[PATCH net 1/1] net: stmmac: update MAC capabilities when tx queues are updated

[PATCH net 1/1] net: stmmac: update MAC capabilities when tx queues are updated

[Gan, Yi Fang]

From: Michael Sit Wei Hong <michael.wei.hong.sit@intel.com>

Upon boot up, the driver will configure the MAC capabilities based on
the maximum number of tx and rx queues. When the user changes the
tx queues to single queue, the MAC should be capable of supporting Half
Duplex, but the driver does not update the MAC capabilities when it is
configured so.

Using the stmmac_reinit_queues() to check the number of tx queues
and set the MAC capabilities accordingly.

Fixes: 0366f7e06a6b ("net: stmmac: add ethtool support for get/set channels")
Cc: <stable@vger.kernel.org> # 5.17+
Signed-off-by: Michael Sit Wei Hong <michael.wei.hong.sit@intel.com>
Signed-off-by: Gan, Yi Fang <yi.fang.gan@intel.com>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index ed1a5a31a491..7ddc33fa0cb5 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -7172,6 +7172,14 @@ int stmmac_reinit_queues(struct net_device *dev, u32 rx_cnt, u32 tx_cnt)
 			priv->rss.table[i] = ethtool_rxfh_indir_default(i,
 									rx_cnt);
 
+	/* Half-Duplex can only work with single tx queue */
+	if (priv->plat->tx_queues_to_use > 1)
+		priv->phylink_config.mac_capabilities &=
+			~(MAC_10HD | MAC_100HD | MAC_1000HD);
+	else
+		priv->phylink_config.mac_capabilities |=
+			(MAC_10HD | MAC_100HD | MAC_1000HD);
+
 	stmmac_napi_add(dev);
 
 	if (netif_running(dev))
-- 
2.34.1

Re: [PATCH net 1/1] net: stmmac: update MAC capabilities when tx queues are updated

[Russell King (Oracle)]

On Wed, Oct 18, 2023 at 10:31:36AM +0800, Gan, Yi Fang wrote:
> From: Michael Sit Wei Hong <michael.wei.hong.sit@intel.com>
> 
> Upon boot up, the driver will configure the MAC capabilities based on
> the maximum number of tx and rx queues. When the user changes the
> tx queues to single queue, the MAC should be capable of supporting Half
> Duplex, but the driver does not update the MAC capabilities when it is
> configured so.
> 
> Using the stmmac_reinit_queues() to check the number of tx queues
> and set the MAC capabilities accordingly.

There is other setup elsewhere in the driver that fiddles with this in
stmmac_phy_setup(). Maybe provide a helper function so that this
decision making can be made in one function called from both these
locations, so if the decision making for HD support changes, only one
place needs changing?

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!

Re: [PATCH net 1/1] net: stmmac: update MAC capabilities when tx queues are updated

[Paolo Abeni]

On Wed, 2023-10-18 at 08:25 +0100, Russell King (Oracle) wrote:
> On Wed, Oct 18, 2023 at 10:31:36AM +0800, Gan, Yi Fang wrote:
> > From: Michael Sit Wei Hong <michael.wei.hong.sit@intel.com>
> > 
> > Upon boot up, the driver will configure the MAC capabilities based on
> > the maximum number of tx and rx queues. When the user changes the
> > tx queues to single queue, the MAC should be capable of supporting Half
> > Duplex, but the driver does not update the MAC capabilities when it is
> > configured so.
> > 
> > Using the stmmac_reinit_queues() to check the number of tx queues
> > and set the MAC capabilities accordingly.
> 
> There is other setup elsewhere in the driver that fiddles with this in
> stmmac_phy_setup(). Maybe provide a helper function so that this
> decision making can be made in one function called from both these
> locations, so if the decision making for HD support changes, only one
> place needs changing?

Indeed that looks both straight-forward and more robust.

@Gan, Yi Fang: please send a v2 introducing and using such helper,
thanks!

Paolo

RE: [PATCH net 1/1] net: stmmac: update MAC capabilities when tx queues are updated

[Gan, Yi Fang]

Hi Russell King and Paolo,

Thank you for the feedbacks. I already submit V2 with the helper.

BR,
Fang

> -----Original Message-----
> From: Paolo Abeni <pabeni@redhat.com>
> Sent: Thursday, October 19, 2023 6:25 PM
> To: Russell King (Oracle) <linux@armlinux.org.uk>; Gan, Yi Fang
> <yi.fang.gan@intel.com>
> Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>; Jose Abreu
> <joabreu@synopsys.com>; David S . Miller <davem@davemloft.net>; Eric
> Dumazet <edumazet@google.com>; Jakub Kicinski <kuba@kernel.org>;
> Maxime Coquelin <mcoquelin.stm32@gmail.com>; Ong, Boon Leong
> <boon.leong.ong@intel.com>; netdev@vger.kernel.org; linux-stm32@st-md-
> mailman.stormreply.com; linux-arm-kernel@lists.infradead.org; linux-
> kernel@vger.kernel.org; Sit, Michael Wei Hong
> <michael.wei.hong.sit@intel.com>; Looi, Hong Aun <hong.aun.looi@intel.com>;
> Voon, Weifeng <weifeng.voon@intel.com>; Song, Yoong Siang
> <yoong.siang.song@intel.com>
> Subject: Re: [PATCH net 1/1] net: stmmac: update MAC capabilities when tx
> queues are updated
> 
> On Wed, 2023-10-18 at 08:25 +0100, Russell King (Oracle) wrote:
> > On Wed, Oct 18, 2023 at 10:31:36AM +0800, Gan, Yi Fang wrote:
> > > From: Michael Sit Wei Hong <michael.wei.hong.sit@intel.com>
> > >
> > > Upon boot up, the driver will configure the MAC capabilities based
> > > on the maximum number of tx and rx queues. When the user changes the
> > > tx queues to single queue, the MAC should be capable of supporting
> > > Half Duplex, but the driver does not update the MAC capabilities
> > > when it is configured so.
> > >
> > > Using the stmmac_reinit_queues() to check the number of tx queues
> > > and set the MAC capabilities accordingly.
> >
> > There is other setup elsewhere in the driver that fiddles with this in
> > stmmac_phy_setup(). Maybe provide a helper function so that this
> > decision making can be made in one function called from both these
> > locations, so if the decision making for HD support changes, only one
> > place needs changing?
> 
> Indeed that looks both straight-forward and more robust.
> 
> @Gan, Yi Fang: please send a v2 introducing and using such helper, thanks!
> 
> Paolo