how to use the cmem module's pool?

Hi ^^

currently, I am doing the implementation of video application.

First, I use the codec engine codec examples's viddec_copy.

and then working with dvsdk's decode application.

Q1) In the decode application's video.c, defined like bottom.

#define READBUFSIZE              3 * 1024 * 1024

3*1024*1024 = 3145728bytes.

also, In the CMEM module setting,

insmod cmemk.ko phys_start=0x87800000 phys_end=0x88000000 pools=1x3145728,3x829440,1x61440,1x10240

the first pool is equal to READBUFSIZE value.

what is that means?

what is the cmem pool? and how to use the cmem module's pool?

I read the http://processors.wiki.ti.com/index.php/Changing_the_DVEVM_memory_map#Sizing_and_partitioning_CMEM_memory

http://processors.wiki.ti.com/index.php/CMEM_Overview

But I don't know....^^;