[PATCH v5 04/12] gpu: nova-core: add Chipset::name() method

Alexandre Courbot
2025-09-11T11:04:50Z

There are a few cases where we need the lowercase name of a given
chipset, notably to resolve firmware files paths for dynamic loading or
to build the module information.

So far, we relied on a static `NAMES` array for the latter, and some
CString hackery for the former.

Replace both with a new `name` const method that returns the lowercase
name of a chipset instance. We can generate it using the `paste!` macro.

Using this method removes the need to create a `CString` when loading
firmware, and lets us remove a couple of utility functions that now have
no user.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
---
drivers/gpu/nova-core/firmware.rs | 8 +++-----
drivers/gpu/nova-core/gpu.rs | 25 +++++++++++++++++--------
drivers/gpu/nova-core/util.rs | 20 --------------------
3 files changed, 20 insertions(+), 33 deletions(-)

diff --git a/drivers/gpu/nova-core/firmware.rs b/drivers/gpu/nova-core/firmware.rs
index 2931912ddba0ea1fe6d027ccec70b39cdb40344a..213d4506a53f83e7474861f6f81f033a9760fb61 100644
--- a/drivers/gpu/nova-core/firmware.rs
+++ b/drivers/gpu/nova-core/firmware.rs
@@ -30,9 +30,7 @@ pub(crate) struct Firmware {

impl Firmware {
pub(crate) fn new(dev: &device::Device, chipset: Chipset, ver: &str) -> Result<Firmware> {
- let mut chip_name = CString::try_from_fmt(fmt!("{chipset}"))?;
- chip_name.make_ascii_lowercase();
- let chip_name = &*chip_name;
+ let chip_name = chipset.name();

let request = |name_| {
CString::try_from_fmt(fmt!("nvidia/{chip_name}/gsp/{name_}-{ver}.bin"))
@@ -180,8 +178,8 @@ pub(crate) const fn create(
let mut this = Self(firmware::ModInfoBuilder::new(module_name));
let mut i = 0;

- while i < gpu::Chipset::NAMES.len() {
- this = this.make_entry_chipset(gpu::Chipset::NAMES[i]);
+ while i < gpu::Chipset::ALL.len() {
+ this = this.make_entry_chipset(gpu::Chipset::ALL[i].name());
i += 1;
}

diff --git a/drivers/gpu/nova-core/gpu.rs b/drivers/gpu/nova-core/gpu.rs
index 92fb0e4765ed322484672a1e01568216c3e0a7db..1dfd085189cbf188f9cfa829eb0cb7484d9c4d62 100644
--- a/drivers/gpu/nova-core/gpu.rs
+++ b/drivers/gpu/nova-core/gpu.rs
@@ -10,7 +10,6 @@
use crate::firmware::{Firmware, FIRMWARE_VERSION};
use crate::gfw;
use crate::regs;
-use crate::util;
use crate::vbios::Vbios;
use core::fmt;

@@ -28,13 +27,23 @@ impl Chipset {
$( Chipset::$variant, )*
];

- pub(crate) const NAMES: [&'static str; Self::ALL.len()] = [
- $( util::const_bytes_to_str(
- util::to_lowercase_bytes::<{ stringify!($variant).len() }>(
- stringify!($variant)
- ).as_slice()
- ), )*
- ];
+ ::kernel::macros::paste!(
+ /// Returns the name of this chipset, in lowercase.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// let chipset = Chipset::GA102;
+ /// assert_eq!(chipset.name(), "ga102");
+ /// ```
+ pub(crate) const fn name(&self) -> &'static str {
+ match *self {
+ $(
+ Chipset::$variant => stringify!([<$variant:lower>]),
+ )*
+ }
+ }
+ );
}

// TODO[FPRI]: replace with something like derive(FromPrimitive)
diff --git a/drivers/gpu/nova-core/util.rs b/drivers/gpu/nova-core/util.rs
index 76cedf3710d7bb248f62ed50381a70f8ffb3f19a..bf35f00cb732ee4fa6644854718a0ad99051666a 100644
--- a/drivers/gpu/nova-core/util.rs
+++ b/drivers/gpu/nova-core/util.rs
@@ -3,26 +3,6 @@
use kernel::prelude::*;
use kernel::time::{Delta, Instant, Monotonic};

-pub(crate) const fn to_lowercase_bytes<const N: usize>(s: &str) -> [u8; N] {
- let src = s.as_bytes();
- let mut dst = [0; N];
- let mut i = 0;
-
- while i < src.len() && i < N {
- dst[i] = (src[i] as char).to_ascii_lowercase() as u8;
- i += 1;
- }
-
- dst
-}
-
-pub(crate) const fn const_bytes_to_str(bytes: &[u8]) -> &str {
- match core::str::from_utf8(bytes) {
- Ok(string) => string,
- Err(_) => kernel::build_error!("Bytes are not valid UTF-8."),
- }
-}
-
/// Wait until `cond` is true or `timeout` elapsed.
///
/// When `cond` evaluates to `Some`, its return value is returned.

--
2.51.0