Re: [Qemu-trivial] [PATCH V2 1/2] ARM: PL061: Clear PL061 device state after reset

[Peter Maydell <peter.maydell@linaro.org>]

On 16 February 2016 at 14:35, Peter Maydell <peter.maydell@linaro.org> wrote:
> On 1 February 2016 at 20:49, Wei Huang <wei@redhat.com> wrote:
>> Current QEMU doesn't clear PL061 state after reset. This causes a
>> weird issue with guest reboot via GPIO. Here is the device state
>> description with two reboot requests:

>
> These reset values are all OK...
>
>> +
>> +static void pl061_state_reset(DeviceState *dev)
>> +{
>> +    PL061State *s = PL061(dev);
>> +
>> +    pl061_reset(s);
>>  }
>
> ...but you don't need to have this wrapper function.
> You can just do the reset in a function called pl061_reset()
> with the function signature we need for dc->reset.
> The only place that currently calls the existing pl061_reset()
> is the device's init function, and you can delete that call
> because the Device framework automatically calls the dc->reset
> function after device initialization.

I know this patch doesn't (by itself) fix the issues with guest
reboot, but I think it is worth having anyway because not resetting
the PL061 state is a genuine bug. Can you do a v3 and resend, please?

PS: please could you include a cover letter email next time round,
since this is a multi patch series?

Side note: half our "PL061" behaviour is actually specific
to the TI variant in the Luminary, and for our plain old PL061
we ought to restrict access to the registers that are Stellaris
only. But that's a different bug and not a very major one.

thanks
-- PMM