From d30d37e356a7e5339c353b2aec94aa9eee59d8c6 Mon Sep 17 00:00:00 2001
From: Matthew Ettler <mattettler@protonmail.com>
Date: Sun, 28 Jul 2024 06:37:53 -0600
Subject: [PATCH] feat(std.os.uefi.protocol): add Serial IO

---
 lib/std/os/uefi/protocol.zig           |  2 +
 lib/std/os/uefi/protocol/serial_io.zig | 82 ++++++++++++++++++++++++++
 2 files changed, 84 insertions(+)
 create mode 100644 lib/std/os/uefi/protocol/serial_io.zig

diff --git a/lib/std/os/uefi/protocol.zig b/lib/std/os/uefi/protocol.zig
index 4f63cb814a95..6f895177f9cf 100644
--- a/lib/std/os/uefi/protocol.zig
+++ b/lib/std/os/uefi/protocol.zig
@@ -14,6 +14,8 @@ pub const SimpleTextOutput = @import("protocol/simple_text_output.zig").SimpleTe
 pub const SimplePointer = @import("protocol/simple_pointer.zig").SimplePointer;
 pub const AbsolutePointer = @import("protocol/absolute_pointer.zig").AbsolutePointer;
 
+pub const SerialIo = @import("protocol/serial_io.zig").SerialIo;
+
 pub const GraphicsOutput = @import("protocol/graphics_output.zig").GraphicsOutput;
 
 pub const edid = @import("protocol/edid.zig");
diff --git a/lib/std/os/uefi/protocol/serial_io.zig b/lib/std/os/uefi/protocol/serial_io.zig
new file mode 100644
index 000000000000..a7d9b302193d
--- /dev/null
+++ b/lib/std/os/uefi/protocol/serial_io.zig
@@ -0,0 +1,82 @@
+const std = @import("std");
+const uefi = std.os.uefi;
+const Guid = uefi.Guid;
+const Status = uefi.Status;
+const cc = uefi.cc;
+
+pub const SerialIo = extern struct {
+    revision: u64,
+    _reset: *const fn (*const SerialIo) callconv(cc) Status,
+    _set_attribute: *const fn (*const SerialIo, u64, u32, u32, ParityType, u8, StopBitsType) callconv(cc) Status,
+    _set_control: *const fn (*const SerialIo, u32) callconv(cc) Status,
+    _get_control: *const fn (*const SerialIo, *u32) callconv(cc) Status,
+    _write: *const fn (*const SerialIo, *usize, *anyopaque) callconv(cc) Status,
+    _read: *const fn (*const SerialIo, *usize, *anyopaque) callconv(cc) Status,
+    mode: *Mode,
+    device_type_guid: ?*Guid,
+
+    ///Resets the serial device.
+    pub fn reset(self: *const SerialIo) Status {
+        return self._reset(self);
+    }
+
+    ///Sets the baud rate, receive FIFO depth, transmit/receive time out, parity, data bits, and stop bits on a serial device.
+    pub fn setAttribute(self: *const SerialIo, baudRate: u64, receiverFifoDepth: u32, timeout: u32, parity: ParityType, dataBits: u8, stopBits: StopBitsType) Status {
+        return self._set_attribute(self, baudRate, receiverFifoDepth, timeout, parity, dataBits, stopBits);
+    }
+
+    ///Sets the control bits on a serial device.
+    pub fn setControl(self: *const SerialIo, control: u32) Status {
+        return self._set_control(self, control);
+    }
+
+    ///Retrieves the status of the control bits on a serial device.
+    pub fn getControl(self: *const SerialIo, control: *u32) Status {
+        return self._get_control(self, control);
+    }
+
+    ///Writes data to a serial device.
+    pub fn write(self: *const SerialIo, bufferSize: *usize, buffer: *anyopaque) Status {
+        return self._write(self, bufferSize, buffer);
+    }
+
+    ///Reads data from a serial device.
+    pub fn read(self: *const SerialIo, bufferSize: *usize, buffer: *anyopaque) Status {
+        return self._read(self, bufferSize, buffer);
+    }
+
+    pub const guid align(8) = Guid{
+        .time_low = 0xBB25CF6F,
+        .time_mid = 0xF1D4,
+        .time_high_and_version = 0x11D2,
+        .clock_seq_high_and_reserved = 0x9a,
+        .clock_seq_low = 0x0c,
+        .node = [_]u8{ 0x00, 0x90, 0x27, 0x3f, 0xc1, 0xfd },
+    };
+
+    pub const ParityType = enum(u32) {
+        DefaultParity,
+        NoParity,
+        EvenParity,
+        OddParity,
+        MarkParity,
+        SpaceParity,
+    };
+
+    pub const StopBitsType = enum(u32) {
+        DefaultStopBits,
+        OneStopBit,
+        OneFiveStopBits,
+        TwoStopBits,
+    };
+
+    pub const Mode = extern struct {
+        control_mask: u32,
+        timeout: u32,
+        baud_rate: u64,
+        receive_fifo_depth: u32,
+        data_bits: u32,
+        parity: u32,
+        stop_bits: u32,
+    };
+};