few ques ..

Hi dhruv86,

your message is unfortunately a little too brief hence I am not exactly sure what you were looking for but will take a stab:

1 - report timing b/w all inputs and outputs -- report timing -endpoints -- OR -- report timing -from [all::all_inps] -to [all::all_outs]
report timing -endpoints display the slack to all endpoints in the design. Does not sounds like what you want
report timing -from [all::all_inps] -to [all::all_outs] display the worst path between inputs and outputs
not sure what your needs are but you may want to do something like this instead
report timing -from [all des inps] -to [all des outs] -num_paths N
the all des syntax is a little cleaner and if you do -h there is a bunch of useful options there. The -num_paths is assuming you
do not only want the worst guy but a number of them
2 - max frequency for the block
foreach clk [find / -clock *] { report timing -to $clk }
This will display the WNS to each clock and then it is simple math to convert from period to frequency
3 - netlist hierarchy -- ungroup -flatten
Not sure what you want to do here. ungroup -flatten will remove all the hierarchy from the design. Usually that is not desirable
since it limits the tools ability to do resource sharing and the such. If all you want is a report you can simply use
report area
or
report hierarchy

good luck,
gh-