Re: [PATCH v3 4/7] drm/xe/display: add generic __to_intel_display()

[Jani Nikula <jani.nikula@intel.com>]

On Wed, 17 Apr 2024, Jani Nikula <jani.nikula@intel.com> wrote:
> On Tue, 16 Apr 2024, Rodrigo Vivi <rodrigo.vivi@intel.com> wrote:
>> On Tue, Apr 09, 2024 at 03:26:46PM +0300, Jani Nikula wrote:
>>> Add generic __to_intel_display() macro that accepts either struct
>>> xe_device * or struct intel_display *. This is to be used for
>>> transitional stuff that eventually needs to be converted to use struct
>>> intel_display *, and therefore is not part of to_intel_display().
>>> 
>>> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
>>> ---
>>>  drivers/gpu/drm/xe/compat-i915-headers/i915_drv.h | 11 +++++++++++
>>>  1 file changed, 11 insertions(+)
>>> 
>>> diff --git a/drivers/gpu/drm/xe/compat-i915-headers/i915_drv.h b/drivers/gpu/drm/xe/compat-i915-headers/i915_drv.h
>>> index 2792a497257e..4448eda8b2a4 100644
>>> --- a/drivers/gpu/drm/xe/compat-i915-headers/i915_drv.h
>>> +++ b/drivers/gpu/drm/xe/compat-i915-headers/i915_drv.h
>>> @@ -29,6 +29,17 @@
>>>  #include "intel_runtime_pm.h"
>>>  #include <linux/pm_runtime.h>
>>>  
>>> +/*
>>> + * Transitional macro to optionally convert struct xe_device * to struct
>>> + * intel_display *, also accepting the latter.
>>> + */
>>> +#define __to_intel_display(p)						\
>>> +	_Generic(p,							\
>>> +		 const struct xe_device *: (&((const struct xe_device *)(p))->display), \
>>> +		 struct xe_device *: (&((struct xe_device *)(p))->display), \
>>> +		 const struct intel_display *: (p),			\
>>> +		 struct intel_display *: (p))
>>
>> hmmm... I thought that with our make magic we didn't need this.
>> but well, at least more awareness and trying to get rid of the make magic
>> earlier?
>
> It's needed because in i915 I wanted to put this in i915_drv.h to not
> create a extra dependency to/from i915_drv.h. I tried, it gets tricky.
> So weed another copy xe side.
>
> The make magic does convert all struct drm_i915_private to struct
> xe_device, so this could have struct drm_i915_private, but the other
> copy is not available here.

Okay, so in v4 I decided to shove the macro to a header, and this patch
and the duplication is no longer needed.

BR,
Jani.


>
> BR,
> Jani.
>
>>
>> Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
>>
>>> +
>>>  static inline struct drm_i915_private *to_i915(const struct drm_device *dev)
>>>  {
>>>  	return container_of(dev, struct drm_i915_private, drm);
>>> -- 
>>> 2.39.2
>>> 

-- 
Jani Nikula, Intel