[PATCH net-next] net: fec: Clear and enable MIB counters on imx51

[PATCH net-next] net: fec: Clear and enable MIB counters on imx51

[Andrew Lunn]

Both the IMX51 and IMX53 datasheet indicates that the MIB counters
should be cleared during setup. Otherwise random numbers are returned
via ethtool -S.  Add a quirk and a function to do this.

Tested on an IMX51.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
---
 drivers/net/ethernet/freescale/fec.h      |  4 ++++
 drivers/net/ethernet/freescale/fec_main.c | 27 ++++++++++++++++++++++++---
 2 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h
index 5ea740b4cf14..38c7b21e5d63 100644
--- a/drivers/net/ethernet/freescale/fec.h
+++ b/drivers/net/ethernet/freescale/fec.h
@@ -446,6 +446,10 @@ struct bufdesc_ex {
 #define FEC_QUIRK_HAS_COALESCE		(1 << 13)
 /* Interrupt doesn't wake CPU from deep idle */
 #define FEC_QUIRK_ERR006687		(1 << 14)
+/* The MIB counters should be cleared and enabled during
+ * initialisation.
+ */
+#define FEC_QUIRK_MIB_CLEAR		(1 << 15)
 
 struct bufdesc_prop {
 	int qid;
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index f7c8649fd28f..297fd196c879 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -89,10 +89,10 @@ static struct platform_device_id fec_devtype[] = {
 		.driver_data = 0,
 	}, {
 		.name = "imx25-fec",
-		.driver_data = FEC_QUIRK_USE_GASKET,
+		.driver_data = FEC_QUIRK_USE_GASKET | FEC_QUIRK_MIB_CLEAR,
 	}, {
 		.name = "imx27-fec",
-		.driver_data = 0,
+		.driver_data = FEC_QUIRK_MIB_CLEAR,
 	}, {
 		.name = "imx28-fec",
 		.driver_data = FEC_QUIRK_ENET_MAC | FEC_QUIRK_SWAP_FRAME |
@@ -184,6 +184,9 @@ MODULE_PARM_DESC(macaddr, "FEC Ethernet MAC address");
 #define FEC_RACC_SHIFT16	BIT(7)
 #define FEC_RACC_OPTIONS	(FEC_RACC_IPDIS | FEC_RACC_PRODIS)
 
+/* MIB Control Register */
+#define FEC_MIB_CTRLSTAT_DISABLE	BIT(31)
+
 /*
  * The 5270/5271/5280/5282/532x RX control register also contains maximum frame
  * size bits. Other FEC hardware does not, so we need to take that into
@@ -2356,6 +2359,21 @@ static int fec_enet_get_sset_count(struct net_device *dev, int sset)
 	}
 }
 
+static void fec_enet_clear_ethtool_stats(struct net_device *dev)
+{
+	struct fec_enet_private *fep = netdev_priv(dev);
+	int i;
+
+	/* Disable MIB statistics counters */
+	writel(FEC_MIB_CTRLSTAT_DISABLE, fep->hwp + FEC_MIB_CTRLSTAT);
+
+	for (i = 0; i < ARRAY_SIZE(fec_stats); i++)
+		writel(0, fep->hwp + fec_stats[i].offset);
+
+	/* Don't disable MIB statistics counters */
+	writel(0, fep->hwp + FEC_MIB_CTRLSTAT);
+}
+
 #else	/* !defined(CONFIG_M5272) */
 #define FEC_STATS_SIZE	0
 static inline void fec_enet_update_ethtool_stats(struct net_device *dev)
@@ -3182,7 +3200,10 @@ static int fec_enet_init(struct net_device *ndev)
 
 	fec_restart(ndev);
 
-	fec_enet_update_ethtool_stats(ndev);
+	if (fep->quirks & FEC_QUIRK_MIB_CLEAR)
+		fec_enet_clear_ethtool_stats(ndev);
+	else
+		fec_enet_update_ethtool_stats(ndev);
 
 	return 0;
 }
-- 
2.11.0

Re: [PATCH net-next] net: fec: Clear and enable MIB counters on imx51

[Fabio Estevam]

On Tue, Jun 6, 2017 at 10:57 PM, Andrew Lunn <andrew@lunn.ch> wrote:
> Both the IMX51 and IMX53 datasheet indicates that the MIB counters
> should be cleared during setup. Otherwise random numbers are returned
> via ethtool -S.  Add a quirk and a function to do this.
>
> Tested on an IMX51.
>
> Signed-off-by: Andrew Lunn <andrew@lunn.ch>

Thanks for the fix:

Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>

Re: [PATCH net-next] net: fec: Clear and enable MIB counters on imx51

[David Miller]

From: Andrew Lunn <andrew@lunn.ch>
Date: Wed,  7 Jun 2017 03:57:09 +0200

> Both the IMX51 and IMX53 datasheet indicates that the MIB counters
> should be cleared during setup. Otherwise random numbers are returned
> via ethtool -S.  Add a quirk and a function to do this.
> 
> Tested on an IMX51.
> 
> Signed-off-by: Andrew Lunn <andrew@lunn.ch>

Applied, thanks.

Re: [PATCH net-next] net: fec: Clear and enable MIB counters on imx51

[Paul Gortmaker]

On Wed, Jun 7, 2017 at 10:07 AM, David Miller <davem@davemloft.net> wrote:
> From: Andrew Lunn <andrew@lunn.ch>
> Date: Wed,  7 Jun 2017 03:57:09 +0200
>
>> Both the IMX51 and IMX53 datasheet indicates that the MIB counters
>> should be cleared during setup. Otherwise random numbers are returned
>> via ethtool -S.  Add a quirk and a function to do this.

Seems to break one of the automated linux-next builds:

http://kisskb.ellerman.id.au/kisskb/buildresult/13057702/

A mindless automated bisect reports:

2b30842b23b9e6796c7bd5f0916fd2ebf6b7d633 is the first bad commit
commit 2b30842b23b9e6796c7bd5f0916fd2ebf6b7d633
Author: Andrew Lunn <andrew@lunn.ch>
Date:   Wed Jun 7 03:57:09 2017 +0200

    net: fec: Clear and enable MIB counters on imx51

Paul.

Re: [PATCH net-next] net: fec: Clear and enable MIB counters on imx51

[Fabio Estevam]

Hi Paul,

On Fri, Jun 9, 2017 at 10:01 PM, Paul Gortmaker
<paul.gortmaker@windriver.com> wrote:

> Seems to break one of the automated linux-next builds:
>
> http://kisskb.ellerman.id.au/kisskb/buildresult/13057702/
>
> A mindless automated bisect reports:
>
> 2b30842b23b9e6796c7bd5f0916fd2ebf6b7d633 is the first bad commit
> commit 2b30842b23b9e6796c7bd5f0916fd2ebf6b7d633
> Author: Andrew Lunn <andrew@lunn.ch>
> Date:   Wed Jun 7 03:57:09 2017 +0200
>
>     net: fec: Clear and enable MIB counters on imx51

This should fix it:

--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -2379,6 +2379,10 @@ static void fec_enet_clear_ethtool_stats(struct
net_device *dev)
 static inline void fec_enet_update_ethtool_stats(struct net_device *dev)
 {
 }
+
+static inline void fec_enet_clear_ethtool_stats(struct net_device *dev)
+{
+}
 #endif /* !defined(CONFIG_M5272) */

 /* ITR clock source is enet system clock (clk_ahb).

Will test it and submit a formal patch in case it works.

Thanks