|  | # Copyright lowRISC contributors. | 
|  | # Licensed under the Apache License, Version 2.0, see LICENSE for details. | 
|  | # SPDX-License-Identifier: Apache-2.0 | 
|  |  | 
|  | # Interface configuration for JTAG on the Nexys Video board through the | 
|  | # FT2232H chip. This connection is labeled DTPI/DSPI in the board schematics. | 
|  |  | 
|  | # adapter speed | 
|  | # Up to 30 MHz are supported by the FT2232H | 
|  | adapter_khz 30000 | 
|  |  | 
|  | interface ftdi | 
|  | transport select jtag | 
|  |  | 
|  | ftdi_vid_pid 0x0403 0x6010 | 
|  |  | 
|  | # Not really required, but makes communication a bit more robust | 
|  | ftdi_tdo_sample_edge falling | 
|  |  | 
|  | # Use Channel A (0), channel B (1) is taken by Xilinx JTAG | 
|  | ftdi_channel 0 | 
|  |  | 
|  | # FT2232H pin configuration | 
|  | # | 
|  | # Documentation: | 
|  | # http://openocd.org/doc-release/html/Debug-Adapter-Configuration.html#Interface-Drivers | 
|  | # | 
|  | # Our configuration: | 
|  | # | 
|  | # Bit  MPSSE     FT2232    JTAG    Type   RstVal  Description | 
|  | # ---------------------------------------------------------------------- | 
|  | # Bit0 TCK       ADBUS0    TCK     Out    0       Clock Signal Output | 
|  | # Bit1 TDI       ADBUS1    TDI     Out    0       Serial Data Out | 
|  | # Bit2 TDO       ADBUS2    TDO     In     0       Serial Data In | 
|  | # Bit3 TMS       ADBUS3    TMS     Out    1       Select Signal Out | 
|  | # Bit4 GPIOL0    ADBUS4    nTRST   Out    1       General Purpose I/O | 
|  | # Bit5 GPIOL1    ADBUS5    nSRST   Out    1       General Purpose I/O | 
|  | # Bit6 GPIOL2    ADBUS6    0       Out    0       General Purpose I/O | 
|  | # Bit7 GPIOL3    ADBUS7    0       Out    0       General Purpose I/O | 
|  | # | 
|  | # Bit6 GPIOL2 is used to select between JTAG=1 and SPI=0 and controls | 
|  | # the I/O MUX inside the earlgrey_nexsysvideo. Static so it is only | 
|  | # mentioned in the init command below (makes it output value 1) | 
|  | # | 
|  | # Bit7 GPIOL3 is used to enable boot rom boot strap | 
|  | # | 
|  | # This corresponds to the following reset values (first number), and | 
|  | # in/out layout (second number): | 
|  | ftdi_layout_init 0x0078 0x00fb | 
|  |  | 
|  | # TAP reset (nTRST) | 
|  | ftdi_layout_signal nTRST -ndata 0x0010 | 
|  |  | 
|  | # System Reset (nSRST) | 
|  | ftdi_layout_signal nSRST -ndata 0x0020 | 
|  |  | 
|  | # FT2232 doesn't support open drain GPIO for reset pins | 
|  | reset_config srst_push_pull trst_push_pull |