- Jun 1, 2017
Most of what you write is on the IOD. The PSP with SEV etc. is used for the PRO variants (even on mobile chips), so can't really be cut. I'm still not even sure the PSP is distinct from the ARM core responsible for SCF. I don't think there is much savings to be had on the CCDs with the split you propose.Zen4 server chips (IOD+CCD) will have a lot of things which will not see any use in desktop (HEDT maybe), GenZ/CCIX/CXL support, CCP (Crypto Co Processor), IFIS (IF Intersocket), SEV stuffs...
From die area and efficiency perspective it is redundant and rather detrimental I would say. Of course it is a tradeoff vs reusability but for power efficency every little pJ saved counts.
They did not reuse CCDs for Mobile for this reason. But the more they can strip off irrelavant blocks the better it is for space and energy efficiency.
They always scale down their server cores, instead of a purpose built Mobile core. This hurts the efficiency and therefore market perception.
They will have N5P on their Zen4 products, might as well extract maximum energy efficiency of the node with a purpose built SoC for Mobile.