From f9f12fffc6bc4c7d12a02c809a8237fccf6f452d Mon Sep 17 00:00:00 2001
From: Yoda Lee <lc85301@gmail.com>
Date: Tue, 2 May 2023 22:09:40 +0800
Subject: [PATCH] add virtio header of regsiter map, type and Status

---
 src/main.rs          |   1 +
 src/virtio/header.rs | 105 +++++++++++++++++++++++++++++++++++++++++++
 src/virtio/mod.rs    |   1 +
 3 files changed, 107 insertions(+)
 create mode 100644 src/virtio/header.rs
 create mode 100644 src/virtio/mod.rs

diff --git a/src/main.rs b/src/main.rs
index 5d7bf38..e386058 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -27,6 +27,7 @@ mod start;
 mod syscall;
 mod trap;
 mod uart;
+mod virtio;
 mod vm;
 
 use crate::cpu::{get_cpuid, init_cpu};
diff --git a/src/virtio/header.rs b/src/virtio/header.rs
new file mode 100644
index 0000000..1e825d9
--- /dev/null
+++ b/src/virtio/header.rs
@@ -0,0 +1,105 @@
+use bitflags::bitflags;
+use volatile_register::{RO, RW, WO};
+
+/// MMIO Device Register Layout
+///
+/// Ref: 4.2.2 MMIO Device Register Layout
+pub struct VirtioHeader {
+    // 0x00
+    magic: RO<u32>,
+    version: RO<u32>,
+    device_id: RO<u32>,
+    vendor_id: RO<u32>,
+    // 0x10
+    device_features: RO<u32>,
+    device_features_sel: WO<u32>,
+    _r0: [u32; 2],
+    // 0x20
+    driver_features: WO<u32>,
+    driver_features_sel: WO<u32>,
+    _r1: [u32; 2],
+    // 0x30
+    queue_sel: WO<u32>,
+    queue_num_max: RO<u32>,
+    queue_num: WO<u32>,
+    _r2: [u32; 1],
+    // 0x40
+    _r3: [u32; 1],
+    queue_ready: RW<u32>,
+    _r4: [u32; 2],
+    // 0x50
+    queue_notify: WO<u32>,
+    _r5: [u32; 3],
+    // 0x60
+    interrupt_status: RO<u32>,
+    interrupt_ack: WO<u32>,
+    _r6: [u32; 2],
+    // 0x70
+    status: RW<DeviceStatus>,
+    _r7: [u32; 3],
+    // 0x80
+    queue_desc_low: WO<u32>,
+    queue_desc_high: WO<u32>,
+    _r8: [u32; 2],
+    // 0x90
+    queue_driver_low: WO<u32>,
+    queue_driver_high: WO<u32>,
+    _r9: [u32; 2],
+    // 0xa0
+    queue_device_low: WO<u32>,
+    queue_device_high: WO<u32>,
+    _r10: [u32; 21],
+    // 0xfc
+    config_generation: RO<u32>,
+}
+
+impl VirtioHeader {
+    /// Verify header
+    pub fn verify(&self) -> bool {
+        self.magic.read() == 0x74726976
+            && self.version.read() == 2
+            && self.device_id.read() == 2
+            && self.vendor_id.read() == 0x554D4551
+    }
+}
+
+bitflags! {
+    pub struct DeviceStatus: u32 {
+        const ACKNOWLEDGE = 1;
+        const DRIVER = 2;
+        const DRIVER_OK = 4;
+        const FEATURES_OK = 8;
+        const DEVICE_NEEDS_RESET = 64;
+        const FAILED = 128;
+    }
+}
+
+/// Types of virtio devices.
+#[repr(u8)]
+#[derive(Debug, Eq, PartialEq)]
+#[allow(unused)]
+pub enum DeviceType {
+    Invalid = 0,
+    Network = 1,
+    Block = 2,
+    Console = 3,
+    EntropySource = 4,
+    MemoryBallooning = 5,
+    IoMemory = 6,
+    Rpmsg = 7,
+    ScsiHost = 8,
+    _9pTransport = 9,
+    Mac80211 = 10,
+    RprocSerial = 11,
+    VirtioCAIF = 12,
+    MemoryBalloon = 13,
+    GPU = 16,
+    TimerClock = 17,
+    Input = 18,
+    Socket = 19,
+    Crypto = 20,
+    SignalDistributionModule = 21,
+    Pstore = 22,
+    IOMMU = 23,
+    Memory = 24,
+}
diff --git a/src/virtio/mod.rs b/src/virtio/mod.rs
new file mode 100644
index 0000000..f505d68
--- /dev/null
+++ b/src/virtio/mod.rs
@@ -0,0 +1 @@
+pub mod header;