Moving components modules to a more proper directory

components/serial/serial.c

@@ -0,0 +1,89 @@
+#include "serial.h"
+
+/*
+ * SERIAL_LINE_COMMAND_PORT configuration
+ * Bit:     | 7 | 6 | 5 4 3 | 2 | 1 0 |
+ * Content: | d | b | prty  | s | dl  |
+ * d = enable/disable DLAB
+ * b = enable/disable break control
+ * prty = # of parity bits to use
+ * s = # no of stop bits [0 is 1] and [1 is 1.5 or 2]
+ * dl = length of data
+ *
+ */
+
+void serial_set_baud_rate(const u16 com_port, const u16 divisor) {
+	// Activate line - ready to send higher 8 bits of data
+	// send the higher 8 bits first
+	// send the lower 8 bits next
+
+	serialport_write_byte(SERIAL_LINE_COMMAND_PORT(com_port), 
+			SERIAL_LINE_ENABLE);
+
+	serialport_write_byte(SERIAL_DATA_PORT(com_port), 
+			(divisor>>8) & 0x00ff);
+
+	serialport_write_byte(SERIAL_DATA_PORT(com_port), 
+			divisor & 0x00ff);
+}
+
+// Payload described above
+void serial_configure_line(const u16 line, const u8 payload) {
+	serialport_write_byte(SERIAL_LINE_COMMAND_PORT(line), payload);
+}
+
+
+u8 serial_fifo_empty(const u16 com_port) {
+	// we get back 0x20 if it is empty
+	return serial_read_byte(SERIAL_LINE_STATUS_PORT(com_port)) & 
+		SERIAL_FIFO_EMPTY_CODE;
+}
+
+u64 serial_write(const char* buffer, const u64 size) {
+	/*
+	 * Writes a given buffer to the com1 serial port for debugging in bochs
+	 */
+	serialport_write_byte(SERIAL_DATA_PORT_INT_EN(SERIAL_COM1_BASE), 
+			0x00);
+
+	serialport_write_byte(SERIAL_LINE_COMMAND_PORT(SERIAL_COM1_BASE), 
+			SERIAL_LINE_ENABLE);
+
+	// quarter speed hopefully the fifo quue wont fill this way
+	serialport_write_byte(SERIAL_COM1_BASE, 
+			0x01);
+
+	serialport_write_byte(SERIAL_DATA_PORT_INT_EN(SERIAL_COM1_BASE),
+			0x00);
+
+	serialport_write_byte(SERIAL_LINE_COMMAND_PORT(SERIAL_COM1_BASE), 
+			SERIAL_DEFAULT_LINE_CFG);
+
+	serialport_write_byte(SERIAL_FIFO_COMMAND_PORT(SERIAL_COM1_BASE),
+			SERIAL_DEFAULT_BUFFER_CFG);
+
+	serialport_write_byte(SERIAL_MODEM_COMMAND_PORT(SERIAL_COM1_BASE),
+			0x0B);
+
+	u64 idx;
+	for(idx =0; idx < size; idx++) {
+		serialport_write_byte(SERIAL_COM1_BASE, buffer[idx]);
+	}
+	return idx;
+}
+
+
+void serial_pic_ack(u32 interrupt) {
+	// ignore things that are too small and too big
+	if(interrupt < PIC1_START_INT || interrupt > PIC2_END_INT) {
+		return;
+	}
+	// Send acknoldgement to the pic that we have handled the interrupt
+	// without this it literally just wait for the ack
+	if(interrupt < PIC2_START_INT) {
+		serialport_write_byte(PIC1_PORT, PIC_ACK);
+	}
+	else {
+		serialport_write_byte(PIC2_PORT, PIC_ACK);
+	}
+}

components/serial/serial.h

@@ -0,0 +1,43 @@
+#include "types.h"
+#include "ports.h"
+
+// Serial driver interface
+
+#define SERIAL_COM1_BASE 				0x03F8
+
+#define SERIAL_DATA_PORT(base) 			(base)
+#define SERIAL_DATA_PORT_INT_EN(base)	(base+1)
+#define SERIAL_FIFO_COMMAND_PORT(base) 	(base+2)
+#define SERIAL_LINE_COMMAND_PORT(base) 	(base+3)
+#define SERIAL_MODEM_COMMAND_PORT(base) (base+4)
+#define SERIAL_LINE_STATUS_PORT(base) 	(base+5)
+
+#define SERIAL_LINE_ENABLE 				0x80
+
+// Default configurations for serial ports/lines/buffers etc.
+// Rational can be found here: https://littleosbook.github.io/#configuring-the-buffers
+#define SERIAL_DEFAULT_LINE_CFG 0x03
+#define SERIAL_DEFAULT_BUFFER_CFG 0xc7
+#define SERIAL_DEFAULT_MODEM_CFG 0x03
+
+#define SERIAL_FIFO_EMPTY_CODE 0x20
+
+#define PIC1_PORT 0x20
+#define PIC2_PORT 0xA0
+
+#define PIC1_START_INT 0x20
+#define PIC1_END_INT 0x27
+#define PIC2_START_INT 0x28
+#define PIC2_END_INT 0x2F
+
+#define PIC_ACK 0x20
+
+void serial_set_baud_rate(const u16, const u16);
+
+void serial_configure_line(const u16, const u8); 
+
+u8 serial_fifo_empty(const u16);
+
+u64 serial_write(const char* buffer, const u64 size);
+
+void serial_pic_ack(u32 interrupt);