[Intel-gfx] [PATCH 04/10] drm/i915: fix false positive "Unclaimed write" messages

[Damien Lespiau]

On Tue, Nov 20, 2012 at 7:10 PM, Paulo Zanoni <przanoni at gmail.com> wrote:
> Hi
>
> 2012/11/20 Damien Lespiau <damien.lespiau at intel.com>:
>>> +       if (IS_HASWELL(dev_priv->dev) && (I915_READ_NOTRACE(GEN7_ERR_INT) & ERR_INT_MMIO_UNCLAIMED)) { \
>>> +               DRM_ERROR("Unknown unclaimed register before writing to %x\n", reg); \
>>> +               I915_WRITE_NOTRACE(GEN7_ERR_INT, ERR_INT_MMIO_UNCLAIMED); \
>>> +       } \
>>
>> Do we really have to DRM_ERROR here? this bit being set seems to be
>> beyond things we can fix (BIOS leaving that behind?)
>
> If we do I915_WRITE_NOTRACE or I915_READ_NOTRACE to a register that
> does not exist I believe the unclaimed bit will be set.

Yup, that looks true, I guess that if we're seeing that BIOSes leave
that behind and generate a false positive we can write that bit when
cleaning up after the BIOS anyway.

Reviewed-by: Damien Lespiau <damien.lespiau at intel.com>

-- 
Damien