--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/source/uart.c	Sun Oct 22 18:25:39 2017 +0900
@@ -0,0 +1,135 @@
+/*****************************************************************
+*       uart.c
+*       by Zhiyi Huang, hzy@cs.otago.ac.nz
+*       University of Otago
+*
+********************************************************************/
+
+
+
+#include "types.h"
+#include "defs.h"
+#include "memlayout.h"
+#include "traps.h"
+#include "arm.h"
+
+#define GPFSEL0			0xFE200000
+#define GPFSEL1			0xFE200004
+#define GPFSEL2			0xFE200008
+#define GPFSEL3			0xFE20000C
+#define	GPFSEL4			0xFE200010
+#define	GPFSEL5			0xFE200014
+#define GPSET0  		0xFE20001C
+#define GPSET1			0xFE200020
+#define GPCLR0  		0xFE200028
+#define GPCLR1			0xFE20002C
+#define GPPUD       		0xFE200094
+#define GPPUDCLK0   		0xFE200098
+#define GPPUDCLK1		0xFE20009C
+
+#define AUX_IRQ			0xFE215000
+#define AUX_ENABLES     	0xFE215004
+#define AUX_MU_IO_REG   	0xFE215040
+#define AUX_MU_IER_REG  	0xFE215044
+#define AUX_MU_IIR_REG  	0xFE215048
+#define AUX_MU_LCR_REG  	0xFE21504C
+#define AUX_MU_MCR_REG  	0xFE215050
+#define AUX_MU_LSR_REG  	0xFE215054
+#define AUX_MU_MSR_REG  	0xFE215058
+#define AUX_MU_SCRATCH  	0xFE21505C
+#define AUX_MU_CNTL_REG 	0xFE215060
+#define AUX_MU_STAT_REG 	0xFE215064
+#define AUX_MU_BAUD_REG 	0xFE215068
+
+void
+setgpioval(uint func, uint val)
+{
+	uint sel, ssel, rsel;
+
+	if(func > 53) return;
+	sel = func >> 5;
+	ssel = GPSET0 + (sel << 2);
+	rsel = GPCLR0 + (sel << 2);
+	sel = func & 0x1f;
+	if(val == 0) outw(rsel, 1<<sel);
+	else outw(ssel, 1<<sel);
+}
+
+
+void
+setgpiofunc(uint func, uint alt)
+{
+	uint sel, data, shift;
+
+	if(func > 53) return;
+	sel = 0;
+	while (func > 10) {
+	    func = func - 10;
+	    sel++;
+	}
+	sel = (sel << 2) + GPFSEL0;
+	data = inw(sel);
+	shift = func + (func << 1);
+	data &= ~(7 << shift);
+	data |= alt << shift;
+	outw(sel, data);
+}
+
+
+void 
+uartputc(uint c)
+{
+	if(c=='\n') {
+		while(1) if(inw(AUX_MU_LSR_REG) & 0x20) break;
+		outw(AUX_MU_IO_REG, 0x0d); // add CR before LF
+	}
+	while(1) if(inw(AUX_MU_LSR_REG) & 0x20) break;
+	outw(AUX_MU_IO_REG, c);
+}
+
+static int
+uartgetc(void)
+{
+	if(inw(AUX_MU_LSR_REG)&0x1) return inw(AUX_MU_IO_REG);
+	else return -1;
+}
+
+void 
+enableirqminiuart(void)
+{
+        intctrlregs *ip;
+
+        ip = (intctrlregs *)INT_REGS_BASE;
+        ip->gpuenable[0] |= (1 << 29);   // enable the miniuart through Aux
+}
+
+
+void
+miniuartintr(void)
+{
+  consoleintr(uartgetc);
+}
+
+void 
+uartinit(void)
+{
+	outw(AUX_ENABLES, 1);
+	outw(AUX_MU_CNTL_REG, 0);
+	outw(AUX_MU_LCR_REG, 0x3);
+	outw(AUX_MU_MCR_REG, 0);
+	outw(AUX_MU_IER_REG, 0x1);
+	outw(AUX_MU_IIR_REG, 0xC7);
+	outw(AUX_MU_BAUD_REG, 270); // (250,000,000/(115200*8))-1 = 270
+
+	setgpiofunc(14, 2); // gpio 14, alt 5
+	setgpiofunc(15, 2); // gpio 15, alt 5
+
+	outw(GPPUD, 0);
+	delay(10);
+	outw(GPPUDCLK0, (1 << 14) | (1 << 15) );
+	delay(10);
+	outw(GPPUDCLK0, 0);
+
+	outw(AUX_MU_CNTL_REG, 3);
+	enableirqminiuart();
+}