From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757187AbcJXFaX (ORCPT ); Mon, 24 Oct 2016 01:30:23 -0400 Received: from mailout2.w1.samsung.com ([210.118.77.12]:18634 "EHLO mailout2.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757132AbcJXFaU (ORCPT ); Mon, 24 Oct 2016 01:30:20 -0400 X-AuditID: cbfec7f5-f79ce6d000004c54-1d-580d9c66d514 Subject: Re: [PATCH v5 7/7] iommu/exynos: Use device dependency links to control runtime pm To: Sricharan , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, linux-samsung-soc@vger.kernel.org Cc: "'Tomeu Vizoso'" , "'Bartlomiej Zolnierkiewicz'" , "'Greg Kroah-Hartman'" , "'Kevin Hilman'" , "'Rafael J. Wysocki'" , "'Tomasz Figa'" , "'Krzysztof Kozlowski'" , "'Inki Dae'" , "'Tobias Jakobi'" , "'Luis R. Rodriguez'" , "'Kukjin Kim'" , "'Mark Brown'" , "'Lukas Wunner'" From: Marek Szyprowski Message-id: <7a69ca4e-e276-1bdc-edf2-b881a91f820a@samsung.com> Date: Mon, 24 Oct 2016 07:30:12 +0200 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-version: 1.0 In-reply-to: <001e01d22d12$d2a4e990$77eebcb0$@codeaurora.org> Content-type: text/plain; charset=utf-8; format=flowed Content-transfer-encoding: 7bit X-Brightmail-Tracker: H4sIAAAAAAAAA02Se0gUURTGuzuzM6M5NU2WJ02LhUAK015wyRIjoSkkpIjEnltOaqnJjkpF f5S5PjZT08pVk6S0aEu3TEzNLLVW09DSDCVXk/XRy15W9DDL3VnB/34f5zvfuR9chuAtSlcm IjpW1ESrI1WUI1lh+tXqdeAiG+xjPL0C39Yblfh8/wCFT10xUjirL5PEhQ98cYblPYEH71gU uK3tFo07qi9SePTMI4T1bbUK/GbYDXdlDiL8tKVdib+dTSFx0o3PSmyoHkM4vaSd8ueFjvQz CqHSXISEqjwzLZQZUinhQcFNWsjuuoaEcRMtlHcmk0J6uQEJo2Uegj65Qhk0PcRxTagYGREv arz99jqGX0/rI2M+zTnyuq6OPoFO8jrkwAC3EjoSGpDMc+FZr5HSIUeG54oRmPRJtCxGEdRo LysmNwYGPtgHVxF0Vt63i2EEVZ/6aatrNrcLCqubbQNn7jqCC91aWzDBlZDwJDWBsroobhno RnQ2Zjk/ONvbQFiZ5BZB7peHtqQ53E54de4lIXtmwc/sXtLKDtxa6C7Nte0S3GoYGtcqZV4A d26OENZjwBUw8PF38kQQMyHcoewhIXcIgHdvC+ytZ8O7xnJa5vmQmlJn75mBIEG7RGY9gtYR VmZfaGh8br81A7Iqcgg5noWUJF5GAcy3A2X3OshvfWl7Mc+lK6C7fl4mWpA3pUzelAJ5UwoU IsKAnMU4KSpMlFYtldRRUlx02NL9h6PK0MTXaxlv/F6Jik2r6xHHIJUT29TuFMwr1fHS0ah6 BAyhcmZ9s9hgng1VHz0mag7v0cRFilI9cmNIlQtbU/hiO8+FqWPFQ6IYI2ompwrGwfUEMgbk H3dxd0kL+OdOHOx5vG1Lhc/lsdZpQV7hseYdwSHCXw/t4rXeHsu33vNM9Ok2HDKt2hDzNaNu YaBX86yfQ/EDPSGbmmb+2u174Md4Yq3ne4cc+lGQ9mppaX970TYdMdQMlo25+zY3mmP/hM4t R2qJfNFXNbzD299oubv+UsQpLxUphauXLSY0kvo/qowJjnYDAAA= X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFmpjleLIzCtJLcpLzFFi42I5/e/4Fd3IObwRBq/2cVtsnLGe1WLqwyds Fs2L17NZTLo/gcViwX5ri/7Hr5ktnm5+zGRx/vwGdovLu+awWXzuPcJoMeP8PiaLF8+lLW5M eMpoceb0JVaLLxM7WCzaVn9gtVi16w+jRd/aS2wOQh6X+3qZPHbcXcLosXPWXXaPTas62Tz2 z13D7jH5xnJGj3/H2D22XG1n8ejbsorR4/MmOY8Z7dtYA7ij3GwyUhNTUosUUvOS81My89Jt lUJD3HQtlBTyEnNTbZUidH1DgpQUyhJzSoE8IwM04OAc4B6spG+X4Jaxsuc+S8F70YoHBw+y NzA2CnUxcnJICJhIPHnyhh3CFpO4cG89WxcjF4eQwBJGiYcP/jJCOM8ZJRqOHACrEhaIlViw 6xQ7SEJEYCWjxPFTe5kgqvqYJK4+vcwM4jALbGSRWLt2PzNIC5uAoUTX2y42EJtXwE5i4r3D YHEWAVWJmR8hxooKxEhcf/YIqkZQ4sfkeywgNqeArcTNdTPB4swCZhJfXh5mhbDlJTavecs8 gVFgFpKWWUjKZiEpW8DIvIpRJLW0ODc9t9hQrzgxt7g0L10vOT93EyMwDWw79nPzDsZLG4MP MQpwMCrx8J64xBMhxJpYVlyZe4hRgoNZSYTXehJvhBBvSmJlVWpRfnxRaU5q8SFGU6AnJjJL iSbnA1NUXkm8oYmhuaWhkbGFhbmRkZI4b8mHK+FCAumJJanZqakFqUUwfUwcnFLAOHg8Z2VB uqJCesavDdF5ojF6QRZXYldPZngRrKiWcLaxtH+p1EvLs/+vxX5emPFNwvSD2aP0xKcbLXuu Pyizb/0rGsxeNSWi2d5IIfRi8WEDKaOJLh9Whvg2no0XaM8Jr49v6HzRe8a6r+rG0lT56z7P 4rYKG+o0zNLcoPPeLJp5+pOXd5yVWIozEg21mIuKEwEL0/6CGQMAAA== X-MTR: 20000000000000000@CPGS X-CMS-MailID: 20161024053014eucas1p1d0e18cabf3ce9dd2e53b4f01baa08dc6 X-Msg-Generator: CA X-Sender-IP: 182.198.249.179 X-Local-Sender: =?UTF-8?B?TWFyZWsgU3p5cHJvd3NraRtTUlBPTC1LZXJuZWwgKFRQKRs=?= =?UTF-8?B?7IK87ISx7KCE7J6QG1NlbmlvciBTb2Z0d2FyZSBFbmdpbmVlcg==?= X-Global-Sender: =?UTF-8?B?TWFyZWsgU3p5cHJvd3NraRtTUlBPTC1LZXJuZWwgKFRQKRtT?= =?UTF-8?B?YW1zdW5nIEVsZWN0cm9uaWNzG1NlbmlvciBTb2Z0d2FyZSBFbmdpbmVlcg==?= X-Sender-Code: =?UTF-8?B?QzEwG0VIURtDMTBDRDAyQ0QwMjczOTI=?= CMS-TYPE: 201P X-HopCount: 7 X-CMS-RootMailID: 20161020072336eucas1p24a2b020f69b6ae1f55e1760e6e0e94f9 X-RootMTR: 20161020072336eucas1p24a2b020f69b6ae1f55e1760e6e0e94f9 References: <1476948173-21093-1-git-send-email-m.szyprowski@samsung.com> <1476948173-21093-8-git-send-email-m.szyprowski@samsung.com> <001e01d22d12$d2a4e990$77eebcb0$@codeaurora.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Sricharan, On 2016-10-23 11:49, Sricharan wrote: > Hi Marek, >> This patch uses recently introduced device dependency links to track the >> runtime pm state of the master's device. This way each SYSMMU controller >> is set to runtime active only when its master's device is active and can >> restore or save its state instead of being activated all the time when >> attached to the given master device. This way SYSMMU controllers no longer >> prevents respective power domains to be turned off when master's device >> is not being used. >> >> Signed-off-by: Marek Szyprowski >> --- >> drivers/iommu/exynos-iommu.c | 16 ++++++++-------- >> 1 file changed, 8 insertions(+), 8 deletions(-) >> >> diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c >> index 5e6d7bbf9b70..59b4f2ce4f5f 100644 >> --- a/drivers/iommu/exynos-iommu.c >> +++ b/drivers/iommu/exynos-iommu.c >> @@ -781,10 +781,6 @@ static void exynos_iommu_detach_device(struct iommu_domain *iommu_domain, >> if (!has_sysmmu(dev) || owner->domain != iommu_domain) >> return; >> >> - list_for_each_entry(data, &owner->controllers, owner_node) { >> - pm_runtime_put_sync(data->sysmmu); >> - } >> - >> mutex_lock(&owner->rpm_lock); >> >> list_for_each_entry(data, &owner->controllers, owner_node) { >> @@ -848,10 +844,6 @@ static int exynos_iommu_attach_device(struct iommu_domain *iommu_domain, >> >> mutex_unlock(&owner->rpm_lock); >> >> - list_for_each_entry(data, &owner->controllers, owner_node) { >> - pm_runtime_get_sync(data->sysmmu); >> - } >> - >> dev_dbg(dev, "%s: Attached IOMMU with pgtable %pa\n", __func__, >> &pagetable); >> >> @@ -1232,6 +1224,14 @@ static int exynos_iommu_of_xlate(struct device *dev, >> >> list_add_tail(&data->owner_node, &owner->controllers); >> data->master = dev; >> + >> + /* >> + * SYSMMU will be runtime activated via device link (dependency) to its >> + * master device, so there are no direct calls to pm_runtime_get/put >> + * in this driver. >> + */ >> + device_link_add(dev, data->sysmmu, DL_FLAG_PM_RUNTIME); >> + > So in the case of master with multiple sids, this would be called multiple times > for the same master ? I don't know what is "multiple sids" case, but if given SYSMMU master device (supplier) has multiple SYSMMU controllers (consumers), then links will be created for each SYSMMU controller. Please note that this code is based on vanilla v4.9-rc1, which calls of_xlate() callback only once for every iommu for given master device. Your IOMMU deferred probe patches change this, but I already posted a fix for Exynos IOMMU driver to handle such case. Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland