Subject: Re: [PATCH 1/3] fixed_phy: handle link-down case

From: Florian Fainelli <[email-masked]>
Date: Tue, 14 Jul 2015 11:28:30 -0700

On 14/07/15 10:11, Stas Sergeev wrote:
> 
> Currently fixed_phy driver recognizes only the link-up state.
> This simple patch adds an implementation of link-down state.
> It fixes the status registers when link is down, and also allows
> to register the fixed-phy with link down without specifying the speed.
> 
> Signed-off-by: Stas Sergeev <[email-masked]>

This does not quite seem to work for me here on two different setups
that use fixed PHYs:

Before patch link up:

# ethtool moca
Settings for moca:
        Supported ports: [ TP AUI BNC MII FIBRE ]
        Supported link modes:   1000baseT/Half 1000baseT/Full
        Supported pause frame use: No
        Supports auto-negotiation: Yes
        Advertised link modes:  1000baseT/Half 1000baseT/Full
        Advertised pause frame use: No
        Advertised auto-negotiation: Yes
        Link partner advertised link modes:  1000baseT/Full
        Link partner advertised pause frame use: No
        Link partner advertised auto-negotiation: No
        Speed: 1000Mb/s
        Duplex: Full
        Port: BNC
        PHYAD: 2
        Transceiver: external
        Auto-negotiation: on
        Supports Wake-on: gs
        Wake-on: d
        SecureOn password: 00:00:00:00:00:00
        Link detected: yes
#

Before patch link down:
# ethtool moca
Settings for moca:
        Supported ports: [ TP AUI BNC MII FIBRE ]
        Supported link modes:   1000baseT/Half 1000baseT/Full
        Supported pause frame use: No
        Supports auto-negotiation: Yes
        Advertised link modes:  1000baseT/Half 1000baseT/Full
        Advertised pause frame use: No
        Advertised auto-negotiation: No
        Speed: 1000Mb/s
        Duplex: Full
        Port: BNC
        PHYAD: 2
        Transceiver: external
        Auto-negotiation: off
        Supports Wake-on: gs
        Wake-on: d
        SecureOn password: 00:00:00:00:00:00
        Link detected: no
#

After patch link up:
# ethtool moca
Settings for moca:
        Supported ports: [ TP AUI BNC MII FIBRE ]
        Supported link modes:   1000baseT/Half 1000baseT/Full
        Supported pause frame use: No
        Supports auto-negotiation: Yes
        Advertised link modes:  1000baseT/Half 1000baseT/Full
        Advertised pause frame use: No
        Advertised auto-negotiation: Yes
        Link partner advertised link modes:  10baseT/Full
        Link partner advertised pause frame use: No
        Link partner advertised auto-negotiation: No
        Speed: 10Mb/s <---- this is not quite the speed we want
        Duplex: Full
        Port: BNC
        PHYAD: 2
        Transceiver: external
        Auto-negotiation: on
        Supports Wake-on: gs
        Wake-on: d
        SecureOn password: 00:00:00:00:00:00
        Link detected: yes
#

After patch link down:

# ethtool moca
Settings for moca:
        Supported ports: [ TP AUI BNC MII FIBRE ]
        Supported link modes:   1000baseT/Half 1000baseT/Full
        Supported pause frame use: No
        Supports auto-negotiation: Yes
        Advertised link modes:  1000baseT/Half 1000baseT/Full
        Advertised pause frame use: No
        Advertised auto-negotiation: No
        Speed: 10Mb/s
        Duplex: Half
        Port: BNC
        PHYAD: 2
        Transceiver: external
        Auto-negotiation: off
        Supports Wake-on: gs
        Wake-on: d
        SecureOn password: 00:00:00:00:00:00
        Link detected: no
#

Does it behave properly for you?

> 
> CC: Florian Fainelli <[email-masked]>
> CC: [email-masked]
> CC: [email-masked]
> ---
>  drivers/net/phy/fixed_phy.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/phy/fixed_phy.c b/drivers/net/phy/fixed_phy.c
> index 1960b46..479b93f 100644
> --- a/drivers/net/phy/fixed_phy.c
> +++ b/drivers/net/phy/fixed_phy.c
> @@ -52,6 +52,10 @@ static int fixed_phy_update_regs(struct fixed_phy *fp)
>  	u16 lpagb = 0;
>  	u16 lpa = 0;
> 
> +	if (!fp->status.link)
> +		goto done;
> +	bmsr |= BMSR_LSTATUS | BMSR_ANEGCOMPLETE;
> +
>  	if (fp->status.duplex) {
>  		bmcr |= BMCR_FULLDPLX;
> 
> @@ -96,15 +100,13 @@ static int fixed_phy_update_regs(struct fixed_phy *fp)
>  		}
>  	}
> 
> -	if (fp->status.link)
> -		bmsr |= BMSR_LSTATUS | BMSR_ANEGCOMPLETE;
> -
>  	if (fp->status.pause)
>  		lpa |= LPA_PAUSE_CAP;
> 
>  	if (fp->status.asym_pause)
>  		lpa |= LPA_PAUSE_ASYM;
> 
> +done:
>  	fp->regs[MII_PHYSID1] = 0;
>  	fp->regs[MII_PHYSID2] = 0;
> 

-- 
Florian