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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2C484C982EA for ; Sun, 20 Sep 2026 09:21:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=c+PFA3o7u4LP9UbfBorEmDqajAgXqdamQ9sCfBZKl9Y=; b=XNfETR+bQABk1f2hCWtXi4sX2p NOJnL24M+rQf3zw7QyUN9kv7d6p0J50OYbXdb42PHajn0S9OIF8HKmXr3l3kbuHEsguDMizbWNn0g m562blH4pSZ55hZe2jzxxb7aeDoqRrhw1q3IzWC25qbaVW0bgqEkE3IzYP+TPi5Qu610bXBeegmSe UiRv+7+DoUqPBAcd3ffJ+SVEL8QDe+O6gDCIjXWgqFdrcRTSSAMxf+zp+LE/feGaJmEwIopaQWFrD V68YY95OXBSLO1yHQgCDExQtlFxRGtxM4nqe+SY09XOtGDZzpK6+PiFFmoVrDRWsPCVBTWqkdhoDO gvm111IA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x8Djo-0000000HA3I-1X6Q; Sun, 20 Sep 2026 09:21:32 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x8DjT-0000000H9j7-2SsO for linux-arm-kernel@lists.infradead.org; Sun, 20 Sep 2026 09:21:14 +0000 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 C20B71650; Sun, 20 Sep 2026 02:21:06 -0700 (PDT) Received: from pluto.fritz.box (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6F4F13F59E; Sun, 20 Sep 2026 02:21:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1789896070; bh=t9wyyeFMtxTXqDtnieZJaEnVceYHrygP7s5U8LrdN4U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LAfe+EYKuJjFImL9E5GNvvtEJzJICNNETd3BtNGHQ996sgFy8dWc/5pNwTQ4HmSU2 E6DePx9z6IdxoYs2IjUl5thX3i5XIKGbvrwG7xqc+r+PtYZlRBZ4kT082CwW4uhfnV +LSMaNSWiRGW24wvu23rzgCXgSJTd3iQs+oKN+jM= From: Cristian Marussi To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, arm-scmi@vger.kernel.org, linux-doc@vger.kernel.org Cc: sudeep.holla@kernel.org, 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, d-gole@ti.com, jic23@kernel.org, elif.topuz@arm.com, lukasz.luba@arm.com, philip.radford@arm.com, david@kernel.org, souvik.chakravarty@arm.com, leitao@kernel.org, kas@kernel.org, puranjay@kernel.org, usama.arif@linux.dev, kernel-team@meta.com, Cristian Marussi Subject: [PATCH v12 14/25] firmware: arm_scmi: Add Telemetry generation counter event Date: Sun, 20 Sep 2026 10:19:17 +0100 Message-ID: <20260920091928.2014972-15-cristian.marussi@arm.com> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260920091928.2014972-1-cristian.marussi@arm.com> References: <20260920091928.2014972-1-cristian.marussi@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260920_022111_743382_5FA117A4 X-CRM114-Status: GOOD ( 18.92 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Add a per-instance generation counter to track configuration changes which uses the common telemetry events framework. Signed-off-by: Cristian Marussi --- v11 -->v12 - reviewed generation counter update logic v6 --> v7 - use new Generic event mechanism based on EventFD instead of WaitQ v5 --> v6 - add relese semantic to the atomic set of the generation counter - use new eventfd_ctx common event logic --- drivers/firmware/arm_scmi/telemetry.c | 48 ++++++++++++++++++++++++++- include/linux/scmi_protocol.h | 6 ++-- 2 files changed, 51 insertions(+), 3 deletions(-) diff --git a/drivers/firmware/arm_scmi/telemetry.c b/drivers/firmware/arm_scmi/telemetry.c index c76409083160..ada4838d2351 100644 --- a/drivers/firmware/arm_scmi/telemetry.c +++ b/drivers/firmware/arm_scmi/telemetry.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include #include @@ -26,6 +27,7 @@ #include #include #include +#include #include "protocols.h" #include "notify.h" @@ -35,6 +37,7 @@ /* Updated only after ALL the mandatory features for that version are merged */ #define SCMI_PROTOCOL_SUPPORTED_VERSION 0x10000 +#define SCMI_TLM_GENERATION_ONE (SCMI_TLM_GENERATION_INVALID + 1U) #define SCMI_TLM_TDCF_MAX_RETRIES 5 #define SCMI_TLM_DE_IMPL_NUM_DWORDS 4 @@ -719,6 +722,37 @@ scmi_telemetry_tde_cache_lookup(struct telemetry_de *tde, return 0; } +static inline void __scmi_telemetry_generation_set(struct telemetry_info *ti, + unsigned int new) +{ + int ret; + + atomic_set_release(&ti->info.generation, new); + + ret = scmi_telemetry_event_signal(ti, SCMI_TLM_EVT_GENERATION); + if (ret) + dev_warn_once(ti->ph->dev, + "Could NOT signal telemetry event %d\n", + SCMI_TLM_EVT_GENERATION); +} + +static inline void scmi_telemetry_generation_update(struct telemetry_info *ti) +{ + unsigned int next; + + lockdep_assert_held(&ti->config_mtx); + + /* Wrap around skipping invalid generation 0 */ + next = (atomic_read(&ti->info.generation) + 1) ?: SCMI_TLM_GENERATION_ONE; + + __scmi_telemetry_generation_set(ti, next); +} + +static inline void scmi_telemetry_generation_reset(struct telemetry_info *ti) +{ + __scmi_telemetry_generation_set(ti, SCMI_TLM_GENERATION_ONE); +} + struct scmi_tlm_de_priv { struct telemetry_info *ti; void *next; @@ -2734,6 +2768,8 @@ static int __scmi_telemetry_state_set(const struct scmi_protocol_handle *ph, tstamp_enabled_state, *tstamp); + /* A local change can have an impact anyway */ + scmi_telemetry_generation_update(ti); return 0; } @@ -2766,11 +2802,13 @@ static int __scmi_telemetry_state_set(const struct scmi_protocol_handle *ph, ret = ph->xops->do_xfer(ph, t); if (!ret) { ret = scmi_telemetry_state_set_resp_process(ti, obj, resp, is_group); - if (!ret) + if (!ret) { /* Update cached state on success */ scmi_telemetry_state_cache_update(ti, enable, enabled_state, tstamp, tstamp_enabled_state, grp, de); + scmi_telemetry_generation_update(ti); + } } ph->xops->xfer_put(ph, t); @@ -2959,6 +2997,9 @@ scmi_telemetry_collection_configure(const struct scmi_protocol_handle *ph, ph->xops->xfer_put(ph, t); + if (!ret) + scmi_telemetry_generation_update(ti); + return ret; } @@ -3473,6 +3514,9 @@ static int scmi_telemetry_reset(const struct scmi_protocol_handle *ph) struct telemetry_info *ti = ph->get_priv(ph); scmi_telemetry_local_resources_reset(ti); + /* Reset generation now that server has been reset */ + scmi_telemetry_generation_reset(ti); + /* NO need to lookup the initial state we have just reset all */ } @@ -3994,6 +4038,8 @@ static int scmi_telemetry_instance_init(struct telemetry_info *ti) for (int i = 0; i < SCMI_TLM_EVT_MAX; i++) INIT_LIST_HEAD(&ti->events[i]); mutex_init(&ti->events_mtx); + /* Generation counter init */ + atomic_set(&ti->info.generation, SCMI_TLM_GENERATION_ONE); atomic_set(&ti->des_enabled[ENA_STATE], 0); atomic_set(&ti->des_enabled[ENA_TSTAMP], 0); mutex_init(&ti->des_enabled_mtx); diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h index b4b3e95547ba..56b098bc472d 100644 --- a/include/linux/scmi_protocol.h +++ b/include/linux/scmi_protocol.h @@ -891,6 +891,7 @@ enum scmi_telemetry_collection { SCMI_TLM_SINGLE_READ, }; +#define SCMI_TLM_GENERATION_INVALID 0U #define SCMI_TLM_GRP_INVALID 0xFFFFFFFF struct scmi_telemetry_intervals { @@ -986,6 +987,7 @@ struct scmi_telemetry_info { bool enabled; bool notif_enabled; enum scmi_telemetry_collection current_mode; + atomic_t generation; }; struct scmi_telemetry_de_sample { @@ -996,7 +998,7 @@ struct scmi_telemetry_de_sample { }; enum scmi_telemetry_event { - SCMI_TLM_EVT_DUMMY, + SCMI_TLM_EVT_GENERATION, SCMI_TLM_EVT_MAX, }; @@ -1022,11 +1024,11 @@ enum scmi_telemetry_event { * the ones belonging to a specific group when provided. * This causes an immediate update platform-side of all the * enabled DEs. - * @reset: reset configuration and telemetry data. * @event_subscribe: subscribe to the specified event @type using the provided * @eventfd_ctx. * @event_unsubscribe: unsubscribe to the specified event @type the previously * registered @eventfd_ctx. + * @reset: reset configuration and telemetry data. */ struct scmi_telemetry_proto_ops { const struct scmi_telemetry_info __must_check *(*info_get) -- 2.54.0