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firmware: arm_scmi: Add atomic mode support to virtio transport
Add support for .mark_txdone and .poll_done transport operations to SCMI VirtIO transport as pre-requisites to enable atomic operations. Add a Kernel configuration option to enable SCMI VirtIO transport polling and atomic mode for selected SCMI transactions while leaving it default disabled. Link: https://lore.kernel.org/r/20220217131234.50328-4-cristian.marussi@arm.com Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Igor Skalkin <igor.skalkin@opensynergy.com> Cc: Peter Hilber <peter.hilber@opensynergy.com> Cc: virtualization@lists.linux-foundation.org Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
This commit is contained in:
parent
9a1699bda0
commit
5a3b7185c4
@ -118,6 +118,21 @@ config ARM_SCMI_TRANSPORT_VIRTIO_VERSION1_COMPLIANCE
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the ones implemented by kvmtool) and let the core Kernel VirtIO layer
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take care of the needed conversions, say N.
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config ARM_SCMI_TRANSPORT_VIRTIO_ATOMIC_ENABLE
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bool "Enable atomic mode for SCMI VirtIO transport"
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depends on ARM_SCMI_TRANSPORT_VIRTIO
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help
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Enable support of atomic operation for SCMI VirtIO based transport.
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If you want the SCMI VirtIO based transport to operate in atomic
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mode, avoiding any kind of sleeping behaviour for selected
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transactions on the TX path, answer Y.
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Enabling atomic mode operations allows any SCMI driver using this
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transport to optionally ask for atomic SCMI transactions and operate
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in atomic context too, at the price of using a number of busy-waiting
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primitives all over instead. If unsure say N.
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endif #ARM_SCMI_PROTOCOL
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config ARM_SCMI_POWER_DOMAIN
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@ -648,7 +648,8 @@ static void scmi_handle_notification(struct scmi_chan_info *cinfo,
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unpack_scmi_header(msg_hdr, &xfer->hdr);
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if (priv)
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xfer->priv = priv;
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/* Ensure order between xfer->priv store and following ops */
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smp_store_mb(xfer->priv, priv);
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info->desc->ops->fetch_notification(cinfo, info->desc->max_msg_size,
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xfer);
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scmi_notify(cinfo->handle, xfer->hdr.protocol_id,
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@ -680,7 +681,8 @@ static void scmi_handle_response(struct scmi_chan_info *cinfo,
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xfer->rx.len = info->desc->max_msg_size;
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if (priv)
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xfer->priv = priv;
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/* Ensure order between xfer->priv store and following ops */
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smp_store_mb(xfer->priv, priv);
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info->desc->ops->fetch_response(cinfo, xfer);
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trace_scmi_rx_done(xfer->transfer_id, xfer->hdr.id,
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@ -3,8 +3,8 @@
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* Virtio Transport driver for Arm System Control and Management Interface
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* (SCMI).
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*
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* Copyright (C) 2020-2021 OpenSynergy.
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* Copyright (C) 2021 ARM Ltd.
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* Copyright (C) 2020-2022 OpenSynergy.
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* Copyright (C) 2021-2022 ARM Ltd.
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*/
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/**
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@ -42,9 +42,14 @@
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* @cinfo: SCMI Tx or Rx channel
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* @free_lock: Protects access to the @free_list.
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* @free_list: List of unused scmi_vio_msg, maintained for Tx channels only
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* @deferred_tx_work: Worker for TX deferred replies processing
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* @deferred_tx_wq: Workqueue for TX deferred replies
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* @pending_lock: Protects access to the @pending_cmds_list.
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* @pending_cmds_list: List of pre-fetched commands queueud for later processing
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* @is_rx: Whether channel is an Rx channel
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* @max_msg: Maximum number of pending messages for this channel.
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* @lock: Protects access to all members except users, free_list.
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* @lock: Protects access to all members except users, free_list and
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* pending_cmds_list.
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* @shutdown_done: A reference to a completion used when freeing this channel.
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* @users: A reference count to currently active users of this channel.
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*/
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@ -54,14 +59,29 @@ struct scmi_vio_channel {
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/* lock to protect access to the free list. */
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spinlock_t free_lock;
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struct list_head free_list;
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/* lock to protect access to the pending list. */
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spinlock_t pending_lock;
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struct list_head pending_cmds_list;
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struct work_struct deferred_tx_work;
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struct workqueue_struct *deferred_tx_wq;
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bool is_rx;
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unsigned int max_msg;
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/* lock to protect access to all members except users, free_list */
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/*
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* Lock to protect access to all members except users, free_list and
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* pending_cmds_list
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*/
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spinlock_t lock;
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struct completion *shutdown_done;
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refcount_t users;
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};
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enum poll_states {
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VIO_MSG_NOT_POLLED,
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VIO_MSG_POLL_TIMEOUT,
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VIO_MSG_POLLING,
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VIO_MSG_POLL_DONE,
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};
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/**
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* struct scmi_vio_msg - Transport PDU information
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*
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@ -69,12 +89,23 @@ struct scmi_vio_channel {
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* @input: SDU used for (delayed) responses and notifications
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* @list: List which scmi_vio_msg may be part of
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* @rx_len: Input SDU size in bytes, once input has been received
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* @poll_idx: Last used index registered for polling purposes if this message
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* transaction reply was configured for polling.
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* @poll_status: Polling state for this message.
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* @poll_lock: A lock to protect @poll_status
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* @users: A reference count to track this message users and avoid premature
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* freeing (and reuse) when polling and IRQ execution paths interleave.
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*/
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struct scmi_vio_msg {
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struct scmi_msg_payld *request;
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struct scmi_msg_payld *input;
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struct list_head list;
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unsigned int rx_len;
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unsigned int poll_idx;
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enum poll_states poll_status;
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/* Lock to protect access to poll_status */
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spinlock_t poll_lock;
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refcount_t users;
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};
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/* Only one SCMI VirtIO device can possibly exist */
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@ -117,6 +148,7 @@ static void scmi_vio_channel_cleanup_sync(struct scmi_vio_channel *vioch)
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{
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unsigned long flags;
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DECLARE_COMPLETION_ONSTACK(vioch_shutdown_done);
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void *deferred_wq = NULL;
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/*
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* Prepare to wait for the last release if not already released
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@ -127,10 +159,19 @@ static void scmi_vio_channel_cleanup_sync(struct scmi_vio_channel *vioch)
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spin_unlock_irqrestore(&vioch->lock, flags);
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return;
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}
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vioch->shutdown_done = &vioch_shutdown_done;
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virtio_break_device(vioch->vqueue->vdev);
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if (!vioch->is_rx && vioch->deferred_tx_wq) {
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deferred_wq = vioch->deferred_tx_wq;
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/* Cannot be kicked anymore after this...*/
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vioch->deferred_tx_wq = NULL;
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}
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spin_unlock_irqrestore(&vioch->lock, flags);
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if (deferred_wq)
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destroy_workqueue(deferred_wq);
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scmi_vio_channel_release(vioch);
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/* Let any possibly concurrent RX path release the channel */
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@ -154,18 +195,34 @@ scmi_virtio_get_free_msg(struct scmi_vio_channel *vioch)
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list_del_init(&msg->list);
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spin_unlock_irqrestore(&vioch->free_lock, flags);
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/* Still no users, no need to acquire poll_lock */
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msg->poll_status = VIO_MSG_NOT_POLLED;
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refcount_set(&msg->users, 1);
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return msg;
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}
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/* Assumes to be called with vio channel acquired already */
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static void scmi_virtio_put_free_msg(struct scmi_vio_channel *vioch,
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struct scmi_vio_msg *msg)
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static inline bool scmi_vio_msg_acquire(struct scmi_vio_msg *msg)
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{
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unsigned long flags;
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return refcount_inc_not_zero(&msg->users);
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}
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spin_lock_irqsave(&vioch->free_lock, flags);
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list_add_tail(&msg->list, &vioch->free_list);
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spin_unlock_irqrestore(&vioch->free_lock, flags);
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/* Assumes to be called with vio channel acquired already */
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static inline bool scmi_vio_msg_release(struct scmi_vio_channel *vioch,
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struct scmi_vio_msg *msg)
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{
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bool ret;
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ret = refcount_dec_and_test(&msg->users);
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if (ret) {
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unsigned long flags;
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spin_lock_irqsave(&vioch->free_lock, flags);
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list_add_tail(&msg->list, &vioch->free_list);
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spin_unlock_irqrestore(&vioch->free_lock, flags);
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}
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return ret;
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}
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static bool scmi_vio_have_vq_rx(struct virtio_device *vdev)
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@ -206,7 +263,7 @@ static void scmi_finalize_message(struct scmi_vio_channel *vioch,
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if (vioch->is_rx)
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scmi_vio_feed_vq_rx(vioch, msg);
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else
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scmi_virtio_put_free_msg(vioch, msg);
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scmi_vio_msg_release(vioch, msg);
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}
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static void scmi_vio_complete_cb(struct virtqueue *vqueue)
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@ -230,6 +287,7 @@ static void scmi_vio_complete_cb(struct virtqueue *vqueue)
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virtqueue_disable_cb(vqueue);
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cb_enabled = false;
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}
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msg = virtqueue_get_buf(vqueue, &length);
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if (!msg) {
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if (virtqueue_enable_cb(vqueue)) {
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@ -260,6 +318,49 @@ static void scmi_vio_complete_cb(struct virtqueue *vqueue)
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}
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}
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static void scmi_vio_deferred_tx_worker(struct work_struct *work)
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{
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unsigned long flags;
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struct scmi_vio_channel *vioch;
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struct scmi_vio_msg *msg, *tmp;
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vioch = container_of(work, struct scmi_vio_channel, deferred_tx_work);
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if (!scmi_vio_channel_acquire(vioch))
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return;
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/*
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* Process pre-fetched messages: these could be non-polled messages or
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* late timed-out replies to polled messages dequeued by chance while
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* polling for some other messages: this worker is in charge to process
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* the valid non-expired messages and anyway finally free all of them.
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*/
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spin_lock_irqsave(&vioch->pending_lock, flags);
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/* Scan the list of possibly pre-fetched messages during polling. */
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list_for_each_entry_safe(msg, tmp, &vioch->pending_cmds_list, list) {
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list_del(&msg->list);
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/*
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* Channel is acquired here (cannot vanish) and this message
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* is no more processed elsewhere so no poll_lock needed.
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*/
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if (msg->poll_status == VIO_MSG_NOT_POLLED)
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scmi_rx_callback(vioch->cinfo,
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msg_read_header(msg->input), msg);
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/* Free the processed message once done */
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scmi_vio_msg_release(vioch, msg);
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}
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spin_unlock_irqrestore(&vioch->pending_lock, flags);
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/* Process possibly still pending messages */
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scmi_vio_complete_cb(vioch->vqueue);
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scmi_vio_channel_release(vioch);
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}
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static const char *const scmi_vio_vqueue_names[] = { "tx", "rx" };
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static vq_callback_t *scmi_vio_complete_callbacks[] = {
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@ -327,6 +428,19 @@ static int virtio_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
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vioch = &((struct scmi_vio_channel *)scmi_vdev->priv)[index];
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/* Setup a deferred worker for polling. */
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if (tx && !vioch->deferred_tx_wq) {
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vioch->deferred_tx_wq =
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alloc_workqueue(dev_name(&scmi_vdev->dev),
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WQ_UNBOUND | WQ_FREEZABLE | WQ_SYSFS,
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0);
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if (!vioch->deferred_tx_wq)
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return -ENOMEM;
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INIT_WORK(&vioch->deferred_tx_work,
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scmi_vio_deferred_tx_worker);
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}
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for (i = 0; i < vioch->max_msg; i++) {
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struct scmi_vio_msg *msg;
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@ -340,6 +454,8 @@ static int virtio_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
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GFP_KERNEL);
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if (!msg->request)
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return -ENOMEM;
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spin_lock_init(&msg->poll_lock);
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refcount_set(&msg->users, 1);
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}
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msg->input = devm_kzalloc(cinfo->dev, VIRTIO_SCMI_MAX_PDU_SIZE,
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@ -394,6 +510,21 @@ static int virtio_send_message(struct scmi_chan_info *cinfo,
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spin_lock_irqsave(&vioch->lock, flags);
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/*
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* If polling was requested for this transaction:
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* - retrieve last used index (will be used as polling reference)
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* - bind the polled message to the xfer via .priv
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* - grab an additional msg refcount for the poll-path
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*/
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if (xfer->hdr.poll_completion) {
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msg->poll_idx = virtqueue_enable_cb_prepare(vioch->vqueue);
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/* Still no users, no need to acquire poll_lock */
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msg->poll_status = VIO_MSG_POLLING;
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scmi_vio_msg_acquire(msg);
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/* Ensure initialized msg is visibly bound to xfer */
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smp_store_mb(xfer->priv, msg);
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}
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rc = virtqueue_add_sgs(vioch->vqueue, sgs, 1, 1, msg, GFP_ATOMIC);
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if (rc)
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dev_err(vioch->cinfo->dev,
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@ -403,8 +534,13 @@ static int virtio_send_message(struct scmi_chan_info *cinfo,
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spin_unlock_irqrestore(&vioch->lock, flags);
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if (rc)
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scmi_virtio_put_free_msg(vioch, msg);
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if (rc) {
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/* Ensure order between xfer->priv clear and vq feeding */
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smp_store_mb(xfer->priv, NULL);
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if (xfer->hdr.poll_completion)
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scmi_vio_msg_release(vioch, msg);
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scmi_vio_msg_release(vioch, msg);
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}
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scmi_vio_channel_release(vioch);
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@ -416,10 +552,8 @@ static void virtio_fetch_response(struct scmi_chan_info *cinfo,
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{
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struct scmi_vio_msg *msg = xfer->priv;
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if (msg) {
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if (msg)
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msg_fetch_response(msg->input, msg->rx_len, xfer);
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xfer->priv = NULL;
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}
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}
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static void virtio_fetch_notification(struct scmi_chan_info *cinfo,
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@ -427,10 +561,225 @@ static void virtio_fetch_notification(struct scmi_chan_info *cinfo,
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{
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struct scmi_vio_msg *msg = xfer->priv;
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if (msg) {
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if (msg)
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msg_fetch_notification(msg->input, msg->rx_len, max_len, xfer);
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xfer->priv = NULL;
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}
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/**
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* virtio_mark_txdone - Mark transmission done
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*
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* Free only completed polling transfer messages.
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*
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* Note that in the SCMI VirtIO transport we never explicitly release still
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* outstanding but timed-out messages by forcibly re-adding them to the
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* free-list inside the TX code path; we instead let IRQ/RX callbacks, or the
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* TX deferred worker, eventually clean up such messages once, finally, a late
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* reply is received and discarded (if ever).
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*
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* This approach was deemed preferable since those pending timed-out buffers are
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* still effectively owned by the SCMI platform VirtIO device even after timeout
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* expiration: forcibly freeing and reusing them before they had been returned
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* explicitly by the SCMI platform could lead to subtle bugs due to message
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* corruption.
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* An SCMI platform VirtIO device which never returns message buffers is
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* anyway broken and it will quickly lead to exhaustion of available messages.
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*
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* For this same reason, here, we take care to free only the polled messages
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* that had been somehow replied (only if not by chance already processed on the
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* IRQ path - the initial scmi_vio_msg_release() takes care of this) and also
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* any timed-out polled message if that indeed appears to have been at least
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* dequeued from the virtqueues (VIO_MSG_POLL_DONE): this is needed since such
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* messages won't be freed elsewhere. Any other polled message is marked as
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* VIO_MSG_POLL_TIMEOUT.
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*
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* Possible late replies to timed-out polled messages will be eventually freed
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* by RX callbacks if delivered on the IRQ path or by the deferred TX worker if
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* dequeued on some other polling path.
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*
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* @cinfo: SCMI channel info
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* @ret: Transmission return code
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* @xfer: Transfer descriptor
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*/
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static void virtio_mark_txdone(struct scmi_chan_info *cinfo, int ret,
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struct scmi_xfer *xfer)
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{
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unsigned long flags;
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struct scmi_vio_channel *vioch = cinfo->transport_info;
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struct scmi_vio_msg *msg = xfer->priv;
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if (!msg || !scmi_vio_channel_acquire(vioch))
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return;
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/* Ensure msg is unbound from xfer anyway at this point */
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smp_store_mb(xfer->priv, NULL);
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/* Must be a polled xfer and not already freed on the IRQ path */
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if (!xfer->hdr.poll_completion || scmi_vio_msg_release(vioch, msg)) {
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scmi_vio_channel_release(vioch);
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return;
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}
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spin_lock_irqsave(&msg->poll_lock, flags);
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/* Do not free timedout polled messages only if still inflight */
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if (ret != -ETIMEDOUT || msg->poll_status == VIO_MSG_POLL_DONE)
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scmi_vio_msg_release(vioch, msg);
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else if (msg->poll_status == VIO_MSG_POLLING)
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msg->poll_status = VIO_MSG_POLL_TIMEOUT;
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spin_unlock_irqrestore(&msg->poll_lock, flags);
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|
||||
scmi_vio_channel_release(vioch);
|
||||
}
|
||||
|
||||
/**
|
||||
* virtio_poll_done - Provide polling support for VirtIO transport
|
||||
*
|
||||
* @cinfo: SCMI channel info
|
||||
* @xfer: Reference to the transfer being poll for.
|
||||
*
|
||||
* VirtIO core provides a polling mechanism based only on last used indexes:
|
||||
* this means that it is possible to poll the virtqueues waiting for something
|
||||
* new to arrive from the host side, but the only way to check if the freshly
|
||||
* arrived buffer was indeed what we were waiting for is to compare the newly
|
||||
* arrived message descriptor with the one we are polling on.
|
||||
*
|
||||
* As a consequence it can happen to dequeue something different from the buffer
|
||||
* we were poll-waiting for: if that is the case such early fetched buffers are
|
||||
* then added to a the @pending_cmds_list list for later processing by a
|
||||
* dedicated deferred worker.
|
||||
*
|
||||
* So, basically, once something new is spotted we proceed to de-queue all the
|
||||
* freshly received used buffers until we found the one we were polling on, or,
|
||||
* we have 'seemingly' emptied the virtqueue; if some buffers are still pending
|
||||
* in the vqueue at the end of the polling loop (possible due to inherent races
|
||||
* in virtqueues handling mechanisms), we similarly kick the deferred worker
|
||||
* and let it process those, to avoid indefinitely looping in the .poll_done
|
||||
* busy-waiting helper.
|
||||
*
|
||||
* Finally, we delegate to the deferred worker also the final free of any timed
|
||||
* out reply to a polled message that we should dequeue.
|
||||
*
|
||||
* Note that, since we do NOT have per-message suppress notification mechanism,
|
||||
* 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
|
||||
* transparently terminated anyway.
|
||||
*
|
||||
* Return: True once polling has successfully completed.
|
||||
*/
|
||||
static bool virtio_poll_done(struct scmi_chan_info *cinfo,
|
||||
struct scmi_xfer *xfer)
|
||||
{
|
||||
bool pending, found = false;
|
||||
unsigned int length, any_prefetched = 0;
|
||||
unsigned long flags;
|
||||
struct scmi_vio_msg *next_msg, *msg = xfer->priv;
|
||||
struct scmi_vio_channel *vioch = cinfo->transport_info;
|
||||
|
||||
if (!msg)
|
||||
return true;
|
||||
|
||||
/*
|
||||
* Processed already by other polling loop on another CPU ?
|
||||
*
|
||||
* Note that this message is acquired on the poll path so cannot vanish
|
||||
* while inside this loop iteration even if concurrently processed on
|
||||
* the IRQ path.
|
||||
*
|
||||
* Avoid to acquire poll_lock since polled_status can be changed
|
||||
* in a relevant manner only later in this same thread of execution:
|
||||
* any other possible changes made concurrently by other polling loops
|
||||
* or by a reply delivered on the IRQ path have no meaningful impact on
|
||||
* this loop iteration: in other words it is harmless to allow this
|
||||
* possible race but let has avoid spinlocking with irqs off in this
|
||||
* initial part of the polling loop.
|
||||
*/
|
||||
if (msg->poll_status == VIO_MSG_POLL_DONE)
|
||||
return true;
|
||||
|
||||
if (!scmi_vio_channel_acquire(vioch))
|
||||
return true;
|
||||
|
||||
/* Has cmdq index moved at all ? */
|
||||
pending = virtqueue_poll(vioch->vqueue, msg->poll_idx);
|
||||
if (!pending) {
|
||||
scmi_vio_channel_release(vioch);
|
||||
return false;
|
||||
}
|
||||
|
||||
spin_lock_irqsave(&vioch->lock, flags);
|
||||
virtqueue_disable_cb(vioch->vqueue);
|
||||
|
||||
/*
|
||||
* Process all new messages till the polled-for message is found OR
|
||||
* the vqueue is empty.
|
||||
*/
|
||||
while ((next_msg = virtqueue_get_buf(vioch->vqueue, &length))) {
|
||||
bool next_msg_done = false;
|
||||
|
||||
/*
|
||||
* Mark any dequeued buffer message as VIO_MSG_POLL_DONE so
|
||||
* that can be properly freed even on timeout in mark_txdone.
|
||||
*/
|
||||
spin_lock(&next_msg->poll_lock);
|
||||
if (next_msg->poll_status == VIO_MSG_POLLING) {
|
||||
next_msg->poll_status = VIO_MSG_POLL_DONE;
|
||||
next_msg_done = true;
|
||||
}
|
||||
spin_unlock(&next_msg->poll_lock);
|
||||
|
||||
next_msg->rx_len = length;
|
||||
/* Is the message we were polling for ? */
|
||||
if (next_msg == msg) {
|
||||
found = true;
|
||||
break;
|
||||
} else if (next_msg_done) {
|
||||
/* Skip the rest if this was another polled msg */
|
||||
continue;
|
||||
}
|
||||
|
||||
/*
|
||||
* Enqueue for later processing any non-polled message and any
|
||||
* timed-out polled one that we happen to have dequeued.
|
||||
*/
|
||||
spin_lock(&next_msg->poll_lock);
|
||||
if (next_msg->poll_status == VIO_MSG_NOT_POLLED ||
|
||||
next_msg->poll_status == VIO_MSG_POLL_TIMEOUT) {
|
||||
spin_unlock(&next_msg->poll_lock);
|
||||
|
||||
any_prefetched++;
|
||||
spin_lock(&vioch->pending_lock);
|
||||
list_add_tail(&next_msg->list,
|
||||
&vioch->pending_cmds_list);
|
||||
spin_unlock(&vioch->pending_lock);
|
||||
} else {
|
||||
spin_unlock(&next_msg->poll_lock);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* When the polling loop has successfully terminated if something
|
||||
* else was queued in the meantime, it will be served by a deferred
|
||||
* worker OR by the normal IRQ/callback OR by other poll loops.
|
||||
*
|
||||
* If we are still looking for the polled reply, the polling index has
|
||||
* to be updated to the current vqueue last used index.
|
||||
*/
|
||||
if (found) {
|
||||
pending = !virtqueue_enable_cb(vioch->vqueue);
|
||||
} else {
|
||||
msg->poll_idx = virtqueue_enable_cb_prepare(vioch->vqueue);
|
||||
pending = virtqueue_poll(vioch->vqueue, msg->poll_idx);
|
||||
}
|
||||
|
||||
if (vioch->deferred_tx_wq && (any_prefetched || pending))
|
||||
queue_work(vioch->deferred_tx_wq, &vioch->deferred_tx_work);
|
||||
|
||||
spin_unlock_irqrestore(&vioch->lock, flags);
|
||||
|
||||
scmi_vio_channel_release(vioch);
|
||||
|
||||
return found;
|
||||
}
|
||||
|
||||
static const struct scmi_transport_ops scmi_virtio_ops = {
|
||||
@ -442,6 +791,8 @@ static const struct scmi_transport_ops scmi_virtio_ops = {
|
||||
.send_message = virtio_send_message,
|
||||
.fetch_response = virtio_fetch_response,
|
||||
.fetch_notification = virtio_fetch_notification,
|
||||
.mark_txdone = virtio_mark_txdone,
|
||||
.poll_done = virtio_poll_done,
|
||||
};
|
||||
|
||||
static int scmi_vio_probe(struct virtio_device *vdev)
|
||||
@ -484,6 +835,8 @@ static int scmi_vio_probe(struct virtio_device *vdev)
|
||||
spin_lock_init(&channels[i].lock);
|
||||
spin_lock_init(&channels[i].free_lock);
|
||||
INIT_LIST_HEAD(&channels[i].free_list);
|
||||
spin_lock_init(&channels[i].pending_lock);
|
||||
INIT_LIST_HEAD(&channels[i].pending_cmds_list);
|
||||
channels[i].vqueue = vqs[i];
|
||||
|
||||
sz = virtqueue_get_vring_size(channels[i].vqueue);
|
||||
@ -573,4 +926,5 @@ const struct scmi_desc scmi_virtio_desc = {
|
||||
.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),
|
||||
};
|
||||
|
Loading…
Reference in New Issue
Block a user