From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robin Murphy Subject: Re: [PATCH RFT v1 1/3] drm/panfrost: enable devfreq based the "operating-points-v2" property Date: Wed, 8 Jan 2020 14:20:21 +0000 Message-ID: References: <20200107230626.885451-1-martin.blumenstingl@googlemail.com> <20200107230626.885451-2-martin.blumenstingl@googlemail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Content-Language: en-GB Sender: linux-kernel-owner@vger.kernel.org To: Martin Blumenstingl Cc: dri-devel@lists.freedesktop.org, alyssa@rosenzweig.io, steven.price@arm.com, tomeu.vizoso@collabora.com, robh@kernel.org, linux-kernel@vger.kernel.org, daniel@ffwll.ch, airlied@linux.ie, linux-amlogic@lists.infradead.org, linux-rockchip@lists.infradead.org, Sudeep Holla List-Id: linux-rockchip.vger.kernel.org [ +Sudeep ] On 08/01/2020 12:38 pm, Martin Blumenstingl wrote: > Hi Robin, > > On Wed, Jan 8, 2020 at 12:18 PM Robin Murphy wrote: >> >> On 07/01/2020 11:06 pm, Martin Blumenstingl wrote: >>> Decouple the check to see whether we want to enable devfreq for the GPU >>> from dev_pm_opp_set_regulators(). This is preparation work for adding >>> back support for regulator control (which means we need to call >>> dev_pm_opp_set_regulators() before dev_pm_opp_of_add_table(), which >>> means having a check for "is devfreq enabled" that is not tied to >>> dev_pm_opp_of_add_table() makes things easier). >> >> Hmm, what about cases like the SCMI DVFS protocol where the OPPs are >> dynamically discovered rather than statically defined in DT? > where can I find such an example (Amlogic SoCs use SCPI instead of > SCMI, so I don't think that I have any board with SCMI support) or > some documentation? > (I could only find SCPI clock and CPU DVFS implementations, but no > generic "OPPs for any device" implementation) On closer inspection I think this applies to the SCPI DVFS protocol too[1]. AIUI the fact that neither is wired up to a devfreq driver yet is merely due to lack of demand and suitable systems to develop/test on so far - the panfrost devfreq code is only now looking like the first viable upstream use-case ;) Robin. [1] http://infocenter.arm.com/help/topic/com.arm.doc.dui0922g/BABFEBCD.html