|
发表于 2012-2-3 17:18:05
|
显示全部楼层
这是synopsys官网的一段问答!
Reusing '-view existing_dft' as '-view spec' for set_dft_signal
Question:
In DFT Compiler, I have defined the scan_in and scan_out ports by using the
'set_dft_signal -view existing_dft' command.
Why are these ports being used for insert_dft?
Answer:
This is done to make the scan reordering flow in Physical Compiler simpler.
Now, you do not need to use the following commands to redefine the same
scan_in and scan_out ports :
'set_dft_signal -view existing_dft' (for DRC purposes)
'set_dft_signal -view spec' (for inserting scan structures)
For the scan reordering flow in Physical Compiler, you read in a scan stitched
netlist.You use the descriptive view i.e the '-view existing' option to
declare all the existing DFT signals and also to define a scan path.
This is followed by the 'create_test_protocol' and 'dft_drc' commands to extract
the scan chain information.
You can run the 'report_scan_path' command to verify the scan chains.
The reordering then takes place based on placement. You run insert_dft (-physical)
which automatically reuses the extracted scan chain information
(i.e. reusing "existing_dft" as "spec").
Hence, you do not have to re-specify the scan_in and scan_out ports with
the '-view spec'option.
A sample script for the extraction would be:
# Read in the netlist
read_verilog SRC/RISC_CORE.v
link
current_design RISC_CORE
# Define the scan chains
set_scan_configuration -style multiplexed_flip_flop
set_dft_signal -view existing_dft -type ScanDataIn -port TEST_SI
set_dft_signal -view existing_dft -type ScanDataOut -port TEST_SO
set_dft_signal -view existing_dft -type ScanEnable -port TEST_SE
set_scan_path chain1 -view existing_dft -scan_data_in TEST_SI -scan_data_out TEST_SO
# Define the test signals
set_dft_signal -view existing_dft -type ScanClock -port CLK -timing [list 45 55]
set_dft_signal -view existing_dft -type Reset -port RESETN -active_state 0
# Extract scan chains
create_test_protocol
dft_drc
report_scan_path -view existing_dft -chain all
report_scan_path -view existing_dft -cell all
For the reordering in Physical Compiler, in addition to the above you would
require the following commands:
preview_dft -physical
insert_dft -physical
dft_drc |
|