1// SPDX-License-Identifier: MIT
2/*
3 * Copyright © 2019 Intel Corporation
4 */
5
6#include <linux/kernel.h>
7#include <linux/debugfs.h>
8
9#include "i915_debugfs_params.h"
10#include "gt/intel_gt.h"
11#include "gt/uc/intel_guc.h"
12#include "i915_drv.h"
13#include "i915_params.h"
14
15#define MATCH_DEBUGFS_NODE_NAME(_file, _name) \
16 (strcmp((_file)->f_path.dentry->d_name.name, (_name)) == 0)
17
18#define GET_I915(i915, name, ptr) \
19 do { \
20 struct i915_params *params; \
21 params = container_of(((void *)(ptr)), typeof(*params), name); \
22 (i915) = container_of(params, typeof(*(i915)), params); \
23 } while (0)
24
25/* int param */
26static int i915_param_int_show(struct seq_file *m, void *data)
27{
28 int *value = m->private;
29
30 seq_printf(m, fmt: "%d\n", *value);
31
32 return 0;
33}
34
35static int i915_param_int_open(struct inode *inode, struct file *file)
36{
37 return single_open(file, i915_param_int_show, inode->i_private);
38}
39
40static int notify_guc(struct drm_i915_private *i915)
41{
42 struct intel_gt *gt;
43 int i, ret = 0;
44
45 for_each_gt(gt, i915, i) {
46 if (intel_uc_uses_guc_submission(uc: &gt->uc))
47 ret = intel_guc_global_policies_update(guc: &gt->uc.guc);
48 }
49
50 return ret;
51}
52
53static ssize_t i915_param_int_write(struct file *file,
54 const char __user *ubuf, size_t len,
55 loff_t *offp)
56{
57 struct seq_file *m = file->private_data;
58 int *value = m->private;
59 int ret;
60
61 ret = kstrtoint_from_user(s: ubuf, count: len, base: 0, res: value);
62 if (ret) {
63 /* support boolean values too */
64 bool b;
65
66 ret = kstrtobool_from_user(s: ubuf, count: len, res: &b);
67 if (!ret)
68 *value = b;
69 }
70
71 return ret ?: len;
72}
73
74static const struct file_operations i915_param_int_fops = {
75 .owner = THIS_MODULE,
76 .open = i915_param_int_open,
77 .read = seq_read,
78 .write = i915_param_int_write,
79 .llseek = default_llseek,
80 .release = single_release,
81};
82
83static const struct file_operations i915_param_int_fops_ro = {
84 .owner = THIS_MODULE,
85 .open = i915_param_int_open,
86 .read = seq_read,
87 .llseek = default_llseek,
88 .release = single_release,
89};
90
91/* unsigned int param */
92static int i915_param_uint_show(struct seq_file *m, void *data)
93{
94 unsigned int *value = m->private;
95
96 seq_printf(m, fmt: "%u\n", *value);
97
98 return 0;
99}
100
101static int i915_param_uint_open(struct inode *inode, struct file *file)
102{
103 return single_open(file, i915_param_uint_show, inode->i_private);
104}
105
106static ssize_t i915_param_uint_write(struct file *file,
107 const char __user *ubuf, size_t len,
108 loff_t *offp)
109{
110 struct drm_i915_private *i915;
111 struct seq_file *m = file->private_data;
112 unsigned int *value = m->private;
113 unsigned int old = *value;
114 int ret;
115
116 ret = kstrtouint_from_user(s: ubuf, count: len, base: 0, res: value);
117 if (ret) {
118 /* support boolean values too */
119 bool b;
120
121 ret = kstrtobool_from_user(s: ubuf, count: len, res: &b);
122 if (!ret)
123 *value = b;
124 }
125
126 if (!ret && MATCH_DEBUGFS_NODE_NAME(file, "reset")) {
127 GET_I915(i915, reset, value);
128
129 ret = notify_guc(i915);
130 if (ret)
131 *value = old;
132 }
133
134 return ret ?: len;
135}
136
137static const struct file_operations i915_param_uint_fops = {
138 .owner = THIS_MODULE,
139 .open = i915_param_uint_open,
140 .read = seq_read,
141 .write = i915_param_uint_write,
142 .llseek = default_llseek,
143 .release = single_release,
144};
145
146static const struct file_operations i915_param_uint_fops_ro = {
147 .owner = THIS_MODULE,
148 .open = i915_param_uint_open,
149 .read = seq_read,
150 .llseek = default_llseek,
151 .release = single_release,
152};
153
154/* char * param */
155static int i915_param_charp_show(struct seq_file *m, void *data)
156{
157 const char **s = m->private;
158
159 seq_printf(m, fmt: "%s\n", *s);
160
161 return 0;
162}
163
164static int i915_param_charp_open(struct inode *inode, struct file *file)
165{
166 return single_open(file, i915_param_charp_show, inode->i_private);
167}
168
169static ssize_t i915_param_charp_write(struct file *file,
170 const char __user *ubuf, size_t len,
171 loff_t *offp)
172{
173 struct seq_file *m = file->private_data;
174 char **s = m->private;
175 char *new, *old;
176
177 old = *s;
178 new = strndup_user(ubuf, PAGE_SIZE);
179 if (IS_ERR(ptr: new)) {
180 len = PTR_ERR(ptr: new);
181 goto out;
182 }
183
184 *s = new;
185
186 kfree(objp: old);
187out:
188 return len;
189}
190
191static const struct file_operations i915_param_charp_fops = {
192 .owner = THIS_MODULE,
193 .open = i915_param_charp_open,
194 .read = seq_read,
195 .write = i915_param_charp_write,
196 .llseek = default_llseek,
197 .release = single_release,
198};
199
200static const struct file_operations i915_param_charp_fops_ro = {
201 .owner = THIS_MODULE,
202 .open = i915_param_charp_open,
203 .read = seq_read,
204 .llseek = default_llseek,
205 .release = single_release,
206};
207
208#define RO(mode) (((mode) & 0222) == 0)
209
210static struct dentry *
211i915_debugfs_create_int(const char *name, umode_t mode,
212 struct dentry *parent, int *value)
213{
214 return debugfs_create_file_unsafe(name, mode, parent, data: value,
215 RO(mode) ? &i915_param_int_fops_ro :
216 &i915_param_int_fops);
217}
218
219static struct dentry *
220i915_debugfs_create_uint(const char *name, umode_t mode,
221 struct dentry *parent, unsigned int *value)
222{
223 return debugfs_create_file_unsafe(name, mode, parent, data: value,
224 RO(mode) ? &i915_param_uint_fops_ro :
225 &i915_param_uint_fops);
226}
227
228static struct dentry *
229i915_debugfs_create_charp(const char *name, umode_t mode,
230 struct dentry *parent, char **value)
231{
232 return debugfs_create_file(name, mode, parent, value,
233 RO(mode) ? &i915_param_charp_fops_ro :
234 &i915_param_charp_fops);
235}
236
237#define _i915_param_create_file(parent, name, mode, valp) \
238 do { \
239 if (mode) \
240 _Generic(valp, \
241 bool *: debugfs_create_bool, \
242 int *: i915_debugfs_create_int, \
243 unsigned int *: i915_debugfs_create_uint, \
244 unsigned long *: debugfs_create_ulong, \
245 char **: i915_debugfs_create_charp)(name, mode, parent, valp); \
246 } while(0)
247
248/* add a subdirectory with files for each i915 param */
249struct dentry *i915_debugfs_params(struct drm_i915_private *i915)
250{
251 struct dentry *debugfs_root = i915->drm.debugfs_root;
252 struct i915_params *params = &i915->params;
253 struct dentry *dir;
254
255 dir = debugfs_create_dir(name: "i915_params", parent: debugfs_root);
256 if (IS_ERR(ptr: dir))
257 return dir;
258
259 /*
260 * Note: We could create files for params needing special handling
261 * here. Set mode in params to 0 to skip the generic create file, or
262 * just let the generic create file fail silently with -EEXIST.
263 */
264
265#define REGISTER(T, x, unused, mode, ...) _i915_param_create_file(dir, #x, mode, &params->x);
266 I915_PARAMS_FOR_EACH(REGISTER);
267#undef REGISTER
268
269 return dir;
270}
271

source code of linux/drivers/gpu/drm/i915/i915_debugfs_params.c