Previously, bitstructs were hardcoded to use u32 as the underlying
storage type. Add support for different storage types (u8, u16, u32,
u64) to the bitstruct macro.
New syntax is: struct Name: <type ex., u32> { ... }
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
---
drivers/gpu/nova-core/bitstruct.rs | 71 ++++++++++++++++------------
drivers/gpu/nova-core/regs/macros.rs | 16 +++----
2 files changed, 48 insertions(+), 39 deletions(-)
diff --git a/drivers/gpu/nova-core/bitstruct.rs b/drivers/gpu/nova-core/bitstruct.rs
index 1dd9edab7d07..068334c86981 100644
--- a/drivers/gpu/nova-core/bitstruct.rs
+++ b/drivers/gpu/nova-core/bitstruct.rs
@@ -9,7 +9,7 @@
///
/// ```rust
/// bitstruct! {
-/// struct ControlReg {
+/// struct ControlReg: u32 {
/// 3:0 mode as u8 ?=> Mode;
/// 7:4 state as u8 => State;
/// }
@@ -34,21 +34,21 @@
/// and returns the result. This is useful with fields for which not all values are valid.
macro_rules! bitstruct {
// Main entry point - defines the bitfield struct with fields
- (struct $name:ident $(, $comment:literal)? { $($fields:tt)* }) => {
- bitstruct!(@core $name $(, $comment)? { $($fields)* });
+ (struct $name:ident : $storage:ty $(, $comment:literal)? { $($fields:tt)* }) => {
+ bitstruct!(@core $name $storage $(, $comment)? { $($fields)* });
};
// All rules below are helpers.
// Defines the wrapper `$name` type, as well as its relevant implementations (`Debug`,
// `Default`, `BitOr`, and conversion to the value type) and field accessor methods.
- (@core $name:ident $(, $comment:literal)? { $($fields:tt)* }) => {
+ (@core $name:ident $storage:ty $(, $comment:literal)? { $($fields:tt)* }) => {
$(
#[doc=$comment]
)?
#[repr(transparent)]
#[derive(Clone, Copy)]
- pub(crate) struct $name(u32);
+ pub(crate) struct $name($storage);
impl ::core::ops::BitOr for $name {
type Output = Self;
@@ -58,20 +58,20 @@ fn bitor(self, rhs: Self) -> Self::Output {
}
}
- impl ::core::convert::From<$name> for u32 {
- fn from(val: $name) -> u32 {
+ impl ::core::convert::From<$name> for $storage {
+ fn from(val: $name) -> $storage {
val.0
}
}
- bitstruct!(@fields_dispatcher $name { $($fields)* });
+ bitstruct!(@fields_dispatcher $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 $name:ident {
+ (@fields_dispatcher $name:ident $storage:ty {
$($hi:tt:$lo:tt $field:ident as $type:tt
$(?=> $try_into_type:ty)?
$(=> $into_type:ty)?
@@ -80,7 +80,7 @@ fn from(val: $name) -> u32 {
)*
}
) => {
- bitstruct!(@field_accessors $name {
+ bitstruct!(@field_accessors $name $storage {
$(
$hi:$lo $field as $type
$(?=> $try_into_type)?
@@ -89,13 +89,13 @@ fn from(val: $name) -> u32 {
;
)*
});
- bitstruct!(@debug $name { $($field;)* });
- bitstruct!(@default $name { $($field;)* });
+ bitstruct!(@debug $name $storage { $($field;)* });
+ bitstruct!(@default $name $storage { $($field;)* });
};
// Defines all the field getter/setter methods for `$name`.
(
- @field_accessors $name:ident {
+ @field_accessors $name:ident $storage:ty {
$($hi:tt:$lo:tt $field:ident as $type:tt
$(?=> $try_into_type:ty)?
$(=> $into_type:ty)?
@@ -111,7 +111,7 @@ fn from(val: $name) -> u32 {
#[allow(dead_code)]
impl $name {
$(
- bitstruct!(@field_accessor $name $hi:$lo $field as $type
+ bitstruct!(@field_accessor $name $storage, $hi:$lo $field as $type
$(?=> $try_into_type)?
$(=> $into_type)?
$(, $comment)?
@@ -145,11 +145,11 @@ impl $name {
// Catches fields defined as `bool` and convert them into a boolean value.
(
- @field_accessor $name:ident $hi:tt:$lo:tt $field:ident as bool => $into_type:ty
+ @field_accessor $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident as bool => $into_type:ty
$(, $comment:literal)?;
) => {
bitstruct!(
- @leaf_accessor $name $hi:$lo $field
+ @leaf_accessor $name $storage, $hi:$lo $field
{ |f| <$into_type>::from(if f != 0 { true } else { false }) }
$into_type => $into_type $(, $comment)?;
);
@@ -157,17 +157,17 @@ impl $name {
// Shortcut for fields defined as `bool` without the `=>` syntax.
(
- @field_accessor $name:ident $hi:tt:$lo:tt $field:ident as bool $(, $comment:literal)?;
+ @field_accessor $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident as bool $(, $comment:literal)?;
) => {
- bitstruct!(@field_accessor $name $hi:$lo $field as bool => bool $(, $comment)?;);
+ bitstruct!(@field_accessor $name $storage, $hi:$lo $field as bool => bool $(, $comment)?;);
};
// Catches the `?=>` syntax for non-boolean fields.
(
- @field_accessor $name:ident $hi:tt:$lo:tt $field:ident as $type:tt ?=> $try_into_type:ty
+ @field_accessor $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident as $type:tt ?=> $try_into_type:ty
$(, $comment:literal)?;
) => {
- bitstruct!(@leaf_accessor $name $hi:$lo $field
+ bitstruct!(@leaf_accessor $name $storage, $hi:$lo $field
{ |f| <$try_into_type>::try_from(f as $type) } $try_into_type =>
::core::result::Result<
$try_into_type,
@@ -178,29 +178,38 @@ impl $name {
// Catches the `=>` syntax for non-boolean fields.
(
- @field_accessor $name:ident $hi:tt:$lo:tt $field:ident as $type:tt => $into_type:ty
+ @field_accessor $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident as $type:tt => $into_type:ty
$(, $comment:literal)?;
) => {
- bitstruct!(@leaf_accessor $name $hi:$lo $field
+ bitstruct!(@leaf_accessor $name $storage, $hi:$lo $field
{ |f| <$into_type>::from(f as $type) } $into_type => $into_type $(, $comment)?;);
};
// Shortcut for non-boolean fields defined without the `=>` or `?=>` syntax.
(
- @field_accessor $name:ident $hi:tt:$lo:tt $field:ident as $type:tt
+ @field_accessor $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident as $type:tt
$(, $comment:literal)?;
) => {
- bitstruct!(@field_accessor $name $hi:$lo $field as $type => $type $(, $comment)?;);
+ bitstruct!(@field_accessor $name $storage, $hi:$lo $field as $type => $type $(, $comment)?;);
};
// Generates the accessor methods for a single field.
(
- @leaf_accessor $name:ident $hi:tt:$lo:tt $field:ident
+ @leaf_accessor $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident
{ $process:expr } $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>]: u32 = ((((1 << $hi) - 1) << 1) + 1) - ((1 << $lo) - 1);
+ const [<$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 $storage,
+ _ => <$storage>::MAX
+ }
+ };
const [<$field:upper _SHIFT>]: u32 = Self::[<$field:upper _MASK>].trailing_zeros();
);
@@ -211,7 +220,7 @@ impl $name {
#[inline(always)]
pub(crate) fn $field(self) -> $res_type {
::kernel::macros::paste!(
- const MASK: u32 = $name::[<$field:upper _MASK>];
+ const MASK: $storage = $name::[<$field:upper _MASK>];
const SHIFT: u32 = $name::[<$field:upper _SHIFT>];
);
let field = ((self.0 & MASK) >> SHIFT);
@@ -226,9 +235,9 @@ pub(crate) fn $field(self) -> $res_type {
)?
#[inline(always)]
pub(crate) fn [<set_ $field>](mut self, value: $to_type) -> Self {
- const MASK: u32 = $name::[<$field:upper _MASK>];
+ const MASK: $storage = $name::[<$field:upper _MASK>];
const SHIFT: u32 = $name::[<$field:upper _SHIFT>];
- let value = (u32::from(value) << SHIFT) & MASK;
+ let value = (<$storage>::from(value) << SHIFT) & MASK;
self.0 = (self.0 & !MASK) | value;
self
@@ -237,7 +246,7 @@ pub(crate) fn [<set_ $field>](mut self, value: $to_type) -> Self {
};
// Generates the `Debug` implementation for `$name`.
- (@debug $name:ident { $($field:ident;)* }) => {
+ (@debug $name:ident $storage:ty { $($field:ident;)* }) => {
impl ::core::fmt::Debug for $name {
fn fmt(&self, f: &mut ::core::fmt::Formatter<'_>) -> ::core::fmt::Result {
f.debug_struct(stringify!($name))
@@ -251,7 +260,7 @@ fn fmt(&self, f: &mut ::core::fmt::Formatter<'_>) -> ::core::fmt::Result {
};
// Generates the `Default` implementation for `$name`.
- (@default $name:ident { $($field:ident;)* }) => {
+ (@default $name:ident $storage:ty { $($field:ident;)* }) => {
/// Returns a value for the bitstruct where all fields are set to their default value.
impl ::core::default::Default for $name {
fn default() -> Self {
diff --git a/drivers/gpu/nova-core/regs/macros.rs b/drivers/gpu/nova-core/regs/macros.rs
index 3fb6852dff04..bbfeab147c9f 100644
--- a/drivers/gpu/nova-core/regs/macros.rs
+++ b/drivers/gpu/nova-core/regs/macros.rs
@@ -284,25 +284,25 @@ pub(crate) trait RegisterBase<T> {
macro_rules! register {
// Creates a register at a fixed offset of the MMIO space.
($name:ident @ $offset:literal $(, $comment:literal)? { $($fields:tt)* } ) => {
- bitstruct!(struct $name $(, $comment)? { $($fields)* } );
+ bitstruct!(struct $name: u32 $(, $comment)? { $($fields)* } );
register!(@io_fixed $name @ $offset);
};
// Creates an alias register of fixed offset register `alias` with its own fields.
($name:ident => $alias:ident $(, $comment:literal)? { $($fields:tt)* } ) => {
- bitstruct!(struct $name $(, $comment)? { $($fields)* } );
+ bitstruct!(struct $name: u32 $(, $comment)? { $($fields)* } );
register!(@io_fixed $name @ $alias::OFFSET);
};
// Creates a register at a relative offset from a base address provider.
($name:ident @ $base:ty [ $offset:literal ] $(, $comment:literal)? { $($fields:tt)* } ) => {
- bitstruct!(struct $name $(, $comment)? { $($fields)* } );
+ bitstruct!(struct $name: u32 $(, $comment)? { $($fields)* } );
register!(@io_relative $name @ $base [ $offset ]);
};
// Creates an alias register of relative offset register `alias` with its own fields.
($name:ident => $base:ty [ $alias:ident ] $(, $comment:literal)? { $($fields:tt)* }) => {
- bitstruct!(struct $name $(, $comment)? { $($fields)* } );
+ bitstruct!(struct $name: u32 $(, $comment)? { $($fields)* } );
register!(@io_relative $name @ $base [ $alias::OFFSET ]);
};
@@ -313,7 +313,7 @@ macro_rules! register {
}
) => {
static_assert!(::core::mem::size_of::<u32>() <= $stride);
- bitstruct!(struct $name $(, $comment)? { $($fields)* } );
+ bitstruct!(struct $name: u32 $(, $comment)? { $($fields)* } );
register!(@io_array $name @ $offset [ $size ; $stride ]);
};
@@ -334,7 +334,7 @@ macro_rules! register {
$(, $comment:literal)? { $($fields:tt)* }
) => {
static_assert!(::core::mem::size_of::<u32>() <= $stride);
- bitstruct!(struct $name $(, $comment)? { $($fields)* } );
+ bitstruct!(struct $name: u32 $(, $comment)? { $($fields)* } );
register!(@io_relative_array $name @ $base [ $offset [ $size ; $stride ] ]);
};
@@ -356,7 +356,7 @@ macro_rules! register {
}
) => {
static_assert!($idx < $alias::SIZE);
- bitstruct!(struct $name $(, $comment)? { $($fields)* } );
+ bitstruct!(struct $name: u32 $(, $comment)? { $($fields)* } );
register!(@io_relative $name @ $base [ $alias::OFFSET + $idx * $alias::STRIDE ] );
};
@@ -365,7 +365,7 @@ macro_rules! register {
// to avoid it being interpreted in place of the relative register array alias rule.
($name:ident => $alias:ident [ $idx:expr ] $(, $comment:literal)? { $($fields:tt)* }) => {
static_assert!($idx < $alias::SIZE);
- bitstruct!(struct $name $(, $comment)? { $($fields)* } );
+ bitstruct!(struct $name: u32 $(, $comment)? { $($fields)* } );
register!(@io_fixed $name @ $alias::OFFSET + $idx * $alias::STRIDE );
};
--
2.34.1On Thu Sep 4, 2025 at 6:54 AM JST, Joel Fernandes wrote:
> Previously, bitstructs were hardcoded to use u32 as the underlying
> storage type. Add support for different storage types (u8, u16, u32,
> u64) to the bitstruct macro.
>
> New syntax is: struct Name: <type ex., u32> { ... }
>
> Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
<snip>
> // Generates the accessor methods for a single field.
> (
> - @leaf_accessor $name:ident $hi:tt:$lo:tt $field:ident
> + @leaf_accessor $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident
> { $process:expr } $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>]: u32 = ((((1 << $hi) - 1) << 1) + 1) - ((1 << $lo) - 1);
> + const [<$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 $storage,
> + _ => <$storage>::MAX
Since this is a const expression, you can use `build_error!` to make
compilation fail in the unlikely event the `_` is taken due to bug in
the code.
> + }
> + };
> const [<$field:upper _SHIFT>]: u32 = Self::[<$field:upper _MASK>].trailing_zeros();
> );
>
> @@ -211,7 +220,7 @@ impl $name {
> #[inline(always)]
> pub(crate) fn $field(self) -> $res_type {
> ::kernel::macros::paste!(
> - const MASK: u32 = $name::[<$field:upper _MASK>];
> + const MASK: $storage = $name::[<$field:upper _MASK>];
> const SHIFT: u32 = $name::[<$field:upper _SHIFT>];
> );
> let field = ((self.0 & MASK) >> SHIFT);
> @@ -226,9 +235,9 @@ pub(crate) fn $field(self) -> $res_type {
> )?
> #[inline(always)]
> pub(crate) fn [<set_ $field>](mut self, value: $to_type) -> Self {
> - const MASK: u32 = $name::[<$field:upper _MASK>];
> + const MASK: $storage = $name::[<$field:upper _MASK>];
> const SHIFT: u32 = $name::[<$field:upper _SHIFT>];
> - let value = (u32::from(value) << SHIFT) & MASK;
> + let value = (<$storage>::from(value) << SHIFT) & MASK;
> self.0 = (self.0 & !MASK) | value;
>
> self
> @@ -237,7 +246,7 @@ pub(crate) fn [<set_ $field>](mut self, value: $to_type) -> Self {
> };
>
> // Generates the `Debug` implementation for `$name`.
> - (@debug $name:ident { $($field:ident;)* }) => {
> + (@debug $name:ident $storage:ty { $($field:ident;)* }) => {
This rule doesn't make use of the `$storage` argument.
> impl ::core::fmt::Debug for $name {
> fn fmt(&self, f: &mut ::core::fmt::Formatter<'_>) -> ::core::fmt::Result {
> f.debug_struct(stringify!($name))
> @@ -251,7 +260,7 @@ fn fmt(&self, f: &mut ::core::fmt::Formatter<'_>) -> ::core::fmt::Result {
> };
>
> // Generates the `Default` implementation for `$name`.
> - (@default $name:ident { $($field:ident;)* }) => {
> + (@default $name:ident $storage:ty { $($field:ident;)* }) => {
Neither does this one.
On Mon, Sep 08, 2025 at 12:26:43PM +0900, Alexandre Courbot wrote:
> On Thu Sep 4, 2025 at 6:54 AM JST, Joel Fernandes wrote:
> > Previously, bitstructs were hardcoded to use u32 as the underlying
> > storage type. Add support for different storage types (u8, u16, u32,
> > u64) to the bitstruct macro.
> >
> > New syntax is: struct Name: <type ex., u32> { ... }
> >
> > Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
> <snip>
> > // Generates the accessor methods for a single field.
> > (
> > - @leaf_accessor $name:ident $hi:tt:$lo:tt $field:ident
> > + @leaf_accessor $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident
> > { $process:expr } $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>]: u32 = ((((1 << $hi) - 1) << 1) + 1) - ((1 << $lo) - 1);
> > + const [<$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 $storage,
> > + _ => <$storage>::MAX
>
> Since this is a const expression, you can use `build_error!` to make
> compilation fail in the unlikely event the `_` is taken due to bug in
> the code.
Makes sense, changed.
>
> > + }
> > + };
> > const [<$field:upper _SHIFT>]: u32 = Self::[<$field:upper _MASK>].trailing_zeros();
> > );
> >
> > @@ -211,7 +220,7 @@ impl $name {
> > #[inline(always)]
> > pub(crate) fn $field(self) -> $res_type {
> > ::kernel::macros::paste!(
> > - const MASK: u32 = $name::[<$field:upper _MASK>];
> > + const MASK: $storage = $name::[<$field:upper _MASK>];
> > const SHIFT: u32 = $name::[<$field:upper _SHIFT>];
> > );
> > let field = ((self.0 & MASK) >> SHIFT);
> > @@ -226,9 +235,9 @@ pub(crate) fn $field(self) -> $res_type {
> > )?
> > #[inline(always)]
> > pub(crate) fn [<set_ $field>](mut self, value: $to_type) -> Self {
> > - const MASK: u32 = $name::[<$field:upper _MASK>];
> > + const MASK: $storage = $name::[<$field:upper _MASK>];
> > const SHIFT: u32 = $name::[<$field:upper _SHIFT>];
> > - let value = (u32::from(value) << SHIFT) & MASK;
> > + let value = (<$storage>::from(value) << SHIFT) & MASK;
> > self.0 = (self.0 & !MASK) | value;
> >
> > self
> > @@ -237,7 +246,7 @@ pub(crate) fn [<set_ $field>](mut self, value: $to_type) -> Self {
> > };
> >
> > // Generates the `Debug` implementation for `$name`.
> > - (@debug $name:ident { $($field:ident;)* }) => {
> > + (@debug $name:ident $storage:ty { $($field:ident;)* }) => {
>
> This rule doesn't make use of the `$storage` argument.
Removed unused arg, thanks.
> > impl ::core::fmt::Debug for $name {
> > fn fmt(&self, f: &mut ::core::fmt::Formatter<'_>) -> ::core::fmt::Result {
> > f.debug_struct(stringify!($name))
> > @@ -251,7 +260,7 @@ fn fmt(&self, f: &mut ::core::fmt::Formatter<'_>) -> ::core::fmt::Result {
> > };
> >
> > // Generates the `Default` implementation for `$name`.
> > - (@default $name:ident { $($field:ident;)* }) => {
> > + (@default $name:ident $storage:ty { $($field:ident;)* }) => {
>
> Neither does this one.
Removed unused arg, thanks.
thanks,
- Joel
On Wed, Sep 03, 2025 at 05:54:26PM -0400, Joel Fernandes wrote:
> Previously, bitstructs were hardcoded to use u32 as the underlying
> storage type. Add support for different storage types (u8, u16, u32,
> u64) to the bitstruct macro.
>
> New syntax is: struct Name: <type ex., u32> { ... }
>
> Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
> ---
> drivers/gpu/nova-core/bitstruct.rs | 71 ++++++++++++++++------------
> drivers/gpu/nova-core/regs/macros.rs | 16 +++----
> 2 files changed, 48 insertions(+), 39 deletions(-)
>
> diff --git a/drivers/gpu/nova-core/bitstruct.rs b/drivers/gpu/nova-core/bitstruct.rs
> index 1dd9edab7d07..068334c86981 100644
> --- a/drivers/gpu/nova-core/bitstruct.rs
> +++ b/drivers/gpu/nova-core/bitstruct.rs
> @@ -9,7 +9,7 @@
> ///
> /// ```rust
> /// bitstruct! {
> -/// struct ControlReg {
> +/// struct ControlReg: u32 {
> /// 3:0 mode as u8 ?=> Mode;
> /// 7:4 state as u8 => State;
> /// }
> @@ -34,21 +34,21 @@
> /// and returns the result. This is useful with fields for which not all values are valid.
> macro_rules! bitstruct {
> // Main entry point - defines the bitfield struct with fields
> - (struct $name:ident $(, $comment:literal)? { $($fields:tt)* }) => {
> - bitstruct!(@core $name $(, $comment)? { $($fields)* });
> + (struct $name:ident : $storage:ty $(, $comment:literal)? { $($fields:tt)* }) => {
> + bitstruct!(@core $name $storage $(, $comment)? { $($fields)* });
> };
>
> // All rules below are helpers.
>
> // Defines the wrapper `$name` type, as well as its relevant implementations (`Debug`,
> // `Default`, `BitOr`, and conversion to the value type) and field accessor methods.
> - (@core $name:ident $(, $comment:literal)? { $($fields:tt)* }) => {
> + (@core $name:ident $storage:ty $(, $comment:literal)? { $($fields:tt)* }) => {
> $(
> #[doc=$comment]
> )?
> #[repr(transparent)]
> #[derive(Clone, Copy)]
> - pub(crate) struct $name(u32);
> + pub(crate) struct $name($storage);
>
> impl ::core::ops::BitOr for $name {
> type Output = Self;
> @@ -58,20 +58,20 @@ fn bitor(self, rhs: Self) -> Self::Output {
> }
> }
>
> - impl ::core::convert::From<$name> for u32 {
> - fn from(val: $name) -> u32 {
> + impl ::core::convert::From<$name> for $storage {
> + fn from(val: $name) -> $storage {
> val.0
> }
> }
>
> - bitstruct!(@fields_dispatcher $name { $($fields)* });
> + bitstruct!(@fields_dispatcher $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 $name:ident {
> + (@fields_dispatcher $name:ident $storage:ty {
> $($hi:tt:$lo:tt $field:ident as $type:tt
> $(?=> $try_into_type:ty)?
> $(=> $into_type:ty)?
> @@ -80,7 +80,7 @@ fn from(val: $name) -> u32 {
> )*
> }
> ) => {
> - bitstruct!(@field_accessors $name {
> + bitstruct!(@field_accessors $name $storage {
> $(
> $hi:$lo $field as $type
> $(?=> $try_into_type)?
> @@ -89,13 +89,13 @@ fn from(val: $name) -> u32 {
> ;
> )*
> });
> - bitstruct!(@debug $name { $($field;)* });
> - bitstruct!(@default $name { $($field;)* });
> + bitstruct!(@debug $name $storage { $($field;)* });
> + bitstruct!(@default $name $storage { $($field;)* });
> };
>
> // Defines all the field getter/setter methods for `$name`.
> (
> - @field_accessors $name:ident {
> + @field_accessors $name:ident $storage:ty {
> $($hi:tt:$lo:tt $field:ident as $type:tt
> $(?=> $try_into_type:ty)?
> $(=> $into_type:ty)?
> @@ -111,7 +111,7 @@ fn from(val: $name) -> u32 {
> #[allow(dead_code)]
> impl $name {
> $(
> - bitstruct!(@field_accessor $name $hi:$lo $field as $type
> + bitstruct!(@field_accessor $name $storage, $hi:$lo $field as $type
> $(?=> $try_into_type)?
> $(=> $into_type)?
> $(, $comment)?
> @@ -145,11 +145,11 @@ impl $name {
>
> // Catches fields defined as `bool` and convert them into a boolean value.
> (
> - @field_accessor $name:ident $hi:tt:$lo:tt $field:ident as bool => $into_type:ty
> + @field_accessor $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident as bool => $into_type:ty
> $(, $comment:literal)?;
> ) => {
> bitstruct!(
> - @leaf_accessor $name $hi:$lo $field
> + @leaf_accessor $name $storage, $hi:$lo $field
> { |f| <$into_type>::from(if f != 0 { true } else { false }) }
> $into_type => $into_type $(, $comment)?;
> );
> @@ -157,17 +157,17 @@ impl $name {
>
> // Shortcut for fields defined as `bool` without the `=>` syntax.
> (
> - @field_accessor $name:ident $hi:tt:$lo:tt $field:ident as bool $(, $comment:literal)?;
> + @field_accessor $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident as bool $(, $comment:literal)?;
> ) => {
> - bitstruct!(@field_accessor $name $hi:$lo $field as bool => bool $(, $comment)?;);
> + bitstruct!(@field_accessor $name $storage, $hi:$lo $field as bool => bool $(, $comment)?;);
> };
>
> // Catches the `?=>` syntax for non-boolean fields.
> (
> - @field_accessor $name:ident $hi:tt:$lo:tt $field:ident as $type:tt ?=> $try_into_type:ty
> + @field_accessor $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident as $type:tt ?=> $try_into_type:ty
> $(, $comment:literal)?;
> ) => {
> - bitstruct!(@leaf_accessor $name $hi:$lo $field
> + bitstruct!(@leaf_accessor $name $storage, $hi:$lo $field
> { |f| <$try_into_type>::try_from(f as $type) } $try_into_type =>
> ::core::result::Result<
> $try_into_type,
> @@ -178,29 +178,38 @@ impl $name {
>
> // Catches the `=>` syntax for non-boolean fields.
> (
> - @field_accessor $name:ident $hi:tt:$lo:tt $field:ident as $type:tt => $into_type:ty
> + @field_accessor $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident as $type:tt => $into_type:ty
> $(, $comment:literal)?;
> ) => {
> - bitstruct!(@leaf_accessor $name $hi:$lo $field
> + bitstruct!(@leaf_accessor $name $storage, $hi:$lo $field
> { |f| <$into_type>::from(f as $type) } $into_type => $into_type $(, $comment)?;);
> };
>
> // Shortcut for non-boolean fields defined without the `=>` or `?=>` syntax.
> (
> - @field_accessor $name:ident $hi:tt:$lo:tt $field:ident as $type:tt
> + @field_accessor $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident as $type:tt
> $(, $comment:literal)?;
> ) => {
> - bitstruct!(@field_accessor $name $hi:$lo $field as $type => $type $(, $comment)?;);
> + bitstruct!(@field_accessor $name $storage, $hi:$lo $field as $type => $type $(, $comment)?;);
> };
>
> // Generates the accessor methods for a single field.
> (
> - @leaf_accessor $name:ident $hi:tt:$lo:tt $field:ident
> + @leaf_accessor $name:ident $storage:ty, $hi:tt:$lo:tt $field:ident
> { $process:expr } $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>]: u32 = ((((1 << $hi) - 1) << 1) + 1) - ((1 << $lo) - 1);
> + const [<$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 $storage,
Not really important for current users, but something to think about for
the future is fields that are represented using byte arrays (e.g. a
`u24` represented as `[u8; 3]`).
I think your approach here could be fairly easily modified to handle
those use-cases, just something to think about.
For the byte array storage types, you would also need to think about
endianness (MSB v. LSB).
> + _ => <$storage>::MAX
> + }
> + };
> const [<$field:upper _SHIFT>]: u32 = Self::[<$field:upper _MASK>].trailing_zeros();
> );
>
> @@ -211,7 +220,7 @@ impl $name {
> #[inline(always)]
> pub(crate) fn $field(self) -> $res_type {
> ::kernel::macros::paste!(
> - const MASK: u32 = $name::[<$field:upper _MASK>];
> + const MASK: $storage = $name::[<$field:upper _MASK>];
> const SHIFT: u32 = $name::[<$field:upper _SHIFT>];
> );
> let field = ((self.0 & MASK) >> SHIFT);
> @@ -226,9 +235,9 @@ pub(crate) fn $field(self) -> $res_type {
> )?
> #[inline(always)]
> pub(crate) fn [<set_ $field>](mut self, value: $to_type) -> Self {
> - const MASK: u32 = $name::[<$field:upper _MASK>];
> + const MASK: $storage = $name::[<$field:upper _MASK>];
> const SHIFT: u32 = $name::[<$field:upper _SHIFT>];
> - let value = (u32::from(value) << SHIFT) & MASK;
> + let value = (<$storage>::from(value) << SHIFT) & MASK;
> self.0 = (self.0 & !MASK) | value;
>
> self
> @@ -237,7 +246,7 @@ pub(crate) fn [<set_ $field>](mut self, value: $to_type) -> Self {
> };
>
> // Generates the `Debug` implementation for `$name`.
> - (@debug $name:ident { $($field:ident;)* }) => {
> + (@debug $name:ident $storage:ty { $($field:ident;)* }) => {
> impl ::core::fmt::Debug for $name {
> fn fmt(&self, f: &mut ::core::fmt::Formatter<'_>) -> ::core::fmt::Result {
> f.debug_struct(stringify!($name))
> @@ -251,7 +260,7 @@ fn fmt(&self, f: &mut ::core::fmt::Formatter<'_>) -> ::core::fmt::Result {
> };
>
> // Generates the `Default` implementation for `$name`.
> - (@default $name:ident { $($field:ident;)* }) => {
> + (@default $name:ident $storage:ty { $($field:ident;)* }) => {
> /// Returns a value for the bitstruct where all fields are set to their default value.
> impl ::core::default::Default for $name {
> fn default() -> Self {
> diff --git a/drivers/gpu/nova-core/regs/macros.rs b/drivers/gpu/nova-core/regs/macros.rs
> index 3fb6852dff04..bbfeab147c9f 100644
> --- a/drivers/gpu/nova-core/regs/macros.rs
> +++ b/drivers/gpu/nova-core/regs/macros.rs
> @@ -284,25 +284,25 @@ pub(crate) trait RegisterBase<T> {
> macro_rules! register {
> // Creates a register at a fixed offset of the MMIO space.
> ($name:ident @ $offset:literal $(, $comment:literal)? { $($fields:tt)* } ) => {
> - bitstruct!(struct $name $(, $comment)? { $($fields)* } );
> + bitstruct!(struct $name: u32 $(, $comment)? { $($fields)* } );
> register!(@io_fixed $name @ $offset);
> };
>
> // Creates an alias register of fixed offset register `alias` with its own fields.
> ($name:ident => $alias:ident $(, $comment:literal)? { $($fields:tt)* } ) => {
> - bitstruct!(struct $name $(, $comment)? { $($fields)* } );
> + bitstruct!(struct $name: u32 $(, $comment)? { $($fields)* } );
> register!(@io_fixed $name @ $alias::OFFSET);
> };
>
> // Creates a register at a relative offset from a base address provider.
> ($name:ident @ $base:ty [ $offset:literal ] $(, $comment:literal)? { $($fields:tt)* } ) => {
> - bitstruct!(struct $name $(, $comment)? { $($fields)* } );
> + bitstruct!(struct $name: u32 $(, $comment)? { $($fields)* } );
> register!(@io_relative $name @ $base [ $offset ]);
> };
>
> // Creates an alias register of relative offset register `alias` with its own fields.
> ($name:ident => $base:ty [ $alias:ident ] $(, $comment:literal)? { $($fields:tt)* }) => {
> - bitstruct!(struct $name $(, $comment)? { $($fields)* } );
> + bitstruct!(struct $name: u32 $(, $comment)? { $($fields)* } );
> register!(@io_relative $name @ $base [ $alias::OFFSET ]);
> };
>
> @@ -313,7 +313,7 @@ macro_rules! register {
> }
> ) => {
> static_assert!(::core::mem::size_of::<u32>() <= $stride);
> - bitstruct!(struct $name $(, $comment)? { $($fields)* } );
> + bitstruct!(struct $name: u32 $(, $comment)? { $($fields)* } );
> register!(@io_array $name @ $offset [ $size ; $stride ]);
> };
>
> @@ -334,7 +334,7 @@ macro_rules! register {
> $(, $comment:literal)? { $($fields:tt)* }
> ) => {
> static_assert!(::core::mem::size_of::<u32>() <= $stride);
> - bitstruct!(struct $name $(, $comment)? { $($fields)* } );
> + bitstruct!(struct $name: u32 $(, $comment)? { $($fields)* } );
> register!(@io_relative_array $name @ $base [ $offset [ $size ; $stride ] ]);
> };
>
> @@ -356,7 +356,7 @@ macro_rules! register {
> }
> ) => {
> static_assert!($idx < $alias::SIZE);
> - bitstruct!(struct $name $(, $comment)? { $($fields)* } );
> + bitstruct!(struct $name: u32 $(, $comment)? { $($fields)* } );
> register!(@io_relative $name @ $base [ $alias::OFFSET + $idx * $alias::STRIDE ] );
> };
>
> @@ -365,7 +365,7 @@ macro_rules! register {
> // to avoid it being interpreted in place of the relative register array alias rule.
> ($name:ident => $alias:ident [ $idx:expr ] $(, $comment:literal)? { $($fields:tt)* }) => {
> static_assert!($idx < $alias::SIZE);
> - bitstruct!(struct $name $(, $comment)? { $($fields)* } );
> + bitstruct!(struct $name: u32 $(, $comment)? { $($fields)* } );
> register!(@io_fixed $name @ $alias::OFFSET + $idx * $alias::STRIDE );
> };
>
> --
> 2.34.1
>
>
Reviewed-by: Elle Rhumsaa <elle@weathered-steel.dev>
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