From patchwork Mon Mar 6 07:56:31 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 13160598 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 609ECC761A6 for ; Mon, 6 Mar 2023 07:58:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229907AbjCFH6S (ORCPT ); Mon, 6 Mar 2023 02:58:18 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53324 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229744AbjCFH5j (ORCPT ); Mon, 6 Mar 2023 02:57:39 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 122D61CACA; Sun, 5 Mar 2023 23:57:38 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 9E51B60C20; Mon, 6 Mar 2023 07:57:37 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5638FC433A7; Mon, 6 Mar 2023 07:57:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1678089456; bh=c1W/TkN9vDAtIN9NXAe0tdm9B9W8KbajL+RP2x8pc+A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eCaEM2VLx2XY83l08L7XDRRuZ7u94AqS2q2qlBBsoAdhi8pxZGgTC274s4FympNSG RFctAR2TV1Y/o8GwG5h/k+KJNTPjIPY1GOZsffOJQe+Hm/UtsKGOhnoCCrwQGsdKMc vl0WfelGIfvBT5MCZS2V7DP2+ffv0l2Ig9ZW/WMkp1Y8Ai/rpoQBbzNz4coQceScTn IMFEQA5ffWcANiHIJzAeAzI0PcQrGLM1bXRk9300YLNa52rFG0ZQ5mEzzMQ7V3F9T1 1eW2Xzx2yxIJDDrUyShgxqdzUm2GYkrgfWXgzFTpxTsrY1zFUaRZyga8/lhBikINKQ gS8TRjVbHLbSQ== Received: from johan by xi.lan with local (Exim 4.94.2) (envelope-from ) id 1pZ5jb-0000hx-UP; Mon, 06 Mar 2023 08:58:15 +0100 From: Johan Hovold To: Georgi Djakov Cc: "Shawn Guo" , "Sascha Hauer" , "Pengutronix Kernel Team" , "Fabio Estevam" , "NXP Linux Team" , "Andy Gross" , "Bjorn Andersson" , "Konrad Dybcio" , "Sylwester Nawrocki" , =?utf-8?b?QXJ0dXIgxZp3aWdv?= =?utf-8?b?xYQ=?= , "Krzysztof Kozlowski" , "Alim Akhtar" , "Thierry Reding" , "Jonathan Hunter" , linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-samsung-soc@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, Johan Hovold , stable@vger.kernel.org Subject: [PATCH v2 03/23] interconnect: fix provider registration API Date: Mon, 6 Mar 2023 08:56:31 +0100 Message-Id: <20230306075651.2449-4-johan+linaro@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230306075651.2449-1-johan+linaro@kernel.org> References: <20230306075651.2449-1-johan+linaro@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org The current interconnect provider interface is inherently racy as providers are expected to be added before being fully initialised. Specifically, nodes are currently not added and the provider data is not initialised until after registering the provider which can cause racing DT lookups to fail. Add a new provider API which will be used to fix up the interconnect drivers. The old API is reimplemented using the new interface and will be removed once all drivers have been fixed. Fixes: 11f1ceca7031 ("interconnect: Add generic on-chip interconnect API") Fixes: 87e3031b6fbd ("interconnect: Allow endpoints translation via DT") Cc: stable@vger.kernel.org # 5.1 Reviewed-by: Konrad Dybcio Signed-off-by: Johan Hovold Tested-by: Luca Ceresoli --- drivers/interconnect/core.c | 52 +++++++++++++++++++-------- include/linux/interconnect-provider.h | 12 +++++++ 2 files changed, 50 insertions(+), 14 deletions(-) diff --git a/drivers/interconnect/core.c b/drivers/interconnect/core.c index cabb6f5df83e..7a24c1444ace 100644 --- a/drivers/interconnect/core.c +++ b/drivers/interconnect/core.c @@ -1033,44 +1033,68 @@ int icc_nodes_remove(struct icc_provider *provider) EXPORT_SYMBOL_GPL(icc_nodes_remove); /** - * icc_provider_add() - add a new interconnect provider - * @provider: the interconnect provider that will be added into topology + * icc_provider_init() - initialize a new interconnect provider + * @provider: the interconnect provider to initialize + * + * Must be called before adding nodes to the provider. + */ +void icc_provider_init(struct icc_provider *provider) +{ + WARN_ON(!provider->set); + + INIT_LIST_HEAD(&provider->nodes); +} +EXPORT_SYMBOL_GPL(icc_provider_init); + +/** + * icc_provider_register() - register a new interconnect provider + * @provider: the interconnect provider to register * * Return: 0 on success, or an error code otherwise */ -int icc_provider_add(struct icc_provider *provider) +int icc_provider_register(struct icc_provider *provider) { - if (WARN_ON(!provider->set)) - return -EINVAL; if (WARN_ON(!provider->xlate && !provider->xlate_extended)) return -EINVAL; mutex_lock(&icc_lock); - - INIT_LIST_HEAD(&provider->nodes); list_add_tail(&provider->provider_list, &icc_providers); - mutex_unlock(&icc_lock); - dev_dbg(provider->dev, "interconnect provider added to topology\n"); + dev_dbg(provider->dev, "interconnect provider registered\n"); return 0; } -EXPORT_SYMBOL_GPL(icc_provider_add); +EXPORT_SYMBOL_GPL(icc_provider_register); /** - * icc_provider_del() - delete previously added interconnect provider - * @provider: the interconnect provider that will be removed from topology + * icc_provider_deregister() - deregister an interconnect provider + * @provider: the interconnect provider to deregister */ -void icc_provider_del(struct icc_provider *provider) +void icc_provider_deregister(struct icc_provider *provider) { mutex_lock(&icc_lock); WARN_ON(provider->users); - WARN_ON(!list_empty(&provider->nodes)); list_del(&provider->provider_list); mutex_unlock(&icc_lock); } +EXPORT_SYMBOL_GPL(icc_provider_deregister); + +int icc_provider_add(struct icc_provider *provider) +{ + icc_provider_init(provider); + + return icc_provider_register(provider); +} +EXPORT_SYMBOL_GPL(icc_provider_add); + +void icc_provider_del(struct icc_provider *provider) +{ + WARN_ON(!list_empty(&provider->nodes)); + + icc_provider_deregister(provider); +} EXPORT_SYMBOL_GPL(icc_provider_del); static const struct of_device_id __maybe_unused ignore_list[] = { diff --git a/include/linux/interconnect-provider.h b/include/linux/interconnect-provider.h index cd5c5a27557f..d12cd18aab3f 100644 --- a/include/linux/interconnect-provider.h +++ b/include/linux/interconnect-provider.h @@ -122,6 +122,9 @@ int icc_link_destroy(struct icc_node *src, struct icc_node *dst); void icc_node_add(struct icc_node *node, struct icc_provider *provider); void icc_node_del(struct icc_node *node); int icc_nodes_remove(struct icc_provider *provider); +void icc_provider_init(struct icc_provider *provider); +int icc_provider_register(struct icc_provider *provider); +void icc_provider_deregister(struct icc_provider *provider); int icc_provider_add(struct icc_provider *provider); void icc_provider_del(struct icc_provider *provider); struct icc_node_data *of_icc_get_from_provider(struct of_phandle_args *spec); @@ -167,6 +170,15 @@ static inline int icc_nodes_remove(struct icc_provider *provider) return -ENOTSUPP; } +static inline void icc_provider_init(struct icc_provider *provider) { } + +static inline int icc_provider_register(struct icc_provider *provider) +{ + return -ENOTSUPP; +} + +static inline void icc_provider_deregister(struct icc_provider *provider) { } + static inline int icc_provider_add(struct icc_provider *provider) { return -ENOTSUPP;