[U-Boot] phy ic isn't reset

[Bo Shen]

Hi Andreas,

On 4/18/2013 15:50, Andreas Bießmann wrote:
> Dear Bo Shen,
>
> On 04/18/2013 08:32 AM, Bo Shen wrote:
>> Hi Alex
>>
>> On 4/18/2013 13:27, alex wrote:
>>>
>>> At 2013-04-18 09:23:48,"Bo Shen" <voice.shen at atmel.com> wrote:
>>>> Hi Alex,
>>>>
>>>> On 4/17/2013 18:29, alex wrote:
>>>>> Hi:
>>>>>     I work on one board based on at9g25evk board now. I find one issue
>>>>> that phy IC isn't reset, so network can't work. Only the different
>>>>> crystal with evk board is connected to PHY IC. I copy the phy-reset
>>>>> part
>>>>> of at9260 to at9g25. It can work now. Please the maintainer of at9gx5
>>>>> check this. The modification I do is as below:
>>>>
>>>> As you mentioned, you use different crystal, please specify this in
>>>> detail.
>>>
>>> S3225A package, 50Mhz crystal oscillator. ocean comonents ltd. --->
>>> can work.
>>>
>>> asem series:ASEM1-50.000MHZ-LC-T  ---->can't work.
>>>
>>>>
>>>>> +
>>>>> +#ifdef CONFIG_MACB
>>>>> +int at91sam9x5ek_macb_hw_init(void)
>>>>> +{
>>>>> +        struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
>>>>> +        struct at91_port *pioa = (struct at91_port *)ATMEL_BASE_PIOA;
>>>>> +       struct at91_rstc *rstc = (struct at91_rstc *)ATMEL_BASE_RSTC;
>>>>> +       unsigned long erstl;
>>>>> +
>>>>> +        /* Enable EMAC clock */
>>>>> +        writel(1 << ATMEL_ID_EMAC0, &pmc->pcer);
>>>>> +
>>>>> +       erstl = readl(&rstc->mr) & AT91_RSTC_MR_ERSTL_MASK;
>>>>> +
>>>>> +       /* Need to reset PHY -> 500ms reset */
>>>>> +       writel(AT91_RSTC_KEY | AT91_RSTC_MR_ERSTL(13) |
>>>>> +                       AT91_RSTC_MR_URSTEN, &rstc->mr);
>>>>> +
>>>>> +       writel(AT91_RSTC_KEY | AT91_RSTC_CR_EXTRST, &rstc->cr);
>>>>> +
>>>>> +       /* Wait for end hardware reset */
>>>>> +       while (!(readl(&rstc->sr) & AT91_RSTC_SR_NRSTL))
>>>>> +               ;
>>>>> +
>>>>> +       /* Restore NRST value */
>>>>> +       writel(AT91_RSTC_KEY | erstl | AT91_RSTC_MR_URSTEN,
>>>>> +                       &rstc->mr);
>>>>> +
>>>>> +       at91_macb_hw_init();
>>>>> +}
>>>>> +#endif
>>>>
>>>> On at91sam9g25ek, it don't need this patch. The network work properly.
>>>>
>>>> Btw, please help provide the log information for why not ethernet
>>>> doesn't work.
>>>
>>>   From at91sam9g25ek side, no any error. If you only plug network line
>>> , the network traffic led is always off, that is,DM9161AEP doesn't
>>> check this change.
>>> Even if I add this patch, no any defect, right?
>>
>> I won't suggest do like this, if you use reset controller, it will
>> assert nRST pin. If one more device use nRST, it will also reset other
>> device. if only PHY use nRST and no other consideration, I think it is OK.
>
> I would like to point out that older atmel eval kits use this trick
> heavily. This is due to missing pullup/pulldown on the board, therefore
> it is required to setup some gpio first and then issue a reset (again)
> to the PHY cause it is misconfigured. Maybe this can also be esablished
> with some (R)MII communication, but thats how it is implemented currently.

Thanks for this information.

> Regarding the crystal, what is the root cause of your issue? Does it not
> oscillate or is your PHY 'mis-configured' in means of wrong initial
> setup on configuration lines?
> In both cases I recommend to find a HW solution for the final product.

Hi Alex,
   Please check your issue according to Andreas' suggestion. And try to 
fix it through HW solution.

Best Regards,
Bo Shen

> Best regards
>
> Andreas Bießmann
>