zephyr/drivers/mbox/mbox_ivshmem.c

156 lines
4.5 KiB
C

/*
* Copyright (c) 2024 Felipe Neves.
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT linaro_ivshmem_mbox
#include <stdint.h>
#include <string.h>
#include <zephyr/device.h>
#include <zephyr/drivers/mbox.h>
#include <zephyr/drivers/virtualization/ivshmem.h>
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(mbox_ivshmem, CONFIG_MBOX_LOG_LEVEL);
K_THREAD_STACK_DEFINE(ivshmem_ev_loop_stack, CONFIG_MBOX_IVSHMEM_EVENT_LOOP_STACK_SIZE);
static struct k_thread ivshmem_ev_loop_thread;
struct ivshmem_mbox_data {
mbox_callback_t cb;
void *user_data;
};
struct ivshmem_mbox_config {
const struct device *ivshmem_dev;
int peer_id;
};
static void ivshmem_mbox_event_loop_thread(void *arg, void *p2, void *p3)
{
ARG_UNUSED(p2);
ARG_UNUSED(p3);
unsigned int poll_signaled;
int ivshmem_vector_rx;
struct k_poll_signal sig;
struct k_poll_event events[] = {
K_POLL_EVENT_INITIALIZER(K_POLL_TYPE_SIGNAL, K_POLL_MODE_NOTIFY_ONLY, &sig),
};
const struct device *dev = (const struct device *)arg;
struct ivshmem_mbox_data *dev_data = (struct ivshmem_mbox_data *)dev->data;
struct ivshmem_mbox_config *dev_cfg = (struct ivshmem_mbox_config *)dev->config;
k_poll_signal_init(&sig);
int ret = ivshmem_register_handler(dev_cfg->ivshmem_dev, &sig, 0);
if (ret < 0) {
LOG_ERR("registering handlers must be supported: %d\n", ret);
k_panic();
}
while (1) {
LOG_DBG("%s: waiting interrupt from client...\n", __func__);
ret = k_poll(events, ARRAY_SIZE(events), K_FOREVER);
k_poll_signal_check(&sig, &poll_signaled, &ivshmem_vector_rx);
/* get ready for next signal */
k_poll_signal_reset(&sig);
if (dev_data->cb) {
dev_data->cb(dev, 0, dev_data->user_data, NULL);
}
}
}
static int ivshmem_mbox_send(const struct device *dev, mbox_channel_id_t channel,
const struct mbox_msg *msg)
{
ARG_UNUSED(msg);
ARG_UNUSED(channel);
struct ivshmem_mbox_config *dev_cfg = (struct ivshmem_mbox_config *)dev->config;
LOG_DBG("sending notification to the peer id 0x%x\n", (int)channel);
return ivshmem_int_peer(dev_cfg->ivshmem_dev, (int)channel, 0);
}
static int ivshmem_mbox_register_callback(const struct device *dev, mbox_channel_id_t channel,
mbox_callback_t cb, void *user_data)
{
ARG_UNUSED(channel);
struct ivshmem_mbox_data *dev_data = (struct ivshmem_mbox_data *)dev->data;
if (!cb) {
LOG_ERR("Must provide a callback");
return -EINVAL;
}
dev_data->cb = cb;
dev_data->user_data = user_data;
return 0;
}
/* some subsystems needs those functions to be at least implemented,
* returning some valid values instead of errors, just provide them.
*/
static int ivshmem_mbox_mtu_get(const struct device *dev)
{
ARG_UNUSED(dev);
return 0;
}
static uint32_t ivshmem_mbox_max_channels_get(const struct device *dev)
{
ARG_UNUSED(dev);
return UINT16_MAX;
}
static int ivshmem_mbox_set_enabled(const struct device *dev, mbox_channel_id_t channel,
bool enable)
{
ARG_UNUSED(dev);
ARG_UNUSED(channel);
ARG_UNUSED(enable);
return 0;
}
static int ivshmem_mbox_init(const struct device *dev)
{
k_thread_create(&ivshmem_ev_loop_thread, ivshmem_ev_loop_stack,
CONFIG_MBOX_IVSHMEM_EVENT_LOOP_STACK_SIZE, ivshmem_mbox_event_loop_thread,
(void *)dev, NULL, NULL, CONFIG_MBOX_IVSHMEM_EVENT_LOOP_PRIO, 0, K_NO_WAIT);
return 0;
}
static const struct mbox_driver_api ivshmem_mbox_driver_api = {
.send = ivshmem_mbox_send,
.register_callback = ivshmem_mbox_register_callback,
.mtu_get = ivshmem_mbox_mtu_get,
.max_channels_get = ivshmem_mbox_max_channels_get,
.set_enabled = ivshmem_mbox_set_enabled,
};
#define MBOX_IVSHMEM_INIT(inst) \
static const struct ivshmem_mbox_config ivshmem_mbox_cfg_##inst = { \
.ivshmem_dev = DEVICE_DT_GET(DT_INST_PHANDLE(inst, ivshmem)), \
}; \
static struct ivshmem_mbox_data ivshmem_mbox_data_##inst = { \
.cb = NULL, \
.user_data = NULL, \
}; \
DEVICE_DT_INST_DEFINE(inst, ivshmem_mbox_init, NULL, &ivshmem_mbox_data_##inst, \
&ivshmem_mbox_cfg_##inst, POST_KERNEL, \
CONFIG_APPLICATION_INIT_PRIORITY, &ivshmem_mbox_driver_api);
DT_INST_FOREACH_STATUS_OKAY(MBOX_IVSHMEM_INIT);