drm/xe/pf: Expose SR-IOV VFs configuration over debugfs

We already have functions to configure VF resources and to print
actual provisioning details. Expose this functionality in debugfs
to allow experiment with different settings or inspect details in
case of unexpected issues with the provisioning.

As debugfs attributes are per-VF, we use parent d_inode->i_private
to store VFID, similarly how we did for per-GT attributes.
Reviewed-by: Piotr Piórkowski <piotr.piorkowski@intel.com>
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240423131244.2045-2-michal.wajdeczko@intel.com

drivers/gpu/drm/xe/Makefile

@@ -163,6 +163,7 @@ xe-$(CONFIG_PCI_IOV) += \
 	xe_gt_sriov_pf.o \
 	xe_gt_sriov_pf_config.o \
 	xe_gt_sriov_pf_control.o \
+	xe_gt_sriov_pf_debugfs.o \
 	xe_gt_sriov_pf_policy.o \
 	xe_gt_sriov_pf_service.o \
 	xe_lmtt.o \

drivers/gpu/drm/xe/xe_gt_debugfs.c

@@ -13,6 +13,7 @@
 #include "xe_ggtt.h"
 #include "xe_gt.h"
 #include "xe_gt_mcr.h"
+#include "xe_gt_sriov_pf_debugfs.h"
 #include "xe_gt_topology.h"
 #include "xe_hw_engine.h"
 #include "xe_lrc.h"
@@ -21,6 +22,7 @@
 #include "xe_pm.h"
 #include "xe_reg_sr.h"
 #include "xe_reg_whitelist.h"
+#include "xe_sriov.h"
 #include "xe_uc_debugfs.h"
 #include "xe_wa.h"
 
@@ -288,4 +290,7 @@ void xe_gt_debugfs_register(struct xe_gt *gt)
 				 root, minor);
 
 	xe_uc_debugfs_register(&gt->uc, root);
+
+	if (IS_SRIOV_PF(xe))
+		xe_gt_sriov_pf_debugfs_register(gt, root);
 }

drivers/gpu/drm/xe/xe_gt_sriov_pf_debugfs.c

+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2023-2024 Intel Corporation
+ */
+
+#include <linux/debugfs.h>
+
+#include <drm/drm_print.h>
+#include <drm/drm_debugfs.h>
+
+#include "xe_bo.h"
+#include "xe_debugfs.h"
+#include "xe_device.h"
+#include "xe_gt.h"
+#include "xe_gt_debugfs.h"
+#include "xe_gt_sriov_pf_config.h"
+#include "xe_gt_sriov_pf_debugfs.h"
+#include "xe_gt_sriov_pf_helpers.h"
+#include "xe_pm.h"
+
+/*
+ *      /sys/kernel/debug/dri/0/
+ *      ├── gt0		# d_inode->i_private = gt
+ *      │   ├── pf	# d_inode->i_private = gt
+ *      │   ├── vf1	# d_inode->i_private = VFID(1)
+ *      :   :
+ *      │   ├── vfN	# d_inode->i_private = VFID(N)
+ */
+
+static void *extract_priv(struct dentry *d)
+{
+	return d->d_inode->i_private;
+}
+
+static struct xe_gt *extract_gt(struct dentry *d)
+{
+	return extract_priv(d->d_parent);
+}
+
+static unsigned int extract_vfid(struct dentry *d)
+{
+	return extract_priv(d) == extract_gt(d) ? PFID : (uintptr_t)extract_priv(d);
+}
+
+/*
+ *      /sys/kernel/debug/dri/0/
+ *      ├── gt0
+ *      │   ├── pf
+ *      │   │   ├── ggtt_available
+ *      │   │   ├── ggtt_provisioned
+ *      │   │   ├── contexts_provisioned
+ *      │   │   ├── doorbells_provisioned
+ */
+
+static const struct drm_info_list pf_info[] = {
+	{
+		"ggtt_available",
+		.show = xe_gt_debugfs_simple_show,
+		.data = xe_gt_sriov_pf_config_print_available_ggtt,
+	},
+	{
+		"ggtt_provisioned",
+		.show = xe_gt_debugfs_simple_show,
+		.data = xe_gt_sriov_pf_config_print_ggtt,
+	},
+	{
+		"contexts_provisioned",
+		.show = xe_gt_debugfs_simple_show,
+		.data = xe_gt_sriov_pf_config_print_ctxs,
+	},
+	{
+		"doorbells_provisioned",
+		.show = xe_gt_debugfs_simple_show,
+		.data = xe_gt_sriov_pf_config_print_dbs,
+	},
+};
+
+/*
+ *      /sys/kernel/debug/dri/0/
+ *      ├── gt0
+ *      │   ├── pf
+ *      │   │   ├── ggtt_spare
+ *      │   │   ├── lmem_spare
+ *      │   │   ├── doorbells_spare
+ *      │   │   ├── contexts_spare
+ *      │   │   ├── exec_quantum_ms
+ *      │   │   ├── preempt_timeout_us
+ *      │   ├── vf1
+ *      │   │   ├── ggtt_quota
+ *      │   │   ├── lmem_quota
+ *      │   │   ├── doorbells_quota
+ *      │   │   ├── contexts_quota
+ *      │   │   ├── exec_quantum_ms
+ *      │   │   ├── preempt_timeout_us
+ */
+
+#define DEFINE_SRIOV_GT_CONFIG_DEBUGFS_ATTRIBUTE(CONFIG, TYPE, FORMAT)		\
+										\
+static int CONFIG##_set(void *data, u64 val)					\
+{										\
+	struct xe_gt *gt = extract_gt(data);					\
+	unsigned int vfid = extract_vfid(data);					\
+	struct xe_device *xe = gt_to_xe(gt);					\
+	int err;								\
+										\
+	if (val > (TYPE)~0ull)							\
+		return -EOVERFLOW;						\
+										\
+	xe_pm_runtime_get(xe);							\
+	err = xe_gt_sriov_pf_config_set_##CONFIG(gt, vfid, val);		\
+	xe_pm_runtime_put(xe);							\
+										\
+	return err;								\
+}										\
+										\
+static int CONFIG##_get(void *data, u64 *val)					\
+{										\
+	struct xe_gt *gt = extract_gt(data);					\
+	unsigned int vfid = extract_vfid(data);					\
+										\
+	*val = xe_gt_sriov_pf_config_get_##CONFIG(gt, vfid);			\
+	return 0;								\
+}										\
+										\
+DEFINE_DEBUGFS_ATTRIBUTE(CONFIG##_fops, CONFIG##_get, CONFIG##_set, FORMAT)
+
+DEFINE_SRIOV_GT_CONFIG_DEBUGFS_ATTRIBUTE(ggtt, u64, "%llu\n");
+DEFINE_SRIOV_GT_CONFIG_DEBUGFS_ATTRIBUTE(lmem, u64, "%llu\n");
+DEFINE_SRIOV_GT_CONFIG_DEBUGFS_ATTRIBUTE(ctxs, u32, "%llu\n");
+DEFINE_SRIOV_GT_CONFIG_DEBUGFS_ATTRIBUTE(dbs, u32, "%llu\n");
+DEFINE_SRIOV_GT_CONFIG_DEBUGFS_ATTRIBUTE(exec_quantum, u32, "%llu\n");
+DEFINE_SRIOV_GT_CONFIG_DEBUGFS_ATTRIBUTE(preempt_timeout, u32, "%llu\n");
+
+static void pf_add_config_attrs(struct xe_gt *gt, struct dentry *parent, unsigned int vfid)
+{
+	xe_gt_assert(gt, gt == extract_gt(parent));
+	xe_gt_assert(gt, vfid == extract_vfid(parent));
+
+	if (!xe_gt_is_media_type(gt)) {
+		debugfs_create_file_unsafe(vfid ? "ggtt_quota" : "ggtt_spare",
+					   0644, parent, parent, &ggtt_fops);
+		if (IS_DGFX(gt_to_xe(gt)))
+			debugfs_create_file_unsafe(vfid ? "lmem_quota" : "lmem_spare",
+						   0644, parent, parent, &lmem_fops);
+	}
+	debugfs_create_file_unsafe(vfid ? "doorbells_quota" : "doorbells_spare",
+				   0644, parent, parent, &dbs_fops);
+	debugfs_create_file_unsafe(vfid ? "contexts_quota" : "contexts_spare",
+				   0644, parent, parent, &ctxs_fops);
+	debugfs_create_file_unsafe("exec_quantum_ms", 0644, parent, parent,
+				   &exec_quantum_fops);
+	debugfs_create_file_unsafe("preempt_timeout_us", 0644, parent, parent,
+				   &preempt_timeout_fops);
+}
+
+/**
+ * xe_gt_sriov_pf_debugfs_register - Register SR-IOV PF specific entries in GT debugfs.
+ * @gt: the &xe_gt to register
+ * @root: the &dentry that represents the GT directory
+ *
+ * Register SR-IOV PF entries that are GT related and must be shown under GT debugfs.
+ */
+void xe_gt_sriov_pf_debugfs_register(struct xe_gt *gt, struct dentry *root)
+{
+	struct xe_device *xe = gt_to_xe(gt);
+	struct drm_minor *minor = xe->drm.primary;
+	int n, totalvfs = xe_sriov_pf_get_totalvfs(xe);
+	struct dentry *pfdentry;
+	struct dentry *vfdentry;
+	char buf[14]; /* should be enough up to "vf%u\0" for 2^32 - 1 */
+
+	xe_gt_assert(gt, IS_SRIOV_PF(xe));
+	xe_gt_assert(gt, root->d_inode->i_private == gt);
+
+	/*
+	 *      /sys/kernel/debug/dri/0/
+	 *      ├── gt0
+	 *      │   ├── pf
+	 */
+	pfdentry = debugfs_create_dir("pf", root);
+	if (IS_ERR(pfdentry))
+		return;
+	pfdentry->d_inode->i_private = gt;
+
+	drm_debugfs_create_files(pf_info, ARRAY_SIZE(pf_info), pfdentry, minor);
+	pf_add_config_attrs(gt, pfdentry, PFID);
+
+	for (n = 1; n <= totalvfs; n++) {
+		/*
+		 *      /sys/kernel/debug/dri/0/
+		 *      ├── gt0
+		 *      │   ├── vf1
+		 *      │   ├── vf2
+		 */
+		snprintf(buf, sizeof(buf), "vf%u", n);
+		vfdentry = debugfs_create_dir(buf, root);
+		if (IS_ERR(vfdentry))
+			break;
+		vfdentry->d_inode->i_private = (void *)(uintptr_t)n;
+
+		pf_add_config_attrs(gt, vfdentry, VFID(n));
+	}
+}

drivers/gpu/drm/xe/xe_gt_sriov_pf_debugfs.h

+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2023-2024 Intel Corporation
+ */
+
+#ifndef _XE_GT_SRIOV_PF_DEBUGFS_H_
+#define _XE_GT_SRIOV_PF_DEBUGFS_H_
+
+struct xe_gt;
+struct dentry;
+
+#ifdef CONFIG_PCI_IOV
+void xe_gt_sriov_pf_debugfs_register(struct xe_gt *gt, struct dentry *root);
+#else
+static inline void xe_gt_sriov_pf_debugfs_register(struct xe_gt *gt, struct dentry *root) { }
+#endif
+
+#endif