[PATCH v2 4/4] riscv: dts: starfive: don't use a default configuration

[Heinrich Schuchardt]

On 10.02.25 14:08, Simon Glass wrote:
> Hi Heinrich,
> 
> On Mon, 10 Feb 2025 at 04:18, Heinrich Schuchardt
> <heinrich.schuchardt at canonical.com> wrote:
>>
>> Booting JH7110 systems with a VisionFive 2 device-tree used to kind of
>> work without causing harm to the hardware. But there is no guarantee
>> that this will hold true in future. So we should not rely on it.
>>
>> Before the current patch series booting failed on unsupported boards due
>> to the lack of a device-tree in the binman generated default configuration
>> when reaching main U-Boot.
>>
>> By setting the default configuration to non-matching value booting will
>> now fail on unsupported boards already in SPL. This allows SPL to
>> continue with the next boot source for a possible recovery.
>>
>> Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt at canonical.com>
>> ---
>> v2:
>>          new patch
>> ---
>>   arch/riscv/dts/starfive-visionfive2-binman.dtsi | 13 +++++++++++++
>>   1 file changed, 13 insertions(+)
>>
>> diff --git a/arch/riscv/dts/starfive-visionfive2-binman.dtsi b/arch/riscv/dts/starfive-visionfive2-binman.dtsi
>> index 05787bdb92d..dd0faca6824 100644
>> --- a/arch/riscv/dts/starfive-visionfive2-binman.dtsi
>> +++ b/arch/riscv/dts/starfive-visionfive2-binman.dtsi
>> @@ -13,6 +13,19 @@
>>   };
>>
>>   &binman {
>> +       itb {
>> +               fit {
>> +                       configurations {
>> +                               /*
>> +                                * Do not boot if there is no matching
>> +                                * configuration. We can't remove the default
>> +                                * here. So use a non-matching value.
>> +                                */
>> +                               default = "none";
> 
> The 'default' is optional [1] but the spec is silent on what happens
> when the default is missing. What do you think it should do? Perhaps
> we should add a property to define the behaviour?

If there is no match and default does not exist, we should not boot.

In our current code we don't boot if default points to a non-existing 
config. But having inconsistent FIT images might not be the best idea.

Maybe it would be better to use

#ifndef CONFIG_MULTI_DTB_FIT
	default = "conf-1";
#endif

in arch/riscv/dts/binman.dtsi to avoid having an invalid default value?

Best regards

Heinrich

> 
>> +                       };
>> +               };
>> +       };
>> +
>>          spl-img {
>>                  filename = "spl/u-boot-spl.bin.normal.out";
>>
>> --
>> 2.47.1
>>
> 
> Regards,
> SImon
> 
> [1] https://fitspec.osfw.foundation/#id4