Initial revision

1 files changed, 735 insertions, 0 deletions

diff --git a/common/cmd_fdc.c b/common/cmd_fdc.c
new file mode 100644
index 0000000..712c14b
--- /dev/null
+++ b/common/cmd_fdc.c
@@ -0,0 +1,735 @@
+/*
+ * (C) Copyright 2001
+ * Denis Peter, MPL AG, d.peter@mpl.ch.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ *
+ */
+/*
+ * 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
+
+#ifndef	TRUE
+#define TRUE            1
+#endif
+#ifndef FALSE
+#define FALSE           0
+#endif
+
+
+#if (CONFIG_COMMANDS & CFG_CMD_DATE)
+#include <rtc.h>
+#endif
+
+#if (CONFIG_COMMANDS & CFG_CMD_FDC)
+
+
+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 */
+
+/* Supporting Functions */
+/* reads a Register of the FDC */
+unsigned char read_fdc_reg(unsigned int addr)
+{
+	volatile unsigned char *val = (volatile unsigned char *)(CFG_ISA_IO_BASE_ADDRESS | addr);
+	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 *)(CFG_ISA_IO_BASE_ADDRESS | addr);
+		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("Track %ld, Head %ld, Sector %ld, Drive %d (blnr %ld)\n",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,lastblk,readblk,i,timeout,ii,offset;
+	unsigned char pcn,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);
+		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);
+		enable_interrupts();
+		return FALSE;
+	}
+	pcn=pCMD->result[STATUS_PCN]; /* current track */
+	/* 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);
+			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 transfered: 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);
+							enable_interrupts();
+							return FALSE;
+						}
+						else {
+							PRINTF(" trying to recalibrate Try %d\n",retriescal);
+							if(fdc_recalibrate(pCMD,pFG)==FALSE) {
+								stop_fdc_drive(pCMD);
+								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);
+			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;
+		}
+		pcn=pCMD->result[STATUS_PCN]; /* current track */
+	}while(TRUE); /* start over */
+	stop_fdc_drive(pCMD); /* switch off drive */
+	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)
+			break;
+		if((pCMD->result[STATUS_0]&0x10)==0x10)
+			break;
+		/* ok drive connected check for disk */
+		state|=(1<<drives);
+		pCMD->blnr=pFG->size; /* set to the last block */
+		if(fdc_seek(pCMD,pFG)==FALSE)
+			break;
+		pCMD->blnr=0; /* set to the 1st block */
+		if(fdc_recalibrate(pCMD,pFG)==FALSE)
+			break;
+		pCMD->cmd[COMMAND]=FDC_CMD_READ_ID;
+		if(fdc_issue_cmd(pCMD,pFG)==FALSE)
+			break;
+		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(FDC_COMMAND_STRUCT *pCMD,	FD_GEO_STRUCT *pFG)
+{
+
+	int i;
+	/* 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=0;
+	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);
+		}
+	}
+	/* assuming drive 0 for rest of configuration
+	 * issue the configure command */
+	pCMD->drive=0;
+	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 *argv[])
+{
+	FD_GEO_STRUCT *pFG = (FD_GEO_STRUCT *)floppy_type;
+	FDC_COMMAND_STRUCT *pCMD = &cmd;
+ 	unsigned long addr,imsize;
+	image_header_t *hdr;  /* used for fdc boot */
+	unsigned char boot_drive;
+	int i,nrofblk;
+	char *ep;
+	int rcode = 0;
+
+	switch (argc) {
+	case 1:
+		addr = CFG_LOAD_ADDR;
+		boot_drive=0; /* default boot from drive 0 */
+		break;
+	case 2:
+		addr = simple_strtoul(argv[1], NULL, 16);
+		boot_drive=0; /* default boot from drive 0 */
+		break;
+	case 3:
+		addr = simple_strtoul(argv[1], NULL, 16);
+		boot_drive=simple_strtoul(argv[2], NULL, 10);
+		break;
+	default:
+		printf ("Usage:\n%s\n", cmdtp->usage);
+		return 1;
+	}
+	/* setup FDC and scan for drives  */
+	if(fdc_setup(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;
+	}
+	hdr = (image_header_t *)addr;
+	if (hdr->ih_magic  != IH_MAGIC) {
+		printf ("Bad Magic Number\n");
+		return 1;
+	}
+	print_image_hdr(hdr);
+
+	imsize= hdr->ih_size+sizeof(image_header_t);
+	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);
+	/* Loading ok, update default load address */
+
+	load_addr = addr;
+	if(hdr->ih_type  == IH_TYPE_KERNEL) {
+		/* Check if we should attempt an auto-start */
+		if (((ep = getenv("autostart")) != NULL) && (strcmp(ep,"yes") == 0)) {
+			char *local_args[2];
+			extern int do_bootm (cmd_tbl_t *, int, int, char *[]);
+
+			local_args[0] = argv[0];
+			local_args[1] = NULL;
+
+			printf ("Automatic boot of image at addr 0x%08lX ...\n", addr);
+
+			do_bootm (cmdtp, 0, 1, local_args);
+			rcode ++;
+		}
+	}
+	return rcode;
+}
+
+
+
+#endif /* CONFIG_COMMANDS & CFG_CMD_FDC */
+
+