Re: [PATCH v2 2/2] clk: tegra20: Enable lock-status polling for PLLs

From: Dmitry Osipenko
Date: Fri Aug 31 2018 - 05:45:24 EST


On 8/31/18 12:29 PM, Peter De Schrijver wrote:
> On Thu, Aug 30, 2018 at 09:42:10PM +0300, Dmitry Osipenko wrote:
>> Currently all PLL's on Tegra20 use a hardcoded delay despite of having
>> a lock-status bit. The lock-status polling was disabled ~7 years ago
>> because PLLE was failing to lock and was a suspicion that other PLLs
>> might be faulty too. Other PLLs are okay, hence enable the lock-status
>> polling for them. This reduces delay of any operation that require PLL
>> to lock.
>>
>> Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
>> ---
>>
>> Changelog:
>>
>> v2: Don't enable polling for PLLE as it known to not being able to lock.
>>
>
> This isn't correct. The lock bit of PLLE can declare lock too early, but the
> PLL itself does lock.

Indeed, it locks but can't be polled for the lock-status as it doesn't have the
lock-status bit.

Do you want me to adjust the commit description or it is fine as is?

It is also a bit odd that PLLE has "lock_delay = 0", is it correct?