eth: warn on tx ring overflow

libboard_zynq/src/eth/tx.rs

@@ -2,6 +2,7 @@ use core::ops::{Deref, DerefMut};
 use alloc::{vec, vec::Vec};
 use libcortex_a9::{cache::dcc_slice, UncachedSlice};
 use libregister::*;
+use log::warn;
 use super::{Buffer, regs};
 
 /// Descriptor entry
@@ -109,6 +110,7 @@ impl DescList {
             Some(PktRef { entry, buffer, regs })
         } else {
             // Still in use by HW (sending too fast, ring exceeded)
+            warn!("tx ring overflow");
             None
         }
     }