diff options
Diffstat (limited to 'meta-egvirt/recipes-kernel/linux/linux-yocto/virtio-scmi/0010-firmware-arm_scmi-Add-virtio-transport.patch')
-rw-r--r-- | meta-egvirt/recipes-kernel/linux/linux-yocto/virtio-scmi/0010-firmware-arm_scmi-Add-virtio-transport.patch | 756 |
1 files changed, 0 insertions, 756 deletions
diff --git a/meta-egvirt/recipes-kernel/linux/linux-yocto/virtio-scmi/0010-firmware-arm_scmi-Add-virtio-transport.patch b/meta-egvirt/recipes-kernel/linux/linux-yocto/virtio-scmi/0010-firmware-arm_scmi-Add-virtio-transport.patch deleted file mode 100644 index 35ea04f8..00000000 --- a/meta-egvirt/recipes-kernel/linux/linux-yocto/virtio-scmi/0010-firmware-arm_scmi-Add-virtio-transport.patch +++ /dev/null @@ -1,756 +0,0 @@ -From 7b9f3fe0766d6d36ca7465e54754df51ca175079 Mon Sep 17 00:00:00 2001 -From: Igor Skalkin <igor.skalkin@opensynergy.com> -Date: Thu, 5 Nov 2020 22:21:16 +0100 -Subject: [PATCH] firmware: arm_scmi: Add virtio transport - -This transport enables accessing an SCMI platform as a virtio device. - -Implement an SCMI virtio driver according to the virtio SCMI device spec -patch v5 [1]. Virtio device id 32 has been reserved for the SCMI device -[2]. - -The virtio transport has one tx channel (virtio cmdq, A2P channel) and -at most one rx channel (virtio eventq, P2A channel). - -The following feature bit defined in [1] is not implemented: -VIRTIO_SCMI_F_SHARED_MEMORY. - -After the preparatory patches, implement the virtio transport as -paraphrased: - -Only support a single arm-scmi device (which is consistent with the SCMI -spec). Call scmi-virtio init from arm-scmi module init. During the -arm-scmi probing, link to the first probed scmi-virtio device. Defer -arm-scmi probing if no scmi-virtio device is bound yet. - -Use the scmi_xfer tx/rx buffers for data exchange with the virtio device -in order to avoid redundant maintenance of additional buffers. Allocate -the buffers in the SCMI transport, and prepend room for a small header -used by the virtio transport to the tx/rx buffers. - -For simplicity, restrict the number of messages which can be pending -simultaneously according to the virtqueue capacity. (The virtqueue sizes -are negotiated with the virtio device.) - -As soon as rx channel message buffers are allocated or have been read -out by the arm-scmi driver, feed them to the virtio device. - -Since some virtio devices may not have the short response time exhibited -by SCMI platforms using other transports, set a generous response -timeout. - -Limitations: - -Do not adjust the other SCMI timeouts for delayed response and polling -for now, since these timeouts are only relevant in special cases which -are not yet deemed relevant for this transport. - -To do (as discussed in the cover letter): - -- Avoid re-use of buffers still being used by the virtio device on - timeouts. - -- Avoid race conditions on receiving messages during/after channel free - on driver probe failure or remove. - -[1] https://lists.oasis-open.org/archives/virtio-comment/202005/msg00096.html -[2] https://www.oasis-open.org/committees/ballot.php?id=3496 - -Co-developed-by: Peter Hilber <peter.hilber@opensynergy.com> -Signed-off-by: Peter Hilber <peter.hilber@opensynergy.com> -Signed-off-by: Igor Skalkin <igor.skalkin@opensynergy.com> -Signed-off-by: Vasyl Vavrychuk <vasyl.vavrychuk@opensynergy.com> ---- - MAINTAINERS | 1 + - drivers/firmware/Kconfig | 12 +- - drivers/firmware/arm_scmi/Makefile | 1 + - drivers/firmware/arm_scmi/common.h | 14 + - drivers/firmware/arm_scmi/driver.c | 11 + - drivers/firmware/arm_scmi/virtio.c | 493 +++++++++++++++++++++++++++++ - include/uapi/linux/virtio_ids.h | 1 + - include/uapi/linux/virtio_scmi.h | 41 +++ - 8 files changed, 573 insertions(+), 1 deletion(-) - create mode 100644 drivers/firmware/arm_scmi/virtio.c - create mode 100644 include/uapi/linux/virtio_scmi.h - -diff --git a/MAINTAINERS b/MAINTAINERS -index 49772b741967..d223a5c3f465 100644 ---- a/MAINTAINERS -+++ b/MAINTAINERS -@@ -16973,6 +16973,7 @@ F: drivers/firmware/arm_scpi.c - F: drivers/reset/reset-scmi.c - F: include/linux/sc[mp]i_protocol.h - F: include/trace/events/scmi.h -+F: include/uapi/linux/virtio_scmi.h - - SYSTEM RESET/SHUTDOWN DRIVERS - M: Sebastian Reichel <sre@kernel.org> -diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig -index 30a85d38d0c0..82e97904bcae 100644 ---- a/drivers/firmware/Kconfig -+++ b/drivers/firmware/Kconfig -@@ -9,7 +9,7 @@ menu "Firmware Drivers" - config ARM_SCMI_PROTOCOL - tristate "ARM System Control and Management Interface (SCMI) Message Protocol" - depends on ARM || ARM64 || COMPILE_TEST -- depends on ARM_SCMI_HAVE_SHMEM -+ depends on ARM_SCMI_HAVE_SHMEM || VIRTIO_SCMI - help - ARM System Control and Management Interface (SCMI) protocol is a - set of operating system-independent software interfaces that are -@@ -34,6 +34,16 @@ config ARM_SCMI_HAVE_SHMEM - This declares whether a shared memory based transport for SCMI is - available. - -+config VIRTIO_SCMI -+ bool "Virtio transport for SCMI" -+ default n -+ depends on VIRTIO -+ help -+ This enables the virtio based transport for SCMI. -+ -+ If you want to use the ARM SCMI protocol between the virtio guest and -+ a host providing a virtio SCMI device, answer Y. -+ - config ARM_SCMI_POWER_DOMAIN - tristate "SCMI power domain driver" - depends on ARM_SCMI_PROTOCOL || (COMPILE_TEST && OF) -diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile -index 3cc7fa40a464..25caea5e1969 100644 ---- a/drivers/firmware/arm_scmi/Makefile -+++ b/drivers/firmware/arm_scmi/Makefile -@@ -4,6 +4,7 @@ scmi-driver-y = driver.o notify.o - scmi-transport-$(CONFIG_ARM_SCMI_HAVE_SHMEM) = shmem.o - scmi-transport-$(CONFIG_MAILBOX) += mailbox.o - scmi-transport-$(CONFIG_HAVE_ARM_SMCCC_DISCOVERY) += smc.o -+scmi-transport-$(CONFIG_VIRTIO_SCMI) += virtio.o - scmi-protocols-y = base.o clock.o perf.o power.o reset.o sensors.o system.o - scmi-module-objs := $(scmi-bus-y) $(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 13c9ac176b23..b46dfe84e78b 100644 ---- a/drivers/firmware/arm_scmi/common.h -+++ b/drivers/firmware/arm_scmi/common.h -@@ -165,6 +165,17 @@ int scmi_base_protocol_init(struct scmi_handle *h); - int __init scmi_bus_init(void); - void __exit scmi_bus_exit(void); - -+#ifdef CONFIG_VIRTIO_SCMI -+int __init virtio_scmi_init(void); -+void __exit virtio_scmi_exit(void); -+#else -+static inline int __init virtio_scmi_init(void) -+{ -+ return 0; -+} -+#define virtio_scmi_exit() do { } while (0) -+#endif -+ - #define DECLARE_SCMI_REGISTER_UNREGISTER(func) \ - int __init scmi_##func##_register(void); \ - void __exit scmi_##func##_unregister(void) -@@ -263,6 +274,9 @@ extern const struct scmi_desc scmi_mailbox_desc; - #ifdef CONFIG_HAVE_ARM_SMCCC - extern const struct scmi_desc scmi_smc_desc; - #endif -+#ifdef CONFIG_VIRTIO_SCMI -+extern const struct scmi_desc scmi_virtio_desc; -+#endif - - int scmi_set_transport_info(struct device *dev, void *transport_info); - void *scmi_get_transport_info(struct device *dev); -diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c -index 93ce17bb4079..540a55285349 100644 ---- a/drivers/firmware/arm_scmi/driver.c -+++ b/drivers/firmware/arm_scmi/driver.c -@@ -996,6 +996,9 @@ static const struct of_device_id scmi_of_match[] = { - #endif - #ifdef CONFIG_HAVE_ARM_SMCCC_DISCOVERY - { .compatible = "arm,scmi-smc", .data = &scmi_smc_desc}, -+#endif -+#ifdef CONFIG_VIRTIO_SCMI -+ { .compatible = "arm,scmi-virtio", .data = &scmi_virtio_desc}, - #endif - { /* Sentinel */ }, - }; -@@ -1014,8 +1017,14 @@ static struct platform_driver scmi_driver = { - - static int __init scmi_driver_init(void) - { -+ int ret; -+ - scmi_bus_init(); - -+ ret = virtio_scmi_init(); -+ if (ret) -+ return ret; -+ - scmi_clock_register(); - scmi_perf_register(); - scmi_power_register(); -@@ -1038,6 +1047,8 @@ static void __exit scmi_driver_exit(void) - scmi_sensors_unregister(); - scmi_system_unregister(); - -+ virtio_scmi_exit(); -+ - platform_driver_unregister(&scmi_driver); - } - module_exit(scmi_driver_exit); -diff --git a/drivers/firmware/arm_scmi/virtio.c b/drivers/firmware/arm_scmi/virtio.c -new file mode 100644 -index 000000000000..f70aa72f34f1 ---- /dev/null -+++ b/drivers/firmware/arm_scmi/virtio.c -@@ -0,0 +1,493 @@ -+// SPDX-License-Identifier: GPL-2.0 -+/* -+ * Virtio Transport driver for Arm System Control and Management Interface -+ * (SCMI). -+ * -+ * Copyright (C) 2020 OpenSynergy. -+ */ -+ -+/** -+ * DOC: Theory of Operation -+ * -+ * The scmi-virtio transport implements a driver for the virtio SCMI device -+ * proposed in virtio spec patch v5[1]. -+ * -+ * There is one tx channel (virtio cmdq, A2P channel) and at most one rx -+ * channel (virtio eventq, P2A channel). Each channel is implemented through a -+ * virtqueue. Access to each virtqueue is protected by a spinlock. -+ * -+ * This SCMI transport uses the scmi_xfer tx/rx buffers for data exchange with -+ * the virtio device to avoid maintenance of additional buffers. -+ * -+ * [1] https://lists.oasis-open.org/archives/virtio-comment/202005/msg00096.html -+ */ -+ -+#include <linux/errno.h> -+#include <linux/of.h> -+#include <linux/of_platform.h> -+#include <linux/platform_device.h> -+#include <linux/module.h> -+#include <linux/slab.h> -+#include <linux/virtio.h> -+#include <linux/virtio_config.h> -+#include <uapi/linux/virtio_ids.h> -+#include <uapi/linux/virtio_scmi.h> -+ -+#include "common.h" -+ -+#define VIRTIO_SCMI_MAX_MSG_SIZE 128 /* Value may be increased. */ -+#define DESCR_PER_TX_MSG 2 -+ -+struct scmi_vio_channel { -+ spinlock_t lock; -+ struct virtqueue *vqueue; -+ struct scmi_chan_info *cinfo; -+ u8 is_rx; -+}; -+ -+union virtio_scmi_input { -+ __virtio32 hdr; -+ struct virtio_scmi_response response; -+ struct virtio_scmi_notification notification; -+}; -+ -+struct scmi_vio_msg { -+ struct virtio_scmi_request *request; -+ union virtio_scmi_input *input; -+ u8 completed; -+}; -+ -+static int scmi_vio_populate_vq_rx(struct scmi_vio_channel *vioch, -+ struct scmi_xfer *xfer) -+{ -+ struct scatterlist sg_in; -+ struct scmi_vio_msg *msg = xfer->extra_data; -+ int rc; -+ -+ msg->completed = false; -+ -+ sg_init_one(&sg_in, msg->input, -+ sizeof(*msg->input) + VIRTIO_SCMI_MAX_MSG_SIZE); -+ -+ rc = virtqueue_add_inbuf(vioch->vqueue, &sg_in, 1, xfer, GFP_ATOMIC); -+ if (rc) -+ dev_err(vioch->cinfo->dev, "%s() rc=%d\n", __func__, rc); -+ else -+ virtqueue_kick(vioch->vqueue); -+ -+ return rc; -+} -+ -+static void scmi_vio_complete_cb(struct virtqueue *vqueue) -+{ -+ struct scmi_vio_channel *vioch = vqueue->priv; -+ unsigned long iflags; -+ unsigned int length; -+ -+ spin_lock_irqsave(&vioch->lock, iflags); -+ -+ do { -+ struct scmi_xfer *xfer; -+ -+ virtqueue_disable_cb(vqueue); -+ -+ while ((xfer = virtqueue_get_buf(vqueue, &length))) { -+ struct scmi_vio_msg *msg = xfer->extra_data; -+ u32 msg_hdr = -+ virtio32_to_cpu(vqueue->vdev, msg->input->hdr); -+ u8 msg_type = MSG_XTRACT_TYPE(msg_hdr); -+ -+ if (!vioch->is_rx) { /* tx queue response */ -+ msg->completed = true; -+ xfer->rx.len = -+ length - sizeof(msg->input->response); -+ if (!xfer->hdr.poll_completion) -+ scmi_rx_callback(vioch->cinfo, msg_hdr); -+ continue; -+ } -+ -+ /* rx queue - notification or delayed response */ -+ switch (msg_type) { -+ case MSG_TYPE_NOTIFICATION: -+ xfer->rx.len = length - -+ sizeof(msg->input->notification); -+ xfer->rx.buf = msg->input->notification.data; -+ break; -+ case MSG_TYPE_DELAYED_RESP: -+ xfer->rx.len = -+ length - sizeof(msg->input->response); -+ xfer->rx.buf = msg->input->response.data; -+ break; -+ default: -+ dev_warn_once(vioch->cinfo->dev, -+ "rx: unknown message_type %d\n", -+ msg_type); -+ scmi_vio_populate_vq_rx(vioch, xfer); -+ continue; -+ } -+ -+ scmi_rx_callback(vioch->cinfo, msg_hdr); -+ scmi_vio_populate_vq_rx(vioch, xfer); -+ } -+ -+ if (unlikely(virtqueue_is_broken(vqueue))) -+ break; -+ } while (!virtqueue_enable_cb(vqueue)); -+ -+ spin_unlock_irqrestore(&vioch->lock, iflags); -+} -+ -+static const char *const scmi_vio_vqueue_names[] = { "tx", "rx" }; -+ -+static vq_callback_t *scmi_vio_complete_callbacks[] = { -+ scmi_vio_complete_cb, -+ scmi_vio_complete_cb -+}; -+ -+static int scmi_vio_match_any_dev(struct device *dev, const void *data) -+{ -+ (void)dev; -+ (void)data; -+ -+ return 1; -+} -+ -+static struct virtio_driver virtio_scmi_driver; /* Forward declaration */ -+ -+static int virtio_link_supplier(struct device *dev) -+{ -+ struct device *vdev = driver_find_device( -+ &virtio_scmi_driver.driver, NULL, NULL, scmi_vio_match_any_dev); -+ -+ if (!vdev) { -+ dev_notice_once( -+ dev, -+ "Deferring probe after not finding a bound scmi-virtio device\n"); -+ return -EPROBE_DEFER; -+ } -+ -+ /* -+ * Add plain device link for completeness. It might have no effect -+ * beyond sysfs. -+ */ -+ if (!device_link_add(dev, vdev, DL_FLAG_AUTOREMOVE_CONSUMER)) { -+ put_device(vdev); -+ dev_err(dev, "Adding link to supplier virtio device failed\n"); -+ return -ECANCELED; -+ } -+ -+ put_device(vdev); -+ return scmi_set_transport_info(dev, dev_to_virtio(vdev)); -+} -+ -+static bool virtio_chan_available(struct device *dev, int idx) -+{ -+ struct virtio_device *vdev; -+ struct scmi_vio_channel **vioch; -+ -+ /* scmi-virtio doesn't support per-protocol channels */ -+ if (is_scmi_protocol_device(dev)) -+ return false; -+ -+ vdev = scmi_get_transport_info(dev); -+ if (!vdev) -+ return false; -+ -+ vioch = vdev->priv; -+ if (!vioch) -+ return false; -+ -+ return vioch[idx] && vioch[idx]->vqueue; -+} -+ -+static int virtio_chan_setup(struct scmi_chan_info *cinfo, struct device *dev, -+ bool tx) -+{ -+ struct virtio_device *vdev; -+ struct scmi_vio_channel **vioch; -+ int vioch_index = tx ? VIRTIO_SCMI_VQ_TX : VIRTIO_SCMI_VQ_RX; -+ -+ /* scmi-virtio doesn't support per-protocol channels */ -+ if (is_scmi_protocol_device(dev)) -+ return -1; -+ -+ vdev = scmi_get_transport_info(dev); -+ if (!vdev) -+ return -1; -+ -+ vioch = vdev->priv; -+ if (!vioch) { -+ dev_err(dev, "Data from scmi-virtio probe not found\n"); -+ return -1; -+ } -+ cinfo->transport_info = vioch[vioch_index]; -+ vioch[vioch_index]->cinfo = cinfo; -+ -+ return 0; -+} -+ -+static int virtio_chan_free(int id, void *p, void *data) -+{ -+ struct scmi_chan_info *cinfo = p; -+ struct scmi_vio_channel *vioch = cinfo->transport_info; -+ -+ if (vioch) { -+ cinfo->transport_info = NULL; -+ kfree(vioch); -+ } -+ -+ scmi_free_channel(cinfo, data, id); -+ return 0; -+} -+ -+static int virtio_get_max_msg(bool tx, struct scmi_chan_info *base_cinfo, -+ int *max_msg) -+{ -+ struct scmi_vio_channel *vioch = base_cinfo->transport_info; -+ -+ *max_msg = virtqueue_get_vring_size(vioch->vqueue); -+ -+ /* Tx messages need multiple descriptors. */ -+ if (tx) -+ *max_msg /= DESCR_PER_TX_MSG; -+ -+ if (*max_msg > MSG_TOKEN_MAX) { -+ dev_notice( -+ base_cinfo->dev, -+ "Only %ld messages can be pending simultaneously, while the virtqueue could hold %d\n", -+ MSG_TOKEN_MAX, *max_msg); -+ *max_msg = MSG_TOKEN_MAX; -+ } -+ -+ return 0; -+} -+ -+static int virtio_xfer_init_buffers(struct scmi_chan_info *cinfo, -+ struct scmi_xfer *xfer, int max_msg_size) -+{ -+ struct scmi_vio_channel *vioch = cinfo->transport_info; -+ struct scmi_vio_msg *msg; -+ -+ msg = devm_kzalloc(cinfo->dev, sizeof(*msg), GFP_KERNEL); -+ if (!msg) -+ return -ENOMEM; -+ -+ xfer->extra_data = msg; -+ -+ if (vioch->is_rx) { -+ int rc; -+ unsigned long iflags; -+ -+ msg->input = devm_kzalloc(cinfo->dev, -+ sizeof(*msg->input) + max_msg_size, -+ GFP_KERNEL); -+ if (!msg->input) -+ return -ENOMEM; -+ -+ /* -+ * xfer->rx.buf will be set to notification or delayed response -+ * specific values in the receive callback, according to the -+ * type of the received message. -+ */ -+ -+ spin_lock_irqsave(&vioch->lock, iflags); -+ rc = scmi_vio_populate_vq_rx(vioch, xfer); -+ spin_unlock_irqrestore(&vioch->lock, iflags); -+ if (rc) -+ return rc; -+ } else { -+ msg->request = -+ devm_kzalloc(cinfo->dev, -+ sizeof(*msg->request) + max_msg_size, -+ GFP_KERNEL); -+ if (!msg->request) -+ return -ENOMEM; -+ -+ xfer->tx.buf = msg->request->data; -+ -+ msg->input = devm_kzalloc( -+ cinfo->dev, sizeof(msg->input->response) + max_msg_size, -+ GFP_KERNEL); -+ if (!msg->input) -+ return -ENOMEM; -+ -+ xfer->rx.buf = msg->input->response.data; -+ } -+ -+ return 0; -+} -+ -+static int scmi_vio_send(struct scmi_vio_channel *vioch, struct scmi_xfer *xfer) -+{ -+ struct scatterlist sg_out; -+ struct scatterlist sg_in; -+ struct scatterlist *sgs[DESCR_PER_TX_MSG] = { &sg_out, &sg_in }; -+ struct scmi_vio_msg *msg = xfer->extra_data; -+ unsigned long iflags; -+ int rc; -+ -+ msg->completed = false; -+ -+ sg_init_one(&sg_out, msg->request, -+ sizeof(*msg->request) + xfer->tx.len); -+ sg_init_one(&sg_in, &msg->input->response, -+ sizeof(msg->input->response) + xfer->rx.len); -+ -+ spin_lock_irqsave(&vioch->lock, iflags); -+ rc = virtqueue_add_sgs(vioch->vqueue, sgs, 1, 1, xfer, GFP_ATOMIC); -+ if (rc) -+ dev_err(vioch->cinfo->dev, "%s() rc=%d\n", __func__, rc); -+ else -+ virtqueue_kick(vioch->vqueue); -+ spin_unlock_irqrestore(&vioch->lock, iflags); -+ -+ return rc; -+} -+ -+static int virtio_send_message(struct scmi_chan_info *cinfo, -+ struct scmi_xfer *xfer) -+{ -+ uint32_t hdr; -+ struct scmi_vio_channel *vioch = cinfo->transport_info; -+ struct virtio_device *vdev = vioch->vqueue->vdev; -+ struct scmi_vio_msg *msg = xfer->extra_data; -+ -+ hdr = pack_scmi_header(&xfer->hdr); -+ -+ msg->request->hdr = cpu_to_virtio32(vdev, hdr); -+ -+ return scmi_vio_send(vioch, xfer); -+} -+ -+static void virtio_fetch_response(struct scmi_chan_info *cinfo, -+ struct scmi_xfer *xfer) -+{ -+ struct scmi_vio_channel *vioch = cinfo->transport_info; -+ struct scmi_vio_msg *msg = xfer->extra_data; -+ -+ xfer->hdr.status = virtio32_to_cpu(vioch->vqueue->vdev, -+ msg->input->response.status); -+} -+ -+static void dummy_fetch_notification(struct scmi_chan_info *cinfo, -+ size_t max_len, struct scmi_xfer *xfer) -+{ -+ (void)cinfo; -+ (void)max_len; -+ (void)xfer; -+} -+ -+static void dummy_clear_channel(struct scmi_chan_info *cinfo) -+{ -+ (void)cinfo; -+} -+ -+static bool virtio_poll_done(struct scmi_chan_info *cinfo, -+ struct scmi_xfer *xfer) -+{ -+ struct scmi_vio_channel *vioch = cinfo->transport_info; -+ struct scmi_vio_msg *msg = xfer->extra_data; -+ unsigned long iflags; -+ bool completed; -+ -+ spin_lock_irqsave(&vioch->lock, iflags); -+ completed = msg->completed; -+ spin_unlock_irqrestore(&vioch->lock, iflags); -+ -+ return 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, -+ .get_max_msg = virtio_get_max_msg, -+ .send_message = virtio_send_message, -+ .fetch_response = virtio_fetch_response, -+ .fetch_notification = dummy_fetch_notification, -+ .clear_channel = dummy_clear_channel, -+ .poll_done = virtio_poll_done, -+ .xfer_init_buffers = virtio_xfer_init_buffers, -+}; -+ -+const struct scmi_desc scmi_virtio_desc = { -+ .ops = &scmi_virtio_ops, -+ .max_rx_timeout_ms = 60000, /* for non-realtime virtio devices */ -+ .max_msg = 0, /* overridden by virtio_get_max_msg() */ -+ .max_msg_size = VIRTIO_SCMI_MAX_MSG_SIZE, -+}; -+ -+static int scmi_vio_probe(struct virtio_device *vdev) -+{ -+ struct device *dev = &vdev->dev; -+ struct scmi_vio_channel **vioch; -+ bool have_vq_rx; -+ int vq_cnt; -+ int i; -+ struct virtqueue *vqs[VIRTIO_SCMI_VQ_MAX_CNT]; -+ -+ vioch = devm_kcalloc(dev, VIRTIO_SCMI_VQ_MAX_CNT, sizeof(*vioch), -+ GFP_KERNEL); -+ if (!vioch) -+ return -ENOMEM; -+ -+ have_vq_rx = virtio_has_feature(vdev, VIRTIO_SCMI_F_P2A_CHANNELS); -+ vq_cnt = have_vq_rx ? VIRTIO_SCMI_VQ_MAX_CNT : 1; -+ -+ for (i = 0; i < vq_cnt; i++) { -+ vioch[i] = devm_kzalloc(dev, sizeof(**vioch), GFP_KERNEL); -+ if (!vioch[i]) -+ return -ENOMEM; -+ } -+ -+ if (have_vq_rx) -+ vioch[VIRTIO_SCMI_VQ_RX]->is_rx = true; -+ -+ if (virtio_find_vqs(vdev, vq_cnt, vqs, scmi_vio_complete_callbacks, -+ scmi_vio_vqueue_names, NULL)) { -+ dev_err(dev, "Failed to get %d virtqueue(s)\n", vq_cnt); -+ return -1; -+ } -+ dev_info(dev, "Found %d virtqueue(s)\n", vq_cnt); -+ -+ for (i = 0; i < vq_cnt; i++) { -+ spin_lock_init(&vioch[i]->lock); -+ vioch[i]->vqueue = vqs[i]; -+ vioch[i]->vqueue->priv = vioch[i]; -+ } -+ -+ vdev->priv = vioch; -+ -+ virtio_device_ready(vdev); -+ -+ return 0; -+} -+ -+static unsigned int features[] = { -+ VIRTIO_SCMI_F_P2A_CHANNELS, -+}; -+ -+static const struct virtio_device_id id_table[] = { -+ { VIRTIO_ID_SCMI, VIRTIO_DEV_ANY_ID }, -+ { 0 } -+}; -+ -+static struct virtio_driver virtio_scmi_driver = { -+ .driver.name = "scmi-virtio", -+ .driver.owner = THIS_MODULE, -+ .feature_table = features, -+ .feature_table_size = ARRAY_SIZE(features), -+ .id_table = id_table, -+ .probe = scmi_vio_probe, -+}; -+ -+int __init virtio_scmi_init(void) -+{ -+ return register_virtio_driver(&virtio_scmi_driver); -+} -+ -+void __exit virtio_scmi_exit(void) -+{ -+ unregister_virtio_driver(&virtio_scmi_driver); -+} -diff --git a/include/uapi/linux/virtio_ids.h b/include/uapi/linux/virtio_ids.h -index bc740d6d2259..287daba2abdb 100644 ---- a/include/uapi/linux/virtio_ids.h -+++ b/include/uapi/linux/virtio_ids.h -@@ -49,5 +49,6 @@ - #define VIRTIO_ID_FS 26 /* virtio filesystem */ - #define VIRTIO_ID_PMEM 27 /* virtio pmem */ - #define VIRTIO_ID_MAC80211_HWSIM 29 /* virtio mac80211-hwsim */ -+#define VIRTIO_ID_SCMI 32 /* virtio SCMI */ - - #endif /* _LINUX_VIRTIO_IDS_H */ -diff --git a/include/uapi/linux/virtio_scmi.h b/include/uapi/linux/virtio_scmi.h -new file mode 100644 -index 000000000000..9f21b3dbbfe2 ---- /dev/null -+++ b/include/uapi/linux/virtio_scmi.h -@@ -0,0 +1,41 @@ -+/* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) */ -+/* -+ * Copyright (C) 2020 OpenSynergy GmbH -+ */ -+ -+#ifndef _UAPI_LINUX_VIRTIO_SCMI_H -+#define _UAPI_LINUX_VIRTIO_SCMI_H -+ -+#include <linux/virtio_types.h> -+ -+/* Feature bits */ -+ -+/* Device implements some SCMI notifications, or delayed responses. */ -+#define VIRTIO_SCMI_F_P2A_CHANNELS 0 -+ -+/* Device implements any SCMI statistics shared memory region */ -+#define VIRTIO_SCMI_F_SHARED_MEMORY 1 -+ -+/* Virtqueues */ -+ -+#define VIRTIO_SCMI_VQ_TX 0 /* cmdq */ -+#define VIRTIO_SCMI_VQ_RX 1 /* eventq */ -+#define VIRTIO_SCMI_VQ_MAX_CNT 2 -+ -+struct virtio_scmi_request { -+ __virtio32 hdr; -+ __u8 data[]; -+}; -+ -+struct virtio_scmi_response { -+ __virtio32 hdr; -+ __virtio32 status; -+ __u8 data[]; -+}; -+ -+struct virtio_scmi_notification { -+ __virtio32 hdr; -+ __u8 data[]; -+}; -+ -+#endif /* _UAPI_LINUX_VIRTIO_SCMI_H */ |