[net-next,0/3] net: phy: marvell-88q2xxx: Enable auto negotiation for mv88q2110

Message

Niklas Söderlund Sept. 6, 2024, 1:39 p.m. UTC

Hello,

This series enables auto negotiation for the mv88q2110 device.  
Previously this feature have been disabled for mv88q2110, while enabled 
for other devices supported by this driver.

The initial driver implementation states this is due to the 
configuration sequence provided by the vendor did not work. By comparing 
the initialization sequence of other devices this driver supports and 
the out-of-tree PHY driver for mv88q2110 found in the Renesas BSP [1] I 
was able to figure out a working configuration.

As I have no access to the datasheets of either of these devices it 
would be super if someone who has could sanity check the initialization 
sequence.

With this series I'm able to auto negotiate both 1000Mbps and 100Mbps 
links without issue.

    # ethtool eth0
    Settings for eth0:
            Supported ports: [  ]
            Supported link modes:   100baseT1/Full
                                    1000baseT1/Full
            Supported pause frame use: Symmetric Receive-only
            Supports auto-negotiation: Yes
            Supported FEC modes: Not reported
            Advertised link modes:  100baseT1/Full
                                    1000baseT1/Full
            Advertised pause frame use: No
            Advertised auto-negotiation: Yes
            Advertised FEC modes: Not reported
            Link partner advertised link modes:  100baseT1/Full
                                                 1000baseT1/Full
            Link partner advertised pause frame use: No
            Link partner advertised auto-negotiation: Yes
            Link partner advertised FEC modes: Not reported
            Speed: 1000Mb/s
            Duplex: Full
            Auto-negotiation: on
            master-slave cfg: preferred master
            master-slave status: slave
            Port: Twisted Pair
            PHYAD: 0
            Transceiver: external
            MDI-X: Unknown
            Link detected: yes
            SQI: 15/15

And the performance is good too. Without this change I was not able to 
manually configure a 1000Mbps link, only 100Mbps ones. So this gives a 
huge performance boost for my use-case.

    [  5] local 10.1.0.2 port 5201 connected to 10.1.0.1 port 38346
    [ ID] Interval           Transfer     Bitrate         Retr  Cwnd
    [  5]   0.00-1.00   sec  96.8 MBytes   812 Mbits/sec    0    469 KBytes
    [  5]   1.00-2.00   sec  94.3 MBytes   791 Mbits/sec    0    469 KBytes
    [  5]   2.00-3.00   sec  96.1 MBytes   806 Mbits/sec    0    469 KBytes
    [  5]   3.00-4.00   sec  98.3 MBytes   825 Mbits/sec    0    469 KBytes
    [  5]   4.00-5.00   sec  98.4 MBytes   825 Mbits/sec    0    469 KBytes
    [  5]   5.00-6.00   sec  98.4 MBytes   826 Mbits/sec    0    469 KBytes
    [  5]   6.00-7.00   sec  98.9 MBytes   830 Mbits/sec    0    469 KBytes
    [  5]   7.00-8.00   sec  91.7 MBytes   769 Mbits/sec    0    469 KBytes
    [  5]   8.00-9.00   sec  99.4 MBytes   834 Mbits/sec    0    747 KBytes
    [  5]   9.00-10.00  sec   101 MBytes   851 Mbits/sec    0    747 KBytes

Patch 1/3 and 2/3 are preparation patches that align and move functions 
around as the mv88q2110 code paths can now reuses much of what is done 
for mv88q2220. While patch 3/3 adds the new initialization sequence and 
removes the auto negotiation limit for mv88q2110.

1.  https://github.com/renesas-rcar/linux-bsp/commit/2a1f07d0e722a18188cfe62842b61f2fbc0ba812

Niklas Söderlund (3):
  net: phy: marvell-88q2xxx: Align soft reset for mv88q2110 and
    mv88q2220
  net: phy: marvell-88q2xxx: Make register writer function generic
  net: phy: marvell-88q2xxx: Enable auto negotiation for mv88q2110

 drivers/net/phy/marvell-88q2xxx.c | 124 +++++++++++++++++-------------
 1 file changed, 71 insertions(+), 53 deletions(-)