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 X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7548DC2BA83 for ; Fri, 14 Feb 2020 15:36:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4D7AC24677 for ; Fri, 14 Feb 2020 15:36:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729537AbgBNPg1 (ORCPT ); Fri, 14 Feb 2020 10:36:27 -0500 Received: from foss.arm.com ([217.140.110.172]:34708 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729260AbgBNPg0 (ORCPT ); Fri, 14 Feb 2020 10:36:26 -0500 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 8962F328; Fri, 14 Feb 2020 07:36:25 -0800 (PST) Received: from e120937-lin.cambridge.arm.com (e120937-lin.cambridge.arm.com [10.1.197.50]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 884EA3F68E; Fri, 14 Feb 2020 07:36:24 -0800 (PST) From: Cristian Marussi To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: sudeep.holla@arm.com, lukasz.luba@arm.com, james.quinlan@broadcom.com, Jonathan.Cameron@Huawei.com, cristian.marussi@arm.com Subject: [RFC PATCH v2 00/13] SCMI Notifications Core Support Date: Fri, 14 Feb 2020 15:35:22 +0000 Message-Id: <20200214153535.32046-1-cristian.marussi@arm.com> X-Mailer: git-send-email 2.17.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi all, this series wants to introduce SCMI Notification Support, built on top of the standard Kernel notification chain subsystem. At initialization time each SCMI Protocol takes care to register with the new SCMI notification core the set of its own events which it intends to support. Using a possibly proposed API in include/linux/scmi_protocol.h (not finalized though, NO EXPORTs_) a Kernel user can register its own notifier_t callback (via a notifier_block as usual) against any registered event as identified by the tuple: (proto_id, event_id, src_id) where src_id represents a generic source identifier which is protocol dependent like domain_id, performance_id, sensor_id and so forth. (users can anyway do NOT provide any src_id, and subscribe instead to ALL the existing (if any) src_id sources for that proto_id/evt_id combination) Each of the above tuple-specified event will be served on its own dedicated blocking notification chain. Upon a notification delivery all the users' registered notifier_t callbacks will be in turn invoked and fed with the event_id as @action param and a generated custom per-event struct _report as @data param. (as in include/linux/scmi_protocol.h) The final step of notification delivery via users' callback invocation is instead delegated to a pool of deferred workers (Kernel cmwq): each SCMI protocol has its own dedicated worker and dedicated queue to push events from the rx ISR to the worker. The series is marked as RFC mainly because: - the API as said is tentative and not EXPORTed; currently consisting of a generic interface like: scmi_register_event_notifier(proto_id, evt_id, *src_id, *nb) as found in scmi_protocol.h, or using the equivalent 'handle' operations in scmi_notify_ops if used by an scmi_driver. It's open for discussion. - no Event priorization has been considered: each protocol has its own queue and deferred worker instance, so as to avoid that one protocol flood can overrun a single queue and influence other protocols' notifications' delivery. But that's it, all the workers are unbound, low_pri cmwq workers. Should we enforce some sort of built-in prio amongst the events ? Should this priority instead be compile time configurable ? Again, open for discussion. - no configuration is possible: it can be imagined that on a real platform events' priority (if any) and events queues' depth could be something somehow compile-time configurable, but this is not addressed by this series at all. Based on scmi-next 5.6 [1], on top of: commit 5c8a47a5a91d ("firmware: arm_scmi: Make scmi core independent of the transport type") This series has been tested on JUNO with an experimental firmware only supporting Perf Notifications. Any thoughts ? Thanks Cristian ---- v1 --> v2: - dropped anti-tampering patch - rebased on top of scmi-for-next-5.6, which includes Viresh series that make SCMI core independent of transport (5c8a47a5a91d) - add a few new SCMI transport methods on top of Viresh patch to address needs of SCMI Notifications - reviewed/renamed scmi_handle_xfer_delayed_resp() - split main SCMI Notification core patch (~1k lines) into three chunks: protocol-registration / callbacks-registration / dispatch-and-delivery - removed awkward usage of IDR maps in favour of pure hashtables - added enable/disable refcounting in notification core (was broken in v1) - removed per-protocol candidate API: a single generic API is now proposed instead of scmi_register__event_notifier(evt_id, *src_id, *nb) - added handle->notify_ops as an alternative notification API for scmi_driver - moved ALL_SRCIDs enabled handling from protocol code to core code - reviewed protocol registration/unregistration logic to use devres - reviewed cleanup phase on shutdown - fixed ERROR: reference preceded by free as reported by kbuild test robot [1] git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux.git Cristian Marussi (10): firmware: arm_scmi: Add notifications support in transport layer firmware: arm_scmi: Add notification protocol-registration firmware: arm_scmi: Add notification callbacks-registration firmware: arm_scmi: Add notification dispatch and delivery firmware: arm_scmi: Enable notification core firmware: arm_scmi: Add Power notifications support firmware: arm_scmi: Add Perf notifications support firmware: arm_scmi: Add Sensor notifications support firmware: arm_scmi: Add Reset notifications support firmware: arm_scmi: Add Base notifications support Sudeep Holla (3): firmware: arm_scmi: Add receive buffer support for notifications firmware: arm_scmi: Update protocol commands and notification list firmware: arm_scmi: Add support for notifications message processing drivers/firmware/arm_scmi/Makefile | 2 +- drivers/firmware/arm_scmi/base.c | 121 +++ drivers/firmware/arm_scmi/bus.c | 11 + drivers/firmware/arm_scmi/common.h | 12 + drivers/firmware/arm_scmi/driver.c | 118 ++- drivers/firmware/arm_scmi/mailbox.c | 17 + drivers/firmware/arm_scmi/notify.c | 1102 +++++++++++++++++++++++++++ drivers/firmware/arm_scmi/notify.h | 78 ++ drivers/firmware/arm_scmi/perf.c | 140 +++- drivers/firmware/arm_scmi/power.c | 133 +++- drivers/firmware/arm_scmi/reset.c | 100 ++- drivers/firmware/arm_scmi/sensors.c | 77 +- drivers/firmware/arm_scmi/shmem.c | 15 + include/linux/scmi_protocol.h | 114 +++ 14 files changed, 2009 insertions(+), 31 deletions(-) create mode 100644 drivers/firmware/arm_scmi/notify.c create mode 100644 drivers/firmware/arm_scmi/notify.h -- 2.17.1