From 23a598f719811fbb1807ed377382fef019b9b3cd Mon Sep 17 00:00:00 2001 From: Michal Simek Date: Mon, 17 Aug 2015 09:58:54 +0200 Subject: [PATCH] net: zynq: Add dummy packet to fix packet duplication issue Target is duplicating packets. IP prefetches another BD and process it when the first one is sent. Adding one dummy BD to the chain fix the problem with packet duplication. Signed-off-by: Michal Simek Acked-by: Joe Hershberger --- drivers/net/zynq_gem.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/net/zynq_gem.c b/drivers/net/zynq_gem.c index 946dc1b6a9..1b5b6fd942 100644 --- a/drivers/net/zynq_gem.c +++ b/drivers/net/zynq_gem.c @@ -46,6 +46,7 @@ /* Wrap bit, last descriptor */ #define ZYNQ_GEM_TXBUF_WRAP_MASK 0x40000000 #define ZYNQ_GEM_TXBUF_LAST_MASK 0x00008000 /* Last buffer */ +#define ZYNQ_GEM_TXBUF_USED_MASK 0x80000000 /* Used by Hw */ #define ZYNQ_GEM_NWCTRL_TXEN_MASK 0x00000008 /* Enable transmit */ #define ZYNQ_GEM_NWCTRL_RXEN_MASK 0x00000004 /* Enable receive */ @@ -405,14 +406,19 @@ static int zynq_gem_send(struct eth_device *dev, void *ptr, int len) u32 addr, size; struct zynq_gem_priv *priv = dev->priv; struct zynq_gem_regs *regs = (struct zynq_gem_regs *)dev->iobase; + struct emac_bd *current_bd = &priv->tx_bd[1]; /* Setup Tx BD */ memset(priv->tx_bd, 0, sizeof(struct emac_bd)); priv->tx_bd->addr = (ulong)ptr; priv->tx_bd->status = (len & ZYNQ_GEM_TXBUF_FRMLEN_MASK) | - ZYNQ_GEM_TXBUF_LAST_MASK | - ZYNQ_GEM_TXBUF_WRAP_MASK; + ZYNQ_GEM_TXBUF_LAST_MASK; + /* Dummy descriptor to mark it as the last in descriptor chain */ + current_bd->addr = 0x0; + current_bd->status = ZYNQ_GEM_TXBUF_WRAP_MASK | + ZYNQ_GEM_TXBUF_LAST_MASK| + ZYNQ_GEM_TXBUF_USED_MASK; /* setup BD */ writel((ulong)priv->tx_bd, ®s->txqbase); -- 2.39.5