Add a simple rpmsg support for mt8183 SCP, that use IPI / IPC directly. Lots of TODO, and I'm not sure on all file / type / variable namings.
Signed-off-by: Pi-Hsun Shih <[email protected]> --- Changes from v2: - Unregiser IPI handler on unprepare. - Lock the channel list on operations. - Move SCP_IPI_NS_SERVICE to 0xFF. Changes from v1: - Do cleanup properly in mtk_rpmsg.c, which also removes the problem of short-lived work items. - Fix several issues checkpatch found. --- drivers/remoteproc/mtk_common.h | 3 + drivers/remoteproc/mtk_scp.c | 29 +- drivers/remoteproc/mtk_scp_ipi.c | 5 +- drivers/rpmsg/Kconfig | 8 + drivers/rpmsg/Makefile | 1 + drivers/rpmsg/mtk_rpmsg.c | 395 ++++++++++++++++++++++++++ include/linux/platform_data/mtk_scp.h | 6 +- include/linux/rpmsg/mtk_rpmsg.h | 35 +++ 8 files changed, 475 insertions(+), 7 deletions(-) create mode 100644 drivers/rpmsg/mtk_rpmsg.c create mode 100644 include/linux/rpmsg/mtk_rpmsg.h diff --git a/drivers/remoteproc/mtk_common.h b/drivers/remoteproc/mtk_common.h index 5b682e7a890b27..13a7088cbeb6e6 100644 --- a/drivers/remoteproc/mtk_common.h +++ b/drivers/remoteproc/mtk_common.h @@ -53,6 +53,9 @@ struct mtk_scp { void __iomem *cpu_addr; phys_addr_t phys_addr; size_t dram_size; + + struct platform_device *pdev; + struct rproc_subdev *rpmsg_subdev; }; /** diff --git a/drivers/remoteproc/mtk_scp.c b/drivers/remoteproc/mtk_scp.c index 37325a92464524..0987e85e9aaeb4 100644 --- a/drivers/remoteproc/mtk_scp.c +++ b/drivers/remoteproc/mtk_scp.c @@ -13,6 +13,7 @@ #include <linux/platform_data/mtk_scp.h> #include <linux/platform_device.h> #include <linux/remoteproc.h> +#include <linux/rpmsg/mtk_rpmsg.h> #include "mtk_common.h" #include "remoteproc_internal.h" @@ -299,6 +300,23 @@ static int scp_map_memory_region(struct mtk_scp *scp) return 0; } +static void scp_add_rpmsg_subdev(struct mtk_scp *scp) +{ + scp->rpmsg_subdev = + mtk_rpmsg_create_rproc_subdev(scp->pdev, scp->rproc); + if (scp->rpmsg_subdev) + rproc_add_subdev(scp->rproc, scp->rpmsg_subdev); +} + +static void scp_remove_rpmsg_subdev(struct mtk_scp *scp) +{ + if (scp->rpmsg_subdev) { + rproc_remove_subdev(scp->rproc, scp->rpmsg_subdev); + mtk_rpmsg_destroy_rproc_subdev(scp->rpmsg_subdev); + scp->rpmsg_subdev = NULL; + } +} + static int mtk_scp_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; @@ -322,6 +340,7 @@ static int mtk_scp_probe(struct platform_device *pdev) scp = (struct mtk_scp *)rproc->priv; scp->rproc = rproc; scp->dev = dev; + scp->pdev = pdev; platform_set_drvdata(pdev, scp); res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "sram"); @@ -392,13 +411,16 @@ static int mtk_scp_probe(struct platform_device *pdev) init_waitqueue_head(&scp->run.wq); init_waitqueue_head(&scp->ack_wq); + scp_add_rpmsg_subdev(scp); + ret = rproc_add(rproc); if (ret) - goto destroy_mutex; + goto remove_subdev; - return ret; + return 0; -destroy_mutex: +remove_subdev: + scp_remove_rpmsg_subdev(scp); mutex_destroy(&scp->scp_mutex); free_rproc: rproc_free(rproc); @@ -410,6 +432,7 @@ static int mtk_scp_remove(struct platform_device *pdev) { struct mtk_scp *scp = platform_get_drvdata(pdev); + scp_remove_rpmsg_subdev(scp); rproc_del(scp->rproc); rproc_free(scp->rproc); diff --git a/drivers/remoteproc/mtk_scp_ipi.c b/drivers/remoteproc/mtk_scp_ipi.c index f74acdf68f3867..539f246b9d08f7 100644 --- a/drivers/remoteproc/mtk_scp_ipi.c +++ b/drivers/remoteproc/mtk_scp_ipi.c @@ -67,8 +67,9 @@ int scp_ipi_send(struct platform_device *pdev, int ret; if (WARN(id <= SCP_IPI_INIT || id >= SCP_IPI_MAX || - len > sizeof(send_obj->share_buf) || !buf, - "failed to send ipi message\n")) + id == SCP_IPI_NS_SERVICE || + len > sizeof(send_obj->share_buf) || !buf, + "failed to send ipi message\n")) return -EINVAL; ret = clk_prepare_enable(scp->clk); diff --git a/drivers/rpmsg/Kconfig b/drivers/rpmsg/Kconfig index d0322b41eca54c..31e7eb904fbac0 100644 --- a/drivers/rpmsg/Kconfig +++ b/drivers/rpmsg/Kconfig @@ -15,6 +15,14 @@ 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. + config RPMSG_QCOM_GLINK_NATIVE tristate select RPMSG diff --git a/drivers/rpmsg/Makefile b/drivers/rpmsg/Makefile index 9aa859502d2752..ae92a7fb08f623 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 00000000000000..734bf800acb745 --- /dev/null +++ b/drivers/rpmsg/mtk_rpmsg.c @@ -0,0 +1,395 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Copyright 2018 Google LLC. + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_data/mtk_scp.h> +#include <linux/platform_device.h> +#include <linux/remoteproc.h> +#include <linux/rpmsg/mtk_rpmsg.h> +#include <linux/workqueue.h> + +#include "rpmsg_internal.h" + +/* + * TODO: This is built on top of scp_ipi_register / scp_ipi_send in mtk_scp.h. + * It's probably better to move the implementation of register / send to here + * instead of in remoteproc/mtk_scp_ipi.c + */ +/* + * TODO: Do we need some sort of vring for performance? We may be able to get + * rid of this file if so, but that would require SCP firmware support too. + */ + +struct mtk_rpmsg_device { + struct rpmsg_device rpdev; + struct platform_device *scp_pdev; +}; + +struct mtk_rpmsg_endpoint { + struct rpmsg_endpoint ept; + struct platform_device *scp_pdev; +}; + +/* TODO: Naming is hard... */ +struct mtk_rpmsg_rproc_subdev { + struct rproc *scp_rproc; + struct platform_device *scp_pdev; + struct rpmsg_endpoint *ns_ept; + struct rproc_subdev subdev; + + struct work_struct register_work; + struct list_head channels; + spinlock_t 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; +}; + +/** + * TODO: This is copied from virtio_rpmsg_bus. + * 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, or announce + * about its removal. When we receive these messages, an appropriate + * rpmsg channel (i.e device) is created/destroyed. In turn, the ->probe() + * or ->remove() 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; + +#define to_scp_device(r) container_of(r, struct mtk_rpmsg_device, rpdev) +#define to_scp_endpoint(r) container_of(r, struct mtk_rpmsg_endpoint, ept) + +static const struct rpmsg_endpoint_ops mtk_rpmsg_endpoint_ops; + +static void __ept_release(struct kref *kref) +{ + struct rpmsg_endpoint *ept = container_of(kref, struct rpmsg_endpoint, + refcount); + kfree(to_scp_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; + + /* TODO: What if the cb() returns error? */ + (*ept->cb)(ept->rpdev, data, len, ept->priv, ept->addr); +} + +static struct rpmsg_endpoint * +__rpmsg_create_ept(struct platform_device *scp_pdev, struct rpmsg_device *rpdev, + rpmsg_rx_cb_t cb, void *priv, + u32 id) +{ + struct mtk_rpmsg_endpoint *mept; + struct rpmsg_endpoint *ept; + + int ret; + + mept = kzalloc(sizeof(*mept), GFP_KERNEL); + if (!mept) + return NULL; + mept->scp_pdev = scp_pdev; + + 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 = scp_ipi_register(scp_pdev, id, mtk_rpmsg_ipi_handler, mept); + if (ret) { + dev_err(&scp_pdev->dev, "ipi register failed, id = %d", id); + kref_put(&ept->refcount, __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 platform_device *scp_pdev = to_scp_device(rpdev)->scp_pdev; + /* TODO: Is using src as IPI id "correct"? */ + return __rpmsg_create_ept(scp_pdev, rpdev, cb, priv, chinfo.src); +} + +static const struct rpmsg_device_ops mtk_rpmsg_device_ops = { + .create_ept = mtk_rpmsg_create_ept, +}; + +static void mtk_rpmsg_destroy_ept(struct rpmsg_endpoint *ept) +{ + struct mtk_rpmsg_endpoint *mept = to_scp_endpoint(ept); + + scp_ipi_unregister(mept->scp_pdev, ept->addr); + kref_put(&ept->refcount, __ept_release); +} + +static int __mtk_rpmsg_send(struct mtk_rpmsg_endpoint *mept, void *data, + int len, bool wait) +{ + /* TODO: This currently always wait for SCP to receive last command. */ + return scp_ipi_send(mept->scp_pdev, mept->ept.addr, data, len, 0); +} + +static int mtk_rpmsg_send(struct rpmsg_endpoint *ept, void *data, int len) +{ + struct mtk_rpmsg_endpoint *mept = to_scp_endpoint(ept); + + return __mtk_rpmsg_send(mept, data, len, true); +} + +static int mtk_rpmsg_trysend(struct rpmsg_endpoint *ept, void *data, int len) +{ + struct mtk_rpmsg_endpoint *mept = to_scp_endpoint(ept); + + return __mtk_rpmsg_send(mept, data, len, false); +} + +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_scp_device(rpdev); + + kfree(mdev); +} + +static int mtk_rpmsg_register_device(struct platform_device *scp_pdev, + struct rpmsg_channel_info *info) +{ + struct rpmsg_device *rpdev; + struct mtk_rpmsg_device *mdev; + int ret; + + mdev = kzalloc(sizeof(*mdev), GFP_KERNEL); + if (!mdev) + return -ENOMEM; + + mdev->scp_pdev = scp_pdev; + + rpdev = &mdev->rpdev; + rpdev->ops = &mtk_rpmsg_device_ops; + rpdev->src = info->src; + rpdev->dst = info->dst; + strncpy(rpdev->id.name, info->name, RPMSG_NAME_SIZE); + + rpdev->dev.parent = &scp_pdev->dev; + rpdev->dev.release = mtk_rpmsg_release_device; + + ret = rpmsg_register_device(rpdev); + if (ret) + return ret; + + return 0; +} + +static void mtk_register_device_work_function(struct work_struct *register_work) +{ + struct mtk_rpmsg_rproc_subdev *mtk_subdev = container_of( + register_work, struct mtk_rpmsg_rproc_subdev, register_work); + struct platform_device *scp_pdev = mtk_subdev->scp_pdev; + struct mtk_rpmsg_channel_info *info; + + int ret; + unsigned long flags; + + spin_lock_irqsave(&mtk_subdev->channels_lock, flags); + list_for_each_entry(info, &mtk_subdev->channels, list) { + if (info->registered) + continue; + + spin_unlock_irqrestore(&mtk_subdev->channels_lock, flags); + ret = mtk_rpmsg_register_device(scp_pdev, &info->info); + spin_lock_irqsave(&mtk_subdev->channels_lock, flags); + + if (ret) { + dev_err(&scp_pdev->dev, "Can't create rpmsg_device\n"); + continue; + } + + info->registered = true; + } + spin_unlock_irqrestore(&mtk_subdev->channels_lock, flags); +} + +static int mtk_rpmsg_create_device(struct mtk_rpmsg_rproc_subdev *mtk_subdev, + char *name, u32 addr) +{ + struct mtk_rpmsg_channel_info *info; + unsigned long flags; + + /* This is called in interrupt context from name service callback. */ + info = kzalloc(sizeof(*info), GFP_ATOMIC); + if (!info) + return -ENOMEM; + + strncpy(info->info.name, name, RPMSG_NAME_SIZE); + info->info.src = addr; + info->info.dst = RPMSG_ADDR_ANY; + spin_lock_irqsave(&mtk_subdev->channels_lock, flags); + list_add(&info->list, &mtk_subdev->channels); + spin_unlock_irqrestore(&mtk_subdev->channels_lock, flags); + + 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->scp_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; +} + +int mtk_rpmsg_prepare(struct rproc_subdev *subdev) +{ + struct mtk_rpmsg_rproc_subdev *mtk_subdev; + struct platform_device *scp_pdev; + + mtk_subdev = to_mtk_subdev(subdev); + scp_pdev = mtk_subdev->scp_pdev; + + /* a dedicated endpoint handles the name service msgs */ + mtk_subdev->ns_ept = + __rpmsg_create_ept(scp_pdev, NULL, mtk_rpmsg_ns_cb, mtk_subdev, + SCP_IPI_NS_SERVICE); + if (!mtk_subdev->ns_ept) { + dev_err(&scp_pdev->dev, + "failed to create name service endpoint\n"); + return -ENOMEM; + } + + return 0; +} + +void mtk_rpmsg_unprepare(struct rproc_subdev *subdev) +{ + struct mtk_rpmsg_channel_info *info, *next; + struct device *dev; + struct mtk_rpmsg_rproc_subdev *mtk_subdev = to_mtk_subdev(subdev); + unsigned long flags; + + dev = &mtk_subdev->scp_pdev->dev; + + cancel_work_sync(&mtk_subdev->register_work); + /* + * TODO: It feels like there's still possible race condition for some + * callback to schedule new work after the cancel_work_sync. How's this + * typically handled? + */ + spin_lock_irqsave(&mtk_subdev->channels_lock, flags); + list_for_each_entry(info, &mtk_subdev->channels, list) { + if (!info->registered) + continue; + spin_unlock_irqrestore(&mtk_subdev->channels_lock, flags); + 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); + } + spin_lock_irqsave(&mtk_subdev->channels_lock, flags); + } + + list_for_each_entry_safe(info, next, + &mtk_subdev->channels, list) { + list_del(&info->list); + kfree(info); + } + spin_unlock_irqrestore(&mtk_subdev->channels_lock, flags); + + kref_put(&mtk_subdev->ns_ept->refcount, __ept_release); +} + +struct rproc_subdev * +mtk_rpmsg_create_rproc_subdev(struct platform_device *scp_pdev, + struct rproc *scp_rproc) +{ + struct mtk_rpmsg_rproc_subdev *mtk_subdev; + + mtk_subdev = kzalloc(sizeof(*mtk_subdev), GFP_KERNEL); + if (!mtk_subdev) + return NULL; + + mtk_subdev->scp_pdev = scp_pdev; + mtk_subdev->scp_rproc = scp_rproc; + mtk_subdev->subdev.prepare = mtk_rpmsg_prepare; + mtk_subdev->subdev.unprepare = mtk_rpmsg_unprepare; + INIT_LIST_HEAD(&mtk_subdev->channels); + INIT_WORK(&mtk_subdev->register_work, + mtk_register_device_work_function); + + 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"); diff --git a/include/linux/platform_data/mtk_scp.h b/include/linux/platform_data/mtk_scp.h index 0e999ec319446b..643ef305a9e88d 100644 --- a/include/linux/platform_data/mtk_scp.h +++ b/include/linux/platform_data/mtk_scp.h @@ -22,7 +22,7 @@ typedef void (*scp_ipi_handler_t) (void *data, * command to SCP. * For other IPI below, AP should send the request * to SCP to trigger the interrupt. - * @IPI_MAX: The maximum IPI number + * @SCP_IPI_MAX: The maximum IPI number */ enum scp_ipi_id { @@ -34,9 +34,11 @@ enum scp_ipi_id { SCP_IPI_VENC_VP8, SCP_IPI_MDP, SCP_IPI_CROS_HOST_CMD, - SCP_IPI_MAX, }; +#define SCP_IPI_NS_SERVICE 0xFF +#define SCP_IPI_MAX 0x100 + /** * scp_ipi_register - register an ipi function * diff --git a/include/linux/rpmsg/mtk_rpmsg.h b/include/linux/rpmsg/mtk_rpmsg.h new file mode 100644 index 00000000000000..8d21cd3d35b012 --- /dev/null +++ b/include/linux/rpmsg/mtk_rpmsg.h @@ -0,0 +1,35 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright 2018 Google LLC. + */ + +#ifndef __LINUX_RPMSG_MTK_RPMSG_H +#define __LINUX_RPMSG_MTK_RPMSG_H + +#include <linux/device.h> +#include <linux/remoteproc.h> + +#if IS_ENABLED(CONFIG_RPMSG_MTK_SCP) + +struct rproc_subdev * +mtk_rpmsg_create_rproc_subdev(struct platform_device *scp_pdev, + struct rproc *scp_rproc); + +void mtk_rpmsg_destroy_rproc_subdev(struct rproc_subdev *subdev); + +#else + +static inline struct rproc_subdev * +mtk_rpmsg_create_rproc_subdev(struct platform_device *scp_pdev, + struct rproc *scp_rproc) +{ + return NULL; +} + +static inline void mtk_rpmsg_destroy_rproc_subdev(struct rproc_subdev *subdev) +{ +} + +#endif + +#endif -- 2.20.1.321.g9e740568ce-goog
