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=-15.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 440C9C433FE for ; Wed, 9 Dec 2020 19:49:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0CE652337F for ; Wed, 9 Dec 2020 19:49:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387994AbgLITtT (ORCPT ); Wed, 9 Dec 2020 14:49:19 -0500 Received: from m43-15.mailgun.net ([69.72.43.15]:42798 "EHLO m43-15.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733111AbgLITtK (ORCPT ); Wed, 9 Dec 2020 14:49:10 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1607543323; h=Content-Transfer-Encoding: Content-Type: In-Reply-To: MIME-Version: Date: Message-ID: From: References: Cc: To: Subject: Sender; bh=BDsqBtsR+tJlXw/x5FPrFdURybZlwARsyz23aASsQNI=; b=Q+UdnsqxtsE9NgXbzDQLQ7EzPDxoigS6USwHAGrvkQIh3dilHEqi6lwYuZ1b6zcdgRiUfA4G dih/V7Frm3Bl6iJaMIsbr8NDXNoI3WG3JRHUyni5B6dt/Daf6nPLTRGpRupJFph6ty07/SCQ ns4MKOA2yDEiF9wtknAJ4qRGExg= X-Mailgun-Sending-Ip: 69.72.43.15 X-Mailgun-Sid: WyI1MzIzYiIsICJsaW51eC1hcm0tbXNtQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n04.prod.us-east-1.postgun.com with SMTP id 5fd129f8c62570206cbbf4d2 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Wed, 09 Dec 2020 19:48:08 GMT Sender: jhugo=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id DCAECC43463; Wed, 9 Dec 2020 19:48:07 +0000 (UTC) Received: from [10.226.59.216] (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: jhugo) by smtp.codeaurora.org (Postfix) with ESMTPSA id A2874C433C6; Wed, 9 Dec 2020 19:48:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org A2874C433C6 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=jhugo@codeaurora.org Subject: Re: [PATCH] mhi: use irq_flags if client driver configures it To: Hemant Kumar , Carl Huang , manivannan.sadhasivam@linaro.org Cc: linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org References: <20201208035500.30581-1-cjhuang@codeaurora.org> From: Jeffrey Hugo Message-ID: Date: Wed, 9 Dec 2020 12:48:05 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.5.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On 12/9/2020 11:34 AM, Hemant Kumar wrote: > > > On 12/7/20 7:55 PM, Carl Huang wrote: >> If client driver has specified the irq_flags, mhi uses this specified >> irq_flags. Otherwise, mhi uses default irq_flags. >> >> The purpose of this change is to support one MSI vector for QCA6390. >> MHI will use one same MSI vector too in this scenario. >> >> In case of one MSI vector, IRQ_NO_BALANCING is needed when irq handler >> is requested. The reason is if irq migration happens, the msi_data may >> change too. However, the msi_data is already programmed to QCA6390 >> hardware during initialization phase. This msi_data inconsistence will >> result in crash in kernel. I'm confused as to how this happens. >> >> Another issue is in case of one MSI vector, IRQF_NO_SUSPEND will trigger >> WARNINGS because QCA6390 wants to disable the IRQ during the suspend. >> >> To avoid above two issues, QCA6390 driver specifies the irq_flags in case >> of one MSI vector when mhi_register_controller is called. Surely this change should be in a series where there is a following change which updates the QCA6390 driver? >> >> Signed-off-by: Carl Huang >> --- >>   drivers/bus/mhi/core/init.c | 9 +++++++-- >>   include/linux/mhi.h         | 1 + >>   2 files changed, 8 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c >> index 0ffdebd..5f74e1e 100644 >> --- a/drivers/bus/mhi/core/init.c >> +++ b/drivers/bus/mhi/core/init.c >> @@ -148,12 +148,17 @@ int mhi_init_irq_setup(struct mhi_controller >> *mhi_cntrl) >>   { >>       struct mhi_event *mhi_event = mhi_cntrl->mhi_event; >>       struct device *dev = &mhi_cntrl->mhi_dev->dev; >> +    unsigned long irq_flags = IRQF_SHARED | IRQF_NO_SUSPEND; >>       int i, ret; >> +    /* if client driver has set irq_flags, use it */ >> +    if (mhi_cntrl->irq_flags) >> +        irq_flags = mhi_cntrl->irq_flags; > Jeff if i remember correctly your use case also have one dedicated irq > line for all the MSIs, just want to confirm if you are fine with this > change ? i was wondering if any input check is required for irq_flags > passed by controller, or responsibility is on controller for any > undesired behavior. Like passing IRQF_SHARED and IRQF_ONESHOT when one > irq line is shared among multiple MSIs. This feels a bit weird to me, but I don't think it'll cause a problem. If we are allowing the controller to specify flags, should they be in a per irq manner? >> + >>       /* Setup BHI_INTVEC IRQ */ >>       ret = request_threaded_irq(mhi_cntrl->irq[0], mhi_intvec_handler, >>                      mhi_intvec_threaded_handler, >> -                   IRQF_SHARED | IRQF_NO_SUSPEND, >> +                   irq_flags, >>                      "bhi", mhi_cntrl); >>       if (ret) >>           return ret; >> @@ -171,7 +176,7 @@ int mhi_init_irq_setup(struct mhi_controller >> *mhi_cntrl) >>           ret = request_irq(mhi_cntrl->irq[mhi_event->irq], >>                     mhi_irq_handler, >> -                  IRQF_SHARED | IRQF_NO_SUSPEND, >> +                  irq_flags, >>                     "mhi", mhi_event); >>           if (ret) { >>               dev_err(dev, "Error requesting irq:%d for ev:%d\n", >> diff --git a/include/linux/mhi.h b/include/linux/mhi.h >> index d4841e5..f039e58 100644 >> --- a/include/linux/mhi.h >> +++ b/include/linux/mhi.h >> @@ -442,6 +442,7 @@ struct mhi_controller { >>       bool fbc_download; >>       bool pre_init; >>       bool wake_set; >> +    unsigned long irq_flags; You don't document this. That gets a NACK from me. >>   }; >>   /** >> > > Thanks, > Hemant > -- Jeffrey Hugo Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.