Re: [PATCH] generic-loader: remove the ram_size limit when a loading binary file

[Philippe Mathieu-Daudé]

On 10/6/21 17:40, Alex Bennée wrote:
> 
> Damien Hedde <damien.hedde@greensocs.com> writes:
> 
>> On 10/6/21 13:49, Philippe Mathieu-Daudé wrote:
>>> On 10/6/21 13:37, Damien Hedde wrote:
>>>> Right now, we cannot load some binary file if it is bigger than the
>>>> machine's ram size. This limitation only occurs when loading a
>>>> binary file: we can load a corresponding elf file without this
>>>> limitation.
>>>>
>>>> This is an issue for machines that have small ram or do not use the
>>>> ram_size feature at all.
>>>>
>>>> Also get rid of "hw/boards.h" include, since we needed it only
>>>> to access `current_machine`.
>>>>
>>>> Fixes: e481a1f63c9 ("generic-loader: Add a generic loader")
>>>> Signed-off-by: Damien Hedde <damien.hedde@greensocs.com>
>>>> ---
>>>>
>>>> Hi Alistair,
>>>>
>>>> I found this while experimenting with a ram_size=0 machine.
>>
>>
>>
>>> Where are you loading your file?
>>>
>>
>> In a rom.
>>
>> The loader does not check at all that we are loading to the machine's
>> ram. It just check the size for the raw binary file format.
> 
> It does beg the question of why you don't just construct your ROM file
> with the image in place there? Is this just a development convenience?

generic-loader is designed from a CPU perspective, it uses the CPU AS
to load the image.

If your image is in ROM, I'm not sure this is the correct API. I'd try
to do this without considering any CPU in the picture. The rom_add_*()
API might be more appropriate.

My 2 cents anyway...