[BOOT] Parse multiboot information

kernel/include/mem.h

@@ -13,6 +13,8 @@
   #include <stdint.h>
   #define V2P(a) ((uintptr_t)(a) - KERNEL_OFFSET)
   #define P2V(a) ((void *)((uintptr_t)(a) + KERNEL_OFFSET))
+  // returns an address n bytes after the target of pointer p
+  #define incptr(p, n) ((void *)(((uintptr_t)(p)) + (n)))
 #endif
 
 // Paging

kernel/include/multiboot.h

@@ -12,3 +12,66 @@
 #define MBOOT2_LENGTH (MultiBootHeaderEnd - MultiBootHeader)
 #define MBOOT2_CHECKSUM -(MBOOT2_MAGIC + MBOOT2_ARCH + MBOOT2_LENGTH)
 
+#ifndef __ASSEMBLER__
+#include <stdint.h>
+
+// MULTIBOOT 1
+  typedef struct {
+    uint32_t flags;
+    uint32_t mem_lower;
+    uint32_t mem_upper;
+    uint32_t boot_device;
+    uint32_t cmdline;
+    uint32_t mods_count;
+    uint32_t mods_addr;
+    uint32_t symbol_num;
+    uint32_t symbol_size;
+    uint32_t symbol_addr;
+    uint32_t symbol_shndx;
+    uint32_t mmap_len;
+    uint32_t mmap_addr;
+    uint32_t drives_len;
+    uint32_t drives_addr;
+    uint32_t config_table;
+    uint32_t bootloader_name;
+    uint32_t apm_table;
+    uint32_t vbe_control_info;
+    uint32_t vbe_mode_info;
+    uint32_t vbe_mode;
+    uint32_t vbe_interface_seg;
+    uint32_t vbe_interface_off;
+    uint32_t vbe_interface_len;
+  } mboot1_info;
+
+// MULTIBOOT 2
+
+  typedef struct {
+    uint32_t total_size;
+    uint32_t reserved;
+  } mboot2_tags_head;
+
+  typedef struct {
+    uint32_t type;
+    uint32_t size;
+    char data[];
+  } mboot2_tag_basic;
+
+
+  #define MBOOT2_CMDLINE 1
+  #define MBOOT2_BOOTLOADER 2
+
+  // Multiboot tags are padded to a multiple of 8 bytes
+  #define next_tag(tag) ((void *)((((uintptr_t)tag) + tag->size + 7) & ~0x7))
+
+  extern char *mboot_tags_type[];
+  struct mboot_data_st{
+    int version;
+    void *data;
+    char *commandline;
+    char *bootloader;
+  };
+  extern struct mboot_data_st mboot_data;
+
+  void multiboot_init(uint64_t magic, void *data);
+
+#endif