Re: [PATCH regression] net: phy: fix initialization (config_init) for Marvel 88E1116R PHYs

From: Sebastian Hesselbarth
Date: Wed Apr 02 2014 - 18:30:36 EST


On 04/02/2014 11:09 AM, Alexander Holler wrote:
> Am 02.04.2014 02:57, schrieb Florian Fainelli:
>> Could you verify the following two things before your patch gets merged:
>>
>> - how long does it take for your PHY to clear the BMCR_RESET bit, is
>> it more than the allowed time out in
>> drivers/net/phy/phy_device.c::phy_poll_reset
>> - is your PHY powered down (check BMCR_PWRDOWN), if that is the case,
>> we might be hitting some corner case where toggling BMCR_RESET will
>> power it on, but at the expense of waiting longer
>
> I've done two tests with pr_info before and after the two resets in
> m88e1116r_config_init:
>

[...]

> with mdelay (the value after reset is what contains MII_BMCR):
>
> -----------------------
> dmesg | grep -A1 -B1 AHO
> [ 1.090072] mv643xx_eth: MV-643xx 10/100/1000 ethernet driver version
> 1.4
> [ 1.175888] AHO: before first reset
> [ 1.678806] AHO: after first reset 0x0
> [ 1.683281] AHO: before second reset
> [ 2.186288] AHO: after second reset 0x0
> [ 2.191010] mv643xx_eth_port mv643xx_eth_port.0 eth0: port 0 with MAC
> address xx
> --
> [ 2.426349] netpoll: netconsole: device eth0 not up yet, forcing it
> [ 2.505917] AHO: before first reset
> [ 2.605824] usb 1-1: new high-speed USB device number 2 using orion-ehci
> --
> [ 2.829987] hub 1-1:1.0: 4 ports detected
> [ 3.044502] AHO: after first reset 0x0

If the above hex at the end is BMCR..

> [ 3.049133] AHO: before second reset
> [ 3.126110] usb 1-1.1: new high-speed USB device number 3 using
> orion-ehci
> --
> [ 3.526107] usb 1-1.3: device descriptor read/64, error -32
> [ 3.614264] AHO: after second reset 0x0
> [ 3.618708] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready
> --
> [ 21.335730] Adding 2996116k swap on /dev/sda3. Priority:-1 extents:1
> across:2996116k
> [ 28.195942] AHO: before first reset
> [ 28.696270] AHO: after first reset 0x800

.. have you noticed that your PHY enters POWERDOWN here?

Sebastian

> [ 28.696958] AHO: before second reset
> [ 29.197354] AHO: after second reset 0x800
> [ 111.612263] RPC: Registered named UNIX socket transport module.
> -----------------------

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