[U-Boot] [PATCH v4] Fix board init code to use a valid C runtime environment

Albert ARIBAUD
2015-11-16T14:15:27Z

Hello Alexey,

On Mon, 16 Nov 2015 13:43:19 +0000, Alexey Brodkin
<Alexey.Brodkin@synopsys.com> wrote:
> Hi Albert,
>
> On Mon, 2015-11-16 at 14:34 +0100, Albert ARIBAUD wrote:
> > Hello Alexey,
> >
> > On Mon, 16 Nov 2015 13:12:15 +0000, Alexey Brodkin
> > <Alexey.Brodkin@synopsys.com> wrote:
> > > Hi Albert,
>
> > > >
> > > > - /* Allocate and zero GD, update SP */
> > > > - mov %r0, %sp
> > > > - bl board_init_f_mem
> > > > -
> > > > + /* Get reserved area size, update SP and FP */
> > > > + bl board_init_f_get_reserve_size
> > > > /* Update stack- and frame-pointers */
> > >
> > > I think we don't need to mention SP/FP update in comments twice here.
> > > I.e. either strip ", update SP and FP" from your introduced comment or
> > > which I really like more remove following line with comment entirely:
> > > ---------->8----------
> > > /* Update stack- and frame-pointers */
> > > ---------->8----------
> >
> > Not sure where you see two SP+FP 'update' comments here; probably
> > you're referring to the 'setup' comment on line 53 and the 'update'
> > one on line 59. If that is what you meant, I tink these comments are
> > different and deserve staying both...
>
> Ok, that's what I have after your patch application:
>
> ---------->8----------
> /* Setup stack- and frame-pointers */
> mov %sp, CONFIG_SYS_INIT_SP_ADDR
> mov %fp, %sp
>
> /* Get reserved area size, update SP and FP */
> bl board_init_f_get_reserve_size
> /* Update stack- and frame-pointers */ <-- that's already mentioned 2 lines above
> sub %sp, %sp, %r0
> mov %fp, %sp
> ---------->8----------

My bad, I'd missed that one. I'll turn

/* Get reserved area size, update SP and FP */

Into

/* Get reserved area size */

> > ... However, these comments also pretty much just paraphrase the code
> > which follows them and thus serve little purpose; they could be
> > reworded to show less of what is being done and more of why it is being
> > done:
> >
> > - the "Update stack- and frame-pointer" comment could be turned into
> > "Allocate reserved size on stack and adjust frame pointer
> > accordingly", and
> >
> > - the "Setup stack- and frame-pointers" comment could be turned into
> > "Establish C runtime stack and frame".
> >
> > Opinions?
>
> Totally agree, care to implement it?

That, and the removal of the repetition. v5 in approach.

> -Alexey

Amicalement,
--
Albert.