[PATCH v2 3/3] gpu: nova-core: switch to kernel bitfield macro

[Alexandre Courbot]

Replace uses of the Nova-internal `bitfield!` macro by the kernel one,
and remove the now-unneeded local macro.

Signed-off-by: Alexandre Courbot <acourbot@xxxxxxxxxx>
---
 drivers/gpu/nova-core/bitfield.rs  | 329 -------------------------------------
 drivers/gpu/nova-core/gsp/fw.rs    |  15 +-
 drivers/gpu/nova-core/nova_core.rs |   3 -
 3 files changed, 8 insertions(+), 339 deletions(-)

diff --git a/drivers/gpu/nova-core/bitfield.rs b/drivers/gpu/nova-core/bitfield.rs
deleted file mode 100644
index 02efdcf78d89..000000000000
--- a/drivers/gpu/nova-core/bitfield.rs
+++ /dev/null
@@ -1,329 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-
-//! Bitfield library for Rust structures
-//!
-//! Support for defining bitfields in Rust structures. Also used by the [`register!`] macro.
-
-/// Defines a struct with accessors to access bits within an inner unsigned integer.
-///
-/// # Syntax
-///
-/// ```rust
-/// use nova_core::bitfield;
-///
-/// #[derive(Debug, Clone, Copy, Default)]
-/// enum Mode {
-///     #[default]
-///     Low = 0,
-///     High = 1,
-///     Auto = 2,
-/// }
-///
-/// impl TryFrom<u8> for Mode {
-///     type Error = u8;
-///     fn try_from(value: u8) -> Result<Self, Self::Error> {
-///         match value {
-///             0 => Ok(Mode::Low),
-///             1 => Ok(Mode::High),
-///             2 => Ok(Mode::Auto),
-///             _ => Err(value),
-///         }
-///     }
-/// }
-///
-/// impl From<Mode> for u8 {
-///     fn from(mode: Mode) -> u8 {
-///         mode as u8
-///     }
-/// }
-///
-/// #[derive(Debug, Clone, Copy, Default)]
-/// enum State {
-///     #[default]
-///     Inactive = 0,
-///     Active = 1,
-/// }
-///
-/// impl From<bool> for State {
-///     fn from(value: bool) -> Self {
-///         if value { State::Active } else { State::Inactive }
-///     }
-/// }
-///
-/// impl From<State> for bool {
-///     fn from(state: State) -> bool {
-///         match state {
-///             State::Inactive => false,
-///             State::Active => true,
-///         }
-///     }
-/// }
-///
-/// bitfield! {
-///     pub struct ControlReg(u32) {
-///         7:7 state as bool => State;
-///         3:0 mode as u8 ?=> Mode;
-///     }
-/// }
-/// ```
-///
-/// This generates a struct with:
-/// - Field accessors: `mode()`, `state()`, etc.
-/// - Field setters: `set_mode()`, `set_state()`, etc. (supports chaining with builder pattern).
-///   Note that the compiler will error out if the size of the setter's arg exceeds the
-///   struct's storage size.
-/// - Debug and Default implementations.
-///
-/// Note: Field accessors and setters inherit the same visibility as the struct itself.
-/// In the example above, both `mode()` and `set_mode()` methods will be `pub`.
-///
-/// Fields are defined as follows:
-///
-/// - `as <type>` simply returns the field value casted to <type>, typically `u32`, `u16`, `u8` or
-///   `bool`. Note that `bool` fields must have a range of 1 bit.
-/// - `as <type> => <into_type>` calls `<into_type>`'s `From::<<type>>` implementation and returns
-///   the result.
-/// - `as <type> ?=> <try_into_type>` calls `<try_into_type>`'s `TryFrom::<<type>>` implementation
-///   and returns the result. This is useful with fields for which not all values are valid.
-macro_rules! bitfield {
-    // Main entry point - defines the bitfield struct with fields
-    ($vis:vis struct $name:ident($storage:ty) $(, $comment:literal)? { $($fields:tt)* }) => {
-        bitfield!(@core $vis $name $storage $(, $comment)? { $($fields)* });
-    };
-
-    // All rules below are helpers.
-
-    // Defines the wrapper `$name` type, as well as its relevant implementations (`Debug`,
-    // `Default`, and conversion to the value type) and field accessor methods.
-    (@core $vis:vis $name:ident $storage:ty $(, $comment:literal)? { $($fields:tt)* }) => {
-        $(
-        #[doc=$comment]
-        )?
-        #[repr(transparent)]
-        #[derive(Clone, Copy)]
-        $vis struct $name($storage);
-
-        impl ::core::convert::From<$name> for $storage {
-            fn from(val: $name) -> $storage {
-                val.0
-            }
-        }
-
-        bitfield!(@fields_dispatcher $vis $name $storage { $($fields)* });
-    };
-
-    // Captures the fields and passes them to all the implementers that require field information.
-    //
-    // Used to simplify the matching rules for implementers, so they don't need to match the entire
-    // complex fields rule even though they only make use of part of it.
-    (@fields_dispatcher $vis:vis $name:ident $storage:ty {
-        $($hi:tt:$lo:tt $field:ident as $type:tt
-            $(?=> $try_into_type:ty)?
-            $(=> $into_type:ty)?
-            $(, $comment:literal)?
-        ;
-        )*
-    }
-    ) => {
-        bitfield!(@field_accessors $vis $name $storage {
-            $(
-                $hi:$lo $field as $type
-                $(?=> $try_into_type)?
-                $(=> $into_type)?
-                $(, $comment)?
-            ;
-            )*
-        });
-        bitfield!(@debug $name { $($field;)* });
-        bitfield!(@default $name { $($field;)* });
-    };
-
-    // Defines all the field getter/setter methods for `$name`.
-    (
-        @field_accessors $vis:vis $name:ident $storage:ty {
-        $($hi:tt:$lo:tt $field:ident as $type:tt
-            $(?=> $try_into_type:ty)?
-            $(=> $into_type:ty)?
-            $(, $comment:literal)?
-        ;
-        )*
-        }
-    ) => {
-        $(
-            bitfield!(@check_field_bounds $hi:$lo $field as $type);
-        )*
-
-        #[allow(dead_code)]
-        impl $name {
-            $(
-            bitfield!(@field_accessor $vis $name $storage, $hi:$lo $field as $type
-                $(?=> $try_into_type)?
-                $(=> $into_type)?
-                $(, $comment)?
-                ;
-            );
-            )*
-        }
-    };
-
-    // Boolean fields must have `$hi == $lo`.
-    (@check_field_bounds $hi:tt:$lo:tt $field:ident as bool) => {
-        #[allow(clippy::eq_op)]
-        const _: () = {
-            ::kernel::build_assert!(
-                $hi == $lo,
-                concat!("boolean field `", stringify!($field), "` covers more than one bit")
-            );
-        };
-    };
-
-    // Non-boolean fields must have `$hi >= $lo`.
-    (@check_field_bounds $hi:tt:$lo:tt $field:ident as $type:tt) => {
-        #[allow(clippy::eq_op)]
-        const _: () = {
-            ::kernel::build_assert!(
-                $hi >= $lo,
-                concat!("field `", stringify!($field), "`'s MSB is smaller than its LSB")
-            );
-        };
-    };
-
-    // Catches fields defined as `bool` and convert them into a boolean value.
-    (
-        @field_accessor $vis:vis $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident as bool
-            => $into_type:ty $(, $comment:literal)?;
-    ) => {
-        bitfield!(
-            @leaf_accessor $vis $name $storage, $hi:$lo $field
-            { |f| <$into_type>::from(f != 0) }
-            bool $into_type => $into_type $(, $comment)?;
-        );
-    };
-
-    // Shortcut for fields defined as `bool` without the `=>` syntax.
-    (
-        @field_accessor $vis:vis $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident as bool
-            $(, $comment:literal)?;
-    ) => {
-        bitfield!(
-            @field_accessor $vis $name $storage, $hi:$lo $field as bool => bool $(, $comment)?;
-        );
-    };
-
-    // Catches the `?=>` syntax for non-boolean fields.
-    (
-        @field_accessor $vis:vis $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident as $type:tt
-            ?=> $try_into_type:ty $(, $comment:literal)?;
-    ) => {
-        bitfield!(@leaf_accessor $vis $name $storage, $hi:$lo $field
-            { |f| <$try_into_type>::try_from(f as $type) } $type $try_into_type =>
-            ::core::result::Result<
-                $try_into_type,
-                <$try_into_type as ::core::convert::TryFrom<$type>>::Error
-            >
-            $(, $comment)?;);
-    };
-
-    // Catches the `=>` syntax for non-boolean fields.
-    (
-        @field_accessor $vis:vis $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident as $type:tt
-            => $into_type:ty $(, $comment:literal)?;
-    ) => {
-        bitfield!(@leaf_accessor $vis $name $storage, $hi:$lo $field
-            { |f| <$into_type>::from(f as $type) } $type $into_type => $into_type $(, $comment)?;);
-    };
-
-    // Shortcut for non-boolean fields defined without the `=>` or `?=>` syntax.
-    (
-        @field_accessor $vis:vis $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident as $type:tt
-            $(, $comment:literal)?;
-    ) => {
-        bitfield!(
-            @field_accessor $vis $name $storage, $hi:$lo $field as $type => $type $(, $comment)?;
-        );
-    };
-
-    // Generates the accessor methods for a single field.
-    (
-        @leaf_accessor $vis:vis $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident
-            { $process:expr } $prim_type:tt $to_type:ty => $res_type:ty $(, $comment:literal)?;
-    ) => {
-        ::kernel::macros::paste!(
-        const [<$field:upper _RANGE>]: ::core::ops::RangeInclusive<u8> = $lo..=$hi;
-        const [<$field:upper _MASK>]: $storage = {
-            // Generate mask for shifting
-            match ::core::mem::size_of::<$storage>() {
-                1 => ::kernel::bits::genmask_u8($lo..=$hi) as $storage,
-                2 => ::kernel::bits::genmask_u16($lo..=$hi) as $storage,
-                4 => ::kernel::bits::genmask_u32($lo..=$hi) as $storage,
-                8 => ::kernel::bits::genmask_u64($lo..=$hi) as $storage,
-                _ => ::kernel::build_error!("Unsupported storage type size")
-            }
-        };
-        const [<$field:upper _SHIFT>]: u32 = $lo;
-        );
-
-        $(
-        #[doc="Returns the value of this field:"]
-        #[doc=$comment]
-        )?
-        #[inline(always)]
-        $vis fn $field(self) -> $res_type {
-            ::kernel::macros::paste!(
-            const MASK: $storage = $name::[<$field:upper _MASK>];
-            const SHIFT: u32 = $name::[<$field:upper _SHIFT>];
-            );
-            let field = ((self.0 & MASK) >> SHIFT);
-
-            $process(field)
-        }
-
-        ::kernel::macros::paste!(
-        $(
-        #[doc="Sets the value of this field:"]
-        #[doc=$comment]
-        )?
-        #[inline(always)]
-        $vis fn [<set_ $field>](mut self, value: $to_type) -> Self {
-            const MASK: $storage = $name::[<$field:upper _MASK>];
-            const SHIFT: u32 = $name::[<$field:upper _SHIFT>];
-            let value = ($storage::from($prim_type::from(value)) << SHIFT) & MASK;
-            self.0 = (self.0 & !MASK) | value;
-
-            self
-        }
-        );
-    };
-
-    // Generates the `Debug` implementation for `$name`.
-    (@debug $name:ident { $($field:ident;)* }) => {
-        impl ::kernel::fmt::Debug for $name {
-            fn fmt(&self, f: &mut ::kernel::fmt::Formatter<'_>) -> ::kernel::fmt::Result {
-                f.debug_struct(stringify!($name))
-                    .field("<raw>", &::kernel::prelude::fmt!("{:#x}", &self.0))
-                $(
-                    .field(stringify!($field), &self.$field())
-                )*
-                    .finish()
-            }
-        }
-    };
-
-    // Generates the `Default` implementation for `$name`.
-    (@default $name:ident { $($field:ident;)* }) => {
-        /// Returns a value for the bitfield where all fields are set to their default value.
-        impl ::core::default::Default for $name {
-            fn default() -> Self {
-                let value = Self(Default::default());
-
-                ::kernel::macros::paste!(
-                $(
-                let value = value.[<set_ $field>](Default::default());
-                )*
-                );
-
-                value
-            }
-        }
-    };
-}
diff --git a/drivers/gpu/nova-core/gsp/fw.rs b/drivers/gpu/nova-core/gsp/fw.rs
index 0c8a74f0e8ac..a7f75368c90e 100644
--- a/drivers/gpu/nova-core/gsp/fw.rs
+++ b/drivers/gpu/nova-core/gsp/fw.rs
@@ -9,6 +9,7 @@
 use core::ops::Range;
 
 use kernel::{
+    bitfield,
     dma::Coherent,
     prelude::*,
     ptr::{
@@ -17,8 +18,8 @@
         KnownSize, //
     },
     sizes::{
-        SZ_128K,
-        SZ_1M, //
+        SZ_128K, //
+        SZ_1M,
     },
     transmute::{
         AsBytes,
@@ -728,8 +729,8 @@ unsafe impl AsBytes for MsgqRxHeader {}
 
 bitfield! {
     struct MsgHeaderVersion(u32) {
-        31:24 major as u8;
-        23:16 minor as u8;
+        31:24 major;
+        23:16 minor;
     }
 }
 
@@ -738,9 +739,9 @@ impl MsgHeaderVersion {
     const MINOR_TOT: u8 = 0;
 
     fn new() -> Self {
-        Self::default()
-            .set_major(Self::MAJOR_TOT)
-            .set_minor(Self::MINOR_TOT)
+        Self::zeroed()
+            .with_major(Self::MAJOR_TOT)
+            .with_minor(Self::MINOR_TOT)
     }
 }
 
diff --git a/drivers/gpu/nova-core/nova_core.rs b/drivers/gpu/nova-core/nova_core.rs
index 04a1fa6b25f8..3a0c45481a92 100644
--- a/drivers/gpu/nova-core/nova_core.rs
+++ b/drivers/gpu/nova-core/nova_core.rs
@@ -10,9 +10,6 @@
     InPlaceModule, //
 };
 
-#[macro_use]
-mod bitfield;
-
 mod driver;
 mod falcon;
 mod fb;

-- 
2.53.0