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=-17.2 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,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 22588C433ED for ; Wed, 7 Apr 2021 05:05:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CD26C613CC for ; Wed, 7 Apr 2021 05:05:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244465AbhDGFF6 (ORCPT ); Wed, 7 Apr 2021 01:05:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36496 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348549AbhDGFF6 (ORCPT ); Wed, 7 Apr 2021 01:05:58 -0400 Received: from mail-pf1-x436.google.com (mail-pf1-x436.google.com [IPv6:2607:f8b0:4864:20::436]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 55F90C06174A for ; Tue, 6 Apr 2021 22:05:48 -0700 (PDT) Received: by mail-pf1-x436.google.com with SMTP id l123so10523448pfl.8 for ; Tue, 06 Apr 2021 22:05:48 -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=v1EbD4K5+ZpWVviiRiexwAVWwPlInM5vPeGVWeHHASY=; b=YBp9fyCEC8aVk/aQfLyQqYsm0CSq3/xmquVD+YjKYRMRWbPdk83zBZ/XEVmFdPr8fm VIEdxoQ+lvgeoto4KE41aChQ/+a/RKijez0cM774a4CzCAVeVKEWOAhNKj61UOc/b217 vY0h9lLREemGIzzPLGKOP8FX2q4aUQKOQuWlUUy2xXnFQkG2IFdW7dgb9FRgRFcpZCg0 tVNE3a2ZYVbsQ4GH0aZ3PK06MfIkDp2qD4bk4txYrU7cEhZE/AmunZtiBxKthQSxGL5r 8fCDhBx4gjiZ49PsJZhAjTBZVpnYxHbdJ84SBgWl+nU/cmelDO1zdiCim0FUXFXz5U0X wZTw== 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=v1EbD4K5+ZpWVviiRiexwAVWwPlInM5vPeGVWeHHASY=; b=GM+yOM0T0aTiSgQYFnOG6682ehQL+eTzl9uOH6Hxq54wlWO0+7+ZKIbDIGFelhL+4c YCkk/38WQr0gubY9665TNfL6WvGPFEr4hqbQ7jRZoIwHuwlcrrYq/P5CwbzxCLmeDnmD G2fi+u6p+uZnOvXJGpZ4oCQdjqzPWhPeQlQ1nrl8uBQxUk6+MBmcg+hiV4fz2VPjvzo7 eP1lkSRrW17MCVk5UCGEYSyQwqWmWsh2bbGVXSRoGArYvpO8gvEC3zkR+tEztxyn6YJK 7q7GRlTooJugb4sUuZkmXRNUYpyCXoOswJzij72OkrB8E8WFZCfSlrudK3ifOsE6kyvp /R+g== X-Gm-Message-State: AOAM531XTzIpg0WU7L9L/AqZTKeY/NCOtuYtHPHuIprdK6QIk2szLsTk FXNxXbFMVrckelEYPEF5y00rSUHiglF4 X-Google-Smtp-Source: ABdhPJw+1h2A346rNL1K65aCM5og/W9kT11xWu3+Tvdm1KmrZhLjLPGDTaFYqn2N7wOVqKFfcaq2GQ== X-Received: by 2002:a62:bd03:0:b029:21d:b680:db15 with SMTP id a3-20020a62bd030000b029021db680db15mr1411811pff.25.1617771947787; Tue, 06 Apr 2021 22:05:47 -0700 (PDT) Received: from work ([103.77.37.180]) by smtp.gmail.com with ESMTPSA id f2sm20353479pfq.129.2021.04.06.22.05.45 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Tue, 06 Apr 2021 22:05:46 -0700 (PDT) Date: Wed, 7 Apr 2021 10:35:44 +0530 From: Manivannan Sadhasivam To: Loic Poulain Cc: hemantk@codeaurora.org, bbhatt@codeaurora.org, linux-arm-msm@vger.kernel.org Subject: Re: [PATCH v2 1/2] bus: mhi: core: Fix MHI runtime_pm behavior Message-ID: <20210407050544.GB8675@work> References: <1617700315-12492-1-git-send-email-loic.poulain@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1617700315-12492-1-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 Tue, Apr 06, 2021 at 11:11:54AM +0200, 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. > > Signed-off-by: Loic Poulain Reviewed-by: Manivannan Sadhasivam Thanks, Mani > --- > v2: mhi_reset_data_chan: move put under existing DMA_TO_DEVICE if block > > drivers/bus/mhi/core/main.c | 21 ++++++++++++++++----- > 1 file changed, 16 insertions(+), 5 deletions(-) > > diff --git a/drivers/bus/mhi/core/main.c b/drivers/bus/mhi/core/main.c > index c780234..6e72239 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); > > @@ -1416,8 +1424,11 @@ static void mhi_reset_data_chan(struct mhi_controller *mhi_cntrl, > while (tre_ring->rp != tre_ring->wp) { > struct mhi_buf_info *buf_info = buf_ring->rp; > > - 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); > + } > > if (!buf_info->pre_mapped) > mhi_cntrl->unmap_single(mhi_cntrl, buf_info); > -- > 2.7.4 >