From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 596E53BF69E; Wed, 17 Jun 2026 09:59:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781690373; cv=none; b=Ly9q/ROZF/eSkS+dYs1h5ZaXt/1lVv3hs53uQu8eTCq2n1ALwpiB/simdfCtycIqe8SGZfuCqRVZ9qIuu7NGMZV8qFjW31qZSfwGrSoF+msvmrF2TPnyCN5A1erpmhZAVozEGicOh7k4pS05+SC4fc/F6qJuyDQej8RcRXPNjJU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781690373; c=relaxed/simple; bh=v4PQvJxXL6yAb8eVisl3HMvO3Ev5F2132vGHAZ1Y3G8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VEdSLRD3HkxRVJ1vhKPQiKrQFhy0+QuVDlurMycSlIHlTpsJW6I7104EHalgQhgHYWKTWnKNVtGApUBc1p7/X0U2eSaTpTKapPwXyXns2jBIyaQHC3l67+Lz6QMKhCQ59qXQ4IlLMzrHxowCSzveCTvk9jKlvRGY+Xa25AScl/k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=ocKnKrUN; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="ocKnKrUN" 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 7AB124800; Wed, 17 Jun 2026 02:59:24 -0700 (PDT) Received: from donnerap.manchester.arm.com (donnerap.manchester.arm.com [10.33.8.81]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id CC1E13F915; Wed, 17 Jun 2026 02:59:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1781690369; bh=v4PQvJxXL6yAb8eVisl3HMvO3Ev5F2132vGHAZ1Y3G8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ocKnKrUNbDSGDgA+dgTEXWVBhPgJ7ntsBDPjrnt8OqAIa8r32N4spvPd7My6PyJvx TUxBfqGpcPYMnbZlDMMzfcrE7k6FOTS8URajgVXp6ldMHyNNAvzzeqHVTrDFGOVYvG rVE5k76a00UbE9b6wqoWjPYkuEkvXnNHaUL0XZxY= From: Philip Radford To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, arm-scmi@vger.kernel.org, linux-pm@vger.kernel.org Cc: sudeep.holla@arm.com, james.quinlan@broadcom.com, f.fainelli@gmail.com, vincent.guittot@linaro.org, etienne.carriere@st.com, peng.fan@oss.nxp.com, michal.simek@amd.com, quic_sibis@quicinc.com, dan.carpenter@linaro.org, d-gole@ti.com, souvik.chakravarty@arm.com, Philip Radford Subject: [PATCH v7 01/13] powercap: Add enable disable control-type Date: Wed, 17 Jun 2026 10:58:58 +0100 Message-ID: <20260617095910.1963578-2-philip.radford@arm.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260617095910.1963578-1-philip.radford@arm.com> References: <20260617095910.1963578-1-philip.radford@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Add functionality to disable or enable the Powercap control-type by writing directly into sys/class/powercap/arm-scmi/enabled. Signed-off-by: Philip Radford --- drivers/powercap/arm_scmi_powercap.c | 155 ++++++++++++++++++++++++++- 1 file changed, 154 insertions(+), 1 deletion(-) diff --git a/drivers/powercap/arm_scmi_powercap.c b/drivers/powercap/arm_scmi_powercap.c index ab66e9a3b1e2..e33829d5c551 100644 --- a/drivers/powercap/arm_scmi_powercap.c +++ b/drivers/powercap/arm_scmi_powercap.c @@ -33,13 +33,151 @@ struct scmi_powercap_zone { struct scmi_powercap_root { unsigned int num_zones; + bool enabled; + struct list_head node; struct scmi_powercap_zone *spzones; struct list_head *registered_zones; struct list_head scmi_zones; }; +static LIST_HEAD(scmi_powercap_roots); +static DEFINE_MUTEX(scmi_powercap_roots_lock); + static struct powercap_control_type *scmi_top_pcntrl; +static bool scmi_powercap_is_control_type_child(const struct scmi_powercap_zone *spz) +{ + return spz->registered && !spz->invalid && + spz->info->parent_id == SCMI_POWERCAP_ROOT_ZONE_ID; +} + +static int +scmi_powercap_read_root_children_enable_state(struct scmi_powercap_root *pr, bool *mode) +{ + struct scmi_powercap_zone *spz; + bool enabled; + int i, ret; + + *mode = true; + + for (i = 0; i < pr->num_zones; i++) { + spz = &pr->spzones[i]; + + if (!scmi_powercap_is_control_type_child(spz)) + continue; + + ret = powercap_ops->cap_enable_get(spz->ph, spz->info->id, &enabled); + if (ret) + return ret; + + if (!enabled) { + *mode = false; + return 0; + } + } + + return 0; +} + +static int +scmi_powercap_set_root_children_enable_state(struct scmi_powercap_root *pr, bool enable) +{ + struct scmi_powercap_zone *spz; + bool *prev_state; + int i, ret; + + prev_state = kcalloc(pr->num_zones, sizeof(*prev_state), GFP_KERNEL); + if (!prev_state) + return -ENOMEM; + + for (i = 0; i < pr->num_zones; i++) { + spz = &pr->spzones[i]; + + if (!scmi_powercap_is_control_type_child(spz)) + continue; + + ret = powercap_ops->cap_enable_get(spz->ph, spz->info->id, + &prev_state[i]); + + if (ret) + goto revert; + + if (prev_state[i] == enable) + continue; + + ret = powercap_ops->cap_enable_set(spz->ph, spz->info->id, enable); + if (ret) + goto revert; + } + + pr->enabled = enable; + kfree(prev_state); + return 0; + +revert: + while (--i >= 0) { + spz = &pr->spzones[i]; + + if (!scmi_powercap_is_control_type_child(spz)) + continue; + if (!spz->info->powercap_cap_config) + continue; + if (prev_state[i] == enable) + continue; + + powercap_ops->cap_enable_set(spz->ph, spz->info->id, prev_state[i]); + } + + kfree(prev_state); + return ret; +} + +static int +scmi_powercap_control_type_set_enable(struct powercap_control_type *pct, bool mode) +{ + struct scmi_powercap_root *pr; + int ret = 0; + + mutex_lock(&scmi_powercap_roots_lock); + list_for_each_entry(pr, &scmi_powercap_roots, node) { + ret = scmi_powercap_set_root_children_enable_state(pr, mode); + if (ret) + break; + } + mutex_unlock(&scmi_powercap_roots_lock); + + return ret; +} + +static int +scmi_powercap_control_type_get_enable(struct powercap_control_type *pct, bool *mode) +{ + struct scmi_powercap_root *pr; + int ret = 0; + + *mode = true; + + mutex_lock(&scmi_powercap_roots_lock); + list_for_each_entry(pr, &scmi_powercap_roots, node) { + ret = scmi_powercap_read_root_children_enable_state(pr, &pr->enabled); + + if (ret) + break; + if (!pr->enabled) { + *mode = false; + break; + } + } + mutex_unlock(&scmi_powercap_roots_lock); + + return ret; +} + +static const struct powercap_control_type_ops scmi_powercap_control_type_ops = { + .set_enable = scmi_powercap_control_type_set_enable, + .get_enable = scmi_powercap_control_type_get_enable, +}; + static int scmi_powercap_zone_release(struct powercap_zone *pz) { return 0; @@ -495,6 +633,16 @@ static int scmi_powercap_probe(struct scmi_device *sdev) if (ret) return ret; + INIT_LIST_HEAD(&pr->node); + + ret = scmi_powercap_read_root_children_enable_state(pr, &pr->enabled); + if (ret) + return ret; + + mutex_lock(&scmi_powercap_roots_lock); + list_add_tail(&pr->node, &scmi_powercap_roots); + mutex_unlock(&scmi_powercap_roots_lock); + dev_set_drvdata(dev, pr); return ret; @@ -505,6 +653,10 @@ static void scmi_powercap_remove(struct scmi_device *sdev) struct device *dev = &sdev->dev; struct scmi_powercap_root *pr = dev_get_drvdata(dev); + mutex_lock(&scmi_powercap_roots_lock); + list_del(&pr->node); + mutex_unlock(&scmi_powercap_roots_lock); + scmi_powercap_unregister_all_zones(pr); } @@ -525,7 +677,8 @@ static int __init scmi_powercap_init(void) { int ret; - scmi_top_pcntrl = powercap_register_control_type(NULL, "arm-scmi", NULL); + scmi_top_pcntrl = powercap_register_control_type(NULL, "arm-scmi", + &scmi_powercap_control_type_ops); if (IS_ERR(scmi_top_pcntrl)) return PTR_ERR(scmi_top_pcntrl); -- 2.47.3