From 88982f25cd71538b618f90c2af8820d95a2cd115 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Felix=20Quei=C3=9Fner?= <git@mq32.de>
Date: Sun, 26 Jun 2016 15:48:43 +0200
Subject: [PATCH] Serial port driver.

---
 prototypes-rework/include/driver/serial.hpp | 37 ++++++++++++
 prototypes-rework/libserial/Makefile        | 12 ++++
 prototypes-rework/libserial/serial.cpp      | 66 +++++++++++++++++++++
 prototypes-rework/video/src/init.cpp        | 11 ----
 4 files changed, 115 insertions(+), 11 deletions(-)
 create mode 100644 prototypes-rework/include/driver/serial.hpp
 create mode 100644 prototypes-rework/libserial/Makefile
 create mode 100644 prototypes-rework/libserial/serial.cpp

diff --git a/prototypes-rework/include/driver/serial.hpp b/prototypes-rework/include/driver/serial.hpp
new file mode 100644
index 0000000..94b8595
--- /dev/null
+++ b/prototypes-rework/include/driver/serial.hpp
@@ -0,0 +1,37 @@
+#pragma once
+
+#include <stdint.h>
+
+#define SERIAL_COM1 0x3F8
+#define SERIAL_COM2 0x2F8
+#define SERIAL_COM3 0x3E8
+#define SERIAL_COM4 0x2E8
+
+enum class Partiy
+{
+	None = 0x0,
+	Even = 0x4,
+	Odd  = 0x6,
+	High = 0x5,
+	Low  = 0x7,
+};
+
+class SerialPort
+{
+private:
+	uint16_t mBase;
+public:
+	SerialPort(
+		uint32_t portBase, 
+		uint32_t baud = 9600, 
+		Partiy parity = Partiy::None,
+		uint8_t dataBits = 8);
+	
+	bool isTransmitEmpty() const;
+	
+	bool isReceiveEmpty() const;
+	
+	void write(uint8_t c);
+	
+	uint8_t read();
+};
\ No newline at end of file
diff --git a/prototypes-rework/libserial/Makefile b/prototypes-rework/libserial/Makefile
new file mode 100644
index 0000000..ff22aed
--- /dev/null
+++ b/prototypes-rework/libserial/Makefile
@@ -0,0 +1,12 @@
+##
+# Build serial port library.
+##
+
+include ../config.mk
+
+LIBRARY = libserial.a
+
+all: builddir $(LIBRARY)
+
+include ../common.mk
+include ../library.mk
\ No newline at end of file
diff --git a/prototypes-rework/libserial/serial.cpp b/prototypes-rework/libserial/serial.cpp
new file mode 100644
index 0000000..381c5fa
--- /dev/null
+++ b/prototypes-rework/libserial/serial.cpp
@@ -0,0 +1,66 @@
+#include <driver/serial.hpp>
+#include <io.hpp>
+
+// Code adapted from:
+// http://www.lowlevel.eu/wiki/Serielle_Schnittstelle
+
+#define IER 1
+#define IIR 2
+#define FCR 2
+#define LCR 3
+#define MCR 4
+#define LSR 5
+#define MSR 6
+
+SerialPort::SerialPort(uint32_t portBase, uint32_t baud, Partiy parity, uint8_t dataBits) : 
+	mBase(portBase)
+{
+	union {
+		uint8_t b[2];
+		uint16_t w;
+	} divisor;
+	divisor.w = 115200 / baud;
+
+	// Interrupt ausschalten
+	outb(this->mBase + IER, 0x00);
+
+	// DLAB-Bit setzen
+	outb(this->mBase + LCR, 0x80);
+
+	// Teiler (low) setzen
+	outb(this->mBase + 0, divisor.b[0]);
+
+	// Teiler (high) setzen
+	outb(this->mBase + 1, divisor.b[1]);
+
+	int iparity = (int)parity;
+	
+	// Anzahl Bits, Parität, usw setzen (DLAB zurücksetzen)
+	outb(this->mBase + LCR, ((iparity&0x7)<<3)|((dataBits-5)&0x3));
+
+	// Initialisierung abschließen
+	outb(this->mBase + FCR, 0xC7);
+	outb(this->mBase + MCR, 0x0B);
+}
+
+bool SerialPort::isTransmitEmpty() const
+{
+	return inb(this->mBase + LSR) & 0x20;
+}
+
+bool SerialPort::isReceiveEmpty() const
+{
+	return (inb(this->mBase + LSR) & 1) == 0;
+}
+
+void SerialPort::write(uint8_t c)
+{
+	while (this->isTransmitEmpty() == false);
+	outb(this->mBase, c);
+}
+
+uint8_t SerialPort::read()
+{
+	while (this->isReceiveEmpty());
+	return inb(this->mBase);
+}
diff --git a/prototypes-rework/video/src/init.cpp b/prototypes-rework/video/src/init.cpp
index 8714602..3c890a7 100644
--- a/prototypes-rework/video/src/init.cpp
+++ b/prototypes-rework/video/src/init.cpp
@@ -5,17 +5,6 @@
 
 #include <driver/video.hpp>
 
-// Prüft, ob man bereits schreiben kann
-static uint8_t is_transmit_empty(uint16_t base) {
-	return inb(base+5) & 0x20;
-}
- 
- // Byte senden
-static void write_com(uint16_t base, uint8_t chr) {
-	while (is_transmit_empty(base)==0);
-	outb(base,chr);
-}
-
 extern "C" void init(multiboot::Structure const & data)
 {
 	write_com(0x3F8, 'H');