1 // SPDX-License-Identifier: GPL-2.0-only
2 //
3 // Copyright(c) 2022 Intel Corporation
4 //
5 // Authors: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
6 // Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
7 //
8
9 #include <linux/auxiliary_bus.h>
10 #include <linux/completion.h>
11 #include <linux/debugfs.h>
12 #include <linux/ktime.h>
13 #include <linux/mod_devicetable.h>
14 #include <linux/module.h>
15 #include <linux/pm_runtime.h>
16 #include <linux/slab.h>
17 #include <linux/uaccess.h>
18 #include <sound/sof/header.h>
19
20 #include "sof-client.h"
21
22 #define MAX_IPC_FLOOD_DURATION_MS 1000
23 #define MAX_IPC_FLOOD_COUNT 10000
24 #define IPC_FLOOD_TEST_RESULT_LEN 512
25 #define SOF_IPC_CLIENT_SUSPEND_DELAY_MS 3000
26
27 #define DEBUGFS_IPC_FLOOD_COUNT "ipc_flood_count"
28 #define DEBUGFS_IPC_FLOOD_DURATION "ipc_flood_duration_ms"
29
30 struct sof_ipc_flood_priv {
31 struct dentry *dfs_root;
32 struct dentry *dfs_link[2];
33 char *buf;
34 };
35
36 static int sof_ipc_flood_dfs_open(struct inode *inode, struct file *file)
37 {
38 struct sof_client_dev *cdev = inode->i_private;
39 int ret;
40
41 if (sof_client_get_fw_state(cdev) == SOF_FW_CRASHED)
42 return -ENODEV;
43
44 ret = debugfs_file_get(file->f_path.dentry);
45 if (unlikely(ret))
46 return ret;
47
48 ret = simple_open(inode, file);
49 if (ret)
50 debugfs_file_put(file->f_path.dentry);
51
52 return ret;
53 }
54
55 /*
56 * helper function to perform the flood test. Only one of the two params, ipc_duration_ms
57 * or ipc_count, will be non-zero and will determine the type of test
58 */
59 static int sof_debug_ipc_flood_test(struct sof_client_dev *cdev,
60 bool flood_duration_test,
61 unsigned long ipc_duration_ms,
62 unsigned long ipc_count)
63 {
64 struct sof_ipc_flood_priv *priv = cdev->data;
65 struct device *dev = &cdev->auxdev.dev;
66 struct sof_ipc_cmd_hdr hdr;
67 u64 min_response_time = U64_MAX;
68 ktime_t start, end, test_end;
69 u64 avg_response_time = 0;
70 u64 max_response_time = 0;
71 u64 ipc_response_time;
72 int i = 0;
73 int ret;
74
75 /* configure test IPC */
76 hdr.cmd = SOF_IPC_GLB_TEST_MSG | SOF_IPC_TEST_IPC_FLOOD;
77 hdr.size = sizeof(hdr);
78
79 /* set test end time for duration flood test */
80 if (flood_duration_test)
81 test_end = ktime_get_ns() + ipc_duration_ms * NSEC_PER_MSEC;
82
83 /* send test IPC's */
84 while (1) {
85 start = ktime_get();
86 ret = sof_client_ipc_tx_message_no_reply(cdev, &hdr);
87 end = ktime_get();
88
89 if (ret < 0)
90 break;
91
92 /* compute min and max response times */
93 ipc_response_time = ktime_to_ns(ktime_sub(end, start));
94 min_response_time = min(min_response_time, ipc_response_time);
95 max_response_time = max(max_response_time, ipc_response_time);
96
97 /* sum up response times */
98 avg_response_time += ipc_response_time;
99 i++;
100
101 /* test complete? */
102 if (flood_duration_test) {
103 if (ktime_to_ns(end) >= test_end)
104 break;
105 } else {
106 if (i == ipc_count)
107 break;
108 }
109 }
110
111 if (ret < 0)
112 dev_err(dev, "ipc flood test failed at %d iterations\n", i);
113
114 /* return if the first IPC fails */
115 if (!i)
116 return ret;
117
118 /* compute average response time */
119 do_div(avg_response_time, i);
120
121 /* clear previous test output */
122 memset(priv->buf, 0, IPC_FLOOD_TEST_RESULT_LEN);
123
124 if (!ipc_count) {
125 dev_dbg(dev, "IPC Flood test duration: %lums\n", ipc_duration_ms);
126 snprintf(priv->buf, IPC_FLOOD_TEST_RESULT_LEN,
127 "IPC Flood test duration: %lums\n", ipc_duration_ms);
128 }
129
130 dev_dbg(dev, "IPC Flood count: %d, Avg response time: %lluns\n",
131 i, avg_response_time);
132 dev_dbg(dev, "Max response time: %lluns\n", max_response_time);
133 dev_dbg(dev, "Min response time: %lluns\n", min_response_time);
134
135 /* format output string and save test results */
136 snprintf(priv->buf + strlen(priv->buf),
137 IPC_FLOOD_TEST_RESULT_LEN - strlen(priv->buf),
138 "IPC Flood count: %d\nAvg response time: %lluns\n",
139 i, avg_response_time);
140
141 snprintf(priv->buf + strlen(priv->buf),
142 IPC_FLOOD_TEST_RESULT_LEN - strlen(priv->buf),
143 "Max response time: %lluns\nMin response time: %lluns\n",
144 max_response_time, min_response_time);
145
146 return ret;
147 }
148
149 /*
150 * Writing to the debugfs entry initiates the IPC flood test based on
151 * the IPC count or the duration specified by the user.
152 */
153 static ssize_t sof_ipc_flood_dfs_write(struct file *file, const char __user *buffer,
154 size_t count, loff_t *ppos)
155 {
156 struct sof_client_dev *cdev = file->private_data;
157 struct device *dev = &cdev->auxdev.dev;
158 unsigned long ipc_duration_ms = 0;
159 bool flood_duration_test = false;
160 unsigned long ipc_count = 0;
161 struct dentry *dentry;
162 int err;
163 char *string;
164 int ret;
165
166 if (*ppos != 0)
167 return -EINVAL;
168
169 string = kzalloc(count + 1, GFP_KERNEL);
170 if (!string)
171 return -ENOMEM;
172
173 if (copy_from_user(string, buffer, count)) {
174 ret = -EFAULT;
175 goto out;
176 }
177
178 /*
179 * write op is only supported for ipc_flood_count or
180 * ipc_flood_duration_ms debugfs entries atm.
181 * ipc_flood_count floods the DSP with the number of IPC's specified.
182 * ipc_duration_ms test floods the DSP for the time specified
183 * in the debugfs entry.
184 */
185 dentry = file->f_path.dentry;
186 if (strcmp(dentry->d_name.name, DEBUGFS_IPC_FLOOD_COUNT) &&
187 strcmp(dentry->d_name.name, DEBUGFS_IPC_FLOOD_DURATION)) {
188 ret = -EINVAL;
189 goto out;
190 }
191
192 if (!strcmp(dentry->d_name.name, DEBUGFS_IPC_FLOOD_DURATION))
193 flood_duration_test = true;
194
195 /* test completion criterion */
196 if (flood_duration_test)
197 ret = kstrtoul(string, 0, &ipc_duration_ms);
198 else
199 ret = kstrtoul(string, 0, &ipc_count);
200 if (ret < 0)
201 goto out;
202
203 /* limit max duration/ipc count for flood test */
204 if (flood_duration_test) {
205 if (!ipc_duration_ms) {
206 ret = count;
207 goto out;
208 }
209
210 /* find the minimum. min() is not used to avoid warnings */
211 if (ipc_duration_ms > MAX_IPC_FLOOD_DURATION_MS)
212 ipc_duration_ms = MAX_IPC_FLOOD_DURATION_MS;
213 } else {
214 if (!ipc_count) {
215 ret = count;
216 goto out;
217 }
218
219 /* find the minimum. min() is not used to avoid warnings */
220 if (ipc_count > MAX_IPC_FLOOD_COUNT)
221 ipc_count = MAX_IPC_FLOOD_COUNT;
222 }
223
224 ret = pm_runtime_resume_and_get(dev);
225 if (ret < 0 && ret != -EACCES) {
226 dev_err_ratelimited(dev, "debugfs write failed to resume %d\n", ret);
227 goto out;
228 }
229
230 /* flood test */
231 ret = sof_debug_ipc_flood_test(cdev, flood_duration_test,
232 ipc_duration_ms, ipc_count);
233
234 pm_runtime_mark_last_busy(dev);
235 err = pm_runtime_put_autosuspend(dev);
236 if (err < 0)
237 dev_err_ratelimited(dev, "debugfs write failed to idle %d\n", err);
238
239 /* return count if test is successful */
240 if (ret >= 0)
241 ret = count;
242 out:
243 kfree(string);
244 return ret;
245 }
246
247 /* return the result of the last IPC flood test */
248 static ssize_t sof_ipc_flood_dfs_read(struct file *file, char __user *buffer,
249 size_t count, loff_t *ppos)
250 {
251 struct sof_client_dev *cdev = file->private_data;
252 struct sof_ipc_flood_priv *priv = cdev->data;
253 size_t size_ret;
254
255 struct dentry *dentry;
256
257 dentry = file->f_path.dentry;
258 if (!strcmp(dentry->d_name.name, DEBUGFS_IPC_FLOOD_COUNT) ||
259 !strcmp(dentry->d_name.name, DEBUGFS_IPC_FLOOD_DURATION)) {
260 if (*ppos)
261 return 0;
262
263 count = min_t(size_t, count, strlen(priv->buf));
264 size_ret = copy_to_user(buffer, priv->buf, count);
265 if (size_ret)
266 return -EFAULT;
267
268 *ppos += count;
269 return count;
270 }
271 return count;
272 }
273
274 static int sof_ipc_flood_dfs_release(struct inode *inode, struct file *file)
275 {
276 debugfs_file_put(file->f_path.dentry);
277
278 return 0;
279 }
280
281 static const struct file_operations sof_ipc_flood_fops = {
282 .open = sof_ipc_flood_dfs_open,
283 .read = sof_ipc_flood_dfs_read,
284 .llseek = default_llseek,
285 .write = sof_ipc_flood_dfs_write,
286 .release = sof_ipc_flood_dfs_release,
287
288 .owner = THIS_MODULE,
289 };
290
291 /*
292 * The IPC test client creates a couple of debugfs entries that will be used
293 * flood tests. Users can write to these entries to execute the IPC flood test
294 * by specifying either the number of IPCs to flood the DSP with or the duration
295 * (in ms) for which the DSP should be flooded with test IPCs. At the
296 * end of each test, the average, min and max response times are reported back.
297 * The results of the last flood test can be accessed by reading the debugfs
298 * entries.
299 */
300 static int sof_ipc_flood_probe(struct auxiliary_device *auxdev,
301 const struct auxiliary_device_id *id)
302 {
303 struct sof_client_dev *cdev = auxiliary_dev_to_sof_client_dev(auxdev);
304 struct dentry *debugfs_root = sof_client_get_debugfs_root(cdev);
305 struct device *dev = &auxdev->dev;
306 struct sof_ipc_flood_priv *priv;
307
308 /* allocate memory for client data */
309 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
310 if (!priv)
311 return -ENOMEM;
312
313 priv->buf = devm_kmalloc(dev, IPC_FLOOD_TEST_RESULT_LEN, GFP_KERNEL);
314 if (!priv->buf)
315 return -ENOMEM;
316
317 cdev->data = priv;
318
319 /* create debugfs root folder with device name under parent SOF dir */
320 priv->dfs_root = debugfs_create_dir(dev_name(dev), debugfs_root);
321 if (!IS_ERR_OR_NULL(priv->dfs_root)) {
322 /* create read-write ipc_flood_count debugfs entry */
323 debugfs_create_file(DEBUGFS_IPC_FLOOD_COUNT, 0644, priv->dfs_root,
324 cdev, &sof_ipc_flood_fops);
325
326 /* create read-write ipc_flood_duration_ms debugfs entry */
327 debugfs_create_file(DEBUGFS_IPC_FLOOD_DURATION, 0644,
328 priv->dfs_root, cdev, &sof_ipc_flood_fops);
329
330 if (auxdev->id == 0) {
331 /*
332 * Create symlinks for backwards compatibility to the
333 * first IPC flood test instance
334 */
335 char target[100];
336
337 snprintf(target, 100, "%s/" DEBUGFS_IPC_FLOOD_COUNT,
338 dev_name(dev));
339 priv->dfs_link[0] =
340 debugfs_create_symlink(DEBUGFS_IPC_FLOOD_COUNT,
341 debugfs_root, target);
342
343 snprintf(target, 100, "%s/" DEBUGFS_IPC_FLOOD_DURATION,
344 dev_name(dev));
345 priv->dfs_link[1] =
346 debugfs_create_symlink(DEBUGFS_IPC_FLOOD_DURATION,
347 debugfs_root, target);
348 }
349 }
350
351 /* enable runtime PM */
352 pm_runtime_set_autosuspend_delay(dev, SOF_IPC_CLIENT_SUSPEND_DELAY_MS);
353 pm_runtime_use_autosuspend(dev);
354 pm_runtime_enable(dev);
355 pm_runtime_mark_last_busy(dev);
356 pm_runtime_idle(dev);
357
358 return 0;
359 }
360
361 static void sof_ipc_flood_remove(struct auxiliary_device *auxdev)
362 {
363 struct sof_client_dev *cdev = auxiliary_dev_to_sof_client_dev(auxdev);
364 struct sof_ipc_flood_priv *priv = cdev->data;
365
366 pm_runtime_disable(&auxdev->dev);
367
368 if (auxdev->id == 0) {
369 debugfs_remove(priv->dfs_link[0]);
370 debugfs_remove(priv->dfs_link[1]);
371 }
372
373 debugfs_remove_recursive(priv->dfs_root);
374 }
375
376 static const struct auxiliary_device_id sof_ipc_flood_client_id_table[] = {
377 { .name = "snd_sof.ipc_flood" },
378 {},
379 };
380 MODULE_DEVICE_TABLE(auxiliary, sof_ipc_flood_client_id_table);
381
382 /*
383 * No need for driver pm_ops as the generic pm callbacks in the auxiliary bus
384 * type are enough to ensure that the parent SOF device resumes to bring the DSP
385 * back to D0.
386 * Driver name will be set based on KBUILD_MODNAME.
387 */
388 static struct auxiliary_driver sof_ipc_flood_client_drv = {
389 .probe = sof_ipc_flood_probe,
390 .remove = sof_ipc_flood_remove,
391
392 .id_table = sof_ipc_flood_client_id_table,
393 };
394
395 module_auxiliary_driver(sof_ipc_flood_client_drv);
396
397 MODULE_LICENSE("GPL");
398 MODULE_DESCRIPTION("SOF IPC Flood Test Client Driver");
399 MODULE_IMPORT_NS(SND_SOC_SOF_CLIENT);
400
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