Re: [Qemu-arm] Use of -machine when running via qemu-system-arm

[Ajay Garg]

Hi Peter.

The link is pretty good, just that I am a complete noob.

Maybe a more concrete example on the following, clearly specifying why
things work on x86 without the need of -machine flag, will make things
crystal clear :

Because ARM systems differ so much and in fundamental ways, typically
operating system or firmware images intended to run on one machine
will not run at all on any other. This is often surprising for new
users who are used to the x86 world where every system looks like a
standard PC. (Once the kernel has booted, most userspace software
cares much less about the detail of the hardware.)


Sorry again for my zero knowledge on the ARM world.




On Mon, Apr 9, 2018 at 7:31 PM, Peter Maydell <address@hidden> wrote:
> On 9 April 2018 at 14:43, Ajay Garg <address@hidden> wrote:
>> On Mon, Apr 9, 2018 at 7:08 PM, Peter Maydell <address@hidden> wrote:
>>> On 9 April 2018 at 14:35, Ajay Garg <address@hidden> wrote:
>>>> Hi All.
>>>>
>>>> Not sure if this is purely an ARM-related question, but I will be
>>>> grateful if someone could point to some literature that explains what
>>>> difference choosing a  machine makes (when we don't need to have any
>>>> such flag for qemu-system-i386 or qemu-system-x86_64).
>>>
>>> Hi; this is a pretty common question, which we talk about on our
>>> wiki page here:
>>>  https://wiki.qemu.org/Documentation/Platforms/ARM
>>
>> Yep, had already been through it :)
>>
>>>
>>> The underlying reason why you need this on Arm but not on x86
>>> is that for x86 every single piece of x86 hardware is pretty
>>> much identical. For Arm (as part of its history in the embedded
>>> space) the general rule is that every board is different.
>>
>> Yep, perhaps I am needing a more layman-kinda example-cum-explanation
>> for this, so would be grateful for some help in this regard.
>
> Well, the wiki text is the best explanation I have; perhaps
> you could suggest what part of it is confusing, and we could
> improve it?
>
> thanks
> -- PMM



-- 
Regards,
Ajay