From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A75DDC83005 for ; Sun, 11 Jun 2023 09:21:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229777AbjFKJVC (ORCPT ); Sun, 11 Jun 2023 05:21:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47922 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229570AbjFKJU7 (ORCPT ); Sun, 11 Jun 2023 05:20:59 -0400 Received: from mo4-p01-ob.smtp.rzone.de (mo4-p01-ob.smtp.rzone.de [85.215.255.54]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2AC5F173B; Sun, 11 Jun 2023 02:20:56 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1686475255; cv=none; d=strato.com; s=strato-dkim-0002; b=C0qjHhlylhb7WQO68W5yOLY7+82DBv5Sjwn4Vavvik/XYiCZ97ypMAADj9qXIHkhyT GnA4FFmJ+ik4RQdv2X0EIbeZe7d9x0IE3nKazwd9bJkskl38edBkdojJlvinJfNet6aQ GZXpA/aNml7SO3BcIc1Q+yGJd/avLSmUX7jGYW8De+ZRMmY9kzq/7VqattoQs1RAF7Yj 37z6yk4z45Ul2I5BQ6miSAKIMBQjaLu7xjlAdldxN6S3p3CQBbjD68NTzpelh+nmb/d3 CFGuYQaeTJ8ELqudKVJ3dfAgs+O/4zp+lNJPbwgNEfX/Cdf0GMK7EZ+060RsQtEoJrKg E8aQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; t=1686475255; s=strato-dkim-0002; d=strato.com; h=In-Reply-To:References:Message-ID:Subject:Cc:To:From:Date:Cc:Date: From:Subject:Sender; bh=4mKf/VEq1qjA8SMzrQnOE6vF0s+OB1YlRbk6YIxSLLQ=; b=Beij99zB5E9+WBKKorN15ItB/v7NawJsCtbLzlqnLW7JmQEM8Vj80qNgYdrSFMQkYH /KHk1sGLYvJLd67VVSnNSknOOuKZlnGNII4jgzePFjYKbgrIq6EL1bbNrxFsnh/J26vr 9SdYk9i/SqtiWHl5VTCVJeOUXcZ0yf6uQz9CEvfI1byV53GfjEgALFb3a14BYVzHgc98 CXv8Y/NQ34edcHHNX2Epb07+x2Sl5u+BM4vPxA2ovtWQWSoOjTrWRUT5yZIOadaBrdRn ZSanott41S7OnFdJI7bcUtWuzeTNUy5Td76Q4ruZQ5BQYkejinFUIKyKgYFKLnWVVPTI kYQQ== ARC-Authentication-Results: i=1; strato.com; arc=none; dkim=none X-RZG-CLASS-ID: mo01 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; t=1686475255; s=strato-dkim-0002; d=gerhold.net; h=In-Reply-To:References:Message-ID:Subject:Cc:To:From:Date:Cc:Date: From:Subject:Sender; bh=4mKf/VEq1qjA8SMzrQnOE6vF0s+OB1YlRbk6YIxSLLQ=; b=Wk0kbmzzRwixKmmR4KIGEF8TQq+I3H69ahtCkWHKwe4vw/QSktH296ZwHxrD8bj+PW F3RAmOwdjA2zhLbnitB/UPBK+7dkLCLTLPg/vXYMMxJ9k9isOsk/iUSzx2A/xaSi0HBz KPdiWQF5XYYzqzGvDLU4+xnVyIHCW/7EElaE7sagEJSFE/LHO7GouPLiRud+PhD9or2g KYUnZ1aygRzTaYjRxFWp2NqlBKplvRJuFAdi0b5RO40LAChPu+2KF6wVshp09MuzTYb1 ZxfOIQ7bMG84ZpQLqWOoj1fvNRPwHA09MMbVeXTZzU1RzckcYPCu2pIboYZ+RDmfjs3t 1Tfw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; t=1686475255; s=strato-dkim-0003; d=gerhold.net; h=In-Reply-To:References:Message-ID:Subject:Cc:To:From:Date:Cc:Date: From:Subject:Sender; bh=4mKf/VEq1qjA8SMzrQnOE6vF0s+OB1YlRbk6YIxSLLQ=; b=3I8q3VrNYCz6HcVzGPjLYnkkQeIPufFtnDFXDGB+/rc+7bfYUXhUl0NJJLGgn6ktwA F3RnzSaExvDUD2NXvGCQ== X-RZG-AUTH: ":P3gBZUipdd93FF5ZZvYFPugejmSTVR2nRPhVOQ/OcYgojyw4j34+u261EJF5OxJD4paA95nh" Received: from gerhold.net by smtp.strato.de (RZmta 49.5.3 DYNA|AUTH) with ESMTPSA id Z82ec2z5B9KsRJ3 (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256 bits)) (Client did not present a certificate); Sun, 11 Jun 2023 11:20:54 +0200 (CEST) Date: Sun, 11 Jun 2023 11:20:46 +0200 From: Stephan Gerhold To: Konrad Dybcio Cc: Andy Gross , Bjorn Andersson , Michael Turquette , Stephen Boyd , Georgi Djakov , Leo Yan , Evan Green , Marijn Suijten , 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 Message-ID: References: <20230526-topic-smd_icc-v2-0-e5934b07d813@linaro.org> <20230526-topic-smd_icc-v2-4-e5934b07d813@linaro.org> <40f937bb-0d7e-a237-1672-5905983622ce@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Jun 10, 2023 at 09:39:00PM +0200, Konrad Dybcio wrote: > On 10.06.2023 21:25, Stephan Gerhold wrote: > > On Sat, Jun 10, 2023 at 08:53:05PM +0200, Konrad Dybcio wrote: > >> 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 > >>>>> --- > >>>>> 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 > >> > > > > Logically the icc_smd_rpm device still fits better as child of > > smd-rpm and not clk-smd-rpm. So I would probably just continue > > registering it on the parent device from clk-smd-rpm. > > Then there are no changes necessary in icc_smd_rpm. > > > > You could use this. Both touched files are Bjorn-maintained so should be > > manageable to have it in one commit. (note: compile-tested only) > > > > Thanks, > > Stephan > > > > From a2610adb2551b01e76b9de8e4cbcc89853814a8f Mon Sep 17 00:00:00 2001 > > From: Stephan Gerhold > > Date: Sat, 10 Jun 2023 21:19:48 +0200 > > Subject: [PATCH] soc: qcom: smd-rpm: Move icc_smd_rpm registration to > > clk-smd-rpm > > > > icc_smd_rpm will do bus clock votes itself rather than taking the > > unnecessary detour through the clock subsystem. However, it can only > > do that after the clocks have been handed off and scaling has been > > enabled in the RPM in clk-smd-rpm. > > > > Move the icc_smd_rpm registration from smd-rpm.c to clk-smd-rpm.c > > to avoid any possible races. icc_smd_rpm gets the driver data from > > the smd-rpm device, so still register the platform device on the > > smd-rpm parent device. > > > > Signed-off-by: Stephan Gerhold > > --- > Generally it looks good.. I'll give it a spin next week. One > thing below. > > > drivers/clk/qcom/clk-smd-rpm.c | 21 +++++++++++++++++++++ > > drivers/soc/qcom/smd-rpm.c | 23 +---------------------- > > 2 files changed, 22 insertions(+), 22 deletions(-) > > > > diff --git a/drivers/clk/qcom/clk-smd-rpm.c b/drivers/clk/qcom/clk-smd-rpm.c > > index e4de74b68797..91adb16889b3 100644 > > --- a/drivers/clk/qcom/clk-smd-rpm.c > > +++ b/drivers/clk/qcom/clk-smd-rpm.c > > @@ -1302,12 +1302,20 @@ static struct clk_hw *qcom_smdrpm_clk_hw_get(struct of_phandle_args *clkspec, > > return desc->clks[idx] ? &desc->clks[idx]->hw : ERR_PTR(-ENOENT); > > } > > > > +static void rpm_smd_unregister_icc(void *data) > > +{ > > + struct platform_device *icc_pdev = data; > > + > > + platform_device_unregister(icc_pdev); > > +} > > + > > static int rpm_smd_clk_probe(struct platform_device *pdev) > > { > > int ret; > > size_t num_clks, i; > > struct clk_smd_rpm **rpm_smd_clks; > > const struct rpm_smd_clk_desc *desc; > > + struct platform_device *icc_pdev; > > > > rpmcc_smd_rpm = dev_get_drvdata(pdev->dev.parent); > > if (!rpmcc_smd_rpm) { > > @@ -1357,6 +1365,19 @@ static int rpm_smd_clk_probe(struct platform_device *pdev) > > if (ret) > > goto err; > > > > + icc_pdev = platform_device_register_data(pdev->dev.parent, > > + "icc_smd_rpm", -1, NULL, 0); > > + if (IS_ERR(icc_pdev)) { > > + dev_err(&pdev->dev, "Failed to register icc_smd_rpm device: %pE\n", > > + icc_pdev); > > + /* No need to unregister clocks because of this */ > > + } else { > > + ret = devm_add_action_or_reset(&pdev->dev, rpm_smd_unregister_icc, > > + icc_pdev); > > + if (ret) > > + goto err; > > + } > > + > > return 0; > > err: > > dev_err(&pdev->dev, "Error registering SMD clock driver (%d)\n", ret); > > diff --git a/drivers/soc/qcom/smd-rpm.c b/drivers/soc/qcom/smd-rpm.c > > index 0c1aa809cc4e..427dd5392b82 100644 > > --- a/drivers/soc/qcom/smd-rpm.c > > +++ b/drivers/soc/qcom/smd-rpm.c > > @@ -19,7 +19,6 @@ > > /** > > * struct qcom_smd_rpm - state of the rpm device driver > > * @rpm_channel: reference to the smd channel > > - * @icc: interconnect proxy device > > * @dev: rpm device > > * @ack: completion for acks > > * @lock: mutual exclusion around the send/complete pair > > @@ -27,7 +26,6 @@ > > */ > > struct qcom_smd_rpm { > > struct rpmsg_endpoint *rpm_channel; > > - struct platform_device *icc; > > struct device *dev; > > > > struct completion ack; > > @@ -197,7 +195,6 @@ static int qcom_smd_rpm_callback(struct rpmsg_device *rpdev, > > static int qcom_smd_rpm_probe(struct rpmsg_device *rpdev) > > { > > struct qcom_smd_rpm *rpm; > > - int ret; > > > > rpm = devm_kzalloc(&rpdev->dev, sizeof(*rpm), GFP_KERNEL); > > if (!rpm) > > @@ -210,24 +207,7 @@ static int qcom_smd_rpm_probe(struct rpmsg_device *rpdev) > > rpm->rpm_channel = rpdev->ept; > > dev_set_drvdata(&rpdev->dev, rpm); > > > > - rpm->icc = platform_device_register_data(&rpdev->dev, "icc_smd_rpm", -1, > > - NULL, 0); > > - if (IS_ERR(rpm->icc)) > > - return PTR_ERR(rpm->icc); > > - > > - ret = of_platform_populate(rpdev->dev.of_node, NULL, NULL, &rpdev->dev); > > - if (ret) > > - platform_device_unregister(rpm->icc); > > - > > - return ret; > > -} > > - > > -static void qcom_smd_rpm_remove(struct rpmsg_device *rpdev) > > -{ > > - struct qcom_smd_rpm *rpm = dev_get_drvdata(&rpdev->dev); > > - > > - platform_device_unregister(rpm->icc); > > - of_platform_depopulate(&rpdev->dev); > > + return devm_of_platform_populate(&rpdev->dev); > > } > > > > static const struct of_device_id qcom_smd_rpm_of_match[] = { > > @@ -256,7 +236,6 @@ MODULE_DEVICE_TABLE(of, qcom_smd_rpm_of_match); > > > > static struct rpmsg_driver qcom_smd_rpm_driver = { > > .probe = qcom_smd_rpm_probe, > > - .remove = qcom_smd_rpm_remove, > This reaches over the removal of the icc registration, the depopulate > call should stay. > I switched the of_platform_populate() to devm_of_platform_populate(), that's why the remove callback is no longer necessary. It's a bit hidden, perhaps it would be enough to add to the commit message: "While at it, switch the remaining of_platform_populate() call to the devm variant and remove the remove callback." Or maybe it should be split into two patches. Thanks, Stephan