Re: [Qemu-devel] [PATCH 0/6] Add i.MX6 (Single/Dual/Quad) support

[Jean-Christophe DUBOIS]

Le 02/02/2016 18:01, Peter Maydell a écrit :
> On 28 January 2016 at 19:22, Jean-Christophe DUBOIS <address@hidden> wrote:
> > Sabrelite uses uart2 for console but on qemu, this is uart1 that is wired to
> > the default stdout. Consequently, I changed stdout-path in "chosen" to
> > uart1.
> This I find a bit awkward: we'd like to get eventually to the point
> where you can run the stock device tree unedited. The other items
> on your list are just "we don't emulate something yet", so the path
> forward is to (eventually) emulate the missing things. But it's not
> clear to me what we need to do to be able to stop editing stdout-path
> in the future.
>
> Perhaps the answer is just to use QEMU command line arguments to make
> stdout be the uart2 rather than uart1?

I'll send a new version where the platform (sabrelite) can chose 
(through properties) which uart of the SOC (i.MX6) it wants to use as 
default output.

> > For now i.MX6 SOC code does not emulate SPI controller. During the boot
> > Linux was getting stuck trying to access a SPI device that is supposed to be
> > there. Therefore I disabled the SPI controller in the device tree.
> This is OK for now, though I guess it means the SPI controller is
> worth emulating to at least some extent.

I'll see what I can do next.

> > The sabrelite is supposed to have a bunch of push buttons (home, power,
> > back, vol up, vol down) wired to various GPIOs. I guess these buttons might
> > have pull up or pull down resistors on the real hardware but obviously on
> > qemu we have no such things. As a results the GPIOs were triggering a lot of
> > interrupts for nothing. So I commented out the GPIO sections were the
> > buttons were defined.
> This is OK for now, though it would be nice to wire all the GPIOs to 0 or
> something if that helps avoid the problem without editing the DT.

Ditto.

> thanks
> --- PMM