As John mentions, enabling the CPACF (feature code 3863) on
the new z9 processors just turns on the cipher instructions
(KM, KMC) documented in the latest zArch PoP manual. All z9
boxes come with these instructions disabled, possibly
because of export restrictions on strong cryptographic
hardware, and enabling them is a no charge operation. The
CAACF has nothing to do with the separate cryptographic
accelerators (PCxICC, PCICC, CCF) available as optional
hardware components.

A paper that provides a different perspective on explaining
the differences between secure key and clear key as well as
pointing out that CPACF alone does not replace the z900 CCF
Crypto processors can be found here:

http://www-1.ibm.com/support/docview.wss?uid=tss1td101704&aid=1

The KM and KMC instructions enabled by the CPACF feature
provide hardware support for DES, TDES and AES encryption
operations, in both ECB and CBC modes.

DJ

----- Original Message Follows -----
From: "McKown, John" <[EMAIL PROTECTED]>
To: [email protected]
Subject: Re: Crypto CPACF enablement
Date: Thu, 26 Apr 2007 10:29:50 -0500
>
> CPACF simply adds a number of instructions to the System
> z's instruction set. It does not speed up anything unless
> the software issues these instructions. So the question
> now becomes: Does the ???? program use these instructions?
> The most likely answer is: "No.". I doubt that the GCC
> compiler generates any of the CPACF instructions.
>
> Note that the CPACF added instructions are not a
> co-processor. They are simply "normal" instructions which
> are millicoded in the processor. They execute
> synchronously using the normal CP hardware.
>
> If you truly have one of the "coprocessor" cards, then the
> question again becomes: "Does the ??? software use this
> interface?" If it does, it is likely via an assembler
> level "lib*" module, and not "in line" instructions.
>

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