Run Section - 2025.1 English - UG904

The Run section of the ECO Navigator, shown in the following figure, provides access to all the commands required to implement the current changes.

Figure 1. ECO Navigator Run Commands

Check ECO

Runs the ECO checks rule deck on the current design.

Tip: The Vivado tools allow you to make netlist changes unconditionally using the ECO commands. However, logical changes can lead to invalid physical implementation. Run the Check ECO function to flag any invalid netlist changes or new physical restrictions that need to be addressed before physical implementation can commence.

Optimize Logical Design

In some cases, it is desirable to run opt_design on the modified design to optimize the netlist. This command opens the Optimize Logical Design dialog box, allowing you to specify options for the opt_design command. Any options that are entered in the dialog box are appended to the opt_design command as they are typed. For example, to run opt_design -sweep, type -sweep under Options.

Figure 2. Optimize Logical Design Dialog Box

Place Design

For 7 series and UltraScale families, runs incremental place_design on the modified netlist as long as 75% or more of the placement can be reused. The Incremental Placement Summary at the end of place_design provides statistics on incremental reuse. Selecting this command opens the Place Design dialog box and allows you to specify options for the place_design command. Any options that are entered in the dialog box are appended to the place_design command as they are typed.

Refer to Incremental Implementation for additional information on Incremental Place and Route.

For Versal, place_design -eco command is used to invoke the ECO placer. By default, it supports timing driven mode. To invoke the non-timing driven mode, an extra switch -no_timing_driven is used. It places the unplaced or newly added cells. The addition of new cells is limited to 1% of the design utilization and the following restrictions should be observed:

• The new cells are limited to addition of Flops and LUTs.
• The ECO edits should not lead to changes in the clock solution.
• There should be no modifications to SLR crossings.
• In the DFX design, the changes should not impact boundary connections. Static modifications in child implementation runs are not supported.

To enable the ECO placer flow in timing driven mode in the Place Design Dialog Box, add options -eco as shown in the following figure. The Tcl command to invoke ECO placer is as follows:

place_design -eco

Figure 3. Place Design Dialog Box

To enable the ECO placer flow in the non timing driven mode in the Place Design Dialog Box, add options -eco -no_timing_driven as shown below. The Tcl command to invoke ECO placer is as follows: place_design -eco -no_timing_driven

Figure 4. Place Design Dialog Box

Optimize Physical Design

In some cases it is desirable to run phys_opt_design on the modified design to perform physical optimization on the netlist. This command opens the Optimize Physical Design dialog box and allows you to specify options for the phys_opt_design command. Any options that are entered in the dialog box are appended to the phys_opt_design command as they are typed. For example, to run phys_opt_design -fanout_opt, type -fanout_opt under Options.

Figure 5. Optimize Physical Design Dialog Box

Route Design

For 7 series and UltraScale families, selecting this command opens the Route Design dialog box. Depending on the selection, this command allows you to perform an Incremental Route of the modifications made to the design, Route the selected pin, or Route selected nets. If Incremental Route is selected on a modified netlist that has less than 75% of reused nets, the tool reverts to the non-incremental route_design.

Figure 6. Route Design Dialog Box

Refer to Incremental Implementation for additional information on Incremental Place and Route.

Depending on your selection, you have four options to route the ECO changes:

Incremental Route

This is the default option.

Route selected pin

This option limits the route operation to the selected pin.

Route selected non-Power nets

This option routes only the selected signal nets.

Route selected Power nets

This option routes only the selected VCC/GND nets.

For Versal, route_design -eco command is used to invoke the ECO router flow. It supports both timing driven and non timing driven modes. Use the finalize_eco command to ensure valid placement before calling the ECO router flow. Invalid site configurations resulting from ECO changes are fixed by finalize_eco.

If the ECO operation adds new cells, finalize_eco is not required and you can run place_design -eco to place the cells before routing. Otherwise, run finalize_eco before route_design -eco.

To enable the ECO router flow in the Route Design Dialog Box, add the options as shown in the following figure:

• -eco for timing driven flow
• -eco -no_timing_driven for non timing driven flow

finalize_eco
route_design -eco -no_timing_driven