drm/xe: Update runtime detection of has_flat_ccs

It's confusing to have a *set* function that actually probes the
hardware rather than receiving a parameter. Rename it to *probe* along
with prefix removal and comment in the relevant places that the
has_flat_ccs flag may be overridden in runtime.

While at it, fix the mixed declaration of struct xe_gt.

Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Reviewed-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240904162238.2831202-2-lucas.demarchi@intel.com
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>

drivers/gpu/drm/xe/xe_device.c

@@ -588,15 +588,17 @@ int xe_device_probe_early(struct xe_device *xe)
 	return 0;
 }
 
-static int xe_device_set_has_flat_ccs(struct  xe_device *xe)
+static int probe_has_flat_ccs(struct xe_device *xe)
 {
+	struct xe_gt *gt;
 	u32 reg;
 	int err;
 
+	/* Always enabled/disabled, no runtime check to do */
 	if (GRAPHICS_VER(xe) < 20 || !xe->info.has_flat_ccs)
 		return 0;
 
-	struct xe_gt *gt = xe_root_mmio_gt(xe);
+	gt = xe_root_mmio_gt(xe);
 
 	err = xe_force_wake_get(gt_to_fw(gt), XE_FW_GT);
 	if (err)
@@ -688,7 +690,7 @@ int xe_device_probe(struct xe_device *xe)
 	if (err)
 		goto err;
 
-	err = xe_device_set_has_flat_ccs(xe);
+	err = probe_has_flat_ccs(xe);
 	if (err)
 		goto err;
 

drivers/gpu/drm/xe/xe_pci.c

@@ -679,7 +679,10 @@ static int xe_info_init(struct xe_device *xe,
 	xe->info.has_atomic_enable_pte_bit = graphics_desc->has_atomic_enable_pte_bit;
 	if (xe->info.platform != XE_PVC)
 		xe->info.has_device_atomics_on_smem = 1;
+
+	/* Runtime detection may change this later */
 	xe->info.has_flat_ccs = graphics_desc->has_flat_ccs;
+
 	xe->info.has_range_tlb_invalidation = graphics_desc->has_range_tlb_invalidation;
 	xe->info.has_usm = graphics_desc->has_usm;