The SZ_* constants are usize, matching the CPU pointer width. But
device address spaces have their own widths (32-bit MMIO windows,
64-bit GPU framebuffers, etc.), so drivers end up casting these
constants with SZ_1M as u64 or helper functions. This adds
boilerplate with no safety benefit.
Add a SizeConstants trait with associated SZ_* constants, implemented
for u32, u64, and usize. With the trait in scope, callers write
u64::SZ_1M or u32::SZ_4K to get the constant in their device's
native width. All SZ_* values fit in a u32, so every implementation
is lossless. Each impl has a const assert to catch any future
constant that would overflow.
A define_sizes! macro generates everything from a single internal
list of names. The macro takes the target types as arguments, so
adding a new target type requires changing only the call site.
Suggested-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/all/DGB9G697GSWO.3VBFGU5MKFPMR@kernel.org/
Link: https://lore.kernel.org/all/DGHI8WRKBQS9.38910L6FIIZTE@kernel.org/
Reviewed-by: Eliot Courtney <ecourtney@nvidia.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Gary Guo <gary@garyguo.net>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Link: https://patch.msgid.link/20260404021204.339779-2-jhubbard@nvidia.com
[ Applied the "kernel vertical" imports style. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
nova-core will need to use SZ_1M, so make the remaining constants
available.
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/r/20250619-nova-frts-v6-5-ecf41ef99252@nvidia.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Add rust equivalent to include/linux/sizes.h, makes code more
readable. Only SZ_*K that QT2025 PHY driver uses are added.
Make generated constants accessible with a proper type.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
