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