drm/xe/pf: Create separate debugfs tree for SR-IOV files

Currently we expose debugfs files related to SR-IOV functions
together with other native files, but that approach will not
scale well as we plan to add more attributes and also expose
some of them on the per-tile basis.

Start building separate tree for SR-IOV specific debugfs files
where we can replicate similar files per every SR-IOV function:

   /sys/kernel/debug/dri/BDF/
   ├── sriov
   │   ├── pf
   │   │   ├── tile0
   │   │   │   ├── gt0
   │   │   │   ├── gt1
   │   │   │   :
   │   │   ├── tile1
   │   │   :
   │   ├── vf1
   │   │   ├── tile0
   │   │   │   ├── gt0
   │   │   │   ├── gt1
   │   │   │   :
   │   │   :
   │   ├── vf2
   │   ├── ...

We will populate this new tree in upcoming patches.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://lore.kernel.org/r/20250928140029.198847-3-michal.wajdeczko@intel.com

1 files changed, 49 insertions, 9 deletions

diff --git a/drivers/gpu/drm/xe/xe_sriov_pf_debugfs.c b/drivers/gpu/drm/xe/xe_sriov_pf_debugfs.c
index 2a1316048439..37cc3a297667 100644
--- a/drivers/gpu/drm/xe/xe_sriov_pf_debugfs.c
+++ b/drivers/gpu/drm/xe/xe_sriov_pf_debugfs.c
@@ -9,7 +9,9 @@
 #include "xe_device_types.h"
 #include "xe_sriov_pf.h"
 #include "xe_sriov_pf_debugfs.h"
+#include "xe_sriov_pf_helpers.h"
 #include "xe_sriov_pf_service.h"
+#include "xe_sriov_printk.h"
 
 static int simple_show(struct seq_file *m, void *data)
 {
@@ -28,27 +30,65 @@ static const struct drm_info_list debugfs_list[] = {
 	{ .name = "versions", .show = simple_show, .data = xe_sriov_pf_service_print_versions },
 };
 
+static void pf_populate_pf(struct xe_device *xe, struct dentry *pfdent)
+{
+	struct drm_minor *minor = xe->drm.primary;
+
+	drm_debugfs_create_files(debugfs_list, ARRAY_SIZE(debugfs_list), pfdent, minor);
+}
+
 /**
  * xe_sriov_pf_debugfs_register - Register PF debugfs attributes.
  * @xe: the &xe_device
  * @root: the root &dentry
  *
- * Prepare debugfs attributes exposed by the PF.
+ * Create separate directory that will contain all SR-IOV related files,
+ * organized per each SR-IOV function (PF, VF1, VF2, ..., VFn).
  */
 void xe_sriov_pf_debugfs_register(struct xe_device *xe, struct dentry *root)
 {
-	struct drm_minor *minor = xe->drm.primary;
-	struct dentry *parent;
+	int totalvfs = xe_sriov_pf_get_totalvfs(xe);
+	struct dentry *pfdent;
+	struct dentry *vfdent;
+	struct dentry *dent;
+	char vfname[16]; /* should be more than enough for "vf%u\0" and VFID(UINT_MAX) */
+	unsigned int n;
 
 	/*
-	 *      /sys/kernel/debug/dri/0/
-	 *      ├── pf
+	 *      /sys/kernel/debug/dri/BDF/
+	 *      ├── sriov		# d_inode->i_private = (xe_device*)
 	 *      │   ├── ...
 	 */
-	parent = debugfs_create_dir("pf", root);
-	if (IS_ERR(parent))
+	dent = debugfs_create_dir("sriov", root);
+	if (IS_ERR(dent))
+		return;
+	dent->d_inode->i_private = xe;
+
+	/*
+	 *      /sys/kernel/debug/dri/BDF/
+	 *      ├── sriov		# d_inode->i_private = (xe_device*)
+	 *      │   ├── pf		# d_inode->i_private = (xe_device*)
+	 *      │   │   ├── ...
+	 */
+	pfdent = debugfs_create_dir("pf", dent);
+	if (IS_ERR(pfdent))
 		return;
-	parent->d_inode->i_private = xe;
+	pfdent->d_inode->i_private = xe;
+
+	pf_populate_pf(xe, pfdent);
 
-	drm_debugfs_create_files(debugfs_list, ARRAY_SIZE(debugfs_list), parent, minor);
+	/*
+	 *      /sys/kernel/debug/dri/BDF/
+	 *      ├── sriov		# d_inode->i_private = (xe_device*)
+	 *      │   ├── vf1		# d_inode->i_private = VFID(1)
+	 *      │   ├── vf2		# d_inode->i_private = VFID(2)
+	 *      │   ├── ...
+	 */
+	for (n = 1; n <= totalvfs; n++) {
+		snprintf(vfname, sizeof(vfname), "vf%u", VFID(n));
+		vfdent = debugfs_create_dir(vfname, dent);
+		if (IS_ERR(vfdent))
+			return;
+		vfdent->d_inode->i_private = (void *)(uintptr_t)VFID(n);
+	}
 }