tcl/fpga/xilinx-xadc.cfg

   1 # SPDX-License-Identifier: GPL-2.0-or-later
   2
   3 # Xilinx XADC support for 7 Series FPGAs
   4 #
   5 # The 7 Series FPGAs contain an on-chip 12 bit ADC that can probe die
   6 # temperature, internal power supply rail voltages as well as external
   7 # voltages. The XADC is available both from fabric as well as through the
   8 # JTAG TAP.
   9 #
  10 # This code implements access through the JTAG TAP.
  11 #
  12 # https://www.xilinx.com/support/documentation/user_guides/ug480_7Series_XADC.pdf
  13
  14 # build a 32 bit DRP command for the XADC DR
  15 proc xadc_cmd {cmd addr data} {
  16         array set cmds {
  17                 NOP 0x00
  18                 READ 0x01
  19                 WRITE 0x02
  20         }
  21         return [expr {($cmds($cmd) << 26) | ($addr << 16) | ($data << 0)}]
  22 }
  23
  24 # XADC register addresses
  25 # Some addresses (status registers 0-3) have special function when written to.
  26 proc XADC {key} {
  27         array set addrs {
  28                 TEMP 0x00
  29                 LOCK 0x00
  30                 VCCINT 0x01
  31                 VCCAUX 0x02
  32                 VAUXEN 0x02
  33                 VPVN 0x03
  34                 RESET 0x03
  35                 VREFP 0x04
  36                 VREFN 0x05
  37                 VCCBRAM 0x06
  38                 SUPAOFFS 0x08
  39                 ADCAOFFS 0x09
  40                 ADCAGAIN 0x0a
  41                 VCCPINT 0x0d
  42                 VCCPAUX 0x0e
  43                 VCCODDR 0x0f
  44                 VAUX0 0x10
  45                 VAUX1 0x11
  46                 VAUX2 0x12
  47                 VAUX3 0x13
  48                 VAUX4 0x14
  49                 VAUX5 0x15
  50                 VAUX6 0x16
  51                 VAUX7 0x17
  52                 VAUX8 0x18
  53                 VAUX9 0x19
  54                 VAUX10 0x1a
  55                 VAUX11 0x1b
  56                 VAUX12 0x1c
  57                 VAUX13 0x1d
  58                 VAUX14 0x1e
  59                 VAUX15 0x1f
  60                 SUPBOFFS 0x30
  61                 ADCBOFFS 0x31
  62                 ADCBGAIN 0x32
  63                 FLAG 0x3f
  64                 CFG0 0x40
  65                 CFG1 0x41
  66                 CFG2 0x42
  67                 SEQ0 0x48
  68                 SEQ1 0x49
  69                 SEQ2 0x4a
  70                 SEQ3 0x4b
  71                 SEQ4 0x4c
  72                 SEQ5 0x4d
  73                 SEQ6 0x4e
  74                 SEQ7 0x4f
  75                 ALARM0 0x50
  76                 ALARM1 0x51
  77                 ALARM2 0x52
  78                 ALARM3 0x53
  79                 ALARM4 0x54
  80                 ALARM5 0x55
  81                 ALARM6 0x56
  82                 ALARM7 0x57
  83                 ALARM8 0x58
  84                 ALARM9 0x59
  85                 ALARM10 0x5a
  86                 ALARM11 0x5b
  87                 ALARM12 0x5c
  88                 ALARM13 0x5d
  89                 ALARM14 0x5e
  90                 ALARM15 0x5f
  91         }
  92         return $addrs($key)
  93 }
  94
  95 # Select the XADC DR
  96 proc xadc_select {tap} {
  97         set XADC_IR 0x37
  98         irscan $tap $XADC_IR
  99         runtest 10
 100 }
 101
 102 # XADC transfer
 103 proc xadc_xfer {tap cmd addr data} {
 104         set ret [drscan $tap 32 [xadc_cmd $cmd $addr $data]]
 105         runtest 10
 106         return [expr "0x$ret"]
 107 }
 108
 109 # XADC register write
 110 proc xadc_write {tap addr data} {
 111         xadc_xfer $tap WRITE $addr $data
 112 }
 113
 114 # XADC register read, non-pipelined
 115 proc xadc_read {tap addr} {
 116         xadc_xfer $tap READ $addr 0
 117         return [xadc_xfer $tap NOP 0 0]
 118 }
 119
 120 # convert 16 bit register code from ADC measurement on
 121 # external voltages (VAUX) to Volt
 122 proc xadc_volt {code} {
 123         return [expr {$code * 1./(1 << 16)}]
 124 }
 125
 126 # convert 16 bit temperature measurement to Celsius
 127 proc xadc_temp {code} {
 128         return [expr {$code * 503.975/(1 << 16) - 273.15}]
 129 }
 130
 131 # convert 16 bit suppply voltage measurement to Volt
 132 proc xadc_sup {code} {
 133         return [expr {$code * 3./(1 << 16)}]
 134 }
 135
 136 # perform a single channel measurement using default settings
 137 proc xadc_single {tap ch} {
 138         set cfg0 [xadc_read $tap [XADC CFG0]]
 139         set cfg1 [xadc_read $tap [XADC CFG1]]
 140         # set channel
 141         xadc_write $tap [XADC CFG0] $cfg0
 142         # single channel, disable the sequencer
 143         xadc_write $tap [XADC CFG1] 0x3000
 144         # leave some time for the conversion
 145         runtest 100
 146         set ret [xadc_read $tap [XADC $ch]]
 147         # restore CFG0/1
 148         xadc_write $tap [XADC CFG0] $cfg0
 149         xadc_write $tap [XADC CFG1] $cfg1
 150         return $ret
 151 }
 152
 153 # measure all internal voltages
 154 proc xadc_report {tap} {
 155         xadc_select $tap
 156         echo "TEMP [format %.2f [xadc_temp [xadc_single $tap TEMP]]] C"
 157         foreach ch [list VCCINT VCCAUX VCCBRAM VPVN VREFP VREFN \
 158                 VCCPINT VCCPAUX VCCODDR] {
 159                 echo "$ch [format %.3f [xadc_sup [xadc_single $tap $ch]]] V"
 160         }
 161 }