fsl_hash.c: Alignment problem when using caam_hash() for FIT images

[Stefan Roese]

Hi,

while working on an LX2160 based board and updating to latest mainline
I noticed problems using the HW accelerated hash functions on this
platform, when trying to boot a FIT Kernel image. Here the resulting
error message:

## Loading kernel from FIT Image at a0000000 ...
    Using 'conf-freescale_lx2160a.dtb' configuration
    Trying 'kernel-1' kernel subimage
    Verifying Hash Integrity ... sha256Error: Address arguments are not 
aligned
CAAM was not setup properly or it is faulty
  error!
Bad hash value for 'hash-1' hash node in 'kernel-1' image node
Bad Data Hash
ERROR: can't get kernel image!

And here the addresses, printed from caam_hash():
caam_hash (171): pbuf=00000000a00000fc pout=00000000fbde6f80 
buf_len=5291241 ARCH_DMA_MINALIGN=64

pbuf points to an area in the FIT image itself. So its not easy
to change this.

In some quick tests I've dropped the alignment check and have not seen
any problems yet. The hash is calculated without any problems and seems
to be okay. I might be just lucky though, not sure.

So my basic question is: Is this alignment really necessary and required
for both addresses in this function?

If yes, do you have some suggestions on how to handle this? Other than
allocating new aligned buffers in caam_hash() and memcpy'ing to those
new buffers instead. BTW, this is not a preferred solution for me, as
boot-time is crucial for my platform.

Thanks,
Stefan