xref: /linux/drivers/gpu/drm/i915/i915_debugfs_params.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
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 */
26 static int i915_param_int_show(struct seq_file *m, void *data)
27 {
28 	int *value = m->private;
29 
30 	seq_printf(m, "%d\n", *value);
31 
32 	return 0;
33 }
34 
35 static 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 
40 static 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(&gt->uc))
47 			ret = intel_guc_global_policies_update(&gt->uc.guc);
48 	}
49 
50 	return ret;
51 }
52 
53 static 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(ubuf, len, 0, value);
62 	if (ret) {
63 		/* support boolean values too */
64 		bool b;
65 
66 		ret = kstrtobool_from_user(ubuf, len, &b);
67 		if (!ret)
68 			*value = b;
69 	}
70 
71 	return ret ?: len;
72 }
73 
74 static 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 
83 static 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 */
92 static int i915_param_uint_show(struct seq_file *m, void *data)
93 {
94 	unsigned int *value = m->private;
95 
96 	seq_printf(m, "%u\n", *value);
97 
98 	return 0;
99 }
100 
101 static 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 
106 static 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(ubuf, len, 0, value);
117 	if (ret) {
118 		/* support boolean values too */
119 		bool b;
120 
121 		ret = kstrtobool_from_user(ubuf, len, &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 
137 static 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 
146 static 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 */
155 static int i915_param_charp_show(struct seq_file *m, void *data)
156 {
157 	const char **s = m->private;
158 
159 	seq_printf(m, "%s\n", *s);
160 
161 	return 0;
162 }
163 
164 static 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 
169 static 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(new)) {
180 		len = PTR_ERR(new);
181 		goto out;
182 	}
183 
184 	*s = new;
185 
186 	kfree(old);
187 out:
188 	return len;
189 }
190 
191 static 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 
200 static 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 
210 static struct dentry *
211 i915_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, value,
215 					  RO(mode) ? &i915_param_int_fops_ro :
216 					  &i915_param_int_fops);
217 }
218 
219 static struct dentry *
220 i915_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, value,
224 					  RO(mode) ? &i915_param_uint_fops_ro :
225 					  &i915_param_uint_fops);
226 }
227 
228 static struct dentry *
229 i915_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 */
249 struct dentry *i915_debugfs_params(struct drm_i915_private *i915)
250 {
251 	struct drm_minor *minor = i915->drm.primary;
252 	struct i915_params *params = &i915->params;
253 	struct dentry *dir;
254 
255 	dir = debugfs_create_dir("i915_params", minor->debugfs_root);
256 	if (IS_ERR(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