Re: [PATCH] arm64: dts: msm8916: Move smem below hwlock
From: Georgi Djakov
Date: Tue Feb 23 2016 - 13:49:11 EST
On 23.02.16 Ð. 19:29, Srinivas Kandagatla wrote:
>
>
> On 23/02/16 17:21, Georgi Djakov wrote:
>> When the SMEM is probed it defers as it depends on the hardware lock, which
>> is not available yet. But the SMD bus and RPM regulators and clocks depend
>> on SMEM and they defer too. The problem with this is that the order of
>> registering the devices is not optimal and also we may end with messed
>> up serial console as the RPM clocks are not registered yet..
> I noticed the same issue but was wondering why would we end up with messed up serial console?
>
> Could you add more details on why serial console is messed up?
>
> I thought, serial driver has nothing to do with the rpm clocks directly!
>
If we don't have the rpm clocks registered, the uart clock is an orphan
and when clk_get_rate() is called on orphan clocks it returns 0 as rate.
In our case the msm_serial driver calls clk_get_rate() and gets 0 rate
as the parent rpm clock has not registered yet. The result is that the
baudrate is set incorrectly.
BR,
Georgi