xref: /linux/drivers/gpu/drm/xe/xe_vram_freq.c (revision 1fd1dc41724319406b0aff221a352a400b0ddfc5)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2024 Intel Corporation
4  */
5 #include <linux/sysfs.h>
6 #include <drm/drm_managed.h>
7 
8 #include "xe_pcode.h"
9 #include "xe_pcode_api.h"
10 #include "xe_tile.h"
11 #include "xe_tile_sysfs.h"
12 #include "xe_vram_freq.h"
13 
14 /**
15  * DOC: Xe VRAM freq
16  *
17  * Provides sysfs entries for vram frequency in tile
18  *
19  * device/tile#/memory/freq0/max_freq - This is maximum frequency. This value is read-only as it
20  *					is the fixed fuse point P0. It is not the system
21  *					configuration.
22  * device/tile#/memory/freq0/min_freq - This is minimum frequency. This value is read-only as it
23  *					is the fixed fuse point PN. It is not the system
24  *					configuration.
25  */
26 
27 static struct xe_tile *dev_to_tile(struct device *dev)
28 {
29 	return kobj_to_tile(dev->kobj.parent);
30 }
31 
32 static ssize_t max_freq_show(struct device *dev, struct device_attribute *attr,
33 			     char *buf)
34 {
35 	struct xe_tile *tile = dev_to_tile(dev);
36 	u32 val = 0, mbox;
37 	int err;
38 
39 	mbox = REG_FIELD_PREP(PCODE_MB_COMMAND, PCODE_FREQUENCY_CONFIG)
40 		| REG_FIELD_PREP(PCODE_MB_PARAM1, PCODE_MBOX_FC_SC_READ_FUSED_P0)
41 		| REG_FIELD_PREP(PCODE_MB_PARAM2, PCODE_MBOX_DOMAIN_HBM);
42 
43 	err = xe_pcode_read(tile, mbox, &val, NULL);
44 	if (err)
45 		return err;
46 
47 	/* data_out - Fused P0 for domain ID in units of 50 MHz */
48 	val *= 50;
49 
50 	return sysfs_emit(buf, "%u\n", val);
51 }
52 static DEVICE_ATTR_RO(max_freq);
53 
54 static ssize_t min_freq_show(struct device *dev, struct device_attribute *attr,
55 			     char *buf)
56 {
57 	struct xe_tile *tile = dev_to_tile(dev);
58 	u32 val = 0, mbox;
59 	int err;
60 
61 	mbox = REG_FIELD_PREP(PCODE_MB_COMMAND, PCODE_FREQUENCY_CONFIG)
62 		| REG_FIELD_PREP(PCODE_MB_PARAM1, PCODE_MBOX_FC_SC_READ_FUSED_PN)
63 		| REG_FIELD_PREP(PCODE_MB_PARAM2, PCODE_MBOX_DOMAIN_HBM);
64 
65 	err = xe_pcode_read(tile, mbox, &val, NULL);
66 	if (err)
67 		return err;
68 
69 	/* data_out - Fused Pn for domain ID in units of 50 MHz */
70 	val *= 50;
71 
72 	return sysfs_emit(buf, "%u\n", val);
73 }
74 static DEVICE_ATTR_RO(min_freq);
75 
76 static struct attribute *freq_attrs[] = {
77 	&dev_attr_max_freq.attr,
78 	&dev_attr_min_freq.attr,
79 	NULL
80 };
81 
82 static const struct attribute_group freq_group_attrs = {
83 	.name = "freq0",
84 	.attrs = freq_attrs,
85 };
86 
87 static void vram_freq_sysfs_fini(void *arg)
88 {
89 	struct kobject *kobj = arg;
90 
91 	sysfs_remove_group(kobj, &freq_group_attrs);
92 	kobject_put(kobj);
93 }
94 
95 /**
96  * xe_vram_freq_sysfs_init - Initialize vram frequency sysfs component
97  * @tile: Xe Tile object
98  *
99  * It needs to be initialized after the main tile component is ready
100  *
101  * Returns: 0 on success, negative error code on error.
102  */
103 int xe_vram_freq_sysfs_init(struct xe_tile *tile)
104 {
105 	struct xe_device *xe = tile_to_xe(tile);
106 	struct kobject *kobj;
107 	int err;
108 
109 	if (xe->info.platform != XE_PVC)
110 		return 0;
111 
112 	kobj = kobject_create_and_add("memory", tile->sysfs);
113 	if (!kobj)
114 		return -ENOMEM;
115 
116 	err = sysfs_create_group(kobj, &freq_group_attrs);
117 	if (err) {
118 		kobject_put(kobj);
119 		return err;
120 	}
121 
122 	return devm_add_action_or_reset(xe->drm.dev, vram_freq_sysfs_fini, kobj);
123 }
124