drm/xe/vram: Use pci_rebar_get_max_size()

Use pci_rebar_get_max_size() from PCI core in resize_vram_bar() to simplify
code.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patch.msgid.link/20251113180053.27944-10-ilpo.jarvinen@linux.intel.com

Author: ij-intel

drivers/gpu/drm/xe/xe_vram.c

@@ -53,16 +53,11 @@ static void resize_vram_bar(struct xe_device *xe)
 	resource_size_t current_size;
 	resource_size_t rebar_size;
 	struct resource *root_res;
-	u32 bar_size_mask;
+	int max_size, i;
 	u32 pci_cmd;
-	int i;
 
 	/* gather some relevant info */
 	current_size = pci_resource_len(pdev, LMEM_BAR);
-	bar_size_mask = pci_rebar_get_possible_sizes(pdev, LMEM_BAR);
-
-	if (!bar_size_mask)
-		return;
 
 	if (force_vram_bar_size < 0)
 		return;
@@ -76,15 +71,19 @@ static void resize_vram_bar(struct xe_device *xe)
 			drm_info(&xe->drm,
 				 "Requested size: %lluMiB is not supported by rebar sizes: 0x%x. Leaving default: %lluMiB\n",
 				 (u64)pci_rebar_size_to_bytes(rebar_size) >> 20,
-				 bar_size_mask, (u64)current_size >> 20);
+				 pci_rebar_get_possible_sizes(pdev, LMEM_BAR),
+				 (u64)current_size >> 20);
 			return;
 		}
 
 		rebar_size = pci_rebar_size_to_bytes(rebar_size);
 		if (rebar_size == current_size)
 			return;
 	} else {
-		rebar_size = pci_rebar_size_to_bytes(__fls(bar_size_mask));
+		max_size = pci_rebar_get_max_size(pdev, LMEM_BAR);
+		if (max_size < 0)
+			return;
+		rebar_size = pci_rebar_size_to_bytes(max_size);
 
 		/* only resize if larger than current */
 		if (rebar_size <= current_size)