reg: Establishing the Clock Tree

[jyothia]

Can anybody give a general guidelines to do cts for SoC. like how to start doing cts. I'm using Magma for CTS, and the report is very bad.

Also how can I do analysis of the same. A guideline will help a lot.

 

[vlsitechnology]

U want to know the details of CTS for SOC tool or Magma tool?

If u would like to know the details of soc encounter then i can help u out

Added after 4 minutes:

The general guidelines are generating clock tree specification file, specifying footprints.....These are the major steps..If ur clock tree specification file is not having proper constraints then ur CTS will not be good
And once u finish the CTS don't forget to set it in propagated mode by using
"set_propagated_mode - [all_clocks] "


If any help don't hesitate to ask me
Bye take care

 

[jyothia]

Hi,

Thanks for u'r i/p.

I was in general asking about the guidelines to do CTS.
Like on what basis I can do skew grouping and ceation of separate tree.
How I can take care about the clock gating etc.

If u' have any guideline on that please post it.

 

[useless_skew]

In SoC Encounter, CTS can be done in two modes :
1. Manual 2. Automatic

In manual mode, we have to specify the clock name, no. of levels, buffer to be used at each level and some other parameters.

In automatic mode, we can generate a clock specification file template and edit it if required, and use it for synthesizing the clock tree.

Use "ckSynthesis" command to synthesize the clock tree according to the specifications.

If there is a data path between two clock domains, we have to optimize the delays between both the trees by grouping both the clocks.

"ckSynthesis -check" gives the trace report in a file .cts_trace

The tool traces the clock tree automatically starting from the root pin.
CTS on gated clocks can be performed automatically. There is a parameter "NoGating" in the clock tree specification file which controls the CTS on gated clocks. If NoGating is set to no, (NoGating NO), skew balancing is not performed for the gated clock

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[NAresh123]

Any body is there ?????????????

 

[jyothia]

yes

 

[vamsi_addagada]

hi jyothi
u got any material for cts using the magma tool...... plz send that material to me .vamsi_addagada@yahoo.co.in

thanks
vamsi

 

[shiv_emf]

send it to shiv.emf@gmail.com