[PATCH] spl: Add function called after fpga image upload

[Taedcke, Christian]

Am 10.07.2023 um 15:44 schrieb Marek Vasut:
> On 7/10/23 15:02, Taedcke, Christian wrote:
>> Am 10.07.2023 um 13:41 schrieb Michal Simek:
>>>
>>>
>>> On 6/27/23 11:04, christian.taedcke-oss at weidmueller.com wrote:
>>>> From: Christian Taedcke <christian.taedcke at weidmueller.com>
>>>>
>>>> This way custom logic can be implemented per board after the fpga
>>>> image is uploaded.
>>>
>>> What do you want to do there?
>>
>> I have 2 use-cases for this:
>> 1. Clear the RAM which contained the bitstream (memset to zero). This 
>> should happen independed of the result of the upload operation.
> 
> Is this some "secure-boot" related item ?

Not directly. This only helps reducing the time the decrypted bitstream 
is stored in RAM.

> 
>> 2. Control a LED based on the upload result. So in case the upload 
>> failed, i want to enable some error LED.
>>
>> One issue is that the return values of spl_fit_load_fpga() or 
>> spl_fit_upload_fpga() are not evaluated in common/spl
>> /spl_fit.c. So this error is not propagated to higher layers.
>>
>> I my use-case uploading the bitstream is mandatory before starting 
>> u-boot.
>>
>>>
>>> I expect Simon won't like that it is another weak function.
>>
>> I did not find another way to implement the above use-cases. Maybe i 
>> missed something.
> 
> Based on the above, probably make a weak wrapper around the fpga_load() 
> call, make it call fpga_load() by default and override it in some board 
> specific manner if needed.

So instead of the implemented function in this patch, i add

__weak int fpga_load_wrapper(int devnum, const void *buf, size_t bsize,
			     bitstream_type bstype, int flags) {
	return fpga_load(devnum, buf, bsize, bstype, flags);
}

in the file common/spl/spl_fit.c and call this instead of fpga_load()?

This way only the logic for loading the fpga bitstream in the spl from a 
fit image would change, but not anywhere else (which is ok for me).

Regards,
Christian