From 8267acfcba7bfa8584fb837f3aeddbd839da1731 Mon Sep 17 00:00:00 2001
From: Astro <astro@spaceboyz.net>
Date: Wed, 24 Jun 2020 02:08:37 +0200
Subject: [PATCH] eth: latter tuning

---
 experiments/src/main.rs     |  6 +++---
 libboard_zynq/src/eth/rx.rs | 12 +++++++++---
 2 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/experiments/src/main.rs b/experiments/src/main.rs
index 8e685f0..17a0d25 100644
--- a/experiments/src/main.rs
+++ b/experiments/src/main.rs
@@ -184,10 +184,10 @@ if false {
     let eth = zynq::eth::Eth::default(HWADDR.clone());
     println!("Eth on");
 
-    const RX_LEN: usize = 4096;
+    const RX_LEN: usize = 8192;
     // Number of transmission buffers (minimum is two because with
     // one, duplicate packet transmission occurs)
-    const TX_LEN: usize = 4096;
+    const TX_LEN: usize = 8192;
     let eth = eth.start_rx(RX_LEN);
     let mut eth = eth.start_tx(TX_LEN);
 
@@ -217,7 +217,7 @@ if false {
         while let Ok(stream) = TcpStream::accept(TCP_PORT, 0x10_0000, 0x10_0000).await {
             let stats_tx = stats_tx.clone();
             task::spawn(async move {
-                let tx_data = (0..=255).take(65536).collect::<alloc::vec::Vec<u8>>();
+                let tx_data = (0..=255).take(8192).collect::<alloc::vec::Vec<u8>>();
                 loop {
                     // const CHUNK_SIZE: usize = 65536;
                     // match stream.send((0..=255).cycle().take(CHUNK_SIZE)).await {
diff --git a/libboard_zynq/src/eth/rx.rs b/libboard_zynq/src/eth/rx.rs
index 4fb8ac5..e2d9396 100644
--- a/libboard_zynq/src/eth/rx.rs
+++ b/libboard_zynq/src/eth/rx.rs
@@ -83,6 +83,8 @@ impl DescList {
             entry.word1.write(
                 DescWord1::zeroed()
             );
+            l2cache().invalidate_slice(&mut buffer[..]);
+            dcci_slice(&buffer[..]);
         }
 
         DescList {
@@ -108,9 +110,9 @@ impl DescList {
             let word1 = entry.word1.read();
             let len = word1.frame_length_lsbs().into();
             let buffer = &mut self.buffers[self.next][0..len];
-            // Invalidate caches for packet buffer
-            l2cache().invalidate_slice(&mut buffer[..]);
-            dcci_slice(&buffer[..]);
+            // // Invalidate caches for packet buffer
+            // l2cache().invalidate_slice(&mut buffer[..]);
+            // dcci_slice(&buffer[..]);
 
             self.next += 1;
             if self.next >= list_len {
@@ -139,6 +141,10 @@ pub struct PktRef<'a> {
 
 impl<'a> Drop for PktRef<'a> {
     fn drop(&mut self) {
+        // Flush buffer from cache, to be filled by the peripheral
+        // before next read
+        l2cache().invalidate_slice(self.buffer);
+        dcci_slice(self.buffer);
 
         self.entry.word0.modify(|_, w| w.used(false));
         dmb();