Print some multiboot2 information

1 files changed, 69 insertions, 7 deletions

diff --git a/kernel.cc b/kernel.cc
index 3df1903..ffc7180 100644
--- a/kernel.cc
+++ b/kernel.cc
@@ -1,6 +1,3 @@
-#include <stdlib.h>
-#include <types.h>
-
 /* Check if the compiler thinks you are targeting the wrong operating system. */
 #if defined(__linux__)
 #error "You are not using a cross-compiler"
@@ -11,16 +8,81 @@
 #error "This tutorial needs to be compiled with a ix86-elf compiler"
 #endif
 
+#include "multiboot2.h"
 #include "vga.h"
+#include <stdlib.h>
+#include <types.h>
 
-extern "C" void kernel_main(void) {
+extern "C" void kernel_main(uint32_t mb_magic, uint32_t mb_addr) {
   VGA terminal;
-  console_set(&terminal);
+  Console::set(&terminal);
 
   terminal.set_color(VGA::VGA_COLOR_CYAN, VGA::VGA_COLOR_BROWN);
-  terminal.write("Hello, kernel World! xxx--\n", "--xyxyxz\n", 10);
+  printk("Hello, kernel World!\n");
+
+  printk("multiboot magic: 0x", mb_magic,
+         mb_magic == MULTIBOOT2_BOOTLOADER_MAGIC ? " is valid" : " is invalid",
+         '\n');
+  printk("multiboot addr: 0x", mb_addr, '\n');
+
+  if (mb_addr & 7) {
+    printk("unaligned mbi\n");
+  }
+
+  struct multiboot_tag *tag;
+  const uint32_t size = *(unsigned *)mb_addr;
+  printk("Announced mbi size 0x", size, '\n');
+
+  for (tag = (struct multiboot_tag *)(mb_addr + 8);
+       tag->type != MULTIBOOT_TAG_TYPE_END;
+       tag = (struct multiboot_tag *)((multiboot_uint8_t *)tag +
+                                      ((tag->size + 7) & ~7))) {
+
+    switch (tag->type) {
+    case MULTIBOOT_TAG_TYPE_CMDLINE:
+      printk("Command line = [", ((struct multiboot_tag_string *)tag)->string,
+             "]\n");
+      break;
+    case MULTIBOOT_TAG_TYPE_BOOT_LOADER_NAME:
+      printk("Boot loader name = [",
+             ((struct multiboot_tag_string *)tag)->string, "]\n");
+      break;
+    case MULTIBOOT_TAG_TYPE_BASIC_MEMINFO:
+      printk("mem_lower = ",
+             ((struct multiboot_tag_basic_meminfo *)tag)->mem_lower, "KB\n",
+             "mem_upper = ",
+             ((struct multiboot_tag_basic_meminfo *)tag)->mem_upper, "KB\n");
+      break;
+    case MULTIBOOT_TAG_TYPE_BOOTDEV:
+      printk("Boot device 0x", ((struct multiboot_tag_bootdev *)tag)->biosdev,
+             " slice ", ((struct multiboot_tag_bootdev *)tag)->slice, " part ",
+             ((struct multiboot_tag_bootdev *)tag)->part, '\n');
+      break;
+    case MULTIBOOT_TAG_TYPE_MMAP: {
+      multiboot_memory_map_t *mmap;
+
+      printk("mmap\n");
+
+      for (mmap = ((struct multiboot_tag_mmap *)tag)->entries;
+           (multiboot_uint8_t *)mmap < (multiboot_uint8_t *)tag + tag->size;
+           mmap = (multiboot_memory_map_t *)((unsigned long)mmap +
+                                             ((struct multiboot_tag_mmap *)tag)
+                                                 ->entry_size))
+        printk(" base_addr = 0x", (unsigned)(mmap->addr >> 32), ' ',
+               (unsigned)(mmap->addr & 0xffffffff), " length = 0x",
+               (unsigned)(mmap->len >> 32), ' ',
+               (unsigned)(mmap->len & 0xffffffff), " type = 0x",
+               (unsigned)mmap->type, '\n');
+    } break;
+    default:
+      printk("Tag 0x", tag->type, ", Size 0x", tag->size, '\n');
+      break;
+    } // switch(tag->type)
+  }   // for(each tag)
 
-  printk("This is printk\n");
+  tag = (struct multiboot_tag *)((multiboot_uint8_t *)tag +
+                                 ((tag->size + 7) & ~7));
+  printk("Total mbi size 0x", (unsigned)tag - mb_addr, '\n');
 
   abort();
 }