Re: [PATCH v1 3/3] ARM: dts: bcm2711: Enable GENET support for the RPi4

[Stefan Wahren]

Hi Florian,

Am 11.10.19 um 21:31 schrieb Florian Fainelli:
> On 10/11/19 11:48 AM, matthias.bgg@xxxxxxxxxx wrote:
>> From: Matthias Brugger <mbrugger@xxxxxxxx>
>>
>> Enable Gigabit Ethernet support on the Raspberry Pi 4
>> Model B.
>>
>> Signed-off-by: Matthias Brugger <mbrugger@xxxxxxxx>
>>
>> ---
>>
>>  arch/arm/boot/dts/bcm2711-rpi-4-b.dts | 22 ++++++++++++++++++++++
>>  arch/arm/boot/dts/bcm2711.dtsi        | 18 ++++++++++++++++++
>>  2 files changed, 40 insertions(+)
>>
>> diff --git a/arch/arm/boot/dts/bcm2711-rpi-4-b.dts b/arch/arm/boot/dts/bcm2711-rpi-4-b.dts
>> index cccc1ccd19be..958553d62670 100644
>> --- a/arch/arm/boot/dts/bcm2711-rpi-4-b.dts
>> +++ b/arch/arm/boot/dts/bcm2711-rpi-4-b.dts
>> @@ -97,6 +97,28 @@
>>  	status = "okay";
>>  };
>>
>> +&genet {
>> +	phy-handle = <&phy1>;
>> +	phy-mode = "rgmii";
> Can you check that things still work against David Miller's net-next?
> Tree, in particular the BCM54213PE PHY might be matched by the BCM54210E
> entry in drivers/net/phy/broadcom.c and I just fixed an issue in how
> RGMII delays were configured:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git/commit/?id=fea7fda7f50a6059220f83251e70709e45cc8040
>
> This might require you to change the 'phy-mode' property to what is
> appropriate.

i applied your changes, kept the phy-mode above and the interfaces cames
up. But there is a lot of packet loss using ping. After applying this
downstream patch [1] the packet loss doesn't occur.

Is the packet loss a possible cause of the wrong phy-mode and mentioned
patch only a workaround?

[1] -
https://github.com/raspberrypi/linux/commit/360c8e98883f9cd075564be8a7fc25ac0785dee4