[v2,1/3] crypto: ppc/sha256 - assembler

Herbert Xu herbert at gondor.apana.org.au
Fri Feb 27 20:51:21 AEDT 2015


On Fri, Jan 30, 2015 at 03:39:23PM +0100, Markus Stockhausen wrote:
> This is the assembler code for SHA256 implementation with
> the SIMD SPE instruction set. Although being only a 32 bit
> architecture GPRs are extended to 64 bit presenting two
> 32 bit values. With the enhanced instruction set we can
> operate on them in parallel. That helps reducing the time
> to calculate W16-W64. For increasing performance even more 
> the assembler function can compute hashes for more than 
> one 64 byte input block. That saves a lot of register
> saving/restoring
> 
> The state of the used SPE registers is preserved via the 
> stack so we can run from interrupt context. There might 
> be the case that we interrupt ourselves and push sensitive 
> data from another context onto our stack. Clear this area
> in the stack afterwards to avoid information leakage.
> 
> The code is endian independant.
> 
> Signed-off-by: Markus Stockhausen <stockhausen at collogia.de>

All applied.  Thanks!
-- 
Email: Herbert Xu <herbert at gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt


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