cmd/fdc.c - github/trini/u-boot - Gitiles

 /*
  * (C) Copyright 2001
  * Denis Peter, MPL AG, d.peter@mpl.ch.
  *
  * SPDX-License-Identifier:	GPL-2.0+
  */
 /*
  * Floppy Disk support
  */

 #include <common.h>
 #include <config.h>
 #include <command.h>
 #include <image.h>


 #undef	FDC_DEBUG

 #ifdef	FDC_DEBUG
 #define	PRINTF(fmt,args...)	printf (fmt ,##args)
 #else
 #define PRINTF(fmt,args...)
 #endif

 /*#if defined(CONFIG_CMD_DATE) */
 /*#include <rtc.h> */
 /*#endif */

 typedef struct {
 	int		flags;		/* connected drives ect */
 	unsigned long	blnr;		/* Logical block nr */
 	uchar		drive;		/* drive no */
 	uchar		cmdlen;		/* cmd length */
 	uchar		cmd[16];	/* cmd desc */
 	uchar		dma;		/* if > 0 dma enabled */
 	uchar		result[11];	/* status information */
 	uchar		resultlen;	/* lenght of result */
 } FDC_COMMAND_STRUCT;

 /* flags: only the lower 8bit used:
  * bit 0 if set drive 0 is present
  * bit 1 if set drive 1 is present
  * bit 2 if set drive 2 is present
  * bit 3 if set drive 3 is present
  * bit 4 if set disk in drive 0 is inserted
  * bit 5 if set disk in drive 1 is inserted
  * bit 6 if set disk in drive 2 is inserted
  * bit 7 if set disk in drive 4 is inserted
  */

 /* cmd indexes */
 #define COMMAND			0
 #define DRIVE			1
 #define CONFIG0			1
 #define SPEC_HUTSRT		1
 #define TRACK			2
 #define CONFIG1			2
 #define SPEC_HLT		2
 #define HEAD			3
 #define CONFIG2			3
 #define SECTOR			4
 #define SECTOR_SIZE		5
 #define LAST_TRACK		6
 #define GAP			7
 #define DTL			8
 /* result indexes */
 #define STATUS_0		0
 #define STATUS_PCN		1
 #define STATUS_1		1
 #define STATUS_2		2
 #define STATUS_TRACK		3
 #define STATUS_HEAD		4
 #define STATUS_SECT		5
 #define STATUS_SECT_SIZE	6


 /* Register addresses */
 #define FDC_BASE	0x3F0
 #define FDC_SRA		FDC_BASE + 0	/* Status Register A */
 #define FDC_SRB		FDC_BASE + 1	/* Status Register B */
 #define FDC_DOR		FDC_BASE + 2	/* Digital Output Register */
 #define FDC_TDR		FDC_BASE + 3	/* Tape Drive Register */
 #define FDC_DSR		FDC_BASE + 4	/* Data rate Register */
 #define FDC_MSR		FDC_BASE + 4	/* Main Status Register */
 #define FDC_FIFO	FDC_BASE + 5	/* FIFO */
 #define FDC_DIR		FDC_BASE + 6	/* Digital Input Register */
 #define FDC_CCR		FDC_BASE + 7	/* Configuration Control */
 /* Commands */
 #define FDC_CMD_SENSE_INT	0x08
 #define FDC_CMD_CONFIGURE	0x13
 #define FDC_CMD_SPECIFY		0x03
 #define FDC_CMD_RECALIBRATE	0x07
 #define FDC_CMD_READ		0x06
 #define FDC_CMD_READ_TRACK	0x02
 #define FDC_CMD_READ_ID		0x0A
 #define FDC_CMD_DUMP_REG	0x0E
 #define FDC_CMD_SEEK		0x0F

 #define FDC_CMD_SENSE_INT_LEN	0x01
 #define FDC_CMD_CONFIGURE_LEN	0x04
 #define FDC_CMD_SPECIFY_LEN	0x03
 #define FDC_CMD_RECALIBRATE_LEN	0x02
 #define FDC_CMD_READ_LEN	0x09
 #define FDC_CMD_READ_TRACK_LEN	0x09
 #define FDC_CMD_READ_ID_LEN	0x02
 #define FDC_CMD_DUMP_REG_LEN	0x01
 #define FDC_CMD_SEEK_LEN	0x03

 #define FDC_FIFO_THR		0x0C
 #define FDC_FIFO_DIS		0x00
 #define FDC_IMPLIED_SEEK	0x01
 #define FDC_POLL_DIS		0x00
 #define FDC_PRE_TRK		0x00
 #define FDC_CONFIGURE		FDC_FIFO_THR | (FDC_POLL_DIS<<4) | (FDC_FIFO_DIS<<5) | (FDC_IMPLIED_SEEK << 6)
 #define FDC_MFM_MODE		0x01 /* MFM enable */
 #define FDC_SKIP_MODE		0x00 /* skip enable */

 #define FDC_TIME_OUT 100000 /* time out */
 #define	FDC_RW_RETRIES		3 /* read write retries */
 #define FDC_CAL_RETRIES		3 /* calibration and seek retries */


 /* Disk structure */
 typedef struct  {
 	unsigned int size;	/* nr of sectors total */
 	unsigned int sect;	/* sectors per track */
 	unsigned int head;	/* nr of heads */
 	unsigned int track;	/* nr of tracks */
 	unsigned int stretch;	/* !=0 means double track steps */
 	unsigned char	gap;	/* gap1 size */
 	unsigned char	rate;	/* data rate. |= 0x40 for perpendicular */
 	unsigned char	spec1;	/* stepping rate, head unload time */
 	unsigned char	fmt_gap;/* gap2 size */
 	unsigned char hlt;	/* head load time */
 	unsigned char sect_code;/* Sector Size code */
 	const char	* name;	/* used only for predefined formats */
 } FD_GEO_STRUCT;


 /* supported Floppy types (currently only one) */
 const static FD_GEO_STRUCT floppy_type[2] = {
 	{ 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,16,2,"H1440" },	/*  7 1.44MB 3.5"   */
 	{    0, 0,0, 0,0,0x00,0x00,0x00,0x00, 0,0,NULL    },	/*  end of table    */
 };

 static FDC_COMMAND_STRUCT cmd; /* global command struct */

 /* If the boot drive number is undefined, we assume it's drive 0             */
 #ifndef CONFIG_SYS_FDC_DRIVE_NUMBER
 #define CONFIG_SYS_FDC_DRIVE_NUMBER 0
 #endif

 /* Hardware access */
 #ifndef CONFIG_SYS_ISA_IO_STRIDE
 #define CONFIG_SYS_ISA_IO_STRIDE 1
 #endif

 #ifndef CONFIG_SYS_ISA_IO_OFFSET
 #define CONFIG_SYS_ISA_IO_OFFSET 0
 #endif

 /* Supporting Functions */
 /* reads a Register of the FDC */
 unsigned char read_fdc_reg(unsigned int addr)
 {
 	volatile unsigned char *val =
 		(volatile unsigned char *)(CONFIG_SYS_ISA_IO_BASE_ADDRESS +
 					   (addr * CONFIG_SYS_ISA_IO_STRIDE) +
 					   CONFIG_SYS_ISA_IO_OFFSET);

 	return val [0];
 }

 /* writes a Register of the FDC */
 void write_fdc_reg(unsigned int addr, unsigned char val)
 {
 	volatile unsigned char *tmp =
 		(volatile unsigned char *)(CONFIG_SYS_ISA_IO_BASE_ADDRESS +
 					   (addr * CONFIG_SYS_ISA_IO_STRIDE) +
 					   CONFIG_SYS_ISA_IO_OFFSET);
 	tmp[0]=val;
 }

 /* waits for an interrupt (polling) */
 int wait_for_fdc_int(void)
 {
 	unsigned long timeout;
 	timeout = FDC_TIME_OUT;
 	while((read_fdc_reg(FDC_SRA)&0x80)==0) {
 		timeout--;
 		udelay(10);
 		if(timeout==0) /* timeout occured */
 			return false;
 	}
 	return true;
 }

 /* reads a byte from the FIFO of the FDC and checks direction and RQM bit
    of the MSR. returns -1 if timeout, or byte if ok */
 int read_fdc_byte(void)
 {
 	unsigned long timeout;
 	timeout = FDC_TIME_OUT;
 	while((read_fdc_reg(FDC_MSR)&0xC0)!=0xC0) {
 		/* direction out and ready */
 		udelay(10);
 		timeout--;
 		if(timeout==0) /* timeout occured */
 			return -1;
 	}
 	return read_fdc_reg(FDC_FIFO);
 }

 /* if the direction of the FIFO is wrong, this routine is used to
    empty the FIFO. Should _not_ be used */
 int fdc_need_more_output(void)
 {
 	unsigned char c;
 	while((read_fdc_reg(FDC_MSR)&0xC0)==0xC0)	{
 			c=(unsigned char)read_fdc_byte();
 			printf("Error: more output: %x\n",c);
 	}
 	return true;
 }


 /* writes a byte to the FIFO of the FDC and checks direction and RQM bit
    of the MSR */
 int write_fdc_byte(unsigned char val)
 {
 	unsigned long timeout;
 	timeout = FDC_TIME_OUT;
 	while((read_fdc_reg(FDC_MSR)&0xC0)!=0x80) {
 		/* direction in and ready for byte */
 		timeout--;
 		udelay(10);
 		fdc_need_more_output();
 		if(timeout==0) /* timeout occured */
 			return false;
 	}
 	write_fdc_reg(FDC_FIFO,val);
 	return true;
 }

 /* sets up all FDC commands and issues it to the FDC. If
    the command causes direct results (no Execution Phase)
    the result is be read as well. */

 int fdc_issue_cmd(FDC_COMMAND_STRUCT *pCMD,FD_GEO_STRUCT *pFG)
 {
 	int i;
 	unsigned long head,track,sect,timeout;
 	track = pCMD->blnr / (pFG->sect * pFG->head); /* track nr */
 	sect =  pCMD->blnr % (pFG->sect * pFG->head); /* remaining blocks */
 	head = sect / pFG->sect; /* head nr */
 	sect =  sect % pFG->sect; /* remaining blocks */
 	sect++; /* sectors are 1 based */
 	PRINTF("Cmd 0x%02x Track %ld, Head %ld, Sector %ld, Drive %d (blnr %ld)\n",
 		pCMD->cmd[0],track,head,sect,pCMD->drive,pCMD->blnr);

 	if(head|=0) { /* max heads = 2 */
 		pCMD->cmd[DRIVE]=pCMD->drive | 0x04; /* head 1 */
 		pCMD->cmd[HEAD]=(unsigned char) head; /* head register */
 	}
 	else {
 		pCMD->cmd[DRIVE]=pCMD->drive; /* head 0 */
 		pCMD->cmd[HEAD]=(unsigned char) head; /* head register */
 	}
 	pCMD->cmd[TRACK]=(unsigned char) track; /* track */
 	switch (pCMD->cmd[COMMAND]) {
 		case FDC_CMD_READ:
 			pCMD->cmd[SECTOR]=(unsigned char) sect; /* sector */
 			pCMD->cmd[SECTOR_SIZE]=pFG->sect_code; /* sector size code */
 			pCMD->cmd[LAST_TRACK]=pFG->sect; /* End of track */
 			pCMD->cmd[GAP]=pFG->gap; /* gap */
 			pCMD->cmd[DTL]=0xFF; /* DTL */
 			pCMD->cmdlen=FDC_CMD_READ_LEN;
 			pCMD->cmd[COMMAND]|=(FDC_MFM_MODE<<6); /* set MFM bit */
 			pCMD->cmd[COMMAND]|=(FDC_SKIP_MODE<<5); /* set Skip bit */
 			pCMD->resultlen=0;  /* result only after execution */
 			break;
 		case FDC_CMD_SEEK:
 			pCMD->cmdlen=FDC_CMD_SEEK_LEN;
 			pCMD->resultlen=0;  /* no result */
 			break;
 		case FDC_CMD_CONFIGURE:
 			pCMD->cmd[CONFIG0]=0;
 			pCMD->cmd[CONFIG1]=FDC_CONFIGURE; /* FIFO Threshold, Poll, Enable FIFO */
 			pCMD->cmd[CONFIG2]=FDC_PRE_TRK;	/* Precompensation Track */
 			pCMD->cmdlen=FDC_CMD_CONFIGURE_LEN;
 			pCMD->resultlen=0;  /* no result */
 			break;
 		case FDC_CMD_SPECIFY:
 			pCMD->cmd[SPEC_HUTSRT]=pFG->spec1;
 			pCMD->cmd[SPEC_HLT]=(pFG->hlt)<<1; /* head load time */
 			if(pCMD->dma==0)
 				pCMD->cmd[SPEC_HLT]|=0x1; /* no dma */
 			pCMD->cmdlen=FDC_CMD_SPECIFY_LEN;
 			pCMD->resultlen=0;  /* no result */
 			break;
 		case FDC_CMD_DUMP_REG:
 			pCMD->cmdlen=FDC_CMD_DUMP_REG_LEN;
 			pCMD->resultlen=10;  /* 10 byte result */
 			break;
 		case FDC_CMD_READ_ID:
 			pCMD->cmd[COMMAND]|=(FDC_MFM_MODE<<6); /* set MFM bit */
 			pCMD->cmdlen=FDC_CMD_READ_ID_LEN;
 			pCMD->resultlen=7;  /* 7 byte result */
 			break;
 		case FDC_CMD_RECALIBRATE:
 			pCMD->cmd[DRIVE]&=0x03; /* don't set the head bit */
 			pCMD->cmdlen=FDC_CMD_RECALIBRATE_LEN;
 			pCMD->resultlen=0;  /* no result */
 			break;
 			break;
 		case FDC_CMD_SENSE_INT:
 			pCMD->cmdlen=FDC_CMD_SENSE_INT_LEN;
 			pCMD->resultlen=2;
 			break;
 	}
 	for(i=0;i<pCMD->cmdlen;i++) {
 		/* PRINTF("write cmd%d = 0x%02X\n",i,pCMD->cmd[i]); */
 		if (write_fdc_byte(pCMD->cmd[i]) == false) {
 			PRINTF("Error: timeout while issue cmd%d\n",i);
 			return false;
 		}
 	}
 	timeout=FDC_TIME_OUT;
 	for(i=0;i<pCMD->resultlen;i++) {
 		while((read_fdc_reg(FDC_MSR)&0xC0)!=0xC0) {
 			timeout--;
 			if(timeout==0) {
 				PRINTF(" timeout while reading result%d MSR=0x%02X\n",i,read_fdc_reg(FDC_MSR));
 				return false;
 			}
 		}
 		pCMD->result[i]=(unsigned char)read_fdc_byte();
 	}
 	return true;
 }

 /* selects the drive assigned in the cmd structur and
    switches on the Motor */
 void select_fdc_drive(FDC_COMMAND_STRUCT *pCMD)
 {
 	unsigned char val;

 	val=(1<<(4+pCMD->drive))|pCMD->drive|0xC; /* set reset, dma gate and motor bits */
 	if((read_fdc_reg(FDC_DOR)&val)!=val) {
 		write_fdc_reg(FDC_DOR,val);
 		for(val=0;val<255;val++)
 			udelay(500); /* wait some time to start motor */
 	}
 }

 /* switches off the Motor of the specified drive */
 void stop_fdc_drive(FDC_COMMAND_STRUCT *pCMD)
 {
 	unsigned char val;

 	val=(1<<(4+pCMD->drive))|pCMD->drive; /* sets motor bits */
 	write_fdc_reg(FDC_DOR,(read_fdc_reg(FDC_DOR)&~val));
 }

 /* issues a recalibrate command, waits for interrupt and
  * issues a sense_interrupt */
 int fdc_recalibrate(FDC_COMMAND_STRUCT *pCMD,FD_GEO_STRUCT *pFG)
 {
 	pCMD->cmd[COMMAND]=FDC_CMD_RECALIBRATE;
 	if (fdc_issue_cmd(pCMD, pFG) == false)
 		return false;
 	while (wait_for_fdc_int() != true);

 	pCMD->cmd[COMMAND]=FDC_CMD_SENSE_INT;
 	return(fdc_issue_cmd(pCMD,pFG));
 }

 /* issues a recalibrate command, waits for interrupt and
  * issues a sense_interrupt */
 int fdc_seek(FDC_COMMAND_STRUCT *pCMD,FD_GEO_STRUCT *pFG)
 {
 	pCMD->cmd[COMMAND]=FDC_CMD_SEEK;
 	if (fdc_issue_cmd(pCMD, pFG) == false)
 		return false;
 	while (wait_for_fdc_int() != true);

 	pCMD->cmd[COMMAND]=FDC_CMD_SENSE_INT;
 	return(fdc_issue_cmd(pCMD,pFG));
 }

 /* terminates current command, by not servicing the FIFO
  * waits for interrupt and fills in the result bytes */
 int fdc_terminate(FDC_COMMAND_STRUCT *pCMD)
 {
 	int i;
 	for(i=0;i<100;i++)
 		udelay(500); /* wait 500usec for fifo overrun */
 	while((read_fdc_reg(FDC_SRA)&0x80)==0x00); /* wait as long as no int has occured */
 	for(i=0;i<7;i++) {
 		pCMD->result[i]=(unsigned char)read_fdc_byte();
 	}
 	return true;
 }

 /* reads data from FDC, seek commands are issued automatic */
 int fdc_read_data(unsigned char *buffer, unsigned long blocks,FDC_COMMAND_STRUCT *pCMD, FD_GEO_STRUCT *pFG)
 {
   /* first seek to start address */
 	unsigned long len,readblk,i,timeout,ii,offset;
 	unsigned char c,retriesrw,retriescal;
 	unsigned char *bufferw; /* working buffer */
 	int sect_size;
 	int flags;

 	flags=disable_interrupts(); /* switch off all Interrupts */
 	select_fdc_drive(pCMD); /* switch on drive */
 	sect_size=0x080<<pFG->sect_code;
 	retriesrw=0;
 	retriescal=0;
 	offset=0;
 	if (fdc_seek(pCMD, pFG) == false) {
 		stop_fdc_drive(pCMD);
 		if (flags)
 			enable_interrupts();
 		return false;
 	}
 	if((pCMD->result[STATUS_0]&0x20)!=0x20) {
 		printf("Seek error Status: %02X\n",pCMD->result[STATUS_0]);
 		stop_fdc_drive(pCMD);
 		if (flags)
 			enable_interrupts();
 		return false;
 	}
 	/* now determine the next seek point */
 	/*	lastblk=pCMD->blnr + blocks; */
 	/*	readblk=(pFG->head*pFG->sect)-(pCMD->blnr%(pFG->head*pFG->sect)); */
 	readblk=pFG->sect-(pCMD->blnr%pFG->sect);
 	PRINTF("1st nr of block possible read %ld start %ld\n",readblk,pCMD->blnr);
 	if(readblk>blocks) /* is end within 1st track */
 		readblk=blocks; /* yes, correct it */
 	PRINTF("we read %ld blocks start %ld\n",readblk,pCMD->blnr);
 	bufferw = &buffer[0]; /* setup working buffer */
 	do {
 retryrw:
 		len=sect_size * readblk;
 		pCMD->cmd[COMMAND]=FDC_CMD_READ;
 		if (fdc_issue_cmd(pCMD, pFG) == false) {
 			stop_fdc_drive(pCMD);
 			if (flags)
 				enable_interrupts();
 			return false;
 		}
 		for (i=0;i<len;i++) {
 			timeout=FDC_TIME_OUT;
 			do {
 				c=read_fdc_reg(FDC_MSR);
 				if((c&0xC0)==0xC0) {
 					bufferw[i]=read_fdc_reg(FDC_FIFO);
 					break;
 				}
 				if((c&0xC0)==0x80) { /* output */
 					PRINTF("Transfer error transferred: at %ld, MSR=%02X\n",i,c);
 					if(i>6) {
 						for(ii=0;ii<7;ii++) {
 							pCMD->result[ii]=bufferw[(i-7+ii)];
 						} /* for */
 					}
 					if(retriesrw++>FDC_RW_RETRIES) {
 						if (retriescal++>FDC_CAL_RETRIES) {
 							stop_fdc_drive(pCMD);
 							if (flags)
 								enable_interrupts();
 							return false;
 						}
 						else {
 							PRINTF(" trying to recalibrate Try %d\n",retriescal);
 							if (fdc_recalibrate(pCMD, pFG) == false) {
 								stop_fdc_drive(pCMD);
 								if (flags)
 									enable_interrupts();
 								return false;
 							}
 							retriesrw=0;
 							goto retrycal;
 						} /* else >FDC_CAL_RETRIES */
 					}
 					else {
 						PRINTF("Read retry %d\n",retriesrw);
 						goto retryrw;
 					} /* else >FDC_RW_RETRIES */
 				}/* if output */
 				timeout--;
 			} while (true);
 		} /* for len */
 		/* the last sector of a track or all data has been read,
 		 * we need to get the results */
 		fdc_terminate(pCMD);
 		offset+=(sect_size*readblk); /* set up buffer pointer */
 		bufferw = &buffer[offset];
 		pCMD->blnr+=readblk; /* update current block nr */
 		blocks-=readblk; /* update blocks */
 		if(blocks==0)
 			break; /* we are finish */
 		/* setup new read blocks */
 		/*	readblk=pFG->head*pFG->sect; */
 		readblk=pFG->sect;
 		if(readblk>blocks)
 			readblk=blocks;
 retrycal:
 		/* a seek is necessary */
 		if (fdc_seek(pCMD, pFG) == false) {
 			stop_fdc_drive(pCMD);
 			if (flags)
 				enable_interrupts();
 			return false;
 		}
 		if((pCMD->result[STATUS_0]&0x20)!=0x20) {
 			PRINTF("Seek error Status: %02X\n",pCMD->result[STATUS_0]);
 			stop_fdc_drive(pCMD);
 			return false;
 		}
 	} while (true); /* start over */
 	stop_fdc_drive(pCMD); /* switch off drive */
 	if (flags)
 		enable_interrupts();
 	return true;
 }

 /* Scan all drives and check if drive is present and disk is inserted */
 int fdc_check_drive(FDC_COMMAND_STRUCT *pCMD, FD_GEO_STRUCT *pFG)
 {
 	int i,drives,state;
   /* OK procedure of data book is satisfied.
 	 * trying to get some information over the drives */
 	state=0; /* no drives, no disks */
 	for(drives=0;drives<4;drives++) {
 		pCMD->drive=drives;
 		select_fdc_drive(pCMD);
 		pCMD->blnr=0; /* set to the 1st block */
 		if (fdc_recalibrate(pCMD, pFG) == false)
 			continue;
 		if((pCMD->result[STATUS_0]&0x10)==0x10)
 			continue;
 		/* ok drive connected check for disk */
 		state|=(1<<drives);
 		pCMD->blnr=pFG->size; /* set to the last block */
 		if (fdc_seek(pCMD, pFG) == false)
 			continue;
 		pCMD->blnr=0; /* set to the 1st block */
 		if (fdc_recalibrate(pCMD, pFG) == false)
 			continue;
 		pCMD->cmd[COMMAND]=FDC_CMD_READ_ID;
 		if (fdc_issue_cmd(pCMD, pFG) == false)
 			continue;
 		state|=(0x10<<drives);
 	}
 	stop_fdc_drive(pCMD);
 	for(i=0;i<4;i++) {
 		PRINTF("Floppy Drive %d %sconnected %sDisk inserted %s\n",i,
 			((state&(1<<i))==(1<<i)) ? "":"not ",
 			((state&(0x10<<i))==(0x10<<i)) ? "":"no ",
 			((state&(0x10<<i))==(0x10<<i)) ? pFG->name : "");
 	}
 	pCMD->flags=state;
 	return true;
 }


 /**************************************************************************
 * int fdc_setup
 * setup the fdc according the datasheet
 * assuming in PS2 Mode
 */
 int fdc_setup(int drive, FDC_COMMAND_STRUCT *pCMD, FD_GEO_STRUCT *pFG)
 {
 	int i;

 #ifdef CONFIG_SYS_FDC_HW_INIT
 	fdc_hw_init ();
 #endif
 	/* first, we reset the FDC via the DOR */
 	write_fdc_reg(FDC_DOR,0x00);
 	for(i=0; i<255; i++) /* then we wait some time */
 		udelay(500);
 	/* then, we clear the reset in the DOR */
 	pCMD->drive=drive;
 	select_fdc_drive(pCMD);
 	/* initialize the CCR */
 	write_fdc_reg(FDC_CCR,pFG->rate);
 	/* then initialize the DSR */
 	write_fdc_reg(FDC_DSR,pFG->rate);
 	if (wait_for_fdc_int() == false) {
 			PRINTF("Time Out after writing CCR\n");
 			return false;
 	}
 	/* now issue sense Interrupt and status command
 	 * assuming only one drive present (drive 0) */
 	pCMD->dma=0; /* we don't use any dma at all */
 	for(i=0;i<4;i++) {
 		/* issue sense interrupt for all 4 possible drives */
 		pCMD->cmd[COMMAND]=FDC_CMD_SENSE_INT;
 		if (fdc_issue_cmd(pCMD, pFG) == false) {
 			PRINTF("Sense Interrupt for drive %d failed\n",i);
 		}
 	}
 	/* issue the configure command */
 	pCMD->drive=drive;
 	select_fdc_drive(pCMD);
 	pCMD->cmd[COMMAND]=FDC_CMD_CONFIGURE;
 	if (fdc_issue_cmd(pCMD, pFG) == false) {
 		PRINTF(" configure timeout\n");
 		stop_fdc_drive(pCMD);
 		return false;
 	}
 	/* issue specify command */
 	pCMD->cmd[COMMAND]=FDC_CMD_SPECIFY;
 	if (fdc_issue_cmd(pCMD, pFG) == false) {
 		PRINTF(" specify timeout\n");
 		stop_fdc_drive(pCMD);
 		return false;

 	}
 	/* then, we clear the reset in the DOR */
 	/* fdc_check_drive(pCMD,pFG);	*/
 	/*	write_fdc_reg(FDC_DOR,0x04); */

 	return true;
 }

 /****************************************************************************
  * main routine do_fdcboot
  */
 int do_fdcboot (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
 	FD_GEO_STRUCT *pFG = (FD_GEO_STRUCT *)floppy_type;
 	FDC_COMMAND_STRUCT *pCMD = &cmd;
 	unsigned long addr,imsize;
 #if defined(CONFIG_IMAGE_FORMAT_LEGACY)
 	image_header_t *hdr;  /* used for fdc boot */
 #endif
 	unsigned char boot_drive;
 	int i,nrofblk;
 #if defined(CONFIG_FIT)
 	const void *fit_hdr = NULL;
 #endif

 	switch (argc) {
 	case 1:
 		addr = CONFIG_SYS_LOAD_ADDR;
 		boot_drive=CONFIG_SYS_FDC_DRIVE_NUMBER;
 		break;
 	case 2:
 		addr = simple_strtoul(argv[1], NULL, 16);
 		boot_drive=CONFIG_SYS_FDC_DRIVE_NUMBER;
 		break;
 	case 3:
 		addr = simple_strtoul(argv[1], NULL, 16);
 		boot_drive=simple_strtoul(argv[2], NULL, 10);
 		break;
 	default:
 		return CMD_RET_USAGE;
 	}
 	/* setup FDC and scan for drives  */
 	if (fdc_setup(boot_drive, pCMD, pFG) == false) {
 		printf("\n** Error in setup FDC **\n");
 		return 1;
 	}
 	if (fdc_check_drive(pCMD, pFG) == false) {
 		printf("\n** Error in check_drives **\n");
 		return 1;
 	}
 	if((pCMD->flags&(1<<boot_drive))==0) {
 		/* drive not available */
 		printf("\n** Drive %d not availabe **\n",boot_drive);
 		return 1;
 	}
 	if((pCMD->flags&(0x10<<boot_drive))==0) {
 		/* no disk inserted */
 		printf("\n** No disk inserted in drive %d **\n",boot_drive);
 		return 1;
 	}
 	/* ok, we have a valid source */
 	pCMD->drive=boot_drive;
 	/* read first block */
 	pCMD->blnr=0;
 	if (fdc_read_data((unsigned char *)addr, 1, pCMD, pFG) == false) {
 		printf("\nRead error:");
 		for(i=0;i<7;i++)
 			printf("result%d: 0x%02X\n",i,pCMD->result[i]);
 		return 1;
 	}

 	switch (genimg_get_format ((void *)addr)) {
 #if defined(CONFIG_IMAGE_FORMAT_LEGACY)
 	case IMAGE_FORMAT_LEGACY:
 		hdr = (image_header_t *)addr;
 		image_print_contents (hdr);

 		imsize = image_get_image_size (hdr);
 		break;
 #endif
 #if defined(CONFIG_FIT)
 	case IMAGE_FORMAT_FIT:
 		fit_hdr = (const void *)addr;
 		puts ("Fit image detected...\n");

 		imsize = fit_get_size (fit_hdr);
 		break;
 #endif
 	default:
 		puts ("** Unknown image type\n");
 		return 1;
 	}

 	nrofblk=imsize/512;
 	if((imsize%512)>0)
 		nrofblk++;
 	printf("Loading %ld Bytes (%d blocks) at 0x%08lx..\n",imsize,nrofblk,addr);
 	pCMD->blnr=0;
 	if (fdc_read_data((unsigned char *)addr, nrofblk, pCMD, pFG) == false) {
 		/* read image block */
 		printf("\nRead error:");
 		for(i=0;i<7;i++)
 			printf("result%d: 0x%02X\n",i,pCMD->result[i]);
 		return 1;
 	}
 	printf("OK %ld Bytes loaded.\n",imsize);

 	flush_cache (addr, imsize);

 #if defined(CONFIG_FIT)
 	/* This cannot be done earlier, we need complete FIT image in RAM first */
 	if (genimg_get_format ((void *)addr) == IMAGE_FORMAT_FIT) {
 		if (!fit_check_format (fit_hdr)) {
 			puts ("** Bad FIT image format\n");
 			return 1;
 		}
 		fit_print_contents (fit_hdr);
 	}
 #endif

 	/* Loading ok, update default load address */
 	load_addr = addr;

 	return bootm_maybe_autostart(cmdtp, argv[0]);
 }

 U_BOOT_CMD(
 	fdcboot,	3,	1,	do_fdcboot,
 	"boot from floppy device",
 	"loadAddr drive"
 );
	/*
	* (C) Copyright 2001
	* Denis Peter, MPL AG, d.peter@mpl.ch.
	*
	* SPDX-License-Identifier: GPL-2.0+
	*/
	/*
	* Floppy Disk support
	*/

	#include <common.h>
	#include <config.h>
	#include <command.h>
	#include <image.h>


	#undef FDC_DEBUG

	#ifdef FDC_DEBUG
	#define PRINTF(fmt,args...) printf (fmt ,##args)
	#else
	#define PRINTF(fmt,args...)
	#endif

	/#if defined(CONFIG_CMD_DATE) /
	/#include <rtc.h> /
	/#endif /

	typedef struct {
	int flags; /* connected drives ect */
	unsigned long blnr; /* Logical block nr */
	uchar drive; /* drive no */
	uchar cmdlen; /* cmd length */
	uchar cmd[16]; /* cmd desc */
	uchar dma; /* if > 0 dma enabled */
	uchar result[11]; /* status information */
	uchar resultlen; /* lenght of result */
	} FDC_COMMAND_STRUCT;

	/* flags: only the lower 8bit used:
	* bit 0 if set drive 0 is present
	* bit 1 if set drive 1 is present
	* bit 2 if set drive 2 is present
	* bit 3 if set drive 3 is present
	* bit 4 if set disk in drive 0 is inserted
	* bit 5 if set disk in drive 1 is inserted
	* bit 6 if set disk in drive 2 is inserted
	* bit 7 if set disk in drive 4 is inserted
	*/

	/* cmd indexes */
	#define COMMAND 0
	#define DRIVE 1
	#define CONFIG0 1
	#define SPEC_HUTSRT 1
	#define TRACK 2
	#define CONFIG1 2
	#define SPEC_HLT 2
	#define HEAD 3
	#define CONFIG2 3
	#define SECTOR 4
	#define SECTOR_SIZE 5
	#define LAST_TRACK 6
	#define GAP 7
	#define DTL 8
	/* result indexes */
	#define STATUS_0 0
	#define STATUS_PCN 1
	#define STATUS_1 1
	#define STATUS_2 2
	#define STATUS_TRACK 3
	#define STATUS_HEAD 4
	#define STATUS_SECT 5
	#define STATUS_SECT_SIZE 6


	/* Register addresses */
	#define FDC_BASE 0x3F0
	#define FDC_SRA FDC_BASE + 0 /* Status Register A */
	#define FDC_SRB FDC_BASE + 1 /* Status Register B */
	#define FDC_DOR FDC_BASE + 2 /* Digital Output Register */
	#define FDC_TDR FDC_BASE + 3 /* Tape Drive Register */
	#define FDC_DSR FDC_BASE + 4 /* Data rate Register */
	#define FDC_MSR FDC_BASE + 4 /* Main Status Register */
	#define FDC_FIFO FDC_BASE + 5 /* FIFO */
	#define FDC_DIR FDC_BASE + 6 /* Digital Input Register */
	#define FDC_CCR FDC_BASE + 7 /* Configuration Control */
	/* Commands */
	#define FDC_CMD_SENSE_INT 0x08
	#define FDC_CMD_CONFIGURE 0x13
	#define FDC_CMD_SPECIFY 0x03
	#define FDC_CMD_RECALIBRATE 0x07
	#define FDC_CMD_READ 0x06
	#define FDC_CMD_READ_TRACK 0x02
	#define FDC_CMD_READ_ID 0x0A
	#define FDC_CMD_DUMP_REG 0x0E
	#define FDC_CMD_SEEK 0x0F

	#define FDC_CMD_SENSE_INT_LEN 0x01
	#define FDC_CMD_CONFIGURE_LEN 0x04
	#define FDC_CMD_SPECIFY_LEN 0x03
	#define FDC_CMD_RECALIBRATE_LEN 0x02
	#define FDC_CMD_READ_LEN 0x09
	#define FDC_CMD_READ_TRACK_LEN 0x09
	#define FDC_CMD_READ_ID_LEN 0x02
	#define FDC_CMD_DUMP_REG_LEN 0x01
	#define FDC_CMD_SEEK_LEN 0x03

	#define FDC_FIFO_THR 0x0C
	#define FDC_FIFO_DIS 0x00
	#define FDC_IMPLIED_SEEK 0x01
	#define FDC_POLL_DIS 0x00
	#define FDC_PRE_TRK 0x00
	#define FDC_CONFIGURE FDC_FIFO_THR \| (FDC_POLL_DIS<<4) \| (FDC_FIFO_DIS<<5) \| (FDC_IMPLIED_SEEK << 6)
	#define FDC_MFM_MODE 0x01 /* MFM enable */
	#define FDC_SKIP_MODE 0x00 /* skip enable */

	#define FDC_TIME_OUT 100000 /* time out */
	#define FDC_RW_RETRIES 3 /* read write retries */
	#define FDC_CAL_RETRIES 3 /* calibration and seek retries */


	/* Disk structure */
	typedef struct {
	unsigned int size; /* nr of sectors total */
	unsigned int sect; /* sectors per track */
	unsigned int head; /* nr of heads */
	unsigned int track; /* nr of tracks */
	unsigned int stretch; /* !=0 means double track steps */
	unsigned char gap; /* gap1 size */
	unsigned char rate; /* data rate. \|= 0x40 for perpendicular */
	unsigned char spec1; /* stepping rate, head unload time */
	unsigned char fmt_gap;/* gap2 size */
	unsigned char hlt; /* head load time */
	unsigned char sect_code;/* Sector Size code */
	const char * name; /* used only for predefined formats */
	} FD_GEO_STRUCT;


	/* supported Floppy types (currently only one) */
	const static FD_GEO_STRUCT floppy_type[2] = {
	{ 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,16,2,"H1440" }, /* 7 1.44MB 3.5" */
	{ 0, 0,0, 0,0,0x00,0x00,0x00,0x00, 0,0,NULL }, /* end of table */
	};

	static FDC_COMMAND_STRUCT cmd; /* global command struct */

	/* If the boot drive number is undefined, we assume it's drive 0 */
	#ifndef CONFIG_SYS_FDC_DRIVE_NUMBER
	#define CONFIG_SYS_FDC_DRIVE_NUMBER 0
	#endif

	/* Hardware access */
	#ifndef CONFIG_SYS_ISA_IO_STRIDE
	#define CONFIG_SYS_ISA_IO_STRIDE 1
	#endif

	#ifndef CONFIG_SYS_ISA_IO_OFFSET
	#define CONFIG_SYS_ISA_IO_OFFSET 0
	#endif

	/* Supporting Functions */
	/* reads a Register of the FDC */
	unsigned char read_fdc_reg(unsigned int addr)
	{
	volatile unsigned char *val =
	(volatile unsigned char *)(CONFIG_SYS_ISA_IO_BASE_ADDRESS +
	(addr * CONFIG_SYS_ISA_IO_STRIDE) +
	CONFIG_SYS_ISA_IO_OFFSET);

	return val [0];
	}

	/* writes a Register of the FDC */
	void write_fdc_reg(unsigned int addr, unsigned char val)
	{
	volatile unsigned char *tmp =
	(volatile unsigned char *)(CONFIG_SYS_ISA_IO_BASE_ADDRESS +
	(addr * CONFIG_SYS_ISA_IO_STRIDE) +
	CONFIG_SYS_ISA_IO_OFFSET);
	tmp[0]=val;
	}

	/* waits for an interrupt (polling) */
	int wait_for_fdc_int(void)
	{
	unsigned long timeout;
	timeout = FDC_TIME_OUT;
	while((read_fdc_reg(FDC_SRA)&0x80)==0) {
	timeout--;
	udelay(10);
	if(timeout==0) /* timeout occured */
	return false;
	}
	return true;
	}

	/* reads a byte from the FIFO of the FDC and checks direction and RQM bit
	of the MSR. returns -1 if timeout, or byte if ok */
	int read_fdc_byte(void)
	{
	unsigned long timeout;
	timeout = FDC_TIME_OUT;
	while((read_fdc_reg(FDC_MSR)&0xC0)!=0xC0) {
	/* direction out and ready */
	udelay(10);
	timeout--;
	if(timeout==0) /* timeout occured */
	return -1;
	}
	return read_fdc_reg(FDC_FIFO);
	}

	/* if the direction of the FIFO is wrong, this routine is used to
	empty the FIFO. Should _not_ be used */
	int fdc_need_more_output(void)
	{
	unsigned char c;
	while((read_fdc_reg(FDC_MSR)&0xC0)==0xC0) {
	c=(unsigned char)read_fdc_byte();
	printf("Error: more output: %x\n",c);
	}
	return true;
	}


	/* writes a byte to the FIFO of the FDC and checks direction and RQM bit
	of the MSR */
	int write_fdc_byte(unsigned char val)
	{
	unsigned long timeout;
	timeout = FDC_TIME_OUT;
	while((read_fdc_reg(FDC_MSR)&0xC0)!=0x80) {
	/* direction in and ready for byte */
	timeout--;
	udelay(10);
	fdc_need_more_output();
	if(timeout==0) /* timeout occured */
	return false;
	}
	write_fdc_reg(FDC_FIFO,val);
	return true;
	}

	/* sets up all FDC commands and issues it to the FDC. If
	the command causes direct results (no Execution Phase)
	the result is be read as well. */

	int fdc_issue_cmd(FDC_COMMAND_STRUCT pCMD,FD_GEO_STRUCT pFG)
	{
	int i;
	unsigned long head,track,sect,timeout;
	track = pCMD->blnr / (pFG->sect * pFG->head); /* track nr */
	sect = pCMD->blnr % (pFG->sect * pFG->head); /* remaining blocks */
	head = sect / pFG->sect; /* head nr */
	sect = sect % pFG->sect; /* remaining blocks */
	sect++; /* sectors are 1 based */
	PRINTF("Cmd 0x%02x Track %ld, Head %ld, Sector %ld, Drive %d (blnr %ld)\n",
	pCMD->cmd[0],track,head,sect,pCMD->drive,pCMD->blnr);

	if(head\|=0) { /* max heads = 2 */
	pCMD->cmd[DRIVE]=pCMD->drive \| 0x04; /* head 1 */
	pCMD->cmd[HEAD]=(unsigned char) head; /* head register */
	}
	else {
	pCMD->cmd[DRIVE]=pCMD->drive; /* head 0 */
	pCMD->cmd[HEAD]=(unsigned char) head; /* head register */
	}
	pCMD->cmd[TRACK]=(unsigned char) track; /* track */
	switch (pCMD->cmd[COMMAND]) {
	case FDC_CMD_READ:
	pCMD->cmd[SECTOR]=(unsigned char) sect; /* sector */
	pCMD->cmd[SECTOR_SIZE]=pFG->sect_code; /* sector size code */
	pCMD->cmd[LAST_TRACK]=pFG->sect; /* End of track */
	pCMD->cmd[GAP]=pFG->gap; /* gap */
	pCMD->cmd[DTL]=0xFF; /* DTL */
	pCMD->cmdlen=FDC_CMD_READ_LEN;
	pCMD->cmd[COMMAND]\|=(FDC_MFM_MODE<<6); /* set MFM bit */
	pCMD->cmd[COMMAND]\|=(FDC_SKIP_MODE<<5); /* set Skip bit */
	pCMD->resultlen=0; /* result only after execution */
	break;
	case FDC_CMD_SEEK:
	pCMD->cmdlen=FDC_CMD_SEEK_LEN;
	pCMD->resultlen=0; /* no result */
	break;
	case FDC_CMD_CONFIGURE:
	pCMD->cmd[CONFIG0]=0;
	pCMD->cmd[CONFIG1]=FDC_CONFIGURE; /* FIFO Threshold, Poll, Enable FIFO */
	pCMD->cmd[CONFIG2]=FDC_PRE_TRK; /* Precompensation Track */
	pCMD->cmdlen=FDC_CMD_CONFIGURE_LEN;
	pCMD->resultlen=0; /* no result */
	break;
	case FDC_CMD_SPECIFY:
	pCMD->cmd[SPEC_HUTSRT]=pFG->spec1;
	pCMD->cmd[SPEC_HLT]=(pFG->hlt)<<1; /* head load time */
	if(pCMD->dma==0)
	pCMD->cmd[SPEC_HLT]\|=0x1; /* no dma */
	pCMD->cmdlen=FDC_CMD_SPECIFY_LEN;
	pCMD->resultlen=0; /* no result */
	break;
	case FDC_CMD_DUMP_REG:
	pCMD->cmdlen=FDC_CMD_DUMP_REG_LEN;
	pCMD->resultlen=10; /* 10 byte result */
	break;
	case FDC_CMD_READ_ID:
	pCMD->cmd[COMMAND]\|=(FDC_MFM_MODE<<6); /* set MFM bit */
	pCMD->cmdlen=FDC_CMD_READ_ID_LEN;
	pCMD->resultlen=7; /* 7 byte result */
	break;
	case FDC_CMD_RECALIBRATE:
	pCMD->cmd[DRIVE]&=0x03; /* don't set the head bit */
	pCMD->cmdlen=FDC_CMD_RECALIBRATE_LEN;
	pCMD->resultlen=0; /* no result */
	break;
	break;
	case FDC_CMD_SENSE_INT:
	pCMD->cmdlen=FDC_CMD_SENSE_INT_LEN;
	pCMD->resultlen=2;
	break;
	}
	for(i=0;i<pCMD->cmdlen;i++) {
	/* PRINTF("write cmd%d = 0x%02X\n",i,pCMD->cmd[i]); */
	if (write_fdc_byte(pCMD->cmd[i]) == false) {
	PRINTF("Error: timeout while issue cmd%d\n",i);
	return false;
	}
	}
	timeout=FDC_TIME_OUT;
	for(i=0;i<pCMD->resultlen;i++) {
	while((read_fdc_reg(FDC_MSR)&0xC0)!=0xC0) {
	timeout--;
	if(timeout==0) {
	PRINTF(" timeout while reading result%d MSR=0x%02X\n",i,read_fdc_reg(FDC_MSR));
	return false;
	}
	}
	pCMD->result[i]=(unsigned char)read_fdc_byte();
	}
	return true;
	}

	/* selects the drive assigned in the cmd structur and
	switches on the Motor */
	void select_fdc_drive(FDC_COMMAND_STRUCT *pCMD)
	{
	unsigned char val;

	val=(1<<(4+pCMD->drive))\|pCMD->drive\|0xC; /* set reset, dma gate and motor bits */
	if((read_fdc_reg(FDC_DOR)&val)!=val) {
	write_fdc_reg(FDC_DOR,val);
	for(val=0;val<255;val++)
	udelay(500); /* wait some time to start motor */
	}
	}

	/* switches off the Motor of the specified drive */
	void stop_fdc_drive(FDC_COMMAND_STRUCT *pCMD)
	{
	unsigned char val;

	val=(1<<(4+pCMD->drive))\|pCMD->drive; /* sets motor bits */
	write_fdc_reg(FDC_DOR,(read_fdc_reg(FDC_DOR)&~val));
	}

	/* issues a recalibrate command, waits for interrupt and
	* issues a sense_interrupt */
	int fdc_recalibrate(FDC_COMMAND_STRUCT pCMD,FD_GEO_STRUCT pFG)
	{
	pCMD->cmd[COMMAND]=FDC_CMD_RECALIBRATE;
	if (fdc_issue_cmd(pCMD, pFG) == false)
	return false;
	while (wait_for_fdc_int() != true);

	pCMD->cmd[COMMAND]=FDC_CMD_SENSE_INT;
	return(fdc_issue_cmd(pCMD,pFG));
	}

	/* issues a recalibrate command, waits for interrupt and
	* issues a sense_interrupt */
	int fdc_seek(FDC_COMMAND_STRUCT pCMD,FD_GEO_STRUCT pFG)
	{
	pCMD->cmd[COMMAND]=FDC_CMD_SEEK;
	if (fdc_issue_cmd(pCMD, pFG) == false)
	return false;
	while (wait_for_fdc_int() != true);

	pCMD->cmd[COMMAND]=FDC_CMD_SENSE_INT;
	return(fdc_issue_cmd(pCMD,pFG));
	}

	/* terminates current command, by not servicing the FIFO
	* waits for interrupt and fills in the result bytes */
	int fdc_terminate(FDC_COMMAND_STRUCT *pCMD)
	{
	int i;
	for(i=0;i<100;i++)
	udelay(500); /* wait 500usec for fifo overrun */
	while((read_fdc_reg(FDC_SRA)&0x80)==0x00); /* wait as long as no int has occured */
	for(i=0;i<7;i++) {
	pCMD->result[i]=(unsigned char)read_fdc_byte();
	}
	return true;
	}

	/* reads data from FDC, seek commands are issued automatic */
	int fdc_read_data(unsigned char buffer, unsigned long blocks,FDC_COMMAND_STRUCT pCMD, FD_GEO_STRUCT *pFG)
	{
	/* first seek to start address */
	unsigned long len,readblk,i,timeout,ii,offset;
	unsigned char c,retriesrw,retriescal;
	unsigned char bufferw; / working buffer */
	int sect_size;
	int flags;

	flags=disable_interrupts(); /* switch off all Interrupts */
	select_fdc_drive(pCMD); /* switch on drive */
	sect_size=0x080<<pFG->sect_code;
	retriesrw=0;
	retriescal=0;
	offset=0;
	if (fdc_seek(pCMD, pFG) == false) {
	stop_fdc_drive(pCMD);
	if (flags)
	enable_interrupts();
	return false;
	}
	if((pCMD->result[STATUS_0]&0x20)!=0x20) {
	printf("Seek error Status: %02X\n",pCMD->result[STATUS_0]);
	stop_fdc_drive(pCMD);
	if (flags)
	enable_interrupts();
	return false;
	}
	/* now determine the next seek point */
	/* lastblk=pCMD->blnr + blocks; */
	/* readblk=(pFG->headpFG->sect)-(pCMD->blnr%(pFG->headpFG->sect)); */
	readblk=pFG->sect-(pCMD->blnr%pFG->sect);
	PRINTF("1st nr of block possible read %ld start %ld\n",readblk,pCMD->blnr);
	if(readblk>blocks) /* is end within 1st track */
	readblk=blocks; /* yes, correct it */
	PRINTF("we read %ld blocks start %ld\n",readblk,pCMD->blnr);
	bufferw = &buffer[0]; /* setup working buffer */
	do {
	retryrw:
	len=sect_size * readblk;
	pCMD->cmd[COMMAND]=FDC_CMD_READ;
	if (fdc_issue_cmd(pCMD, pFG) == false) {
	stop_fdc_drive(pCMD);
	if (flags)
	enable_interrupts();
	return false;
	}
	for (i=0;i<len;i++) {
	timeout=FDC_TIME_OUT;
	do {
	c=read_fdc_reg(FDC_MSR);
	if((c&0xC0)==0xC0) {
	bufferw[i]=read_fdc_reg(FDC_FIFO);
	break;
	}
	if((c&0xC0)==0x80) { /* output */
	PRINTF("Transfer error transferred: at %ld, MSR=%02X\n",i,c);
	if(i>6) {
	for(ii=0;ii<7;ii++) {
	pCMD->result[ii]=bufferw[(i-7+ii)];
	} /* for */
	}
	if(retriesrw++>FDC_RW_RETRIES) {
	if (retriescal++>FDC_CAL_RETRIES) {
	stop_fdc_drive(pCMD);
	if (flags)
	enable_interrupts();
	return false;
	}
	else {
	PRINTF(" trying to recalibrate Try %d\n",retriescal);
	if (fdc_recalibrate(pCMD, pFG) == false) {
	stop_fdc_drive(pCMD);
	if (flags)
	enable_interrupts();
	return false;
	}
	retriesrw=0;
	goto retrycal;
	} /* else >FDC_CAL_RETRIES */
	}
	else {
	PRINTF("Read retry %d\n",retriesrw);
	goto retryrw;
	} /* else >FDC_RW_RETRIES */
	}/* if output */
	timeout--;
	} while (true);
	} /* for len */
	/* the last sector of a track or all data has been read,
	* we need to get the results */
	fdc_terminate(pCMD);
	offset+=(sect_sizereadblk); / set up buffer pointer */
	bufferw = &buffer[offset];
	pCMD->blnr+=readblk; /* update current block nr */
	blocks-=readblk; /* update blocks */
	if(blocks==0)
	break; /* we are finish */
	/* setup new read blocks */
	/* readblk=pFG->headpFG->sect; /
	readblk=pFG->sect;
	if(readblk>blocks)
	readblk=blocks;
	retrycal:
	/* a seek is necessary */
	if (fdc_seek(pCMD, pFG) == false) {
	stop_fdc_drive(pCMD);
	if (flags)
	enable_interrupts();
	return false;
	}
	if((pCMD->result[STATUS_0]&0x20)!=0x20) {
	PRINTF("Seek error Status: %02X\n",pCMD->result[STATUS_0]);
	stop_fdc_drive(pCMD);
	return false;
	}
	} while (true); /* start over */
	stop_fdc_drive(pCMD); /* switch off drive */
	if (flags)
	enable_interrupts();
	return true;
	}

	/* Scan all drives and check if drive is present and disk is inserted */
	int fdc_check_drive(FDC_COMMAND_STRUCT pCMD, FD_GEO_STRUCT pFG)
	{
	int i,drives,state;
	/* OK procedure of data book is satisfied.
	* trying to get some information over the drives */
	state=0; /* no drives, no disks */
	for(drives=0;drives<4;drives++) {
	pCMD->drive=drives;
	select_fdc_drive(pCMD);
	pCMD->blnr=0; /* set to the 1st block */
	if (fdc_recalibrate(pCMD, pFG) == false)
	continue;
	if((pCMD->result[STATUS_0]&0x10)==0x10)
	continue;
	/* ok drive connected check for disk */
	state\|=(1<<drives);
	pCMD->blnr=pFG->size; /* set to the last block */
	if (fdc_seek(pCMD, pFG) == false)
	continue;
	pCMD->blnr=0; /* set to the 1st block */
	if (fdc_recalibrate(pCMD, pFG) == false)
	continue;
	pCMD->cmd[COMMAND]=FDC_CMD_READ_ID;
	if (fdc_issue_cmd(pCMD, pFG) == false)
	continue;
	state\|=(0x10<<drives);
	}
	stop_fdc_drive(pCMD);
	for(i=0;i<4;i++) {
	PRINTF("Floppy Drive %d %sconnected %sDisk inserted %s\n",i,
	((state&(1<<i))==(1<<i)) ? "":"not ",
	((state&(0x10<<i))==(0x10<<i)) ? "":"no ",
	((state&(0x10<<i))==(0x10<<i)) ? pFG->name : "");
	}
	pCMD->flags=state;
	return true;
	}


	/**************************************************************************
	* int fdc_setup
	* setup the fdc according the datasheet
	* assuming in PS2 Mode
	*/
	int fdc_setup(int drive, FDC_COMMAND_STRUCT pCMD, FD_GEO_STRUCT pFG)
	{
	int i;

	#ifdef CONFIG_SYS_FDC_HW_INIT
	fdc_hw_init ();
	#endif
	/* first, we reset the FDC via the DOR */
	write_fdc_reg(FDC_DOR,0x00);
	for(i=0; i<255; i++) /* then we wait some time */
	udelay(500);
	/* then, we clear the reset in the DOR */
	pCMD->drive=drive;
	select_fdc_drive(pCMD);
	/* initialize the CCR */
	write_fdc_reg(FDC_CCR,pFG->rate);
	/* then initialize the DSR */
	write_fdc_reg(FDC_DSR,pFG->rate);
	if (wait_for_fdc_int() == false) {
	PRINTF("Time Out after writing CCR\n");
	return false;
	}
	/* now issue sense Interrupt and status command
	* assuming only one drive present (drive 0) */
	pCMD->dma=0; /* we don't use any dma at all */
	for(i=0;i<4;i++) {
	/* issue sense interrupt for all 4 possible drives */
	pCMD->cmd[COMMAND]=FDC_CMD_SENSE_INT;
	if (fdc_issue_cmd(pCMD, pFG) == false) {
	PRINTF("Sense Interrupt for drive %d failed\n",i);
	}
	}
	/* issue the configure command */
	pCMD->drive=drive;
	select_fdc_drive(pCMD);
	pCMD->cmd[COMMAND]=FDC_CMD_CONFIGURE;
	if (fdc_issue_cmd(pCMD, pFG) == false) {
	PRINTF(" configure timeout\n");
	stop_fdc_drive(pCMD);
	return false;
	}
	/* issue specify command */
	pCMD->cmd[COMMAND]=FDC_CMD_SPECIFY;
	if (fdc_issue_cmd(pCMD, pFG) == false) {
	PRINTF(" specify timeout\n");
	stop_fdc_drive(pCMD);
	return false;

	}
	/* then, we clear the reset in the DOR */
	/* fdc_check_drive(pCMD,pFG); */
	/* write_fdc_reg(FDC_DOR,0x04); */

	return true;
	}

	/****************************************************************************
	* main routine do_fdcboot
	*/
	int do_fdcboot (cmd_tbl_t cmdtp, int flag, int argc, char const argv[])
	{
	FD_GEO_STRUCT pFG = (FD_GEO_STRUCT )floppy_type;
	FDC_COMMAND_STRUCT *pCMD = &cmd;
	unsigned long addr,imsize;
	#if defined(CONFIG_IMAGE_FORMAT_LEGACY)
	image_header_t hdr; / used for fdc boot */
	#endif
	unsigned char boot_drive;
	int i,nrofblk;
	#if defined(CONFIG_FIT)
	const void *fit_hdr = NULL;
	#endif

	switch (argc) {
	case 1:
	addr = CONFIG_SYS_LOAD_ADDR;
	boot_drive=CONFIG_SYS_FDC_DRIVE_NUMBER;
	break;
	case 2:
	addr = simple_strtoul(argv[1], NULL, 16);
	boot_drive=CONFIG_SYS_FDC_DRIVE_NUMBER;
	break;
	case 3:
	addr = simple_strtoul(argv[1], NULL, 16);
	boot_drive=simple_strtoul(argv[2], NULL, 10);
	break;
	default:
	return CMD_RET_USAGE;
	}
	/* setup FDC and scan for drives */
	if (fdc_setup(boot_drive, pCMD, pFG) == false) {
	printf("\n Error in setup FDC \n");
	return 1;
	}
	if (fdc_check_drive(pCMD, pFG) == false) {
	printf("\n Error in check_drives \n");
	return 1;
	}
	if((pCMD->flags&(1<<boot_drive))==0) {
	/* drive not available */
	printf("\n Drive %d not availabe \n",boot_drive);
	return 1;
	}
	if((pCMD->flags&(0x10<<boot_drive))==0) {
	/* no disk inserted */
	printf("\n No disk inserted in drive %d \n",boot_drive);
	return 1;
	}
	/* ok, we have a valid source */
	pCMD->drive=boot_drive;
	/* read first block */
	pCMD->blnr=0;
	if (fdc_read_data((unsigned char *)addr, 1, pCMD, pFG) == false) {
	printf("\nRead error:");
	for(i=0;i<7;i++)
	printf("result%d: 0x%02X\n",i,pCMD->result[i]);
	return 1;
	}

	switch (genimg_get_format ((void *)addr)) {
	#if defined(CONFIG_IMAGE_FORMAT_LEGACY)
	case IMAGE_FORMAT_LEGACY:
	hdr = (image_header_t *)addr;
	image_print_contents (hdr);

	imsize = image_get_image_size (hdr);
	break;
	#endif
	#if defined(CONFIG_FIT)
	case IMAGE_FORMAT_FIT:
	fit_hdr = (const void *)addr;
	puts ("Fit image detected...\n");

	imsize = fit_get_size (fit_hdr);
	break;
	#endif
	default:
	puts ("** Unknown image type\n");
	return 1;
	}

	nrofblk=imsize/512;
	if((imsize%512)>0)
	nrofblk++;
	printf("Loading %ld Bytes (%d blocks) at 0x%08lx..\n",imsize,nrofblk,addr);
	pCMD->blnr=0;
	if (fdc_read_data((unsigned char *)addr, nrofblk, pCMD, pFG) == false) {
	/* read image block */
	printf("\nRead error:");
	for(i=0;i<7;i++)
	printf("result%d: 0x%02X\n",i,pCMD->result[i]);
	return 1;
	}
	printf("OK %ld Bytes loaded.\n",imsize);

	flush_cache (addr, imsize);

	#if defined(CONFIG_FIT)
	/* This cannot be done earlier, we need complete FIT image in RAM first */
	if (genimg_get_format ((void *)addr) == IMAGE_FORMAT_FIT) {
	if (!fit_check_format (fit_hdr)) {
	puts ("** Bad FIT image format\n");
	return 1;
	}
	fit_print_contents (fit_hdr);
	}
	#endif

	/* Loading ok, update default load address */
	load_addr = addr;

	return bootm_maybe_autostart(cmdtp, argv[0]);
	}

	U_BOOT_CMD(
	fdcboot, 3, 1, do_fdcboot,
	"boot from floppy device",
	"loadAddr drive"
	);