Added framebuffer.

Output is now to a framebuffer instead of serial console.

8 files changed, 109 insertions, 21 deletions

diff --git a/kernel/SConscript b/kernel/SConscript
index 4d91b9a..df6f10b 100644
--- a/kernel/SConscript
+++ b/kernel/SConscript
@@ -3,6 +3,7 @@ Import('env')
 kernel = env.Standalone('kernel', [
 	'kernel.ld',
 	'entry.c',
+	'framebuffer.c',
 	'gdt.c',
 	'idt.c',
 	'irq.c',
diff --git a/kernel/framebuffer.c b/kernel/framebuffer.c
new file mode 100644
index 0000000..220d556
--- /dev/null
+++ b/kernel/framebuffer.c
@@ -0,0 +1,74 @@
+#include "framebuffer.h"
+#include "kernel.h"
+#include "portio.h"
+
+uint16_t framebuffer_color = 0x0700;
+uint8_t framebuffer_x;
+uint8_t framebuffer_y;
+
+void framebuffer_init() {
+	union {uint8_t b[2]; uint16_t w;} pos;
+	
+	outb(0x3d4, 0x0f);
+	inb(0x3d5, pos.b[0]);
+	
+	outb(0x3d4, 0x0e);
+	inb(0x3d5, pos.b[1]);
+	
+	framebuffer_x = pos.w % 80;
+	framebuffer_y = pos.w / 80;
+}
+
+void framebuffer_putchar(char c) {
+	switch(c) {
+		case '\f':
+			framebuffer_clear();
+			break;
+		case '\r':
+			framebuffer_x = 0;
+			break;
+		case '\n':
+			framebuffer_x = 80;
+			break;
+		default:
+			framebuffer[framebuffer_y][framebuffer_x++] = framebuffer_color | c;
+	}
+	if(framebuffer_x == 80) {
+		framebuffer_x = 0;
+		if(framebuffer_y < 24) {
+			framebuffer_y++;
+		} else {
+			framebuffer_scroll();
+		}
+	}
+}
+
+void framebuffer_clear() {
+	for(int y = 0; y < 25; y++) {
+		for(int x = 0; x < 80; x++) {
+			framebuffer[y][x] = framebuffer_color;
+		}
+	}
+	framebuffer_x = framebuffer_y = 0;
+}
+
+void framebuffer_scroll() {
+	for(int y = 0; y < 24; y++) {
+		for(int x = 0; x < 80; x++) {
+			framebuffer[y][x] = framebuffer[y + 1][x];
+		}
+	}
+	for(int x = 0; x < 80; x++) {
+		framebuffer[24][x] = framebuffer_color;
+	}
+}
+
+void framebuffer_move_cursor() {
+	uint16_t pos = framebuffer_y * 80 + framebuffer_x;
+	
+	outb(0x3d4, 0x0f);
+	outb(0x3d5, pos & 0xff);
+	
+	outb(0x3d4, 0x0e);
+	outb(0x3d5, pos >> 8);
+}
diff --git a/kernel/framebuffer.h b/kernel/framebuffer.h
new file mode 100644
index 0000000..c57a187
--- /dev/null
+++ b/kernel/framebuffer.h
@@ -0,0 +1,10 @@
+#ifndef FRAMEBUFFER_H
+#define FRAMEBUFFER_H
+
+void framebuffer_init();
+void framebuffer_putchar(char c);
+void framebuffer_clear();
+void framebuffer_scroll();
+void framebuffer_move_cursor();
+
+#endif
diff --git a/kernel/kernel.h b/kernel/kernel.h
index ac313b1..3770c59 100755
--- a/kernel/kernel.h
+++ b/kernel/kernel.h
@@ -23,4 +23,6 @@ extern uint32_t entry_map_p1[2][1024];
 extern volatile uint32_t map_p2[1024];
 extern volatile union {uint32_t l[1024]; uint32_t b[1024][1024];} map_p1;
 
+extern uint16_t framebuffer[25][80];
+
 #endif
diff --git a/kernel/kernel.ld b/kernel/kernel.ld
index 3054aec..616d0a1 100755
--- a/kernel/kernel.ld
+++ b/kernel/kernel.ld
@@ -59,8 +59,9 @@ SECTIONS {
 	multiboot_info = .; . += 0x1000;
 	
 	. = 0x100000000;
-	stack_top = .; . -= 0x400000;
-	map_p2 = .; . -= 0x400000;
-	map_p1 = .;
+	stack_top = .; . -= 0x800000;
+	map_p1 = .; . += 0x400000;
+	map_p2 = .; . += 0x1000;
+	framebuffer = .; . += 0x1000;
 	
 }
diff --git a/kernel/main.c b/kernel/main.c
index d6de534..e5695b6 100644
--- a/kernel/main.c
+++ b/kernel/main.c
@@ -1,4 +1,5 @@
 #include "kernel.h"
+#include "framebuffer.h"
 #include "printf.h"
 #include "palloc.h"
 #include "paging.h"
@@ -6,15 +7,17 @@
 #include "idt.h"
 #include "irq.h"
 
+#include "portio.h"
+
 void main() {
+	paging_reinit();
+	
+	framebuffer_init();
 	printf("main()\n");
 	
 	palloc_init();
 	printf("Page allocator initiated.\n");
 	
-	paging_reinit();
-	printf("Paging reinitialized.\n");
-	
 	gdt_init();
 	printf("GDT set.\n");
 	
diff --git a/kernel/paging.c b/kernel/paging.c
index ca09936..88da0ab 100755
--- a/kernel/paging.c
+++ b/kernel/paging.c
@@ -5,6 +5,7 @@
 
 void paging_reinit() {
 	map_p1.l[(uint32_t)&map_p2 >> 12] = (uint32_t)&entry_map_p2 | P1_P | P1_W | P1_G;
+	map_p1.l[(uint32_t)&framebuffer >> 12] = 0xb8000 | P1_P | P1_W | P1_G;
 	
 	invlpg(&map_p2);
 	
diff --git a/kernel/printf.c b/kernel/printf.c
index 0b51f8d..61237aa 100644
--- a/kernel/printf.c
+++ b/kernel/printf.c
@@ -1,13 +1,6 @@
 #include "printf.h"
 #include "types.h"
-#include "portio.h"
-
-void putchar(char c) {
-	if(c == '\n') {
-		outb(0x3f8, '\r');
-	}
-	outb(0x3f8, c);
-}
+#include "framebuffer.h"
 
 int printf(const char* format, ...) {
 	int32_t* argp = (int32_t*)&format;
@@ -15,7 +8,7 @@ int printf(const char* format, ...) {
 	
 	while(*format) {
 		if(*format != '%') {
-			putchar(*format++);
+			framebuffer_putchar(*format++);
 			num++;
 			continue;
 		}
@@ -36,12 +29,12 @@ int printf(const char* format, ...) {
 		
 		switch(*format++) {
 			case '%':
-				putchar('%');
+				framebuffer_putchar('%');
 				num++;
 				break;
 			
 			case 'c':
-				putchar((char)*++argp);
+				framebuffer_putchar((char)*++argp);
 				num++;
 				break;
 			
@@ -49,7 +42,7 @@ int printf(const char* format, ...) {
 				;
 				char* str = (char*)*++argp;
 				while(*str) {
-					putchar(*str++);
+					framebuffer_putchar(*str++);
 					num++;
 				}
 				break;
@@ -63,7 +56,7 @@ int printf(const char* format, ...) {
 				uint32_t x = (uint32_t)*(++argp);
 				if(is_signed && (int32_t)x < 0) {
 					x = -x;
-					putchar('-');
+					framebuffer_putchar('-');
 					min_len--;
 				}
 				
@@ -79,17 +72,20 @@ int printf(const char* format, ...) {
 				} while(x);
 				
 				while(min_len > 0) {
-					putchar(zero_pad ? '0' : ' ');
+					framebuffer_putchar(zero_pad ? '0' : ' ');
 					num++;
 					min_len--;
 				}
 				
 				while(*bufp) {
-					putchar(*bufp++);
+					framebuffer_putchar(*bufp++);
 					num++;
 				}
 				break;
 		}
 	}
+	
+	framebuffer_move_cursor();
+	
 	return num;
 }