[U-Boot] [PATCH] spl: fix entry_point equal to load_addr

[Simon Goldschmidt]

On Fri, Dec 6, 2019 at 2:49 PM Giulio Benetti
<giulio.benetti at benettiengineering.com> wrote:
>
> Hello Tom, all,
>
> On 12/6/19 2:34 PM, Tom Rini wrote:
> > On Fri, Dec 06, 2019 at 01:58:46PM +0100, Simon Goldschmidt wrote:
> >> On Fri, Dec 6, 2019 at 1:46 PM Patrice CHOTARD <patrice.chotard at st.com> wrote:
> >>>
> >>> Hi
> >>>
> >>> This patch is breaking the STM32MP15 basic boot (spl => u-boot).
> >>
> >> Looking at socfpga gen5 u-boot.img, this is probably broken as well.
> >>
> >> And I don't even see any RB or TB tags here :-(
> >
> > Ugh, what the heck?  I applied this because I looked over the changes
> > and they seemed correct.  I'm quite willing to just revert this but I
> > would like to know how it's breaking.  Sorry all!
> >
>
> IMHO this is due to wrong images creation with mkinage, especially when
> passing parameters with -a and -e flags.
>
> In my case I need them to be:
> -a 0x80002000 (load address) => CONFIG_SYS_TEXT_BASE
> -e 0x800023FD (entry point where SPL jumps to) => CONFIG_SYS_UBOOT_START

Well, CONFIG_SYS_UBOOT_START is only set in 15 files in include/configs, so I
guess a lot more boards might be broken...

>
> So *maybe* on STM32MP1 and other broken boards -e
> (CONFIG_SYS_UBOOT_START) is not equal to -a (CONFIG_SYS_TEXT_BASE) as
> was assumed before(but wrong).
>
> Indeed CONFIG_SYS_UBOOT_START is set to 0 if not specified in
> u-boot/Makefile:
> `
> # U-Boot entry point, needed for booting of full-blown U-Boot
> # from the SPL U-Boot version.
> #
> ifndef CONFIG_SYS_UBOOT_START
> CONFIG_SYS_UBOOT_START := 0
> endif
> `
>
> So probably broken boards try to jump to absolute 0.
> A solving patch would be:
> ifndef CONFIG_SYS_UBOOT_START
> CONFIG_SYS_UBOOT_START := CONFIG_SYS_TEXT_BASE
> endif

That might work, but I wonder if this is the correct time in the release to do
so.

Regards,
Simon

>
> What do you think?
>
> Sorry for this mess!
>
> Best regards
> --
> Giulio Benetti
> Benetti Engineering sas