added seperate x86 UART routines for HW debugging (115200 baud, 8N1)

arch/x86/include/asm/io.h

@@ -100,11 +100,6 @@ inline static void outportl(unsigned short _port, unsigned int _data)
 	 asm volatile("outl %1, %0"::"dN"(_port), "a"(_data));
 }
 
-inline static void uart_putchar(unsigned char _data)
-{
-	outportb(UART_PORT, _data);
-}
-
 /**
  * read a byte from CMOS
  *  @param offset CMOS offset

arch/x86/include/asm/uart.h

@@ -0,0 +1,74 @@
+/* 
+ * Copyright 2010 Steffen Vogel, Chair for Operating Systems,
+ *                               RWTH Aachen University
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * This file is part of MetalSVM.
+ */
+
+/** 
+ * @author Steffen Vogel
+ * @file arch/x86/include/asm/uart.h
+ * @brief COM port related code
+ */
+
+#ifndef __ARCH_UART_H__
+#define __ARCH_UART_H__
+
+#include <metalsvm/stddef.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef CONFIG_UART
+
+/** @brief Initialize VGA output and clear the screen */
+void uart_init(void);
+
+/** @brief Send a single character to the uart
+ *
+ * @return The original input character casted to int 
+ */
+void uart_putchar(char c);
+
+/** @brief Receive a single character on the uart
+ *
+ * @return The original input character casted to int 
+ */
+char uart_getchar(void);
+
+/** @brief Simple string output on screen.
+ *
+ * If you want a new line you will have to "\\n".
+ *
+ * @return Length of output in bytes
+ */
+void uart_puts(const char *str);
+
+/** @brief Simple string output on screen.
+ *
+ * If you want a new line you will have to "\\n".
+ *
+ * @return Length of output in bytes
+ */
+int uart_gets(char *str, size_t len);
+
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

arch/x86/kernel/Makefile

@@ -1,4 +1,4 @@
-C_source := gdt.c kb.c timer.c irq.c isrs.c idt.c vga.c multiboot.c apic.c pci.c processor.c
+C_source := gdt.c kb.c timer.c irq.c isrs.c idt.c vga.c uart.c multiboot.c apic.c pci.c processor.c
 ASM_source := entry$(BIT).asm string$(BIT).asm
 MODULE := arch_x86_kernel
 

arch/x86/kernel/uart.c

@@ -0,0 +1,68 @@
+/* 
+ * Copyright 2011 Steffen Vogel, Chair for Operating Systems,
+ *                               RWTH Aachen University
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * This file is part of MetalSVM.
+ */
+
+#include <asm/uart.h>
+#include <asm/io.h>
+
+static inline int is_transmit_empty()
+{
+	return inportb(UART_PORT + 5) & 0x20;
+}
+
+static inline int received()
+{
+	return inportb(UART_PORT + 5) & 1;
+}
+
+void uart_init()
+{
+	outportb(UART_PORT + 1, 0x00);	// Disable all interrupts
+	outportb(UART_PORT + 3, 0x80);	// Enable DLAB (set baud rate divisor)
+	outportb(UART_PORT + 0, 0x0C);	// Set divisor to 12 (lo byte) 9600 baud
+	outportb(UART_PORT + 1, 0x00);	//                   (hi byte)
+	outportb(UART_PORT + 3, 0x03);	// 8 bits, no parity, one stop bit (8N1)
+	outportb(UART_PORT + 2, 0xC7);	// Enable FIFO, clear them, with 14-byte threshold
+	outportb(UART_PORT + 4, 0x0B);	// IRQs enabled, RTS/DSR set
+}
+
+char uart_getchar()
+{
+	while (!received());
+	return inportb(UART_PORT);
+}
+
+void uart_putchar(char chr)
+{
+	while (!is_transmit_empty());
+	outportb(UART_PORT, chr);
+}
+
+void uart_puts(const char* str)
+{
+	while (*str) uart_putchar(*(str++));
+}
+
+int uart_gets(char* str, size_t len)
+{
+	size_t ret = 0;
+	while (ret < len)
+		str[ret] = uart_getchar();
+
+	return ret;
+}

libkern/stdio.c

@@ -163,8 +163,12 @@ int kputchar(int c)
 		vga_putchar(c);
 #endif
 #ifdef CONFIG_UART
-	if (early_print & UART_EARLY_PRINT)
+	if (early_print & UART_EARLY_PRINT) {
+		if (c == '\n')
+			uart_putchar('\r');
+
 		uart_putchar(c);
+	}
 #endif
 
 	if (early_print != NO_EARLY_PRINT)
@@ -189,6 +193,9 @@ int kputs(const char *str)
 #endif
 #ifdef CONFIG_UART
 		if (early_print & UART_EARLY_PRINT)
+			if (str[i] == '\n')
+				uart_putchar('\r');
+
 			uart_putchar(str[i]);
 #endif
 	}