From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vivek Gautam Subject: Re: [PATCH v12 3/4] iommu/arm-smmu: Add the device_link between masters and smmu Date: Mon, 16 Jul 2018 17:16:31 +0530 Message-ID: <93d16301-4bef-203f-24de-4d010de84b22@codeaurora.org> References: <20180708173413.1965-1-vivek.gautam@codeaurora.org> <20180708173413.1965-4-vivek.gautam@codeaurora.org> <5179668.PHK6S3sxLu@aspire.rjw.lan> <741cc78b-59a7-5289-e42f-1511ebedb15d@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Content-Language: en-US List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: "Rafael J. Wysocki" Cc: Mark Rutland , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , Linux PM , Stephen Boyd , Will Deacon , "Rafael J. Wysocki" , open list , iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, robh+dt , linux-arm-msm , Lukas Wunner , freedreno List-Id: linux-arm-msm@vger.kernel.org On 7/16/2018 2:25 PM, Rafael J. Wysocki wrote: > On Thu, Jul 12, 2018 at 2:41 PM, Vivek Gautam > wrote: >> Hi Rafael, >> >> >> On Wed, Jul 11, 2018 at 4:06 PM, Vivek Gautam >> wrote: >>> Hi Rafael, >>> >>> >>> >>> On 7/11/2018 3:23 PM, Rafael J. Wysocki wrote: >>>> On Sunday, July 8, 2018 7:34:12 PM CEST Vivek Gautam wrote: >>>>> From: Sricharan R >>>>> >>>>> Finally add the device link between the master device and >>>>> smmu, so that the smmu gets runtime enabled/disabled only when the >>>>> master needs it. This is done from add_device callback which gets >>>>> called once when the master is added to the smmu. >>>>> >>>>> Signed-off-by: Sricharan R >>>>> Signed-off-by: Vivek Gautam >>>>> Reviewed-by: Tomasz Figa >>>>> Cc: Rafael J. Wysocki >>>>> Cc: Lukas Wunner >>>>> --- >>>>> >>>>> - Change since v11 >>>>> * Replaced DL_FLAG_AUTOREMOVE flag with DL_FLAG_AUTOREMOVE_SUPPLIER. >>>>> >>>>> drivers/iommu/arm-smmu.c | 12 ++++++++++++ >>>>> 1 file changed, 12 insertions(+) >>>>> >>>>> diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c >>>>> index 09265e206e2d..916cde4954d2 100644 >>>>> --- a/drivers/iommu/arm-smmu.c >>>>> +++ b/drivers/iommu/arm-smmu.c >>>>> @@ -1461,8 +1461,20 @@ static int arm_smmu_add_device(struct device *dev) >>>>> iommu_device_link(&smmu->iommu, dev); >>>>> + if (pm_runtime_enabled(smmu->dev) && >>>> Why does the creation of the link depend on whether or not runtime PM >>>> is enabled for the MMU device? >>> >>> The main purpose of this device link is to handle the runtime PM >>> synchronization >>> between the supplier (iommu) and consumer (client devices, such as >>> GPU/display). >>> Moreover, the runtime pm is conditionally enabled for smmu devices that >>> support >>> such [1]. >> Is there something you would like me to modify in this patch? > Not really, as long as you are sure that it is correct. :-) > > You need to remember, however, that if you add system-wide PM > callbacks to the driver, the ordering between them and the client > device callbacks during system-wide suspend matters as well. Don't > you need the link the ensure the correct system-wide suspend ordering > too? The fact that currently we handle clocks only through runtime pm callbacks, would it be better to call runtime pm put/get in system-wide PM callbacks. This would be same as i mentioned in the other thread. Best regards Vivek > -- > To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in > the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > More majordomo info at http://vger.kernel.org/majordomo-info.html 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 X-Spam-Level: X-Spam-Status: No, score=-0.6 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E4D23ECDFAA for ; Mon, 16 Jul 2018 11:46:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 94AEE20844 for ; Mon, 16 Jul 2018 11:46:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="hkwYLzXh"; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="fm3skR9o" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 94AEE20844 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731196AbeGPMNt (ORCPT ); Mon, 16 Jul 2018 08:13:49 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:42994 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730301AbeGPMNs (ORCPT ); Mon, 16 Jul 2018 08:13:48 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id E8FD7606DB; Mon, 16 Jul 2018 11:46:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1531741603; bh=jI/CjfNc2b+a913AMSyXTFA4nrLp6Jw7Yx2ZSUBlV7s=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=hkwYLzXhn/qk1RMcjYNfdV5+g+7Uy6900Xb3zf9a+4g0E0r4GqhkU9QF6IT8GYPwj SgJVIW+crThVE26vwWqYMNWeRAACYqFd9XA+G58XUbYvg82VxOyaq8uaUSfqXo467z Og7Hzpb/KO7Refxwm6L39k/riltq4Y24oxF3Y+oU= Received: from [10.79.40.153] (blr-bdr-fw-01_globalnat_allzones-outside.qualcomm.com [103.229.18.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: vivek.gautam@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id D0887606DB; Mon, 16 Jul 2018 11:46:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1531741600; bh=jI/CjfNc2b+a913AMSyXTFA4nrLp6Jw7Yx2ZSUBlV7s=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=fm3skR9oqFKy1vzEcvwL8rAvkL73lHeRk50M8ccSiZAG80u2Qfa8/Gn/VKksr59v6 +bg6ywuQl/iYUrzTZ9hW93qH0YZm8c7xnSkO/d87Hz9wJlg2DSwdXEsLP4Yc3hoqFV SfwMbBgTb7UYKXc6sS2rmLUgzrs6TI7+w0vKsTHI= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org D0887606DB Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=vivek.gautam@codeaurora.org Subject: Re: [PATCH v12 3/4] iommu/arm-smmu: Add the device_link between masters and smmu To: "Rafael J. Wysocki" Cc: "Rafael J. Wysocki" , "list@263.net:IOMMU DRIVERS" , Joerg Roedel , joro@8bytes.org, robh+dt , Mark Rutland , Robin Murphy , Will Deacon , "list@263.net:IOMMU DRIVERS" , Joerg Roedel , iommu@lists.linux-foundation.org, "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , open list , Alex Williamson , Rob Clark , Linux PM , freedreno , Stephen Boyd , Tomasz Figa , Sricharan R , Marek Szyprowski , Archit Taneja , linux-arm-msm , Jordan Crouse , Lukas Wunner References: <20180708173413.1965-1-vivek.gautam@codeaurora.org> <20180708173413.1965-4-vivek.gautam@codeaurora.org> <5179668.PHK6S3sxLu@aspire.rjw.lan> <741cc78b-59a7-5289-e42f-1511ebedb15d@codeaurora.org> From: Vivek Gautam Message-ID: <93d16301-4bef-203f-24de-4d010de84b22@codeaurora.org> Date: Mon, 16 Jul 2018 17:16:31 +0530 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7/16/2018 2:25 PM, Rafael J. Wysocki wrote: > On Thu, Jul 12, 2018 at 2:41 PM, Vivek Gautam > wrote: >> Hi Rafael, >> >> >> On Wed, Jul 11, 2018 at 4:06 PM, Vivek Gautam >> wrote: >>> Hi Rafael, >>> >>> >>> >>> On 7/11/2018 3:23 PM, Rafael J. Wysocki wrote: >>>> On Sunday, July 8, 2018 7:34:12 PM CEST Vivek Gautam wrote: >>>>> From: Sricharan R >>>>> >>>>> Finally add the device link between the master device and >>>>> smmu, so that the smmu gets runtime enabled/disabled only when the >>>>> master needs it. This is done from add_device callback which gets >>>>> called once when the master is added to the smmu. >>>>> >>>>> Signed-off-by: Sricharan R >>>>> Signed-off-by: Vivek Gautam >>>>> Reviewed-by: Tomasz Figa >>>>> Cc: Rafael J. Wysocki >>>>> Cc: Lukas Wunner >>>>> --- >>>>> >>>>> - Change since v11 >>>>> * Replaced DL_FLAG_AUTOREMOVE flag with DL_FLAG_AUTOREMOVE_SUPPLIER. >>>>> >>>>> drivers/iommu/arm-smmu.c | 12 ++++++++++++ >>>>> 1 file changed, 12 insertions(+) >>>>> >>>>> diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c >>>>> index 09265e206e2d..916cde4954d2 100644 >>>>> --- a/drivers/iommu/arm-smmu.c >>>>> +++ b/drivers/iommu/arm-smmu.c >>>>> @@ -1461,8 +1461,20 @@ static int arm_smmu_add_device(struct device *dev) >>>>> iommu_device_link(&smmu->iommu, dev); >>>>> + if (pm_runtime_enabled(smmu->dev) && >>>> Why does the creation of the link depend on whether or not runtime PM >>>> is enabled for the MMU device? >>> >>> The main purpose of this device link is to handle the runtime PM >>> synchronization >>> between the supplier (iommu) and consumer (client devices, such as >>> GPU/display). >>> Moreover, the runtime pm is conditionally enabled for smmu devices that >>> support >>> such [1]. >> Is there something you would like me to modify in this patch? > Not really, as long as you are sure that it is correct. :-) > > You need to remember, however, that if you add system-wide PM > callbacks to the driver, the ordering between them and the client > device callbacks during system-wide suspend matters as well. Don't > you need the link the ensure the correct system-wide suspend ordering > too? The fact that currently we handle clocks only through runtime pm callbacks, would it be better to call runtime pm put/get in system-wide PM callbacks. This would be same as i mentioned in the other thread. Best regards Vivek > -- > To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html