ladybird/Kernel/Devices/PCISerialDevice.cpp
Andreas Kling ac7ce12123 Kernel: Remove the kmalloc_eternal heap :^)
This was a premature optimization from the early days of SerenityOS.
The eternal heap was a simple bump pointer allocator over a static
byte array. My original idea was to avoid heap fragmentation and improve
data locality, but both ideas were rooted in cargo culting, not data.

We would reserve 4 MiB at boot and only ended up using ~256 KiB, wasting
the rest.

This patch replaces all kmalloc_eternal() usage by regular kmalloc().
2021-12-28 21:02:38 +01:00

54 lines
1.8 KiB
C++

/*
* Copyright (c) 2021, Idan Horowitz <idan.horowitz@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <Kernel/Bus/PCI/API.h>
#include <Kernel/Devices/PCISerialDevice.h>
#include <Kernel/Sections.h>
namespace Kernel {
static SerialDevice* s_the = nullptr;
UNMAP_AFTER_INIT void PCISerialDevice::detect()
{
size_t current_device_minor = 68;
PCI::enumerate([&](PCI::DeviceIdentifier const& device_identifier) {
for (auto& board_definition : board_definitions) {
if (board_definition.device_id != device_identifier.hardware_id())
continue;
auto bar_base = PCI::get_BAR(device_identifier.address(), board_definition.pci_bar) & ~1;
auto port_base = IOAddress(bar_base + board_definition.first_offset);
for (size_t i = 0; i < board_definition.port_count; i++) {
auto serial_device = new SerialDevice(port_base.offset(board_definition.port_size * i), current_device_minor++);
if (board_definition.baud_rate != SerialDevice::Baud::Baud38400) // non-default baud
serial_device->set_baud(board_definition.baud_rate);
// If this is the first port of the first pci serial device, store it as the debug PCI serial port (TODO: Make this configurable somehow?)
if (!is_available())
s_the = serial_device;
// NOTE: We intentionally leak the reference to serial_device here.
}
dmesgln("PCISerialDevice: Found {} @ {}", board_definition.name, device_identifier.address());
return;
}
});
}
SerialDevice& PCISerialDevice::the()
{
VERIFY(s_the);
return *s_the;
}
bool PCISerialDevice::is_available()
{
return s_the;
}
}