Add support for multiboot2

2025-07-15 17:29:19 +00:00 · 2023-05-10 21:50:11 +03:00
parent 79c6a5096d
commit f1dc3868ca
11 changed files with 343 additions and 97 deletions
--- a/Core/Memory/ReserveEssentials.cpp
+++ b/Core/Memory/ReserveEssentials.cpp
@@ -0,0 +1,122 @@
+/*
+   This file is part of Fennix Kernel.
+
+   Fennix Kernel is free software: you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation, either version 3 of
+   the License, or (at your option) any later version.
+
+   Fennix Kernel is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Fennix Kernel. If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#include <memory.hpp>
+
+#include <debug.h>
+#ifdef DEBUG
+#include <uart.hpp>
+#endif
+
+#if defined(a64)
+#include "../../Architecture/amd64/acpi.hpp"
+#elif defined(a32)
+#include "../../Architecture/i386/acpi.hpp"
+#elif defined(aa64)
+#endif
+
+#include "../../kernel.h"
+
+namespace Memory
+{
+	__no_sanitize("alignment") void Physical::ReserveEssentials()
+	{
+		debug("Reserving pages...");
+		/* The bootloader won't give us the entire mapping, so we
+		   reserve everything and then unreserve the usable pages. */
+		this->ReservePages(0, TO_PAGES(bInfo.Memory.Size));
+		debug("Unreserving usable pages...");
+
+		for (uint64_t i = 0; i < bInfo.Memory.Entries; i++)
+		{
+			if (bInfo.Memory.Entry[i].Type == Usable)
+				this->UnreservePages(bInfo.Memory.Entry[i].BaseAddress, TO_PAGES(bInfo.Memory.Entry[i].Length));
+		}
+
+		debug("Reserving 0x0-0xFFFFF range...");
+		// this->ReservePage((void *)0x0);						/* Trampoline stack, gdt, idt, etc... */
+		// this->ReservePages((void *)0x2000, 4);				/* TRAMPOLINE_START */
+
+		/* Reserve the lower part of memory. (0x0-0xFFFFF)
+		   This includes: BIOS, EBDA, VGA, SMP, etc...
+		   https://wiki.osdev.org/Memory_Map_(x86)
+		*/
+		this->ReservePages((void *)0x0, TO_PAGES(0xFFFFF));
+
+		debug("Reserving bitmap region %#lx-%#lx...", PageBitmap.Buffer, (void *)((uintptr_t)PageBitmap.Buffer + PageBitmap.Size));
+		this->ReservePages(PageBitmap.Buffer, TO_PAGES(PageBitmap.Size));
+
+		debug("Reserving kernel physical region %#lx-%#lx...", bInfo.Kernel.PhysicalBase, (void *)((uintptr_t)bInfo.Kernel.PhysicalBase + bInfo.Kernel.Size));
+		this->ReservePages(bInfo.Kernel.PhysicalBase, TO_PAGES(bInfo.Kernel.Size));
+
+		debug("Reserving kernel file and symbols...");
+		if (bInfo.Kernel.FileBase)
+			this->ReservePages(bInfo.Kernel.FileBase, TO_PAGES(bInfo.Kernel.Size));
+
+		if (bInfo.Kernel.Symbols.Num && bInfo.Kernel.Symbols.EntSize && bInfo.Kernel.Symbols.Shndx)
+			this->ReservePages((void *)bInfo.Kernel.Symbols.Sections, TO_PAGES(bInfo.Kernel.Symbols.Num * bInfo.Kernel.Symbols.EntSize));
+
+		debug("Reserving kernel modules...");
+
+		for (uint64_t i = 0; i < MAX_MODULES; i++)
+		{
+			if (bInfo.Modules[i].Address == 0x0)
+				continue;
+
+			debug("Reserving module %s (%#lx-%#lx)...", bInfo.Modules[i].CommandLine,
+				  bInfo.Modules[i].Address, (void *)((uintptr_t)bInfo.Modules[i].Address + bInfo.Modules[i].Size));
+
+			this->ReservePages((void *)bInfo.Modules[i].Address, TO_PAGES(bInfo.Modules[i].Size));
+		}
+
+#if defined(a86)
+		debug("Reserving RSDT region %#lx-%#lx...", bInfo.RSDP, (void *)((uintptr_t)bInfo.RSDP + sizeof(BootInfo::RSDPInfo)));
+		this->ReservePages(bInfo.RSDP, TO_PAGES(sizeof(BootInfo::RSDPInfo)));
+
+		ACPI::ACPI::ACPIHeader *ACPIPtr = nullptr;
+		bool XSDT = false;
+
+		if (bInfo.RSDP->Revision >= 2 && bInfo.RSDP->XSDTAddress)
+		{
+			ACPIPtr = (ACPI::ACPI::ACPIHeader *)(bInfo.RSDP->XSDTAddress);
+			XSDT = true;
+		}
+		else
+			ACPIPtr = (ACPI::ACPI::ACPIHeader *)(uintptr_t)bInfo.RSDP->RSDTAddress;
+
+		debug("Reserving RSDT...");
+		this->ReservePages((void *)bInfo.RSDP, TO_PAGES(sizeof(BootInfo::RSDPInfo)));
+
+		size_t TableSize = ((ACPIPtr->Length - sizeof(ACPI::ACPI::ACPIHeader)) / (XSDT ? 8 : 4));
+		debug("Reserving %d ACPI tables...", TableSize);
+
+		for (size_t t = 0; t < TableSize; t++)
+		{
+			// TODO: Should I be concerned about unaligned memory access?
+			ACPI::ACPI::ACPIHeader *SDTHdr = nullptr;
+			if (XSDT)
+				SDTHdr = (ACPI::ACPI::ACPIHeader *)(*(uint64_t *)((uint64_t)ACPIPtr + sizeof(ACPI::ACPI::ACPIHeader) + (t * 8)));
+			else
+				SDTHdr = (ACPI::ACPI::ACPIHeader *)(*(uint32_t *)((uint64_t)ACPIPtr + sizeof(ACPI::ACPI::ACPIHeader) + (t * 4)));
+
+			this->ReservePages(SDTHdr, TO_PAGES(SDTHdr->Length));
+		}
+
+#elif defined(aa64)
+#endif
+	}
+}