Add ConfigMem FIRM stuff and GetSystemInfo modes for DDLC

src/core/kernel/kernel.cpp

@@ -258,6 +258,7 @@ void Kernel::duplicateHandle() {
 
 namespace SystemInfoType {
 	enum : u32 {
+		MemoryInformation = 0,
 		// Gets information related to Citra (We don't implement this, we just report this emulator is not Citra)
 		CitraInformation = 0x20000,
 		// Gets information related to this emulator
@@ -294,6 +295,22 @@ void Kernel::getSystemInfo() {
 
 	regs[0] = Result::Success;
 	switch (infoType) {
+		case SystemInfoType::MemoryInformation: {
+			switch (subtype) {
+				// Total used memory size in the APPLICATION memory region
+				case 1:
+					regs[1] = mem.getUsedUserMem();
+					regs[2] = 0;
+					break;
+
+				default:
+					Helpers::panic("GetSystemInfo: Unknown MemoryInformation subtype %x\n", subtype);
+					regs[0] = Result::FailurePlaceholder;
+					break;
+			}
+			break;
+		}
+
 		case SystemInfoType::CitraInformation: {
 			switch (subtype) {
 				case CitraInfoType::IsCitra: