From 31bfb54667a02a4a8bba1221d3ea9812fc75a90b Mon Sep 17 00:00:00 2001
From: Florent Kermarrec <florent@enjoy-digital.fr>
Date: Fri, 9 Aug 2019 13:26:31 +0200
Subject: [PATCH] software/libbase/mdio: set data before clock, revert two
 cycle turnaround and test with different phys

---
 litex/soc/software/libbase/mdio.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/litex/soc/software/libbase/mdio.c b/litex/soc/software/libbase/mdio.c
index 362e274c4..770c25e99 100644
--- a/litex/soc/software/libbase/mdio.c
+++ b/litex/soc/software/libbase/mdio.c
@@ -16,15 +16,17 @@ static void raw_write(unsigned int word, int bitcount)
 	word <<= 32 - bitcount;
 	while(bitcount > 0) {
 		if(word & 0x80000000) {
+			ethphy_mdio_w_write(MDIO_DO|MDIO_OE);
+			delay();
 			ethphy_mdio_w_write(MDIO_CLK|MDIO_DO|MDIO_OE);
 			delay();
 			ethphy_mdio_w_write(MDIO_DO|MDIO_OE);
-			delay();
 		} else {
+			ethphy_mdio_w_write(MDIO_OE);
+			delay();
 			ethphy_mdio_w_write(MDIO_CLK|MDIO_OE);
 			delay();
 			ethphy_mdio_w_write(MDIO_OE);
-			delay();
 		}
 		word <<= 1;
 		bitcount--;
@@ -39,22 +41,26 @@ static unsigned int raw_read(void)
 	word = 0;
 	for(i=0;i<16;i++) {
 		word <<= 1;
+		if(ethphy_mdio_r_read() & MDIO_DI)
+			word |= 1;
 		ethphy_mdio_w_write(MDIO_CLK);
 		delay();
 		ethphy_mdio_w_write(0);
 		delay();
-		if(ethphy_mdio_r_read() & MDIO_DI)
-			word |= 1;
 	}
 	return word;
 }
 
 static void raw_turnaround(void)
 {
+	delay();
 	ethphy_mdio_w_write(MDIO_CLK);
 	delay();
 	ethphy_mdio_w_write(0);
 	delay();
+	ethphy_mdio_w_write(MDIO_CLK);
+	delay();
+	ethphy_mdio_w_write(0);
 }
 
 void mdio_write(int phyadr, int reg, int val)