devicetree.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
To: Georgi Djakov <georgi.djakov@linaro.org>, andy.gross@linaro.org
Cc: devicetree@vger.kernel.org, linux-arm-msm@vger.kernel.org,
	linux-soc@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] arm64: dts: msm8916: Move smem below hwlock
Date: Tue, 23 Feb 2016 19:28:35 +0000	[thread overview]
Message-ID: <56CCB2E3.9050309@linaro.org> (raw)
In-Reply-To: <56CCA95C.9070207@linaro.org>



On 23/02/16 18:47, Georgi Djakov wrote:
> On 23.02.16 г. 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.
Shouldn't the actual uart clk provider registration fail/defer probe due 
to missing parent in this case?

--srini
> 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
>

  parent reply	other threads:[~2016-02-23 19:28 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-02-23 17:21 [PATCH] arm64: dts: msm8916: Move smem below hwlock Georgi Djakov
2016-02-23 17:29 ` Srinivas Kandagatla
2016-02-23 18:47   ` Georgi Djakov
     [not found]     ` <56CCA95C.9070207-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
2016-02-23 19:03       ` Andy Gross
2016-02-24 10:31         ` Georgi Djakov
2016-02-23 19:28     ` Srinivas Kandagatla [this message]
2016-02-23 20:18       ` Georgi Djakov
2016-02-23 17:39 ` Mark Rutland
2016-02-24  6:00 ` Bjorn Andersson

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=56CCB2E3.9050309@linaro.org \
    --to=srinivas.kandagatla@linaro.org \
    --cc=andy.gross@linaro.org \
    --cc=devicetree@vger.kernel.org \
    --cc=georgi.djakov@linaro.org \
    --cc=linux-arm-msm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-soc@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).