Re: [PATCH 3/4 net] qca_spi: Fix ethtool -G iface tx behavior

Hi Paolo,

Am 23.11.23 um 12:51 schrieb Paolo Abeni:

On Tue, 2023-11-21 at 17:30 +0100, Stefan Wahren wrote:

quoted

After calling ethtool -g it was not possible to adjust the TX ring size
again.

Could you please report the exact command sequence that will fail?

ethtool -g eth1
ethtool -G eth1 tx 8

quoted

The reason for this is that the readonly setting rx_pending get
initialized and after that the range check in qcaspi_set_ringparam()
fails regardless of the provided parameter. Since there is no adjustable
RX ring at all, drop it from qcaspi_get_ringparam().
Fixes: 291ab06ecf67 ("net: qualcomm: new Ethernet over SPI driver for QCA7000")
Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
---
  drivers/net/ethernet/qualcomm/qca_debug.c | 2 --
  1 file changed, 2 deletions(-)

diff --git a/drivers/net/ethernet/qualcomm/qca_debug.c b/drivers/net/ethernet/qualcomm/qca_debug.c
index 6f2fa2a42770..613eb688cba2 100644
--- a/drivers/net/ethernet/qualcomm/qca_debug.c
+++ b/drivers/net/ethernet/qualcomm/qca_debug.c

@@ -252,9 +252,7 @@ qcaspi_get_ringparam(struct net_device *dev, struct ethtool_ringparam *ring,
  {
  	struct qcaspi *qca = netdev_priv(dev);

-	ring->rx_max_pending = 4;
  	ring->tx_max_pending = TX_RING_MAX_LEN;
-	ring->rx_pending = 4;
  	ring->tx_pending = qca->txr.count;
  }

I think it's preferable update qcaspi_set_ringparam() to complete
successfully when the provided arguments don't change the rx_pending
default (4)

Sorry, i didn't get. The whole point is that there is no RX ring at all,
just a TX ring. During the time of writing this driver, i was under the
assumption that the driver needs to provide a rx_pending in
qcaspi_get_ringparam even this is no RX ring. The number 4 represent the
maximum of 4 packets which can be received at once. But it's not a ring.

Best regards

Cheers,

Paolo