this is alternate version of linux fix:
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| commit 412c98c
| Author: Steve Cornelius <steve.cornelius@freescale.com>
| Date:   Mon Jun 15 16:52:59 2015 -0700
|
| crypto: caam - fix RNG buffer cache alignment
|
| The hwrng output buffers (2) are cast inside of a a struct (caam_rng_ctx)
| allocated in one DMA-tagged region. While the kernel's heap allocator
| should place the overall struct on a cacheline aligned boundary, the 2
| buffers contained within may not necessarily align. Consenquently, the
| ends of unaligned buffers may not fully flush, and if so, stale data will be
| left behind, resulting in small repeating patterns.
|
| This fix aligns the buffers inside the struct.
|
| Note that not all of the data inside caam_rng_ctx necessarily needs to
| be DMA-tagged, only the buffers themselves require this. However, a fix
| would incur the expense of error-handling bloat in the case of allocation
| failure.
|
| Cc: stable@vger.kernel.org
| Signed-off-by: Steve Cornelius <steve.cornelius@freescale.com>
| Signed-off-by: Victoria Milhoan <vicki.milhoan@freescale.com>
| Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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instead we will use just dma_alloc()

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>