mcmm mv ilm app note

8/3/2019 Mcmm Mv Ilm App Note

1/3

Creating ILMs

MULTICORNER-MULTIMODE MULTIVOLTAGE

create_ilm -scenarios

The scenario list must contain all scenarios that are required for thetop-level flow. If you do not specify the -scenarios option, all

scenarios are considered for ILM creation.

create_ilm

At a minimum, the ILM must be track assigned to be used for signal integrity analysis at the top level. You must create the ILM using the -include_xtalk option of the create_ilm command to use it for signal integrity analysis at the top level.Note:

To check if the ILM can be used during post-route stages and signal integrity stages of the top-level flow, see the following section of the report generated by

the report_ilm command:

Parasitics data present in the ILM:

-----------------------------------

RC data : Available

CC data : Available

SI aggressor data : Available


2/3

Reporting ILMs

MULTICORNER-MULTIMODE MULTIVOLTAGE

Use the report_ilm command to,

a)Report the TLUPlus files used in the different scenarios in the block-levelimplementation:

TLU+ files used:

----------------

Scenario #0: s1

Min TLU+ file : s1_min.tlup

Max TLU+ file : s1_max.tlup

Tech2ITF mapping file : s1_tlup.map

b)Report the TLUPlus files and the different temperature cornersconsidered in the block level implementation.

----------------------------------------

TLU+ file used Temperature(s)

----------------------------------------

s1_max.tlup 125.00s1_min.tlup -25.00

----------------------------------------

c) Report the top-level and ILM multicorner-multimode scenario mappingthat you specify using the select_block_scenario command.

Top-level and ILM scenario mapping:

-------------------------------------------------

Top-level scenario Reference ILM ILM scenario

-------------------------------------------------

top_scenario1 my_ilm_ref ilm_scenario1

-------------------------------------------------

(Only user-specified mappings are reported)

The report_ilm command reports the power domain information within

the ILM.

UPF power domain present in the ILM:

-------------------------------------------------

Power Domain : Block/PD

Current Scope : Top

Elements : Block

Available Supply Nets : Only primary and ground nets

available on this domain.

Connections -- Power -- -- Ground --

Primary: (Max Op. Voltage) Block/VDD (0.99) Block/VSS (0.00)

----------------------------------------------------------

Power Domain : Block/Subblock_PD

Current Scope : Top

Elements : Block/Subblock

Available Supply Nets : Only primary and ground nets

available on this domain.

Connections -- Power -- -- Ground --

Primary: (Max Op. Voltage) Block/VDD (0.99) Block/VSS (0.00)

--------------------------------------------------------


3/3

Using ILMs in the Top-Level Flow

MULTICORNER-MULTIMODE MULTIV

Setup

IC Compiler supports the following features:

Name mismatch between the top-level design and the ILM A multicorner-multimode ILM with a non multicorner-multimode top-level design A non multicorner-multimode ILM with a multicorner-multimode top-level design More modes in the top-level design than in the ILM More temperature corners, TLUPlus files at the top-level design

Use this only in the initial stages of the design development because the parasitic information from the block-level is used

as is at the top-level.

For more details, see Using Hierarchical Models chapter in the IC Compiler User Guide.

Top-level supply net c

on ILM. So you must

pin exists on the FRAMthe change_macro

FRAM command.

Applying Top

Level

Constraints

Use the read_sdc command to read the full-chip constraints. Verify that there are no conflicts between the full-chip

constraints and the constraints applied to the blocks before the ILM creation by using the check_physical_design

command.

While using case-analysis constraints during block-level implementation, you must set the same case-analysis constraintsfrom the top level onto the ILM. Case analysis usage at the block level can be detected through the ILM-123 error

messages and ILM-160 information messages in the log file created by the check_physical_design command.

All the UPF constraint

propagated to the to

reapply the UPF cons

voltage area for the I

place_opt or

clock_opt or

route_opt

These rules apply during the execution of the core commands:

ILM is considered as a dont_touch cell during top-level optimization. So optimization is not performed within the ILMs. To perform over-the-block routing by using the available resources in the block, you must change to the FRAM view of the block using the change-ref block_ref_name -view FRAM command.

Signal Integrity

To prevent crosstalk between top level nets and ILM nets follow these steps:

In the block-level implementation, use signal-integrity-aware optimization with the route_opt command to fix all block timing and signal integr Provide shielding for the blocks. For more details, see theAdding Block Shielding to Plan Groups or Soft Macros section in the Creating and Shaping

in the IC Compiler Design Planning User Guide

mcmm mv ilm app note

Documents