Wrap function importance in Cache lines ?

[rakesh_aadhimoolam]

Hello everybody,

what is the function of Wrap in cache line implementations
how is it implemented

i know Wrap addressing - Wrap 8 word - x34 x38 x3c x20 x24 x28 x2c x30

but what is the importance of the Wrap function
why is it used in cache lines

Thanks
Help Appreciated

 

[sakhamuri063]

Wrap 8 word - x34 x38 x3c x20 x24 x28 x2c x30

For example, take the wrap 8 sequence you mentioned. If Processor wants to access, 0x2c data from memory. If only INCR8 is supported, Cache will issue transaction starting 0x20 on the bus. So, Bus will respond with initial data of 0x20..So, your processor need to wait till bus responds data for 0x2c. If you issue WRAP8 instead of INCR8, Bus will issue data for 0x2c address instead of 0x20 which will help processor getting data few cycles earlier compared to INCR8 case.

Hope it helps..