Kernel: Don't use multiboot2 explicitly. Parse it to common structure

This allows support of multiple different bootloaders
2023-11-17 18:54:59 +02:00
parent 641a2dec00
commit 84040e64b8
10 changed files with 226 additions and 97 deletions
--- a/kernel/kernel/BootInfo.cpp
+++ b/kernel/kernel/BootInfo.cpp
@@ -0,0 +1,94 @@
+#include <kernel/BootInfo.h>
+
+#include <kernel/multiboot2.h>
+
+namespace Kernel
+{
+
+	BootInfo g_boot_info;
+
+	void parse_boot_info_multiboot2(uint32_t info)
+	{
+		const auto& multiboot2_info = *reinterpret_cast<const multiboot2_info_t*>(info);
+
+		for (const auto* tag = multiboot2_info.tags; tag->type != MULTIBOOT2_TAG_END; tag = tag->next())
+		{
+			if (tag->type == MULTIBOOT2_TAG_CMDLINE)
+			{
+				const auto& command_line_tag = *reinterpret_cast<const multiboot2_cmdline_tag_t*>(tag);
+				MUST(g_boot_info.command_line.append(command_line_tag.cmdline));
+			}
+			else if (tag->type == MULTIBOOT2_TAG_FRAMEBUFFER)
+			{
+				const auto& framebuffer_tag = *reinterpret_cast<const multiboot2_framebuffer_tag_t*>(tag);
+				g_boot_info.framebuffer.address	= framebuffer_tag.framebuffer_addr;
+				g_boot_info.framebuffer.pitch	= framebuffer_tag.framebuffer_pitch;
+				g_boot_info.framebuffer.width	= framebuffer_tag.framebuffer_width;
+				g_boot_info.framebuffer.height	= framebuffer_tag.framebuffer_height;
+				g_boot_info.framebuffer.bpp		= framebuffer_tag.framebuffer_bpp;
+				if (framebuffer_tag.framebuffer_type == MULTIBOOT2_FRAMEBUFFER_TYPE_RGB)
+					g_boot_info.framebuffer.type = FramebufferType::RGB;
+				else
+					g_boot_info.framebuffer.type = FramebufferType::UNKNOWN;
+			}
+			else if (tag->type == MULTIBOOT2_TAG_MMAP)
+			{
+				const auto& mmap_tag = *reinterpret_cast<const multiboot2_mmap_tag_t*>(tag);
+
+				const size_t entry_count = (mmap_tag.size - sizeof(multiboot2_mmap_tag_t)) / mmap_tag.entry_size;
+				
+				MUST(g_boot_info.memory_map_entries.resize(entry_count));
+
+				for (size_t i = 0; i < entry_count; i++)
+				{
+					const auto& mmap_entry = *reinterpret_cast<const multiboot2_mmap_entry_t*>(reinterpret_cast<uintptr_t>(tag) + sizeof(multiboot2_mmap_tag_t) + i * mmap_tag.entry_size);
+					dprintln("entry {16H} {16H} {8H}",
+						(uint64_t)mmap_entry.base_addr,
+						(uint64_t)mmap_entry.length,
+						(uint64_t)mmap_entry.type
+					);
+					g_boot_info.memory_map_entries[i].address	= mmap_entry.base_addr;
+					g_boot_info.memory_map_entries[i].length	= mmap_entry.length;
+					g_boot_info.memory_map_entries[i].type		= mmap_entry.type;
+				}
+			}
+		}
+	}
+
+	BAN::StringView get_early_boot_command_line_multiboot2(uint32_t info)
+	{
+		const auto& multiboot2_info = *reinterpret_cast<const multiboot2_info_t*>(info);
+		for (const auto* tag = multiboot2_info.tags; tag->type != MULTIBOOT2_TAG_END; tag = tag->next())
+			if (tag->type == MULTIBOOT2_TAG_CMDLINE)
+				return reinterpret_cast<const multiboot2_cmdline_tag_t*>(tag)->cmdline;
+		return {};
+	}
+
+	bool validate_boot_magic(uint32_t magic)
+	{
+		if (magic == MULTIBOOT2_MAGIC)
+			return true;
+		return false;	
+	}
+
+	void parse_boot_info(uint32_t magic, uint32_t info)
+	{
+		switch (magic)
+		{
+			case MULTIBOOT2_MAGIC:
+				return parse_boot_info_multiboot2(info);
+		}
+		ASSERT_NOT_REACHED();
+	}
+
+	BAN::StringView get_early_boot_command_line(uint32_t magic, uint32_t info)
+	{
+		switch (magic)
+		{
+			case MULTIBOOT2_MAGIC:
+				return get_early_boot_command_line_multiboot2(info);
+		}
+		ASSERT_NOT_REACHED();
+	}
+
+}