Kernel: Rework whole Terminal structure

Serial monitors can now be used as a output. This requires editing
init code for the stdio opening. Serial input is not supported, so qemu
still needs graphical window for ps/2 keyboard.

kernel/kernel/Terminal/Serial.cpp

@@ -0,0 +1,180 @@
+#include <BAN/Array.h>
+#include <kernel/FS/DevFS/FileSystem.h>
+#include <kernel/IO.h>
+#include <kernel/Terminal/Serial.h>
+
+#include <ctype.h>
+#include <sys/sysmacros.h>
+
+namespace Kernel
+{
+
+	static constexpr uint16_t s_serial_ports[] = { 0x3F8, 0x2F8, 0x3E8, 0x2E8, 0x5F8, 0x4F8, 0x5E8, 0x4E8 };
+	static BAN::Array<Serial, sizeof(s_serial_ports) / sizeof(*s_serial_ports)> s_serial_drivers;
+	static bool s_has_devices { false };
+
+
+	static dev_t next_rdev()
+	{
+		static dev_t major = DevFileSystem::get().get_next_dev();
+		static dev_t minor = 0;
+		return makedev(major, minor++);
+	}
+
+	void Serial::initialize()
+	{
+		int count = 0;
+		for (size_t i = 0; i < s_serial_drivers.size(); i++)
+		{
+			if (port_has_device(s_serial_ports[i]))
+			{
+				auto& driver = s_serial_drivers[i];
+				driver.m_port = s_serial_ports[i];
+				if (!driver.initialize_size())
+					continue;
+				count++;
+			}
+		}
+		s_has_devices = !!count;
+
+		for (auto& driver : s_serial_drivers)
+			dprintln("{}x{} serial device at 0x{H}", driver.width(), driver.height(), driver.port());
+	}
+
+	void Serial::initialize_devices()
+	{
+		for (auto& serial : s_serial_drivers)
+			if (serial.is_valid())
+				MUST(SerialTTY::create(serial));
+	}
+
+	bool Serial::port_has_device(uint16_t port)
+	{
+		IO::outb(port + 1, 0x00);	// Disable all interrupts
+		IO::outb(port + 3, 0x80);	// Enable DLAB (set baud rate divisor)
+		IO::outb(port + 0, 0x03);	// Set divisor to 3 (lo byte) 38400 baud
+		IO::outb(port + 1, 0x00);	//                  (hi byte)
+		IO::outb(port + 3, 0x03);	// 8 bits, no parity, one stop bit
+		IO::outb(port + 2, 0xC7);	// Enable FIFO, clear them, with 14-byte threshold
+		IO::outb(port + 4, 0x0B);	// IRQs enabled, RTS/DSR set
+		IO::outb(port + 4, 0x1E);	// Set in loopback mode, test the serial chip
+		IO::outb(port + 0, 0xAE);	// Test serial chip (send byte 0xAE and check if serial returns same byte)
+
+		// Check if serial is faulty (i.e: not same byte as sent)
+		if(IO::inb(port + 0) != 0xAE)
+			return false;
+
+		// If serial is not faulty set it in normal operation mode
+		// (not-loopback with IRQs enabled and OUT#1 and OUT#2 bits enabled)
+		IO::outb(port + 4, 0x0F);
+
+		return true;
+	}
+
+	bool Serial::initialize_size()
+	{
+		const char* query = "\e[999;999H\e[6n\e[H\e[J";
+
+		const char* ptr = query;
+		while (*ptr)
+			putchar(*ptr++);
+		
+		if (getchar() != '\033')
+			return false;
+		if (getchar() != '[')
+			return false;
+
+		auto read_number =
+			[&](char end)
+			{
+				uint32_t number = 0;
+				while (true)
+				{
+					char c = getchar();
+					if (c == end)
+						break;
+					if (!isdigit(c))
+						return UINT32_MAX;
+					number = (number * 10) + (c - '0');
+				}
+				return number;
+			};
+
+		m_height = read_number(';');
+		if (m_height == UINT32_MAX)
+		{
+			m_port = 0;
+			return false;
+		}
+
+		m_width = read_number('R');
+		if (m_width == UINT32_MAX)
+		{
+			m_port = 0;
+			return false;
+		}
+
+		return true;
+	}
+
+	bool Serial::has_devices()
+	{
+		return s_has_devices;
+	}
+ 
+	void Serial::putchar(char c)
+	{
+		while (!(IO::inb(m_port + 5) & 0x20))
+			continue;
+		IO::outb(m_port, c);
+	}
+
+	char Serial::getchar()
+	{
+		while (!(IO::inb(m_port + 5) & 0x01))
+			continue;
+		return IO::inb(m_port);
+	}
+
+	void Serial::putchar_any(char c)
+	{
+		for (auto& device : s_serial_drivers)
+			if (device.is_valid())
+				device.putchar(c);
+	}
+
+	SerialTTY::SerialTTY(Serial serial)
+		: TTY(0660, 0, 0)
+		, m_serial(serial)
+		, m_rdev(next_rdev())
+	{}
+
+	BAN::ErrorOr<BAN::RefPtr<SerialTTY>> SerialTTY::create(Serial serial)
+	{
+		auto* tty = new SerialTTY(serial);
+		ASSERT(tty);
+
+		ASSERT(minor(tty->rdev()) < 10);
+		char name[] = { 't', 't', 'y', 'S', (char)('0' + minor(tty->rdev())), '\0' };
+		
+		auto ref_ptr = BAN::RefPtr<SerialTTY>::adopt(tty);
+		DevFileSystem::get().add_device(name, ref_ptr);
+		return ref_ptr;
+	}
+	
+	uint32_t SerialTTY::width() const
+	{
+		return m_serial.width();
+	}
+
+	uint32_t SerialTTY::height() const
+	{
+		return m_serial.height();
+	}
+	
+	void SerialTTY::putchar(uint8_t ch)
+	{
+		m_serial.putchar(ch);
+	}
+
+}