/* Copyright (C) 2021,2022 fef <owo@fef.moe>.  All rights reserved. */

#include <asm/common.h>
#include <gay/config.h>
#include <arch/multiboot.h>
#include <arch/page.h>

	.code32

	/* see ../config/kernel{32,64}.ld */
	.extern _image_start_phys
	.extern _kernel_end_phys
	.extern _image_end_phys

	.extern _setup /* setup{32,64}.S */

	.section .multiboot.data, "a", @progbits

	.align	MB2_HEADER_ALIGN
	.global header_start
header_start: /* struct mb2_header */
	/* magic */
	.long	MB2_HEADER_MAGIC
	/* architecture */
	.long	MB2_ARCHITECTURE_I386
	/* heaer_length */
	.long	header_end - header_start
	/* checksum */
	.long	(1 << 32) - MB2_HEADER_MAGIC - MB2_ARCHITECTURE_I386 - (header_end - header_start)

#if 0 /* TODO: implement graphics */
	.align	MB2_TAG_ALIGN
framebuffer_tag_start: /* struct mb2_header_tag_framebuffer */
	/* type */
	.short	MB2_HEADER_TAG_FRAMEBUFFER
	/* flags */
	.short	MB2_HEADER_TAG_OPTIONAL
	/* size */
	.long	framebuffer_tag_end - framebuffer_tag_start
	/* width */
	.long	1024
	/* height */
	.long	768
	/* depth */
	.long	32
framebuffer_tag_end:
#endif /* framebuffer disabled */

	.align	MB2_TAG_ALIGN
end_tag_start: /* struct mb2_header_tag */
	/* type */
        .short	MB2_HEADER_TAG_END
	/* flags */
        .short	0
	/* size */
        .long	end_tag_end - end_tag_start
end_tag_end:

header_end:
	.size header_start, . - header_start

	/*
	 * So, this is weird.
	 * For some reason, the multiboot header is omitted in the compiled
	 * binary if the entry point isn't in the same file (i've tried way
	 * too many times).  But, since the header is the same for both i386
	 * and amd64, we simply add this wrapper.
	 */
	.section .multiboot.text, "ax", @progbits
ASM_ENTRY(_start)
	cli
	jmp	_setup
ASM_END(_start)