[Parav]

I am referring to ARM 968 TRM section of draining write buffer.

TCM write buffer entry is 2 entry deep.
When we want to drain the TCM write buffer to connected TCM memory, are we supposed to drain in explicitly each time by executing MCR p15, 0, <Rd>, c7, c10, 4 to drain write buffers?

Or its one time setting that we can do during CPU initialization time?

Regards,
Parav Pandit

[ttfn]

You would need to re-execute the instruction every time you wished to force the write-buffers to drain. However, you should not need to do this often - in fact very rarely in my experience.

[Parav]

ttfn, on Aug 31 2010, 07:09 AM, said:

You would need to re-execute the instruction every time you wished to force the write-buffers to drain. However, you should not need to do this often - in fact very rarely in my experience.

Thanks for the information.
This is typically to access peripheral devices mapped via the TCM memory. Each time we access them we need to ensure that it reaches the device (before software asked for the completion of same).

How do we know whether its one time setting or required for each operation?
Like ITCM and DTCM enabling is one time setting.

How about DTCM/ITCM ordering enable/disable option? Is it one time operation during initialization stage or each time we need do it?