banan-os/kernel/kernel/PCI.cpp

114 lines
2.7 KiB
C++

#include <kernel/IO.h>
#include <kernel/PCI.h>
#define INVALID 0xFFFF
#define MULTI_FUNCTION 0x80
#define CONFIG_ADDRESS 0xCF8
#define CONFIG_DATA 0xCFC
namespace Kernel
{
static PCI* s_instance = nullptr;
void PCI::initialize()
{
ASSERT(s_instance == nullptr);
s_instance = new PCI();
ASSERT(s_instance);
s_instance->check_all_buses();
}
PCI& PCI::get()
{
ASSERT(s_instance);
return *s_instance;
}
static uint32_t read_config_dword(uint8_t bus, uint8_t dev, uint8_t func, uint8_t offset)
{
uint32_t config_addr = 0x80000000 | ((uint32_t)bus << 16) | ((uint32_t)dev << 11) | ((uint32_t)func << 8) | offset;
IO::outl(CONFIG_ADDRESS, config_addr);
return IO::inl(CONFIG_DATA);
}
static uint16_t get_vendor_id(uint8_t bus, uint8_t dev, uint8_t func)
{
uint32_t dword = read_config_dword(bus, dev, func, 0x00);
return dword & 0xFFFF;
}
static uint8_t get_header_type(uint8_t bus, uint8_t dev, uint8_t func)
{
uint32_t dword = read_config_dword(bus, dev, func, 0x0C);
return (dword >> 16) & 0xFF;
}
void PCI::check_function(uint8_t bus, uint8_t dev, uint8_t func)
{
MUST(m_devices.emplace_back(bus, dev, func));
auto& device = m_devices.back();
if (device.class_code() == 0x06 && device.subclass() == 0x04)
check_bus(device.read_byte(0x19));
}
void PCI::check_device(uint8_t bus, uint8_t dev)
{
if (get_vendor_id(bus, dev, 0) == INVALID)
return;
check_function(bus, dev, 0);
if (get_header_type(bus, dev, 0) & MULTI_FUNCTION)
for (uint8_t func = 1; func < 8; func++)
if (get_vendor_id(bus, dev, func) != INVALID)
check_function(bus, dev, func);
}
void PCI::check_bus(uint8_t bus)
{
for (uint8_t dev = 0; dev < 32; dev++)
check_device(bus, dev);
}
void PCI::check_all_buses()
{
if (get_header_type(0, 0, 0) & MULTI_FUNCTION)
{
for (int func = 0; func < 8 && get_vendor_id(0, 0, func) != INVALID; func++)
check_bus(func);
}
else
{
check_bus(0);
}
}
PCIDevice::PCIDevice(uint8_t bus, uint8_t dev, uint8_t func)
: m_bus(bus), m_dev(dev), m_func(func)
{
uint32_t type = read_word(0x0A);
m_class_code = (uint8_t)(type >> 8);
m_subclass = (uint8_t)(type);
}
uint32_t PCIDevice::read_dword(uint8_t offset) const
{
ASSERT((offset & 0x03) == 0);
return read_config_dword(m_bus, m_dev, m_func, offset);
}
uint16_t PCIDevice::read_word(uint8_t offset) const
{
ASSERT((offset & 0x01) == 0);
uint32_t dword = read_config_dword(m_bus, m_dev, m_func, offset & 0xFC);
return (uint16_t)(dword >> (8 * (offset & 0x03)));
}
uint8_t PCIDevice::read_byte(uint8_t offset) const
{
uint32_t dword = read_config_dword(m_bus, m_dev, m_func, offset & 0xFC);
return (uint8_t)(dword >> (8 * (offset & 0x03)));
}
}