Re: [PATCH] clk: tegra30: Don't wait for PLL_U lock bit

From: Tuomas Tynkkynen
Date: Mon Aug 05 2013 - 09:05:08 EST


On 08/05/2013 09:38 AM, Prashant Gaikwad wrote:
> On Thursday 01 August 2013 02:34 AM, Stephen Warren wrote:
>> On 07/31/2013 11:42 AM, Tuomas Tynkkynen wrote:
>>> The lock bit on PLL_U does not seem to be working correctly and
>>> sometimes never gets set when waiting for the PLL to come up.
>>> Remove the TEGRA_PLL_USE_LOCK flag to use a constant delay.
>> Peter, Prashant,
>>
>> I think you said that the lock bits should work on Tegra30 (albeit they
>> don't on Tegra20)? Can you remind me if the do/don't?
>>
>> If Peter and Prashant are OK with this patch, feel free to take my ack.
>
> Hi Tuomas,
>
> Sorry for the delayed response. Please make sure that avdd_usb_pll
> regulator is enabled before enabling PLLU and utmip parameters are
> configured properly.

As far as I can see, avdd_usb_pll is connected to the vio_reg regulator on Cardhu,
which is marked as regulator-always-on. And the same regulator is connected to
eg. VDDIO_UART on the chip, so I presume almost nothing would work if that regulator
would not be on...

> If this this regulator is not enabled then you will get this kind of
> timeout when enabling PLLU.
>
> Thanks,
> Prashant
>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-tegra" in
>> the body of a message to majordomo@xxxxxxxxxxxxxxx
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/