Re: net: phy: improve pause mode reporting in phy_print_status

Re: net: phy: improve pause mode reporting in phy_print_status

[Geert Uytterhoeven]

Hi Heiner,

On Wed, May 8, 2019 at 8:02 AM Linux Kernel Mailing List
<linux-kernel@vger.kernel.org> wrote:
> Commit:     23bfaa594002f4bba085e0a1ae3c9847b988d816
> Parent:     5db9c74042e3c2168b1f1104d691063f5b662a8b
> Refname:    refs/heads/master
> Web:        https://git.kernel.org/torvalds/c/23bfaa594002f4bba085e0a1ae3c9847b988d816
> Author:     Heiner Kallweit <hkallweit1@gmail.com>
> AuthorDate: Sun May 5 19:03:51 2019 +0200
> Committer:  David S. Miller <davem@davemloft.net>
> CommitDate: Tue May 7 12:40:39 2019 -0700
>
>     net: phy: improve pause mode reporting in phy_print_status
>
>     So far we report symmetric pause only, and we don't consider the local
>     pause capabilities. Let's properly consider local and remote
>     capabilities, and report also asymmetric pause.
>
>     Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
>     Signed-off-by: David S. Miller <davem@davemloft.net>

Due to this commit, I see the folllowing change on Renesas development
boards using either the sh_eth or ravb Ethernet driver:

    -sh-eth ee700000.ethernet eth0: Link is Up - 100Mbps/Full - flow
control rx/tx
    +sh-eth ee700000.ethernet eth0: Link is Up - 100Mbps/Full - flow control off

and

    -ravb e6800000.ethernet eth0: Link is Up - 1Gbps/Full - flow control rx/tx
    +ravb e6800000.ethernet eth0: Link is Up - 1Gbps/Full - flow control off

Adding debug prints reveals that:

    phydev->autoneg = 1
    phydev->pause = 1
    phydev->asym_pause = 0 or 1 (depending on the board)
    local_pause = 0
    local_asym_pause = 0

Is this expected behavior?

Thanks!

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: net: phy: improve pause mode reporting in phy_print_status

[Heiner Kallweit]

On 21.05.2019 15:07, Geert Uytterhoeven wrote:
> Hi Heiner,
> 
Hi Geert,

> On Wed, May 8, 2019 at 8:02 AM Linux Kernel Mailing List
> <linux-kernel@vger.kernel.org> wrote:
>> Commit:     23bfaa594002f4bba085e0a1ae3c9847b988d816
>> Parent:     5db9c74042e3c2168b1f1104d691063f5b662a8b
>> Refname:    refs/heads/master
>> Web:        https://git.kernel.org/torvalds/c/23bfaa594002f4bba085e0a1ae3c9847b988d816
>> Author:     Heiner Kallweit <hkallweit1@gmail.com>
>> AuthorDate: Sun May 5 19:03:51 2019 +0200
>> Committer:  David S. Miller <davem@davemloft.net>
>> CommitDate: Tue May 7 12:40:39 2019 -0700
>>
>>     net: phy: improve pause mode reporting in phy_print_status
>>
>>     So far we report symmetric pause only, and we don't consider the local
>>     pause capabilities. Let's properly consider local and remote
>>     capabilities, and report also asymmetric pause.
>>
>>     Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
>>     Signed-off-by: David S. Miller <davem@davemloft.net>
> 
> Due to this commit, I see the folllowing change on Renesas development
> boards using either the sh_eth or ravb Ethernet driver:
> 
>     -sh-eth ee700000.ethernet eth0: Link is Up - 100Mbps/Full - flow
> control rx/tx
>     +sh-eth ee700000.ethernet eth0: Link is Up - 100Mbps/Full - flow control off
> 
> and
> 
>     -ravb e6800000.ethernet eth0: Link is Up - 1Gbps/Full - flow control rx/tx
>     +ravb e6800000.ethernet eth0: Link is Up - 1Gbps/Full - flow control off
> 
> Adding debug prints reveals that:
> 
>     phydev->autoneg = 1
>     phydev->pause = 1
>     phydev->asym_pause = 0 or 1 (depending on the board)
>     local_pause = 0
>     local_asym_pause = 0
> 
> Is this expected behavior?
> 
Yes. Both local pause parameters being 0 means no pause support is advertised.
Seems like both network drivers miss calls to phy_support_sym_pause or
phy_support_asym_pause respectively to indicate if and which pause modes
the MAC supports.
Before this patch only the remote pause capability was considered.

> Thanks!
> 
> Gr{oetje,eeting}s,
> 
>                         Geert
> 
Heiner