1 files changed, 47 insertions, 0 deletions
diff --git a/drivers/gpu/nova-core/util.rs b/drivers/gpu/nova-core/util.rs
new file mode 100644
index 000000000000..76cedf3710d7
--- /dev/null
+++ b/drivers/gpu/nova-core/util.rs
@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: GPL-2.0
+
+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.
+///
+/// `Err(ETIMEDOUT)` is returned if `timeout` has been reached without `cond` evaluating to
+/// `Some`.
+///
+/// TODO[DLAY]: replace with `read_poll_timeout` once it is available.
+/// (https://lore.kernel.org/lkml/20250220070611.214262-8-fujita.tomonori@gmail.com/)
+pub(crate) fn wait_on<R, F: Fn() -> Option<R>>(timeout: Delta, cond: F) -> Result<R> {
+    let start_time = Instant::<Monotonic>::now();
+
+    loop {
+        if let Some(ret) = cond() {
+            return Ok(ret);
+        }
+
+        if start_time.elapsed().as_nanos() > timeout.as_nanos() {
+            return Err(ETIMEDOUT);
+        }
+    }
+}