sdram.h

00001 /*
00002  *  Copyright 2013 Embedded Artists AB
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 
00017 #ifndef __SDRAM_H
00018 #define __SDRAM_H
00019 
00020 #include "stdint.h"
00021 
00022 /*
00023  * These timing parameters are based on the EMC clock
00024  * there is no way of ensuring what the EMC clock frequency is
00025  * without severely bloating the code
00026  * ENSURE THAT THE EMC clock is one of these values
00027  */
00028 #define SDRAM_SPEED_48 0
00029 #define SDRAM_SPEED_50 1
00030 #define SDRAM_SPEED_60 2
00031 #define SDRAM_SPEED_72 3
00032 #define SDRAM_SPEED_80 4
00033 
00034 #define SDRAM_SPEED SDRAM_SPEED_60
00035 
00036 #define SDRAM_CONFIG_32BIT
00037 #define SDRAM_SIZE               0x2000000
00038 
00039 #define SDRAM_BASE               0xA0000000 /*CS0*/
00040 
00041 /* Initializes the SDRAM.
00042  *
00043  * The entire SDRAM will be made available to malloc per default.
00044  *
00045  * Note that this functions is called internally if malloc requests
00046  * memory from SDRAM and that hasn't been disabled with a call to
00047  * sdram_disableMallocSdram().
00048  *
00049  * @returns 0 on success, 1 on failure
00050  */
00051 uint32_t sdram_init();
00052 
00053 /* Prevents malloc from using SDRAM.
00054  *
00055  * This function must be called before the first allocation that 
00056  * would have been in SDRAM. If a big allocation has already been
00057  * made then this call will do nothing as the SDRAM will have been
00058  * initialized and all SDRAM given to malloc.
00059  */
00060 void sdram_disableMallocSdram();
00061 
00062 #endif /* end __SDRAM_H */
00063 /****************************************************************************
00064 **                            End Of File
00065 *****************************************************************************/
00066 
00067