1 /*
2 * Copyright (c) 2024 Felipe Neves.
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #define DT_DRV_COMPAT linaro_ivshmem_mbox
8
9 #include <stdint.h>
10 #include <string.h>
11 #include <zephyr/device.h>
12 #include <zephyr/drivers/mbox.h>
13 #include <zephyr/drivers/virtualization/ivshmem.h>
14 #include <zephyr/logging/log.h>
15 LOG_MODULE_REGISTER(mbox_ivshmem, CONFIG_MBOX_LOG_LEVEL);
16
17 K_THREAD_STACK_DEFINE(ivshmem_ev_loop_stack, CONFIG_MBOX_IVSHMEM_EVENT_LOOP_STACK_SIZE);
18 static struct k_thread ivshmem_ev_loop_thread;
19
20 struct ivshmem_mbox_data {
21 mbox_callback_t cb;
22 void *user_data;
23 };
24
25 struct ivshmem_mbox_config {
26 const struct device *ivshmem_dev;
27 int peer_id;
28 };
29
ivshmem_mbox_event_loop_thread(void * arg,void * p2,void * p3)30 static void ivshmem_mbox_event_loop_thread(void *arg, void *p2, void *p3)
31 {
32 ARG_UNUSED(p2);
33 ARG_UNUSED(p3);
34
35 unsigned int poll_signaled;
36 int ivshmem_vector_rx;
37 struct k_poll_signal sig;
38 struct k_poll_event events[] = {
39 K_POLL_EVENT_INITIALIZER(K_POLL_TYPE_SIGNAL, K_POLL_MODE_NOTIFY_ONLY, &sig),
40 };
41
42 const struct device *dev = (const struct device *)arg;
43 struct ivshmem_mbox_data *dev_data = (struct ivshmem_mbox_data *)dev->data;
44 struct ivshmem_mbox_config *dev_cfg = (struct ivshmem_mbox_config *)dev->config;
45
46 k_poll_signal_init(&sig);
47 int ret = ivshmem_register_handler(dev_cfg->ivshmem_dev, &sig, 0);
48
49 if (ret < 0) {
50 LOG_ERR("registering handlers must be supported: %d\n", ret);
51 k_panic();
52 }
53
54 while (1) {
55 LOG_DBG("%s: waiting interrupt from client...\n", __func__);
56 ret = k_poll(events, ARRAY_SIZE(events), K_FOREVER);
57
58 k_poll_signal_check(&sig, &poll_signaled, &ivshmem_vector_rx);
59 /* get ready for next signal */
60 k_poll_signal_reset(&sig);
61
62 if (dev_data->cb) {
63 dev_data->cb(dev, 0, dev_data->user_data, NULL);
64 }
65 }
66 }
67
ivshmem_mbox_send(const struct device * dev,mbox_channel_id_t channel,const struct mbox_msg * msg)68 static int ivshmem_mbox_send(const struct device *dev, mbox_channel_id_t channel,
69 const struct mbox_msg *msg)
70 {
71 ARG_UNUSED(msg);
72 ARG_UNUSED(channel);
73
74 struct ivshmem_mbox_config *dev_cfg = (struct ivshmem_mbox_config *)dev->config;
75
76 LOG_DBG("sending notification to the peer id 0x%x\n", (int)channel);
77 return ivshmem_int_peer(dev_cfg->ivshmem_dev, (int)channel, 0);
78 }
79
ivshmem_mbox_register_callback(const struct device * dev,mbox_channel_id_t channel,mbox_callback_t cb,void * user_data)80 static int ivshmem_mbox_register_callback(const struct device *dev, mbox_channel_id_t channel,
81 mbox_callback_t cb, void *user_data)
82 {
83 ARG_UNUSED(channel);
84
85 struct ivshmem_mbox_data *dev_data = (struct ivshmem_mbox_data *)dev->data;
86
87 if (!cb) {
88 LOG_ERR("Must provide a callback");
89 return -EINVAL;
90 }
91
92 dev_data->cb = cb;
93 dev_data->user_data = user_data;
94
95 return 0;
96 }
97
98 /* some subsystems needs those functions to be at least implemented,
99 * returning some valid values instead of errors, just provide them.
100 */
101
ivshmem_mbox_mtu_get(const struct device * dev)102 static int ivshmem_mbox_mtu_get(const struct device *dev)
103 {
104 ARG_UNUSED(dev);
105
106 return 0;
107 }
108
ivshmem_mbox_max_channels_get(const struct device * dev)109 static uint32_t ivshmem_mbox_max_channels_get(const struct device *dev)
110 {
111 ARG_UNUSED(dev);
112
113 return UINT16_MAX;
114 }
115
ivshmem_mbox_set_enabled(const struct device * dev,mbox_channel_id_t channel,bool enable)116 static int ivshmem_mbox_set_enabled(const struct device *dev, mbox_channel_id_t channel,
117 bool enable)
118 {
119 ARG_UNUSED(dev);
120 ARG_UNUSED(channel);
121 ARG_UNUSED(enable);
122
123 return 0;
124 }
125
ivshmem_mbox_init(const struct device * dev)126 static int ivshmem_mbox_init(const struct device *dev)
127 {
128 k_thread_create(&ivshmem_ev_loop_thread, ivshmem_ev_loop_stack,
129 CONFIG_MBOX_IVSHMEM_EVENT_LOOP_STACK_SIZE, ivshmem_mbox_event_loop_thread,
130 (void *)dev, NULL, NULL, CONFIG_MBOX_IVSHMEM_EVENT_LOOP_PRIO, 0, K_NO_WAIT);
131
132 return 0;
133 }
134
135 static DEVICE_API(mbox, ivshmem_mbox_driver_api) = {
136 .send = ivshmem_mbox_send,
137 .register_callback = ivshmem_mbox_register_callback,
138 .mtu_get = ivshmem_mbox_mtu_get,
139 .max_channels_get = ivshmem_mbox_max_channels_get,
140 .set_enabled = ivshmem_mbox_set_enabled,
141 };
142
143 #define MBOX_IVSHMEM_INIT(inst) \
144 static const struct ivshmem_mbox_config ivshmem_mbox_cfg_##inst = { \
145 .ivshmem_dev = DEVICE_DT_GET(DT_INST_PHANDLE(inst, ivshmem)), \
146 }; \
147 static struct ivshmem_mbox_data ivshmem_mbox_data_##inst = { \
148 .cb = NULL, \
149 .user_data = NULL, \
150 }; \
151 DEVICE_DT_INST_DEFINE(inst, ivshmem_mbox_init, NULL, &ivshmem_mbox_data_##inst, \
152 &ivshmem_mbox_cfg_##inst, POST_KERNEL, \
153 CONFIG_APPLICATION_INIT_PRIORITY, &ivshmem_mbox_driver_api);
154
155 DT_INST_FOREACH_STATUS_OKAY(MBOX_IVSHMEM_INIT);
156
