translat.c

PDA上的CF CARD 文件系统的建立程式

/*************************************************************
File Name: TRANSLAT.C                                        *
**************************************************************
Programmer: Huang Giun-Haur
Last Modified Date: 1999/2/1
Compiler : Gnu Cross-compiler
Platform : X86 protection mode
Usage :
	unsigned long	FAT_cluster_to_logical_sector(unsigned short cluster)

	void		FAT_logical_sector_to_chs(unsigned long sectorNO, 
					       struct FAT_C_H_S *p )
*************************************************************/

#include <sys/constant.h>

// added by chilong 01/30/2002
#include "../../FileSys/include/FileSys.h"

#include "../include/fat1x.h"

#ifdef FAT_USE_PCMCIA
  /**** added by chilong ****/
  //#include "../pcm/cf_typedef.h"
  /**** added by chilong ****/
  #include "../include/ata_pcc.h"
#else
  #include "../include/ata_pcc.h"
#endif


#ifdef FAT_ID



/* init.c */
extern unsigned short	FATSecPerCluster[];
extern unsigned long	FATDataBegin[];

extern int		FATIsLBA;
extern struct FAT_C_H_S	FATDiskInfo;

/*************************************************************
Function: FAT_cluster_to_logical_sector
Descirption:
	Transfer the cluster number to the beginning of
	its logical sector number; logical sector number
	start at 0, which represents the boot sector
ThreadSafe:
**************************************************************/
unsigned long FAT_cluster_to_logical_sector(short drive, unsigned short cluster)
{
  return (unsigned long)(FATDataBegin[drive] + ((unsigned long)cluster
                         - NO_OF_RESERVED_CLUSTER) * FATSecPerCluster[drive]);
}



/*************************************************************
Function : LOGICAL_TO_CHS
Descirption :
	Transfer logical sector to CHS.
	
CHS:	Logical sector 0 (boot sector) is CHS(0,0,1), so we
	must add it to CHS.
LBA:	Logical sector 0 is the MBR of the drive.
        A LBA address is stored as follows:
        |31--24|23--16|15--08|07--00|
           H      CH     CL     S
**************************************************************/
void FAT_logical_sector_to_chs(unsigned long sectorNO, struct FAT_C_H_S *p)
{
#ifdef FAT_USE_PCMCIA
  unsigned long h1;

  if (FATIsLBA == FALSE)	/* CHS */
  {
	p->Sector   = (unsigned char)(sectorNO % FATDiskInfo.Sector) + 1;
//	h1	    = (sectorNO / FATDiskInfo.Sector) + 1;
	h1	    = sectorNO / FATDiskInfo.Sector;
	p->Head     = (unsigned char)((h1) % FATDiskInfo.Head);
	p->Cylinder = (unsigned short)(h1 / FATDiskInfo.Head);
	p->CylHigh  = (unsigned char)(p->Cylinder >> 8);
	p->CylLow   = (unsigned char)(p->Cylinder & 0x00FF);
  }
  else			/* LBA */
  {
	p->Sector = (unsigned char)(sectorNO & 0x000000ff);
	h1 = sectorNO >> 8;
	p->CylLow = (unsigned char)(h1 & 0x000000ff);
	h1 = h1 >> 8;
	p->CylHigh = (unsigned char)(h1 & 0x000000ff);
	h1 = h1 >> 8;
	p->Head = (unsigned char)(h1 & 0x000000ff);
  }
#endif
}



#endif	// #ifdef FAT_ID