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
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
* (SCMI).
*
* Copyright (C) 2020-2022 OpenSynergy.
- * Copyright (C) 2021-2022 ARM Ltd.
+ * Copyright (C) 2021-2024 ARM Ltd.
*/
/**
#include <linux/completion.h>
#include <linux/errno.h>
+#include <linux/platform_device.h>
#include <linux/refcount.h>
#include <linux/slab.h>
#include <linux/virtio.h>
#include <uapi/linux/virtio_ids.h>
#include <uapi/linux/virtio_scmi.h>
-#include "common.h"
+#include "../common.h"
#define VIRTIO_MAX_RX_TIMEOUT_MS 60000
#define VIRTIO_SCMI_MAX_MSG_SIZE 128 /* Value may be increased. */
refcount_t users;
};
+static struct scmi_transport_core_operations *core;
+
/* Only one SCMI VirtIO device can possibly exist */
static struct virtio_device *scmi_vdev;
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);
}
* 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);
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;
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);
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,
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);
}
/**
* 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.
}
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,
.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;
}
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
.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 <igor.skalkin@opensynergy.com>");
+MODULE_AUTHOR("Peter Hilber <peter.hilber@opensynergy.com>");
+MODULE_AUTHOR("Cristian Marussi <cristian.marussi@arm.com>");
+MODULE_DESCRIPTION("SCMI VirtIO Transport driver");
+MODULE_LICENSE("GPL");
projects / thirdparty / kernel / linux.git / commitdiff
