Re: [PATCH net-next RFC 5/9] net: dsa: forward hardware timestamping ioctls to switch driver

[Richard Cochran]

On Thu, Sep 28, 2017 at 10:25:34AM -0700, Florian Fainelli wrote:
> This echoes back to Andrew's comments in patch 2, but we may have to
> prefer PHY timestamping over MAC timestamping if both are available?
> Richard, is that usually how the preference should be made?

No, if the MAC supports time stamping, then it will take precedence,
because the MAC driver doesn't know that the PHY also supports this.
In the case where a board design includes the PHYTER (the one and only
PHY PHC) and a MAC PHC, the user must de-select the MAC support in the
Kconfig in order to use the PHYTER.

So in general, we don't support PHC/timestamping simultaneously in the
MAC and PHY.  It would be a lot of work to support this, and the user
timestamping API would have to be extended yet again, and so I think
it is not worth the effort.

Getting back to this patch, it should fall back to PHY timestamping
when the switch device doesn't support timestamping:

case SIOCGHWTSTAMP:
if (ds->ops->port_hwtstamp_get)
return ds->ops->port_hwtstamp_get(ds, port, ifr);
else
return phy_mii_ioctl(dev->phydev, ifr, cmd);

That way, if someone combines a PHYTER with a non-PTP capable switch,
it will just work.

Thanks,
Richard

Re: [PATCH net-next RFC 5/9] net: dsa: forward hardware timestamping ioctls to switch driver

[Vivien Didelot]

Hi Brandon,

Brandon Streiff  writes:

>  static int dsa_slave_ioctl(struct net_device *dev, struct ifreq *ifr, int 
> cmd)
>  {
> + struct dsa_slave_priv *p = netdev_priv(dev);
> + struct dsa_switch *ds = p->dp->ds;
> + int port = p->dp->index;
> +
>   if (!dev->phydev)
>   return -ENODEV;

Move this check below:

>  
> - return phy_mii_ioctl(dev->phydev, ifr, cmd);
> + switch (cmd) {
> + case SIOCGMIIPHY:
> + case SIOCGMIIREG:
> + case SIOCSMIIREG:
> + if (dev->phydev)
> + return phy_mii_ioctl(dev->phydev, ifr, cmd);
> + else
> + return -EOPNOTSUPP;

if (!dev->phydev)
return -ENODEV;

return phy_mii_ioctl(dev->phydev, ifr, cmd);

> + case SIOCGHWTSTAMP:
> + if (ds->ops->port_hwtstamp_get)
> + return ds->ops->port_hwtstamp_get(ds, port, ifr);
> + else
> + return -EOPNOTSUPP;

Here you can replace the else statement with break;

> + case SIOCSHWTSTAMP:
> + if (ds->ops->port_hwtstamp_set)
> + return ds->ops->port_hwtstamp_set(ds, port, ifr);
> + else
> + return -EOPNOTSUPP;

Same here;

> + default:
> + return -EOPNOTSUPP;
> + }

Then drop the default case and return -EOPNOTSUPP after the switch.

>  }


Thanks,

Vivien

Re: [PATCH net-next RFC 5/9] net: dsa: forward hardware timestamping ioctls to switch driver

[Florian Fainelli]

On 09/28/2017 08:25 AM, Brandon Streiff wrote:
> This patch adds support to the dsa slave network device so that
> switch drivers can implement the SIOC[GS]HWTSTAMP ioctls and the
> ethtool timestamp-info interface.
> 
> Signed-off-by: Brandon Streiff 
> ---

>  struct dsa_switch_driver {
> diff --git a/net/dsa/slave.c b/net/dsa/slave.c
> index bf8800d..2cf6a83 100644
> --- a/net/dsa/slave.c
> +++ b/net/dsa/slave.c
> @@ -264,10 +264,34 @@ dsa_slave_fdb_dump(struct sk_buff *skb, struct 
> netlink_callback *cb,
>  
>  static int dsa_slave_ioctl(struct net_device *dev, struct ifreq *ifr, int 
> cmd)
>  {
> + struct dsa_slave_priv *p = netdev_priv(dev);
> + struct dsa_switch *ds = p->dp->ds;
> + int port = p->dp->index;
> +
>   if (!dev->phydev)
>   return -ENODEV;
>  
> - return phy_mii_ioctl(dev->phydev, ifr, cmd);
> + switch (cmd) {
> + case SIOCGMIIPHY:
> + case SIOCGMIIREG:
> + case SIOCSMIIREG:
> + if (dev->phydev)
> + return phy_mii_ioctl(dev->phydev, ifr, cmd);
> + else
> + return -EOPNOTSUPP;
> + case SIOCGHWTSTAMP:
> + if (ds->ops->port_hwtstamp_get)
> + return ds->ops->port_hwtstamp_get(ds, port, ifr);
> + else
> + return -EOPNOTSUPP;
> + case SIOCSHWTSTAMP:
> + if (ds->ops->port_hwtstamp_set)
> + return ds->ops->port_hwtstamp_set(ds, port, ifr);
> + else
> + return -EOPNOTSUPP;
> + default:
> + return -EOPNOTSUPP;
> + }

This echoes back to Andrew's comments in patch 2, but we may have to
prefer PHY timestamping over MAC timestamping if both are available?
Richard, is that usually how the preference should be made?
--
Florian

[PATCH net-next RFC 5/9] net: dsa: forward hardware timestamping ioctls to switch driver

[Brandon Streiff]

This patch adds support to the dsa slave network device so that
switch drivers can implement the SIOC[GS]HWTSTAMP ioctls and the
ethtool timestamp-info interface.

Signed-off-by: Brandon Streiff 
---
 include/net/dsa.h | 15 +++
 net/dsa/slave.c   | 39 ++-
 2 files changed, 53 insertions(+), 1 deletion(-)

diff --git a/include/net/dsa.h b/include/net/dsa.h
index 8dee216..1163af1 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -19,6 +19,7 @@
 #include 
 #include 
 #include 
+#include 
 #include 
 #include 
 
@@ -329,6 +330,12 @@ struct dsa_switch_ops {
   struct ethtool_wolinfo *w);
 
/*
+* ethtool timestamp info
+*/
+   int (*get_ts_info)(struct dsa_switch *ds, int port,
+  struct ethtool_ts_info *ts);
+
+   /*
 * Suspend and resume
 */
int (*suspend)(struct dsa_switch *ds);
@@ -434,6 +441,14 @@ struct dsa_switch_ops {
 int port, struct net_device *br);
void(*crosschip_bridge_leave)(struct dsa_switch *ds, int sw_index,
  int port, struct net_device *br);
+
+   /*
+* PTP functionality
+*/
+   int (*port_hwtstamp_get)(struct dsa_switch *ds, int port,
+struct ifreq *ifr);
+   int (*port_hwtstamp_set)(struct dsa_switch *ds, int port,
+struct ifreq *ifr);
 };
 
 struct dsa_switch_driver {
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index bf8800d..2cf6a83 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -264,10 +264,34 @@ dsa_slave_fdb_dump(struct sk_buff *skb, struct 
netlink_callback *cb,
 
 static int dsa_slave_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 {
+   struct dsa_slave_priv *p = netdev_priv(dev);
+   struct dsa_switch *ds = p->dp->ds;
+   int port = p->dp->index;
+
if (!dev->phydev)
return -ENODEV;
 
-   return phy_mii_ioctl(dev->phydev, ifr, cmd);
+   switch (cmd) {
+   case SIOCGMIIPHY:
+   case SIOCGMIIREG:
+   case SIOCSMIIREG:
+   if (dev->phydev)
+   return phy_mii_ioctl(dev->phydev, ifr, cmd);
+   else
+   return -EOPNOTSUPP;
+   case SIOCGHWTSTAMP:
+   if (ds->ops->port_hwtstamp_get)
+   return ds->ops->port_hwtstamp_get(ds, port, ifr);
+   else
+   return -EOPNOTSUPP;
+   case SIOCSHWTSTAMP:
+   if (ds->ops->port_hwtstamp_set)
+   return ds->ops->port_hwtstamp_set(ds, port, ifr);
+   else
+   return -EOPNOTSUPP;
+   default:
+   return -EOPNOTSUPP;
+   }
 }
 
 static int dsa_slave_port_attr_set(struct net_device *dev,
@@ -876,6 +900,18 @@ static int dsa_slave_set_rxnfc(struct net_device *dev,
return ds->ops->set_rxnfc(ds, p->dp->index, nfc);
 }
 
+static int dsa_slave_get_ts_info(struct net_device *dev,
+struct ethtool_ts_info *ts)
+{
+   struct dsa_slave_priv *p = netdev_priv(dev);
+   struct dsa_switch *ds = p->dp->ds;
+
+   if (!ds->ops->get_ts_info)
+   return -EOPNOTSUPP;
+
+   return ds->ops->get_ts_info(ds, p->dp->index, ts);
+}
+
 static const struct ethtool_ops dsa_slave_ethtool_ops = {
.get_drvinfo= dsa_slave_get_drvinfo,
.get_regs_len   = dsa_slave_get_regs_len,
@@ -896,6 +932,7 @@ static const struct ethtool_ops dsa_slave_ethtool_ops = {
.set_link_ksettings = phy_ethtool_set_link_ksettings,
.get_rxnfc  = dsa_slave_get_rxnfc,
.set_rxnfc  = dsa_slave_set_rxnfc,
+   .get_ts_info= dsa_slave_get_ts_info,
 };
 
 static const struct net_device_ops dsa_slave_netdev_ops = {
-- 
2.1.4