get rsdp

gnu-efi/bootloader/main.c

@@ -119,8 +119,18 @@ typedef struct {
 	EFI_MEMORY_DESCRIPTOR* mMap;
 	UINTN mMapSize;
 	UINTN mMapDescriptorSize;
+	void* rsdp;
 } BootInfo;
 
+UINTN strcmp(CHAR8* a, CHAR8* b, UINTN length) {
+	for (UINTN i = 0; i < length; i++) {
+		if (*a != *b) {
+			return 0;
+		}
+	}
+	return 1;
+}
+
 EFI_STATUS efi_main (EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE* SystemTable) {
 
 	// sets up UEFI environment to be able to use
@@ -225,6 +235,20 @@ EFI_STATUS efi_main (EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE* SystemTable) {
 
 	}
 
+	// look for the acpi2 table
+	EFI_CONFIGURATION_TABLE* configTable = SystemTable->ConfigurationTable;
+	void* rsdp = NULL;
+	EFI_GUID Acpi2TableGuid = ACPI_20_TABLE_GUID;
+	for (UINTN index = 0; index < SystemTable->NumberOfTableEntries; index++) {
+		if (CompareGuid(&configTable[index].VendorGuid, &Acpi2TableGuid)) {
+			if (strcmp((CHAR8*)"RSD PTR ", (CHAR8*)configTable->VendorTable, 8)) {
+				rsdp = (void*)configTable->VendorTable;
+			}
+		}
+
+		configTable++;
+	}
+
 	// Run the kernel's main function! :D
 	void (*KernelStart)(BootInfo*) = ((__attribute__((sysv_abi)) void (*)(BootInfo*) ) header.e_entry);
 
@@ -234,6 +258,7 @@ EFI_STATUS efi_main (EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE* SystemTable) {
 	bootInfo.mMap = Map;
 	bootInfo.mMapSize = MapSize;
 	bootInfo.mMapDescriptorSize = DescriptorSize;
+	bootInfo.rsdp = rsdp;
 
 	SystemTable->BootServices->ExitBootServices(ImageHandle, MapKey);
 

kernel/src/kernel.cpp

@@ -3,6 +3,17 @@
 extern "C" void _start(BootInfo* bootInfo) {
 	KernelInfo kernelInfo = InitializeKernel(bootInfo);
 	PageTableManager* pageTableManager = kernelInfo.pageTableManager;
+
+	GlobalRenderer->Print(to_hstring((uint64_t)bootInfo->rsdp));
+	GlobalRenderer->Next();
+	GlobalRenderer->PutChar(*(uint8_t*)bootInfo->rsdp);
+	GlobalRenderer->PutChar(*((uint8_t*)bootInfo->rsdp + 1));
+	GlobalRenderer->PutChar(*((uint8_t*)bootInfo->rsdp + 2));
+	GlobalRenderer->PutChar(*((uint8_t*)bootInfo->rsdp + 3));
+	GlobalRenderer->PutChar(*((uint8_t*)bootInfo->rsdp + 4));
+	GlobalRenderer->PutChar(*((uint8_t*)bootInfo->rsdp + 5));
+	GlobalRenderer->PutChar(*((uint8_t*)bootInfo->rsdp + 6));
+	GlobalRenderer->PutChar(*((uint8_t*)bootInfo->rsdp + 7));
 	
 	while (true) {
 		ProcessMousePacket();

kernel/src/kernelUtil.h

@@ -19,6 +19,7 @@ struct BootInfo {
 	EFI_MEMORY_DESCRIPTOR* mMap;
 	uint64_t mMapSize;
 	uint64_t mMapDescriptorSize;
+	void* rsdp;
 };
 
 extern uint64_t _KernelStart;