[U-Boot] [PATCH 2/2 v12] Introduced btrfs file-system with btrload command

[Wolfgang Denk]

Dear Adnan Ali,

In message <81c88340404a46b9a36590eded5e3c77 at codethink.co.uk> you wrote:
>
> >> > - Compare the code for crc32c_cal() in the patch with the 
> >> definition
> >> >    of DO_CRC(x) in "lib/crc32.c" - to me, it appears to be the 
> >> same for
> >> >    little endian code (it is redundant?), but different for big 
> >> endian
> >> >    systems - which raises the question if this code has ever been
> >> >    tested on a BE machine?
> >>          My code uses lib/crc32.c and i have only tested it on
> >>        mx53loco manchine.
> >
> > I tend to believe thatit will not work on a big endian system, then.
>       Sorry I meant to say my code uses lib/crc32_c.c. The lib/crc32.c
>   is main line so you think main line code is not for big endian.
>   What can i say.

What exactly do you mean by "my code uses lib/crc32_c.c?  I was
referring to the crc32c_cal() funciton in your patch.  It is this
function where I think it will fail on BE systems.

> >> > - The code claims to be derived from "Linux kernel 
> >> crypto/crc32c.c";
> >> >    but I cannot find such code in that file.
> >>        I think yes but part of part from syslinux. I have also added
> >>      SHA1 of commit so don't know.
> >
> > Please provide an exact reference where this code is coming from.
>     Just clone syslinux and code is in ~/syslinux/core/fs/btrfs/crc32c.h

The pelase fix the comment, and provide exact reference (commit ID
etc. as described at bullet # 4 at [1]) for that code.

[1] http://www.denx.de/wiki/view/U-Boot/Patches#Attributing_Code_Copyrights_Sign

> >> > - The implementation of crc32c_cal() suffers from a few other problems
> >> >    (like not triggering the watchdog, which will cause problems on
> >> >    systems that use one).
> >>        I think that is true as its not using main line crc32 code.
> >
> > We probably should do that, then.
>    To use that code probably i need to create static crc32 table.

Indeed.  This should also reduce boot time.

Best regards,

Wolfgang Denk

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