From nobody Sat Apr 11 02:20:54 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6E070C25B08 for ; Wed, 17 Aug 2022 17:28:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240142AbiHQR2U (ORCPT ); Wed, 17 Aug 2022 13:28:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47172 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241106AbiHQR2A (ORCPT ); Wed, 17 Aug 2022 13:28:00 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 84FA0A1D24 for ; Wed, 17 Aug 2022 10:27:58 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 2BD711063; Wed, 17 Aug 2022 10:27:59 -0700 (PDT) Received: from e120937-lin.home (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9159A3F66F; Wed, 17 Aug 2022 10:27:57 -0700 (PDT) From: Cristian Marussi To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: sudeep.holla@arm.com, cristian.marussi@arm.com Subject: [PATCH 6/6] [RFC] firmware: arm_scmi: Add SCMI PM driver remove routine Date: Wed, 17 Aug 2022 18:27:31 +0100 Message-Id: <20220817172731.1185305-7-cristian.marussi@arm.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220817172731.1185305-1-cristian.marussi@arm.com> References: <20220817172731.1185305-1-cristian.marussi@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Currently, when removing the SCMI PM driver not all the resources registered with GenPD subsystem are currently properly de-registered. As a side effect of this after a driver unload/load cycle you get a splat with a few warnings like this: debugfs: Directory 'BIG_CPU0' with parent 'pm_genpd' already present! debugfs: Directory 'BIG_CPU1' with parent 'pm_genpd' already present! debugfs: Directory 'LITTLE_CPU0' with parent 'pm_genpd' already present! debugfs: Directory 'LITTLE_CPU1' with parent 'pm_genpd' already present! debugfs: Directory 'LITTLE_CPU2' with parent 'pm_genpd' already present! debugfs: Directory 'LITTLE_CPU3' with parent 'pm_genpd' already present! debugfs: Directory 'BIG_SSTOP' with parent 'pm_genpd' already present! debugfs: Directory 'LITTLE_SSTOP' with parent 'pm_genpd' already present! debugfs: Directory 'DBGSYS' with parent 'pm_genpd' already present! debugfs: Directory 'GPUTOP' with parent 'pm_genpd' already present! Add a proper scmi_pm_domain_remove callback to the driver in order to take care of all the needed cleanups not handled already by devres. Signed-off-by: Cristian Marussi --- The patch is marked as RFC since this solution can be controversial: what about any 3rd party consumer of the above unregistered genpd domain ? Should we even ever allow a PM driver like to be unloaded ? --- drivers/firmware/arm_scmi/scmi_pm_domain.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/drivers/firmware/arm_scmi/scmi_pm_domain.c b/drivers/firmware/= arm_scmi/scmi_pm_domain.c index 581d34c95769..4e27c3d66a83 100644 --- a/drivers/firmware/arm_scmi/scmi_pm_domain.c +++ b/drivers/firmware/arm_scmi/scmi_pm_domain.c @@ -138,9 +138,28 @@ static int scmi_pm_domain_probe(struct scmi_device *sd= ev) scmi_pd_data->domains =3D domains; scmi_pd_data->num_domains =3D num_domains; =20 + dev_set_drvdata(dev, scmi_pd_data); + return of_genpd_add_provider_onecell(np, scmi_pd_data); } =20 +static void scmi_pm_domain_remove(struct scmi_device *sdev) +{ + int i; + struct genpd_onecell_data *scmi_pd_data; + struct device *dev =3D &sdev->dev; + struct device_node *np =3D dev->of_node; + + of_genpd_del_provider(np); + + scmi_pd_data =3D dev_get_drvdata(dev); + for (i =3D 0; i < scmi_pd_data->num_domains; i++) { + if (!scmi_pd_data->domains[i]) + continue; + pm_genpd_remove(scmi_pd_data->domains[i]); + } +} + static const struct scmi_device_id scmi_id_table[] =3D { { SCMI_PROTOCOL_POWER, "genpd" }, { }, @@ -150,6 +169,7 @@ MODULE_DEVICE_TABLE(scmi, scmi_id_table); static struct scmi_driver scmi_power_domain_driver =3D { .name =3D "scmi-power-domain", .probe =3D scmi_pm_domain_probe, + .remove =3D scmi_pm_domain_remove, .id_table =3D scmi_id_table, }; module_scmi_driver(scmi_power_domain_driver); --=20 2.32.0