From: "J, KEERTHY" <j-keerthy@ti.com>
To: Viresh Kumar <viresh.kumar@linaro.org>
Cc: <vireshk@kernel.org>, <nm@ti.com>, <sboyd@kernel.org>,
<linux-pm@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
<d-gerlach@ti.com>, <t-kristo@ti.com>
Subject: Re: [PATCH 1/2] opp: ti-opp-supply: Dynamically update u_volt_min
Date: Mon, 12 Nov 2018 08:45:39 +0530 [thread overview]
Message-ID: <e383feb1-ba04-7f56-0cd8-257660a95bd3@ti.com> (raw)
In-Reply-To: <20181108055401.btrixinlqcfh22du@vireshk-i7>
On 11/8/2018 11:24 AM, Viresh Kumar wrote:
> On 07-11-18, 10:04, Keerthy wrote:
>> The voltage range (min, max) provided in the device tree is from
>> the data manual and is pretty big, catering to a wide range of devices.
>> On a i2c read/write failure the regulator_set_voltage_triplet function
>> falls back to set voltage between min and max. The min value from Device
>> Tree can be lesser than the optimal value and in that case that can lead
>> to a hang or crash. Hence set the u_volt_min dynamically to the optimal
>> voltage value.
>
> And why shouldn't we fix the DT for this ?
The DT voltages do not cater to the broad range of devices. In some
particular cases the DT min voltage is slightly lower the voltage at
which the device cannot sustain a particular frequency in which case the
device just silently hangs. So best thing to do is to actually read the
device specific voltages dynamically which will guarantee a particular
device sustaining a particular frequency at the optimal voltage.
>
next prev parent reply other threads:[~2018-11-12 3:15 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-11-07 4:34 [PATCH 0/2] opp: ti-opp-supply: Fixes Keerthy
2018-11-07 4:34 ` [PATCH 1/2] opp: ti-opp-supply: Dynamically update u_volt_min Keerthy
2018-11-08 5:54 ` Viresh Kumar
2018-11-12 3:15 ` J, KEERTHY [this message]
2018-11-12 22:05 ` Dave Gerlach
2018-11-07 4:34 ` [PATCH 2/2] opp: ti-opp-supply: Correct the supply in _get_optimal_vdd_voltage call Keerthy
2018-11-12 21:49 ` Dave Gerlach
2018-11-08 5:53 ` [PATCH 0/2] opp: ti-opp-supply: Fixes Viresh Kumar
2018-11-13 4:12 ` Viresh Kumar
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=e383feb1-ba04-7f56-0cd8-257660a95bd3@ti.com \
--to=j-keerthy@ti.com \
--cc=d-gerlach@ti.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=nm@ti.com \
--cc=sboyd@kernel.org \
--cc=t-kristo@ti.com \
--cc=viresh.kumar@linaro.org \
--cc=vireshk@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).