/*
* Copyright (C) 2014 Freescale Semiconductor, Inc.
* Freescale IMX Linux-specific MCC implementation.
* MCC library API functions implementation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/string.h>
#include "mcc_config.h"
#if(MCC_OS_USED == MCC_LINUX)
#include <linux/slab.h>
#include <linux/mcc_common.h>
#include <linux/mcc_api.h>
#include <linux/mcc_imx6sx.h>
#include <linux/mcc_linux.h>
#elif (MCC_OS_USED == MCC_MQX)
#include "mcc_api.h"
#include "mcc_common.h"
#endif
#if (MCC_OS_USED == MCC_MQX)
#include "mcc_mqx.h"
extern LWEVENT_STRUCT lwevent_buffer_queued[MCC_MQX_LWEVENT_COMPONENTS_COUNT];
extern LWEVENT_STRUCT lwevent_buffer_freed;
#elif (MCC_OS_USED == MCC_LINUX)
#include <linux/io.h>
#include <linux/sched.h>
#include <linux/imx_sema4.h>
extern wait_queue_head_t buffer_freed_wait_queue, buffer_queued_wait_queue;
extern unsigned int imx_mcc_buffer_queued, imx_mcc_buffer_freed;
extern unsigned long mcc_shm_offset;
#endif
const char * const init_string = MCC_INIT_STRING;
const char * const version_string = MCC_VERSION_STRING;
/*!
* \brief This function initializes the Multi Core Communication subsystem for a given node.
*
* This function should only be called once per node (once in MQX, once per a process in Linux).
* It tries to initialize the bookkeeping structure when the init_string member of this structure
* is not equal to MCC_INIT_STRING, i.e. when no other core had performed the initialization yet.
* Note, that this way of bookkeeping data re-initialization protection is not powerful enough and
* the user application should not rely on this method. Instead, the application should be designed
* to unambiguously assign the core that will perform the MCC initialization.
* Clear the shared memory before the first core is attempting to initialize the MCC
* (in some cases MCC_INIT_STRING remains in the shared memory after the application reset and could
* cause that the bookkeeping data structure is not initialized correctly).
*
* \param[in] node Node number that will be used in endpoints created by this process.
*
* \return MCC_SUCCESS
* \return MCC_ERR_SEMAPHORE (semaphore handling error)
* \return MCC_ERR_INT (interrupt registration error)
*
* \see mcc_destroy
* \see MCC_BOOKEEPING_STRUCT
*/
int mcc_initialize(MCC_NODE node)
{
int i,j = 0;
int return_value = MCC_SUCCESS;
MCC_SIGNAL tmp_signals_received = {(MCC_SIGNAL_TYPE)0, {(MCC_CORE)0, (MCC_NODE)0, (MCC_PORT)0}};
#if (MCC_OS_USED == MCC_MQX)
for(i=0; i<MCC_MQX_LWEVENT_COMPONENTS_COUNT; i++) {
_lwevent_create(&lwevent_buffer_queued[i],0);
}
_lwevent_create(&lwevent_buffer_freed,0);
#endif
/* Initialize synchronization module */
return_value = mcc_init_semaphore(MCC_SHMEM_SEMAPHORE_NUMBER);
if(return_value != MCC_SUCCESS)
return return_value;
/* Register CPU-to-CPU interrupt for inter-core signaling */
return_value = mcc_register_cpu_to_cpu_isr();
if(return_value != MCC_SUCCESS)
return return_value;
/* Initialize the bookeeping structure */
#if (MCC_OS_USED == MCC_LINUX)
bookeeping_data = (MCC_BOOKEEPING_STRUCT *)ioremap_nocache(MCC_BASE_ADDRESS, sizeof(struct mcc_bookeeping_struct));
mcc_shm_offset = (unsigned long)bookeeping_data - (unsigned long)MCC_BASE_ADDRESS;
#elif (MCC_OS_USED == MCC_MQX)
bookeeping_data = (MCC_BOOKEEPING_STRUCT *)MCC_BASE_ADDRESS;
#endif
MCC_DCACHE_INVALIDATE_MLINES(bookeeping_data, sizeof(MCC_BOOKEEPING_STRUCT));
if(strcmp(bookeeping_data->init_string, init_string) != 0) {
/* Zero it all - no guarantee Linux or uboot didnt touch it before it was reserved */
_mem_zero((void*) bookeeping_data, (_mem_size) sizeof(struct mcc_bookeeping_struct));
/* Set init_string in case it has not been set yet by another core */
mcc_memcpy((void*)init_string, bookeeping_data->init_string, (unsigned int)sizeof(bookeeping_data->init_string));
/* Set version_string */
mcc_memcpy((void*)version_string, bookeeping_data->version_string, (unsigned int)sizeof(bookeeping_data->version_string));
/* Initialize the free list */
#if (MCC_OS_USED == MCC_LINUX)
bookeeping_data->free_list.head = (MCC_RECEIVE_BUFFER*)VIRT_TO_MQX(&bookeeping_data->r_buffers[0]);
bookeeping_data->free_list.tail = (MCC_RECEIVE_BUFFER*)VIRT_TO_MQX(&bookeeping_data->r_buffers[MCC_ATTR_NUM_RECEIVE_BUFFERS-1]);
#elif (MCC_OS_USED == MCC_MQX)
bookeeping_data->free_list.head = &bookeeping_data->r_buffers[0];
bookeeping_data->free_list.tail = &bookeeping_data->r_buffers[MCC_ATTR_NUM_RECEIVE_BUFFERS-1];
#endif
/* Initialize receive buffers */
for(i=0; i<MCC_ATTR_NUM_RECEIVE_BUFFERS-1; i++) {
#if (MCC_OS_USED == MCC_LINUX)
bookeeping_data->r_buffers[i].next = (MCC_RECEIVE_BUFFER*)VIRT_TO_MQX(&bookeeping_data->r_buffers[i+1]);
#elif (MCC_OS_USED == MCC_MQX)
bookeeping_data->r_buffers[i].next = &bookeeping_data->r_buffers[i+1];
#endif
}
bookeeping_data->r_buffers[MCC_ATTR_NUM_RECEIVE_BUFFERS-1].next = null;
/* Initialize signal queues */
for(i=0; i<MCC_NUM_CORES; i++) {
for(j=0; j<MCC_MAX_OUTSTANDING_SIGNALS; j++) {
bookeeping_data->signals_received[i][j] = tmp_signals_received;
}
bookeeping_data->signal_queue_head[i] = 0;
bookeeping_data->signal_queue_tail[i] = 0;
}
/* Mark all endpoint ports as free */
for(i=0; i<MCC_ATTR_MAX_RECEIVE_ENDPOINTS; i++) {
bookeeping_data->endpoint_table[i].endpoint.port = MCC_RESERVED_PORT_NUMBER;
}
}
MCC_DCACHE_FLUSH_MLINES(bookeeping_data, sizeof(MCC_BOOKEEPING_STRUCT));
return return_value;
}
EXPORT_SYMBOL(mcc_initialize);
/*!
* \brief This function de-initializes the Multi Core Communication subsystem for a given node.
*
* The function frees all resources of the node. Deletes all endpoints and frees any buffers that may have been queued there.
*
* \param[in] node Node number to be deinitialized.
*
* \return MCC_SUCCESS
* \return MCC_ERR_SEMAPHORE (semaphore handling error)
*
* \see mcc_initialize
*/
int mcc_destroy(MCC_NODE node)
{
int i = 0, return_value;
#if (MCC_OS_USED == MCC_MQX)
for(i=0; i<MCC_MQX_LWEVENT_COMPONENTS_COUNT; i++) {
_lwevent_destroy(&lwevent_buffer_queued[i]);
}
_lwevent_destroy(&lwevent_buffer_freed);
#endif
/* Semaphore-protected section start */
return_value = mcc_get_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
/* All endpoints of the particular node have to be removed from the endpoint table */
MCC_DCACHE_INVALIDATE_MLINES(&bookeeping_data->endpoint_table[0], MCC_ATTR_MAX_RECEIVE_ENDPOINTS * sizeof(MCC_ENDPOINT_MAP_ITEM));
for(i = 0; i < MCC_ATTR_MAX_RECEIVE_ENDPOINTS; i++) {
if (bookeeping_data->endpoint_table[i].endpoint.node == node) {
/* Remove the endpoint from the table */
mcc_remove_endpoint(bookeeping_data->endpoint_table[i].endpoint);
}
}
/* Semaphore-protected section end */
return_value = mcc_release_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
/* Deinitialize synchronization module */
mcc_deinit_semaphore(MCC_SHMEM_SEMAPHORE_NUMBER);
return return_value;
}
EXPORT_SYMBOL(mcc_destroy);
/*!
* \brief This function creates an endpoint.
*
* The function creates an endpoint on the local node with the specified port number.
* The core and node provided in the endpoint must match the caller's core and
* node, and the port argument must match the endpoint port.
*
* \param[out] endpoint Pointer to the endpoint triplet to be created.
* \param[in] port Port number.
*
* \return MCC_SUCCESS
* \return MCC_ERR_NOMEM (maximum number of endpoints exceeded)
* \return MCC_ERR_ENDPOINT (invalid value for port or endpoint already registered)
* \return MCC_ERR_SEMAPHORE (semaphore handling error)
*
* \see mcc_destroy_endpoint
* \see MCC_ENDPOINT
*/
int mcc_create_endpoint(MCC_ENDPOINT *endpoint, MCC_PORT port)
{
int return_value = MCC_SUCCESS;
/* Fill the endpoint structure */
endpoint->core = (MCC_CORE)MCC_CORE_NUMBER;
endpoint->node = (MCC_NODE)MCC_NODE_NUMBER;
endpoint->port = (MCC_PORT)port;
/* Semaphore-protected section start */
return_value = mcc_get_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
/* Add new endpoint data into the book-keeping structure */
return_value = mcc_register_endpoint(*endpoint);
if(return_value != MCC_SUCCESS) {
mcc_release_semaphore();
return return_value;
}
/* Semaphore-protected section end */
return_value = mcc_release_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
return return_value;
}
EXPORT_SYMBOL(mcc_create_endpoint);
/*!
* \brief This function destroys an endpoint.
*
* The function destroys an endpoint on the local node and frees any buffers that may be queued.
*
* \param[in] endpoint Pointer to the endpoint triplet to be deleted.
*
* \return MCC_SUCCESS
* \return MCC_ERR_ENDPOINT (the endpoint doesn't exist)
* \return MCC_ERR_SEMAPHORE (semaphore handling error)
*
* \see mcc_create_endpoint
* \see MCC_ENDPOINT
*/
int mcc_destroy_endpoint(MCC_ENDPOINT *endpoint)
{
int return_value = MCC_SUCCESS;
/* Semaphore-protected section start */
return_value = mcc_get_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
/* Add new endpoint data into the book-keeping structure */
return_value = mcc_remove_endpoint(*endpoint);
if(return_value != MCC_SUCCESS) {
mcc_release_semaphore();
return return_value;
}
/* Semaphore-protected section end */
return_value = mcc_release_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
return return_value;
}
/*!
* \brief This function sends a message to an endpoint.
*
* The message is copied into the MCC buffer and the destination core is signaled.
*
* \param[in] endpoint Pointer to the receiving endpoint to send to.
* \param[in] msg Pointer to the message to be sent.
* \param[in] msg_size Size of the message to be sent in bytes.
* \param[in] timeout_us Timeout, in microseconds, to wait for a free buffer. A value of 0 means don't wait (non-blocking call). A value of 0xffffffff means wait forever (blocking call).
*
* \return MCC_SUCCESS
* \return MCC_ERR_ENDPOINT (the endpoint does not exist)
* \return MCC_ERR_SEMAPHORE (semaphore handling error)
* \return MCC_ERR_INVAL (the msg_size exceeds the size of a data buffer)
* \return MCC_ERR_TIMEOUT (timeout exceeded before a buffer became available)
* \return MCC_ERR_NOMEM (no free buffer available and timeout_us set to 0)
* \return MCC_ERR_SQ_FULL (signal queue is full)
*
* \see mcc_recv_copy
* \see mcc_recv_nocopy
* \see MCC_ENDPOINT
*/
int mcc_send(MCC_ENDPOINT *endpoint, void *msg, MCC_MEM_SIZE msg_size, unsigned int timeout_us)
{
int return_value;
MCC_RECEIVE_LIST *list;
MCC_RECEIVE_BUFFER * buf;
MCC_SIGNAL affiliated_signal;
#if (MCC_OS_USED == MCC_MQX)
int end_time_set_flag = 0;
unsigned int time_us_tmp;
MQX_TICK_STRUCT tick_time;
#elif (MCC_OS_USED == MCC_LINUX)
unsigned long timeout_j; /* jiffies */
#endif
/* Check if the size of the message to be sent does not exceed the size of the mcc buffer */
if(msg_size > sizeof(bookeeping_data->r_buffers[0].data)) {
return MCC_ERR_INVAL;
}
/* Semaphore-protected section start */
return_value = mcc_get_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
/* Dequeue the buffer from the free list */
MCC_DCACHE_INVALIDATE_MLINES((void*)&bookeeping_data->free_list, sizeof(MCC_RECEIVE_LIST*));
buf = mcc_dequeue_buffer(&bookeeping_data->free_list);
while(buf == null) {
mcc_release_semaphore();
/* Non-blocking call */
if(timeout_us == 0) {
return MCC_ERR_NOMEM;
}
/* Blocking calls: CPU-to-CPU ISR sets the event and thus resumes tasks waiting for a free MCC buffer.
* As the interrupt request is send to all cores when a buffer is freed it could happen that several
* tasks from different cores/nodes are waiting for a free buffer and all of them are notified that the buffer
* has been freed. This function has to check (after the wake up) that a buffer is really available and has not been already
* grabbed by another "competitor task" that has been faster. If so, it has to wait again for the next notification. */
/* wait forever */
else if(timeout_us == 0xFFFFFFFF) {
#if (MCC_OS_USED == MCC_MQX)
_lwevent_wait_ticks(&lwevent_buffer_freed, 1, TRUE, 0);
_lwevent_clear(&lwevent_buffer_freed, 1);
#elif (MCC_OS_USED == MCC_LINUX)
timeout_j = usecs_to_jiffies(1000);
wait_event_timeout(buffer_freed_wait_queue, imx_mcc_buffer_freed == 1, timeout_j);
#endif
}
/* timeout_us > 0 */
else {
#if (MCC_OS_USED == MCC_MQX)
if(!end_time_set_flag) {
_time_get_ticks(&tick_time);
_time_add_usec_to_ticks(&tick_time, timeout_us);
end_time_set_flag = 1;
}
return_value = _lwevent_wait_until(&lwevent_buffer_freed, 1, TRUE, &tick_time);
if(return_value == LWEVENT_WAIT_TIMEOUT) {
/* Buffer not dequeued before the timeout */
return MCC_ERR_TIMEOUT;
}
_lwevent_clear(&lwevent_buffer_freed, 1);
#elif (MCC_OS_USED == MCC_LINUX)
timeout_j = usecs_to_jiffies(timeout_us);
wait_event_timeout(buffer_freed_wait_queue, imx_mcc_buffer_freed == 1, timeout_j);
#endif
}
return_value = mcc_get_semaphore();
MCC_DCACHE_INVALIDATE_MLINES((void*)&bookeeping_data->free_list, sizeof(MCC_RECEIVE_LIST*));
buf = mcc_dequeue_buffer(&bookeeping_data->free_list);
}
#if (MCC_OS_USED == MCC_LINUX)
if (imx_mcc_buffer_freed)
imx_mcc_buffer_freed = 0;
#endif
/* Copy the message into the MCC receive buffer */
MCC_DCACHE_INVALIDATE_MLINES((void*)buf, sizeof(MCC_RECEIVE_BUFFER));
mcc_memcpy(msg, (void*)buf->data, (unsigned int)msg_size);
buf->data_len = msg_size;
MCC_DCACHE_FLUSH_MLINES((void*)buf, sizeof(MCC_RECEIVE_BUFFER));
/* Get list of buffers kept by the particular endpoint */
list = mcc_get_endpoint_list(*endpoint);
if(list == null) {
/* The endpoint does not exists (has not been registered so far),
free the buffer and return immediately - error */
/* Enqueue the buffer back into the free list */
MCC_DCACHE_INVALIDATE_MLINES((void*)&bookeeping_data->free_list, sizeof(MCC_RECEIVE_LIST*));
mcc_queue_buffer(&bookeeping_data->free_list, buf);
mcc_release_semaphore();
return MCC_ERR_ENDPOINT;
}
/* Write the signal type into the signal queue of the particular core */
affiliated_signal.type = BUFFER_QUEUED;
affiliated_signal.destination = *endpoint;
return_value = mcc_queue_signal(endpoint->core, affiliated_signal);
if(return_value != MCC_SUCCESS) {
/* Signal queue is full, free the buffer and return immediately - error */
MCC_DCACHE_INVALIDATE_MLINES((void*)&bookeeping_data->free_list, sizeof(MCC_RECEIVE_LIST*));
mcc_queue_buffer(&bookeeping_data->free_list, buf);
mcc_release_semaphore();
return return_value;
}
/* Enqueue the buffer into the endpoint buffer list */
mcc_queue_buffer(list, buf);
/* Semaphore-protected section end */
return_value = mcc_release_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
/* Signal the other core by generating the CPU-to-CPU interrupt */
return_value = mcc_generate_cpu_to_cpu_interrupt();
return return_value;
}
EXPORT_SYMBOL(mcc_send);
/*!
* \brief This function receives a message from the specified endpoint if one is available.
* The data is copied from the receive buffer into the user supplied buffer.
*
* This is the "receive with copy" version of the MCC receive function. This version is simple
* to use but it requires copying data from shared memory into the user space buffer.
* The user has no obligation or burden to manage the shared memory buffers.
*
* \param[in] endpoint Pointer to the receiving endpoint to receive from.
* \param[in] buffer Pointer to the user-app. buffer where data will be copied into.
* \param[in] buffer_size The maximum number of bytes to copy.
* \param[out] recv_size Pointer to an MCC_MEM_SIZE that will contain the number of bytes actually copied into the buffer.
* \param[in] timeout_us Timeout, in microseconds, to wait for a free buffer. A value of 0 means don't wait (non-blocking call). A value of 0xffffffff means wait forever (blocking call).
*
* \return MCC_SUCCESS
* \return MCC_ERR_ENDPOINT (the endpoint does not exist)
* \return MCC_ERR_SEMAPHORE (semaphore handling error)
* \return MCC_ERR_TIMEOUT (timeout exceeded before a new message came)
*
* \see mcc_send
* \see mcc_recv_nocopy
* \see MCC_ENDPOINT
*/
int mcc_recv_copy(MCC_ENDPOINT *endpoint, void *buffer, MCC_MEM_SIZE buffer_size, MCC_MEM_SIZE *recv_size, unsigned int timeout_us)
{
MCC_RECEIVE_LIST *list;
MCC_RECEIVE_BUFFER * buf;
MCC_SIGNAL affiliated_signal;
MCC_ENDPOINT tmp_destination = {(MCC_CORE)0, (MCC_NODE)0, (MCC_PORT)0};
int return_value, i = 0;
#if (MCC_OS_USED == MCC_MQX)
unsigned int time_us_tmp;
unsigned int lwevent_index = endpoint->port / MCC_MQX_LWEVENT_GROUP_SIZE;
unsigned int lwevent_group_index = endpoint->port % MCC_MQX_LWEVENT_GROUP_SIZE;
MQX_TICK_STRUCT tick_time;
#elif (MCC_OS_USED == MCC_LINUX)
unsigned long timeout_j; /* jiffies */
#endif
/* Semaphore-protected section start */
return_value = mcc_get_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
/* Get list of buffers kept by the particular endpoint */
list = mcc_get_endpoint_list(*endpoint);
/* Semaphore-protected section end */
return_value = mcc_release_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
/* The endpoint is not valid */
if(list == null)
return MCC_ERR_ENDPOINT;
if(list->head == (MCC_RECEIVE_BUFFER*)0) {
/* Non-blocking call */
if(timeout_us == 0) {
return MCC_ERR_TIMEOUT;
}
/* Blocking call */
else {
#if (MCC_OS_USED == MCC_MQX)
if(timeout_us == 0xFFFFFFFF) {
_lwevent_wait_ticks(&lwevent_buffer_queued[lwevent_index], 1<<lwevent_group_index, TRUE, 0);
}
/* timeout_us > 0 */
else {
_time_get_ticks(&tick_time);
_time_add_usec_to_ticks(&tick_time, timeout_us);
_lwevent_wait_until(&lwevent_buffer_queued[lwevent_index], 1<<lwevent_group_index, TRUE, &tick_time);
}
#elif (MCC_OS_USED == MCC_LINUX)
if(timeout_us == 0xFFFFFFFF) {
wait_event(buffer_queued_wait_queue, imx_mcc_buffer_queued == 1);
mcc_get_semaphore();
/*
* double check if the list head is null or not,
* if yes, wait again.
*/
while (list->head == null) {
imx_mcc_buffer_queued = 0;
mcc_release_semaphore();
wait_event(buffer_queued_wait_queue, imx_mcc_buffer_queued == 1);
mcc_get_semaphore();
}
}
else {
timeout_j = usecs_to_jiffies(timeout_us);
wait_event_timeout(buffer_queued_wait_queue, imx_mcc_buffer_queued == 1, timeout_j);
mcc_get_semaphore();
}
if (list->head == null) {
pr_err("%s can't get queued buffer.\n", __func__);
}
list->head = (MCC_RECEIVE_BUFFER*)MQX_TO_VIRT(list->head);
mcc_release_semaphore();
#endif
}
}
#if (MCC_OS_USED == MCC_LINUX)
else {
list->head = (MCC_RECEIVE_BUFFER*)MQX_TO_VIRT(list->head);
}
#endif
#if (MCC_OS_USED == MCC_MQX)
/* Clear event bit specified for the particular endpoint in the lwevent_buffer_queued lwevent group */
_lwevent_clear(&lwevent_buffer_queued[lwevent_index], 1<<lwevent_group_index);
#endif
/* Semaphore-protected section start */
return_value = mcc_get_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
MCC_DCACHE_INVALIDATE_MLINES((void*)list, sizeof(MCC_RECEIVE_LIST*));
if(list->head == (MCC_RECEIVE_BUFFER*)0) {
/* Buffer not dequeued before the timeout */
mcc_release_semaphore();
return MCC_ERR_TIMEOUT;
}
/* Copy the message from the MCC receive buffer into the user-app. buffer */
MCC_DCACHE_INVALIDATE_MLINES((void*)&list->head->data_len, sizeof(MCC_MEM_SIZE));
if (list->head->data_len > buffer_size) {
list->head->data_len = buffer_size;
}
*recv_size = (MCC_MEM_SIZE)(list->head->data_len);
MCC_DCACHE_INVALIDATE_MLINES((void*)&list->head->data, list->head->data_len);
mcc_memcpy((void*)list->head->data, buffer, list->head->data_len);
#if (MCC_OS_USED == MCC_LINUX)
if (imx_mcc_buffer_queued)
imx_mcc_buffer_queued = 0;
list->head = (MCC_RECEIVE_BUFFER*)VIRT_TO_MQX(list->head);
#endif
/* Dequeue the buffer from the endpoint list */
buf = mcc_dequeue_buffer(list);
/* Enqueue the buffer into the free list */
MCC_DCACHE_INVALIDATE_MLINES((void*)&bookeeping_data->free_list, sizeof(MCC_RECEIVE_LIST*));
mcc_queue_buffer(&bookeeping_data->free_list, buf);
/* Notify all cores (except of itself) via CPU-to-CPU interrupt that a buffer has been freed */
affiliated_signal.type = BUFFER_FREED;
affiliated_signal.destination = tmp_destination;
for (i=0; i<MCC_NUM_CORES; i++) {
if(i != MCC_CORE_NUMBER) {
mcc_queue_signal(i, affiliated_signal);
}
}
/* Semaphore-protected section end */
return_value = mcc_release_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
mcc_generate_cpu_to_cpu_interrupt();
return return_value;
}
EXPORT_SYMBOL(mcc_recv_copy);
/*!
* \brief This function receives a message from the specified endpoint if one is available. The data is NOT copied into the user-app. buffer.
*
* This is the "zero-copy receive" version of the MCC receive function. No data is copied.
* Only the pointer to the data is returned. This version is fast, but it requires the user to manage
* buffer allocation. Specifically, the user must decide when a buffer is no longer in use and
* make the appropriate API call to free it, see mcc_free_buffer.
*
* \param[in] endpoint Pointer to the receiving endpoint to receive from.
* \param[out] buffer_p Pointer to the MCC buffer of the shared memory where the received data is stored.
* \param[out] recv_size Pointer to an MCC_MEM_SIZE that will contain the number of valid bytes in the buffer.
* \param[in] timeout_us Timeout, in microseconds, to wait for a free buffer. A value of 0 means don't wait (non-blocking call). A value of 0xffffffff means wait forever (blocking call).
*
* \return MCC_SUCCESS
* \return MCC_ERR_ENDPOINT (the endpoint does not exist)
* \return MCC_ERR_SEMAPHORE (semaphore handling error)
* \return MCC_ERR_TIMEOUT (timeout exceeded before a new message came)
*
* \see mcc_send
* \see mcc_recv_copy
* \see MCC_ENDPOINT
*/
int mcc_recv_nocopy(MCC_ENDPOINT *endpoint, void **buffer_p, MCC_MEM_SIZE *recv_size, unsigned int timeout_us)
{
MCC_RECEIVE_LIST *list;
int return_value;
#if (MCC_OS_USED == MCC_MQX)
unsigned int time_us_tmp;
unsigned int lwevent_index = endpoint->port / MCC_MQX_LWEVENT_GROUP_SIZE;
unsigned int lwevent_group_index = endpoint->port % MCC_MQX_LWEVENT_GROUP_SIZE;
MQX_TICK_STRUCT tick_time;
#elif (MCC_OS_USED == MCC_LINUX)
unsigned long timeout_j; /* jiffies */
#endif
/* Semaphore-protected section start */
return_value = mcc_get_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
/* Get list of buffers kept by the particular endpoint */
list = mcc_get_endpoint_list(*endpoint);
/* Semaphore-protected section end */
return_value = mcc_release_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
/* The endpoint is not valid */
if(list == null) {
return MCC_ERR_ENDPOINT;
}
if(list->head == (MCC_RECEIVE_BUFFER*)0) {
/* Non-blocking call */
if(timeout_us == 0) {
return MCC_ERR_TIMEOUT;
}
/* Blocking call */
else {
#if (MCC_OS_USED == MCC_MQX)
if(timeout_us == 0xFFFFFFFF) {
_lwevent_wait_ticks(&lwevent_buffer_queued[lwevent_index], 1<<lwevent_group_index, TRUE, 0);
}
/* timeout_us > 0 */
else {
_time_get_ticks(&tick_time);
_time_add_usec_to_ticks(&tick_time, timeout_us);
_lwevent_wait_until(&lwevent_buffer_queued[lwevent_index], 1<<lwevent_group_index, TRUE, &tick_time);
}
#elif ((MCC_OS_USED == MCC_LINUX))
if(timeout_us == 0xFFFFFFFF) {
wait_event(buffer_queued_wait_queue, imx_mcc_buffer_queued == 1);
mcc_get_semaphore();
/*
* double check if the list head is null or not,
* if yes, wait again.
*/
while (list->head == null) {
imx_mcc_buffer_queued = 0;
mcc_release_semaphore();
wait_event(buffer_queued_wait_queue, imx_mcc_buffer_queued == 1);
mcc_get_semaphore();
}
}
else {
timeout_j = usecs_to_jiffies(timeout_us);
wait_event_timeout(buffer_queued_wait_queue, imx_mcc_buffer_queued == 1, timeout_j);
mcc_get_semaphore();
if (list->head == null)
pr_err("%s can't get queued buffer.\n", __func__);
}
list->head = (MCC_RECEIVE_BUFFER*)MQX_TO_VIRT(list->head);
mcc_release_semaphore();
#endif
}
}
#if (MCC_OS_USED == MCC_LINUX)
else {
list->head = (MCC_RECEIVE_BUFFER*)MQX_TO_VIRT(list->head);
}
#endif
#if (MCC_OS_USED == MCC_MQX)
/* Clear event bit specified for the particular endpoint in the lwevent_buffer_queued lwevent group */
_lwevent_clear(&lwevent_buffer_queued[lwevent_index], 1<<lwevent_group_index);
#endif
/* Semaphore-protected section start */
return_value = mcc_get_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
MCC_DCACHE_INVALIDATE_MLINES((void*)list, sizeof(MCC_RECEIVE_LIST*));
if(list->head == (MCC_RECEIVE_BUFFER*)0) {
/* Buffer not dequeued before the timeout */
mcc_release_semaphore();
return MCC_ERR_TIMEOUT;
}
/* Get the message pointer from the head of the receive buffer list */
MCC_DCACHE_INVALIDATE_MLINES((void*)&list->head->data, list->head->data_len);
*buffer_p = (void*)&list->head->data;
MCC_DCACHE_INVALIDATE_MLINES((void*)&list->head->data_len, sizeof(MCC_MEM_SIZE));
*recv_size = (MCC_MEM_SIZE)(list->head->data_len);
#if (MCC_OS_USED == MCC_LINUX)
list->head = (MCC_RECEIVE_BUFFER*)VIRT_TO_MQX(list->head);
#endif
/* Dequeue the buffer from the endpoint list */
mcc_dequeue_buffer(list);
/* Semaphore-protected section end */
return_value = mcc_release_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
return return_value;
}
/*!
* \brief This function returns the number of buffers currently queued at the endpoint.
*
* The function checks if messages are available on a receive endpoint. While the call only checks the
* availability of messages, it does not dequeue them.
*
* \param[in] endpoint Pointer to the endpoint structure.
* \param[out] num_msgs Pointer to an unsigned int that will contain the number of buffers queued.
*
* \return MCC_SUCCESS
* \return MCC_ERR_ENDPOINT (the endpoint does not exist)
* \return MCC_ERR_SEMAPHORE (semaphore handling error)
*
* \see mcc_recv_copy
* \see mcc_recv_nocopy
* \see MCC_ENDPOINT
*/
int mcc_msgs_available(MCC_ENDPOINT *endpoint, unsigned int *num_msgs)
{
unsigned int count = 0;
MCC_RECEIVE_LIST *list;
MCC_RECEIVE_BUFFER * buf;
int return_value;
/* Semaphore-protected section start */
return_value = mcc_get_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
/* Get list of buffers kept by the particular endpoint */
list = mcc_get_endpoint_list(*endpoint);
if(list == null) {
/* The endpoint does not exists (has not been registered so far), return immediately - error */
mcc_release_semaphore();
return MCC_ERR_ENDPOINT;
}
buf = list->head;
while(buf != (MCC_RECEIVE_BUFFER*)0) {
count++;
MCC_DCACHE_INVALIDATE_MLINES((void*)&buf->next, sizeof(MCC_RECEIVE_BUFFER*));
buf = (MCC_RECEIVE_BUFFER*)buf->next;
}
*num_msgs = count;
/* Semaphore-protected section end */
return_value = mcc_release_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
return return_value;
}
/*!
* \brief This function frees a buffer previously returned by mcc_recv_nocopy().
*
* Once the zero-copy mechanism of receiving data is used, this function
* has to be called to free a buffer and to make it available for the next data
* transfer.
*
* \param[in] buffer Pointer to the buffer to be freed.
*
* \return MCC_SUCCESS
* \return MCC_ERR_SEMAPHORE (semaphore handling error)
*
* \see mcc_recv_nocopy
*/
int mcc_free_buffer(void *buffer)
{
MCC_SIGNAL affiliated_signal;
MCC_ENDPOINT tmp_destination = {(MCC_CORE)0, (MCC_NODE)0, (MCC_PORT)0};
int return_value, i = 0;
/* Semaphore-protected section start */
return_value = mcc_get_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
/* Enqueue the buffer into the free list */
MCC_DCACHE_INVALIDATE_MLINES((void*)&bookeeping_data->free_list, sizeof(MCC_RECEIVE_LIST*));
mcc_queue_buffer(&bookeeping_data->free_list, (MCC_RECEIVE_BUFFER *)((unsigned int)buffer - (unsigned int)(&(((MCC_RECEIVE_BUFFER*)0)->data))));
/* Notify all cores (except of itself) via CPU-to-CPU interrupt that a buffer has been freed */
affiliated_signal.type = BUFFER_FREED;
affiliated_signal.destination = tmp_destination;
for (i=0; i<MCC_NUM_CORES; i++) {
if(i != MCC_CORE_NUMBER) {
mcc_queue_signal(i, affiliated_signal);
}
}
/* Semaphore-protected section end */
return_value = mcc_release_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
mcc_generate_cpu_to_cpu_interrupt();
return return_value;
}
/*!
* \brief This function returns information about the MCC sub system.
*
* The function returns implementation-specific information.
*
* \param[in] node Node number.
* \param[out] info_data Pointer to the MCC_INFO_STRUCT structure to hold returned data.
*
* \return MCC_SUCCESS
* \return MCC_ERR_SEMAPHORE (semaphore handling error)
*
* \see MCC_INFO_STRUCT
*/
int mcc_get_info(MCC_NODE node, MCC_INFO_STRUCT* info_data)
{
int return_value;
/* Semaphore-protected section start */
return_value = mcc_get_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
mcc_memcpy(bookeeping_data->version_string, (void*)info_data->version_string, (unsigned int)sizeof(bookeeping_data->version_string));
/* Semaphore-protected section end */
return_value = mcc_release_semaphore();
if(return_value != MCC_SUCCESS)
return return_value;
return return_value;
}
EXPORT_SYMBOL(mcc_get_info);
