Re: [RESEND][PATCH 1/3] meta: add new qemuarma9 machine definition

[Dmitry Eremin-Solenikov <dmitry_eremin@mentor.com>]

On 05/14/2015 05:37 PM, Bruce Ashfield wrote:
> On 2015-05-14 09:46 AM, Richard Purdie wrote:
>> On Wed, 2015-05-13 at 18:17 -0700, Andre McCurdy wrote:
>>> On Tue, May 12, 2015 at 7:47 AM, Martin Jansa
>>> <martin.jansa@gmail.com> wrote:
>>>> On Tue, May 12, 2015 at 03:25:43PM +0100, Burton, Ross wrote:
>>>>> On 11 May 2015 at 20:52, Dmitry Eremin-Solenikov
>>>>> <dmitry_eremin@mentor.com>
>>>>> wrote:
>>>>>
>>>>>> Currently qemuarm is limited to 256 Mb of RAM. Sometimes this is too
>>>>>> little to run necessary applications. Add a new arm configuration
>>>>>> based
>>>>>> on Versatile Express board, Cortex-A9 CPU, allowing up to 1Gb of RAM.
>>>>>>
>>>>>
>>>>> Not sure I'm keen on oe-core having two almost-identical qemuarm
>>>>> machines.
>>>>> Why not just change the qemuarm machine to use the A9?
>>>>
>>>> Then we should officially drop thumb1 support, because current qemuarm
>>>> builds are quite broken when thumb is enabled and dropping current
>>>> qemuarm or replacing it with A9 variant will prevent oe-core to be
>>>> testable on autobuilder. See
>>>> https://bugzilla.yoctoproject.org/show_bug.cgi?id=7717
>>>
>>> +1 for updating qemuarm to an ARMv7 CPU.
>>
>> One thing I did notice about the new proposed arm machine was the lack
>> of graphics support. We really do need a machine with graphics. If we
>> could get a machine which had graphics and more memory that would be
>> much more attractive to switch to.
>>
>> This also has implications on the kernel support (cc Bruce).
>
> I've been using the qemuarma9 machine in some different contexts for
> a while now, and in fact, there's a BSP definition in linux-yocto
> already for it.
>
> So from that point of view, the kernel impacts are understood.
>
> But not only does the qemuarma9 lack graphics, it also has issues
> with disk and USB, so generally it isn't as usable as the arm926
> qemu variant.

I ended up enabling virtio to get disc working in qemuarma9. Such setup 
is used in provided runqemu patches. However I did not include a patch 
to linux-yocto recipe/git tree.

>
> There are other options that have newer CPUs, or just changing the
> cpu .. but a wholesale switch to the "qemuarma9" machine tends to
> bring some new challenges.

Yes, that is why in the patches I proposed qemuarma9 as an alternative 
(rather then a replacement) to plain qemuarm.

-- 
With best wishes
Dmitry