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=-17.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 C6AFAC433ED for ; Wed, 31 Mar 2021 17:14:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9CB6261026 for ; Wed, 31 Mar 2021 17:14:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233757AbhCaRN3 (ORCPT ); Wed, 31 Mar 2021 13:13:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52970 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229787AbhCaRM5 (ORCPT ); Wed, 31 Mar 2021 13:12:57 -0400 Received: from mail-pl1-x62e.google.com (mail-pl1-x62e.google.com [IPv6:2607:f8b0:4864:20::62e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4052DC061574 for ; Wed, 31 Mar 2021 10:12:57 -0700 (PDT) Received: by mail-pl1-x62e.google.com with SMTP id ay2so8235303plb.3 for ; Wed, 31 Mar 2021 10:12:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=Z3+8hPiPx8bVU1yZj+P8PIPaGQrYTj5Jj/muY7V4UIE=; b=dP2bCxd8Mdqq7IhxLvaNx4gtCmCvbrlHjPgixIOW9DWgwCHkwTpBjzEGF5kT0buDql 28wd77NeXfL4hTCqNQpiU8rErRBQktGg9bDqjLFvEnteLxQp3RVoHnpMj1bljVoUGdqC YNBg0brvuaL6nBkMjEQ8eb3WceetM2pwhkmc2l4LXkaQAPGwHaFEdZO34osBYl+ayEBy Ht7FYVWNaexK16G0zSidpi4CQIhWUgLUrXchrK8iMkJ/8kBweSgixxBy923hZGOk/nBy ABRpRCA9YC7Th2m10ds4Fp9sGLSa8kZuHfvAlwGicQNsjMrUQBr+STc4i7J8HcPKcEdv nzvw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=Z3+8hPiPx8bVU1yZj+P8PIPaGQrYTj5Jj/muY7V4UIE=; b=Lo0beTwJB9SncCulYKiMfsT+PSCuut+2Hml9FCMgo/KHQJrEsWnSlNRAj3S/oJ2egw 5TSuzFjAHDg9vH1pbG3U3vK53B9+q1zvJ+ETiCVUYfQWkI7DVdJs080bCzv/q5d7xfgd 9k7DIj7ffTNNbf9Pw8E0wsAXq6COqacU1xV6r2qaAsUr/3w530MherkyfpOYcSGUe971 m+osL63c+n6kVkE3QKFcDH1GhJLNxanI29Bvbs/iw2TgYXDsPdtKi0BG9VHKykn0vzIU ulMaANoZlSvVN+uWAUkD56iLVADNP+1Q797XUYXwnqccF22jxLSiUfHBw1Tl8pYolGoz OsOQ== X-Gm-Message-State: AOAM533mAFFhAWqt/lmb9fSbbzidOusAgnslGuOxzzx/KbH57ZvvvdeV EKwSbqzcl19HjvPLJs23Phci+20HhoIBg78= X-Google-Smtp-Source: ABdhPJz0aBRJkwwRX/UfUf6WwDVw8VXL79bbtE5huXUJr/RCUgrrsZhneu0oUeEAILGMPaohYoWzUw== X-Received: by 2002:a17:902:a587:b029:e7:347d:4872 with SMTP id az7-20020a170902a587b02900e7347d4872mr4240614plb.2.1617210776614; Wed, 31 Mar 2021 10:12:56 -0700 (PDT) Received: from work ([103.77.37.129]) by smtp.gmail.com with ESMTPSA id o18sm2694802pji.10.2021.03.31.10.12.54 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Wed, 31 Mar 2021 10:12:55 -0700 (PDT) Date: Wed, 31 Mar 2021 22:42:52 +0530 From: Manivannan Sadhasivam To: Loic Poulain Cc: hemantk@codeaurora.org, linux-arm-msm@vger.kernel.org Subject: Re: [PATCH 1/2] bus: mhi: core: Fix MHI runtime_pm behavior Message-ID: <20210331171252.GK15610@work> References: <1614963744-25962-1-git-send-email-loic.poulain@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1614963744-25962-1-git-send-email-loic.poulain@linaro.org> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On Fri, Mar 05, 2021 at 06:02:23PM +0100, Loic Poulain wrote: > This change ensures that PM reference is always get during packet > queueing and released either after queuing completion (RX) or once > the buffer has been consumed (TX). This guarantees proper update for > underlying MHI controller runtime status (e.g. last_busy timestamp) > and prevents suspend to be triggered while TX packets are flying, > or before we completed update of the RX ring. > Any reason why you didn't wait for RX completion also? Thanks, Mani > Signed-off-by: Loic Poulain > --- > drivers/bus/mhi/core/main.c | 20 ++++++++++++++++---- > 1 file changed, 16 insertions(+), 4 deletions(-) > > diff --git a/drivers/bus/mhi/core/main.c b/drivers/bus/mhi/core/main.c > index c780234..16b9640 100644 > --- a/drivers/bus/mhi/core/main.c > +++ b/drivers/bus/mhi/core/main.c > @@ -584,8 +584,11 @@ static int parse_xfer_event(struct mhi_controller *mhi_cntrl, > /* notify client */ > mhi_chan->xfer_cb(mhi_chan->mhi_dev, &result); > > - if (mhi_chan->dir == DMA_TO_DEVICE) > + if (mhi_chan->dir == DMA_TO_DEVICE) { > atomic_dec(&mhi_cntrl->pending_pkts); > + /* Release the reference got from mhi_queue() */ > + mhi_cntrl->runtime_put(mhi_cntrl); > + } > > /* > * Recycle the buffer if buffer is pre-allocated, > @@ -1021,9 +1024,11 @@ static int mhi_queue(struct mhi_device *mhi_dev, struct mhi_buf_info *buf_info, > if (unlikely(ret)) > goto exit_unlock; > > - /* trigger M3 exit if necessary */ > - if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state)) > - mhi_trigger_resume(mhi_cntrl); > + /* Packet is queued, take a usage ref to exit M3 if necessary > + * for host->device buffer, balanced put is done on buffer completion > + * for device->host buffer, balanced put is after ringing the DB > + */ > + mhi_cntrl->runtime_get(mhi_cntrl); > > /* Assert dev_wake (to exit/prevent M1/M2)*/ > mhi_cntrl->wake_toggle(mhi_cntrl); > @@ -1034,6 +1039,9 @@ static int mhi_queue(struct mhi_device *mhi_dev, struct mhi_buf_info *buf_info, > if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl))) > mhi_ring_chan_db(mhi_cntrl, mhi_chan); > > + if (dir == DMA_FROM_DEVICE) > + mhi_cntrl->runtime_put(mhi_cntrl); > + > exit_unlock: > read_unlock_irqrestore(&mhi_cntrl->pm_lock, flags); > > @@ -1431,6 +1439,10 @@ static void mhi_reset_data_chan(struct mhi_controller *mhi_cntrl, > result.buf_addr = buf_info->cb_buf; > mhi_chan->xfer_cb(mhi_chan->mhi_dev, &result); > } > + > + /* Release the reference got from mhi_queue() */ > + if (mhi_chan->dir == DMA_TO_DEVICE) > + mhi_cntrl->runtime_put(mhi_cntrl); > } > } > > -- > 2.7.4 >