emac_stack_mem.h

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2016 ARM Limited
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 #ifndef MBED_EMAC_STACK_MEM_H
00017 #define MBED_EMAC_STACK_MEM_H
00018 
00019 #if DEVICE_EMAC
00020 
00021 #include <stdint.h>
00022 
00023 /**
00024  * Stack memory module
00025  *
00026  * This interface provides abstraction for memory modules used in different IP stacks (often to accommodate zero copy).
00027  * Emac interface may be required to accept output packets and provide received data using this stack specific API.
00028  * This header should be implemented for each IP stack, so that we keep emacs module independent.
00029  */
00030 typedef void emac_stack_mem_t;
00031 typedef void emac_stack_mem_chain_t;
00032 typedef void emac_stack_t;
00033 
00034 /**
00035  * Allocates stack memory
00036  *
00037  * @param  stack Emac stack context
00038  * @param  size  Size of memory to allocate
00039  * @param  align Memory alignment requirements
00040  * @return       Allocated memory struct, or NULL in case of error
00041  */
00042 emac_stack_mem_t *emac_stack_mem_alloc(emac_stack_t* stack, uint32_t size, uint32_t align);
00043 
00044 /**
00045  * Free memory allocated using @a stack_mem_alloc
00046  *
00047  * @param  stack Emac stack context
00048  * @param mem Memory to be freed
00049  */
00050 void emac_stack_mem_free(emac_stack_t* stack, emac_stack_mem_t *mem);
00051 
00052 /**
00053  * Return pointer to the payload
00054  *
00055  * @param  stack Emac stack context
00056  * @param  mem Memory structure
00057  * @return     Pointer to the payload
00058  */
00059 void *emac_stack_mem_ptr(emac_stack_t* stack, emac_stack_mem_t *mem);
00060 
00061 /**
00062  * Return actual payload size
00063  *
00064  * @param  stack Emac stack context
00065  * @param  mem Memory structure
00066  * @return     Size in bytes
00067  */
00068 uint32_t emac_stack_mem_len(emac_stack_t* stack, emac_stack_mem_t *mem);
00069 
00070 /**
00071  * Sets the actual payload size (the allocated payload size will not change)
00072  *
00073  * @param stack Emac stack context
00074  * @param mem Memory structure
00075  * @param len Actual payload size
00076  */
00077 void emac_stack_mem_set_len(emac_stack_t* stack, emac_stack_mem_t *mem, uint32_t len);
00078 
00079 /**
00080  * Returns first memory structure from the list and move the head to point to the next node
00081  *
00082  * @param  stack Emac stack context
00083  * @param  list Pointer to the list
00084  * @return      First memory structure from the list
00085  */
00086 emac_stack_mem_t *emac_stack_mem_chain_dequeue(emac_stack_t* stack, emac_stack_mem_chain_t **chain);
00087 
00088 /**
00089  * Return total length of the memory chain
00090  *
00091  * @param  stack Emac stack context
00092  * @param  chain Memory chain
00093  * @return       Chain length
00094  */
00095 uint32_t emac_stack_mem_chain_len(emac_stack_t* stack, emac_stack_mem_chain_t *chain);
00096 
00097 /**
00098  * Increases the reference counter for the memory
00099  *
00100  * @param  stack Emac stack context
00101  * @param  mem   Memory structure
00102  */
00103 void emac_stack_mem_ref(emac_stack_t* stack, emac_stack_mem_t *mem);
00104 
00105 #endif /* DEVICE_EMAC */
00106 
00107 #endif /* EMAC_MBED_STACK_MEM_h */