upgrade multiboot2 header

src/boot/main.c

@@ -7,24 +7,6 @@
 #include "panic.h"
 #include "util.h"
 
-static void *multiboot_find_tag(uptr multiboot_info, u32 type) {
-    uptr next = multiboot_info + 8;
-
-    while (true) {
-        multiboot_tag *tag = (multiboot_tag*)next;
-
-        if (tag->type == MULTIBOOT_TAG_TYPE_END) {
-            return NULL;
-        }
-
-        if (tag->type == type) {
-            return tag;
-        }
-
-        next = align_up(next + tag->size, MULTIBOOT_TAG_ALIGN);
-    }
-}
-
 #define MAX_REGIONS 64
 
 typedef struct {
@@ -39,7 +21,7 @@ static memory_region memory_regions[MAX_REGIONS] = {0};
 static size_t memory_region_count = 0;
 
 static void find_memory_regions(uptr multiboot_info) {
-    multiboot_tag_mmap *tag = multiboot_find_tag(multiboot_info, MULTIBOOT_TAG_TYPE_MMAP);
+    multiboot_tag_mmap *tag = multiboot_get_mmap(multiboot_info);
     if (tag == NULL) {
         boot_panic("Multiboot did not provide mmap tag");
     }

src/boot/multiboot2.c

@@ -0,0 +1,27 @@
+#include "multiboot2.h"
+
+#define INFO_DATA_OFFSET    8
+#define TAG_ALIGNMENT       8
+#define TAG_TYPE_OFFSET     0
+#define TAG_SIZE_OFFSET     4
+
+void *multiboot_get_tag(uptr multiboot_info, u32 type) {
+    uptr current = multiboot_info + INFO_DATA_OFFSET;
+
+    while (true) {
+        u32 tag_type = *(u32*)(current + TAG_TYPE_OFFSET);
+        u32 tag_size = *(u32*)(current + TAG_SIZE_OFFSET);
+
+        if (tag_type == MULTIBOOT_TAG_TYPE_END) {
+            break;
+        }
+
+        if (tag_type == type) {
+            return (void*)current;
+        }
+
+        current = align_up(current + tag_size, TAG_ALIGNMENT);
+    }
+
+    return NULL;
+}

src/boot/multiboot2.h

@@ -19,9 +19,8 @@
  */
 #pragma once
 
-#define MULTIBOOT_BOOTLOADER_MAGIC 0x36d76289
+#include <def.h>
-
+#include "util.h"
-#define MULTIBOOT_TAG_ALIGN 8
 
 #define MULTIBOOT_TAG_TYPE_END 0
 #define MULTIBOOT_TAG_TYPE_CMDLINE 1
@@ -47,27 +46,16 @@
 #define MULTIBOOT_TAG_TYPE_LOAD_BASE_ADDRESS 21
 
 typedef struct {
-    u8 red;
+    u32 type;
-    u8 green;
+    u32 size;
-    u8 blue;
+    char cmdline[0];
-} multiboot_color;
+} multiboot_tag_cmdline;
-
-#define MULTIBOOT_MEMORY_AVAILABLE 1
-#define MULTIBOOT_MEMORY_RESERVED 2
-#define MULTIBOOT_MEMORY_ACPI_RECLAIMABLE 3
-#define MULTIBOOT_MEMORY_NVS 4
-#define MULTIBOOT_MEMORY_BADRAM 5
 
 typedef struct {
     u32 type;
     u32 size;
-} multiboot_tag;
+    char bootloader_name[0];
-
+} multiboot_tag_bootloader_name;
-typedef struct {
-    u32 type;
-    u32 size;
-    char string[0];
-} multiboot_tag_string;
 
 typedef struct {
     u32 type;
@@ -92,6 +80,12 @@ typedef struct {
     u32 sub_partition;
 } multiboot_tag_bootdev;
 
+#define MULTIBOOT_MEMORY_AVAILABLE 1
+#define MULTIBOOT_MEMORY_RESERVED 2
+#define MULTIBOOT_MEMORY_ACPI_RECLAIMABLE 3
+#define MULTIBOOT_MEMORY_NVS 4
+#define MULTIBOOT_MEMORY_BADRAM 5
+
 typedef struct {
     u64 base_address;
     u64 length;
@@ -124,6 +118,12 @@ typedef struct {
 #define MULTIBOOT_FRAMEBUFFER_TYPE_RGB 1
 #define MULTIBOOT_FRAMEBUFFER_TYPE_EGA_TEXT 2
 
+typedef struct {
+    u8 red;
+    u8 green;
+    u8 blue;
+} multiboot_color;
+
 typedef struct {
     u32 type;
     u32 size;
@@ -199,13 +199,13 @@ typedef struct {
     u32 type;
     u32 size;
     u8 rsdp[0];
-} multiboot_tag_old_acpi;
+} multiboot_tag_acpi_old;
 
 typedef struct {
     u32 type;
     u32 size;
     u8 rsdp[0];
-} multiboot_tag_new_acpi;
+} multiboot_tag_acpi_new;
 
 typedef struct {
     u32 type;
@@ -238,3 +238,89 @@ typedef struct {
     u32 size;
     u32 load_base_address;
 } multiboot_tag_load_base_address;
+
+void *multiboot_get_tag(uptr multiboot_info, u32 type);
+
+static inline multiboot_tag_cmdline *multiboot_get_cmdline(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_CMDLINE);
+}
+
+static inline multiboot_tag_bootloader_name *multiboot_get_bootloader_name(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_BOOT_LOADER_NAME);
+}
+
+static inline multiboot_tag_module *multiboot_get_module(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_MODULE);
+}
+
+static inline multiboot_tag_basic_meminfo *multiboot_get_basic_meminfo(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_BASIC_MEMINFO);
+}
+
+static inline multiboot_tag_bootdev *multiboot_get_bootdev(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_BOOTDEV);
+}
+
+static inline multiboot_tag_mmap *multiboot_get_mmap(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_MMAP);
+}
+
+static inline multiboot_tag_vbe *multiboot_get_vbe(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_VBE);
+}
+
+static inline multiboot_tag_framebuffer *multiboot_get_framebuffer(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_FRAMEBUFFER);
+}
+
+static inline multiboot_tag_elf_sections *multiboot_get_elf_sections(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_ELF_SECTIONS);
+}
+
+static inline multiboot_tag_apm *multiboot_get_apm(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_APM);
+}
+
+static inline multiboot_tag_efi32 *multiboot_get_efi32(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_EFI32);
+}
+
+static inline multiboot_tag_efi64 *multiboot_get_efi64(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_EFI64);
+}
+
+static inline multiboot_tag_smbios *multiboot_get_smbios(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_SMBIOS);
+}
+
+static inline multiboot_tag_acpi_old *multiboot_get_acpi_old(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_ACPI_OLD);
+}
+
+static inline multiboot_tag_acpi_new *multiboot_get_acpi_new(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_ACPI_NEW);
+}
+
+static inline multiboot_tag_network *multiboot_get_network(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_NETWORK);
+}
+
+static inline multiboot_tag_efi_mmap *multiboot_get_efi_mmap(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_EFI_MMAP);
+}
+
+static inline bool multiboot_get_efi_bs(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_EFI_BS) != NULL;
+}
+
+static inline multiboot_tag_efi32_ih *multiboot_get_efi32_ih(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_EFI32_IH);
+}
+
+static inline multiboot_tag_efi64_ih *multiboot_get_efi64_ih(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_EFI64_IH);
+}
+
+static inline multiboot_tag_load_base_address *multiboot_get_load_base_address(uptr multiboot_info) {
+    return multiboot_get_tag(multiboot_info, MULTIBOOT_TAG_TYPE_LOAD_BASE_ADDRESS);
+}