nvme: mi: Convert to deku

Use of bitfield was getting unwieldy. Deku is an ergonomic binary
marshalling crate that we're starting to use elsewhere as well.

Signed-off-by: Andrew Jeffery <andrew@codeconstruct.com.au>

Author: amboar

Cargo.lock

@@ -5,12 +5,14 @@ edition = "2024"
 license = "GPL-3.0-only"
 
 [dependencies]
-bitfield = "0.14.0"
 crc = "3.2.1"
+deku = { git = "https://github.com/CodeConstruct/deku.git", tag = "cc/deku-v0.19.1/no-alloc-3", default-features = false }
 heapless = "0.8.0"
 hmac = { version = "0.12.1", default-features = false }
 log = "0.4.22"
 mctp = { version = "0.2.0", default-features = false }
+num-derive = { version = "0.4", default-features = false }
+num-traits = { version = "0.2", default-features = false }
 sha2 = { version = "0.10.9", default-features = false }
 uuid = { version = "1.17.0", default-features = false }
 

Cargo.toml

@@ -3,10 +3,9 @@
  * Copyright (c) 2025 Code Construct
  */
 #![no_std]
-// bitfield needs this to cope with large structure sizes?
-#![recursion_limit = "512"]
 
 pub mod nvme;
+mod wire;
 
-#[macro_use]
-extern crate bitfield;
+extern crate deku;
+extern crate num_derive;

src/lib.rs

@@ -7,6 +7,11 @@ pub mod mi;
 use hmac::Mac;
 use uuid::Uuid;
 
+const MAX_CONTROLLERS: usize = 2;
+const MAX_NAMESPACES: usize = 2;
+const MAX_PORTS: usize = 2;
+const MAX_NIDTS: usize = 2;
+
 #[allow(dead_code)]
 #[derive(Clone, Copy, Debug, Eq, PartialEq)]
 #[repr(u8)]
@@ -97,19 +102,12 @@ impl Default for PCIePort {
 }
 
 #[allow(dead_code)]
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
-#[repr(u8)]
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
 enum SMBusFrequency {
-    FreqNotSupported = 0x00,
-    Freq100kHz = 0x01,
-    Freq400kHz = 0x02,
-    Freq1MHz = 0x03,
-}
-
-impl From<SMBusFrequency> for u8 {
-    fn from(freq: SMBusFrequency) -> Self {
-        freq as Self
-    }
+    FreqNotSupported,
+    Freq100kHz,
+    Freq400kHz,
+    Freq1MHz,
 }
 
 #[derive(Clone, Copy, Debug, Eq, PartialEq)]
@@ -367,43 +365,21 @@ impl SubsystemHealth {
     }
 }
 
-#[derive(Debug)]
-#[repr(u8)]
+#[derive(Clone, Copy, Debug)]
 pub enum CommandSetIdentifier {
-    NVMCommandSet = 0,
-    KeyValueCommandSet = 1,
-    ZonedNamespaceCommandSet = 2,
-    SubsystemLocalMemoryCommandSet = 3,
-    ComputationalProgramsCommandSet = 4,
-}
-
-impl CommandSetIdentifier {
-    fn id(&self) -> u8 {
-        // https://doc.rust-lang.org/reference/items/enumerations.html#r-items.enum.discriminant.access-memory
-        unsafe { *(self as *const Self as *const u8) }
-    }
+    NVMCommandSet,
+    KeyValueCommandSet,
+    ZonedNamespaceCommandSet,
+    SubsystemLocalMemoryCommandSet,
+    ComputationalProgramsCommandSet,
 }
 
-// NSID
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
-pub struct NamespaceId(u32);
-
-// NID: 5.1.13.2.3, Base v2.1
-#[derive(Debug)]
-#[repr(u8)]
+#[derive(Clone, Copy, Debug)]
 pub enum NamespaceIdentifierType {
-    Reserved = 0,
-    IEUID([u8; 8]) = 1,
-    NGUID([u8; 16]) = 2,
-    NUUID(Uuid) = 3,
-    CSI(CommandSetIdentifier) = 4,
-}
-
-impl NamespaceIdentifierType {
-    fn id(&self) -> u8 {
-        // https://doc.rust-lang.org/reference/items/enumerations.html#r-items.enum.discriminant.access-memory
-        unsafe { *(self as *const Self as *const u8) }
-    }
+    IEUID([u8; 8]),
+    NGUID([u8; 16]),
+    NUUID(Uuid),
+    CSI(CommandSetIdentifier),
 }
 
 #[derive(Debug)]
@@ -415,6 +391,10 @@ pub struct Namespace {
     nids: [NamespaceIdentifierType; 2],
 }
 
+// NSID
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct NamespaceId(u32);
+
 impl Namespace {
     fn generate_uuid(seed: &[u8], nsid: NamespaceId) -> Uuid {
         let mut hasher = hmac::Hmac::<sha2::Sha256>::new_from_slice(seed).unwrap();
@@ -438,10 +418,6 @@ impl Namespace {
     }
 }
 
-const MAX_CONTROLLERS: usize = 2;
-const MAX_NAMESPACES: usize = 2;
-const MAX_PORTS: usize = 2;
-
 #[derive(Clone, Copy, Debug)]
 pub struct SubsystemInfo {
     pub pci_vid: u16,