diff options
Diffstat (limited to 'drivers/rpmsg')
| -rw-r--r-- | drivers/rpmsg/Kconfig | 9 | ||||
| -rw-r--r-- | drivers/rpmsg/Makefile | 1 | ||||
| -rw-r--r-- | drivers/rpmsg/mtk_rpmsg.c | 414 |
3 files changed, 424 insertions, 0 deletions
diff --git a/drivers/rpmsg/Kconfig b/drivers/rpmsg/Kconfig index 709276540ef1..a9108ff563dc 100644 --- a/drivers/rpmsg/Kconfig +++ b/drivers/rpmsg/Kconfig @@ -15,6 +15,15 @@ config RPMSG_CHAR in /dev. They make it possible for user-space programs to send and receive rpmsg packets. +config RPMSG_MTK_SCP + tristate "MediaTek SCP" + depends on MTK_SCP + select RPMSG + help + Say y here to enable support providing communication channels to + remote processors in MediaTek platforms. + This use IPI and IPC to communicate with remote processors. + config RPMSG_QCOM_GLINK_NATIVE tristate select RPMSG diff --git a/drivers/rpmsg/Makefile b/drivers/rpmsg/Makefile index 9aa859502d27..ae92a7fb08f6 100644 --- a/drivers/rpmsg/Makefile +++ b/drivers/rpmsg/Makefile @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_RPMSG) += rpmsg_core.o obj-$(CONFIG_RPMSG_CHAR) += rpmsg_char.o +obj-$(CONFIG_RPMSG_MTK_SCP) += mtk_rpmsg.o obj-$(CONFIG_RPMSG_QCOM_GLINK_RPM) += qcom_glink_rpm.o obj-$(CONFIG_RPMSG_QCOM_GLINK_NATIVE) += qcom_glink_native.o obj-$(CONFIG_RPMSG_QCOM_GLINK_SMEM) += qcom_glink_smem.o diff --git a/drivers/rpmsg/mtk_rpmsg.c b/drivers/rpmsg/mtk_rpmsg.c new file mode 100644 index 000000000000..232aa4e40133 --- /dev/null +++ b/drivers/rpmsg/mtk_rpmsg.c @@ -0,0 +1,414 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Copyright 2019 Google LLC. + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/remoteproc.h> +#include <linux/rpmsg/mtk_rpmsg.h> +#include <linux/workqueue.h> + +#include "rpmsg_internal.h" + +struct mtk_rpmsg_rproc_subdev { + struct platform_device *pdev; + struct mtk_rpmsg_info *info; + struct rpmsg_endpoint *ns_ept; + struct rproc_subdev subdev; + + struct work_struct register_work; + struct list_head channels; + struct mutex channels_lock; +}; + +#define to_mtk_subdev(d) container_of(d, struct mtk_rpmsg_rproc_subdev, subdev) + +struct mtk_rpmsg_channel_info { + struct rpmsg_channel_info info; + bool registered; + struct list_head list; +}; + +/** + * struct rpmsg_ns_msg - dynamic name service announcement message + * @name: name of remote service that is published + * @addr: address of remote service that is published + * + * This message is sent across to publish a new service. When we receive these + * messages, an appropriate rpmsg channel (i.e device) is created. In turn, the + * ->probe() handler of the appropriate rpmsg driver will be invoked + * (if/as-soon-as one is registered). + */ +struct rpmsg_ns_msg { + char name[RPMSG_NAME_SIZE]; + u32 addr; +} __packed; + +struct mtk_rpmsg_device { + struct rpmsg_device rpdev; + struct mtk_rpmsg_rproc_subdev *mtk_subdev; +}; + +struct mtk_rpmsg_endpoint { + struct rpmsg_endpoint ept; + struct mtk_rpmsg_rproc_subdev *mtk_subdev; +}; + +#define to_mtk_rpmsg_device(r) container_of(r, struct mtk_rpmsg_device, rpdev) +#define to_mtk_rpmsg_endpoint(r) container_of(r, struct mtk_rpmsg_endpoint, ept) + +static const struct rpmsg_endpoint_ops mtk_rpmsg_endpoint_ops; + +static void __mtk_ept_release(struct kref *kref) +{ + struct rpmsg_endpoint *ept = container_of(kref, struct rpmsg_endpoint, + refcount); + kfree(to_mtk_rpmsg_endpoint(ept)); +} + +static void mtk_rpmsg_ipi_handler(void *data, unsigned int len, void *priv) +{ + struct mtk_rpmsg_endpoint *mept = priv; + struct rpmsg_endpoint *ept = &mept->ept; + int ret; + + ret = (*ept->cb)(ept->rpdev, data, len, ept->priv, ept->addr); + if (ret) + dev_warn(&ept->rpdev->dev, "rpmsg handler return error = %d", + ret); +} + +static struct rpmsg_endpoint * +__mtk_create_ept(struct mtk_rpmsg_rproc_subdev *mtk_subdev, + struct rpmsg_device *rpdev, rpmsg_rx_cb_t cb, void *priv, + u32 id) +{ + struct mtk_rpmsg_endpoint *mept; + struct rpmsg_endpoint *ept; + struct platform_device *pdev = mtk_subdev->pdev; + int ret; + + mept = kzalloc(sizeof(*mept), GFP_KERNEL); + if (!mept) + return NULL; + mept->mtk_subdev = mtk_subdev; + + ept = &mept->ept; + kref_init(&ept->refcount); + + ept->rpdev = rpdev; + ept->cb = cb; + ept->priv = priv; + ept->ops = &mtk_rpmsg_endpoint_ops; + ept->addr = id; + + ret = mtk_subdev->info->register_ipi(pdev, id, mtk_rpmsg_ipi_handler, + mept); + if (ret) { + dev_err(&pdev->dev, "IPI register failed, id = %d", id); + kref_put(&ept->refcount, __mtk_ept_release); + return NULL; + } + + return ept; +} + +static struct rpmsg_endpoint * +mtk_rpmsg_create_ept(struct rpmsg_device *rpdev, rpmsg_rx_cb_t cb, void *priv, + struct rpmsg_channel_info chinfo) +{ + struct mtk_rpmsg_rproc_subdev *mtk_subdev = + to_mtk_rpmsg_device(rpdev)->mtk_subdev; + + return __mtk_create_ept(mtk_subdev, rpdev, cb, priv, chinfo.src); +} + +static void mtk_rpmsg_destroy_ept(struct rpmsg_endpoint *ept) +{ + struct mtk_rpmsg_rproc_subdev *mtk_subdev = + to_mtk_rpmsg_endpoint(ept)->mtk_subdev; + + mtk_subdev->info->unregister_ipi(mtk_subdev->pdev, ept->addr); + kref_put(&ept->refcount, __mtk_ept_release); +} + +static int mtk_rpmsg_send(struct rpmsg_endpoint *ept, void *data, int len) +{ + struct mtk_rpmsg_rproc_subdev *mtk_subdev = + to_mtk_rpmsg_endpoint(ept)->mtk_subdev; + + return mtk_subdev->info->send_ipi(mtk_subdev->pdev, ept->addr, data, + len, 0); +} + +static int mtk_rpmsg_trysend(struct rpmsg_endpoint *ept, void *data, int len) +{ + struct mtk_rpmsg_rproc_subdev *mtk_subdev = + to_mtk_rpmsg_endpoint(ept)->mtk_subdev; + + /* + * TODO: This currently is same as mtk_rpmsg_send, and wait until SCP + * received the last command. + */ + return mtk_subdev->info->send_ipi(mtk_subdev->pdev, ept->addr, data, + len, 0); +} + +static const struct rpmsg_endpoint_ops mtk_rpmsg_endpoint_ops = { + .destroy_ept = mtk_rpmsg_destroy_ept, + .send = mtk_rpmsg_send, + .trysend = mtk_rpmsg_trysend, +}; + +static void mtk_rpmsg_release_device(struct device *dev) +{ + struct rpmsg_device *rpdev = to_rpmsg_device(dev); + struct mtk_rpmsg_device *mdev = to_mtk_rpmsg_device(rpdev); + + kfree(mdev); +} + +static const struct rpmsg_device_ops mtk_rpmsg_device_ops = { + .create_ept = mtk_rpmsg_create_ept, +}; + +static struct device_node * +mtk_rpmsg_match_device_subnode(struct device_node *node, const char *channel) +{ + struct device_node *child; + const char *name; + int ret; + + for_each_available_child_of_node(node, child) { + ret = of_property_read_string(child, "mtk,rpmsg-name", &name); + if (ret) + continue; + + if (strcmp(name, channel) == 0) + return child; + } + + return NULL; +} + +static int mtk_rpmsg_register_device(struct mtk_rpmsg_rproc_subdev *mtk_subdev, + struct rpmsg_channel_info *info) +{ + struct rpmsg_device *rpdev; + struct mtk_rpmsg_device *mdev; + struct platform_device *pdev = mtk_subdev->pdev; + int ret; + + mdev = kzalloc(sizeof(*mdev), GFP_KERNEL); + if (!mdev) + return -ENOMEM; + + mdev->mtk_subdev = mtk_subdev; + + rpdev = &mdev->rpdev; + rpdev->ops = &mtk_rpmsg_device_ops; + rpdev->src = info->src; + rpdev->dst = info->dst; + strscpy(rpdev->id.name, info->name, RPMSG_NAME_SIZE); + + rpdev->dev.of_node = + mtk_rpmsg_match_device_subnode(pdev->dev.of_node, info->name); + rpdev->dev.parent = &pdev->dev; + rpdev->dev.release = mtk_rpmsg_release_device; + + ret = rpmsg_register_device(rpdev); + if (ret) { + kfree(mdev); + return ret; + } + + return 0; +} + +static void mtk_register_device_work_function(struct work_struct *register_work) +{ + struct mtk_rpmsg_rproc_subdev *subdev = container_of( + register_work, struct mtk_rpmsg_rproc_subdev, register_work); + struct platform_device *pdev = subdev->pdev; + struct mtk_rpmsg_channel_info *info; + int ret; + + mutex_lock(&subdev->channels_lock); + list_for_each_entry(info, &subdev->channels, list) { + if (info->registered) + continue; + + ret = mtk_rpmsg_register_device(subdev, &info->info); + if (ret) { + dev_err(&pdev->dev, "Can't create rpmsg_device\n"); + continue; + } + + info->registered = true; + } + mutex_unlock(&subdev->channels_lock); +} + +static int mtk_rpmsg_create_device(struct mtk_rpmsg_rproc_subdev *mtk_subdev, + char *name, u32 addr) +{ + struct mtk_rpmsg_channel_info *info; + + info = kzalloc(sizeof(*info), GFP_KERNEL); + if (!info) + return -ENOMEM; + + strscpy(info->info.name, name, RPMSG_NAME_SIZE); + info->info.src = addr; + info->info.dst = RPMSG_ADDR_ANY; + mutex_lock(&mtk_subdev->channels_lock); + list_add(&info->list, &mtk_subdev->channels); + mutex_unlock(&mtk_subdev->channels_lock); + + schedule_work(&mtk_subdev->register_work); + return 0; +} + +static int mtk_rpmsg_ns_cb(struct rpmsg_device *rpdev, void *data, int len, + void *priv, u32 src) +{ + struct rpmsg_ns_msg *msg = data; + struct mtk_rpmsg_rproc_subdev *mtk_subdev = priv; + struct device *dev = &mtk_subdev->pdev->dev; + + int ret; + + if (len != sizeof(*msg)) { + dev_err(dev, "malformed ns msg (%d)\n", len); + return -EINVAL; + } + + /* + * the name service ept does _not_ belong to a real rpmsg channel, + * and is handled by the rpmsg bus itself. + * for sanity reasons, make sure a valid rpdev has _not_ sneaked + * in somehow. + */ + if (rpdev) { + dev_err(dev, "anomaly: ns ept has an rpdev handle\n"); + return -EINVAL; + } + + /* don't trust the remote processor for null terminating the name */ + msg->name[RPMSG_NAME_SIZE - 1] = '\0'; + + dev_info(dev, "creating channel %s addr 0x%x\n", msg->name, msg->addr); + + ret = mtk_rpmsg_create_device(mtk_subdev, msg->name, msg->addr); + if (ret) { + dev_err(dev, "create rpmsg device failed\n"); + return ret; + } + + return 0; +} + +static int mtk_rpmsg_prepare(struct rproc_subdev *subdev) +{ + struct mtk_rpmsg_rproc_subdev *mtk_subdev = to_mtk_subdev(subdev); + + /* a dedicated endpoint handles the name service msgs */ + if (mtk_subdev->info->ns_ipi_id >= 0) { + mtk_subdev->ns_ept = + __mtk_create_ept(mtk_subdev, NULL, mtk_rpmsg_ns_cb, + mtk_subdev, + mtk_subdev->info->ns_ipi_id); + if (!mtk_subdev->ns_ept) { + dev_err(&mtk_subdev->pdev->dev, + "failed to create name service endpoint\n"); + return -ENOMEM; + } + } + + return 0; +} + +static void mtk_rpmsg_unprepare(struct rproc_subdev *subdev) +{ + struct mtk_rpmsg_rproc_subdev *mtk_subdev = to_mtk_subdev(subdev); + + if (mtk_subdev->ns_ept) { + mtk_rpmsg_destroy_ept(mtk_subdev->ns_ept); + mtk_subdev->ns_ept = NULL; + } +} + +static void mtk_rpmsg_stop(struct rproc_subdev *subdev, bool crashed) +{ + struct mtk_rpmsg_channel_info *info, *next; + struct mtk_rpmsg_rproc_subdev *mtk_subdev = to_mtk_subdev(subdev); + struct device *dev = &mtk_subdev->pdev->dev; + + /* + * Destroy the name service endpoint here, to avoid new channel being + * created after the rpmsg_unregister_device loop below. + */ + if (mtk_subdev->ns_ept) { + mtk_rpmsg_destroy_ept(mtk_subdev->ns_ept); + mtk_subdev->ns_ept = NULL; + } + + cancel_work_sync(&mtk_subdev->register_work); + + mutex_lock(&mtk_subdev->channels_lock); + list_for_each_entry(info, &mtk_subdev->channels, list) { + if (!info->registered) + continue; + if (rpmsg_unregister_device(dev, &info->info)) { + dev_warn( + dev, + "rpmsg_unregister_device failed for %s.%d.%d\n", + info->info.name, info->info.src, + info->info.dst); + } + } + + list_for_each_entry_safe(info, next, + &mtk_subdev->channels, list) { + list_del(&info->list); + kfree(info); + } + mutex_unlock(&mtk_subdev->channels_lock); +} + +struct rproc_subdev * +mtk_rpmsg_create_rproc_subdev(struct platform_device *pdev, + struct mtk_rpmsg_info *info) +{ + struct mtk_rpmsg_rproc_subdev *mtk_subdev; + + mtk_subdev = kzalloc(sizeof(*mtk_subdev), GFP_KERNEL); + if (!mtk_subdev) + return NULL; + + mtk_subdev->pdev = pdev; + mtk_subdev->subdev.prepare = mtk_rpmsg_prepare; + mtk_subdev->subdev.stop = mtk_rpmsg_stop; + mtk_subdev->subdev.unprepare = mtk_rpmsg_unprepare; + mtk_subdev->info = info; + INIT_LIST_HEAD(&mtk_subdev->channels); + INIT_WORK(&mtk_subdev->register_work, + mtk_register_device_work_function); + mutex_init(&mtk_subdev->channels_lock); + + return &mtk_subdev->subdev; +} +EXPORT_SYMBOL_GPL(mtk_rpmsg_create_rproc_subdev); + +void mtk_rpmsg_destroy_rproc_subdev(struct rproc_subdev *subdev) +{ + struct mtk_rpmsg_rproc_subdev *mtk_subdev = to_mtk_subdev(subdev); + + kfree(mtk_subdev); +} +EXPORT_SYMBOL_GPL(mtk_rpmsg_destroy_rproc_subdev); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("MediaTek scp rpmsg driver"); |