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From: David Laight <David.Laight@ACULAB.COM>
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Subject: RE: ibmvtpm byteswapping inconsistency
Thread-Topic: ibmvtpm byteswapping inconsistency
Thread-Index: AQHSfUel8lHqrdS2Gkm+aOCXywnIf6FV1AMQ
Date: Thu, 2 Feb 2017 15:17:19 +0000
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From: Michal Suchánek
> Sent: 02 February 2017 11:30
...
> The word is marked correctly as __be64 in that patch because count and
> handle are swapped to BE when saved to it and the whole word is then
> swapped again when loaded. If you just load ((u64)IBMVTPM_VALID_CMD <<
> 56 | ((u64)VTPM_TPM_COMMAND << 48) | ((u64)count << 32) |
> ibmvtpm->rtce_dma_handle in a register it works equally well
> without any __be and swaps involved.

And that version will almost certainly generate much better code.

	David