1 files changed, 66 insertions, 0 deletions
diff --git a/src/cpu_mode.rs b/src/cpu_mode.rs
new file mode 100644
index 0000000..9afa665
--- /dev/null
+++ b/src/cpu_mode.rs
@@ -0,0 +1,66 @@
+/*
+	Copyright 2021-2023 Gabriel Jensen.
+
+	This file is part of Luma.
+
+	Luma is free software: you can redistribute it
+	and/or modify it under the terms of the GNU
+	Affero General Public License as published by
+	the Free Software Foundation, either version 3
+	of the License, or (at your option) any later
+	version.
+
+	Luma 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
+	Affero General Public License for more details.
+
+	You should have received a copy of the GNU
+	Affero General Public License along with Luma.
+	If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#[repr(u8)]
+#[derive(Clone, Copy)]
+pub enum CpuMode {
+	User                 = 0b10000,
+	FastInterruptRequest = 0b10001,
+	InterruptRequest     = 0b10010,
+	Supervisor           = 0b10011,
+	Abort                = 0b10111,
+	Undefined            = 0b11011,
+	System               = 0b11111,
+}
+
+impl CpuMode {
+	pub fn from_raw(raw: u8) -> Self {
+		use CpuMode::*;
+
+		return match raw {
+			0b10000 => User,
+			0b10001 => FastInterruptRequest,
+			0b10010 => InterruptRequest,
+			0b10011 => Supervisor,
+			0b10111 => Abort,
+			0b11011 => Undefined,
+			0b11111 => System,
+
+			_ => panic!("invalid cpu mode {raw:#010b}"),
+		};
+	}
+
+	pub fn name(self) -> &'static str {
+		use CpuMode::*;
+
+		return match self {
+			Abort                => "abt",
+			FastInterruptRequest => "fiq",
+			InterruptRequest     => "irq",
+			Supervisor           => "svc",
+			System               => "sys",
+			Undefined            => "und",
+			User                 => "usr",
+		};
+	}
+}