Re: [PATCH 7/8] drm/xe/vf: Don't program PAT if VF

[Matt Roper <matthew.d.roper@intel.com>]

On Fri, Jan 12, 2024 at 04:26:48PM +0100, Michal Wajdeczko wrote:
> PAT programming can only be done by the PF driver.
> Besides VF drivers don't have access to control registers.
> 
> Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
> Cc: Matt Roper <matthew.d.roper@intel.com>

Reviewed-by: Matt Roper <matthew.d.roper@intel.com>

> ---
>  drivers/gpu/drm/xe/xe_pat.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/gpu/drm/xe/xe_pat.c b/drivers/gpu/drm/xe/xe_pat.c
> index 1ff6bc79e7d4..e148934d554b 100644
> --- a/drivers/gpu/drm/xe/xe_pat.c
> +++ b/drivers/gpu/drm/xe/xe_pat.c
> @@ -13,6 +13,7 @@
>  #include "xe_gt.h"
>  #include "xe_gt_mcr.h"
>  #include "xe_mmio.h"
> +#include "xe_sriov.h"
>  
>  #define _PAT_ATS				0x47fc
>  #define _PAT_INDEX(index)			_PICK_EVEN_2RANGES(index, 8, \
> @@ -433,6 +434,10 @@ void xe_pat_init_early(struct xe_device *xe)
>  		drm_err(&xe->drm, "Missing PAT table for platform with graphics version %d.%02d!\n",
>  			GRAPHICS_VER(xe), GRAPHICS_VERx100(xe) % 100);
>  	}
> +
> +	/* VFs can't program nor dump PAT settings */
> +	if (IS_SRIOV_VF(xe))
> +		xe->pat.ops = NULL;
>  }
>  
>  void xe_pat_init(struct xe_gt *gt)
> -- 
> 2.25.1
> 

-- 
Matt Roper
Graphics Software Engineer
Linux GPU Platform Enablement
Intel Corporation