Start adding simple video console which uses framebuffer

Makefile

@@ -15,8 +15,9 @@ LD = $(TOOL_PREFIX)ld
 
 # Define the flags we'll need for our tools
 INCLUDES = -I include
-KCFLAGS = -Wall -Wextra -Werror -nostdlib -nostartfiles -ffreestanding -std=gnu99 $(INCLUDES)
-KLDFLAGS = -T link.ld
+KCFLAGS = -Wall -Wextra -Werror -nostdlib -nostartfiles -fno-builtin -std=gnu99 $(INCLUDES)
+KLDFLAGS = -T link.ld -L /usr/lib/gcc/arm-elf/4.7.0/
+EXTRA_LIBS = -lgcc
 
 KOBJS = 
 
@@ -30,7 +31,7 @@ all: aedrix-kernel
 
 aedrix-kernel: $(KOBJS)
 	$(if $(VERBOSE:1=),@echo '     LD $@')
-	$(if $(VERBOSE:1=),@)$(LD) $(KLDFLAGS) -o $@ $(KOBJS)
+	$(if $(VERBOSE:1=),@)$(LD) $(KLDFLAGS) -o $@ $(KOBJS) $(EXTRA_LIBS)
 
 %.o: %.c
 	$(if $(VERBOSE:1=),@echo '     CC $@')

include/console.h

@@ -0,0 +1,6 @@
+#ifndef CONSOLE_H
+#define CONSOLE_H
+
+void console_init(struct fb *f);
+
+#endif /* CONSOLE_H */

kernel/Makefile.inc

@@ -1,5 +1,6 @@
 KERNEL_PREFIX = kernel
 
+KOBJS += $(KERNEL_PREFIX)/console.o
 KOBJS += $(KERNEL_PREFIX)/font.o
 KOBJS += $(KERNEL_PREFIX)/framebuffer.o
 KOBJS += $(KERNEL_PREFIX)/print.o

kernel/console.c

@@ -0,0 +1,60 @@
+#include <font.h>
+#include <framebuffer.h>
+
+#define CONSOLE_BUFFER_SIZE 16384
+char console_buffer[CONSOLE_BUFFER_SIZE];
+char console_output_buffer[CONSOLE_BUFFER_SIZE];
+char *console_buffer_p = console_buffer;
+struct fb *console_framebuffer = 0;
+struct font *console_font = 0;
+unsigned int chars_per_line = 0, lines = 0;
+
+void console_char_to_fb(char c, unsigned int x, unsigned int y) {
+	unsigned int cx, cy, bit = 0;
+	char *font_char = &console_font->data[console_font->bytes_per_char * (c - console_font->ascii_offset)];
+
+	for (cy = 0; cy < console_font->height; cy++) {
+		for (cx = 0; cx < console_font->width; cx++) {
+			unsigned char on = font_char[bit / 8] & (1 << (bit % 8));
+			if (on)
+				fb_write_pixel(console_framebuffer, x + cx, y + cy, 0xff, 0xff, 0xff);
+			else
+				fb_write_pixel(console_framebuffer, x + cx, y + cy, 0x00, 0x00, 0x00);
+			bit++;
+		}
+	}
+}
+
+void console_refresh_fb() {
+	if (!console_framebuffer)
+		return;
+}
+
+void console_clear() {
+	int i;
+	for (i = 0; i < CONSOLE_BUFFER_SIZE; i++) {
+		console_buffer[i] = 0;
+	}
+}
+
+void console_init(struct fb *f) {
+	console_clear();
+	console_refresh_fb();
+	console_font = font_get();
+	console_framebuffer = f;
+	chars_per_line = console_framebuffer->width / console_font->width;
+	lines = console_framebuffer->height / console_font->height;
+
+	console_char_to_fb('A', 100, 100);
+	console_char_to_fb('E', 111, 100);
+	console_char_to_fb('D', 122, 100);
+	console_char_to_fb('R', 133, 100);
+	console_char_to_fb('I', 144, 100);
+	console_char_to_fb('X', 155, 100);
+}
+
+void console_putc(char c) {
+	*console_buffer_p = c;
+	if (++console_buffer_p > console_buffer + CONSOLE_BUFFER_SIZE)
+		console_buffer_p = console_buffer;
+}

kernel/start_kernel.c

@@ -3,25 +3,24 @@
 
 #include <devices/pl110.h>
 #include <framebuffer.h>
+#include <console.h>
 
 struct fb myfb;
 
-void video(void)
-{
-	unsigned int x, y;
-	pl110_init(&myfb, 16);
-	x = 0, y = 0;
-	for (y=0; y<480; y++)
-		for (x=0; x<640; x++)
-			fb_write_pixel(&myfb, x, y, 0xff, 0x00, 0x00);
+void video(void) {
+//	unsigned int x, y;
+	pl110_init(&myfb, 24);
+//	x = 0, y = 0;
+//	for (y=0; y<480; y++)
+//		for (x=0; x<640; x++)
+//			fb_write_pixel(&myfb, x, y, 0x3f, 0x0, 0x6f);
+	console_init(&myfb);
 }
  
-int main(void)
-{
+int main(void) {
 	print_init(&pl011_putc); //initialize the serial console
 
 	video();
 
-	print("hello, world!\n");
 	return 0;
 }