[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20250903215428.1296517-3-joelagnelf@nvidia.com>
Date: Wed, 3 Sep 2025 17:54:26 -0400
From: Joel Fernandes <joelagnelf@...dia.com>
To: linux-kernel@...r.kernel.org,
dri-devel@...ts.freedesktop.org,
dakr@...nel.org,
acourbot@...dia.com
Cc: Alistair Popple <apopple@...dia.com>,
Miguel Ojeda <ojeda@...nel.org>,
Alex Gaynor <alex.gaynor@...il.com>,
Boqun Feng <boqun.feng@...il.com>,
Gary Guo <gary@...yguo.net>,
bjorn3_gh@...tonmail.com,
Benno Lossin <lossin@...nel.org>,
Andreas Hindborg <a.hindborg@...nel.org>,
Alice Ryhl <aliceryhl@...gle.com>,
Trevor Gross <tmgross@...ch.edu>,
David Airlie <airlied@...il.com>,
Simona Vetter <simona@...ll.ch>,
Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
Maxime Ripard <mripard@...nel.org>,
Thomas Zimmermann <tzimmermann@...e.de>,
John Hubbard <jhubbard@...dia.com>,
Joel Fernandes <joelagnelf@...dia.com>,
Timur Tabi <ttabi@...dia.com>,
joel@...lfernandes.org,
Elle Rhumsaa <elle@...thered-steel.dev>,
Daniel Almeida <daniel.almeida@...labora.com>,
nouveau@...ts.freedesktop.org,
rust-for-linux@...r.kernel.org
Subject: [PATCH v2 2/4] nova-core: bitstruct: Add support for different storage widths
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@...dia.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 );
};
--
2.34.1
Powered by blists - more mailing lists