Cadence Foundation flow and db Tcl commands in Encounter

Cadence Foundation flowCadence Foundation flow s(FF) are the recommended procedures for implementing flat, hierarchical, and low-power/CPF designs using the EDI system softwareFF provides a set scripts that gives an easy way to automate these flowsThe scripts generated from FF are a starting point for building an implementation environment, but we can customize the scripts at various points in the flow

OverviewSpecifying the flow to runScripts for steps in the flowSubscriptsPlug-in scripts

Overview Inputs for FF aresetup.tcledi_config.tcllp_config.tclThe setup.tcl contains a single source of all design data required to run designThe edi_config.tcl contains flow variables which can be used to customize the flowThe lp_config.tcl file is used for low power designs

Using input files for FF, we can run Cadence genflow script to create the implementation environment with run scriptsFor any customization in the flow, edit setup.tcl, edi_config.tcl and lp_config.tcl

Specifying the flow to runThe EDI system software selects the flow to run as followsIf the vars(cpf_file) variable is defined, the low-power flow is runIf the vars(partition_list) variable is defined, the hierarchical flow is runIf neither of these flows is defined, the flat flow is run

Scripts for steps in the flowEach script runs independently, starting from the database created by the previous step and creating a database when it completes

SubscriptsIn addition to the setup.tcl script, the flow scripts use the following subscripts internallyutils.tcl common procedure for all foundation flowsprocs.tcl procedures that execute the EDI foundation flows

Plug-in scriptsTo customize the flow, plug-ins can be added into the flowThese plug-ins lets us to include design-specific requirements while leaving the flow scripts unchangedCreate a plug-in file in PLUG directory and place it in edi_config.tcl file

Db tcl commandsEDI uses tcl shell for user command-line interfaceFor each and every operation we do will have equivalent tcl command. This tcl command can be found in encounter.cmd file

Db commandsTcl commands in EDI are 3 typesPre defined commands with existing functionalityFe-tcl commandsDb tcl commands

Pre-defined commandsThese pre-defined commands will have a defined functionality and can be found in EDI command referenceThese commands does a specific task as explained in the command referencee.g. placeDesign --- placed all instancesCan be only used as the commands in tcl procedure script

Fe-tcl commandsThese fp-tcl commands are set of tcl procedures which can be used to query data inside EDIThere are atleast around 3000 fp-tcl commands in EDIVery hard to rememberCan be used to write our own tcl procedure scripts

Example fe tcl script

proc user_get_all_ios { } { set ioList {} dbForEachCellFTerm [dbgTopCell] ftermId { set ioList [concat $ioList [dbFTermName $ftermId]] } return $ioList}

Db-tcl commandsNew and very fast way of accessing the data from EDINo need to remember so many commandsVery much helpful for tcl programming and automaton in EDI

Using a single question mark will show you a list of the attributes available at this level. > dbGet head.? > head: allCells dbUnits layers mfgGrid objType propsTo list all the attributes AND their values use a double question markAnother starting point using dbget is topUsing top, we can access all design based infoE.g. Examples using dbget>dbget head.layers.name>YM0 M1 M2 M3 M4 M5 M6 M7 M8 M9 CA V1 V2 V3 V4 V5 V6 V7 V8 OVERLAP>dbget top.name