Re: net: phy: realtek: regression, kernel null pointer dereference

[Vicente Bergas <vicencb@gmail.com>]

On Saturday, May 11, 2019 5:08:19 PM CEST, Andrew Lunn wrote:
> On Sat, May 11, 2019 at 04:46:40PM +0200, Vicente Bergas wrote:
>> On Friday, May 10, 2019 10:28:06 PM CEST, Heiner Kallweit wrote:
>>> On 10.05.2019 17:05, Vicente Bergas wrote:
>>>> Hello,
>>>> there is a regression on linux v5.1-9573-gb970afcfcabd with 
>>>> a kernel null
>>>> pointer dereference.
>>>> The issue is the commit f81dadbcf7fd067baf184b63c179fc392bdb226e
>>>> net: phy: realtek: Add rtl8211e rx/tx delays config ...
>>> The page operation callbacks are missing in the RTL8211E driver.
>>> I just submitted a fix adding these callbacks to few Realtek PHY drivers
>>> including RTl8211E. This should fix the issue.
>> 
>> Hello Heiner,
>> just tried your patch and indeed the NPE is gone. But still no network...
>> The MAC <-> PHY link was working before, so, maybe the rgmii 
>> delays are not
>> correctly configured.
>
> Hi Vicente
>
> What phy-mode do you have in device tree? Have you tried the others?
>
> rmgii
> rmgii-id
> rmgii-rxid
> rmgii-txid
>
> 	Andrew

Hi Andrew,
it is configured as in the vanilla kernel:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/rockchip/rk3399-sapphire.dtsi#n191
,that is,
phy-mode = "rgmii";
There are also these configuration items:
tx_delay = <0x28>;
rx_delay = <0x11>;

Instead of going the trial-and-error way, please, can you suggest a
probably good configuration?

Thanks,
  Vicenç.