[PATCH] fpga zynq: Check the bitstream for validity

[jgunthorpe@obsidianresearch.com (Jason Gunthorpe)]

On Fri, Oct 28, 2016 at 01:06:08PM +0200, Matthias Brugger wrote:

> The only case we don't check is, if count == 0. If we check that here, we
> can get rid of the count <= 4 check.

You don't think

  if (count == 0 || buf[3] = 'x')
 
looks weird and wrong? I do.

> >The count <= 4 should stay here since it is primarily guarding against
> >read past the buffer in the if.
> 
> If you insist in doing this check, it should be count < 4, because we check
> the first four elements of buf, or do I miss something?

count = 4 and count = 0 are both invalid. A bitstream consisting of
only the sync word is also going to fail programming.

As Michal said, the actual min bitstream length is probably >> 50 bytes

Jason