scmi_shmem_read_msg_payload
ret = scmi_shmem_read_msg_payload(sc->a2p_dev,
int scmi_shmem_read_msg_payload(device_t dev, uint8_t *buf, uint32_t buf_len, uint32_t rx_len);
ret = scmi_shmem_read_msg_payload(sc->a2p_dev,