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

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.

      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 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.


Regards
- Suriyan

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.
> 
>       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
> _______________________________________________
> U-Boot mailing list
> U-Boot@lists.denx.de
> http://lists.denx.de/mailman/listinfo/u-boot
>

Hi,

On 20 November 2014 16:04, Hans de Goede <hdegoede@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
>> _______________________________________________
>> U-Boot mailing list
>> U-Boot@lists.denx.de
>> http://lists.denx.de/mailman/listinfo/u-boot
>>

Regards,
Simon