Ethernet: workaround for permanent RX FIFO overflow bug

kristianpaul · Apr 7, 2011 · d8ddaca · d8ddaca
1 parent 26fba40
commit d8ddaca
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Showing 4 changed files with 30 additions and 9 deletions.
diff --git a/boards/milkymist-one/rtl/system.v b/boards/milkymist-one/rtl/system.v
@@ -213,7 +213,6 @@ always @(posedge sys_clk) begin
 end
 
 assign ac97_rst_n = ~sys_rst;
-assign phy_rst_n = ~sys_rst;
 assign videoin_rst_n = ~sys_rst;
 
 /*
@@ -896,7 +895,7 @@ sysctl #(
 	.csr_addr(4'h1),
 	.ninputs(7),
 	.noutputs(2),
-	.systemid(32'h10034D31) /* 1.0.0 RC3 on M1 */
+	.systemid(32'h10044D31) /* 1.0.0 RC4 on M1 */
 ) sysctl (
 	.sys_clk(sys_clk),
 	.sys_rst(sys_rst),
@@ -1279,7 +1278,8 @@ minimac #(
 	.phy_col(phy_col),
 	.phy_crs(phy_crs),
 	.phy_mii_clk(phy_mii_clk),
-	.phy_mii_data(phy_mii_data)
+	.phy_mii_data(phy_mii_data),
+	.phy_rst_n(phy_rst_n)
 );
 `else
 assign csr_dr_ethernet = 32'd0;

diff --git a/cores/minimac/rtl/minimac.v b/cores/minimac/rtl/minimac.v
@@ -1,6 +1,6 @@
 /*
  * Milkymist VJ SoC
- * Copyright (C) 2007, 2008, 2009, 2010 Sebastien Bourdeauducq
+ * Copyright (C) 2007, 2008, 2009, 2010, 2011 Sebastien Bourdeauducq
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -56,7 +56,8 @@ module minimac #(
 	input phy_col,
 	input phy_crs,
 	output phy_mii_clk,
-	inout phy_mii_data
+	inout phy_mii_data,
+	output phy_rst_n
 );
 
 assign wbrx_cti_o = 3'd0;
@@ -112,6 +113,8 @@ minimac_ctlif #(
 	.phy_mii_data(phy_mii_data)
 );
 
+assign phy_rst_n = ~(rx_rst & tx_rst);
+
 minimac_rx rx(
 	.sys_clk(sys_clk),
 	.sys_rst(sys_rst),

diff --git a/software/include/base/version.h b/software/include/base/version.h
@@ -1,6 +1,6 @@
 #ifndef __VERSION_H
 #define __VERSION_H
 
-#define VERSION "1.0RC3"
+#define VERSION "1.0RC4"
 
 #endif /* __VERSION_H */
diff --git a/software/libnet/microudp.c b/software/libnet/microudp.c
@@ -1,6 +1,6 @@
 /*
  * Milkymist VJ SoC (Software)
- * Copyright (C) 2007, 2008, 2009, 2010 Sebastien Bourdeauducq
+ * Copyright (C) 2007, 2008, 2009, 2010, 2011 Sebastien Bourdeauducq
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -400,13 +400,31 @@ void microudp_start(unsigned char *macaddr, unsigned int ip, void *buffers)
 	CSR_MINIMAC_SETUP = 0;
 }
 
+static void ethernet_reset()
+{
+	int i;
+
+	printf("Resetting PHY\n");
+	CSR_MINIMAC_SETUP = MINIMAC_SETUP_RXRST|MINIMAC_SETUP_TXRST;
+	for(i=0;i<8000;i++)
+		__asm__("nop");
+	CSR_MINIMAC_SETUP = 0;
+}
+
 void microudp_service()
 {
+	static int previous_overflow;
+
 	if(irq_pending() & IRQ_ETHRX) {
 		if(CSR_MINIMAC_SETUP & MINIMAC_SETUP_RXRST) {
 			printf("Minimac RX FIFO overflow!\n");
-			CSR_MINIMAC_SETUP = 0;
-		}
+			if(previous_overflow)
+				ethernet_reset();
+			else
+				CSR_MINIMAC_SETUP = 0;
+			previous_overflow = 1;
+		} else
+			previous_overflow = 0;
 		if(CSR_MINIMAC_STATE0 == MINIMAC_STATE_PENDING) {
 			rxlen = CSR_MINIMAC_COUNT0;
 			rxbuffer = rxbuffer0;