[PATCH net-next 0/3] net: stmmac: Fix HW timestamping

[PATCH net-next 0/3] net: stmmac: Fix HW timestamping

[Jose Abreu]

Hi,

Three fixes for HW timestamping feature, all of them for RX side.

Best regards,
Jose Miguel Abreu

David,

I'm targeting this for -next but teel free to apply this in
your -fixes tree if you think its needed. Though, I don't
think anyone is using HW timestamping because these bugs would
appear immediatly.

Cc: David S. Miller <davem@davemloft.net>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>

Jose Abreu (3):
  net: stmmac: Add missing call to dev_kfree_skb()
  net: stmmac: Fix stmmac_get_rx_hwtstamp()
  net: stmmac: Prevent infinite loop in get_rx_timestamp_status()

 drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c |  2 +-
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c  | 14 +++++++-------
 2 files changed, 8 insertions(+), 8 deletions(-)

-- 
1.9.1

[PATCH net-next 1/3] net: stmmac: Add missing call to dev_kfree_skb()

[Jose Abreu]

When RX HW timestamp is enabled and a frame is discarded we are
not freeing the skb but instead only setting to NULL the entry.

Add a call to dev_kfree_skb_any() so that skb entry is correctly
freed.

Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 0e1b0a3..f7b7906 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -3358,6 +3358,7 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue)
 				 * them in stmmac_rx_refill() function so that
 				 * device can reuse it.
 				 */
+				dev_kfree_skb_any(rx_q->rx_skbuff[entry]);
 				rx_q->rx_skbuff[entry] = NULL;
 				dma_unmap_single(priv->device,
 						 rx_q->rx_skbuff_dma[entry],
-- 
1.9.1

[PATCH net-next 2/3] net: stmmac: Fix stmmac_get_rx_hwtstamp()

[Jose Abreu]

When using GMAC4 the valid timestamp is from CTX next desc but
we are passing the previous desc to get_rx_timestamp_status()
callback.

Fix this and while at it rework a little bit the function logic.

Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index f7b7906..0d3fd3b 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -473,19 +473,18 @@ static void stmmac_get_rx_hwtstamp(struct stmmac_priv *priv, struct dma_desc *p,
 				   struct dma_desc *np, struct sk_buff *skb)
 {
 	struct skb_shared_hwtstamps *shhwtstamp = NULL;
+	struct dma_desc *desc = p;
 	u64 ns;
 
 	if (!priv->hwts_rx_en)
 		return;
+	/* For GMAC4, the valid timestamp is from CTX next desc. */
+	if (priv->plat->has_gmac4)
+		desc = np;
 
 	/* Check if timestamp is available */
-	if (priv->hw->desc->get_rx_timestamp_status(p, priv->adv_ts)) {
-		/* For GMAC4, the valid timestamp is from CTX next desc. */
-		if (priv->plat->has_gmac4)
-			ns = priv->hw->desc->get_timestamp(np, priv->adv_ts);
-		else
-			ns = priv->hw->desc->get_timestamp(p, priv->adv_ts);
-
+	if (priv->hw->desc->get_rx_timestamp_status(desc, priv->adv_ts)) {
+		ns = priv->hw->desc->get_timestamp(desc, priv->adv_ts);
 		netdev_dbg(priv->dev, "get valid RX hw timestamp %llu\n", ns);
 		shhwtstamp = skb_hwtstamps(skb);
 		memset(shhwtstamp, 0, sizeof(struct skb_shared_hwtstamps));
-- 
1.9.1

[PATCH net-next 3/3] net: stmmac: Prevent infinite loop in get_rx_timestamp_status()

[Jose Abreu]

Prevent infinite loop by correctly setting the loop condition to
break when i == 10.

Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
---
 drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c
index e0ef02f..4b286e2 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c
@@ -275,7 +275,7 @@ static int dwmac4_wrback_get_rx_timestamp_status(void *desc, u32 ats)
 					goto exit;
 				i++;
 
-			} while ((ret == 1) || (i < 10));
+			} while ((ret == 1) && (i < 10));
 
 			if (i == 10)
 				ret = -EBUSY;
-- 
1.9.1

Re: [PATCH net-next 0/3] net: stmmac: Fix HW timestamping

[David Miller]

From: Jose Abreu <Jose.Abreu@synopsys.com>
Date: Fri, 20 Oct 2017 14:37:33 +0100

> Three fixes for HW timestamping feature, all of them for RX side.

Series applied to 'net', thanks.