Files
kern/boot/stage3.c
T
2024-10-10 10:03:58 +02:00

84 lines
2.8 KiB
C

#include <memory/physical.h>
#include <memory/virtual.h>
#include <memory/addresses.h>
#include <screen/gfxmode.h>
#include <screen/text.h>
#include <error/bigerr.h>
#include <disk/disk.h>
#include <fs/impl.h>
#include <fs/fs.h>
#include <stdio.h>
__attribute__ ((section("entry")))
void main() {
// Physical memory manager setup
uint32_t smapEntryCount = *(uint32_t*)SMAP_ENTRY_COUNT;
smapEntry_t* smapEntries = (smapEntry_t*)SMAP_ENTRIES;
smapEntries += smapEntryCount - 1;
uint32_t totalMemory = smapEntries->baseAddress + smapEntries->length - 1;
setupPhysicalMemoryManager(MEMMAP_AREA, totalMemory);
smapEntries = (smapEntry_t*)SMAP_ENTRIES;
for (uint32_t i = 0; i < smapEntryCount; i++) {
if (smapEntries[i].type == 1) {
initMemoryRegion(smapEntries[i].baseAddress, smapEntries[i].length);
}
}
deinitMemoryRegion(0x1000, 0x11fff); // Reserve kernel memory (under 0x12000)
deinitMemoryRegion(MEMMAP_AREA, maxBlocks / BLOCKS_PER_BYTE);
// Load root dir, find kernel INode and parse it
superblock_t* sb = (superblock_t*)SUPERBLOCK_LOC;
sb->rootInodePtr = BOOT_FIRST_INODE_LOC + sizeof(inode_t);
inode_t* root = (inode_t*)sb->rootInodePtr;
loadFile(root, (void*)SCRATCH_BLOCK_LOC);
inode_t* inode;
if ((inode = getInode("kernel.bin", (dirEntry_t*)SCRATCH_BLOCK_LOC)) == NULL) {
// kernel.bin doesn't exist??? very bad -> error
bigError(0xDEAD);
} else { loadFile(inode, (void*)KERNEL_LOC); }
font_t* font = (font_t*)FONT_LOC;
if ((inode = getInode("term16n.fnt", (dirEntry_t*)SCRATCH_BLOCK_LOC)) != NULL) {
loadFile(inode, font);
} else if ((inode = getInode("testfont.fnt", (dirEntry_t*)SCRATCH_BLOCK_LOC)) != NULL) {
loadFile(inode, font);
} else {
// No font found, bad.
bigError(0xBeef);
}
// Virtual memory manager setup
if (setupVirtualMemoryManager() != 0) {
bigError(0xCafe);
}
// Identity map VBE framebuffer
uint32_t fbSize = (gfxMode->yRes * gfxMode->linearBytesPerScanline) / PAGE_SIZE;
if (fbSize % PAGE_SIZE > 0) { fbSize++; }
fbSize *= 2; // Double for hardware
for (uint32_t i = 0, fbStart = gfxMode->physicalBasePtr; i < fbSize; i++, fbStart += PAGE_SIZE) {
mapPage((void*)fbStart, (void*)fbStart);
}
deinitMemoryRegion(gfxMode->physicalBasePtr, fbSize * BLOCK_SIZE);
*(uint32_t*)PHYS_MEM_MAX_BLOCKS = maxBlocks;
*(uint32_t*)PHYS_MEM_USED_BLOCKS = usedBlocks;
for (uint32_t virt = KERNEL_LOC; virt < 0x400000; virt += PAGE_SIZE) {
unmapPage((void*)virt);
}
__asm__ volatile ("movl %cr3, %ecx; movl %ecx, %cr3");
*(uint32_t*)CURRENT_PAGE_DIR_ADDR = (uint32_t)currentPd;
// Call/jump to kernel
((void(*)(void))0xC0000000)();
bigError(0xffffffff);
}