summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorBenji Dial <benji3.141@gmail.com>2020-05-16 14:10:08 -0400
committerBenji Dial <benji3.141@gmail.com>2020-05-16 14:10:08 -0400
commit31d8ae388a7ded576abd3e3d99c3d9193ea6d704 (patch)
tree9317308fbf0082924de414ef8416e76e927d79cd
parent806815e5f2612a45cdce6c47ace56146edfa7abf (diff)
downloadportland-os-31d8ae388a7ded576abd3e3d99c3d9193ea6d704.tar.gz
small stub with fat info
-rw-r--r--makefile3
-rw-r--r--src/boot.asm4
-rw-r--r--src/kernel/fat.h25
-rw-r--r--src/kernel/main.c9
-rw-r--r--src/kernel/vga.c77
-rw-r--r--src/kernel/vga.h9
6 files changed, 120 insertions, 7 deletions
diff --git a/makefile b/makefile
index efb5cf8..0de951a 100644
--- a/makefile
+++ b/makefile
@@ -1,3 +1,6 @@
+qemu: floppy
+ qemu-system-i386 out/floppy.img
+
floppy: kernel boot
mkdir -p obj out
/sbin/mkfs.fat -C -R 17 -n "PORTLAND OS" obj/shadow.img 1440
diff --git a/src/boot.asm b/src/boot.asm
index f9e3a30..fecf466 100644
--- a/src/boot.asm
+++ b/src/boot.asm
@@ -12,6 +12,10 @@ kernel_segment equ 0x3000
mov ss, ax
mov sp, 0x7ffc
+ mov ah, 0x01
+ mov ch, 0x3f
+ int 0x10
+
mov ax, kernel_segment
mov es, ax
mov ax, 0x0200 + kernel_sectors
diff --git a/src/kernel/fat.h b/src/kernel/fat.h
new file mode 100644
index 0000000..e7aa956
--- /dev/null
+++ b/src/kernel/fat.h
@@ -0,0 +1,25 @@
+#include <stdint.h>
+
+#define FAT_INFO ((struct fat_info *)0x7c03)
+
+struct fat_info {
+ uint8_t oem[8];
+ uint16_t bytes_per_sector;
+ uint8_t sectors_per_cluster;
+ uint16_t reserved_sectors;
+ uint8_t fats;
+ uint16_t root_entries;
+ uint16_t sectors;
+ uint8_t media_type;
+ uint16_t sectors_per_fat;
+ uint16_t sectors_per_track;
+ uint16_t heads;
+ uint32_t hidden_sectors;
+ uint32_t sectors_long;
+ uint8_t drive_number;
+ uint8_t reserved;
+ uint8_t ext_boot_marker;
+ uint32_t volume_id;
+ uint8_t label[11];
+ uint8_t fs_type[8];
+} __attribute__ ((packed)); \ No newline at end of file
diff --git a/src/kernel/main.c b/src/kernel/main.c
index 1a8b2f4..dbeb11b 100644
--- a/src/kernel/main.c
+++ b/src/kernel/main.c
@@ -1,7 +1,14 @@
#include <stdint.h>
#include "vga.h"
+#include "fat.h"
void main() {
+ vga_blank();
+ vga_printsz("In kernel-land\n\nDisk label: ");
+ vga_printsn(FAT_INFO->label, 11);
+ vga_printsz("\nDisk size: ");
+ vga_printu32((FAT_INFO->sectors * FAT_INFO->bytes_per_sector) >> 10);
+ vga_printsz("k\n\nHalting...");
while (1)
- vga_printsz("Hello! ");
+ asm ("hlt");
} \ No newline at end of file
diff --git a/src/kernel/vga.c b/src/kernel/vga.c
index d0170c0..8e438a8 100644
--- a/src/kernel/vga.c
+++ b/src/kernel/vga.c
@@ -1,14 +1,81 @@
#include <stdint.h>
+#include <stdbool.h>
+#define VGA_COLUMNS 80
+#define VGA_LINES 25
#define VGA_START (uint16_t *)0x000b8000
-#define VGA_END (VGA_START + 80 * 25)
+#define VGA_END (VGA_START + VGA_COLUMNS * VGA_LINES)
uint16_t *cursor = VGA_START;
uint16_t color = 0x1f00;
+void vga_scroll() {
+ cursor = VGA_START;
+}
+
+void vga_blank() {
+ uint32_t f = (color << 16) | color | 0x00200020;
+ uint32_t *p = (uint32_t *)VGA_START;
+ while (p < (uint32_t *)VGA_END)
+ *(p++) = f;
+ cursor = VGA_START;
+}
+
+void vga_printch(uint8_t ch) {
+ if (ch == '\n') {
+ if ((cursor = cursor - (cursor - VGA_START) % VGA_COLUMNS + VGA_COLUMNS) == VGA_END)
+ vga_scroll();
+ return;
+ }
+ *(cursor++) = color | ch;
+ if (cursor == VGA_END)
+ vga_scroll();
+}
+
void vga_printsz(uint8_t *sz) {
- while (*sz) {
- *(cursor++) = color | *(sz++);
- if (cursor == VGA_END)
- cursor = VGA_START;
+ while (*sz)
+ vga_printch(*(sz++));
+}
+
+void vga_printsn(uint8_t *sn, uint8_t n) {
+ while (n--)
+ vga_printch(*(sn++));
+}
+
+void vga_printu32(uint32_t n) {
+ bool zero = false;
+ for (uint32_t m = 1000000000; m; m /= 10) {
+ uint8_t d = (n / m) % 10;
+ if (zero)
+ vga_printch(d + '0');
+ else if (d) {
+ zero = true;
+ vga_printch(d + '0');
+ }
+ }
+}
+
+void vga_printu16(uint16_t n) {
+ bool zero = false;
+ for (uint16_t m = 10000; m; m /= 10) {
+ uint8_t d = (n / m) % 10;
+ if (zero)
+ vga_printch(d + '0');
+ else if (d) {
+ zero = true;
+ vga_printch(d + '0');
+ }
+ }
+}
+
+void vga_printu8(uint8_t n) {
+ bool zero = false;
+ for (uint8_t m = 100; m; m /= 10) {
+ uint8_t d = (n / m) % 10;
+ if (zero)
+ vga_printch(d + '0');
+ else if (d) {
+ zero = true;
+ vga_printch(d + '0');
+ }
}
} \ No newline at end of file
diff --git a/src/kernel/vga.h b/src/kernel/vga.h
index 47ac1fb..95c6335 100644
--- a/src/kernel/vga.h
+++ b/src/kernel/vga.h
@@ -1,3 +1,10 @@
#include <stdint.h>
-void vga_printsz(uint8_t *sz); \ No newline at end of file
+void vga_blank();
+void vga_scroll();
+void vga_printch(uint8_t ch);
+void vga_printsz(uint8_t *sz);
+void vga_printsn(uint8_t *sn, uint8_t n);
+void vga_printu32(uint32_t n);
+void vga_printu16(uint16_t n);
+void vga_printu8(uint8_t n); \ No newline at end of file