[PATCH v3 09/12] drm/xe/pxp: Add API to mark a BO as using PXP

[Daniele Ceraolo Spurio]

On 11/22/2024 7:06 AM, Jani Nikula wrote:
> On Thu, 21 Nov 2024, Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com> wrote:
>> On 11/21/2024 12:03 PM, Jani Nikula wrote:
>>> On Thu, 21 Nov 2024, Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com> wrote:
>>>> On 11/21/2024 1:57 AM, Jani Nikula wrote:
>>>>> On Wed, 20 Nov 2024, Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com> wrote:
>>>>>> diff --git a/drivers/gpu/drm/xe/compat-i915-headers/pxp/intel_pxp.h b/drivers/gpu/drm/xe/compat-i915-headers/pxp/intel_pxp.h
>>>>>> index 419e8e926f00..533bc82255b6 100644
>>>>>> --- a/drivers/gpu/drm/xe/compat-i915-headers/pxp/intel_pxp.h
>>>>>> +++ b/drivers/gpu/drm/xe/compat-i915-headers/pxp/intel_pxp.h
>>>>>> @@ -9,6 +9,9 @@
>>>>>>     #include <linux/errno.h>
>>>>>>     #include <linux/types.h>
>>>>>>     
>>>>>> +#include "xe_bo.h"
>>>>>> +#include "xe_pxp.h"
>>>>>> +
>>>>> Can't have this. This will include xe_bo.h and xe_pxp.h from i915
>>>>> display.
>>>>>
>>>>> Basically you can't use gem_to_xe_bo() in static inlines in headers that
>>>>> get included to i915 display. It all needs to stay opaque.
>>>> Why would this be included to i915 display? This is the copy of the
>>>> header used for building the display code with Xe, i915 should use it's
>>>> own copy (i915/pxp/intel_pxp.h). Several other headers in the
>>>> compat-i915-headers subfolder include Xe headers. Or is the problem
>>>> specifically with the BO part of it? Because I can move the code to
>>>> xe_pxp.c, but I'd still have to include at least xe_pxp.h.
>>> With "i915 display", I refer to the display code that gets built for
>>> both i915 and xe. And regardless of which module the code is being built
>>> for, it should not include details like this. The goal is to make it
>>> more and more independent from the two, eventually spawning into a
>>> dedicated module. So we want to axe includes that lead from i915 display
>>> to either i915 or xe core headers.
>> Ok that makes sense, but I'm not sure if it can be easily avoided here.
>> The PXP key is managed outside of the display code, so we do need a
>> callback into Xe or i915 to get that info. The only way I can see that
>> being doable without the different headers is if we pass a function
>> pointer at display init time and keep that stored inside the
>> intel_display structure. That to me sounds like something that should be
>> introduced more structurally for multiple callbacks into i915/xe instead
>> of just for PXP, but I can do it if that's the preference.
> Why not make xe_pxp_key_check() accept struct drm_gem_object * instead
> of struct xe_bo *? Basically all the interfaces to/from display will
> need to use i915/xe independent types anyway.

I can do that, but I'd still need to include xe_pxp.h to bring in 
xe_pxp_key_check(), so there is still going to be an include that goes 
from display into Xe. If that's ok for now, I'll go that way.

Daniele

>
> See ad36a322619c ("drm/i915/display: convert skl_universal_plane.c to
> struct drm_gem_object") which converts i915 pxp. And i915 display gets
> to use either opaque types or generic drm types.
>
> BR,
> Jani.
>
>
>
>> thanks,
>> Daniele
>>
>>> BR,
>>> Jani.
>>>
>>>
>>>
>>>> Daniele
>>>>
>>>>> BR,
>>>>> Jani.
>>>>>
>>>>>>     struct drm_gem_object;
>>>>>>     struct xe_pxp;
>>>>>>     
>>>>>> @@ -16,7 +19,15 @@ static inline int intel_pxp_key_check(struct xe_pxp *pxp,
>>>>>>     				      struct drm_gem_object *obj,
>>>>>>     				      bool assign)
>>>>>>     {
>>>>>> -	return -ENODEV;
>>>>>> +	/*
>>>>>> +	 * The assign variable is used in i915 to assign the key to the BO at
>>>>>> +	 * first submission time. In Xe the key is instead assigned at BO
>>>>>> +	 * creation time, so the assign variable must always be false.
>>>>>> +	 */
>>>>>> +	if (assign)
>>>>>> +		return -EINVAL;
>>>>>> +
>>>>>> +	return xe_pxp_key_check(pxp, gem_to_xe_bo(obj));
>>>>>>     }
>>>>>>     
>>>>>>     #endif