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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 8A1F0C433E9 for ; Tue, 12 Jan 2021 19:22:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5EDF02311F for ; Tue, 12 Jan 2021 19:22:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2406756AbhALTVp (ORCPT ); Tue, 12 Jan 2021 14:21:45 -0500 Received: from foss.arm.com ([217.140.110.172]:51748 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2406508AbhALTVo (ORCPT ); Tue, 12 Jan 2021 14:21:44 -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 C2D6A1042; Tue, 12 Jan 2021 11:20:58 -0800 (PST) Received: from e120937-lin.home (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B118E3F66E; Tue, 12 Jan 2021 11:20:56 -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, f.fainelli@gmail.com, etienne.carriere@linaro.org, thara.gopinath@linaro.org, vincent.guittot@linaro.org, souvik.chakravarty@arm.com, cristian.marussi@arm.com Subject: [PATCH v5 0/36] SCMI vendor protocols and modularization Date: Tue, 12 Jan 2021 19:19:42 +0000 Message-Id: <20210112192018.34994-1-cristian.marussi@arm.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi all, The current SCMI implementation does not provide an interface to easily develop and include a custom vendor protocol implementation as prescribed by the SCMI standard, also because, there is not currently any custom protocol in the upstream to justify the development of a custom interface and its maintenance. Moreover the current interface exposes protocol operations to the SCMI driver users attaching per-protocol operations directly to the handle structure, which, in this way, tends to grow indefinitely for each new protocol addition. Beside this, protocols private data are also exposed via handle *_priv pointers, making such private data accessible also to the SCMI drivers even if neither really needed nor advisable. This series wants to address this by simplifying the SCMI protocols interface and reducing it, roughly, to these common generic operations: - handle->devm_get_protocol() - handle->devm_put_protocol() - handle->notify_ops() All protocols' private data pointers are removed from handle too and made accessible only to the protocols code through dedicated internal helpers. The concept of protocol handle is also introduced in the SCMI protocol code to represent a protocol instance initialized against a specific SCMI instance (handle), so that all the new protocol code uses such protocol handles wherever previously SCMI handle was used: this enable tigther control of what is exposed to the protocol code vs the SCMI drivers. Moreover protocol initialization is moved away from device probe and now happens on demand when the first user shows up (first .get_protocol), while de-initialization is performed once the last user of the protocol, even in terms of registered notifications callback, is gone, with the SCMI core taking care to perform all the needed underlying resource accounting. This way any new future standard or custom protocol implementation will expose a common unified interface which does not need to be extended endlessly: no need to maintain a custom interface only for vendor protos. SCMI drivers written on top of standard or custom protocols will use this same common interface to access any protocol operations. All existent upstream SCMI drivers are converted to this new interface. In order to make this migration painless and to avoid the need of a big un-mergeable jumbo patch touching all over the protocols and drivers (like it was in v2), since v3 the migration process has been heavily split with a bit of transient code added along the way (to preserve bisectability) and finally removed towards the ends of the series. Protocols and SCMI drivers migration to the new interface happens along patches 10->29. Note that even in v5 all the related SCMI drivers maintainers are still NOT CC'ed given I am still sort of gather consensus about the interface itself. Leveraging this new centralized and common initialization flow we took care also to refactor and simplify protocol-events registration and remove *notify_priv from the handle interface making it accessible only to the notification core. Patch 35 builds on top of this new interface and introduces a mechanism to define an SCMI protocol as a full blown module (possibly loadable) while leaving the core dealing with proper resource accounting. Standard protocols are still kept as builtins in this series, though. Finally, patch 36 introduces dynamic SCMI devices creation to avoid having to update the static module device table in the core each time a new driver is added. The whole SCMI stack can still be built alternatively as a module, with all the standard protocols included in scmi-module.ko in such a case. On top of this series an example SCMI Custom protocol 0x99 and related SCMI Custom Dummy driver has been built and it is available at [1] as a series of DEBUG patches on top this same series. The series is currently based on for-next/scmi [2] on top of: commit 6054d97ab512 ("MAINTAINERS: Update ARM SCMI entry") Any feedback welcome. Thanks, Cristian --- v4 --> v5 - using standard kernel list instead of ad-hoc lists in 36/36 - renamed devm_get/put_ops to devm_get/put_protocol - dropped RFC patch on non devres get/put_ops v3 --> v4 - rebased on sudeep/for-next/scmi v5.11-rc1 - added a few comments more v2 --> v3 - added dynamic SCMI devices creation (getting rid of static device table) - heavy split of protocols and drivers migrations to the new interface - rebased on top of next-20201201 so migrating also: + SCMIv3.0 Voltage Domain protocol & SCMI Regulator + SCMIv3.0 Sensor Extensions v1 --> v2 - rebased on for-next/scmi v5.10-rc1 - introduced protocol handles - added devres managed devm_ variant for protocols operations - made all scmi_protocol refs const - introduced IDR to handle protocols instead of static array - refactored code around fast path [1]:https://gitlab.arm.com/linux-arm/linux-cm/-/commits/scmi_modules_ext_V5/ [2]:https://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux.git/log/?h=for-next/scmi Cristian Marussi (36): firmware: arm_scmi: review protocol registration interface firmware: arm_scmi: introduce protocol handle definitions firmware: arm_scmi: introduce devres get/put protocols operations firmware: arm_scmi: make notifications aware of protocols users firmware: arm_scmi: introduce new devres notification ops firmware: arm_scmi: refactor events registration firmware: arm_scmi: convert events registration to protocol handles firmware: arm_scmi: add new protocol handle core xfer ops firmware: arm_scmi: add helper to access revision area memory firmware: arm_scmi: port Base protocol to new interface firmware: arm_scmi: port Perf protocol to new protocols interface cpufreq: scmi: port driver to the new scmi_perf_proto_ops interface firmware: arm_scmi: remove legacy scmi_perf_ops protocol interface firmware: arm_scmi: port Power protocol to new protocols interface firmware: arm_scmi: port GenPD driver to the new scmi_power_proto_ops interface firmware: arm_scmi: remove legacy scmi_power_ops protocol interface firmware: arm_scmi: port Clock protocol to new protocols interface clk: scmi: port driver to the new scmi_clk_proto_ops interface firmware: arm_scmi: remove legacy scmi_clk_ops protocol interface firmware: arm_scmi: port Reset protocol to new protocols interface reset: reset-scmi: port driver to the new scmi_reset_proto_ops interface firmware: arm_scmi: remove legacy scmi_reset_ops protocol interface firmware: arm_scmi: port Sensor protocol to new protocols interface hwmon: (scmi) port driver to the new scmi_sensor_proto_ops interface firmware: arm_scmi: remove legacy scmi_sensor_ops protocol interface firmware: arm_scmi: port SystemPower protocol to new protocols interface firmware: arm_scmi: port Voltage protocol to new protocols interface regulator: scmi: port driver to the new scmi_voltage_proto_ops interface firmware: arm_scmi: remove legacy scmi_voltage_ops protocol interface firmware: arm_scmi: make references to handle const firmware: arm_scmi: cleanup legacy protocol init code firmware: arm_scmi: cleanup unused core xfer wrappers firmware: arm_scmi: cleanup events registration transient code firmware: arm_scmi: make notify_priv really private firmware: arm_scmi: add protocol modularization support firmware: arm_scmi: add dynamic scmi devices creation drivers/clk/clk-scmi.c | 27 +- drivers/cpufreq/scmi-cpufreq.c | 37 +- drivers/firmware/arm_scmi/base.c | 140 ++-- drivers/firmware/arm_scmi/bus.c | 100 ++- drivers/firmware/arm_scmi/clock.c | 129 ++-- drivers/firmware/arm_scmi/common.h | 117 +++- drivers/firmware/arm_scmi/driver.c | 759 +++++++++++++++++++-- drivers/firmware/arm_scmi/notify.c | 297 ++++++-- drivers/firmware/arm_scmi/notify.h | 38 +- drivers/firmware/arm_scmi/perf.c | 262 +++---- drivers/firmware/arm_scmi/power.c | 134 ++-- drivers/firmware/arm_scmi/reset.c | 146 ++-- drivers/firmware/arm_scmi/scmi_pm_domain.c | 26 +- drivers/firmware/arm_scmi/sensors.c | 230 ++++--- drivers/firmware/arm_scmi/system.c | 61 +- drivers/firmware/arm_scmi/voltage.c | 122 ++-- drivers/hwmon/scmi-hwmon.c | 24 +- drivers/regulator/scmi-regulator.c | 40 +- drivers/reset/reset-scmi.c | 33 +- include/linux/scmi_protocol.h | 183 ++--- 20 files changed, 1996 insertions(+), 909 deletions(-) -- 2.17.1