Re: [Qemu-discuss] [OpenBIOS] Qemu-system-sparc: What would I need to change to add functionality to save the nvram content between boots ?

[Laurent Vivier]

Le 11/09/2015 23:07, Programmingkid a écrit :
> 
> On Sep 11, 2015, at 4:09 PM, Laurent Vivier wrote:
> 
>>
>>
>> Le 11/09/2015 20:01, Programmingkid a écrit :
>>>
>>> On Sep 11, 2015, at 12:00 PM, address@hidden
>>> <mailto:address@hidden> wrote:
>>>
>>>> On 10/09/2015 8:58 AM, Maximilian H. wrote:
>>>>> Hello,
>>>>>
>>>>> I was looking into what parts would need change to save and restore the
>>>>> nvram content for the qemu-system-sparc vm between boots.
>>>>>
>>>>> I see the code in hw/timer/m48t59.c that implements the nvram.
>>>>>
>>>>> So some questions arise, and before I spend too much time poking around
>>>>> the still unknown code, I'd thought I ask first.
>>>>>
>>>>> 1. Command line processing starts in vl.c in the main fct there ? Can I
>>>>> add a command line argument there, say "-sparcnvram" ?
>>>>>
>>>>> 2. In hw/timer/m48t59.c has no functionality that I see from having a
>>>>> look at it (not in depth) to save or restore the nvram's contents for
>>>>> sparc. Is there a general facility that qemu has that provides such a
>>>>> functionality - i.e. is there a general qemu save and restore framework ?
>>>>>
>>>>> 3. Is there an example somebody could point me to that implements
>>>>> something similar ? Imitation is the sincerest of flattery ....
>>>>>
>>>>> 4. All the alarm and watchdog functionality that the m48t08 provides, is
>>>>> that used on sparc too ?
>>>>>
>>>>> 5. Besides what is in
>>>>> http://wiki.qemu.org/Documentation/GettingStartedDevelopers, is there
>>>>> some qemu coding documentation to make it faster for somebody unfamilar
>>>>> with qemu's code like me to be able to implement something ? I'd like to
>>>>> spend a few evenings on this, produce a patch and move on.
>>>>>
>>>>> Thanks
>>>>> BR
>>>>> Max.
>>>>
>>>
>>> This sounds like a good idea. Having OpenBIOS settings actually be saved
>>> between boots
>>> would make things more real. 
>>>
>>> Mark, do you think it is possible for a QEMU command line option to
>>> actually load the
>>> saved OpenBIOS settings from a file and restore them into memory? I'm
>>> thinking something
>>> along the lines of -prom-memory <file name>. 
>>
>> Nostalgia: a seven years old thread, out of date now:
>>
>> https://lists.gnu.org/archive/html/qemu-devel/2008-05/msg00002.html
>>
>>>
>>> Max, there is a project that you should probably look at called
>>> OpenBIOS. It implements
>>> an implementation of Open Firmware. Here is where more info can be
>>> found: http://www.openfirmware.info/Welcome_to_OpenBIOS. If you do want
>>> to implement this feature,
>>> it would help to know how the BIOS is implemented. 
>>
>> Laurent
> 
> Could you send the patch please?
> 

The patch is attached to the mail in the thread. Anyway, I don't think
it applies now.

Laurent