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
sof_ipc_flood_dfs_open(struct inode * inode,struct file * file)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 */
sof_debug_ipc_flood_test(struct sof_client_dev * cdev,bool flood_duration_test,unsigned long ipc_duration_ms,unsigned long ipc_count)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 */
sof_ipc_flood_dfs_write(struct file * file,const char __user * buffer,size_t count,loff_t * ppos)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 int err;
162 char *string;
163 int ret;
164
165 if (*ppos != 0)
166 return -EINVAL;
167
168 string = kzalloc(count + 1, GFP_KERNEL);
169 if (!string)
170 return -ENOMEM;
171
172 if (copy_from_user(string, buffer, count)) {
173 ret = -EFAULT;
174 goto out;
175 }
176
177 /*
178 * write op is only supported for ipc_flood_count or
179 * ipc_flood_duration_ms debugfs entries atm.
180 * ipc_flood_count floods the DSP with the number of IPC's specified.
181 * ipc_duration_ms test floods the DSP for the time specified
182 * in the debugfs entry.
183 */
184 if (debugfs_get_aux_num(file))
185 flood_duration_test = true;
186
187 /* test completion criterion */
188 if (flood_duration_test)
189 ret = kstrtoul(string, 0, &ipc_duration_ms);
190 else
191 ret = kstrtoul(string, 0, &ipc_count);
192 if (ret < 0)
193 goto out;
194
195 /* limit max duration/ipc count for flood test */
196 if (flood_duration_test) {
197 if (!ipc_duration_ms) {
198 ret = count;
199 goto out;
200 }
201
202 /* find the minimum. min() is not used to avoid warnings */
203 if (ipc_duration_ms > MAX_IPC_FLOOD_DURATION_MS)
204 ipc_duration_ms = MAX_IPC_FLOOD_DURATION_MS;
205 } else {
206 if (!ipc_count) {
207 ret = count;
208 goto out;
209 }
210
211 /* find the minimum. min() is not used to avoid warnings */
212 if (ipc_count > MAX_IPC_FLOOD_COUNT)
213 ipc_count = MAX_IPC_FLOOD_COUNT;
214 }
215
216 ret = pm_runtime_resume_and_get(dev);
217 if (ret < 0 && ret != -EACCES) {
218 dev_err_ratelimited(dev, "debugfs write failed to resume %d\n", ret);
219 goto out;
220 }
221
222 /* flood test */
223 ret = sof_debug_ipc_flood_test(cdev, flood_duration_test,
224 ipc_duration_ms, ipc_count);
225
226 pm_runtime_mark_last_busy(dev);
227 err = pm_runtime_put_autosuspend(dev);
228 if (err < 0)
229 dev_err_ratelimited(dev, "debugfs write failed to idle %d\n", err);
230
231 /* return count if test is successful */
232 if (ret >= 0)
233 ret = count;
234 out:
235 kfree(string);
236 return ret;
237 }
238
239 /* return the result of the last IPC flood test */
sof_ipc_flood_dfs_read(struct file * file,char __user * buffer,size_t count,loff_t * ppos)240 static ssize_t sof_ipc_flood_dfs_read(struct file *file, char __user *buffer,
241 size_t count, loff_t *ppos)
242 {
243 struct sof_client_dev *cdev = file->private_data;
244 struct sof_ipc_flood_priv *priv = cdev->data;
245 size_t size_ret;
246
247 if (*ppos)
248 return 0;
249
250 count = min_t(size_t, count, strlen(priv->buf));
251 size_ret = copy_to_user(buffer, priv->buf, count);
252 if (size_ret)
253 return -EFAULT;
254
255 *ppos += count;
256 return count;
257 }
258
sof_ipc_flood_dfs_release(struct inode * inode,struct file * file)259 static int sof_ipc_flood_dfs_release(struct inode *inode, struct file *file)
260 {
261 debugfs_file_put(file->f_path.dentry);
262
263 return 0;
264 }
265
266 static const struct file_operations sof_ipc_flood_fops = {
267 .open = sof_ipc_flood_dfs_open,
268 .read = sof_ipc_flood_dfs_read,
269 .llseek = default_llseek,
270 .write = sof_ipc_flood_dfs_write,
271 .release = sof_ipc_flood_dfs_release,
272
273 .owner = THIS_MODULE,
274 };
275
276 /*
277 * The IPC test client creates a couple of debugfs entries that will be used
278 * flood tests. Users can write to these entries to execute the IPC flood test
279 * by specifying either the number of IPCs to flood the DSP with or the duration
280 * (in ms) for which the DSP should be flooded with test IPCs. At the
281 * end of each test, the average, min and max response times are reported back.
282 * The results of the last flood test can be accessed by reading the debugfs
283 * entries.
284 */
sof_ipc_flood_probe(struct auxiliary_device * auxdev,const struct auxiliary_device_id * id)285 static int sof_ipc_flood_probe(struct auxiliary_device *auxdev,
286 const struct auxiliary_device_id *id)
287 {
288 struct sof_client_dev *cdev = auxiliary_dev_to_sof_client_dev(auxdev);
289 struct dentry *debugfs_root = sof_client_get_debugfs_root(cdev);
290 struct device *dev = &auxdev->dev;
291 struct sof_ipc_flood_priv *priv;
292
293 /* allocate memory for client data */
294 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
295 if (!priv)
296 return -ENOMEM;
297
298 priv->buf = devm_kmalloc(dev, IPC_FLOOD_TEST_RESULT_LEN, GFP_KERNEL);
299 if (!priv->buf)
300 return -ENOMEM;
301
302 cdev->data = priv;
303
304 /* create debugfs root folder with device name under parent SOF dir */
305 priv->dfs_root = debugfs_create_dir(dev_name(dev), debugfs_root);
306 if (!IS_ERR_OR_NULL(priv->dfs_root)) {
307 /* create read-write ipc_flood_count debugfs entry */
308 debugfs_create_file_aux_num(DEBUGFS_IPC_FLOOD_COUNT, 0644,
309 priv->dfs_root, cdev, 0, &sof_ipc_flood_fops);
310
311 /* create read-write ipc_flood_duration_ms debugfs entry */
312 debugfs_create_file_aux_num(DEBUGFS_IPC_FLOOD_DURATION, 0644,
313 priv->dfs_root, cdev, 1, &sof_ipc_flood_fops);
314
315 if (auxdev->id == 0) {
316 /*
317 * Create symlinks for backwards compatibility to the
318 * first IPC flood test instance
319 */
320 char target[100];
321
322 snprintf(target, 100, "%s/" DEBUGFS_IPC_FLOOD_COUNT,
323 dev_name(dev));
324 priv->dfs_link[0] =
325 debugfs_create_symlink(DEBUGFS_IPC_FLOOD_COUNT,
326 debugfs_root, target);
327
328 snprintf(target, 100, "%s/" DEBUGFS_IPC_FLOOD_DURATION,
329 dev_name(dev));
330 priv->dfs_link[1] =
331 debugfs_create_symlink(DEBUGFS_IPC_FLOOD_DURATION,
332 debugfs_root, target);
333 }
334 }
335
336 /* enable runtime PM */
337 pm_runtime_set_autosuspend_delay(dev, SOF_IPC_CLIENT_SUSPEND_DELAY_MS);
338 pm_runtime_use_autosuspend(dev);
339 pm_runtime_enable(dev);
340 pm_runtime_mark_last_busy(dev);
341 pm_runtime_idle(dev);
342
343 return 0;
344 }
345
sof_ipc_flood_remove(struct auxiliary_device * auxdev)346 static void sof_ipc_flood_remove(struct auxiliary_device *auxdev)
347 {
348 struct sof_client_dev *cdev = auxiliary_dev_to_sof_client_dev(auxdev);
349 struct sof_ipc_flood_priv *priv = cdev->data;
350
351 pm_runtime_disable(&auxdev->dev);
352
353 if (auxdev->id == 0) {
354 debugfs_remove(priv->dfs_link[0]);
355 debugfs_remove(priv->dfs_link[1]);
356 }
357
358 debugfs_remove_recursive(priv->dfs_root);
359 }
360
361 static const struct auxiliary_device_id sof_ipc_flood_client_id_table[] = {
362 { .name = "snd_sof.ipc_flood" },
363 {},
364 };
365 MODULE_DEVICE_TABLE(auxiliary, sof_ipc_flood_client_id_table);
366
367 /*
368 * No need for driver pm_ops as the generic pm callbacks in the auxiliary bus
369 * type are enough to ensure that the parent SOF device resumes to bring the DSP
370 * back to D0.
371 * Driver name will be set based on KBUILD_MODNAME.
372 */
373 static struct auxiliary_driver sof_ipc_flood_client_drv = {
374 .probe = sof_ipc_flood_probe,
375 .remove = sof_ipc_flood_remove,
376
377 .id_table = sof_ipc_flood_client_id_table,
378 };
379
380 module_auxiliary_driver(sof_ipc_flood_client_drv);
381
382 MODULE_LICENSE("GPL");
383 MODULE_DESCRIPTION("SOF IPC Flood Test Client Driver");
384 MODULE_IMPORT_NS("SND_SOC_SOF_CLIENT");
385