crypto: caam: use dma_alloc_coherent instead of dma_alloc ...

dma_alloc return non-coherent memory, but the driver does no cache
maintenance on the buffer, causing memory corruption. Fix this by
requesting coherent memory for the DMA transfer.

Fixes: ef4144b4ab63 (crypto: caam - fix RNG buffer cache alignment)
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>

crypto: caam - fix RNG buffer cache alignment ...

this is alternate version of linux fix:
---------------------------------------------------------------------
| 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>
---------------------------------------------------------------------

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>

caamrng: port to hwrng framework ...

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

crypto: add i.MX6 CAAM support ...

Add the i.MX6 crypto core CAAM with support for the random number
generator.

The core itself works with jobrings in which descriptors can be
queued/dequeued for processing. Depending on descriptor type
the CAAM unit then either produces random numbers or decrypts/encrypts
data.

The code is based on the Linux v4.1 driver of the same name
without all the crypto/hashing components.

Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>