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=-15.8 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 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 1F0C6C433EF for ; Thu, 23 Sep 2021 13:16:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0447C61211 for ; Thu, 23 Sep 2021 13:16:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241157AbhIWNS0 (ORCPT ); Thu, 23 Sep 2021 09:18:26 -0400 Received: from smtp-relay-internal-0.canonical.com ([185.125.188.122]:49304 "EHLO smtp-relay-internal-0.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234006AbhIWNSY (ORCPT ); Thu, 23 Sep 2021 09:18:24 -0400 Received: from mail-ed1-f72.google.com (mail-ed1-f72.google.com [209.85.208.72]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by smtp-relay-internal-0.canonical.com (Postfix) with ESMTPS id D79E340198 for ; Thu, 23 Sep 2021 13:16:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=canonical.com; s=20210705; t=1632403011; bh=MKDfgpyx2DLaN+agqTgdGBhC7hPiB158s/GwrS6Ihlc=; h=MIME-Version:References:In-Reply-To:From:Date:Message-ID:Subject: To:Cc:Content-Type; b=ZvGSd9mMmXrMflx0SKK+ZcNh4hzVFVNG02AWKpxAk7qAo40N+A41qCpjW0yiCoAYt IPYSf7wtm0Bs3mvR+WDKC4z4L6RGPSRGy14LmoQjrrWbCk7RFYsKWJAWGdvUIFOGPq lhacJiEGg0Pg8b//mvU9nSH24AAyAtM54Nz2iohHYmImntEX9VyERQpviXE3Q+cUIw 6k/BcbsBi5ZBo6qZZailSSdGI+Js8sovS2660avzPZhu1fx+Kc8mRlzG3mpV+AHAbg b4owXuz/cqv9hUwaliEuO2NN/WLPC6cSl0yEMukaWgkyQMHi0rtkmplIXnBggc2vxZ mx+zItvl5bh9Q== Received: by mail-ed1-f72.google.com with SMTP id m30-20020a50999e000000b003cdd7680c8cso6746837edb.11 for ; Thu, 23 Sep 2021 06:16:51 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=MKDfgpyx2DLaN+agqTgdGBhC7hPiB158s/GwrS6Ihlc=; b=6oZcA7WJN8Z+YgP0c4Cspzsrba0midBTN/UGKBAiMERJh6GHn5RBtJUcO/KmFkXNo7 9thrK/81xTKAQwyjQW9nR9Icarv1TblutnV9Ul2+QBhdtw/LVQCZtz98LtSwvNpL/iv/ Lkutx9J98NUbO4bta5pWXLIPOcBNK1Fy+iqcPdAKnsJu/v8xxo7VaAcAAXPp8/eEwKws BNybAdGYRIPmD1Xxe4+ZSkVpnHfhvD40zqcjcGYGXnp83I9us9JETusRczx69099SiaO H3ly4TkeEaFE6z2k+bL+pcXaqmbRJWs6bmXMkpcgb2xrBG9a2RhYw5BIWH2fsaypoTfr 2mXg== X-Gm-Message-State: AOAM532Pet2mq2rLcLONv1tb1iq6fzFB/bE/DiS1JCdbQQ9yjcz9dFRL umD/159Ge1arB+GTfzE8C7XtERIHs78zTPQRfFdmFm0eSH3/XZLYxDrjaxkw3gr40J9TXtuH18r G/Q8nppOPq9OogPAO069YRmFf6PsBUz1SckA0++lULzPUMR6C3qBEsAFFVw== X-Received: by 2002:a50:9d8e:: with SMTP id w14mr5339879ede.74.1632403011491; Thu, 23 Sep 2021 06:16:51 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyrgje9Xp2OF0gTt6J7JjXIzDOTnJlBJzaVdnqqamjZANbNh5L9aWHVmJ3gxN+QGK8XgB4V/GLiPs1Pgzoii4Q= X-Received: by 2002:a50:9d8e:: with SMTP id w14mr5339856ede.74.1632403011278; Thu, 23 Sep 2021 06:16:51 -0700 (PDT) MIME-Version: 1.0 References: <20210921053356.1705833-1-alexandre.ghiti@canonical.com> <28072b8e-2c32-e67d-19d3-026913c0bc7f@codethink.co.uk> In-Reply-To: From: Alexandre Ghiti Date: Thu, 23 Sep 2021 15:16:40 +0200 Message-ID: Subject: Re: [PATCH] drivers: mfd: da9063: Add restart notifier implementation To: Ben Dooks Cc: Support Opensource , Lee Jones , linux-riscv , "linux-kernel@vger.kernel.org List" Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 21, 2021 at 1:33 PM Alexandre Ghiti wrote: > > On Tue, Sep 21, 2021 at 12:25 PM Ben Dooks wrote: > > > > On 21/09/2021 06:33, Alexandre Ghiti wrote: > > > The SiFive Unmatched board uses the da9063 PMIC for reset: add a restart > > > notifier that will execute a small i2c sequence allowing to reset the > > > board. > > > > > > The original implementation comes from Marcus Comstedt and Anders Montonen > > > (https://forums.sifive.com/t/reboot-command/4721/28). > > > > > > Signed-off-by: Alexandre Ghiti > > > > I've got a couple of comments here, mainly is this the right place > > and has anyone other than you tested. I tried something similar on > > my Unmatched and it just turned the board off. > > Someone else in the thread I mention in the commit log tried it, but > more feedback are welcome :) > > For the Unmatched, this solution will be temporary, the best place > being openSBI which lacks i2c support for now. > But I think this can be used by other boards using this PMIC. > > > > > > --- > > > drivers/mfd/da9063-core.c | 25 +++++++++++++++++++++++++ > > > include/linux/mfd/da9063/core.h | 3 +++ > > > 2 files changed, 28 insertions(+) > > > > > > diff --git a/drivers/mfd/da9063-core.c b/drivers/mfd/da9063-core.c > > > index df407c3afce3..c87b8d611f20 100644 > > > --- a/drivers/mfd/da9063-core.c > > > +++ b/drivers/mfd/da9063-core.c > > > @@ -20,6 +20,7 @@ > > > #include > > > #include > > > #include > > > +#include > > > > > > #include > > > #include > > > @@ -158,6 +159,18 @@ static int da9063_clear_fault_log(struct da9063 *da9063) > > > return ret; > > > } > > > > > > +static int da9063_restart_notify(struct notifier_block *this, > > > + unsigned long mode, void *cmd) > > > +{ > > > + struct da9063 *da9063 = container_of(this, struct da9063, restart_handler); > > > + > > > + regmap_write(da9063->regmap, DA9063_REG_PAGE_CON, 0x00); > > > + regmap_write(da9063->regmap, DA9063_REG_CONTROL_F, 0x04); > > > + regmap_write(da9063->regmap, DA9063_REG_CONTROL_A, 0x68); > > > + > > > + return NOTIFY_DONE; > > > +} > > > + > > > > Firstly, do you also need to force the AUTOBOOT (bit 3, CONTROL_C) > > to ensure the PMIC does restart. > > I tried this too and actually, it seems that the value is read from > OTP at reboot and as it is not set here, it has no effect. > > > > > > int da9063_device_init(struct da9063 *da9063, unsigned int irq) > > > { > > > int ret; > > > @@ -197,6 +210,18 @@ int da9063_device_init(struct da9063 *da9063, unsigned int irq) > > > } > > > } > > > > > > + da9063->restart_handler.notifier_call = da9063_restart_notify; > > > + da9063->restart_handler.priority = 128; > > > + ret = register_restart_handler(&da9063->restart_handler); > > > + if (ret) { > > > + dev_err(da9063->dev, "Failed to register restart handler\n"); > > > + return ret; > > > + } > > > + > > > + devm_add_action(da9063->dev, > > > + (void (*)(void *))unregister_restart_handler, > > > + &da9063->restart_handler); > > > > there's devm_register_reboot_notifier() > > Thanks for that! Actually restart_notifier and reboot_notifier are not the same, see https://elixir.bootlin.com/linux/latest/source/kernel/reboot.c#L72. What we need here is restart_handler. Thanks anyway :) Alex > > > > > > > > + > > > return ret; > > > } > > > > > > diff --git a/include/linux/mfd/da9063/core.h b/include/linux/mfd/da9063/core.h > > > index fa7a43f02f27..1b20c498e340 100644 > > > --- a/include/linux/mfd/da9063/core.h > > > +++ b/include/linux/mfd/da9063/core.h > > > @@ -85,6 +85,9 @@ struct da9063 { > > > int chip_irq; > > > unsigned int irq_base; > > > struct regmap_irq_chip_data *regmap_irq; > > > + > > > + /* Restart */ > > > + struct notifier_block restart_handler; > > > }; > > > > > > int da9063_device_init(struct da9063 *da9063, unsigned int irq); > > > > Note, the watchdog driver for the DA9063 also has a restart method > > although it also does not set the AUTOBOOT bit either. > > > > The best thing is to enable the watchdog driver, the SiFive release > > does not have either the core DA9063 or the watchdog driver for it > > enabled. > > It seems that for the restart implemented here to work, the AUTOBOOT > bit needs to be set in the OTP, which seems not to be the case with > the chip on this board: it's been discussed here > https://www.dialog-semiconductor.com/products/pmics?post_id=10052#tab-support_tab_content > (see the accepted answer). > > Thanks, > > Alex > > > > > -- > > Ben Dooks http://www.codethink.co.uk/ > > Senior Engineer Codethink - Providing Genius > > > > https://www.codethink.co.uk/privacy.html