// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (c) 2014-2017, The Linux Foundation. All rights reserved. * Copyright (c) 2017, Linaro Ltd. */ #include <linux/completion.h> #include <linux/module.h> #include <linux/notifier.h> #include <linux/rpmsg.h> #include <linux/remoteproc/qcom_rproc.h> /** * struct do_cleanup_msg - The data structure for an SSR do_cleanup message * version: The G-Link SSR protocol version * command: The G-Link SSR command - do_cleanup * seq_num: Sequence number * name_len: Length of the name of the subsystem being restarted * name: G-Link edge name of the subsystem being restarted */ struct do_cleanup_msg { __le32 version; __le32 command; __le32 seq_num; __le32 name_len; char name[32]; }; /** * struct cleanup_done_msg - The data structure for an SSR cleanup_done message * version: The G-Link SSR protocol version * response: The G-Link SSR response to a do_cleanup command, cleanup_done * seq_num: Sequence number */ struct cleanup_done_msg { __le32 version; __le32 response; __le32 seq_num; }; /** * G-Link SSR protocol commands */ #define GLINK_SSR_DO_CLEANUP 0 #define GLINK_SSR_CLEANUP_DONE 1 struct glink_ssr { struct device *dev; struct rpmsg_endpoint *ept; struct notifier_block nb; u32 seq_num; struct completion completion; }; static int qcom_glink_ssr_callback(struct rpmsg_device *rpdev, void *data, int len, void *priv, u32 addr) { struct cleanup_done_msg *msg = data; struct glink_ssr *ssr = dev_get_drvdata(&rpdev->dev); if (len < sizeof(*msg)) { dev_err(ssr->dev, "message too short\n"); return -EINVAL; } if (le32_to_cpu(msg->version) != 0) return -EINVAL; if (le32_to_cpu(msg->response) != GLINK_SSR_CLEANUP_DONE) return 0; if (le32_to_cpu(msg->seq_num) != ssr->seq_num) { dev_err(ssr->dev, "invalid sequence number of response\n"); return -EINVAL; } complete(&ssr->completion); return 0; } static int qcom_glink_ssr_notify(struct notifier_block *nb, unsigned long event, void *data) { struct glink_ssr *ssr = container_of(nb, struct glink_ssr, nb); struct do_cleanup_msg msg; char *ssr_name = data; int ret; ssr->seq_num++; reinit_completion(&ssr->completion); memset(&msg, 0, sizeof(msg)); msg.command = cpu_to_le32(GLINK_SSR_DO_CLEANUP); msg.seq_num = cpu_to_le32(ssr->seq_num); msg.name_len = cpu_to_le32(strlen(ssr_name)); strlcpy(msg.name, ssr_name, sizeof(msg.name)); ret = rpmsg_send(ssr->ept, &msg, sizeof(msg)); if (ret < 0) dev_err(ssr->dev, "failed to send cleanup message\n"); ret = wait_for_completion_timeout(&ssr->completion, HZ); if (!ret) dev_err(ssr->dev, "timeout waiting for cleanup done message\n"); return NOTIFY_DONE; } static int qcom_glink_ssr_probe(struct rpmsg_device *rpdev) { struct glink_ssr *ssr; ssr = devm_kzalloc(&rpdev->dev, sizeof(*ssr), GFP_KERNEL); if (!ssr) return -ENOMEM; init_completion(&ssr->completion); ssr->dev = &rpdev->dev; ssr->ept = rpdev->ept; ssr->nb.notifier_call = qcom_glink_ssr_notify; dev_set_drvdata(&rpdev->dev, ssr); return qcom_register_ssr_notifier(&ssr->nb); } static void qcom_glink_ssr_remove(struct rpmsg_device *rpdev) { struct glink_ssr *ssr = dev_get_drvdata(&rpdev->dev); qcom_unregister_ssr_notifier(&ssr->nb); } static const struct rpmsg_device_id qcom_glink_ssr_match[] = { { "glink_ssr" }, {} }; static struct rpmsg_driver qcom_glink_ssr_driver = { .probe = qcom_glink_ssr_probe, .remove = qcom_glink_ssr_remove, .callback = qcom_glink_ssr_callback, .id_table = qcom_glink_ssr_match, .drv = { .name = "qcom_glink_ssr", }, }; module_rpmsg_driver(qcom_glink_ssr_driver); MODULE_ALIAS("rpmsg:glink_ssr"); MODULE_DESCRIPTION("Qualcomm GLINK SSR notifier"); MODULE_LICENSE("GPL v2");