Shulou(Shulou.com)06/01 Report--

Editor to share with you the sample analysis of data input in PR, I believe that most people do not know much about it, so share this article for your reference, I hope you can learn a lot after reading this article, let's go to know it!

A bunch of init _ XXX variables are pre-defined in Innovus. You need to assign the corresponding input file to the corresponding variable, and then execute the init_design tool to read all the files in turn. For verilog netlist, there are several key init variables for flow:

Init_design_settop, the default value of this variable is 1, which means that the customer is required to specify the top name of the current design to the variable init_top_cell;. If the variable is set to 0, let the tool recognize the top. It is recommended that with the default value, the user specifies top.init_lef_file and assigns tech-lef + other lefs to this variable. Here is a problem. If a lef file is not added before init_design, what should I do to read it incrementally? In Innovus common ui, use the command: read_physical-add_lefs XX can be incrementally read into lef.

Init_mmmc_file, specify viewDefinition.tcl, library_set in viewDefinition specifies all the library to be used, rc_corner specifies the corresponding QRC file, and constraint_mode specifies the SDC file.

Init_verilog, specify the Netlist file.

Init_pwr_net, specify global power nets.

Init_gnd_net, specify global ground nets.

Init_cpf_file, if it is a multi-voltage domain design, is used to specify CPF files. If power intent is described by 1801, you cannot specify 1801 files with this variable. You need to use the command read_power_intent-1801 $1801_file to read it. If you use power domain in viewDefinition, you should read it before init_design, and then execute commit_power_intent after init_design. The command read_power_intent is used in the same way as Genus, with one more step apply_power_intent in Genus to bind the design to power domain and commit_power_intent to insert low power cell.

At this point, all input files are specified, execute init_design will read the corresponding files, init_design read the order has not yet seen, according to the logic to guess the reading order: library-> tech-lef-> lef-> QRC-> cpf-> netlist-> SDC.

In addition to the init_XXX variable that specifies the input file above, there is also an init_OOO variable that controls the input process:

Init_design_netlisttype, which is used to specify whether the format of netlist is verilog or OA. At present, the donkey only learns the verilog part, and all OA-related parts are ignored. Init_ignore_pgpin_polarity_check, which specifies the list of a leaf cell pin name, tells the tool to ignore polarity checking when globalNetConnect or connect supply net in CPF. This product doesn't seem to be useful for 1801 flow. I solved a related problem on Monday. The problem I encountered at that time was 1801 flow. In commit_power_intent, the tool reported Error: IMPDB-1220 and WARN: IMPDB-1278. For this problem, use the command dbGet [dbGet top.nets.name PMD0_VDD-p]. IsPwr in Innovus to check what the tool recognized the corresponding supply net as. In the case encountered by the old donkey, it was in 1801 that connect_supply_net was used to connect an analog Ground to an analog IP, but in 1801 only supply net was defined and the net was not specified for Ground, so the tool recognized it as Power. The solution is to create a supply set for it in 1801 and specify it as ground.

Init_verilog_tolerate_port_mismatch, the default value of this variable is 0. It cannot tolerate that the port defined by module is less than the port when instantiating. If it is set to 1, if the tool parses netlist and finds that module has less port than instantiated port, the tool will create a port on module. The donkey thinks this variable is especially useful when the design is dirty. Init_lef_check_mask_shifts, used to check whether there is a conflict between FIXEDMASK and LAYERMASKSHIFT in tech-lef and MACRO sections. The default value of this variable is off. If it is set to on, the tool will report an error and stop. If it is set to bypass, the tool will only report an error and will not stop. In fact, the donkey does not know how important FIXEDMASK and LAYERMASKSHIFT are in different processes. Put it here first, in case it is found to be important later. Init_import_mode, which is used to specify the option of setImportMode, such as set init_import_mode {- discardFloatingVNets true-keepEmptyModule true}. Here is a question: does innovus delete empty module by default? If so, it doesn't matter whether there is empty module in the comprehensive netlist or not, right? If so, why does some backend have to delete empty module? Init_design_uniquify, which controls whether innovus does uniquify when parsing netlist. Since innovus requires netlist to be unique, why not set the default value of this variable to 1?

The above is all the contents of the article "sample Analysis of data entry in PR". Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

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