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authorPi-Hsun Shih <pihsun@chromium.org>2019-11-12 19:03:26 +0800
committerBjorn Andersson <bjorn.andersson@linaro.org>2020-01-20 10:29:56 -0800
commit7017996951fde84698ddfe7fd47f92bd9d9eb85d (patch)
treeed20cf19e91e293cae1912bcce6186b34f164f23 /drivers/rpmsg
parent63c13d61eafe4606f1c16c54da40c4eee78e9edf (diff)
downloadlinux-7017996951fde84698ddfe7fd47f92bd9d9eb85d.tar.bz2
rpmsg: add rpmsg support for mt8183 SCP.
Add a simple rpmsg support for mt8183 SCP, that use IPI / IPC directly. Signed-off-by: Pi-Hsun Shih <pihsun@chromium.org> Link: https://lore.kernel.org/r/20191112110330.179649-4-pihsun@chromium.org Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Diffstat (limited to 'drivers/rpmsg')
-rw-r--r--drivers/rpmsg/Kconfig9
-rw-r--r--drivers/rpmsg/Makefile1
-rw-r--r--drivers/rpmsg/mtk_rpmsg.c414
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");