Re: [PATCH] net: phy: add suspend_halted module param

From: Florian Fainelli
Date: Mon Feb 24 2014 - 14:38:09 EST


2014-02-24 11:15 GMT-08:00 Andrew Lunn <andrew@xxxxxxx>:
> On Sun, Feb 23, 2014 at 05:58:39PM +0100, Sebastian Hesselbarth wrote:
>> commit 1211ce53077164e0d34641d0ca5fb4d4a7574498
>> ("net: phy: resume/suspend PHYs on attach/detach")
>> introduced a feature to suspend PHYs when entering halted state.
>>
>> Unfortunately, not all bootloaders properly power-up PHYs on reset
>> and fail to access ethernet because the PHY is still powered down.
>>
>> Therefore, we add a boolean module parameter suspend_halted with
>> default value of true. Disabling that parameter prevents PHYs from
>> being suspended when entering halted state.
>
> Hi Sebastian
>
> Am i doing something silly here?

Could the PHY be already suspended during your initial boot? If that
is the case, the first time we all phy_suspend() the flag is true, we
suspend it, and we never wake it again despite changing
suspend_halted. Does it work better if you specify this module
parameter on the initial kernel boot command-line?

>
> root@qnap:/sys/module/libphy/parameters# cat suspend_halted
> Y
> root@qnap:/sys/module/libphy/parameters# echo N > suspend_halted
> root@qnap:/sys/module/libphy/parameters# cat suspend_halted
> N
> root@qnap:/sys/module/libphy/parameters# reboot
> ...
> ...
>
> Net: egiga0 [PRIME]
> Hit any key to stop autoboot: 0
> Send Cmd : 0x68 to UART1
> egiga0 no link
> Using egiga0 device
> TFTP from server 10.0.0.1; our IP address is 10.0.0.2
> Filename 'uImage-qnap'.
> Load address: 0x800000
> Loading: T T
>
> Does not seem to work.
>
> Andrew



--
Florian
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