feat: working bootloader and basic kernel (just dyes screen green)

2026-04-20 08:30:08 +04:00
parent 9b549d4184
commit 1ee5dcbd0b
9 changed files with 258 additions and 16 deletions
@@ -1,7 +1,144 @@
 #include "uefi/uefi.h" // IWYU pragma: keep
+#include "../../Common/bootinfo.h"

-int main() {
-    printf("Meow!\n");
-    while (1) __asm__ ("wfi");
-    return 0;
+void print(wchar_t* msg) {
+    ST->ConOut->OutputString(ST->ConOut, msg);
+}
+
+efi_status_t die() {
+    while(1) __asm__ volatile("wfi");
+    return EFI_ABORTED;
+}
+
+int compare_guid(efi_guid_t* a, efi_guid_t* b) {
+    uint8_t* p1 = (uint8_t*)a;
+    uint8_t* p2 = (uint8_t*)b;
+    for (int i = 0; i < 16; i++) {
+        if (p1[i] != p2[i]) return 0;
+    }
+    return 1;
+}
+
+int main()
+{
+    efi_gop_t* gop = NULL;
+    efi_guid_t gop_guid = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID;
+    ST->BootServices->LocateProtocol(&gop_guid, 0, (void**)&gop);
+
+    efi_guid_t dtb_guid = {0xb1b621d5, 0xf19c, 0x41a5, {0x83, 0x0b, 0xd9, 0x15, 0x2c, 0x69, 0xaa, 0xe0}};
+    void* dtbAddress = NULL;
+
+    for (uintn_t i = 0; i < ST->NumberOfTableEntries; i++) {
+        if (compare_guid(&ST->ConfigurationTable[i].VendorGuid, &dtb_guid)) {
+            dtbAddress = ST->ConfigurationTable[i].VendorTable;
+            break;
+        }
+    }
+
+    if (!dtbAddress) {
+        print(L"Failed to find DTB!\r\n");
+        return die();
+    }
+
+    efi_loaded_image_protocol_t* loaded_image;
+    efi_guid_t lip_guid = EFI_LOADED_IMAGE_PROTOCOL_GUID;
+    gBS->HandleProtocol(IM, &lip_guid, (void**)&loaded_image);
+
+    efi_simple_file_system_protocol_t* fs;
+    efi_guid_t sfsp_guid = EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID;
+    gBS->HandleProtocol(loaded_image->DeviceHandle, &sfsp_guid, (void**)&fs);
+
+    efi_file_handle_t* root;
+    fs->OpenVolume(fs, &root);
+
+    efi_file_handle_t* kernel_file;
+    uintn_t kinfo_size = 0;
+    efi_file_info_t* kfile_info = NULL;
+    efi_guid_t fi_guid = EFI_FILE_INFO_GUID;
+
+    efi_status_t status = root->Open(root, &kernel_file, L"ksOSKernel.bin", EFI_FILE_MODE_READ, 0);
+    if (EFI_ERROR(status)) {
+        print(L"Cant find ksOSKernel.bin\r\n");
+        return die();
+    }
+
+    status = kernel_file->GetInfo(kernel_file, &fi_guid, &kinfo_size, NULL);
+    if (status == EFI_BUFFER_TOO_SMALL) { 
+        gBS->AllocatePool(EfiLoaderData, kinfo_size, (void**)&kfile_info);
+        status = kernel_file->GetInfo(kernel_file, &fi_guid, &kinfo_size, kfile_info);
+    }
+
+    uint64_t kernel_size = kfile_info->FileSize;
+    uintn_t kernel_size_read = (uintn_t)kernel_size;
+    
+    uintn_t kernel_pages = (kernel_size + 0xFFF) / 0x1000;
+    efi_physical_address_t kernel_addr = 0; 
+    
+    status = gBS->AllocatePages(AllocateAnyPages, EfiLoaderData, kernel_pages, &kernel_addr);
+    if (EFI_ERROR(status)) {
+        print(L"Failed to allocate ANY memory for kernel!\r\n");
+        return die();
+    }
+
+    kernel_file->Read(kernel_file, &kernel_size_read, (void*)kernel_addr); \
+    printf("Kernel loaded at %p\r\n", (void*)kernel_addr);
+
+    Bootinfo* bootInfo = (Bootinfo*)malloc(sizeof(Bootinfo));
+    bootInfo->magic = BOOTINFO_MAGIC;
+
+    bootInfo->kernelInfo.kernelAddress = (void*)kernel_addr;
+    bootInfo->kernelInfo.kernelSize = kernel_size;
+
+    bootInfo->framebuffer.base = (BIUInt32*)gop->Mode->FrameBufferBase;
+    bootInfo->framebuffer.baseSize = gop->Mode->FrameBufferSize;
+    bootInfo->framebuffer.height = gop->Mode->Information->VerticalResolution;
+    bootInfo->framebuffer.width = gop->Mode->Information->HorizontalResolution;
+    bootInfo->framebuffer.pitch = gop->Mode->Information->PixelsPerScanLine;
+
+    bootInfo->dtb = dtbAddress;
+    printf("DTB located at: %p\r\n", (void*)dtbAddress);
+    
+    uintn_t map_size = 0;
+    efi_memory_descriptor_t *map = NULL;
+    uintn_t map_key;
+    uintn_t desc_size;
+    uint32_t desc_version;
+
+
+    print(L"Almost ready to jump :D. Working with memory map\r\n");
+
+    gBS->GetMemoryMap(&map_size, NULL, &map_key, &desc_size, &desc_version);
+    map_size += 4096;
+    // woah letsgoo
+    status = gBS->AllocatePool(EfiLoaderData, map_size, (void**)&map);
+    if (EFI_ERROR(status)) {
+        print(L"Failed to allocate pool\r\n");
+    }
+
+    do {
+        status = gBS->GetMemoryMap(&map_size, map, &map_key, &desc_size, &desc_version);
+        if (EFI_ERROR(status)) {
+            break;
+        }
+        
+        bootInfo->memoryMap.descriptorSize = desc_size;
+        bootInfo->memoryMap.descriptorVersion = desc_version;
+        bootInfo->memoryMap.mapSize = map_size;
+        bootInfo->memoryMap.mapKey = map_key;
+        bootInfo->memoryMap.map = map;
+
+        status = gBS->ExitBootServices(IM, map_key);
+        if (status == EFI_SUCCESS) {
+            break; // FUCK OFF;
+        }
+        map_size += 2 * desc_size; 
+    } while (EFI_ERROR(status));
+
+    typedef void (__attribute__((sysv_abi)) *kentry)(Bootinfo*);
+    kentry kmain = (kentry)kernel_addr;
+
+    kmain(bootInfo); // yay! :D
+
+
+    return EFI_SUCCESS;
 }