Read framebuffer info from GRUB

kernel/kernel.c

@@ -1,5 +1,18 @@
 #include "../cpu/cpu_init.h"
+#include <grub/text_fb_info.h>
+#include <stdlib.h>
+#include "multiboot.h"
 
-void kmain() {
+void kmain(multiboot_info_t* header) {
   cpu_init();
+  text_fb_info info;
+  if (header->flags&MULTIBOOT_INFO_FRAMEBUFFER_INFO&&header->framebuffer_type==2) {
+    info.address=(char*)((header->framebuffer_addr&0xFFFFFFFF)+0xC0000000);
+    info.width=header->framebuffer_width;
+    info.height=header->framebuffer_height;
+  } else {
+    info.address=(char*)0xC00B8000;
+    info.width=80;
+    info.height=25;
+  }
 }

libc/grub/text_fb_info.h

@@ -0,0 +1,12 @@
+#ifndef GRUB_TEXT_FB_INFO_H
+#define GRUB_TEXT_FB_INFO_H
+
+#include <stdint.h>
+
+typedef struct {
+  char* address;
+  uint32_t width;
+  uint32_t height;
+} text_fb_info;
+
+#endif