCI::Callback callback;
PCI::Match match;
};
namespace PCI
{
BAR::BAR(u32 raw) : m_raw(raw)
{
}
Device::ID read_id(const Device::Address& address)
{
const u16 vendor = read16(address, Field::VendorID);
const u16 device = read16(address, Field::DeviceID);
return { vendor, device };
}
Device::Type read_type(const Device::Address& address)
{
const u8 klass = read8(address, Field::Class);
const u8 subclass = read8(address, Field::Subclass);
const u8 prog_if = read8(address, Field::ProgIF);
return { klass, subclass, prog_if };
}
constexpr u8 PCI_BRIDGE_CLASS = 0x06;
constexpr u8 PCI_TO_PCI_BRIDGE_SUBCLASS = 0x04;
static bool is_pci_to_pci_bridge(const Device::Address& address)
{
return read8(address, Field::Class) == PCI_BRIDGE_CLASS &&
read8(address, Field::Subclass) == PCI_TO_PCI_BRIDGE_SUBCLASS;
}
static bool matches(const Device::Type& type, const Match& match)
{
if (match.klass != -1 && type.klass != match.klass) return false;
if (match.subclass != -1 && type.subclass != match.subclass) return false;
if (match.prog_if != -1 && type.prog_if != match.prog_if) return false;
return true;
}
void scan_bus(u32, ScanInfo);
void scan_function(const Device::Address& address, ScanInfo info)
{
const Device::ID id = read_id(address);
const Device::Type type = read_type(address);
if (matches(type, info.match)) { info.callback({ id, type, address }); }
if (is_pci_to_pci_bridge(address))
{
kdbgln("PCI-to-PCI bridge detected, performing another bus scan");
scan_bus(read8(address, Field::SecondaryBus), info);
}
}
void scan_slot(u32 bus, u32 slot, ScanInfo info)
{
Device::Address address { bus, slot, 0 };
// No device on this slot!
if (read16(address, Field::VendorID) == PCI::INVALID_ID) return;
scan_function(address, info);
const u8 header_type = read8(address, Field::HeaderType);
// Multiple-function PCI device
if ((header_type & 0x80) == 0x80)
{
for (u32 function = 1; function < 8; function++)
{
address.function = function;
if (read16(address, Field::VendorID) == PCI::INVALID_ID) continue;
scan_function(address, info);
}
}
}
void scan_bus(u32 bus, ScanInfo info)
{
for (u32 slot = 0; slot < 32; slot++) { scan_slot(bus, slot, info); }
}
void scan(Callback callback, Match match)
{
const u8 header_type = read8({ 0, 0, 0 }, Field::HeaderType);
// Single-function PCI bus
if ((header_type & 0x80) == 0)
{
kdbgln("PCI bus is single-function");
scan_bus(0, { callback, match });
}
else
{
kdbgln("PCI bus is multiple-function");
for (u32 function = 0; function < 8; function++)
{
if (read16({ 0, 0, function }, Field::VendorID) != PCI::INVALID_ID)
{
kdbgln("PCI bus has function %u", function);
scan_bus(function, { callback, match });
}
}
}
}
BAR Device::getBAR(u8 index) const
{
check(index < 6);
u32 raw = read32(address, 0x10 + (index * 4));
return { raw };
}
}