Re: [PATCH] MIPS: malta: Set load address for 32bit kernel correctly

From: Maciej W. Rozycki
Date: Sun Apr 05 2020 - 13:23:07 EST


On Mon, 6 Apr 2020, Jiaxun Yang wrote:

> > Given the description above I think it should be done uniformly and
> >automatically across all platforms by trimming the address supplied
> >with
> >$(load-y) to low 8 digits in a single place, that is at the place where
> >
> >the variable is consumed. This will reduce clutter across Makefile
> >fragments, avoid inconsistencies and extra work to handle individual
> >platforms as the problem is triggered over and over again, and limit
> >the
> >risk of mistakes.
>
> I was intended to do like this but failed to find a proper way.
>
> Makefile isn't designed for any kind of calculation.
> And shell variables are 64-bit signed so it can't hold such a huge variable.
>
> Just wish somebody can give me a way to do like:
>
> ifndef CONFIG_64BIT
> load-y = $(load-y) & 0xffffffff
> endif

Use the usual shell tools like `sed', `cut', `awk', or whatever we use in
the kernel build already for other purposes. There's no need to do any
actual calculation here to extract the last 8 characters (and the leading
`0x' prefix). At worst you can write a small C program, compile it with
the build system compiler and run, as we already do for some stuff.

Maciej