1 // SPDX-License-Identifier: MIT
2 /*
3 * Copyright © 2022 Intel Corporation
4 */
5
6 #include <drm/drm_device.h>
7 #include <linux/device.h>
8 #include <linux/kobject.h>
9 #include <linux/printk.h>
10 #include <linux/sysfs.h>
11
12 #include "i915_drv.h"
13 #include "i915_sysfs.h"
14 #include "intel_gt.h"
15 #include "intel_gt_sysfs.h"
16 #include "intel_gt_sysfs_pm.h"
17 #include "intel_gt_types.h"
18 #include "intel_rc6.h"
19
is_object_gt(struct kobject * kobj)20 bool is_object_gt(struct kobject *kobj)
21 {
22 return !strncmp(kobj->name, "gt", 2);
23 }
24
intel_gt_sysfs_get_drvdata(struct kobject * kobj,const char * name)25 struct intel_gt *intel_gt_sysfs_get_drvdata(struct kobject *kobj,
26 const char *name)
27 {
28 /*
29 * We are interested at knowing from where the interface
30 * has been called, whether it's called from gt/ or from
31 * the parent directory.
32 * From the interface position it depends also the value of
33 * the private data.
34 * If the interface is called from gt/ then private data is
35 * of the "struct intel_gt *" type, otherwise it's * a
36 * "struct drm_i915_private *" type.
37 */
38 if (!is_object_gt(kobj)) {
39 struct device *dev = kobj_to_dev(kobj);
40 struct drm_i915_private *i915 = kdev_minor_to_i915(dev);
41
42 return to_gt(i915);
43 }
44
45 return kobj_to_gt(kobj);
46 }
47
gt_get_parent_obj(struct intel_gt * gt)48 static struct kobject *gt_get_parent_obj(struct intel_gt *gt)
49 {
50 return >->i915->drm.primary->kdev->kobj;
51 }
52
id_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)53 static ssize_t id_show(struct kobject *kobj,
54 struct kobj_attribute *attr,
55 char *buf)
56 {
57 struct intel_gt *gt = intel_gt_sysfs_get_drvdata(kobj, attr->attr.name);
58
59 return sysfs_emit(buf, "%u\n", gt->info.id);
60 }
61 static struct kobj_attribute attr_id = __ATTR_RO(id);
62
63 static struct attribute *id_attrs[] = {
64 &attr_id.attr,
65 NULL,
66 };
67 ATTRIBUTE_GROUPS(id);
68
69 /* A kobject needs a release() method even if it does nothing */
kobj_gt_release(struct kobject * kobj)70 static void kobj_gt_release(struct kobject *kobj)
71 {
72 }
73
74 static struct kobj_type kobj_gt_type = {
75 .release = kobj_gt_release,
76 .sysfs_ops = &kobj_sysfs_ops,
77 .default_groups = id_groups,
78 };
79
intel_gt_sysfs_register(struct intel_gt * gt)80 void intel_gt_sysfs_register(struct intel_gt *gt)
81 {
82 /*
83 * We need to make things right with the
84 * ABI compatibility. The files were originally
85 * generated under the parent directory.
86 *
87 * We generate the files only for gt 0
88 * to avoid duplicates.
89 */
90 if (gt_is_root(gt))
91 intel_gt_sysfs_pm_init(gt, gt_get_parent_obj(gt));
92
93 /* init and xfer ownership to sysfs tree */
94 if (kobject_init_and_add(>->sysfs_gt, &kobj_gt_type,
95 gt->i915->sysfs_gt, "gt%d", gt->info.id))
96 goto exit_fail;
97
98 gt->sysfs_defaults = kobject_create_and_add(".defaults", >->sysfs_gt);
99 if (!gt->sysfs_defaults)
100 goto exit_fail;
101
102 intel_gt_sysfs_pm_init(gt, >->sysfs_gt);
103
104 return;
105
106 exit_fail:
107 kobject_put(>->sysfs_gt);
108 drm_warn(>->i915->drm,
109 "failed to initialize gt%d sysfs root\n", gt->info.id);
110 }
111
intel_gt_sysfs_unregister(struct intel_gt * gt)112 void intel_gt_sysfs_unregister(struct intel_gt *gt)
113 {
114 kobject_put(gt->sysfs_defaults);
115 kobject_put(>->sysfs_gt);
116 }
117