Make EthernetMAC::new and EthernetDMA::new more safe

Author: datdenkikniet

CHANGELOG.md

@@ -2,6 +2,8 @@
 * General
     * Remove the `smi` feature and always enable miim/smi. Use `ieee802_3_miim` for SMI access
     * Split MAC and DMA setup into their own separate modules
+* CI
+    * Test compilability of examples more extensively
 * Examples:
     * Switch to `defmt` as logger
     * Use `probe-run` as runner

src/dma.rs

@@ -2,7 +2,7 @@ use cortex_m::peripheral::NVIC;
 
 use crate::{
     rx::{RxPacket, RxRing},
-    stm32::{Interrupt, ETHERNET_DMA},
+    stm32::{Interrupt, ETHERNET_DMA, ETHERNET_MAC},
     tx::TxRing,
     RxError, RxRingEntry, TxError, TxRingEntry,
 };
@@ -23,6 +23,11 @@ impl<'rx, 'tx> EthernetDMA<'rx, 'tx> {
     /// usually not accessible.
     pub(crate) fn new(
         eth_dma: ETHERNET_DMA,
+        // Take a reference to ETHERNET_MAC to ensure that
+        // this function cannot be called before `EthernetMAC::new`.
+        // If we do that, shenanigans ensues (presumably clock and wait
+        // condition mismatch)
+        #[allow(unused_variables)] eth_mac: &ETHERNET_MAC,
         rx_buffer: &'rx mut [RxRingEntry],
         tx_buffer: &'tx mut [TxRingEntry],
     ) -> Self {

src/lib.rs

@@ -124,10 +124,10 @@ where
     // Note: this _must_ happen before configuring the MAC.
     // It's not entirely clear why, but no interrupts are
     // generated if the order is reversed.
-    let dma = EthernetDMA::new(eth_dma, rx_buffer, tx_buffer);
+    let dma = EthernetDMA::new(eth_dma, &eth_mac, rx_buffer, tx_buffer);
 
     // Configure the ethernet MAC
-    let mac = EthernetMAC::new(eth_mac, eth_mmc, clocks)?;
+    let mac = EthernetMAC::new(eth_mac, eth_mmc, &dma, clocks)?;
 
     Ok((dma, mac))
 }
@@ -182,10 +182,10 @@ where
     // Note: this _must_ happen before configuring the MAC.
     // It's not entirely clear why, but no interrupts are
     // generated if the order is reversed.
-    let dma = EthernetDMA::new(eth_dma, rx_buffer, tx_buffer);
+    let dma = EthernetDMA::new(eth_dma, &eth_mac, rx_buffer, tx_buffer);
 
     // Configure the ethernet MAC
-    let mac = EthernetMAC::new(eth_mac, eth_mmc, clocks)?.with_mii(mdio, mdc);
+    let mac = EthernetMAC::new(eth_mac, eth_mmc, &dma, clocks)?.with_mii(mdio, mdc);
 
     Ok((dma, mac))
 }

src/mac/mod.rs

@@ -5,6 +5,7 @@ use core::ops::Deref;
 use crate::{
     hal::rcc::Clocks,
     stm32::{ETHERNET_MAC, ETHERNET_MMC},
+    EthernetDMA,
 };
 
 mod miim;
@@ -48,6 +49,10 @@ impl EthernetMAC {
     pub(crate) fn new(
         eth_mac: ETHERNET_MAC,
         eth_mmc: ETHERNET_MMC,
+        // Take a reference to EthernetDMA to ensure
+        // that `EthernetDMA` has been called before
+        // this function.
+        #[allow(unused)] eth_dma: &EthernetDMA,
         clocks: Clocks,
     ) -> Result<Self, WrongClock> {
         let clock_frequency = clocks.hclk().to_Hz();