From: Konrad Dybcio <konrad.dybcio@linaro.org>
To: Stephan Gerhold <stephan@gerhold.net>
Cc: Andy Gross <agross@kernel.org>,
Bjorn Andersson <andersson@kernel.org>,
Michael Turquette <mturquette@baylibre.com>,
Stephen Boyd <sboyd@kernel.org>,
Georgi Djakov <djakov@kernel.org>, Leo Yan <leo.yan@linaro.org>,
Evan Green <evgreen@chromium.org>,
Marijn Suijten <marijn.suijten@somainline.org>,
linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-clk@vger.kernel.org, linux-pm@vger.kernel.org
Subject: Re: [PATCH v2 04/22] clk: qcom: smd-rpm: Export clock scaling availability
Date: Sat, 10 Jun 2023 20:53:05 +0200 [thread overview]
Message-ID: <b7b1d19c-b87d-b3fd-36aa-374065a45ede@linaro.org> (raw)
In-Reply-To: <40f937bb-0d7e-a237-1672-5905983622ce@linaro.org>
On 10.06.2023 14:15, Konrad Dybcio wrote:
>
>
> On 10.06.2023 13:35, Stephan Gerhold wrote:
>> On Fri, Jun 09, 2023 at 10:19:09PM +0200, Konrad Dybcio wrote:
>>> Before we issue a call to RPM through clk_smd_rpm_enable_scaling() the
>>> clock rate requests will not be commited in hardware. This poses a
>>> race threat since we're accessing the bus clocks directly from within
>>> the interconnect framework.
>>>
>>> Add a marker to indicate that we're good to go with sending new requests
>>> and export it so that it can be referenced from icc.
>>>
>>> Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
>>> ---
>>> drivers/clk/qcom/clk-smd-rpm.c | 9 +++++++++
>>> include/linux/soc/qcom/smd-rpm.h | 2 ++
>>> 2 files changed, 11 insertions(+)
>>>
>>> diff --git a/drivers/clk/qcom/clk-smd-rpm.c b/drivers/clk/qcom/clk-smd-rpm.c
>>> index 937cb1515968..482fe30ee6f0 100644
>>> --- a/drivers/clk/qcom/clk-smd-rpm.c
>>> +++ b/drivers/clk/qcom/clk-smd-rpm.c
>>> @@ -151,6 +151,7 @@
>>> #define to_clk_smd_rpm(_hw) container_of(_hw, struct clk_smd_rpm, hw)
>>>
>>> static struct qcom_smd_rpm *rpmcc_smd_rpm;
>>> +static bool smd_rpm_clk_scaling;
>>>
>>> struct clk_smd_rpm {
>>> const int rpm_res_type;
>>> @@ -385,6 +386,12 @@ static unsigned long clk_smd_rpm_recalc_rate(struct clk_hw *hw,
>>> return r->rate;
>>> }
>>>
>>> +bool qcom_smd_rpm_scaling_available(void)
>>> +{
>>> + return smd_rpm_clk_scaling;
>>> +}
>>> +EXPORT_SYMBOL_GPL(qcom_smd_rpm_scaling_available);
>>> +
>>> static int clk_smd_rpm_enable_scaling(void)
>>> {
>>> int ret;
>>> @@ -410,6 +417,8 @@ static int clk_smd_rpm_enable_scaling(void)
>>> return ret;
>>> }
>>>
>>> + smd_rpm_clk_scaling = true;
>>> +
>>
>> If you move the platform_device_register_data(&rpdev->dev,
>> "icc_smd_rpm", ...) from drivers/soc/qcom/smd-rpm.c to here you can
>> avoid the race completely and drop this API. I think that would be
>> cleaner. And it will likely probe much faster because probe deferral
>> is slow. :)
> Sounds like an idea.. especially since it's pretty much the only
> dependency other than SMDRPM itself!
It sounds great, but to not break bisecting one has to:
1. change the registration in soc/smd-rpm to store rpm ptr in driver
data, in addition to parent driver data
2. change icc/smd-rpm to use the device and not parent data
3. add a platform_device_register_data call in clk-smd-rpm that will
always fail because the device is always registered
4. remove the registration from soc/smd-rpm
I know you'd love to see me break my [PATCH xx/42] record, but I'd say
that deserves its own series and *this* patch could be a good transition
middleground :P
Hopefully Stephen, Bjorn and Georgi won't send a hitman after me for
abusing atomic cross-subsystem merges..
Konrad
>
> Konrad
>>
>> Thanks,
>> Stephan
next prev parent reply other threads:[~2023-06-10 18:53 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-09 20:19 [PATCH v2 00/22] Restructure RPM SMD ICC Konrad Dybcio
2023-06-09 20:19 ` [PATCH v2 01/22] soc: qcom: smd-rpm: Add QCOM_SMD_RPM_STATE_NUM Konrad Dybcio
2023-06-09 20:19 ` [PATCH v2 02/22] soc: qcom: smd-rpm: Use tabs for defines Konrad Dybcio
2023-06-09 20:19 ` [PATCH v2 03/22] clk: qcom: smd-rpm: Move some RPM resources to the common header Konrad Dybcio
2023-06-09 20:19 ` [PATCH v2 04/22] clk: qcom: smd-rpm: Export clock scaling availability Konrad Dybcio
2023-06-10 11:35 ` Stephan Gerhold
2023-06-10 12:15 ` Konrad Dybcio
2023-06-10 18:53 ` Konrad Dybcio [this message]
2023-06-10 19:25 ` Stephan Gerhold
2023-06-10 19:39 ` Konrad Dybcio
2023-06-11 9:20 ` Stephan Gerhold
2023-06-12 12:51 ` Konrad Dybcio
2023-06-12 17:03 ` Konrad Dybcio
2023-06-09 20:19 ` [PATCH v2 05/22] interconnect: qcom: icc-rpm: Introduce keep_alive Konrad Dybcio
2023-06-09 20:19 ` [PATCH v2 06/22] interconnect: qcom: icc-rpm: Allow negative QoS offset Konrad Dybcio
2023-06-09 20:19 ` [PATCH v2 07/22] interconnect: qcom: Fold smd-rpm.h into icc-rpm.h Konrad Dybcio
2023-06-09 20:19 ` [PATCH v2 08/22] interconnect: qcom: smd-rpm: Add rpmcc handling skeleton code Konrad Dybcio
2023-06-09 20:19 ` [PATCH v2 09/22] interconnect: qcom: Add missing headers in icc-rpm.h Konrad Dybcio
2023-06-09 20:19 ` [PATCH v2 10/22] interconnect: qcom: Define RPM bus clocks Konrad Dybcio
2023-06-09 20:19 ` [PATCH v2 11/22] interconnect: qcom: sdm660: Hook up RPM bus clk definitions Konrad Dybcio
2023-06-09 20:19 ` [PATCH v2 12/22] interconnect: qcom: msm8996: " Konrad Dybcio
2023-06-09 20:19 ` [PATCH v2 13/22] interconnect: qcom: qcs404: " Konrad Dybcio
2023-06-09 20:19 ` [PATCH v2 14/22] interconnect: qcom: msm8939: " Konrad Dybcio
2023-06-10 12:02 ` Stephan Gerhold
2023-06-09 20:19 ` [PATCH v2 15/22] interconnect: qcom: msm8916: " Konrad Dybcio
2023-06-10 12:02 ` Stephan Gerhold
2023-06-09 20:19 ` [PATCH v2 16/22] interconnect: qcom: qcm2290: " Konrad Dybcio
2023-06-09 20:19 ` [PATCH v2 17/22] interconnect: qcom: icc-rpm: Control bus rpmcc from icc Konrad Dybcio
2023-06-10 11:58 ` Stephan Gerhold
2023-06-10 12:14 ` Konrad Dybcio
2023-06-10 16:20 ` Stephan Gerhold
2023-06-10 17:54 ` Konrad Dybcio
2023-06-09 20:19 ` [PATCH v2 18/22] clk: qcom: smd-rpm: Separate out interconnect bus clocks Konrad Dybcio
2023-06-09 20:19 ` [PATCH v2 19/22] interconnect: qcom: icc-rpm: Fix bucket number Konrad Dybcio
2023-06-10 17:46 ` Stephan Gerhold
2023-06-10 17:53 ` Konrad Dybcio
2023-06-09 20:19 ` [PATCH v2 20/22] interconnect: qcom: icc-rpm: Set bandwidth on both contexts Konrad Dybcio
2023-06-10 18:00 ` Stephan Gerhold
2023-06-10 18:28 ` Konrad Dybcio
2023-06-10 18:43 ` Stephan Gerhold
2023-06-09 20:19 ` [PATCH v2 21/22] interconnect: qcom: icc-rpm: Set correct bandwidth through RPM bw req Konrad Dybcio
2023-06-10 18:46 ` Stephan Gerhold
2023-06-09 20:19 ` [PATCH v2 22/22] interconnect: qcom: icc-rpm: Fix bandwidth calculations Konrad Dybcio
2023-06-10 19:06 ` Stephan Gerhold
2023-06-10 19:09 ` Konrad Dybcio
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=b7b1d19c-b87d-b3fd-36aa-374065a45ede@linaro.org \
--to=konrad.dybcio@linaro.org \
--cc=agross@kernel.org \
--cc=andersson@kernel.org \
--cc=djakov@kernel.org \
--cc=evgreen@chromium.org \
--cc=leo.yan@linaro.org \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-clk@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=marijn.suijten@somainline.org \
--cc=mturquette@baylibre.com \
--cc=sboyd@kernel.org \
--cc=stephan@gerhold.net \
/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 read-only IMAP folder(s) and NNTP newsgroup(s).