From patchwork Mon Aug 12 17:33:39 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Cristian Marussi X-Patchwork-Id: 13760890 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 7DB19C52D7C for ; Mon, 12 Aug 2024 17:39:41 +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=VeTdLzQvuh2523U/4BWJziTircusZ+2XAEYHDoES4zY=; b=jNly1Tmt8DZbIW7DtGl3ZR+/eW tIr4ffdtRaB3owmHAo1w6OM5bIPwNqj/7BEpq1VPGyI4UE01pILS6oycWtza5LvtnCEDdkgNPbO6D W+vX1ftxF7pYx/ruPpxRYBDfMf5sG6qWpu3WRddVrgM0mMNKcAqMR5gjpmBzKMUvQ2IgsYYTZuTSQ wicT4oWFx9G36Fo43kYtsijY0pB5LpDxEG1SK24BTlQ3wnLVTAdF0aU6dy/xwB+vzbGumfdCLg6oY pbvNI+A7ZRDsVU3s/EcZN2sN+wfjVCcVFUjTJ0e0EYfdmLL7llPXNsD4M94BxfXRw0kUHhSro4Qi7 MEB7ZEOw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sdZ12-000000013ot-0FAz; Mon, 12 Aug 2024 17:39:32 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sdYwF-000000012XG-3g2o for linux-arm-kernel@lists.infradead.org; Mon, 12 Aug 2024 17:34:37 +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 1AB53FEC; Mon, 12 Aug 2024 10:35:01 -0700 (PDT) Received: from pluto.guestnet.cambridge.arm.com (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 30CC03F40C; Mon, 12 Aug 2024 10:34:32 -0700 (PDT) From: Cristian Marussi To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, arm-scmi@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, quic_nkela@quicinc.com, ptosi@google.com, dan.carpenter@linaro.org, souvik.chakravarty@arm.com, Cristian Marussi , "Michael S . Tsirkin" , Igor Skalkin , Peter Hilber Subject: [PATCH v4 8/9] firmware: arm_scmi: Make VirtIO transport a standalone driver Date: Mon, 12 Aug 2024 18:33:39 +0100 Message-ID: <20240812173340.3912830-9-cristian.marussi@arm.com> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240812173340.3912830-1-cristian.marussi@arm.com> References: <20240812173340.3912830-1-cristian.marussi@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240812_103436_047324_80811221 X-CRM114-Status: GOOD ( 26.18 ) 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 Make SCMI VirtIO transport a standalone driver that can be optionally loaded as a module. CC: Michael S. Tsirkin CC: Igor Skalkin CC: Peter Hilber Signed-off-by: Cristian Marussi --- v3 --> v4 - dropped MODULE_ALIAS - moved VIRTIO transport to its own subdir and submenu v2 --> v3 - fixed spacing in Kconfig and Copyright - use new params in DEFINE_SCMI_TRANSPORT_DRIVER v1 --> v2 - handle platform_driver_register() failures - make scmi_virtio_desc static | Reported-by: kernel test robot | Closes: https://lore.kernel.org/oe-kbuild-all/202407081344.9OceqFie-lkp@intel.com/ --- drivers/firmware/arm_scmi/Kconfig | 41 ------- drivers/firmware/arm_scmi/Makefile | 1 - drivers/firmware/arm_scmi/common.h | 3 - drivers/firmware/arm_scmi/driver.c | 3 - drivers/firmware/arm_scmi/transports/Kconfig | 43 ++++++++ drivers/firmware/arm_scmi/transports/Makefile | 2 + .../arm_scmi/{ => transports}/virtio.c | 103 +++++++++--------- 7 files changed, 99 insertions(+), 97 deletions(-) rename drivers/firmware/arm_scmi/{ => transports}/virtio.c (94%) diff --git a/drivers/firmware/arm_scmi/Kconfig b/drivers/firmware/arm_scmi/Kconfig index b5e3634a8399..67053c1862d1 100644 --- a/drivers/firmware/arm_scmi/Kconfig +++ b/drivers/firmware/arm_scmi/Kconfig @@ -71,47 +71,6 @@ config ARM_SCMI_DEBUG_COUNTERS source "drivers/firmware/arm_scmi/transports/Kconfig" -config ARM_SCMI_TRANSPORT_VIRTIO - bool "SCMI transport based on VirtIO" - depends on VIRTIO=y || VIRTIO=ARM_SCMI_PROTOCOL - select ARM_SCMI_HAVE_TRANSPORT - select ARM_SCMI_HAVE_MSG - help - This enables the virtio based transport for SCMI. - - If you want the ARM SCMI PROTOCOL stack to include support for a - transport based on VirtIO, answer Y. - -config ARM_SCMI_TRANSPORT_VIRTIO_VERSION1_COMPLIANCE - bool "SCMI VirtIO transport Version 1 compliance" - depends on ARM_SCMI_TRANSPORT_VIRTIO - default y - help - This enforces strict compliance with VirtIO Version 1 specification. - - If you want the ARM SCMI VirtIO transport layer to refuse to work - with Legacy VirtIO backends and instead support only VirtIO Version 1 - devices (or above), answer Y. - - If you want instead to support also old Legacy VirtIO backends (like - the ones implemented by kvmtool) and let the core Kernel VirtIO layer - take care of the needed conversions, say N. - -config ARM_SCMI_TRANSPORT_VIRTIO_ATOMIC_ENABLE - bool "Enable atomic mode for SCMI VirtIO transport" - depends on ARM_SCMI_TRANSPORT_VIRTIO - help - Enable support of atomic operation for SCMI VirtIO based transport. - - If you want the SCMI VirtIO based transport to operate in atomic - mode, avoiding any kind of sleeping behaviour for selected - transactions on the TX path, answer Y. - - Enabling atomic mode operations allows any SCMI driver using this - transport to optionally ask for atomic SCMI transactions and operate - in atomic context too, at the price of using a number of busy-waiting - primitives all over instead. If unsure say N. - endif #ARM_SCMI_PROTOCOL config ARM_SCMI_POWER_CONTROL diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile index b80b302186da..dc786f8215b6 100644 --- a/drivers/firmware/arm_scmi/Makefile +++ b/drivers/firmware/arm_scmi/Makefile @@ -6,7 +6,6 @@ scmi-driver-y = driver.o notify.o scmi-driver-$(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT) += raw_mode.o scmi-transport-$(CONFIG_ARM_SCMI_HAVE_SHMEM) = shmem.o scmi-transport-$(CONFIG_ARM_SCMI_HAVE_MSG) += msg.o -scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO) += virtio.o scmi-protocols-y := base.o clock.o perf.o power.o reset.o sensors.o system.o voltage.o powercap.o scmi-protocols-y += pinctrl.o scmi-module-objs := $(scmi-driver-y) $(scmi-protocols-y) $(scmi-transport-y) diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h index 18026d446b59..7a53412fc41c 100644 --- a/drivers/firmware/arm_scmi/common.h +++ b/drivers/firmware/arm_scmi/common.h @@ -286,9 +286,6 @@ int scmi_xfer_raw_inflight_register(const struct scmi_handle *handle, int scmi_xfer_raw_wait_for_message_response(struct scmi_chan_info *cinfo, struct scmi_xfer *xfer, unsigned int timeout_ms); -#ifdef CONFIG_ARM_SCMI_TRANSPORT_VIRTIO -extern const struct scmi_desc scmi_virtio_desc; -#endif void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr, void *priv); diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index 084936e9575d..12643b4c0db3 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -3318,9 +3318,6 @@ ATTRIBUTE_GROUPS(versions); /* Each compatible listed below must have descriptor associated with it */ static const struct of_device_id scmi_of_match[] = { -#ifdef CONFIG_ARM_SCMI_TRANSPORT_VIRTIO - { .compatible = "arm,scmi-virtio", .data = &scmi_virtio_desc}, -#endif { /* Sentinel */ }, }; diff --git a/drivers/firmware/arm_scmi/transports/Kconfig b/drivers/firmware/arm_scmi/transports/Kconfig index 7d478a4f69df..57eccf316e26 100644 --- a/drivers/firmware/arm_scmi/transports/Kconfig +++ b/drivers/firmware/arm_scmi/transports/Kconfig @@ -77,4 +77,47 @@ config ARM_SCMI_TRANSPORT_OPTEE This driver can also be built as a module. If so, the module will be called scmi_transport_optee. +config ARM_SCMI_TRANSPORT_VIRTIO + tristate "SCMI transport based on VirtIO" + depends on VIRTIO + select ARM_SCMI_HAVE_TRANSPORT + select ARM_SCMI_HAVE_MSG + help + This enables the virtio based transport for SCMI. + + If you want the ARM SCMI PROTOCOL stack to include support for a + transport based on VirtIO, answer Y. + This driver can also be built as a module. If so, the module + will be called scmi_transport_virtio. + +config ARM_SCMI_TRANSPORT_VIRTIO_VERSION1_COMPLIANCE + bool "SCMI VirtIO transport Version 1 compliance" + depends on ARM_SCMI_TRANSPORT_VIRTIO + default y + help + This enforces strict compliance with VirtIO Version 1 specification. + + If you want the ARM SCMI VirtIO transport layer to refuse to work + with Legacy VirtIO backends and instead support only VirtIO Version 1 + devices (or above), answer Y. + + If you want instead to support also old Legacy VirtIO backends (like + the ones implemented by kvmtool) and let the core Kernel VirtIO layer + take care of the needed conversions, say N. + +config ARM_SCMI_TRANSPORT_VIRTIO_ATOMIC_ENABLE + bool "Enable atomic mode for SCMI VirtIO transport" + depends on ARM_SCMI_TRANSPORT_VIRTIO + help + Enable support of atomic operation for SCMI VirtIO based transport. + + If you want the SCMI VirtIO based transport to operate in atomic + mode, avoiding any kind of sleeping behaviour for selected + transactions on the TX path, answer Y. + + Enabling atomic mode operations allows any SCMI driver using this + transport to optionally ask for atomic SCMI transactions and operate + in atomic context too, at the price of using a number of busy-waiting + primitives all over instead. If unsure say N. + endmenu diff --git a/drivers/firmware/arm_scmi/transports/Makefile b/drivers/firmware/arm_scmi/transports/Makefile index 7c06d36a38fb..b08686571712 100644 --- a/drivers/firmware/arm_scmi/transports/Makefile +++ b/drivers/firmware/arm_scmi/transports/Makefile @@ -5,3 +5,5 @@ scmi_transport_smc-objs := smc.o obj-$(CONFIG_ARM_SCMI_TRANSPORT_SMC) += scmi_transport_smc.o scmi_transport_optee-objs := optee.o obj-$(CONFIG_ARM_SCMI_TRANSPORT_OPTEE) += scmi_transport_optee.o +scmi_transport_virtio-objs := virtio.o +obj-$(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO) += scmi_transport_virtio.o diff --git a/drivers/firmware/arm_scmi/virtio.c b/drivers/firmware/arm_scmi/transports/virtio.c similarity index 94% rename from drivers/firmware/arm_scmi/virtio.c rename to drivers/firmware/arm_scmi/transports/virtio.c index e8d38e822c7e..c107579e7fe7 100644 --- a/drivers/firmware/arm_scmi/virtio.c +++ b/drivers/firmware/arm_scmi/transports/virtio.c @@ -4,7 +4,7 @@ * (SCMI). * * Copyright (C) 2020-2022 OpenSynergy. - * Copyright (C) 2021-2022 ARM Ltd. + * Copyright (C) 2021-2024 ARM Ltd. */ /** @@ -19,6 +19,7 @@ #include #include +#include #include #include #include @@ -27,7 +28,7 @@ #include #include -#include "common.h" +#include "../common.h" #define VIRTIO_MAX_RX_TIMEOUT_MS 60000 #define VIRTIO_SCMI_MAX_MSG_SIZE 128 /* Value may be increased. */ @@ -108,6 +109,8 @@ struct scmi_vio_msg { refcount_t users; }; +static struct scmi_transport_core_operations *core; + /* Only one SCMI VirtIO device can possibly exist */ static struct virtio_device *scmi_vdev; @@ -294,8 +297,9 @@ static void scmi_vio_complete_cb(struct virtqueue *vqueue) if (msg) { msg->rx_len = length; - scmi_rx_callback(vioch->cinfo, - scmi_msg_ops.read_header(msg->input), msg); + core->rx_callback(vioch->cinfo, + core->msg->read_header(msg->input), + msg); scmi_finalize_message(vioch, msg); } @@ -339,8 +343,9 @@ static void scmi_vio_deferred_tx_worker(struct work_struct *work) * is no more processed elsewhere so no poll_lock needed. */ if (msg->poll_status == VIO_MSG_NOT_POLLED) - scmi_rx_callback(vioch->cinfo, - scmi_msg_ops.read_header(msg->input), msg); + core->rx_callback(vioch->cinfo, + core->msg->read_header(msg->input), + msg); /* Free the processed message once done */ scmi_vio_msg_release(vioch, msg); @@ -366,23 +371,6 @@ static unsigned int virtio_get_max_msg(struct scmi_chan_info *base_cinfo) return vioch->max_msg; } -static int virtio_link_supplier(struct device *dev) -{ - if (!scmi_vdev) { - dev_notice(dev, - "Deferring probe after not finding a bound scmi-virtio device\n"); - return -EPROBE_DEFER; - } - - if (!device_link_add(dev, &scmi_vdev->dev, - DL_FLAG_AUTOREMOVE_CONSUMER)) { - dev_err(dev, "Adding link to supplier virtio device failed\n"); - return -ECANCELED; - } - - return 0; -} - static bool virtio_chan_available(struct device_node *of_node, int idx) { struct scmi_vio_channel *channels, *vioch = NULL; @@ -510,10 +498,10 @@ static int virtio_send_message(struct scmi_chan_info *cinfo, return -EBUSY; } - scmi_msg_ops.tx_prepare(msg->request, xfer); + core->msg->tx_prepare(msg->request, xfer); - sg_init_one(&sg_out, msg->request, scmi_msg_ops.command_size(xfer)); - sg_init_one(&sg_in, msg->input, scmi_msg_ops.response_size(xfer)); + sg_init_one(&sg_out, msg->request, core->msg->command_size(xfer)); + sg_init_one(&sg_in, msg->input, core->msg->response_size(xfer)); spin_lock_irqsave(&vioch->lock, flags); @@ -560,7 +548,7 @@ static void virtio_fetch_response(struct scmi_chan_info *cinfo, struct scmi_vio_msg *msg = xfer->priv; if (msg) - scmi_msg_ops.fetch_response(msg->input, msg->rx_len, xfer); + core->msg->fetch_response(msg->input, msg->rx_len, xfer); } static void virtio_fetch_notification(struct scmi_chan_info *cinfo, @@ -569,7 +557,8 @@ static void virtio_fetch_notification(struct scmi_chan_info *cinfo, struct scmi_vio_msg *msg = xfer->priv; if (msg) - scmi_msg_ops.fetch_notification(msg->input, msg->rx_len, max_len, xfer); + core->msg->fetch_notification(msg->input, msg->rx_len, + max_len, xfer); } /** @@ -669,7 +658,7 @@ static void virtio_mark_txdone(struct scmi_chan_info *cinfo, int ret, * the message we are polling for could be alternatively delivered via usual * IRQs callbacks on another core which happened to have IRQs enabled while we * are actively polling for it here: in such a case it will be handled as such - * by scmi_rx_callback() and the polling loop in the SCMI Core TX path will be + * by rx_callback() and the polling loop in the SCMI Core TX path will be * transparently terminated anyway. * * Return: True once polling has successfully completed. @@ -790,7 +779,6 @@ static bool virtio_poll_done(struct scmi_chan_info *cinfo, } static const struct scmi_transport_ops scmi_virtio_ops = { - .link_supplier = virtio_link_supplier, .chan_available = virtio_chan_available, .chan_setup = virtio_chan_setup, .chan_free = virtio_chan_free, @@ -802,6 +790,23 @@ static const struct scmi_transport_ops scmi_virtio_ops = { .poll_done = virtio_poll_done, }; +static const struct scmi_desc scmi_virtio_desc = { + .ops = &scmi_virtio_ops, + /* for non-realtime virtio devices */ + .max_rx_timeout_ms = VIRTIO_MAX_RX_TIMEOUT_MS, + .max_msg = 0, /* overridden by virtio_get_max_msg() */ + .max_msg_size = VIRTIO_SCMI_MAX_MSG_SIZE, + .atomic_enabled = IS_ENABLED(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO_ATOMIC_ENABLE), +}; + +static const struct of_device_id scmi_of_match[] = { + { .compatible = "arm,scmi-virtio" }, + { /* Sentinel */ }, +}; + +DEFINE_SCMI_TRANSPORT_DRIVER(scmi_virtio, scmi_virtio_driver, scmi_virtio_desc, + scmi_of_match, core); + static int scmi_vio_probe(struct virtio_device *vdev) { struct device *dev = &vdev->dev; @@ -861,14 +866,27 @@ static int scmi_vio_probe(struct virtio_device *vdev) } vdev->priv = channels; + /* Ensure initialized scmi_vdev is visible */ smp_store_mb(scmi_vdev, vdev); + ret = platform_driver_register(&scmi_virtio_driver); + if (ret) { + vdev->priv = NULL; + vdev->config->del_vqs(vdev); + /* Ensure NULLified scmi_vdev is visible */ + smp_store_mb(scmi_vdev, NULL); + + return ret; + } + return 0; } static void scmi_vio_remove(struct virtio_device *vdev) { + platform_driver_unregister(&scmi_virtio_driver); + /* * Once we get here, virtio_chan_free() will have already been called by * the SCMI core for any existing channel and, as a consequence, all the @@ -913,23 +931,10 @@ static struct virtio_driver virtio_scmi_driver = { .validate = scmi_vio_validate, }; -static int __init virtio_scmi_init(void) -{ - return register_virtio_driver(&virtio_scmi_driver); -} - -static void virtio_scmi_exit(void) -{ - unregister_virtio_driver(&virtio_scmi_driver); -} +module_virtio_driver(virtio_scmi_driver); -const struct scmi_desc scmi_virtio_desc = { - .transport_init = virtio_scmi_init, - .transport_exit = virtio_scmi_exit, - .ops = &scmi_virtio_ops, - /* for non-realtime virtio devices */ - .max_rx_timeout_ms = VIRTIO_MAX_RX_TIMEOUT_MS, - .max_msg = 0, /* overridden by virtio_get_max_msg() */ - .max_msg_size = VIRTIO_SCMI_MAX_MSG_SIZE, - .atomic_enabled = IS_ENABLED(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO_ATOMIC_ENABLE), -}; +MODULE_AUTHOR("Igor Skalkin "); +MODULE_AUTHOR("Peter Hilber "); +MODULE_AUTHOR("Cristian Marussi "); +MODULE_DESCRIPTION("SCMI VirtIO Transport driver"); +MODULE_LICENSE("GPL");