Merge #248 #249

248: Make more CRC methods const r=richardeoin a=AlyoshaVasilieva

The only one that has any significant effect is Config's `reflect` since it's now usable when you're making a const Config.

249: Ethernet: Disable RA in filtering, fix MAC address setting r=richardeoin a=adamgreig

The MACA0LR/HR registers hold the address the MAC can use for filtering received packets, but they're only loaded into the MAC core when LR is written to. Currently the ethernet driver writes to LR first and then HR, so the MAC core doesn't get the bits from HR, which breaks filtering. I believe that's why the RA (receive-all) bit has been set, which bypasses the filtering.

This PR fixes writing the MAC address and disables the no-longer-required RA bit.

I've tested this with an H745 nucleo board and the ethernet-rtic-stm32h747i-disco example, changing just the GPIO setup to match the Nucleo.

See also embassy-rs/embassy#389.

Co-authored-by: Malloc Voidstar <1284317+AlyoshaVasilieva@users.noreply.github.com>
Co-authored-by: Adam Greig <adam@adamgreig.com>

Author: 3 people

src/crc.rs

@@ -210,7 +210,7 @@ impl Polynomial {
     }
 
     /// Return POLYSIZE register value.
-    fn polysize(self) -> u8 {
+    const fn polysize(self) -> u8 {
         (match self.0 {
             Poly::B7(_) => crc::cr::POLYSIZE_A::POLYSIZE7,
             Poly::B8(_) => crc::cr::POLYSIZE_A::POLYSIZE8,
@@ -220,7 +220,7 @@ impl Polynomial {
     }
 
     /// Return POL register value.
-    fn pol(self) -> u32 {
+    const fn pol(self) -> u32 {
         match self.0 {
             Poly::B7(pol) | Poly::B8(pol) => pol as u32,
             Poly::B16(pol) => pol as u32,
@@ -229,7 +229,7 @@ impl Polynomial {
     }
 
     /// Return mask for output XOR according to size.
-    fn xor_mask(self) -> u32 {
+    const fn xor_mask(self) -> u32 {
         match self.0 {
             Poly::B7(_) => 0x7F,
             Poly::B8(_) => 0xFF,
@@ -362,8 +362,7 @@ impl Config {
     /// Set whether to reflect the CRC. When enabled, reflection is
     /// [`BitReversal::Byte`] and output reversal enabled. This is simply
     /// a convenience function as many CRC algorithms call for this.
-    pub fn reflect(self, reflect: bool) -> Self {
-        // Rust 1.46 and higher: This function can be const.
+    pub const fn reflect(self, reflect: bool) -> Self {
         if reflect {
             self.reverse_input(Some(BitReversal::Byte))
                 .reverse_output(true)

src/ethernet/eth.rs

@@ -478,7 +478,14 @@ pub unsafe fn new_unchecked<'a>(
                 .dcrcc()
                 .clear_bit()
         });
-        // Set the MAC address
+        // Set the MAC address.
+        // Writes to LR trigger both registers to be loaded into the MAC,
+        // so write to LR last.
+        eth_mac.maca0hr.write(|w| {
+            w.addrhi().bits(
+                u16::from(mac_addr.0[4]) | (u16::from(mac_addr.0[5]) << 8),
+            )
+        });
         eth_mac.maca0lr.write(|w| {
             w.addrlo().bits(
                 u32::from(mac_addr.0[0])
@@ -487,14 +494,6 @@ pub unsafe fn new_unchecked<'a>(
                     | (u32::from(mac_addr.0[3]) << 24),
             )
         });
-        eth_mac.maca0hr.write(
-            |w| {
-                w.addrhi().bits(
-                    u16::from(mac_addr.0[4]) | (u16::from(mac_addr.0[5]) << 8),
-                )
-            }, //.sa().clear_bit()
-               //.mbc().bits(0b000000)
-        );
         // frame filter register
         eth_mac.macpfr.modify(|_, w| {
             w.dntu()
@@ -523,7 +522,7 @@ pub unsafe fn new_unchecked<'a>(
                 .clear_bit()
                 // Receive All
                 .ra()
-                .set_bit()
+                .clear_bit()
                 // Promiscuous mode
                 .pr()
                 .clear_bit()