seeseemelk/claude-os
1
0
Fork 0
Code Issues Pull Requests 2 Actions Packages Projects Releases 1 Wiki Activity
Files
e3d011da2fac0b8a67eaa646f90396bc51e2a61c
claude-os/src/kernel.c
AI e3d011da2f Fix UTM display: remove required framebuffer tag, add serial output, ls app 
Display fixes for UTM/Mac black screen issue:
- Remove MULTIBOOT_HEADER_TAG_FRAMEBUFFER from multiboot2 header (was required,
  requesting text mode depth=0 which confused GRUB on some platforms)
- Add COM1 serial port (0x3F8) output alongside debugcon for UTM serial capture
- Change VGA background from black to dark blue for diagnostics
- Add early canary write to 0xB8000 ('COS' in magenta) before subsystem init
- print_hex now outputs to both debugcon and COM1

New ls command and SYS_READDIR syscall:
- SYS_READDIR (10): reads directory entries via VFS
- VFS root listing: vfs_readdir handles '/' by iterating mount table
- apps/ls: lists CWD contents, appends '/' for directories
- apps/libc/syscalls.h: readdir() wrapper
2026-02-23 13:36:34 +00:00

284 lines
9.0 KiB
C
Raw Blame History

#include <multiboot2.h>
#include <stdint.h>
#include <stddef.h>
#include <string.h>
#include "gdt.h"
#include "idt.h"
#include "pic.h"
#include "port_io.h"
#include "pmm.h"
#include "paging.h"
#include "kmalloc.h"
#include "driver.h"
#include "vga.h"
#include "tss.h"
#include "syscall.h"
#include "process.h"
#include "cpio.h"
#include "vfs.h"
#include "initrd_fs.h"
#include "keyboard.h"
#include "framebuffer.h"
/* Global framebuffer info, parsed from multiboot2 tags. */
framebuffer_info_t fb_info;
/**
* Initialize COM1 serial port for debug output.
* Baud rate: 115200, 8N1.
*/
static void serial_init(void) {
outb(0x3F8 + 1, 0x00); /* Disable interrupts */
outb(0x3F8 + 3, 0x80); /* Enable DLAB */
outb(0x3F8 + 0, 0x01); /* Divisor low: 115200 baud */
outb(0x3F8 + 1, 0x00); /* Divisor high */
outb(0x3F8 + 3, 0x03); /* 8 bits, no parity, 1 stop */
outb(0x3F8 + 2, 0xC7); /* Enable FIFO */
outb(0x3F8 + 4, 0x03); /* RTS/DSR set */
}
static void serial_putc(char c) {
/* Wait for transmit buffer empty */
while (!(inb(0x3F8 + 5) & 0x20));
outb(0x3F8, c);
}
void offset_print(const char *str)
{
while (*str) {
outb(0xE9, *str); /* debugcon */
serial_putc(*str); /* COM1 serial */
str++;
}
}
void print_hex(uint32_t val)
{
const char *hex = "0123456789ABCDEF";
outb(0xE9, '0'); serial_putc('0');
outb(0xE9, 'x'); serial_putc('x');
for (int i = 28; i >= 0; i -= 4) {
char c = hex[(val >> i) & 0xF];
outb(0xE9, c);
serial_putc(c);
}
outb(0xE9, '\n'); serial_putc('\n');
}
void kernel_main(uint32_t magic, uint32_t addr) {
/* Initialize serial port first so all debug output goes to COM1 too */
serial_init();
/* Early canary: write directly to VGA text buffer at 0xB8000.
* If the display is in text mode, this will show a bright magenta 'C'
* in the top-left corner before any subsystem is initialized. */
{
volatile uint16_t *vga = (volatile uint16_t *)0xB8000;
vga[0] = (uint16_t)'C' | (0x5F << 8); /* magenta on magenta = visible block */
vga[1] = (uint16_t)'O' | (0x5F << 8);
vga[2] = (uint16_t)'S' | (0x5F << 8);
}
if (magic != MULTIBOOT2_BOOTLOADER_MAGIC) {
offset_print("Invalid magic number: ");
print_hex(magic);
return;
}
offset_print("Booting...\n");
init_gdt();
offset_print("GDT initialized\n");
init_idt();
offset_print("IDT initialized\n");
init_pic();
/* Unmask timer IRQ (IRQ0) explicitly */
pic_clear_mask(0);
offset_print("PIC initialized\n");
init_pmm(addr);
offset_print("PMM initialized\n");
/* Scan Multiboot2 tags for the initrd module and framebuffer info */
uint32_t initrd_start = 0, initrd_end = 0;
memset(&fb_info, 0, sizeof(fb_info));
{
struct multiboot_tag *tag;
for (tag = (struct multiboot_tag *)(addr + 8);
tag->type != MULTIBOOT_TAG_TYPE_END;
tag = (struct multiboot_tag *)((uint8_t *)tag + ((tag->size + 7) & ~7u))) {
if (tag->type == MULTIBOOT_TAG_TYPE_MODULE) {
struct multiboot_tag_module *mod = (struct multiboot_tag_module *)tag;
initrd_start = mod->mod_start;
initrd_end = mod->mod_end;
offset_print("Initrd module at ");
print_hex(initrd_start);
offset_print(" to ");
print_hex(initrd_end);
}
if (tag->type == MULTIBOOT_TAG_TYPE_FRAMEBUFFER) {
struct multiboot_tag_framebuffer *fbt =
(struct multiboot_tag_framebuffer *)tag;
fb_info.addr = (uint32_t)fbt->common.framebuffer_addr;
fb_info.pitch = fbt->common.framebuffer_pitch;
fb_info.width = fbt->common.framebuffer_width;
fb_info.height = fbt->common.framebuffer_height;
fb_info.bpp = fbt->common.framebuffer_bpp;
fb_info.type = fbt->common.framebuffer_type;
if (fb_info.type == FB_TYPE_RGB) {
fb_info.red_pos = fbt->framebuffer_red_field_position;
fb_info.red_size = fbt->framebuffer_red_mask_size;
fb_info.green_pos = fbt->framebuffer_green_field_position;
fb_info.green_size = fbt->framebuffer_green_mask_size;
fb_info.blue_pos = fbt->framebuffer_blue_field_position;
fb_info.blue_size = fbt->framebuffer_blue_mask_size;
}
offset_print("Framebuffer: type=");
print_hex(fb_info.type);
offset_print(" addr=");
print_hex(fb_info.addr);
offset_print(" ");
print_hex(fb_info.width);
offset_print(" x ");
print_hex(fb_info.height);
offset_print(" bpp=");
print_hex(fb_info.bpp);
}
}
}
init_paging();
offset_print("Paging initialized\n");
/* If GRUB provided a graphical framebuffer, identity-map it so
* the VGA driver can write pixels to it after paging is enabled. */
if (fb_info.addr != 0 && fb_info.type == FB_TYPE_RGB) {
uint32_t fb_size = fb_info.pitch * fb_info.height;
uint32_t fb_base = fb_info.addr & ~0xFFFu; /* page-align down */
uint32_t fb_end = (fb_info.addr + fb_size + 0xFFF) & ~0xFFFu;
offset_print(" Mapping framebuffer ");
print_hex(fb_base);
offset_print(" to ");
print_hex(fb_end);
for (uint32_t pa = fb_base; pa < fb_end; pa += 4096) {
paging_map_page(pa, pa, PAGE_PRESENT | PAGE_WRITE | PAGE_WRITETHROUGH);
}
}
/* Test paging: allocate a page and write to it */
void *test_page = paging_alloc_page();
if (test_page) {
offset_print("Allocated virtual page at: ");
print_hex((uint32_t)test_page);
*((volatile uint32_t *)test_page) = 0xDEADBEEF;
offset_print("Virtual page write/read OK\n");
paging_free_page(test_page);
} else {
offset_print("FAILED to allocate virtual page\n");
}
init_kmalloc();
offset_print("Memory allocator initialized\n");
/* Initialize CPIO ramdisk if module was loaded */
if (initrd_start != 0) {
cpio_init((const void *)initrd_start, initrd_end - initrd_start);
offset_print("CPIO ramdisk initialized\n");
} else {
offset_print("No initrd module found\n");
}
init_vfs();
offset_print("VFS initialized\n");
if (initrd_start != 0) {
init_initrd_fs();
offset_print("Initrd filesystem mounted\n");
/* Test VFS: read a file from the initrd */
int fd = vfs_open("/initrd/README", 0);
if (fd >= 0) {
char buf[64];
int32_t n = vfs_read(fd, buf, sizeof(buf) - 1);
if (n > 0) {
buf[n] = '\0';
offset_print("VFS read /initrd/README: ");
offset_print(buf);
}
vfs_close(fd);
}
}
init_tss();
offset_print("TSS initialized\n");
init_syscalls();
offset_print("Syscalls initialized\n");
keyboard_init();
offset_print("Keyboard initialized\n");
init_process();
offset_print("Process subsystem initialized\n");
init_drivers();
offset_print("Drivers initialized\n");
/* Show memory statistics and boot progress on VGA */
vga_show_mem_stats();
vga_puts("Boot complete.\n\n");
/* Test kmalloc/kfree */
uint32_t *test_alloc = (uint32_t *)kmalloc(64);
if (test_alloc) {
*test_alloc = 42;
offset_print("kmalloc(64) = ");
print_hex((uint32_t)test_alloc);
kfree(test_alloc);
offset_print("kfree OK\n");
} else {
offset_print("FAILED to kmalloc\n");
}
/* Load the initial program from the initrd and run it */
cpio_entry_t app_entry;
const char *init_app = "sh";
if (cpio_find(init_app, &app_entry) == 0) {
offset_print("Found ");
offset_print(init_app);
offset_print(" in initrd (");
print_hex(app_entry.datasize);
offset_print(" bytes)\n");
int32_t pid = process_create(init_app,
app_entry.data,
app_entry.datasize);
if (pid > 0) {
offset_print("Created init process, pid=");
print_hex((uint32_t)pid);
/* Enable interrupts before entering user mode */
asm volatile("sti");
offset_print("Interrupts enabled\n");
/* Enter user mode - does not return */
process_run_first();
} else {
offset_print("FAILED to create init process\n");
}
} else {
offset_print(init_app);
offset_print(" not found in initrd\n");
}
/* Enable interrupts */
asm volatile("sti");
offset_print("Interrupts enabled\n");
offset_print("Hello, world\n");
}
Reference in New Issue View Git Blame Copy Permalink