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=-6.8 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,URIBL_BLOCKED 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 27F7FC433E0 for ; Wed, 20 May 2020 16:12:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E6C7420671 for ; Wed, 20 May 2020 16:12:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="X25mO4FM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726650AbgETQM2 (ORCPT ); Wed, 20 May 2020 12:12:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44078 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726443AbgETQM2 (ORCPT ); Wed, 20 May 2020 12:12:28 -0400 Received: from mail-vs1-xe41.google.com (mail-vs1-xe41.google.com [IPv6:2607:f8b0:4864:20::e41]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C5CEFC061A0E for ; Wed, 20 May 2020 09:12:27 -0700 (PDT) Received: by mail-vs1-xe41.google.com with SMTP id u2so2109897vsi.13 for ; Wed, 20 May 2020 09:12:27 -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=YtrzLXGtxgRWkzlUqxtu97QqoZy64rwr9++B/m+w0bM=; b=X25mO4FMVFWX9bD4sVjVdh6jjataSoBgWwqq7lzOARIYBhnm3zLBKkY9JTZx8EgSAq 7aNz2eLhfh/m6xOFl/fobLsZ13/d6V+wop2isk9rpCP8RcOuf4jdok4ulS0GcLLQZUEo C1lcgXy8FoEivSrEG/HgFDWOBZMcFP6W5NVZTCxhgANHntp1XotjhrIrY2P7nfrzF4fN LwOgsH8MJnBlq04yRlUbgjwD4xZYwek9WGtbq1xSh9QR0L39c0XpsJrK6rMCxW2a3a2h 7RtUli0zxYZuQs687PvV6H5aqXpzoWGfHHzu8h7dsB/f0Ef+DRb1Gsj1MtMRt8cflgVU 4G3g== 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=YtrzLXGtxgRWkzlUqxtu97QqoZy64rwr9++B/m+w0bM=; b=ct81haVUIidy+yjOTxTb7lhatQRFQS8IcTBqGqmDePEkxMT9kqH8SFv61qVIyvIqnj 7pWwGhp4DkKij1VhixJiR8dWasjY60KVPXJGeflD1EPtcFJHjPsUwY1bGBJpTK0oMoDi wuIM4H2TfKimSFn6nJ99rI4l17ajEJpKfe1ZZnlu/1asDgYVJTzBt37d6URdOPsEDdwv DSnGFuyB8pav+xcQPHCJ3xzc9Qjk8lX2gB6od48NiPbLYnTUDZmaZua6EE9AfzY+V9AV uf8UVnJEyMh54hSZZwPigRX0HpDI+LD6cVcQus5EugjTxm9r+OGz/rO1YUAzDG1ttBeK 19HQ== X-Gm-Message-State: AOAM531R557oIb3bNwqkUpPHSy1R/LkEwTRZ/5O/ruFOEa6D1pa8i+OM Y8TLD+em75fPuDCmdamKd+GlM/9U/INnzP8op+H4bg== X-Google-Smtp-Source: ABdhPJyUxYSmAfttYuzTfbgRH+uY3/B82jtNFyWpV0GDSdLZj6mIIT72znl6jOaKVWRHsC01UabEC6lC4aZ+E7zxU9U= X-Received: by 2002:a05:6102:5d6:: with SMTP id v22mr3741710vsf.191.1589991146916; Wed, 20 May 2020 09:12:26 -0700 (PDT) MIME-Version: 1.0 References: <20200519152445.6922-1-ulf.hansson@linaro.org> In-Reply-To: From: Ulf Hansson Date: Wed, 20 May 2020 18:11:50 +0200 Message-ID: Subject: Re: [PATCH 2/2] mmc: tmio: Make sure the PM domain is 'started' while probing To: Geert Uytterhoeven Cc: Linux MMC List , Masahiro Yamada , Wolfram Sang , Ulrich Hecht , Simon Horman , Niklas Soderlund , Geert Uytterhoeven Content-Type: text/plain; charset="UTF-8" Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org On Wed, 20 May 2020 at 17:57, Geert Uytterhoeven wrote: > > Hi Ulf, > > On Tue, May 19, 2020 at 5:24 PM Ulf Hansson wrote: > > If the tmio device is attached to a genpd (PM domain), that genpd may have > > ->start|stop() callback assigned to it. To make sure the device is > > accessible during ->probe(), genpd's ->start() callback must be invoked, > > which is currently managed by tmio_mmc_host_probe(). However, it's likely > > that may be too late for some cases, as registers may be read and written > > way before that point. > > > > To fix the behaviour, let's move the call to dev_pm_domain_start() from > > tmio_mmc_host_probe() into those clients that needs it. From discussions at > > linux-mmc mailing list, it turned out that it should be sufficient to do > > this for the SDHI renesas variants, hence the call is move to > > renesas_sdhi_probe(). > > > > Signed-off-by: Ulf Hansson > > --- > > drivers/mmc/host/renesas_sdhi_core.c | 3 +++ > > drivers/mmc/host/tmio_mmc_core.c | 2 -- > > 2 files changed, 3 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/mmc/host/renesas_sdhi_core.c b/drivers/mmc/host/renesas_sdhi_core.c > > index ff72b381a6b3..dcba9ad35dd1 100644 > > --- a/drivers/mmc/host/renesas_sdhi_core.c > > +++ b/drivers/mmc/host/renesas_sdhi_core.c > > @@ -24,6 +24,7 @@ > > #include > > #include > > #include > > +#include > > #include > > #include > > #include > > @@ -905,6 +906,8 @@ int renesas_sdhi_probe(struct platform_device *pdev, > > /* All SDHI have SDIO status bits which must be 1 */ > > mmc_data->flags |= TMIO_MMC_SDIO_STATUS_SETBITS; > > > > + dev_pm_domain_start(&pdev->dev); > > + > > > I have debug prints at the top of genpd_stop_dev(): > > pr_info("==== %s/%s: stop\n", genpd->name, dev_name(dev)); > > and genpd_start_dev(): > > pr_info("==== %s/%s: start\n", genpd->name, dev_name(dev)); > > On Koelsch (R-Car M2-W), the three SDHI devices are started twice: > > PM: ==== always-on/ee100000.sd: start > PM: ==== always-on/ee140000.sd: start > PM: ==== always-on/ee160000.sd: start > PM: ==== always-on/ee100000.sd: start > PM: ==== always-on/ee140000.sd: start > PM: ==== always-on/ee160000.sd: start > > The first time, the probe is deferred, because the regulator needed in > tmio_mmc_init_ocr() hasn't been instantiated yet. The SDHI device is > detached from the PM domain, but not stopped. > Interestingly, I see no clock imbalances afterwards. That's because genpd's->detach_dev() callback is invoked at the "deferred probe" case. In your case this ends up calling pm_clk_destroy(). Thus the clock gets disabled and unprepared correctly. > > On R-Car Gen3, R-Mobile A1, and RZ/A systems, they are started once, > as expected. > > On R-Mobile APE6 and SH-Mobile AG5, one device is stopped and started > again: > > PM: ==== a3sp/ee100000.sd: start > PM: ==== a3sp/ee120000.sd: start > PM: ==== a3sp/ee120000.sd: stop > PM: ==== a3sp/ee120000.sd: start > > But here no probe deferral is involved. > Just Runtime PM kicking in, I guess. Yep, and that's okay, right? > > > ret = renesas_sdhi_clk_enable(host); > > if (ret) > > goto efree; > > diff --git a/drivers/mmc/host/tmio_mmc_core.c b/drivers/mmc/host/tmio_mmc_core.c > > index ba301fb7656b..d7fde57c78c1 100644 > > --- a/drivers/mmc/host/tmio_mmc_core.c > > +++ b/drivers/mmc/host/tmio_mmc_core.c > > @@ -39,7 +39,6 @@ > > #include > > #include > > #include > > -#include > > #include > > #include > > #include > > @@ -1192,7 +1191,6 @@ int tmio_mmc_host_probe(struct tmio_mmc_host *_host) > > /* See if we also get DMA */ > > tmio_mmc_request_dma(_host, pdata); > > > > - dev_pm_domain_start(&pdev->dev); > > Before, the issue on probe deferral didn't happen, as the device was only > started after the regulator was found. I am not sure there is an issue or did I miss something? > > > pm_runtime_get_noresume(&pdev->dev); > > pm_runtime_set_active(&pdev->dev); > > pm_runtime_set_autosuspend_delay(&pdev->dev, 50); > > Gr{oetje,eeting}s, > > Geert Thanks a lot for testing and sharing results! Very much appreciated! Kind regards Uffe