The resulting report in the
write_device_image
log looks nearly identical, but the file name
for the
.bif
will be slightly different:
Creating bitstream...
Tandem stage1 bitstream contains 23552 bits.
Writing CDO partition ./design_1_wrapper_tandem1.rcdo...
Writing NPI partition ./design_1_wrapper_tandem1.rnpi...
Creating bitstream...
Tandem stage2 bitstream contains 5939712 bits.
Writing CDO partition ./design_1_wrapper_tandem2.rcdo...
Writing NPI partition ./design_1_wrapper_tandem2.rnpi...
Writing NPI partition ./design_1_wrapper_shutdown.txt...
Generating bif file ./design_1_wrapper_tandem1.bif for Tandem stage-1.
In addition to the files mentioned above, the resulting run creates two
.pdi
images for this
design called
design_1_wrapper_tandem1.pdi
and
design_1_wrapper_tandem2.pdi
.
The _tandem1 and _tandem2 suffixes are automatically added to differentiate the stages.
Note: Tandem PDI generation for new devices is gated until a device reaches production status. A
parameter is available to build images for pre-production or ES silicon; contact support for information and
to confirm that there are no issues with the new device. Without the parameter, write_device_image is
expected to fail with the following error:
ERROR: [Vivado 12-4165] Tandem Configuration bitstream generation is not supported for part <device>.
IMPORTANT! Do NOT use this solution on engineering silicon (ES1) for VC1902, VC1802 or VM1802
devices.
In Ult, the Field Updates solution enables you to build “Reconfigurable Stage Twos”
where one could not only pick a stage 2 image from a list of compatible images, but then also
reconfigure that stage 2 area with another stage 2 image to provide dynamic field updates. In
Versal, the first part (for the initial boot of a device) may be supported in the future to allow you
to lock a stage 1 image in a small local boot flash; the second part (dynamic reconfiguration) will
require a DFX-based approach to allow for dynamic reconfiguration of a subsection of
the PL. This capability is not yet implemented as of Vivado 2022.2.
For test and debug purposes the
HD.TANDEM_BITSTREAMS
property can be set on the
implemented design before
.pdi
file generation to separate a single Tandem PROM
.pdi
file
into separate
tandem1.pdi
and
tandem2.pdi
files.
set_property HD.TANDEM_BITSTREAMS Separate [current_design]
Similarly, the behavior of Tandem PROM or Tandem PCIe file generation can be disabled entirely
by using the
HD.TANDEM_BITSTREAMS
property on the implemented design before
.pdi
file
generation. The following command can be used to do this.
set_property HD.TANDEM_BITSTREAMS NONE [current_design]
Chapter 2: Tandem Configuration
PG346 (v3.3) November 16, 2022
CPM Mode for PCI Express
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