RE: ibmvtpm byteswapping inconsistency

From	David Laight <David.Laight@ACULAB.COM>
Newsgroups	linux.kernel
Subject	RE: ibmvtpm byteswapping inconsistency
Date	2017-02-02 16:20 +0100
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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

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Re: ibmvtpm byteswapping inconsistency Vicky <honclo@linux.vnet.ibm.com> - 2017-02-02 05:50 +0100
  Re: ibmvtpm byteswapping inconsistency Michael Ellerman <mpe@ellerman.id.au> - 2017-02-02 12:00 +0100
  Re: ibmvtpm byteswapping inconsistency Michal Suchánek <msuchanek@suse.de> - 2017-02-02 12:50 +0100
    RE: ibmvtpm byteswapping inconsistency David Laight <David.Laight@ACULAB.COM> - 2017-02-02 16:20 +0100

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