Kernel: Rewrite whole AML parser

Now AML parsing is actually done while respecting namespaces and
scopes. I implemented the minimal functionality to parse qemu's AML.

Next step is to implement AML interpreting and then we can drop lai
as a dependency.

kernel/include/kernel/ACPI/AML/Region.h

@@ -0,0 +1,114 @@
+#pragma once
+
+#include <kernel/ACPI/AML/NamedObject.h>
+#include <kernel/ACPI/AML/Namespace.h>
+#include <kernel/ACPI/AML/ParseContext.h>
+
+namespace Kernel::ACPI::AML
+{
+
+	struct OpRegion : public NamedObject
+	{
+		enum class RegionSpace
+		{
+			SystemMemory = 0,
+			SystemIO = 1,
+			PCIConfig = 2,
+			EmbeddedController = 3,
+			SMBus = 4,
+			SystemCMOS = 5,
+			PCIBarTarget = 6,
+			IPMI = 7,
+			GeneralPurposeIO = 8,
+			GenericSerialBus = 9,
+			PCC = 10,
+		};
+		RegionSpace space;
+		uint64_t offset;
+		uint64_t length;
+
+		OpRegion(NameSeg name, RegionSpace space, uint64_t offset, uint64_t length)
+			: NamedObject(Node::Type::OpRegion, name), space(space), offset(offset), length(length)
+		{}
+
+		static ParseResult parse(AML::ParseContext& context)
+		{
+			ASSERT(context.aml_data.size() > 2);
+			ASSERT(static_cast<Byte>(context.aml_data[0]) == Byte::ExtOpPrefix);
+			ASSERT(static_cast<ExtOp>(context.aml_data[1]) == ExtOp::OpRegionOp);
+			context.aml_data = context.aml_data.slice(2);
+
+			auto name = NameString::parse(context.aml_data);
+			if (!name.has_value())
+				return ParseResult::Failure;
+
+			if (context.aml_data.size() < 1)
+				return ParseResult::Failure;
+			auto region_space = static_cast<RegionSpace>(context.aml_data[0]);
+			context.aml_data = context.aml_data.slice(1);
+
+			auto offset_result = AML::parse_object(context);
+			if (!offset_result.success())
+				return ParseResult::Failure;
+			auto offset = offset_result.node()->as_integer();
+			if (!offset.has_value())
+			{
+				AML_ERROR("OpRegion offset must be an integer");
+				return ParseResult::Failure;
+			}
+
+			auto length_result = AML::parse_object(context);
+			if (!length_result.success())
+				return ParseResult::Failure;
+			auto length = length_result.node()->as_integer();
+			if (!length.has_value())
+			{
+				AML_ERROR("OpRegion length must be an integer");
+				return ParseResult::Failure;
+			}
+
+			auto op_region = MUST(BAN::RefPtr<OpRegion>::create(
+				name->path.back(),
+				region_space,
+				offset.value(),
+				length.value()
+			));
+
+			if (!context.root_namespace->add_named_object(context.scope.span(), name.value(), op_region))
+				return ParseResult::Failure;
+
+#if AML_DEBUG_LEVEL >= 2
+			op_region->debug_print(0);
+			AML_DEBUG_PRINTLN("");
+#endif
+
+			return ParseResult::Success;
+		}
+
+		virtual void debug_print(int indent) const override
+		{
+			BAN::StringView region_space_name;
+			switch (space)
+			{
+				case RegionSpace::SystemMemory:			region_space_name = "SystemMemory"sv; break;
+				case RegionSpace::SystemIO:				region_space_name = "SystemIO"sv; break;
+				case RegionSpace::PCIConfig:			region_space_name = "PCIConfig"sv; break;
+				case RegionSpace::EmbeddedController:	region_space_name = "EmbeddedController"sv; break;
+				case RegionSpace::SMBus:				region_space_name = "SMBus"sv; break;
+				case RegionSpace::SystemCMOS:			region_space_name = "SystemCMOS"sv; break;
+				case RegionSpace::PCIBarTarget:			region_space_name = "PCIBarTarget"sv; break;
+				case RegionSpace::IPMI:					region_space_name = "IPMI"sv; break;
+				case RegionSpace::GeneralPurposeIO:		region_space_name = "GeneralPurposeIO"sv; break;
+				case RegionSpace::GenericSerialBus:		region_space_name = "GenericSerialBus"sv; break;
+				case RegionSpace::PCC:					region_space_name = "PCC"sv; break;
+				default: region_space_name = "Unknown"sv; break;
+			}
+			AML_DEBUG_PRINT_INDENT(indent);
+			AML_DEBUG_PRINT("OperationRegion(");
+			name.debug_print();
+			AML_DEBUG_PRINT(", {}, 0x{H}, 0x{H})", region_space_name, offset, length);
+		}
+
+	};
+
+}