board/esd/common/xilinx_jtag/ports.c

   1 /*
   2  * (C) Copyright 2003
   3  * Stefan Roese, esd gmbh germany, stefan.roese@esd-electronics.com
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 /*******************************************************/
   9 /* file: ports.c                                       */
  10 /* abstract:  This file contains the routines to       */
  11 /*            output values on the JTAG ports, to read */
  12 /*            the TDO bit, and to read a byte of data  */
  13 /*            from the prom                            */
  14 /*                                                     */
  15 /*******************************************************/
  16
  17 #include <common.h>
  18 #include <asm/processor.h>
  19 #include <asm/io.h>
  20
  21 #include "ports.h"
  22
  23 static unsigned long output = 0;
  24 static int filepos = 0;
  25 static int oldstate = 0;
  26 static int newstate = 0;
  27 static int readptr = 0;
  28
  29 extern const unsigned char *xsvfdata;
  30
  31 /* if in debugging mode, then just set the variables */
  32 void setPort(short p,short val)
  33 {
  34         if (p==TMS) {
  35                 if (val) {
  36                         output |= JTAG_TMS;
  37                 } else {
  38                         output &= ~JTAG_TMS;
  39                 }
  40         }
  41         if (p==TDI) {
  42                 if (val) {
  43                         output |= JTAG_TDI;
  44                 } else {
  45                         output &= ~JTAG_TDI;
  46                 }
  47         }
  48         if (p==TCK) {
  49                 if (val) {
  50                         output |= JTAG_TCK;
  51                 } else {
  52                         output &= ~JTAG_TCK;
  53                 }
  54                 out_be32((void *)GPIO0_OR, output);
  55         }
  56 }
  57
  58
  59 /* toggle tck LH */
  60 void pulseClock(void)
  61 {
  62         setPort(TCK,0);  /* set the TCK port to low  */
  63         setPort(TCK,1);  /* set the TCK port to high */
  64 }
  65
  66
  67 /* read in a byte of data from the prom */
  68 void readByte(unsigned char *data)
  69 {
  70         /* pretend reading using a file */
  71         *data = xsvfdata[readptr++];
  72         newstate = filepos++ >> 10;
  73         if (newstate != oldstate) {
  74                 printf("%4d kB\r\r\r\r", newstate);
  75                 oldstate = newstate;
  76         }
  77 }
  78
  79 /* read the TDO bit from port */
  80 unsigned char readTDOBit(void)
  81 {
  82         unsigned long inputs;
  83
  84         inputs = in_be32((void *)GPIO0_IR);
  85         if (inputs & JTAG_TDO)
  86                 return 1;
  87         else
  88                 return 0;
  89 }
  90
  91
  92 /* Wait at least the specified number of microsec.                           */
  93 /* Use a timer if possible; otherwise estimate the number of instructions    */
  94 /* necessary to be run based on the microcontroller speed.  For this example */
  95 /* we pulse the TCK port a number of times based on the processor speed.     */
  96 void waitTime(long microsec)
  97 {
  98         udelay(microsec); /* esd */
  99 }