rahulgarg

LDS : More info requested

Discussion created by rahulgarg on Sep 10, 2008
Latest reply on Oct 30, 2008 by MicahVillmow
I am going through the CAL documentation. In the IL reference, I can see LDS can now be accessed for RV770. However I am not clear on the programming model.

Can AMD provide a short overview of the programming model for LDS?
I can see that threads are now arranged into thread groups and that one can access a thread group id, thread id within group and also absolute thread id. But I am not clear about how threads are arranged into groups and whether the thread group is the same as a wavefront. Somewhat surprisingly, all thread ids and group ids etc are one dimensional.

For LDS, it appears that each thread "owns" a piece of LDS. Each thread can read from any portion of the LDS but can only write to the portion it owns. Is this understanding correct?

Please provide the following :
a) overview of how threads are arranged into groups?
b) Overview of LDS and how it can be used?

Till then I will look at samples provided and will try and deconstruct whats happening.

thanks,
rahul

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