[PATCH 4/4] net/designware: add explicit reset of {tx|rx}_currdescnum

[Ian Abbott]

Driver "init" function might be called multiple times.
On every "init" Tx/Rx buffer descriptors are initialized: "descs_init"
-> "{tx|rx}_descs_init".

In its turn those init functions set MAC's "{tx|rx}desclistaddr" to
point on the first buffer descriptor in the list.

So CPU to start operation from the first buffer descriptor as well after
every "init" we have to reset "{tx|rx}_currdescnum".

[Original U-Boot patch by Alexey Brodkin <abrodkin at synopsys.com>]

Signed-off-by: Ian Abbott <abbotti at mev.co.uk>
---
 drivers/net/designware.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/designware.c b/drivers/net/designware.c
index 6702d4c..bd20a87 100644
--- a/drivers/net/designware.c
+++ b/drivers/net/designware.c
@@ -176,6 +176,7 @@ static void tx_descs_init(struct eth_device *dev)
 	desc_p->dmamac_next = &desc_table_p[0];
 
 	writel((ulong)&desc_table_p[0], &dma_p->txdesclistaddr);
+	priv->tx_currdescnum = 0;
 }
 
 static void rx_descs_init(struct eth_device *dev)
@@ -207,6 +208,7 @@ static void rx_descs_init(struct eth_device *dev)
 	desc_p->dmamac_next = &desc_table_p[0];
 
 	writel((ulong)&desc_table_p[0], &dma_p->rxdesclistaddr);
+	priv->rx_currdescnum = 0;
 }
 
 static void descs_init(struct eth_device *dev)
-- 
2.10.1