True FFS内核编程
1、格式化FLASH
即使FLASH没有和块设备驱动绑定，也可对其进行格式化。
tffsDevFormat (int tffsDriveNo, int formatArg);
typedef struct
{
tffsFormatParams formatParams;
unsigned formatFlags;
} tffsDevFormatParams;
2、创建Boot Image区域
2.1 创建Boot Image区域
创建Boot Image区域，通过在格式化flash，使TFFS段从某个偏移的位置开始。
tffsFormatParams
typedef struct {
long int bootImageLen; //保留给Boot Image空间大小
unsigned percentUse;
unsigned noOfSpareUnits;
unsigned long vmAddressingLimit;
int (*progressCallback)(int totalUnitsToFormat, int totalUnitsFormattedSoFar);
char * volumeLabel;
unsigned noOfFATcopies;
unsigned embeddedCISlength;
char * embeddedCIS;
} tffsFormatParams;
STATUS sysTffsFormat (void)
{
STATUS status;
tffsDevFormatParams params =
{
#define HALF_FORMAT /* lower 0.5MB for bootimage, upper 1.5MB for TFFS */
#ifdef HALF_FORMAT
{0x80000l, 99, 1, 0x10000l, NULL, {0,0,0,0}, NULL, 2, 0, NULL},
#else
{0x000000l, 99, 1, 0x10000l, NULL, {0,0,0,0}, NULL, 2, 0, NULL},
#endif /* HALF_FORMAT */
FTL_FORMAT_IF_NEEDED
};
/* we assume that the drive number 0 is RFA */
status = tffsDevFormat (0, (int)¶ms);
return (status);
}
2.2 写Boot Image到FLASH
采用函数tffsBootImagePut()实现，该函数依赖tffsRawio()，所以不能在TFFS卷装载以后使用。
TffsBootImagePut()能直接操作FLASH的任何区域。
函数定义：
STATUS tffsBootImagePut
(
int driveNo, /* TFFS drive number */
int offset, /* offset in the flash chip/card */
char * filename /* binary format of the bootimage */
)
3 mounting the driver
函数usrTffsConfig()把dosFile文件系统加载到TFFS Flash驱动上。
STATUS usrTffsConfig
(
int drive, /* drive number of TFFS */
int removable, /* 0 for nonremovable flash media */
char * fileName /* mount point */
)
STATUS usrTffsConfig ( int drive, int removable, char * fileName )
{
int dosFsCacheSizeDefault = 128 * 1024 ;
CBIO_DEV_ID pCbio;
BLK_DEV * pBlkDev;
char devName [BOOT_FILE_LEN];
if ((UINT)drive >= noOfDrives) {
printErr ("drive is out of range (0-%d)./n", noOfDrives - 1);
return (ERROR);
}
/* create a block device spanning entire disk (non-distructive!) */
if ((pBlkDev = tffsDevCreate (drive, removable)) == NULL) {
printErr ("tffsDevCreate failed./n");
return (ERROR);
}
/* split off boot device from boot file */
devSplit (fileName, devName);
/* initialize the block device as a dosFs device named */
/* Create e.g. 128 Kbytes disk cache */
if ( (pCbio = dcacheDevCreate( (CBIO_DEV_ID) pBlkDev, NULL,
dosFsCacheSizeDefault, devName)) == NULL )
return (ERROR);
if (dosFsDevCreate (devName, pCbio, 0, NONE) != OK)
return (ERROR);
return (OK);
}
4 TFFS SHELL命令
格式化flash，但保留Boot Image区域。
-> sysTffsFormat
加载RFA medium做为驱动0
-> usrTffsConfig 0,0,"/RFA/"
转自：http://m.blog.csdn.net/blog/da895/6033647