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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 72928C433FE for ; Fri, 28 Jan 2022 16:36:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350157AbiA1QgS (ORCPT ); Fri, 28 Jan 2022 11:36:18 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44494 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350161AbiA1QgM (ORCPT ); Fri, 28 Jan 2022 11:36:12 -0500 Received: from mail-wm1-x333.google.com (mail-wm1-x333.google.com [IPv6:2a00:1450:4864:20::333]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 539BBC061748 for ; Fri, 28 Jan 2022 08:36:11 -0800 (PST) Received: by mail-wm1-x333.google.com with SMTP id q141-20020a1ca793000000b00347b48dfb53so4447724wme.0 for ; Fri, 28 Jan 2022 08:36:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=mWsbf9R4m7vHX1+nD6A4itXJcqFKk8EHnq/mwBf0uV8=; b=uPgkGPde5xM3eQ1Nz2vjiUjx6WBVdUeXdeMp2b22vCSdRvwszUd4fp3ojbuZxKxAsi xS02sR2sEvIfsNZ4jkkzAkNwPl07EwGtWKNZ78pw0MqMhQSG3N1+ovhDWmEM8ASurAdi dabg8XryV+J8fmWmqAORe1KkPHfNFppn/WHaG8dpGPt+TFe6b1aJqAntQbFGmJazlXih Wv/JCaWsHfEueIRzfqrP6CmLOxfZM8WV7ps92x8oA4B1oJUhIUdnP+N8r7t5bpB82gXX YpkNtMAd6uImPqg9cwOXHt5M0KIvOtbZYVG2nCunbaFtbUn772g8NkWkmDeNNq+2PVv3 e4YQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=mWsbf9R4m7vHX1+nD6A4itXJcqFKk8EHnq/mwBf0uV8=; b=0Q7NJH5YWSI0uPkyMiuAFkbmhzZ0mCkA8+0aQanmMLbanT7D6jm8sXXR8X9J8DnAHY j31m+SYRXqaOXCsUOGDocIKU2SpXdVORVk7LtXuwt/0D5oLQlDyVV0n55sv0q+V9dGnl aBkT4b91RWRXRMjoB48vz8y5wTqHJhR65njY15obTBa8+cqndIRQoZ9D16Cf94GsOiWk yzGk5tY1flljm612WE336BC+MR2AiS4Gp4U5ao9bqxnAI847Xkhf8b8pl2bXhe9mfYTs SLRrl5rNxmc/NMe6l90YPkGIZMhVZW/4S3KKMoHEcyRpyylUDKIZvTY+DFQdDvvuywR6 ivGQ== X-Gm-Message-State: AOAM5327fC6Luf5VIYYKwiE5QS5zO3qgoxJXLL3T4d/oUXyX9WI2/pDo 4E8+5ZtDLxnAsuq9baOm9R5I1g== X-Google-Smtp-Source: ABdhPJwg5xG2AC8YJbbY5WIk7qBGTRv2ClU2sepL6lMExfayb1RqcGEq3gIF/j2kGBVaD4e/KvHeUA== X-Received: by 2002:a1c:4645:: with SMTP id t66mr16050250wma.39.1643387769744; Fri, 28 Jan 2022 08:36:09 -0800 (PST) Received: from localhost.localdomain ([2a01:e34:ed2f:f020:f39:b962:8b8e:9851]) by smtp.gmail.com with ESMTPSA id m6sm5734745wrw.54.2022.01.28.08.36.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 28 Jan 2022 08:36:07 -0800 (PST) From: Daniel Lezcano To: daniel.lezcano@linaro.org, rjw@rjwysocki.net Cc: heiko@sntech.de, robh@kernel.org, lukasz.luba@arm.com, arnd@linaro.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, Ulf Hansson , "Rafael J. Wysocki" , Daniel Lezcano Subject: [PATCH v8 2/5] powercap/drivers/dtpm: Add hierarchy creation Date: Fri, 28 Jan 2022 17:35:34 +0100 Message-Id: <20220128163537.212248-3-daniel.lezcano@linaro.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220128163537.212248-1-daniel.lezcano@linaro.org> References: <20220128163537.212248-1-daniel.lezcano@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The DTPM framework is available but without a way to configure it. This change provides a way to create a hierarchy of DTPM node where the power consumption reflects the sum of the children's power consumption. It is up to the platform to specify an array of dtpm nodes where each element has a pointer to its parent, except the top most one. The type of the node gives the indication of which initialization callback to call. At this time, we can create a virtual node, where its purpose is to be a parent in the hierarchy, and a DT node where the name describes its path. In order to ensure a nice self-encapsulation, the DTPM subsys array contains a couple of initialization functions, one to setup the DTPM backend and one to initialize it up. With this approach, the DTPM framework has a very few material to export. Signed-off-by: Daniel Lezcano Reviewed-by: Ulf Hansson --- drivers/powercap/Kconfig | 1 + drivers/powercap/dtpm.c | 190 ++++++++++++++++++++++++++++++++++++++- include/linux/dtpm.h | 15 ++++ 3 files changed, 203 insertions(+), 3 deletions(-) diff --git a/drivers/powercap/Kconfig b/drivers/powercap/Kconfig index 8242e8c5ed77..b1ca339957e3 100644 --- a/drivers/powercap/Kconfig +++ b/drivers/powercap/Kconfig @@ -46,6 +46,7 @@ config IDLE_INJECT config DTPM bool "Power capping for Dynamic Thermal Power Management (EXPERIMENTAL)" + depends on OF help This enables support for the power capping for the dynamic thermal power management userspace engine. diff --git a/drivers/powercap/dtpm.c b/drivers/powercap/dtpm.c index 0e5c93443c70..414826a1509b 100644 --- a/drivers/powercap/dtpm.c +++ b/drivers/powercap/dtpm.c @@ -23,6 +23,7 @@ #include #include #include +#include #include "dtpm_subsys.h" @@ -463,14 +464,197 @@ int dtpm_register(const char *name, struct dtpm *dtpm, struct dtpm *parent) return 0; } -static int __init init_dtpm(void) +static struct dtpm *dtpm_setup_virtual(const struct dtpm_node *hierarchy, + struct dtpm *parent) { + struct dtpm *dtpm; + int ret; + + dtpm = kzalloc(sizeof(*dtpm), GFP_KERNEL); + if (!dtpm) + return ERR_PTR(-ENOMEM); + dtpm_init(dtpm, NULL); + + ret = dtpm_register(hierarchy->name, dtpm, parent); + if (ret) { + pr_err("Failed to register dtpm node '%s': %d\n", + hierarchy->name, ret); + kfree(dtpm); + return ERR_PTR(ret); + } + + return dtpm; +} + +static struct dtpm *dtpm_setup_dt(const struct dtpm_node *hierarchy, + struct dtpm *parent) +{ + struct device_node *np; + int i, ret; + + np = of_find_node_by_path(hierarchy->name); + if (!np) { + pr_err("Failed to find '%s'\n", hierarchy->name); + return ERR_PTR(-ENXIO); + } + + for (i = 0; i < ARRAY_SIZE(dtpm_subsys); i++) { + + if (!dtpm_subsys[i]->setup) + continue; + + ret = dtpm_subsys[i]->setup(parent, np); + if (ret) { + pr_err("Failed to setup '%s': %d\n", dtpm_subsys[i]->name, ret); + of_node_put(np); + return ERR_PTR(ret); + } + } + + of_node_put(np); + + /* + * By returning a NULL pointer, we let know the caller there + * is no child for us as we are a leaf of the tree + */ + return NULL; +} + +typedef struct dtpm * (*dtpm_node_callback_t)(const struct dtpm_node *, struct dtpm *); + +dtpm_node_callback_t dtpm_node_callback[] = { + [DTPM_NODE_VIRTUAL] = dtpm_setup_virtual, + [DTPM_NODE_DT] = dtpm_setup_dt, +}; + +static int dtpm_for_each_child(const struct dtpm_node *hierarchy, + const struct dtpm_node *it, struct dtpm *parent) +{ + struct dtpm *dtpm; + int i, ret; + + for (i = 0; hierarchy[i].name; i++) { + + if (hierarchy[i].parent != it) + continue; + + dtpm = dtpm_node_callback[hierarchy[i].type](&hierarchy[i], parent); + + /* + * A NULL pointer means there is no children, hence we + * continue without going deeper in the recursivity. + */ + if (!dtpm) + continue; + + /* + * There are multiple reasons why the callback could + * fail. The generic glue is abstracting the backend + * and therefore it is not possible to report back or + * take a decision based on the error. In any case, + * if this call fails, it is not critical in the + * hierarchy creation, we can assume the underlying + * service is not found, so we continue without this + * branch in the tree but with a warning to log the + * information the node was not created. + */ + if (IS_ERR(dtpm)) { + pr_warn("Failed to create '%s' in the hierarchy\n", + hierarchy[i].name); + continue; + } + + ret = dtpm_for_each_child(hierarchy, &hierarchy[i], dtpm); + if (ret) + return ret; + } + + return 0; +} + +/** + * dtpm_create_hierarchy - Create the dtpm hierarchy + * @hierarchy: An array of struct dtpm_node describing the hierarchy + * + * The function is called by the platform specific code with the + * description of the different node in the hierarchy. It creates the + * tree in the sysfs filesystem under the powercap dtpm entry. + * + * The expected tree has the format: + * + * struct dtpm_node hierarchy[] = { + * [0] { .name = "topmost", type = DTPM_NODE_VIRTUAL }, + * [1] { .name = "package", .type = DTPM_NODE_VIRTUAL, .parent = &hierarchy[0] }, + * [2] { .name = "/cpus/cpu0", .type = DTPM_NODE_DT, .parent = &hierarchy[1] }, + * [3] { .name = "/cpus/cpu1", .type = DTPM_NODE_DT, .parent = &hierarchy[1] }, + * [4] { .name = "/cpus/cpu2", .type = DTPM_NODE_DT, .parent = &hierarchy[1] }, + * [5] { .name = "/cpus/cpu3", .type = DTPM_NODE_DT, .parent = &hierarchy[1] }, + * [6] { } + * }; + * + * The last element is always an empty one and marks the end of the + * array. + * + * Return: zero on success, a negative value in case of error. Errors + * are reported back from the underlying functions. + */ +int dtpm_create_hierarchy(struct of_device_id *dtpm_match_table) +{ + const struct of_device_id *match; + const struct dtpm_node *hierarchy; + struct device_node *np; + int i, ret; + + if (pct) + return -EBUSY; + pct = powercap_register_control_type(NULL, "dtpm", NULL); if (IS_ERR(pct)) { pr_err("Failed to register control type\n"); - return PTR_ERR(pct); + ret = PTR_ERR(pct); + goto out_pct; + } + + ret = -ENODEV; + np = of_find_node_by_path("/"); + if (!np) + goto out_err; + + match = of_match_node(dtpm_match_table, np); + + of_node_put(np); + + if (!match) + goto out_err; + + hierarchy = match->data; + if (!hierarchy) { + ret = -EFAULT; + goto out_err; + } + + ret = dtpm_for_each_child(hierarchy, NULL, NULL); + if (ret) + goto out_err; + + for (i = 0; i < ARRAY_SIZE(dtpm_subsys); i++) { + + if (!dtpm_subsys[i]->init) + continue; + + ret = dtpm_subsys[i]->init(); + if (ret) + pr_info("Failed to initialze '%s': %d", + dtpm_subsys[i]->name, ret); } return 0; + +out_err: + powercap_unregister_control_type(pct); +out_pct: + pct = NULL; + + return ret; } -late_initcall(init_dtpm); +EXPORT_SYMBOL_GPL(dtpm_create_hierarchy); diff --git a/include/linux/dtpm.h b/include/linux/dtpm.h index 506048158a50..f7a25c70dd4c 100644 --- a/include/linux/dtpm.h +++ b/include/linux/dtpm.h @@ -32,9 +32,23 @@ struct dtpm_ops { void (*release)(struct dtpm *); }; +struct device_node; + struct dtpm_subsys_ops { const char *name; int (*init)(void); + int (*setup)(struct dtpm *, struct device_node *); +}; + +enum DTPM_NODE_TYPE { + DTPM_NODE_VIRTUAL = 0, + DTPM_NODE_DT, +}; + +struct dtpm_node { + enum DTPM_NODE_TYPE type; + const char *name; + struct dtpm_node *parent; }; static inline struct dtpm *to_dtpm(struct powercap_zone *zone) @@ -52,4 +66,5 @@ void dtpm_unregister(struct dtpm *dtpm); int dtpm_register(const char *name, struct dtpm *dtpm, struct dtpm *parent); +int dtpm_create_hierarchy(struct of_device_id *dtpm_match_table); #endif -- 2.25.1