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=-6.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 A18B1C3F2C6 for ; Mon, 9 Mar 2020 17:34:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6C45F2253D for ; Mon, 9 Mar 2020 17:34:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="BMwB3RSt" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727414AbgCIRe4 (ORCPT ); Mon, 9 Mar 2020 13:34:56 -0400 Received: from mail-il1-f193.google.com ([209.85.166.193]:46370 "EHLO mail-il1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727257AbgCIRe4 (ORCPT ); Mon, 9 Mar 2020 13:34:56 -0400 Received: by mail-il1-f193.google.com with SMTP id e8so9416165ilc.13 for ; Mon, 09 Mar 2020 10:34:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=ApATodv8Am9ujhMEtBHZPqW70inNY25NHpEVeLaEJS8=; b=BMwB3RStSKIJiDZ+rW1tapXVJFXrpECngEU4yoCfBahr42ryFItvJr9PHV2F+7H2ql a8lqk8hqOd4jtPkjOefQtqDub0bgKYOf6QwAnJmDwRqU7ESBf5GnqwpZRtKxfXMfjpK0 AhNQvI5+pyifRJNG02Hdt5GTurHg+dcJnniFq6ma9gwvL8cCK+p25JlS5QnhAiarswax HnD8Avp5zBg0RVK6kw6cIof6SrjxjjiTZNl+yrulZZq39MCbChr3OZgXBSKgfh0wqDld HYcyeSjeBDok9FSrbExR3DEFA8idA84jnAcW+2IRuEawpzf0lQ5shuJzMc+PDEtFD+iY w2hw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=ApATodv8Am9ujhMEtBHZPqW70inNY25NHpEVeLaEJS8=; b=YplkiKzlBTknBMS6oS1cW/q0CXwkJ7Fb3c4YskjN59emVs49vRUeiOigR/oCZDOFJg UpHkatbtPxVcOuYMibMZ3Mm2qn5H6zGdCioPV0r/BRyqVcOb6/mC++uyEt/MosMl7wAD z/Qt76XUjlYE2unheoaUysPvUdxvTWqf03R6gpD6RywcWK+wtpOAXLgqymozdN1Ovwm5 QUtqP2B5rBg/1pFobeUp4gx85iSk7GA3eTkKU1azMcaGd0uxgN/aP5If36cMorrK4nrW L+vH/RpA4y3luzlFnF5/nf+LhnDZr3eoSw8nQtP/UQAcCgYVR0SUV6MTUhBCzRlNZDqO up6g== X-Gm-Message-State: ANhLgQ1RLwAPVWoDGNS1OmtQPhFQHLadGNQJj/3LwQ2S0A0hmOXAcyp+ TITOEawc6ZNe8wixcF+mENzVdTNNOEHuED4sazkWyg== X-Google-Smtp-Source: ADFU+vsWUJUgLPEpHpmSHEuF+s3xAiAj1cYQfkg//rVgbBCo9iYjZ+Tk1b+JfpGL8M5a27rDabsK1Y0BpfiMQYafmlY= X-Received: by 2002:a92:8586:: with SMTP id f128mr5107434ilh.50.1583775294490; Mon, 09 Mar 2020 10:34:54 -0700 (PDT) MIME-Version: 1.0 References: <1582167465-2549-1-git-send-email-sidgup@codeaurora.org> <1582167465-2549-7-git-send-email-sidgup@codeaurora.org> <20200227215940.GC20116@xps15> <1a615fcd5a5c435d1d8babe8d5c3f8c3@codeaurora.org> <20200228183832.GA23026@xps15> <050a8613cd00a84678b4478ef3387465@codeaurora.org> In-Reply-To: <050a8613cd00a84678b4478ef3387465@codeaurora.org> From: Mathieu Poirier Date: Mon, 9 Mar 2020 11:34:43 -0600 Message-ID: Subject: Re: [PATCH 6/6] remoteproc: qcom: Add notification types to SSR To: Rishabh Bhatnagar Cc: Ohad Ben-Cohen , tsoni@codeaurora.org, linux-arm-msm , linux-remoteproc , Linux Kernel Mailing List , Bjorn Andersson , Andy Gross , Siddharth Gupta , psodagud@codeaurora.org, linux-arm-kernel , linux-remoteproc-owner@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 3 Mar 2020 at 16:30, wrote: > > On 2020-03-03 10:05, Mathieu Poirier wrote: > > On Mon, 2 Mar 2020 at 13:54, wrote: > >> > >> On 2020-02-28 10:38, Mathieu Poirier wrote: > >> > On Thu, Feb 27, 2020 at 04:00:21PM -0800, rishabhb@codeaurora.org > >> > wrote: > >> >> On 2020-02-27 13:59, Mathieu Poirier wrote: > >> >> > On Wed, Feb 19, 2020 at 06:57:45PM -0800, Siddharth Gupta wrote: > >> >> > > The SSR subdevice only adds callback for the unprepare event. Add > >> >> > > callbacks > >> >> > > for unprepare, start and prepare events. The client driver for a > >> >> > > particular > >> >> > > remoteproc might be interested in knowing the status of the remoteproc > >> >> > > while undergoing SSR, not just when the remoteproc has finished > >> >> > > shutting > >> >> > > down. > >> >> > > > >> >> > > Signed-off-by: Siddharth Gupta > >> >> > > --- > >> >> > > drivers/remoteproc/qcom_common.c | 39 > >> >> > > +++++++++++++++++++++++++++++++++++---- > >> >> > > include/linux/remoteproc.h | 15 +++++++++++++++ > >> >> > > 2 files changed, 50 insertions(+), 4 deletions(-) > >> >> > > > >> >> > > diff --git a/drivers/remoteproc/qcom_common.c > >> >> > > b/drivers/remoteproc/qcom_common.c > >> >> > > index 6714f27..6f04a5b 100644 > >> >> > > --- a/drivers/remoteproc/qcom_common.c > >> >> > > +++ b/drivers/remoteproc/qcom_common.c > >> >> > > @@ -183,9 +183,9 @@ EXPORT_SYMBOL_GPL(qcom_remove_smd_subdev); > >> >> > > * > >> >> > > * Returns pointer to srcu notifier head on success, ERR_PTR on > >> >> > > failure. > >> >> > > * > >> >> > > - * This registers the @notify function as handler for restart > >> >> > > notifications. As > >> >> > > - * remote processors are stopped this function will be called, with > >> >> > > the rproc > >> >> > > - * pointer passed as a parameter. > >> >> > > + * This registers the @notify function as handler for > >> >> > > powerup/shutdown > >> >> > > + * notifications. This function will be invoked inside the > >> >> > > callbacks registered > >> >> > > + * for the ssr subdevice, with the rproc pointer passed as a > >> >> > > parameter. > >> >> > > */ > >> >> > > void *qcom_register_ssr_notifier(struct rproc *rproc, struct > >> >> > > notifier_block *nb) > >> >> > > { > >> >> > > @@ -227,11 +227,39 @@ int qcom_unregister_ssr_notifier(void *notify, > >> >> > > struct notifier_block *nb) > >> >> > > } > >> >> > > EXPORT_SYMBOL_GPL(qcom_unregister_ssr_notifier); > >> >> > > > >> >> > > +static int ssr_notify_prepare(struct rproc_subdev *subdev) > >> >> > > +{ > >> >> > > + struct qcom_rproc_ssr *ssr = to_ssr_subdev(subdev); > >> >> > > + > >> >> > > + srcu_notifier_call_chain(ssr->rproc_notif_list, > >> >> > > + RPROC_BEFORE_POWERUP, (void *)ssr->name); > >> >> > > + return 0; > >> >> > > +} > >> >> > > + > >> >> > > +static int ssr_notify_start(struct rproc_subdev *subdev) > >> >> > > +{ > >> >> > > + struct qcom_rproc_ssr *ssr = to_ssr_subdev(subdev); > >> >> > > + > >> >> > > + srcu_notifier_call_chain(ssr->rproc_notif_list, > >> >> > > + RPROC_AFTER_POWERUP, (void *)ssr->name); > >> >> > > + return 0; > >> >> > > +} > >> >> > > + > >> >> > > +static void ssr_notify_stop(struct rproc_subdev *subdev, bool > >> >> > > crashed) > >> >> > > +{ > >> >> > > + struct qcom_rproc_ssr *ssr = to_ssr_subdev(subdev); > >> >> > > + > >> >> > > + srcu_notifier_call_chain(ssr->rproc_notif_list, > >> >> > > + RPROC_BEFORE_SHUTDOWN, (void *)ssr->name); > >> >> > > +} > >> >> > > + > >> >> > > + > >> >> > > static void ssr_notify_unprepare(struct rproc_subdev *subdev) > >> >> > > { > >> >> > > struct qcom_rproc_ssr *ssr = to_ssr_subdev(subdev); > >> >> > > > >> >> > > - srcu_notifier_call_chain(ssr->rproc_notif_list, 0, (void > >> >> > > *)ssr->name); > >> >> > > + srcu_notifier_call_chain(ssr->rproc_notif_list, > >> >> > > + RPROC_AFTER_SHUTDOWN, (void *)ssr->name); > >> >> > > } > >> >> > > > >> >> > > /** > >> >> > > @@ -248,6 +276,9 @@ void qcom_add_ssr_subdev(struct rproc *rproc, > >> >> > > struct qcom_rproc_ssr *ssr, > >> >> > > { > >> >> > > ssr->name = ssr_name; > >> >> > > ssr->subdev.name = kstrdup("ssr_notifs", GFP_KERNEL); > >> >> > > + ssr->subdev.prepare = ssr_notify_prepare; > >> >> > > + ssr->subdev.start = ssr_notify_start; > >> >> > > + ssr->subdev.stop = ssr_notify_stop; > >> >> > > >> >> > Now that I have a better understanding of what this patchset is doing, I > >> >> > realise > >> >> > my comments in patch 04 won't work. To differentiate the subdevs of an > >> >> > rproc I > >> >> > suggest to wrap them in a generic structure with a type and an enum. > >> >> > That way > >> >> > you can differenciate between subdevices without having to add to the > >> >> > core. > >> >> Ok. I can try that. > >> >> > > >> >> > That being said, I don't understand what patches 5 and 6 are doing... > >> >> > Registering with the global ssr_notifiers allowed to gracefully shutdown > >> >> > all the > >> >> > MCUs in the system when one of them would go down. But now that we are > >> >> > using > >> >> > the notifier on a per MCU, I really don't see why each subdev couldn't > >> >> > implement > >> >> > the right prepare/start/stop functions. > >> >> > > >> >> > Am I missing something here? > >> >> We only want kernel clients to be notified when the Remoteproc they > >> >> are > >> >> interested > >> >> in changes state. For e.g. audio kernel driver should be notified when > >> >> audio > >> >> processor goes down but it does not care about any other remoteproc. > >> >> If you are suggesting that these kernel clients be added as subdevices > >> >> then > >> >> we will end up having many subdevices registered to each remoteproc. > >> >> So we > >> >> implemented a notifier chain per Remoteproc. This keeps the SSR > >> >> notifications as > >> >> the subdevice per remoteproc, and all interested clients can register > >> >> to it. > >> > > >> > It seems like I am missing information... Your are referring to > >> > "kernel > >> > clients" and as such I must assume some drivers that are not part of > >> > the > >> > remoteproc/rpmsg subsystems are calling qcom_register_ssr_notifier(). > >> > I must > >> Yes these are not part of remoteproc framework and they will register > >> for notifications. > >> > also assume these drivers (or that functionality) are not yet upsream > >> > because > >> > all I can see calling qcom_register_ssr_notifier() is > >> > qcom_glink_ssr_probe(). > >> Correct.These are not upstreamed. > > > > Ok, things are starting to make sense. > > > >> > > >> > Speaking of which, what is the role of the qcom_glink_ssr_driver? Is > >> > the glink > >> > device that driver is handling the same as the glink device registed in > >> > adsp_probe() and q6v5_probe()? > >> glink ssr driver will send out notifications to remoteprocs that have > >> opened the > >> "glink_ssr" channel that some subsystem has gone down or booted up. > >> This > >> helps notify > >> neighboring subsystems about change in state of any other subsystem. > > > > I am still looking for an answer to my second question. > Yes its the subdevice of the glink device that is registered in > adsp_probe. > It uses the "glink_ssr" glink channel. Since this is confining events to a single MCU, I was mostly worried about opening the "glink_ssr" channel for nothing but taking a step back and thinking further on this, there might be other purposes for the channel than only receiving notifications of other MCUs in the system going down. Please spin off a new revision of this set and I will take another look. Thanks, Mathieu > > > >> > > >> >> > > >> >> > > >> >> > > ssr->subdev.unprepare = ssr_notify_unprepare; > >> >> > > ssr->rproc_notif_list = kzalloc(sizeof(struct srcu_notifier_head), > >> >> > > GFP_KERNEL); > >> >> > > diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h > >> >> > > index e2f60cc..4be4478 100644 > >> >> > > --- a/include/linux/remoteproc.h > >> >> > > +++ b/include/linux/remoteproc.h > >> >> > > @@ -449,6 +449,21 @@ struct rproc_dump_segment { > >> >> > > }; > >> >> > > > >> >> > > /** > >> >> > > + * enum rproc_notif_type - Different stages of remoteproc > >> >> > > notifications > >> >> > > + * @RPROC_BEFORE_SHUTDOWN: unprepare stage of remoteproc > >> >> > > + * @RPROC_AFTER_SHUTDOWN: stop stage of remoteproc > >> >> > > + * @RPROC_BEFORE_POWERUP: prepare stage of remoteproc > >> >> > > + * @RPROC_AFTER_POWERUP: start stage of remoteproc > >> >> > > + */ > >> >> > > +enum rproc_notif_type { > >> >> > > + RPROC_BEFORE_SHUTDOWN, > >> >> > > + RPROC_AFTER_SHUTDOWN, > >> >> > > + RPROC_BEFORE_POWERUP, > >> >> > > + RPROC_AFTER_POWERUP, > >> >> > > + RPROC_MAX > >> >> > > +}; > >> >> > > + > >> >> > > +/** > >> >> > > * struct rproc - represents a physical remote processor device > >> >> > > * @node: list node of this rproc object > >> >> > > * @domain: iommu domain > >> >> > > -- > >> >> > > Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, > >> >> > > a Linux Foundation Collaborative Project > >> >> > > > >> >> > > _______________________________________________ > >> >> > > linux-arm-kernel mailing list > >> >> > > linux-arm-kernel@lists.infradead.org > >> >> > > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > >> > >> _______________________________________________ > >> linux-arm-kernel mailing list > >> linux-arm-kernel@lists.infradead.org > >> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel