[U-Boot] BUG: bootz/bootm command mandates a fdt blob

[Simon Glass]

Hi,

On 20 November 2014 16:04, Hans de Goede <hdegoede at redhat.com> wrote:
> Hi Suriyan,
>
> On 11/20/2014 04:16 PM, Suriyan Ramasami wrote:
>> Hello Simon,
>>      This mail is addressed to you as the FDT support was added by
>> you. I am not sure who else to address it to.

Just to be clear, I didn't add FDT support, this predates my
involvement in U-Boot. I added CONFIG_OF_CONTROL etc. though. Han's
solution sounds good to me.

>>
>>       I find that if CONFIG_OF_LIBFDT is defined then the user is
>> forced to provide a FDT blob. In most of the cases it makes sense.
>> However, this removes the ability to boot older linux (non FDT).
>>     For example, I was looking at the Hardkernel Odroid kernels for
>> the U2/U3, and they are 3.8 based. Of course newer kernels 3.17 work.
>> For users to use the same boot loader for 3.8 and for 3.17, they
>> cannot use the mainline uboot.
>
> I've hit the same problem myself recently, see the thread titled:
>
> "Booting non devicetree enabled kernels using u-boot build with CONFIG_OF_LIBFDT"
>
>>     I was wondering if teh third argument to bootz/bootm etc could
>> also take the route of initrd (optional if - is specified) could be
>> implemented.
>>
>>    The fix seems to be trivial (or so I think), in file
>> common/image-fdt.c, but wanted to know your comments on this. Also the
>> command help (for bootz etc) states that if the 3rd argument is not
>> passed, then the bd_info struct is passed, and I do not see it being
>> passed in the code anywhere. In the absence of the third parameter, it
>> just gives a "No fdt found" message.
>
> Thanks for working on a fix, as discussed in the earlier thread, requiring
> a third argument which is '-' will break old boot.scr files and the likes,
> so a better fix is to:
>
> 1) Always try to find an ftd (to keep things like appended ftd-s working)
> 2) If not found see if there is a third argument, if there is, treat this
> as a fatal error, abort the bootm (iow behave as before)
> 3) If there is not a third argument warn and continue as before.
>
> If you could respin your patch to do this, then that would be great.
>
> Regards,
>
> Hans
>
>
>>
>> diff --git a/common/image-fdt.c b/common/image-fdt.c
>> index a39ae1b..e685700 100644
>> --- a/common/image-fdt.c
>> +++ b/common/image-fdt.c
>> @@ -243,7 +243,10 @@ int boot_get_fdt(int flag, int argc, char * const argv[], u
>>
>>         if (argc > 2)
>>                 select = argv[2];
>> -       if (select || genimg_has_config(images)) {
>> +       if (select && strcmp(select, "-") ==  0) {
>> +               debug("## Skipping fdt\n");
>> +               return 0;
>> +       } else if (select || genimg_has_config(images)) {
>>  #if defined(CONFIG_FIT)
>>                 if (select) {
>>                         /*
>>
>> Regards
>> - Suriyan
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>>

Regards,
Simon