Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752290AbdGMOBr (ORCPT ); Thu, 13 Jul 2017 10:01:47 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:46480 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751200AbdGMOBo (ORCPT ); Thu, 13 Jul 2017 10:01:44 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 8B163612BB 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 MIME-Version: 1.0 In-Reply-To: References: <1499333825-7658-1-git-send-email-vivek.gautam@codeaurora.org> <1499333825-7658-4-git-send-email-vivek.gautam@codeaurora.org> <20170712225459.GZ22780@codeaurora.org> <5ee0bacd-e557-a6c4-a897-844fb12ea6ae@codeaurora.org> <4dbc938c-ac88-9bd4-cf00-458008ae24c1@codeaurora.org> From: Vivek Gautam Date: Thu, 13 Jul 2017 19:31:41 +0530 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH V4 3/6] iommu/arm-smmu: Invoke pm_runtime during probe, add/remove device To: Sricharan R , Stephen Boyd , robin.murphy@arm.com, Rob Clark Cc: joro@8bytes.org, "robh+dt" , Mark Rutland , Will Deacon , Marek Szyprowski , iommu@lists.linux-foundation.org, "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" , linux-clk@vger.kernel.org, linux-arm-msm@vger.kernel.org, Stanimir Varbanov , architt@codeaurora.org, "linux-arm-kernel@lists.infradead.org" Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2686 Lines: 78 On Thu, Jul 13, 2017 at 7:27 PM, Vivek Gautam wrote: > On Thu, Jul 13, 2017 at 11:05 AM, Sricharan R wrote: >> Hi Vivek, >> >> On 7/13/2017 10:43 AM, Vivek Gautam wrote: >>> Hi Stephen, >>> >>> >>> On 07/13/2017 04:24 AM, Stephen Boyd wrote: >>>> On 07/06, Vivek Gautam wrote: >>>>> @@ -1231,12 +1237,18 @@ static int arm_smmu_map(struct iommu_domain *domain, unsigned long iova, >>>>> static size_t arm_smmu_unmap(struct iommu_domain *domain, unsigned long iova, >>>>> size_t size) >>>>> { >>>>> - struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops; >>>>> + struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); >>>>> + struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops; >>>>> + size_t ret; >>>>> if (!ops) >>>>> return 0; >>>>> - return ops->unmap(ops, iova, size); >>>>> + pm_runtime_get_sync(smmu_domain->smmu->dev); >>>> Can these map/unmap ops be called from an atomic context? I seem >>>> to recall that being a problem before. >>> >>> That's something which was dropped in the following patch merged in master: >>> 523d7423e21b iommu/arm-smmu: Remove io-pgtable spinlock >>> >>> Looks like we don't need locks here anymore? >> >> Apart from the locking, wonder why a explicit pm_runtime is needed >> from unmap. Somehow looks like some path in the master using that >> should have enabled the pm ? > > Right, the master should have done a runtime_get(), and with > device links the iommu will also resume. > > The master will call the unmap when it is attached to the iommu > and therefore the iommu should be in resume state. > We shouldn't have an unmap without the master attached anyways. > Will investigate this further if we need the pm_runtime() calls > around unmap or not. My apologies. My email client didn't update the thread. So please ignore this comment. > > Best regards > Vivek > >> >> Regards, >> Sricharan >> >> -- >> "QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation >> >> --- >> This email has been checked for viruses by Avast antivirus software. >> https://www.avast.com/antivirus >> >> -- >> 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 > > > > -- > Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, > a Linux Foundation Collaborative Project -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project