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
233static __always_inline void
234_i915_param_create_file(struct dentry *parent, const char *name,
235			const char *type, int mode, void *value)
236{
237	if (!mode)
238		return;
239
240	if (!__builtin_strcmp(type, "bool"))
241		debugfs_create_bool(name, mode, parent, value);
242	else if (!__builtin_strcmp(type, "int"))
243		i915_debugfs_create_int(name, mode, parent, value);
244	else if (!__builtin_strcmp(type, "unsigned int"))
245		i915_debugfs_create_uint(name, mode, parent, value);
246	else if (!__builtin_strcmp(type, "unsigned long"))
247		debugfs_create_ulong(name, mode, parent, value);
248	else if (!__builtin_strcmp(type, "char *"))
249		i915_debugfs_create_charp(name, mode, parent, value);
250	else
251		WARN(1, "no debugfs fops defined for param type %s (i915.%s)\n",
252		     type, name);
253}
254
255/* add a subdirectory with files for each i915 param */
256struct dentry *i915_debugfs_params(struct drm_i915_private *i915)
257{
258	struct drm_minor *minor = i915->drm.primary;
259	struct i915_params *params = &i915->params;
260	struct dentry *dir;
261
262	dir = debugfs_create_dir("i915_params", minor->debugfs_root);
263	if (IS_ERR(dir))
264		return dir;
265
266	/*
267	 * Note: We could create files for params needing special handling
268	 * here. Set mode in params to 0 to skip the generic create file, or
269	 * just let the generic create file fail silently with -EEXIST.
270	 */
271
272#define REGISTER(T, x, unused, mode, ...) _i915_param_create_file(dir, #x, #T, mode, &params->x);
273	I915_PARAMS_FOR_EACH(REGISTER);
274#undef REGISTER
275
276	return dir;
277}