Got memory map almost working

This commit is contained in:
2025-03-19 11:25:45 +01:00
parent 883cd5c1d4
commit 05561cd857
6 changed files with 99 additions and 44 deletions
+27 -11
View File
@@ -9,25 +9,41 @@
#define BOOT_MB2 2 // MultiBoot 2
#define BOOT_LIMINE 3 // Limine
struct boot_memmapEntry {
uint64_t base;
uint64_t size;
uint32_t type;
uint32_t attr;
};
// Memmap region types
#define BOOT_MMAP_AVAILABLE 1
#define BOOT_MMAP_RESERVED 2
#define BOOT_MMAP_ACPI_RECLAIM 3
#define BOOT_MMAP_NVS 4
#define BOOT_MMAP_BADRAM 5
// A memory map entry
struct boot_memmap {
uint32_t skip; // Used for skipping (may be padded for alignment)
uint64_t base; // Memory region address
uint64_t size; // Memory region length
uint32_t type; // Memory region type
} __packed;
/*
* Some values may not be provided by the bootloader, in this case
* pointers will be NULL and integer values will be 0 if applicable.
* Some unprovided values may also be implied. Eg.:
* If 'memmap = NULL' then 'memmapLen' doesn't matter.
*/
struct boot_info {
uint32_t memLower;
uint32_t memUpper;
struct boot_memmapEntry* memmap;
uint8_t bootDrive;
uint8_t bootPart1;
uint8_t bootPart2;
uint8_t bootPart3;
char* cmdline;
uint32_t memmap;
size_t memmapLen;
};
char* bootname;
} __packed;
extern struct boot_info bootloader;
/*
* This functions arguments depend on the boot protocol provided.
@@ -36,9 +52,9 @@ struct boot_info {
*/
int boot_init(int type, ...);
int boot_init_mb1(void* ptr, uint32_t magic);
int boot_initMB1(void* ptr, uint32_t magic);
// TODO:
// int boot_init_mb2(...);
// int boot_init_limine(...);
// int boot_initMB2(...);
// int boot_initLimine(...);
#endif
+6 -5
View File
@@ -7,11 +7,12 @@
/*
* Variable arguments
*/
typedef void* va_list;
#define __va_align(size) ((size + sizeof(int) - 1) & ~(sizeof(int) - 1))
#define va_start(ap, param) (void)((ap) = (char*)(&(param) + 1))
#define va_end(ap) (void)((ap) = 0)
#define va_arg(ap, type) (*(type*)(((ap) += __va_align(sizeof(type))) - sizeof(type)))
typedef char* va_list;
#define __VA_ALIGN 4
#define __va_align(_t) (((sizeof(_t) + __VA_ALIGN - 1) / __VA_ALIGN) * __VA_ALIGN)
#define va_start(_ap, _arg) ((_ap) = (char*)(&(_arg) + 1))
#define va_arg(_ap, _type) (*(_type*)((_ap += __va_align(_type)) - __va_align(_type)))
#define va_end(_ap) (void)((_ap) = 0)
/*
* Utility macros
+38 -25
View File
@@ -2,46 +2,59 @@
#include <multiboot.h>
#include <kernel.h>
struct boot_info bootloader = { 0 };
struct boot_info bootloader;
// TODO:
int boot_init(int type, ...) {
va_list args;
va_start(args, type);
switch (type) {
case BOOT_UNKNOWN: return 1;
case BOOT_MB1: return boot_init_mb1(va_arg(args, void*), va_arg(args, uint32_t));
case BOOT_MB2: return 1;
case BOOT_LIMINE: return 1;
}
// We got an invalid boot protocol
return 1;
}
int boot_init_mb1(void* ptr, uint32_t magic) {
int boot_initMB1(void* ptr, uint32_t magic) {
multiboot_info_t* mbi = ptr;
if (magic != 0xBADB002) return 1;
if (magic != MULTIBOOT_BOOTLOADER_MAGIC) return 1;
// Memory info
// mem_* fields are valid
if (mbi->flags & MULTIBOOT_INFO_MEMORY) {
bootloader.memLower = mbi->mem_lower;
bootloader.memUpper = mbi->mem_upper;
}
// Memory map
if (mbi->flags & MULTIBOOT_INFO_MEM_MAP) {
uint32_t memmap = mbi->mmap_addr;
uint32_t offset = 0;
while (offset < mbi->mmap_length) {
multiboot_memory_map_t* entry = (multiboot_memory_map_t*)(memmap + offset);
offset += entry->size;
}
// boot_device is valid
if (mbi->flags & MULTIBOOT_INFO_BOOTDEV) {
bootloader.bootDrive = (mbi->boot_device & 0xff000000) >> 24;
bootloader.bootPart1 = (mbi->boot_device & 0x00ff0000) >> 16;
bootloader.bootPart2 = (mbi->boot_device & 0x0000ff00) >> 8;
bootloader.bootPart3 = (mbi->boot_device & 0x000000ff);
}
// cmdline is valid
if (mbi->flags & MULTIBOOT_INFO_CMDLINE) {
bootloader.cmdline = (char*)mbi->cmdline;
}
// TODO: mods
// TODO: a.out symbol table
// TODO: ELF symbol table
// mmap_* fields are valid
if (mbi->flags & MULTIBOOT_INFO_MEM_MAP) {
bootloader.memmap = mbi->mmap_addr;
bootloader.memmapLen = mbi->mmap_length;
}
// TODO: drives_*
// TODO: config_table
// boot_loader_name is valid
if (mbi->flags & MULTIBOOT_INFO_BOOT_LOADER_NAME) {
bootloader.bootname = (char*)mbi->boot_loader_name;
}
// TODO: APM table
// TODO: VBE table
// TODO: Framebuffer
return 0;
}
+22 -2
View File
@@ -7,11 +7,13 @@
__noreturn
void kmain(void* ptr, uint32_t magic) {
if (boot_init(BOOT_MB1, ptr, magic) != 0) panic("Unsupporred bootloader.");
if (boot_initMB1(ptr, magic) != 0) panic("Unsupporred bootloader.");
// Serial console for debugging
serial_init(COM1);
debugf("\x1b[H\x1b[J\x1b[0mkern. \x1b[35m(serial console)\x1b[0m\n\n");
// ESC[H moves cursor to (0,0), ESC[J clears from cursor to end of screen
// ESC[<x>m sets graphics mode, 0 - reset, 36 - cyan
debugf("\x1b[H\x1b[J\x1b[0mkern. \x1b[36m(serial console)\x1b[0m\n\n");
// VGA tty thingy
tty_init();
@@ -26,6 +28,24 @@ void kmain(void* ptr, uint32_t magic) {
// pag_init();
debugf("Basic initialization complete!\n");
struct boot_memmap* entry;
for (
entry = (struct boot_memmap*)bootloader.memmap;
(uint64_t)entry < bootloader.memmap + bootloader.memmapLen;
entry = (struct boot_memmap*)((uint64_t)entry + entry->skip + sizeof(entry))
) {
debugf("[Region] base: %x size: %x b type: ", entry->base, entry->size);
switch (entry->type) {
case BOOT_MMAP_AVAILABLE: debugf("Available\n"); break;
case BOOT_MMAP_RESERVED: debugf("Reserved\n"); break;
case BOOT_MMAP_ACPI_RECLAIM: debugf("ACPI Reclaim\n"); break;
case BOOT_MMAP_NVS: debugf("NVS\n"); break;
case BOOT_MMAP_BADRAM: debugf("Bad RAM\n"); break;
default: debugf("Invalid type\n"); break;
}
}
panic("kmain() reached end.");