xref: /openbmc/linux/sound/soc/sof/debug.c (revision 2022ca0a)
1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
2 //
3 // This file is provided under a dual BSD/GPLv2 license.  When using or
4 // redistributing this file, you may do so under either license.
5 //
6 // Copyright(c) 2018 Intel Corporation. All rights reserved.
7 //
8 // Author: Liam Girdwood <liam.r.girdwood@linux.intel.com>
9 //
10 // Generic debug routines used to export DSP MMIO and memories to userspace
11 // for firmware debugging.
12 //
13 
14 #include <linux/debugfs.h>
15 #include <linux/io.h>
16 #include <linux/pm_runtime.h>
17 #include "sof-priv.h"
18 #include "ops.h"
19 
20 #if IS_ENABLED(CONFIG_SND_SOC_SOF_DEBUG_IPC_FLOOD_TEST)
21 #define MAX_IPC_FLOOD_DURATION_MS 1000
22 #define MAX_IPC_FLOOD_COUNT 10000
23 #define IPC_FLOOD_TEST_RESULT_LEN 512
24 
25 static int sof_debug_ipc_flood_test(struct snd_sof_dev *sdev,
26 				    struct snd_sof_dfsentry *dfse,
27 				    bool flood_duration_test,
28 				    unsigned long ipc_duration_ms,
29 				    unsigned long ipc_count)
30 {
31 	struct sof_ipc_cmd_hdr hdr;
32 	struct sof_ipc_reply reply;
33 	u64 min_response_time = U64_MAX;
34 	ktime_t start, end, test_end;
35 	u64 avg_response_time = 0;
36 	u64 max_response_time = 0;
37 	u64 ipc_response_time;
38 	int i = 0;
39 	int ret;
40 
41 	/* configure test IPC */
42 	hdr.cmd = SOF_IPC_GLB_TEST_MSG | SOF_IPC_TEST_IPC_FLOOD;
43 	hdr.size = sizeof(hdr);
44 
45 	/* set test end time for duration flood test */
46 	if (flood_duration_test)
47 		test_end = ktime_get_ns() + ipc_duration_ms * NSEC_PER_MSEC;
48 
49 	/* send test IPC's */
50 	while (1) {
51 		start = ktime_get();
52 		ret = sof_ipc_tx_message(sdev->ipc, hdr.cmd, &hdr, hdr.size,
53 					 &reply, sizeof(reply));
54 		end = ktime_get();
55 
56 		if (ret < 0)
57 			break;
58 
59 		/* compute min and max response times */
60 		ipc_response_time = ktime_to_ns(ktime_sub(end, start));
61 		min_response_time = min(min_response_time, ipc_response_time);
62 		max_response_time = max(max_response_time, ipc_response_time);
63 
64 		/* sum up response times */
65 		avg_response_time += ipc_response_time;
66 		i++;
67 
68 		/* test complete? */
69 		if (flood_duration_test) {
70 			if (ktime_to_ns(end) >= test_end)
71 				break;
72 		} else {
73 			if (i == ipc_count)
74 				break;
75 		}
76 	}
77 
78 	if (ret < 0)
79 		dev_err(sdev->dev,
80 			"error: ipc flood test failed at %d iterations\n", i);
81 
82 	/* return if the first IPC fails */
83 	if (!i)
84 		return ret;
85 
86 	/* compute average response time */
87 	do_div(avg_response_time, i);
88 
89 	/* clear previous test output */
90 	memset(dfse->cache_buf, 0, IPC_FLOOD_TEST_RESULT_LEN);
91 
92 	if (flood_duration_test) {
93 		dev_dbg(sdev->dev, "IPC Flood test duration: %lums\n",
94 			ipc_duration_ms);
95 		snprintf(dfse->cache_buf, IPC_FLOOD_TEST_RESULT_LEN,
96 			 "IPC Flood test duration: %lums\n", ipc_duration_ms);
97 	}
98 
99 	dev_dbg(sdev->dev,
100 		"IPC Flood count: %d, Avg response time: %lluns\n",
101 		i, avg_response_time);
102 	dev_dbg(sdev->dev, "Max response time: %lluns\n",
103 		max_response_time);
104 	dev_dbg(sdev->dev, "Min response time: %lluns\n",
105 		min_response_time);
106 
107 	/* format output string */
108 	snprintf(dfse->cache_buf + strlen(dfse->cache_buf),
109 		 IPC_FLOOD_TEST_RESULT_LEN - strlen(dfse->cache_buf),
110 		 "IPC Flood count: %d\nAvg response time: %lluns\n",
111 		 i, avg_response_time);
112 
113 	snprintf(dfse->cache_buf + strlen(dfse->cache_buf),
114 		 IPC_FLOOD_TEST_RESULT_LEN - strlen(dfse->cache_buf),
115 		 "Max response time: %lluns\nMin response time: %lluns\n",
116 		 max_response_time, min_response_time);
117 
118 	return ret;
119 }
120 #endif
121 
122 static ssize_t sof_dfsentry_write(struct file *file, const char __user *buffer,
123 				  size_t count, loff_t *ppos)
124 {
125 #if IS_ENABLED(CONFIG_SND_SOC_SOF_DEBUG_IPC_FLOOD_TEST)
126 	struct snd_sof_dfsentry *dfse = file->private_data;
127 	struct snd_sof_dev *sdev = dfse->sdev;
128 	unsigned long ipc_duration_ms = 0;
129 	bool flood_duration_test = false;
130 	unsigned long ipc_count = 0;
131 	struct dentry *dentry;
132 	int err;
133 #endif
134 	size_t size;
135 	char *string;
136 	int ret;
137 
138 	string = kzalloc(count, GFP_KERNEL);
139 	if (!string)
140 		return -ENOMEM;
141 
142 	size = simple_write_to_buffer(string, count, ppos, buffer, count);
143 	ret = size;
144 
145 #if IS_ENABLED(CONFIG_SND_SOC_SOF_DEBUG_IPC_FLOOD_TEST)
146 	/*
147 	 * write op is only supported for ipc_flood_count or
148 	 * ipc_flood_duration_ms debugfs entries atm.
149 	 * ipc_flood_count floods the DSP with the number of IPC's specified.
150 	 * ipc_duration_ms test floods the DSP for the time specified
151 	 * in the debugfs entry.
152 	 */
153 	dentry = file->f_path.dentry;
154 	if (strcmp(dentry->d_name.name, "ipc_flood_count") &&
155 	    strcmp(dentry->d_name.name, "ipc_flood_duration_ms"))
156 		return -EINVAL;
157 
158 	if (!strcmp(dentry->d_name.name, "ipc_flood_duration_ms"))
159 		flood_duration_test = true;
160 
161 	/* test completion criterion */
162 	if (flood_duration_test)
163 		ret = kstrtoul(string, 0, &ipc_duration_ms);
164 	else
165 		ret = kstrtoul(string, 0, &ipc_count);
166 	if (ret < 0)
167 		goto out;
168 
169 	/* limit max duration/ipc count for flood test */
170 	if (flood_duration_test) {
171 		if (!ipc_duration_ms) {
172 			ret = size;
173 			goto out;
174 		}
175 
176 		/* find the minimum. min() is not used to avoid warnings */
177 		if (ipc_duration_ms > MAX_IPC_FLOOD_DURATION_MS)
178 			ipc_duration_ms = MAX_IPC_FLOOD_DURATION_MS;
179 	} else {
180 		if (!ipc_count) {
181 			ret = size;
182 			goto out;
183 		}
184 
185 		/* find the minimum. min() is not used to avoid warnings */
186 		if (ipc_count > MAX_IPC_FLOOD_COUNT)
187 			ipc_count = MAX_IPC_FLOOD_COUNT;
188 	}
189 
190 	ret = pm_runtime_get_sync(sdev->dev);
191 	if (ret < 0) {
192 		dev_err_ratelimited(sdev->dev,
193 				    "error: debugfs write failed to resume %d\n",
194 				    ret);
195 		pm_runtime_put_noidle(sdev->dev);
196 		goto out;
197 	}
198 
199 	/* flood test */
200 	ret = sof_debug_ipc_flood_test(sdev, dfse, flood_duration_test,
201 				       ipc_duration_ms, ipc_count);
202 
203 	pm_runtime_mark_last_busy(sdev->dev);
204 	err = pm_runtime_put_autosuspend(sdev->dev);
205 	if (err < 0)
206 		dev_err_ratelimited(sdev->dev,
207 				    "error: debugfs write failed to idle %d\n",
208 				    err);
209 
210 	/* return size if test is successful */
211 	if (ret >= 0)
212 		ret = size;
213 out:
214 #endif
215 	kfree(string);
216 	return ret;
217 }
218 
219 static ssize_t sof_dfsentry_read(struct file *file, char __user *buffer,
220 				 size_t count, loff_t *ppos)
221 {
222 	struct snd_sof_dfsentry *dfse = file->private_data;
223 	struct snd_sof_dev *sdev = dfse->sdev;
224 	loff_t pos = *ppos;
225 	size_t size_ret;
226 	int skip = 0;
227 	int size;
228 	u8 *buf;
229 
230 #if IS_ENABLED(CONFIG_SND_SOC_SOF_DEBUG_IPC_FLOOD_TEST)
231 	struct dentry *dentry;
232 
233 	dentry = file->f_path.dentry;
234 	if ((!strcmp(dentry->d_name.name, "ipc_flood_count") ||
235 	     !strcmp(dentry->d_name.name, "ipc_flood_duration_ms")) &&
236 	    dfse->cache_buf) {
237 		if (*ppos)
238 			return 0;
239 
240 		count = strlen(dfse->cache_buf);
241 		size_ret = copy_to_user(buffer, dfse->cache_buf, count);
242 		if (size_ret)
243 			return -EFAULT;
244 
245 		*ppos += count;
246 		return count;
247 	}
248 #endif
249 	size = dfse->size;
250 
251 	/* validate position & count */
252 	if (pos < 0)
253 		return -EINVAL;
254 	if (pos >= size || !count)
255 		return 0;
256 	/* find the minimum. min() is not used since it adds sparse warnings */
257 	if (count > size - pos)
258 		count = size - pos;
259 
260 	/* align io read start to u32 multiple */
261 	pos = ALIGN_DOWN(pos, 4);
262 
263 	/* intermediate buffer size must be u32 multiple */
264 	size = ALIGN(count, 4);
265 
266 	/* if start position is unaligned, read extra u32 */
267 	if (unlikely(pos != *ppos)) {
268 		skip = *ppos - pos;
269 		if (pos + size + 4 < dfse->size)
270 			size += 4;
271 	}
272 
273 	buf = kzalloc(size, GFP_KERNEL);
274 	if (!buf)
275 		return -ENOMEM;
276 
277 	if (dfse->type == SOF_DFSENTRY_TYPE_IOMEM) {
278 #if IS_ENABLED(CONFIG_SND_SOC_SOF_DEBUG_ENABLE_DEBUGFS_CACHE)
279 		/*
280 		 * If the DSP is active: copy from IO.
281 		 * If the DSP is suspended:
282 		 *	- Copy from IO if the memory is always accessible.
283 		 *	- Otherwise, copy from cached buffer.
284 		 */
285 		if (pm_runtime_active(sdev->dev) ||
286 		    dfse->access_type == SOF_DEBUGFS_ACCESS_ALWAYS) {
287 			memcpy_fromio(buf, dfse->io_mem + pos, size);
288 		} else {
289 			dev_info(sdev->dev,
290 				 "Copying cached debugfs data\n");
291 			memcpy(buf, dfse->cache_buf + pos, size);
292 		}
293 #else
294 		/* if the DSP is in D3 */
295 		if (!pm_runtime_active(sdev->dev) &&
296 		    dfse->access_type == SOF_DEBUGFS_ACCESS_D0_ONLY) {
297 			dev_err(sdev->dev,
298 				"error: debugfs entry cannot be read in DSP D3\n");
299 			kfree(buf);
300 			return -EINVAL;
301 		}
302 
303 		memcpy_fromio(buf, dfse->io_mem + pos, size);
304 #endif
305 	} else {
306 		memcpy(buf, ((u8 *)(dfse->buf) + pos), size);
307 	}
308 
309 	/* copy to userspace */
310 	size_ret = copy_to_user(buffer, buf + skip, count);
311 
312 	kfree(buf);
313 
314 	/* update count & position if copy succeeded */
315 	if (size_ret)
316 		return -EFAULT;
317 
318 	*ppos = pos + count;
319 
320 	return count;
321 }
322 
323 static const struct file_operations sof_dfs_fops = {
324 	.open = simple_open,
325 	.read = sof_dfsentry_read,
326 	.llseek = default_llseek,
327 	.write = sof_dfsentry_write,
328 };
329 
330 /* create FS entry for debug files that can expose DSP memories, registers */
331 int snd_sof_debugfs_io_item(struct snd_sof_dev *sdev,
332 			    void __iomem *base, size_t size,
333 			    const char *name,
334 			    enum sof_debugfs_access_type access_type)
335 {
336 	struct snd_sof_dfsentry *dfse;
337 
338 	if (!sdev)
339 		return -EINVAL;
340 
341 	dfse = devm_kzalloc(sdev->dev, sizeof(*dfse), GFP_KERNEL);
342 	if (!dfse)
343 		return -ENOMEM;
344 
345 	dfse->type = SOF_DFSENTRY_TYPE_IOMEM;
346 	dfse->io_mem = base;
347 	dfse->size = size;
348 	dfse->sdev = sdev;
349 	dfse->access_type = access_type;
350 
351 #if IS_ENABLED(CONFIG_SND_SOC_SOF_DEBUG_ENABLE_DEBUGFS_CACHE)
352 	/*
353 	 * allocate cache buffer that will be used to save the mem window
354 	 * contents prior to suspend
355 	 */
356 	if (access_type == SOF_DEBUGFS_ACCESS_D0_ONLY) {
357 		dfse->cache_buf = devm_kzalloc(sdev->dev, size, GFP_KERNEL);
358 		if (!dfse->cache_buf)
359 			return -ENOMEM;
360 	}
361 #endif
362 
363 	debugfs_create_file(name, 0444, sdev->debugfs_root, dfse,
364 			    &sof_dfs_fops);
365 
366 	/* add to dfsentry list */
367 	list_add(&dfse->list, &sdev->dfsentry_list);
368 
369 	return 0;
370 }
371 EXPORT_SYMBOL_GPL(snd_sof_debugfs_io_item);
372 
373 /* create FS entry for debug files to expose kernel memory */
374 int snd_sof_debugfs_buf_item(struct snd_sof_dev *sdev,
375 			     void *base, size_t size,
376 			     const char *name, mode_t mode)
377 {
378 	struct snd_sof_dfsentry *dfse;
379 
380 	if (!sdev)
381 		return -EINVAL;
382 
383 	dfse = devm_kzalloc(sdev->dev, sizeof(*dfse), GFP_KERNEL);
384 	if (!dfse)
385 		return -ENOMEM;
386 
387 	dfse->type = SOF_DFSENTRY_TYPE_BUF;
388 	dfse->buf = base;
389 	dfse->size = size;
390 	dfse->sdev = sdev;
391 
392 #if IS_ENABLED(CONFIG_SND_SOC_SOF_DEBUG_IPC_FLOOD_TEST)
393 	/*
394 	 * cache_buf is unused for SOF_DFSENTRY_TYPE_BUF debugfs entries.
395 	 * So, use it to save the results of the last IPC flood test.
396 	 */
397 	dfse->cache_buf = devm_kzalloc(sdev->dev, IPC_FLOOD_TEST_RESULT_LEN,
398 				       GFP_KERNEL);
399 	if (!dfse->cache_buf)
400 		return -ENOMEM;
401 #endif
402 
403 	debugfs_create_file(name, mode, sdev->debugfs_root, dfse,
404 			    &sof_dfs_fops);
405 	/* add to dfsentry list */
406 	list_add(&dfse->list, &sdev->dfsentry_list);
407 
408 	return 0;
409 }
410 EXPORT_SYMBOL_GPL(snd_sof_debugfs_buf_item);
411 
412 int snd_sof_dbg_init(struct snd_sof_dev *sdev)
413 {
414 	const struct snd_sof_dsp_ops *ops = sof_ops(sdev);
415 	const struct snd_sof_debugfs_map *map;
416 	int i;
417 	int err;
418 
419 	/* use "sof" as top level debugFS dir */
420 	sdev->debugfs_root = debugfs_create_dir("sof", NULL);
421 
422 	/* init dfsentry list */
423 	INIT_LIST_HEAD(&sdev->dfsentry_list);
424 
425 	/* create debugFS files for platform specific MMIO/DSP memories */
426 	for (i = 0; i < ops->debug_map_count; i++) {
427 		map = &ops->debug_map[i];
428 
429 		err = snd_sof_debugfs_io_item(sdev, sdev->bar[map->bar] +
430 					      map->offset, map->size,
431 					      map->name, map->access_type);
432 		/* errors are only due to memory allocation, not debugfs */
433 		if (err < 0)
434 			return err;
435 	}
436 
437 #if IS_ENABLED(CONFIG_SND_SOC_SOF_DEBUG_IPC_FLOOD_TEST)
438 	/* create read-write ipc_flood_count debugfs entry */
439 	err = snd_sof_debugfs_buf_item(sdev, NULL, 0,
440 				       "ipc_flood_count", 0666);
441 
442 	/* errors are only due to memory allocation, not debugfs */
443 	if (err < 0)
444 		return err;
445 
446 	/* create read-write ipc_flood_duration_ms debugfs entry */
447 	err = snd_sof_debugfs_buf_item(sdev, NULL, 0,
448 				       "ipc_flood_duration_ms", 0666);
449 
450 	/* errors are only due to memory allocation, not debugfs */
451 	if (err < 0)
452 		return err;
453 #endif
454 
455 	return 0;
456 }
457 EXPORT_SYMBOL_GPL(snd_sof_dbg_init);
458 
459 void snd_sof_free_debug(struct snd_sof_dev *sdev)
460 {
461 	debugfs_remove_recursive(sdev->debugfs_root);
462 }
463 EXPORT_SYMBOL_GPL(snd_sof_free_debug);
464