os/linux-2.6-tag--devboard-R2_10-4/arch/cris/arch-v32/drivers/elphel/fpgajtag.c

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/*!***************************************************************************
*! FILE NAME  : fpgajtag353.c
*! DESCRIPTION: TBD
*! Copyright 2002-2007 (C) Elphel, Inc.
*! -----------------------------------------------------------------------------**
*!
*!  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 3 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, see <http://www.gnu.org/licenses/>.
*! -----------------------------------------------------------------------------**
*!  $Log: fpgajtag353.c,v $
*!  Revision 1.2  2008/04/11 23:16:51  elphel
*!  removed unneeded local_irq_disable() after local_irq_save_flags()
*!
*!  Revision 1.1.1.1  2007/08/17 10:23:18  elphel
*!  This is a fresh tree based on elphel353-2.10
*!
*!  Revision 1.7  2007/08/17 10:23:18  spectr_rain
*!  switch to GPL3 license
*!
*!  Revision 1.6  2007/07/20 10:17:46  spectr_rain
*!  *** empty log message ***
*!
*!  Revision 1.5  2007/06/28 02:20:39  elphel
*!  Slowed down sensor FPGA programming while working with long cables. Problem was different, so maybe that change may be undone.
*!
*!  Revision 1.4  2007/05/21 21:23:50  elphel
*!  remove compile-time warning
*!
*!  Revision 1.3  2007/05/21 17:45:11  elphel
*!  boundary scan support, added 359/347 detection
*!
*!  Revision 1.2  2007/03/25 10:14:23  elphel
*!  Accommodating 10359 board
*!
*!  Revision 1.1.1.1  2007/02/23 10:11:48  elphel
*!  initial import into CVS
*!
*!  Revision 1.2  2005/05/10 21:08:49  elphel
*!  *** empty log message ***
*!

TODO: replace static buffer (what a waste!)
I suspect "somebody" is is playing with portA during JTAG configuration.
To test that I'll use 256K static buffer, copy all the bitstream there,
disable interrupts and do the programming.
No debug with printk ... 
*/

/****************** INCLUDE FILES SECTION ***********************************/
#include <linux/autoconf.h>

#include <linux/module.h>
#include <linux/sched.h>
#include <linux/slab.h>
   #include <linux/ioport.h> // needed?
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/string.h>
//#include <linux/poll.h>
#include <linux/init.h>

//#include <linux/interrupt.h>
//#include <linux/spinlock.h>


//#include <asm/svinto.h> - obsolete

// #include <asm/etraxgpio.h> // probably just for gpio driver
#include <asm/arch/hwregs/reg_map.h>
#include <asm/arch/hwregs/reg_rdwr.h>
#include <asm/arch/hwregs/gio_defs.h>
#include <asm/arch/hwregs/intr_vect_defs.h>
#include <asm/arch/hwregs/pinmux_defs.h>


#include <asm/io.h>
#include <asm/system.h>
#include <asm/irq.h>

#include <asm/elphel/fpgactrl.h> //defines for fpga_state fields


#include <asm/delay.h>
#include <asm/uaccess.h>

#include "fpgactrl.h" // extern fpga_state, defines port_csp0_addr, port_csp4_addr
#include "x3x3.h"     // FPGA registers and macros


//#include <asm/fpgaconfa.h>


//#define JTAG_DISABLE_IRQ y

#define D(x)
//#define D(x) printk("%s:%d:",__FILE__,__LINE__);x

/*
port C 353:
 0 - TDO  (in)
 1 - TDI  (out)
 2 - TMS  (out)
 3 - TCK  (out)
 4 - NC (was INIT (i/o) )
 5 - DONE (in)
 6 - RSTBTN
 7 - PGM  (out)
*/
#define FPGAJTAG_TDO_BIT 0
#define FPGAJTAG_TDI_BIT 1
#define FPGAJTAG_TMS_BIT 2
#define FPGAJTAG_TCK_BIT 3
#define FPGAJTAG_DONE_BIT 5
#define FPGAJTAG_RSTBTN_BIT 6
#define FPGAJTAG_PGM_BIT 7


#ifndef XC2S300E_BITSIZE
  #define XC3S1000_BITSIZE  3223488
  #define XC3S1200E_BITSIZE 3841189
  #define XC3S1200E_BOUNDARY_SIZE 772
//  #define XC3S1200E_BOUNDARY_SIZE 812
  #define FJTAG_BUF_SIZE 0x77000
  #define FJTAG_MAX_HEAD 0x1000
  #define FJTAG_RAW_WSIZE 0x40000 // shared with  bitstream buffer
  #define FJTAG_RAW_RSIZE 0x30000 // shared with  bitstream buffer
  #define FJTAG_IDSIZE    0x40    // bits - ID and User

#endif

//=========================
#define FPGA_JTAG_MAJOR 132  /* LOCAL/EXPERIMENTAL */
#define FPGA_JTAG_DRIVER_NAME "Elphel (R) model 353 FPGA (Xilinx (R) XC3S1200E) configuration driver"
#define FPGA_JTAG_MAXMINOR 10
#define FPGA_JTAG_RESET_MINOR   0  // just close open files
#define FPGA_JTAG_RAW_MINOR 0  // just close open files
#define FPGA_JTAG_MINOR     1
#define FPGA_SJTAG_MINOR    2
#define FPGA_AJTAG_MINOR    3

#define FPGA_JTAG_BOUNDARY_MINOR    5  // read/write boundary pins of the main FPGA
#define FPGA_SJTAG_BOUNDARY_MINOR   6  // read/write boundary pins of the sensor board FPGA
#define FPGA_AJTAG_BOUNDARY_MINOR   7  // read/write boundary pins of the aux board FPGA

#define JTAG_RAW         0 // raw JTAG access to any FPGA
#define JTAG_MAIN_FPGA   1 // main board FPGA access  (10353)
#define JTAG_SENSOR_FPGA 2 // sensor board FPGA access (10347, 10359) 
#define JTAG_AUX_FPGA    3 // 
#define JTAG_NCHANNELS 4

#define JTAG_MODE_CLOSED   0 // JTAG channel is closed
#define JTAG_MODE_RDID     1 // JTAG channel read ID
#define JTAG_MODE_PGM      2 // JTAG channel PROGRAM
#define JTAG_MODE_BOUNDARY 3 // JTAG channel boundary scan (just opened, will become one of the 2:JTAG_MODE_SAMPLE, JTAG_MODE_EXTEST
#define JTAG_MODE_SAMPLE   4 // JTAG channel boundary scan - sample (the first operation after open is read)
#define JTAG_MODE_EXTEST   5 // JTAG channel boundary scan - EXTEST (the first operation after open is read)
#define JTAG_MODE_RAW      6 // JTAG raw command mode

// configuration and raw minors use whole buffer, ID and boundary can be opened at the same time
struct JTAG_channel_t {
  int mode; // 0..5 -JTAG_MODE_CLOSED...JTAG_MODE_EXTEST
  unsigned char * dbuf; // data buffer (shared, boundary mode use different parts)
  int sizew;            // byte size that can be written
  int sizer;            // byte size that can be read
  int bitsw;            // bit size to be written
  int bitsr;            // bit size to be read
  int wp;               // byte pointer for file write
  int rp;               // byte pointer for file read
  int wdirty;           // some data is buffered but not yet sent out in EXTEST mode
};
static unsigned char  bitstream_data[FJTAG_BUF_SIZE];    // will fit bitstream and the header (if any). Also used for boundary write
//static unsigned short *raw_fifo_w= (unsigned short) &bitstream_data[0];
static unsigned char *raw_fifo_w=  &bitstream_data[0];
static unsigned char *raw_fifo_r=  &bitstream_data[FJTAG_RAW_WSIZE];
static struct  JTAG_channel_t JTAG_channels[JTAG_NCHANNELS];
// boundary scan is read always at open. written - at close (only if there were any writes)
static int data_modified=0;

static reg_gio_rw_pc_dout  pc_dout;
#define PC_DOUT_INITIAL 0
//static        int buf8i=0;    // current buffer length (in bytes!)
//static  int datastart=0;
//static int prev32;
//static int prev64;

//static int fpga_jtag_state=0; 

// inteface functions
static const char fpga_jtag_name[] = "fpga_jtag_loader";
static int minors[FPGA_JTAG_MAXMINOR+1];        // each minor can be opened only once
//static int thisminor;
static int     fpga_jtag_open   (struct inode *inode, struct file *filp);
static int     fpga_jtag_release(struct inode *inode, struct file *filp);
static ssize_t fpga_jtag_write  (struct file * file, const char * buf, size_t count, loff_t *off);
static loff_t  fpga_jtag_lseek  (struct file * file, loff_t offset, int orig);
static ssize_t fpga_jtag_read   (struct file * file, char * buf, size_t count, loff_t *off);
static int __init fpga_jtag_init(void);

static struct file_operations fpga_jtag_fops = {
        owner:    THIS_MODULE,
        open:     fpga_jtag_open,
        release:  fpga_jtag_release,
        llseek:   fpga_jtag_lseek,
        read:     fpga_jtag_read,
        write:    fpga_jtag_write
};



// internal functions
loff_t fjtag_bitsize (int minor);
loff_t fjtag_bytesize (int minor);
int JTAG_channel(int minor);
void initPortC(void);
void set_pgm_mode (int chn, int en);
void set_pgm (int chn, int pgmon);
int read_done (int chn);
int jtag_send (int chn, int tms, int len, int d);
int jtag_write_bits (int chn,
                     unsigned char *buf, // data to write
                     int len,            // number of bytes to write
                     int check,          // compare readback data with previously written, abort on mismatch
                     int last,           // output last bit with TMS=1
                     int prev[2]);       // if null - don't use
int JTAG_configure (int chn, unsigned char * buf, int len);
int JTAG_readID (int chn, unsigned char * buf);
int JTAG_openChannel (int chn);
int JTAG_resetChannel (int chn);
int JTAG_CAPTURE (int chn, unsigned char * buf, int len);
int JTAG_EXTEST (int chn, unsigned char * buf, int len);

void JTAG_push_raw (int b);
int JTAG_process_raw(void);


int JTAG_channel(int minor) {
  switch (minor) {
    case FPGA_JTAG_RESET_MINOR : // same as RAW
        return JTAG_RAW;
    case FPGA_JTAG_MINOR:
    case FPGA_JTAG_BOUNDARY_MINOR:
        return JTAG_MAIN_FPGA;
    case FPGA_SJTAG_MINOR:
    case FPGA_SJTAG_BOUNDARY_MINOR:
        return JTAG_SENSOR_FPGA;
    case FPGA_AJTAG_MINOR:
    case FPGA_AJTAG_BOUNDARY_MINOR:
        return JTAG_AUX_FPGA;
  }
  return 0;
}
static int raw_fifo_w_wp;
static int raw_fifo_w_rp;
static int raw_fifo_r_wp;
static int raw_fifo_r_rp;
static int raw_chn;

/*
 * send raw JTAG commands. Each command consists of 2 bytes
 * byte 0 - data to send through TDI, lsb aligned (if less than 8 bits - hign bits are not used
 * byte 1 - 0001TNNN - send NNN?NNN:8 bits of byte 0 through TDI, keeping TDS at value of T (reads back TDO - before TCL)
 *        - 00100000 - select JTAG channel from byte 0 (reads back channel)
 *        - 00100010 - de-activate JTAG access         (reads back 0)
 *        - 00100011 - activate JTAG access            (reads back 0)
 *        - 00100100 - PGM off                         (reads back ready in bit 0)
 *        - 00100101 - PGM on                          (reads back 0xf0)
 *        - 1TTTTTTT - delay usec byte0+ ((byte1 &0x7f) << 8)  (reads back 80)
 *        - 0??????? (other) - nop                     (reads back 0xff)
 * if no channel is selected, no output is generated
void set_pgm_mode (int chn, int en);
void set_pgm (int chn, int pgmon);
 */
#define JTAG_RAW_SEND   0x10
#define JTAG_RAW_SETCHN 0x20
#define JTAG_RAW_DEACT  0x22
#define JTAG_RAW_ACT    0x23
#define JTAG_RAW_PGMOFF 0x24
#define JTAG_RAW_PGMON  0x25
#define JTAG_RAW_WAIT   0x80

void JTAG_push_raw (int b) {
  raw_fifo_r[raw_fifo_r_wp++]=b;
  if (raw_fifo_r_wp > FJTAG_RAW_RSIZE) raw_fifo_r_wp-=FJTAG_RAW_RSIZE;
}
int JTAG_process_raw(void) {
  unsigned char b0, b1;
  while (raw_fifo_w_rp != (raw_fifo_w_wp & ~1)) {
    b0=raw_fifo_w[raw_fifo_w_rp++];
    b1=raw_fifo_w[raw_fifo_w_rp++];
    if (raw_fifo_w_rp > FJTAG_RAW_WSIZE) raw_fifo_w_rp-=FJTAG_RAW_WSIZE;
    if        (b1 == JTAG_RAW_SETCHN) { // set channel number
      raw_chn = b0;
      if (raw_chn>=JTAG_NCHANNELS) raw_chn=0; //illegal channel
      JTAG_push_raw (raw_chn);
    } else if (raw_chn) { // ignore commands until the JTAG channel number is specified
      if        ((b1 & 0xf0) == JTAG_RAW_SEND) { // send JTAG data
        JTAG_push_raw (jtag_send(raw_chn, (b1 >> 3) & 1, b1 & 7, (int) b0 ));
      } else if ((b1 & 0x80) == JTAG_RAW_WAIT) { // delay
        udelay(((b1 & 0x7f) <<8) + b0);
        JTAG_push_raw (0x80);
      } else switch (b1) {
        case JTAG_RAW_DEACT:
           set_pgm_mode (raw_chn, 0);
           JTAG_push_raw (0x0);
           break;
        case JTAG_RAW_ACT:
           set_pgm_mode (raw_chn, 1);
           JTAG_push_raw (0x0);
           break;
        case JTAG_RAW_PGMOFF:
           set_pgm (raw_chn, 0);
           JTAG_push_raw (read_done(raw_chn));
        case JTAG_RAW_PGMON:
           set_pgm (raw_chn, 1);
           JTAG_push_raw (0xf0);
           break;
        default:
           JTAG_push_raw (0xff);
        }
    } else { // make output always be 1 byte for 2 bytes input
       JTAG_push_raw (0xf0);
    } // end of if (raw_chn) /else
  } // while (raw_fifo_w_rp != (raw_fifo_w_wp & ~1)) 
  return 0; // will think of return value later
}

//returns 0 if all channels closed
// 
int JTAG_whatopen(void) {
  int i,r=0;
  for (i=0;i<JTAG_NCHANNELS;i++) r |= 1 << JTAG_channels[i].mode;
  return r;
}

//++++++++++++++++++++++++++++++++++++ open() ++++++++++++++++++++++++++++++++++++++++++++++++++++++

static int fpga_jtag_open(struct inode *inode, struct file *filp) {
   int i;
//   int res;
   int p = MINOR(inode->i_rdev);
   int chn= JTAG_channel(p);
   reg_intr_vect_rw_mask intr_mask;
   D(printk("fpga_open: minor=%x, channel=%x, buf=%p\r\n",p,chn,bitstream_data ));
   switch ( p ) {
     case FPGA_JTAG_RESET_MINOR : // same as RAW
       for (i=1; i<JTAG_NCHANNELS; i++) JTAG_channels[i].mode=JTAG_MODE_CLOSED;
       JTAG_channels[chn].mode=JTAG_MODE_RAW;
       JTAG_channels[chn].sizew =  FJTAG_RAW_WSIZE;
       JTAG_channels[chn].sizer =  FJTAG_RAW_RSIZE;
       JTAG_channels[chn].wp =  0;
       JTAG_channels[chn].rp =  0; // will read IDs if actually read
       raw_fifo_w_wp=0; 
       raw_fifo_w_rp=0;
       raw_fifo_r_wp=0;
       raw_fifo_r_rp=0;
       raw_chn=0;
       break;
     case FPGA_JTAG_MINOR :
       if ( JTAG_whatopen() & 0x7e) return -EACCES; // none of the channels could be open when opening this file
//       JTAG_channels[chn].mode  =  JTAG_MODE_PGM;
//       JTAG_channels[chn].dbuf  = &bitstream_data[0];
//       JTAG_channels[chn].sizew =  FJTAG_BUF_SIZE;
//       JTAG_channels[chn].sizer =  FJTAG_IDSIZE >> 3;
//       JTAG_channels[chn].wp =  0;
//       JTAG_channels[chn].rp =  0; // will read IDs if actually read
       fpga_state &= ~FPGA_STATE_LOADED;     // is it still used?
       fpga_state &= ~FPGA_STATE_SDRAM_INIT; // not needed
// disable camera interrupts here (while reprogramming FPGA could generate stray interrupts;
 /* Disable external interrupts.. */
       intr_mask = REG_RD(intr_vect, regi_irq, rw_mask);
       intr_mask.ext = 0;
       REG_WR(intr_vect, regi_irq, rw_mask, intr_mask); 
//     printk ("Camera interrupts disabled\r\n");
//       break;
// fall through
     case FPGA_SJTAG_MINOR :
     case FPGA_AJTAG_MINOR :
       if ( JTAG_whatopen() & 0x7e) return -EACCES; // none of the channels could be open when opening this file
       JTAG_channels[chn].mode  =  JTAG_MODE_PGM;
       JTAG_channels[chn].dbuf  = &bitstream_data[0];
       JTAG_channels[chn].sizew =  FJTAG_BUF_SIZE;
       JTAG_channels[chn].sizer =  FJTAG_IDSIZE >> 3;
       JTAG_channels[chn].wp =  0;
       JTAG_channels[chn].rp =  0; // will read IDs if actually read
       JTAG_channels[chn].bitsw = XC3S1200E_BITSIZE;  // bit size to be written
       JTAG_channels[chn].bitsr=  FJTAG_IDSIZE;
       JTAG_openChannel (chn); // configure channel access, reset JTAG and to RUN-TEST/IDLE state
       break;
     case FPGA_JTAG_BOUNDARY_MINOR :
     case FPGA_SJTAG_BOUNDARY_MINOR :
     case FPGA_AJTAG_BOUNDARY_MINOR :
       if ( JTAG_whatopen() & 0x46)  return -EACCES; // none of the channels could be open for program/id/raw when opening this file
       if ( JTAG_channels[chn].mode != JTAG_MODE_CLOSED) return -EACCES; // already open
       JTAG_channels[chn].mode  =  JTAG_MODE_BOUNDARY;
       JTAG_channels[chn].sizew =  (XC3S1200E_BOUNDARY_SIZE+7) >> 3;
       JTAG_channels[chn].sizer =  (XC3S1200E_BOUNDARY_SIZE+7) >> 3;
       JTAG_channels[chn].dbuf  = &bitstream_data[JTAG_channels[chn].sizew * chn];
       JTAG_channels[chn].wp =  0;
       JTAG_channels[chn].rp =  0; // will read IDs if actually read
       JTAG_channels[chn].bitsw = XC3S1200E_BOUNDARY_SIZE;  // bit size to be written
       JTAG_channels[chn].bitsr=  XC3S1200E_BOUNDARY_SIZE;
       JTAG_openChannel (chn); // configure channel access, reset JTAG and to RUN-TEST/IDLE state
       break;
     default: return -EINVAL;
   }
   D(printk("fpga_open: chn=%x, JTAG_channels[chn].sizew=%x, JTAG_channels[chn].sizer=%x\r\n", chn,JTAG_channels[chn].sizew, JTAG_channels[chn].sizer) );
   D(printk("fpga_open: chn=%x, JTAG_channels[chn].bitsw=%x, JTAG_channels[chn].bitsr=%x\r\n", chn,JTAG_channels[chn].bitsw, JTAG_channels[chn].bitsr) );
   JTAG_channels[chn].wdirty=0;
//   inode->i_size=fjtag_bytesize(p);
   inode->i_size=JTAG_channels[chn].sizer;
   minors[p]=p;
   filp->private_data = &minors[p];
   D(printk("fpga_open: inode->i_size=%x, chn=%x\r\n", (int) inode->i_size, chn) );
   return 0;
}

//++++++++++++++++++++++++++++++++++++ release() ++++++++++++++++++++++++++++++++++++++++++++++++++++++

static int fpga_jtag_release(struct inode *inode, struct file *filp) {
   int res=0;
   int p = MINOR(inode->i_rdev);
   int chn= JTAG_channel(p);
//   reg_intr_vect_rw_mask intr_mask;
  D(printk("fpga_jtag_release: p=%x,chn=%x,  wp=0x%x, rp=0x%x\r\n",p,chn, JTAG_channels[chn].wp, JTAG_channels[chn].rp));
   switch ( p ) {
     case FPGA_JTAG_RESET_MINOR : // same as RAW - do nothing, raw code should do it on it's own
       break;
     case FPGA_JTAG_MINOR :
     case FPGA_SJTAG_MINOR :
     case FPGA_AJTAG_MINOR :
       if (JTAG_channels[chn].wp > 0) { // anything written?
         res=JTAG_configure (chn, JTAG_channels[chn].dbuf, JTAG_channels[chn].wp);
         if ((res >=0) & (chn == JTAG_MAIN_FPGA)) fpga_state|=1; // Add 16-bit revision number here? (from file header)
       }
// reset initializing in any case:
       if (chn == JTAG_MAIN_FPGA) fpga_state &=~FPGA_STATE_INITIALIZED;
       JTAG_resetChannel (chn);

       break;
     case FPGA_JTAG_BOUNDARY_MINOR :
     case FPGA_SJTAG_BOUNDARY_MINOR :
     case FPGA_AJTAG_BOUNDARY_MINOR :
// "dirty"? Send to JTAG
       if (JTAG_channels[chn].wp >0) JTAG_EXTEST (chn, JTAG_channels[chn].dbuf, JTAG_channels[chn].bitsw); // size in bits
       JTAG_resetChannel (chn);
       break;
    default: return -EINVAL;
   }
   minors[p]=0;
   JTAG_channels[chn].mode=JTAG_MODE_CLOSED;
   D(printk("fpga_jtag_release:  done\r\n"));
   return (res<0)?res:0;
}


//++++++++++++++++++++++++++++++++++++ write() ++++++++++++++++++++++++++++++++++++++++++++++++++++++

//for boundary scan: writing before wp+1 will start EXTEST cycle (either rollover or lseek)
static ssize_t fpga_jtag_write(struct file * file, const char * buf, size_t count, loff_t *off) {
   int p = ((int *)file->private_data)[0];
   int chn= JTAG_channel(p);
   size_t size = JTAG_channels[chn].sizew;
  D(printk("fpga_jtag_write: p=%x,chn=%x, buf address=%lx count=%lx *offs=%lx, wp=%lx,size=0x%x\r\n",p,chn,(long) buf, (long) count, (long) *off, (long)JTAG_channels[chn].wp, (int) size));

   switch (p) {
     case FPGA_JTAG_RESET_MINOR : // same as RAW - do nothing, raw code should do it on it's own
       if (count > size) count= size;
       if ((raw_fifo_w_wp+count) > size) { // read tail, then roll over to the head to the total of count
         if (copy_from_user(&raw_fifo_w[raw_fifo_w_wp],buf,size-raw_fifo_w_wp)) return -EFAULT; // read tail
         if (copy_from_user(&raw_fifo_w[0],&buf[size-raw_fifo_w_wp],count+raw_fifo_w_wp-size)) return -EFAULT; // read head
       } else {
         if (copy_from_user(&raw_fifo_w[raw_fifo_w_wp],buf,count)) return -EFAULT; // read count
       }
       raw_fifo_w_wp+=count;
       if (raw_fifo_w_wp > size) raw_fifo_w_wp -= size;
       JTAG_process_raw(); // send all the received data to JTAG - will cause read fifo to get ~1/2 of the number of bytes written
       break;
     case FPGA_JTAG_MINOR  :
     case FPGA_SJTAG_MINOR :
     case FPGA_AJTAG_MINOR : // read configuration data to buffer
       if (*off > size) return -EFAULT;
       if ((*off + count) > size) count= (size - *off);
       if (copy_from_user(&(JTAG_channels[chn].dbuf[*off]),buf,count)) return -EFAULT;
       *off+=count;
       if (*off > JTAG_channels[chn].wp) JTAG_channels[chn].wp= *off;
       break;
     case FPGA_JTAG_BOUNDARY_MINOR :
     case FPGA_SJTAG_BOUNDARY_MINOR :
     case FPGA_AJTAG_BOUNDARY_MINOR :
       if (*off > size) return -EFAULT;
       if ((*off + count) > size) count= (size - *off);
//       if ((*off < JTAG_channels[chn].wp) || (JTAG_channels[chn].mode!=JTAG_MODE_EXTEST)) {
       if (*off < JTAG_channels[chn].wp) {
         JTAG_EXTEST (chn, JTAG_channels[chn].dbuf, JTAG_channels[chn].bitsw); // writing "before" causes EXTEST to fill in boundary scan register
         JTAG_channels[chn].wdirty=0;
       }
       if (copy_from_user(&(JTAG_channels[chn].dbuf[*off]),buf,count)) return -EFAULT;
       *off+=count;
       JTAG_channels[chn].wp= *off; // before rolling over
       if (*off >= size) {
         *off=0; // roll over
       }
       JTAG_channels[chn].mode=JTAG_MODE_EXTEST; //should write the last byte before reading - or buffer data will be just lost
       JTAG_channels[chn].wdirty=1;
       break;
     default:               return -EINVAL;
   }
 D(printk("fpga_jtag_write end: p=%x,chn=%x, buf address=%lx count=%lx *offs=%lx, wp=%lx,size=0x%x\r\n",p,chn,(long) buf, (long) count, (long) *off, (long)JTAG_channels[chn].wp, (int) size));
   return count;
}

//++++++++++++++++++++++++++++++++++++ read() ++++++++++++++++++++++++++++++++++++++++++++++++++++++

ssize_t fpga_jtag_read(struct file * file, char * buf, size_t count, loff_t *off) {
   int p = ((int *)file->private_data)[0];
   int chn= JTAG_channel(p);
   size_t size = JTAG_channels[chn].sizer;
   int size_av;  // available data
 //  D(printk("fpga_jtag_read from 0x%x, count=0x%x, size=0x%x\n", (int) *off, (int) count, (int) size));
 D(printk("fpga_jtag_read: p=%x,chn=%x, buf address=%lx count=%lx *offs=%lx, rp=%lx,size=0x%x\r\n",p,chn,(long) buf, (long) count, (long) *off, (long)JTAG_channels[chn].rp, (int) size));
   switch (p) {
     case FPGA_JTAG_RESET_MINOR : // same as RAW - do nothing, raw code should do it on it's own
       size_av=(raw_fifo_r_wp >= raw_fifo_r_rp)?(raw_fifo_r_wp - raw_fifo_r_rp):(size+raw_fifo_r_wp - raw_fifo_r_rp);
       if (count > size_av) count= size_av;
       if ((raw_fifo_r_rp+count) > size) { // read tail, then roll over to the head to the total of count
         if (copy_to_user(buf, &raw_fifo_r[raw_fifo_r_rp],size-raw_fifo_r_rp)) return -EFAULT; // read tail
         if (copy_to_user(&buf[size-raw_fifo_r_rp],&raw_fifo_r[0],count+raw_fifo_r_rp-size)) return -EFAULT; // read head
       } else {
         if (copy_to_user(buf,&raw_fifo_w[raw_fifo_w_wp],count)) return -EFAULT; // read count
       }
       raw_fifo_r_rp+=count;
       if (raw_fifo_r_rp > size) raw_fifo_r_rp -= size;
       break;
     case FPGA_JTAG_MINOR  :
     case FPGA_SJTAG_MINOR :
     case FPGA_AJTAG_MINOR : // read configuration data to buffer
       if ((JTAG_channels[chn].wp==0) && (JTAG_channels[chn].rp==0)) { // starting from read - get ID
         JTAG_channels[chn].mode=JTAG_MODE_RDID;
         JTAG_readID (chn, JTAG_channels[chn].dbuf);
       }
       if (*off > size) return -EFAULT;
       if ((*off + count) > size) count= (size - *off);
D(printk("fpga_jtag_read_01: p=%x,chn=%x, buf address=%lx count=%lx *offs=%lx, rp=%lx,size=0x%x\r\n",p,chn,(long) buf, (long) count, (long) *off, (long)JTAG_channels[chn].rp, (int) size)); // D(printk("count= 0x%x, pos= 0x%x\n", (int) count, (int)*off));

       if (copy_to_user(buf,&(JTAG_channels[chn].dbuf[*off]),count)) return -EFAULT;
       *off+=count;
       JTAG_channels[chn].rp= *off;
       break;
     case FPGA_JTAG_BOUNDARY_MINOR :
     case FPGA_SJTAG_BOUNDARY_MINOR :
     case FPGA_AJTAG_BOUNDARY_MINOR :
       if ((JTAG_channels[chn].mode==JTAG_MODE_EXTEST) && (JTAG_channels[chn].wdirty || (*off < JTAG_channels[chn].rp))) {
         JTAG_EXTEST (chn, JTAG_channels[chn].dbuf, JTAG_channels[chn].bitsr); // writing last byte causes EXTEST to fill in boundary scan register
         JTAG_channels[chn].wdirty=0;
       }
// (re)-read capture pins if it was a roll-over or the first access after open
       if ((JTAG_channels[chn].mode!=JTAG_MODE_EXTEST) && ((*off < JTAG_channels[chn].rp) || (JTAG_channels[chn].mode==JTAG_MODE_BOUNDARY))) {
         JTAG_CAPTURE (chn, JTAG_channels[chn].dbuf, JTAG_channels[chn].bitsr);
       }
       if (*off > size) return -EFAULT;
       if ((*off + count) > size) count= (size - *off);
D(printk("fpga_jtag_read_01: p=%x,chn=%x, buf address=%lx count=%lx *offs=%lx, rp=%lx,size=0x%x\r\n",p,chn,(long) buf, (long) count, (long) *off, (long)JTAG_channels[chn].rp, (int) size)); // D(printk("count= 0x%x, pos= 0x%x\n", (int) count, (int)*off));
//       if (*off < JTAG_channels[chn].rp) {
//         JTAG_EXTEST (chn, JTAG_channels[chn].dbuf, JTAG_channels[chn].bitsw); // writing last byte causes EXTEST to fill in boundary scan register
//         JTAG_channels[chn].wdirty=0;
//       }
       if (copy_to_user(buf,&(JTAG_channels[chn].dbuf[*off]),count)) return -EFAULT;
       *off+=count;
       JTAG_channels[chn].rp= *off; // before rolling over
       if (*off >= size) {
         *off=0; // roll over
       }
       if (JTAG_channels[chn].mode == JTAG_MODE_BOUNDARY) JTAG_channels[chn].mode=JTAG_MODE_SAMPLE; //should write the last byte before reading - or buffer data will be just lost
       break;
     default:               return -EINVAL;
   }
D(printk("fpga_jtag_read_end: p=%x,chn=%x, buf address=%lx count=%lx *offs=%lx, rp=%lx,size=0x%x, mode=%x\r\n",p,chn,(long) buf, (long) count, (long) *off, (long)JTAG_channels[chn].rp, (int) size, JTAG_channels[chn].mode)); // D(printk("count= 0x%x, pos= 0x%x\n", (int) count, (int)*off));
  return count;
}

//++++++++++++++++++++++++++++++++++++ lseek() ++++++++++++++++++++++++++++++++++++++++++++++++++++++

static loff_t  fpga_jtag_lseek(struct file * file, loff_t offset, int orig) {
/*
 *  orig 0: position from begning of eeprom
 *  orig 1: relative from current position
 *  orig 2: position from last eeprom address
 */
   int p = ((int *)file->private_data)[0];
   int chn= JTAG_channel(p);
   size_t size;
     if (chn==JTAG_RAW) {
       size=raw_fifo_r_wp-raw_fifo_r_rp;
       if (size<0) size+=FJTAG_RAW_RSIZE;
     } else   size = JTAG_channels[chn].sizew;
   if (JTAG_channels[chn].mode == JTAG_MODE_RDID) size = JTAG_channels[chn].sizer;
   D(printk("fpga_jtag_lseek, fsize= 0x%x\n", (int) size));
        switch (orig) {
        case 0:
                file->f_pos = offset;
                break;
        case 1:
                file->f_pos += offset;
                break;
        case 2:
                file->f_pos = size + offset;
                break;
        default:
                return -EINVAL;
        }
        /* truncate position */
        if (file->f_pos < 0) {
                file->f_pos = 0;
                return (-EOVERFLOW);
        }

        if (file->f_pos > size) {
                file->f_pos = size;
                return (-EOVERFLOW);
        }
   D(printk("fpga_jtag_lseek, file->f_pos= 0x%x\n", (int) file->f_pos));
        return (file->f_pos);
}

//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

// Initialize GPIOs of the CPU to access JPTAG/programming of the main FPGA
void initPortC(void) {
// connect 8 lower bits of port C to GPIO, disconnect from IOP
    unsigned long tmp;
    reg_pinmux_rw_pc_iop    pinmux_c_iop;
    reg_pinmux_rw_pc_gio    pinmux_c_gio;
    reg_gio_rw_pc_oe        pc_oe;

    pinmux_c_iop= REG_RD(pinmux, regi_pinmux, rw_pc_iop);
    tmp = REG_TYPE_CONV(unsigned long, reg_pinmux_rw_pc_iop, pinmux_c_iop);
    tmp &= ~0xff;
    pinmux_c_iop = REG_TYPE_CONV(reg_pinmux_rw_pc_iop, unsigned long, tmp);
    REG_WR(pinmux, regi_pinmux, rw_pc_iop, pinmux_c_iop);

    pinmux_c_gio= REG_RD(pinmux, regi_pinmux, rw_pc_gio);
    tmp = REG_TYPE_CONV(unsigned long, reg_pinmux_rw_pc_gio, pinmux_c_gio);
    tmp |= 0xff;
    pinmux_c_gio = REG_TYPE_CONV(reg_pinmux_rw_pc_gio, unsigned long, tmp);
    REG_WR(pinmux, regi_pinmux, rw_pc_gio, pinmux_c_gio);

// now set data of port C pins (static pc_dout)
    pc_dout = REG_RD(gio, regi_gio, rw_pc_dout);
    pc_dout.data &= ~0xff;
    pc_dout.data |= PC_DOUT_INITIAL;
    REG_WR(gio, regi_gio, rw_pc_dout, pc_dout);

// now set directions of port C pins
    pc_oe = REG_RD(gio, regi_gio, rw_pc_oe);
    pc_oe.oe &= ~( (1 << FPGAJTAG_TDO_BIT) |
                   (1 << FPGAJTAG_DONE_BIT) |
                   (1 << FPGAJTAG_RSTBTN_BIT)); 
    pc_oe.oe |=  ( (1 << FPGAJTAG_TDI_BIT) |
                   (1 << FPGAJTAG_TMS_BIT) |
                   (1 << FPGAJTAG_TCK_BIT) |
                   (1 << FPGAJTAG_PGM_BIT)); 
    REG_WR(gio, regi_gio, rw_pc_oe, pc_oe);
}

// set FPGA in programming/JTAG mode (only for sensor board)
// NOP for the main board FPGA configuration
void set_pgm_mode (int chn, int en) {
D(printk ("set_pgm_mode (%d,%d)\n",chn,en));

    switch (chn) {
    case JTAG_SENSOR_FPGA:
      port_csp0_addr[X313_WA_SENSFPGA] = (en ? (3 << SFPGA_PGMEN_BIT): (SFPGA_RD_SENSPGMPIN | (2 << SFPGA_PGMEN_BIT))) | (2  << SFPGA_TCK_BIT); // turn off TCK (if not turned off already)
      break;
    }
   udelay (2);
}

void set_pgm (int chn, int pgmon) {
D(printk ("set_pgm (%d,%d)\n",chn,pgmon));
    switch (chn) {
    case JTAG_MAIN_FPGA:
      if (pgmon) pc_dout.data  &= ~0x80; // set PGM low (active)
      else pc_dout.data  |= 0x80;        // set PGM high (inactive)
      REG_WR(gio, regi_gio, rw_pc_dout, pc_dout); // extend low?
      break;
     case JTAG_SENSOR_FPGA:
      port_csp0_addr[X313_WA_SENSFPGA] = (2 | (pgmon & 1)) << SFPGA_PROG_BIT;
      break;
     case JTAG_AUX_FPGA:
      break;
    }
   udelay (2);
}


int read_done (int chn) {
   switch (chn) {
    case JTAG_MAIN_FPGA:
      return ((((REG_RD(gio, regi_gio, r_pc_din)).data & 0x20)==0) ? 0 : 1 ); 
    case JTAG_SENSOR_FPGA:
      port_csp0_addr[X313_WA_SENSFPGA] = SFPGA_RD_DONE;
      udelay (1); 
      return (port_csp0_addr[X313__RA__SENSFPGA] >> SFPGA_RD_BIT) & 1 ;
    case JTAG_AUX_FPGA:
      return 0;
   }
   return 0; // just in case
}

//  send 1..8 bits through JTAG 
int jtag_send (int chn, int tms, int len, int d) {
   int i; //,m;
   int r=0;
   int d0;
   i = len & 7;
   if (i==0) i=8;
   d &= 0xff;
   d0=d;
  D( printk("jtag_send(0x%x, 0x%x, 0x%x, 0x%x)\r\n", chn, tms,len,d));
   switch (chn) {
    case JTAG_MAIN_FPGA:

       pc_dout.data &= ~0x0e;
       pc_dout.data |= (tms & 1) << FPGAJTAG_TMS_BIT;
       for (;i>0;i--){
         r= (r<<1)+ ((REG_RD(gio, regi_gio, r_pc_din)).data & 1); // read TDO before TCK pulse
         pc_dout.data = (pc_dout.data & ~0x0a) | (((d<<=1)>>7) & 2);
         REG_WR(gio, regi_gio, rw_pc_dout, pc_dout);
         pc_dout.data |= (1 << FPGAJTAG_TCK_BIT);
         REG_WR(gio, regi_gio, rw_pc_dout, pc_dout);
         pc_dout.data &= ~(1 << FPGAJTAG_TCK_BIT);
         REG_WR(gio, regi_gio, rw_pc_dout, pc_dout);
       }
       break;
    case JTAG_SENSOR_FPGA:
       port_csp0_addr[X313_WA_SENSFPGA] = SFPGA_RD_TDO;
       udelay (1); // wait MUX
       for (;i>0;i--){
   port_csp0_addr[X313_WA_SENSFPGA] = (2  << SFPGA_TCK_BIT); // TCK=0 - just a delay
           port_csp0_addr[X313_WA_SENSFPGA] = ((2 | (tms & 1)) << SFPGA_TMS_BIT) |
                                              (((((d<<=1)>>8) & 1) | 2) << SFPGA_TDI_BIT) |
                                              (2  << SFPGA_TCK_BIT) ;
   port_csp0_addr[X313_WA_SENSFPGA] = (2  << SFPGA_TCK_BIT); // TCK=0 - just a delay
         port_csp0_addr[X313_WA_SENSFPGA] = (3  << SFPGA_TCK_BIT); // TCK=1
         r= (r<<1)+ ((port_csp0_addr[X313__RA__SENSFPGA] >> SFPGA_RD_BIT) & 1); // read TDO before TCK pulse
   port_csp0_addr[X313_WA_SENSFPGA] = (2  << SFPGA_TCK_BIT); // TCK=0 - just a delay

       }
       port_csp0_addr[X313_WA_SENSFPGA] = (2  << SFPGA_TCK_BIT); // TCK=0
       break;
    case JTAG_AUX_FPGA:
      break;
   }
   return r;
}

//====================================
//         port_csp0_addr[X313_WA_SENSFPGA] = 0; // nop
// write data data bytes from buffer, read data, optionally compare/abort
// return: 0- OK, !=0 - readback mismatch error
// modified so it reads data in-place of the written one
// send/receive bits, raising TMS during the last one (if last==1). If number of bits are not multiple of 8, lower bits of the last byte will not be used.

int jtag_write_bits (int chn,
                     unsigned char *buf, // data to write
                     int len,            // number of bytes to write
                     int check,          // compare readback data with previously written, abort on mismatch
                     int last,           // output last bit with TMS=1
                     int prev[2])      // if null - don't use
{
   int i,j;
   int r=0;
   int d,d0;
  D( printk("jtag_write_bits(0x%x, 0x%x, 0x%x, 0x%x, 0x%x)\r\n", (int) chn, (int) buf, len, check, last););

   switch (chn) {
    case JTAG_MAIN_FPGA: //TODO: save some cycles like for FPGA_SJTAG_MINOR

       for (i=0; len>0;i++) {
         pc_dout.data &= ~0x0e;
         d0=(d=buf[i]);
         for (j=0;j<8;j++) {
//D(printk("i=%x, j=%x, len=%x, d=%x  ",i,j,len,d));
           if (len>0) {
             r= (r<<1)+ ((REG_RD(gio, regi_gio, r_pc_din)).data & 1);
             if ((len==1) && last) pc_dout.data = (pc_dout.data & ~0x0a) | (((d<<=1)>>7) & 2) | (1 << FPGAJTAG_TMS_BIT);
             else                  pc_dout.data = (pc_dout.data & ~0x0a) | (((d<<=1)>>7) & 2);
             REG_WR(gio, regi_gio, rw_pc_dout, pc_dout);
             pc_dout.data |= (1 << FPGAJTAG_TCK_BIT);
             REG_WR(gio, regi_gio, rw_pc_dout, pc_dout);
             pc_dout.data &= ~(1 << FPGAJTAG_TCK_BIT);
             REG_WR(gio, regi_gio, rw_pc_dout, pc_dout);
           } else r= (r<<1);
           len--;
//D(printk(", r=%x\r\n",r));
         }
         buf[i]=r; // read back in-place
         if (check && ((r ^ (prev[1] >> 24)) & 0xff)) {
           return -((r & 0xff) | ((i+1) << 8)); //readback mismatch
         }
         if (prev) {
//         prev64= (prev64<<8) | ((prev32>>24) & 0xff);
//         prev32= (prev32<<8) | (d0 & 0xff);
           prev[1]= (prev[1]<<8) | ((prev[0]>>24) & 0xff);
           prev[0]= (prev[0]<<8) | (d0 & 0xff);
         }
       }
       break;
    case JTAG_SENSOR_FPGA:
       port_csp0_addr[X313_WA_SENSFPGA] = SFPGA_RD_TDO; // just in case, it should be in that mode whan calling jtag_write_bits()
       udelay (1); // wait MUX
       for (i=0; len>0;i++) {
         d0=(d=buf[i]);
         for (j=0;j<8;j++) {
   port_csp0_addr[X313_WA_SENSFPGA] = (2  << SFPGA_TCK_BIT); // TCK=0 - just a delay
           if (len>0) {
             if ((len==1) && last) port_csp0_addr[X313_WA_SENSFPGA] = 
                                              (3 << SFPGA_TMS_BIT) |
                                              (((((d<<=1)>>8) & 1) | 2) << SFPGA_TDI_BIT) |
                                              (2 << SFPGA_TMS_BIT) |
                                              (2 << SFPGA_TCK_BIT) ; 

             else port_csp0_addr[X313_WA_SENSFPGA] =
                                              (((((d<<=1)>>8) & 1) | 2) << SFPGA_TDI_BIT) |
                                              (2 << SFPGA_TMS_BIT) |
                                              (2 << SFPGA_TCK_BIT) ; 
   port_csp0_addr[X313_WA_SENSFPGA] = (2  << SFPGA_TCK_BIT); // TCK=0 - just a delay
             port_csp0_addr[X313_WA_SENSFPGA] = (3 << SFPGA_TCK_BIT); // TCK=1
// add delays here if long cable?
             r= ((r<<1)+ ((port_csp0_addr[X313__RA__SENSFPGA] >> SFPGA_RD_BIT) & 1)); // read TDO before TCK pulse
   port_csp0_addr[X313_WA_SENSFPGA] = (2  << SFPGA_TCK_BIT); // TCK=0 - just a delay
           } else r= (r<<1);
           len--;
         }
         buf[i]=r; // read back in-place
         if (check && ((r ^ (prev[1]>>24)) & 0xff)) {
           return -((r & 0xff) | ((i+1) << 8)); //readback mismatch
         }
         if (prev) {
//         prev64= (prev64<<8) | ((prev32>>24) & 0xff);
//         prev32= (prev32<<8) | (d0 & 0xff);
           prev[1]= (prev[1]<<8) | ((prev[0]>>24) & 0xff);
           prev[0]= (prev[0]<<8) | (d0 & 0xff);
         }

       }
     port_csp0_addr[X313_WA_SENSFPGA] = (2  << SFPGA_TCK_BIT); // TCK=0
     break;
    case JTAG_AUX_FPGA:
      break;

  }
  return 0;
}


int JTAG_configure (int chn, unsigned char * buf, int len) {
  int datastart, i, j ,r;
//static int prev32;
//static int prev64;
  int prev[2];
#ifdef JTAG_DISABLE_IRQ
  unsigned long flags;
#endif
  const unsigned char sync[]={0xff,0xff,0xff,0xff,0xaa,0x99,0x55,0x66};
  int skipvfy=8;

  D(printk("JTAG_configure: chn=%x,  wp=0x%x, rp=0x%x, len=0x%x\r\n",chn, JTAG_channels[chn].wp, JTAG_channels[chn].rp, len));

// all the programming goes here...
// find sync:
  
  datastart=-1;
  for (i=0;i<(FJTAG_MAX_HEAD-8);i++) {
    j=0;
    while ((j<8) && (buf[i+j]==sync[j])) j++;
    if (j==8) {
      datastart=i;
      break;
    }
  }
  if (datastart<0) {
    printk("Bitstream not found - bad file\r\n");
    return -EFAULT;
  }
// check for right bitstream length
  if ((len-datastart)!=(XC3S1200E_BITSIZE>>3)) {
    printk("Wrong bitstream size - XC3S1200E has bitstream of %d bits (%d bytes)\n",XC3S1200E_BITSIZE,XC3S1200E_BITSIZE>>3);
    printk ("header size - %d, data size - %d\r\n",datastart, len-datastart);
    return -EFAULT;
  }
// enable programmimg mode (nop for the 10353 FPGA)
   set_pgm_mode(chn, 1);
// reset device  
   set_pgm (chn, 1);
   udelay (1000); // needed?
   set_pgm (chn, 0);
// wait INIT over - no init connected, just wait >2ms
   udelay (2500);
//*************************** NOW DISABLE INTERRUPS FOR THE WHOLE PROGRAMMING CYCLE ***********************
  D( udelay (100000);printk("JTAG_configure(): IRQ off!\r\n"); udelay (100000););
#ifdef JTAG_DISABLE_IRQ
   local_irq_save(flags);
   //local_irq_disable();
#endif
// prepare JTAG
  jtag_send(chn, 1, 5, 0   ); //step 1 - set Test-Logic-Reset state
  jtag_send(chn, 0, 1, 0   ); //step 2 - set Run-Test-Idle state
  jtag_send(chn, 1, 2, 0   ); //step 3 - set SELECT-IR state
  jtag_send(chn, 0, 2, 0   ); //step 4 - set SHIFT-IR state
  jtag_send(chn, 0, 5, 0xa0); //step 5 - start of CFG_IN  ***NOW 6 bits ***
  jtag_send(chn, 1, 1, 0   ); //step 6 - finish CFG_IN
  jtag_send(chn, 1, 2, 0   ); //step 7 - set SELECT-DR state
  jtag_send(chn, 0, 2, 0   ); //step 8 - set SHIFT-DR state
// write data (first 8 bytes - just fill the buffer, no readback comparison)
  jtag_write_bits (chn, 
                   &buf[datastart], // data to write
                   skipvfy << 3,               // number of bytes to write
                   0,                          // compare readback data with previously written, abort on mismatch
                   0,                          // do not raise TMS at last bit
                   prev);                      // 64 bits storage to verify configuration transmission

  if ((r=jtag_write_bits (chn, 
                          &buf[datastart+skipvfy],
//                          (buf8i-(datastart+skipvfy)) << 3,
                          (len-(datastart+skipvfy)) << 3,
                          1,
                          1, prev))<0) {
     r= -r;
     i= (r>>8) -1 + (datastart+skipvfy);
     r &= 0xff;
#ifdef JTAG_DISABLE_IRQ
     local_irq_restore(flags);
#endif
     set_pgm (chn, 1);
     set_pgm (chn, 0);
// disable programmimg mode (nop for the 10353 FPGA)
     set_pgm_mode(chn, 0);
     printk ("**** Configuration failed at byte # %d (%x)****\n", (i-datastart),(i-datastart));
     printk ("**** r= %x, prev64=%x prev32=%x****\n", r,prev[1], prev[0]);
     return -EFAULT; 
  }
  jtag_send(chn, 1, 1, 0   ); //step 11 - set UPDATE-DR state
  jtag_send(chn, 1, 2, 0   ); //step 12 - set SELECT-IR state
  jtag_send(chn, 0, 2, 0   ); //step 13 - set SHIFT-IR state
  jtag_send(chn, 0, 5, 0x30); //step 14 - start of JSTART  ***NOW 6 bits ***
  jtag_send(chn, 1, 1, 0   ); //step 15 - finish JSTART
  jtag_send(chn, 1, 2, 0   ); //step 16 - set SELECT-DR state
  jtag_send(chn, 0, 0, 0   ); //step 17 - set SHIFT-DR , clock startup
  jtag_send(chn, 0, 0, 0   ); //step 17a - (total >=12 clocks)
  jtag_send(chn, 1, 2, 0   ); //step 18 - set UPDATE-DR state
  jtag_send(chn, 0, 1, 0   ); //step 19 - set Run-Test-Idle state
  jtag_send(chn, 0, 0, 0   ); //step 19a - only here starts the sequence - adding 17b does not help (5 - sets done, 6 - releases outputs, 7 - releases reset)
  jtag_send(chn, 0, 0, 0   ); //step 19b - one more?
  // ready or not - device should start now
#ifdef JTAG_DISABLE_IRQ
  local_irq_restore(flags);
#endif
//*************************** END OF NO INTERRUPS ***********************
  r=read_done(chn);
// disable programmimg mode (nop for the 10353 FPGA)
  set_pgm_mode(chn, 0);

  if (r==0) {
    printk("*** FPGA did not start after configuration ***\r\n");
    return -EFAULT; 
  }

  D( udelay (100000);printk("\nJTAG_configure() OK!\r\n"));
  return 0;
} //int JTAG_configure


//=============================
//
// enable access to JTAG pins. For sensor FPGA that is not possible w/o deprogramming the chip
// leaves in Run-Test-Idle state
int JTAG_openChannel (int chn)  {
D(printk ("JTAG_openChannel (%d)\n",chn));
// enable programmimg mode (nop for the 10353 FPGA)
     set_pgm_mode(chn, 1);
// for shared JTAG/data bus we need to de-program the chip to be able to read JTAG :-(
     switch (chn) {
      case JTAG_SENSOR_FPGA:
// reset device  
       set_pgm (chn, 1);
       set_pgm (chn, 0);
// wait INIT over - no init connected, just wait >2ms
       udelay (2500);
      break;
     }
     jtag_send(chn, 1, 5, 0   ); // set Test-Logic-Reset state
     jtag_send(chn, 0, 1, 0   ); // set Run-Test-Idle state
} // int JTAG_openChannel (int chn)
//
int JTAG_resetChannel (int chn)  {
D(printk ("JTAG_resetChannel (%d)\n",chn));
     jtag_send(chn, 1, 5, 0   ); // set Test-Logic-Reset state
// disable programmimg mode (nop for the 10353 FPGA)
     set_pgm_mode(chn, 0); // only for sensor FPGA
} // int JTAG_resetChannel (int chn)

int JTAG_readID (int chn, unsigned char * buf)  {
  int i;
  unsigned long d1,d2=0;
  unsigned long * dp;
#ifdef JTAG_DISABLE_IRQ
  unsigned long flags;
#endif

// read dev id, user id
//*************************** NOW DISABLE INTERRUPS FOR THE WHOLE JTAG SEQUENCE ***********************
#ifdef JTAG_DISABLE_IRQ
     local_irq_save(flags);
     //local_irq_disable();
#endif
// prepare JTAG
     jtag_send(chn, 1, 5, 0   ); //step 1 - set Test-Logic-Reset state
     jtag_send(chn, 0, 1, 0   ); //step 2 - set Run-Test-Idle state
     jtag_send(chn, 1, 2, 0   ); //step 3 - set SELECT-IR state
     jtag_send(chn, 0, 2, 0   ); //step 4 - set SHIFT-IR state
     jtag_send(chn, 0, 5, 0x90); //step 5 - start of IDCODE
     jtag_send(chn, 1, 1, 0   ); //step 6 - finish IDCODE
     jtag_send(chn, 1, 2, 0   ); //step 7 - set SELECT-DR state
     jtag_send(chn, 0, 2, 0   ); //step 8 - set CAPTURE-DR state
     jtag_write_bits (chn, 
                      &buf[0], // data to write
                      32, // number of bits to write/read
                      0,                          // don't compare readback data with previously written
                      1, 0) ;                        // raise TMS at last bit
     jtag_send(chn, 1, 5, 0   ); //reset state machine to Test-Logic-Reset state
     jtag_send(chn, 0, 1, 0   ); //step 2 - set Run-Test-Idle state
     jtag_send(chn, 1, 2, 0   ); //step 3 - set SELECT-IR state
     jtag_send(chn, 0, 2, 0   ); //step 4 - set SHIFT-IR state
     jtag_send(chn, 0, 5, 0x10); //step 5 - start of USERCODE
     jtag_send(chn, 1, 1, 0   ); //step 6 - finish USERCODE
     jtag_send(chn, 1, 2, 0   ); //step 7 - set SELECT-DR state
     jtag_send(chn, 0, 2, 0   ); //step 8 - set CAPTURE-DR state
     jtag_write_bits (chn,
                      &buf[4], // data to write
                      32, // number of bits to write/read
                      0,                          // don't compare readback data with previously written
                      1,0) ;                      // raise TMS at last bit
     jtag_send(chn,1, 5, 0   ); //reset state machine to Test-Logic-Reset state
#ifdef JTAG_DISABLE_IRQ
     local_irq_restore(flags);
#endif
//*************************** END OF NO INTERRUPS ***********************
// swap all bits in ID and user fields
     dp = (unsigned long *) &buf[0];
     d1= *dp;
     for (i=0;i<32;i++){
        d2 = (d2 << 1) | (d1 & 1);
        d1 >>= 1;
     }
     *dp=d2;
     dp = (unsigned long *) &buf[4];
     d1= *dp;
     for (i=0;i<32;i++){
        d2 = (d2 << 1) | (d1 & 1);
        d1 >>= 1;
     }
     *dp=d2;
     D(for (i=0; i<8;i++) {printk("%3x ",(int) buf[i]); if ((i & 0xf) == 0xf) printk ("\n");} ); 
     data_modified=0; //*************************************************
     return 0;
} // int JTAG_readID (int chn, unsigned char * buf)

/*
 * capture all pins w/o changing functionality
 * assuming Run-Test-Idle/UPDATE-DR leaving UPDATE-DR
 */

int JTAG_CAPTURE (int chn, unsigned char * buf, int len) {
//int i; // only in debug
#ifdef JTAG_DISABLE_IRQ
  unsigned long flags;
#endif
D(printk("buf=%p\n",buf));
//*************************** NOW DISABLE INTERRUPS FOR THE WHOLE JTAG SEQUENCE ***********************
#ifdef JTAG_DISABLE_IRQ
     local_irq_save(flags);
     //local_irq_disable();
#endif
// prepare JTAG
//     jtag_send(chn, 1, 5, 0   ); //step 1 - set Test-Logic-Reset state
//     jtag_send(chn, 0, 1, 0   ); //step 2 - set Run-Test-Idle state
     jtag_send(chn, 1, 2, 0   ); //step 3 - set SELECT-IR state
     jtag_send(chn, 0, 2, 0   ); //step 4 - set SHIFT-IR state
     jtag_send(chn, 0, 5, 0x80); //step 5 - start of SAMPLE (which bit goes first???)
     jtag_send(chn, 1, 1, 0   ); //step 6 - finish SAMPLE
     jtag_send(chn, 1, 2, 0   ); //step 7 - set SELECT-DR state
     jtag_send(chn, 0, 2, 0   ); //step 8 - set CAPTURE-DR state
     jtag_write_bits (chn, 
                      buf, // data to write
                      len, // number of bits to read
                      0,   // don't compare readback data with previously written
                      1,0) ; // raise TMS at last bit
//     D(printk ("\n"); for (i=0; i<((len+7)>>3) ;i++) {printk("%3x ",(int) buf[i]); if ((i & 0xf) == 0xf) printk ("\n");}printk ("\n"); ); 
//     D(printk ("\n"); for (i=0; i<((len+7)>>3) ;i++) {printk("%3x ",(int) buf[i]); if ((i & 0xf) == 0xf) printk ("\n");}printk ("\n"); ); 
     jtag_send(chn, 1, 1, 0   ); //step 9 - set UPDATE-DR state
//     D(printk ("\n"); for (i=0; i<((len+7)>>3) ;i++) {printk("%3x ",(int) buf[i]); if ((i & 0xf) == 0xf) printk ("\n");}printk ("\n"); ); 
//     jtag_send(chn,1, 5, 0   ); //reset state machine to Test-Logic-Reset state
#ifdef JTAG_DISABLE_IRQ
     local_irq_restore(flags);
#endif
//*************************** END OF NO INTERRUPS ***********************
     D(printk ("\n"); for (i=0; i<((len+7)>>3) ;i++) {printk("%3x ",(int) buf[i]); if ((i & 0xf) == 0xf) printk ("\n");}printk ("\n"); ); 
     data_modified=0;
     return 0;

} // JTAG_CAPTURE (int chn, unsigned char * buf, int len) {


/*
 * write new boundary registers (len should match BS register length), read pins in-place
 * TAP controller is supposed to be in "UPDATE-DR" state (or RUN-TEST/IDLE after just opening this mode)
 * TAP controller will be left in the same "UPDATE-DR" after the command
 */
int JTAG_EXTEST (int chn, unsigned char * buf, int len) {
#ifdef JTAG_DISABLE_IRQ
  unsigned long flags;
#endif
//int i; // only in debug
#ifdef JTAG_DISABLE_IRQ
     local_irq_save(flags);
     //local_irq_disable();
#endif
D(printk("EXTEST: buf=%p, len=0x%x\n",buf,len));

//     jtag_send(chn, 1, 5, 0   ); //step 1 - set Test-Logic-Reset state
//     jtag_send(chn, 0, 1, 0   ); //step 2 - set Run-Test-Idle state
     jtag_send(chn, 1, 2, 0   ); //step 3 - set SELECT-IR state
     jtag_send(chn, 0, 2, 0   ); //step 4 - set SHIFT-IR state
     jtag_send(chn, 0, 5, 0xf0); //step 5 - start of EXTEST
     jtag_send(chn, 1, 1, 0   ); //step 6 - finish EXTEST
     jtag_send(chn, 1, 2, 0   ); //step 7 - set SELECT-DR state
     jtag_send(chn, 0, 2, 0   ); //step 8 - set CAPTURE-DR state

     jtag_write_bits  (chn, 
                       buf,
                       len, // number of bits to write
                       0,                         // don't compare readback data with previously written
                       1,0);                        // raise TMS at last bit
    jtag_send(chn, 1, 1, 0   ); //step 9 - set UPDATE-DR state
#ifdef JTAG_DISABLE_IRQ
     local_irq_restore(flags);
#endif
     D(printk ("\n"); for (i=0; i<((len+7)>>3) ;i++) {printk("%3x ",(int) buf[i]); if ((i & 0xf) == 0xf) printk ("\n");}printk ("\n"); ); 

    return 0;
} //int JTAG_EXTEST (int chn, unsigned char * buf, int len)

static int __init fpga_jtag_init(void) {
   int i,res;
   res = register_chrdev(FPGA_JTAG_MAJOR, fpga_jtag_name, &fpga_jtag_fops);
   if(res < 0) {
     printk(KERN_ERR "fpga_jtag_init: couldn't get a major number.\n");
     return res;
   }
   printk(FPGA_JTAG_DRIVER_NAME"\r\n");
   for (i=0;i<=FPGA_JTAG_MAXMINOR;i++) minors[i]=0;
   initPortC();
   fpga_state&=~0xffff;
        return 0;
}



/* this makes sure that fpga_init is called during boot */

module_init(fpga_jtag_init);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Andrey Filippov <andrey@elphel.com>.");
MODULE_DESCRIPTION(FPGA_JTAG_DRIVER_NAME);

---