Re: [PATCH v4] drm/xe: use entry_dump callbacks for xe2+ PAT dumps

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

On Fri, Jan 30, 2026 at 05:53:49PM +0000, Xin Wang wrote:
> Move xe2+ PAT entry printing into the entry_dump op so platform
> specific logic stays localized, simplifying future maintenance.
> 
> v2:
>  - Do not null xe->pat.ops for VFs.
>  - Skip PAT init and dump on VFs (-EOPNOTSUPP), avoiding NULL ops use.
> 
> v3:
>  - fixed typo
> 
> v4: (Matt)
>  - Switch xe2_dump() to use the new ops->entry_dump() vfunc.
>  - Remove xe3p_xpc_dump() and reuse the common xe2_dump() for Xe3p XPC.
>  - This also fixes Xe3p_HPM media PAT dumping by using the proper
> non-MCR access for the PAT register range (bspec 76445).
> 
> Cc: Matt Roper <matthew.d.roper@intel.com>
> Suggested-by: Brian Nguyen <brian3.nguyen@intel.com>
> Signed-off-by: Xin Wang <x.wang@intel.com>

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

> ---
>  drivers/gpu/drm/xe/xe_pat.c | 67 +++++++++----------------------------
>  1 file changed, 16 insertions(+), 51 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_pat.c b/drivers/gpu/drm/xe/xe_pat.c
> index 14d0dce5190a..2cd3fd1c3953 100644
> --- a/drivers/gpu/drm/xe/xe_pat.c
> +++ b/drivers/gpu/drm/xe/xe_pat.c
> @@ -88,6 +88,7 @@ struct xe_pat_ops {
>  	void (*program_media)(struct xe_gt *gt, const struct xe_pat_table_entry table[],
>  			      int n_entries);
>  	int (*dump)(struct xe_gt *gt, struct drm_printer *p);
> +	void (*entry_dump)(struct drm_printer *p, const char *label, u32 pat, bool rsvd);
>  };
>  
>  static const struct xe_pat_table_entry xelp_pat_table[] = {
> @@ -458,7 +459,7 @@ static int xe2_dump(struct xe_gt *gt, struct drm_printer *p)
>  			pat = xe_gt_mcr_unicast_read_any(gt, XE_REG_MCR(_PAT_INDEX(i)));
>  
>  		xe_pat_index_label(label, sizeof(label), i);
> -		xe2_pat_entry_dump(p, label, pat, !xe->pat.table[i].valid);
> +		xe->pat.ops->entry_dump(p, label, pat, !xe->pat.table[i].valid);
>  	}
>  
>  	/*
> @@ -471,7 +472,7 @@ static int xe2_dump(struct xe_gt *gt, struct drm_printer *p)
>  		pat = xe_gt_mcr_unicast_read_any(gt, XE_REG_MCR(_PAT_PTA));
>  
>  	drm_printf(p, "Page Table Access:\n");
> -	xe2_pat_entry_dump(p, "PTA_MODE", pat, false);
> +	xe->pat.ops->entry_dump(p, "PTA_MODE", pat, false);
>  
>  	return 0;
>  }
> @@ -480,44 +481,14 @@ static const struct xe_pat_ops xe2_pat_ops = {
>  	.program_graphics = program_pat_mcr,
>  	.program_media = program_pat,
>  	.dump = xe2_dump,
> +	.entry_dump = xe2_pat_entry_dump,
>  };
>  
> -static int xe3p_xpc_dump(struct xe_gt *gt, struct drm_printer *p)
> -{
> -	struct xe_device *xe = gt_to_xe(gt);
> -	u32 pat;
> -	int i;
> -	char label[PAT_LABEL_LEN];
> -
> -	CLASS(xe_force_wake, fw_ref)(gt_to_fw(gt), XE_FW_GT);
> -	if (!fw_ref.domains)
> -		return -ETIMEDOUT;
> -
> -	drm_printf(p, "PAT table: (* = reserved entry)\n");
> -
> -	for (i = 0; i < xe->pat.n_entries; i++) {
> -		pat = xe_gt_mcr_unicast_read_any(gt, XE_REG_MCR(_PAT_INDEX(i)));
> -
> -		xe_pat_index_label(label, sizeof(label), i);
> -		xe3p_xpc_pat_entry_dump(p, label, pat, !xe->pat.table[i].valid);
> -	}
> -
> -	/*
> -	 * Also print PTA_MODE, which describes how the hardware accesses
> -	 * PPGTT entries.
> -	 */
> -	pat = xe_gt_mcr_unicast_read_any(gt, XE_REG_MCR(_PAT_PTA));
> -
> -	drm_printf(p, "Page Table Access:\n");
> -	xe3p_xpc_pat_entry_dump(p, "PTA_MODE", pat, false);
> -
> -	return 0;
> -}
> -
>  static const struct xe_pat_ops xe3p_xpc_pat_ops = {
>  	.program_graphics = program_pat_mcr,
>  	.program_media = program_pat,
> -	.dump = xe3p_xpc_dump,
> +	.dump = xe2_dump,
> +	.entry_dump = xe3p_xpc_pat_entry_dump,
>  };
>  
>  void xe_pat_init_early(struct xe_device *xe)
> @@ -600,20 +571,17 @@ void xe_pat_init_early(struct xe_device *xe)
>  			GRAPHICS_VER(xe), GRAPHICS_VERx100(xe) % 100);
>  	}
>  
> -	/* VFs can't program nor dump PAT settings */
> -	if (IS_SRIOV_VF(xe))
> -		xe->pat.ops = NULL;
> -
> -	xe_assert(xe, !xe->pat.ops || xe->pat.ops->dump);
> -	xe_assert(xe, !xe->pat.ops || xe->pat.ops->program_graphics);
> -	xe_assert(xe, !xe->pat.ops || MEDIA_VER(xe) < 13 || xe->pat.ops->program_media);
> +	xe_assert(xe, xe->pat.ops->dump);
> +	xe_assert(xe, xe->pat.ops->program_graphics);
> +	xe_assert(xe, MEDIA_VER(xe) < 13 || xe->pat.ops->program_media);
> +	xe_assert(xe, GRAPHICS_VER(xe) < 20 || xe->pat.ops->entry_dump);
>  }
>  
>  void xe_pat_init(struct xe_gt *gt)
>  {
>  	struct xe_device *xe = gt_to_xe(gt);
>  
> -	if (!xe->pat.ops)
> +	if (IS_SRIOV_VF(xe))
>  		return;
>  
>  	if (xe_gt_is_media_type(gt))
> @@ -633,7 +601,7 @@ int xe_pat_dump(struct xe_gt *gt, struct drm_printer *p)
>  {
>  	struct xe_device *xe = gt_to_xe(gt);
>  
> -	if (!xe->pat.ops)
> +	if (IS_SRIOV_VF(xe))
>  		return -EOPNOTSUPP;
>  
>  	return xe->pat.ops->dump(gt, p);
> @@ -658,12 +626,9 @@ int xe_pat_dump_sw_config(struct xe_gt *gt, struct drm_printer *p)
>  	for (u32 i = 0; i < xe->pat.n_entries; i++) {
>  		u32 pat = xe->pat.table[i].value;
>  
> -		if (GRAPHICS_VERx100(xe) == 3511) {
> -			xe_pat_index_label(label, sizeof(label), i);
> -			xe3p_xpc_pat_entry_dump(p, label, pat, !xe->pat.table[i].valid);
> -		} else if (GRAPHICS_VER(xe) == 30 || GRAPHICS_VER(xe) == 20) {
> +		if (GRAPHICS_VER(xe) >= 20) {
>  			xe_pat_index_label(label, sizeof(label), i);
> -			xe2_pat_entry_dump(p, label, pat, !xe->pat.table[i].valid);
> +			xe->pat.ops->entry_dump(p, label, pat, !xe->pat.table[i].valid);
>  		} else if (xe->info.platform == XE_METEORLAKE) {
>  			xelpg_pat_entry_dump(p, i, pat);
>  		} else if (xe->info.platform == XE_PVC) {
> @@ -679,14 +644,14 @@ int xe_pat_dump_sw_config(struct xe_gt *gt, struct drm_printer *p)
>  		u32 pat = xe->pat.pat_pta->value;
>  
>  		drm_printf(p, "Page Table Access:\n");
> -		xe2_pat_entry_dump(p, "PTA_MODE", pat, false);
> +		xe->pat.ops->entry_dump(p, "PTA_MODE", pat, false);
>  	}
>  
>  	if (xe->pat.pat_ats) {
>  		u32 pat = xe->pat.pat_ats->value;
>  
>  		drm_printf(p, "PCIe ATS/PASID:\n");
> -		xe2_pat_entry_dump(p, "PAT_ATS ", pat, false);
> +		xe->pat.ops->entry_dump(p, "PAT_ATS ", pat, false);
>  	}
>  
>  	drm_printf(p, "Cache Level:\n");
> -- 
> 2.43.0
> 

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