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  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
 11#include <linux/debugfs.h>
 12#include <linux/sched/signal.h>
 13#include "sof-priv.h"
 14#include "ops.h"
 15
 16static size_t sof_trace_avail(struct snd_sof_dev *sdev,
 17			      loff_t pos, size_t buffer_size)
 18{
 19	loff_t host_offset = READ_ONCE(sdev->host_offset);
 20
 21	/*
 22	 * If host offset is less than local pos, it means write pointer of
 23	 * host DMA buffer has been wrapped. We should output the trace data
 24	 * at the end of host DMA buffer at first.
 25	 */
 26	if (host_offset < pos)
 27		return buffer_size - pos;
 28
 29	/* If there is available trace data now, it is unnecessary to wait. */
 30	if (host_offset > pos)
 31		return host_offset - pos;
 32
 33	return 0;
 34}
 35
 36static size_t sof_wait_trace_avail(struct snd_sof_dev *sdev,
 37				   loff_t pos, size_t buffer_size)
 38{
 39	wait_queue_entry_t wait;
 40	size_t ret = sof_trace_avail(sdev, pos, buffer_size);
 41
 42	/* data immediately available */
 43	if (ret)
 44		return ret;
 45
 46	if (!sdev->dtrace_is_enabled && sdev->dtrace_draining) {
 47		/*
 48		 * tracing has ended and all traces have been
 49		 * read by client, return EOF
 50		 */
 51		sdev->dtrace_draining = false;
 52		return 0;
 53	}
 54
 55	/* wait for available trace data from FW */
 56	init_waitqueue_entry(&wait, current);
 57	set_current_state(TASK_INTERRUPTIBLE);
 58	add_wait_queue(&sdev->trace_sleep, &wait);
 59
 60	if (!signal_pending(current)) {
 61		/* set timeout to max value, no error code */
 62		schedule_timeout(MAX_SCHEDULE_TIMEOUT);
 63	}
 64	remove_wait_queue(&sdev->trace_sleep, &wait);
 65
 66	return sof_trace_avail(sdev, pos, buffer_size);
 67}
 68
 69static ssize_t sof_dfsentry_trace_read(struct file *file, char __user *buffer,
 70				       size_t count, loff_t *ppos)
 71{
 72	struct snd_sof_dfsentry *dfse = file->private_data;
 73	struct snd_sof_dev *sdev = dfse->sdev;
 74	unsigned long rem;
 75	loff_t lpos = *ppos;
 76	size_t avail, buffer_size = dfse->size;
 77	u64 lpos_64;
 78
 79	/* make sure we know about any failures on the DSP side */
 80	sdev->dtrace_error = false;
 81
 82	/* check pos and count */
 83	if (lpos < 0)
 84		return -EINVAL;
 85	if (!count)
 86		return 0;
 87
 88	/* check for buffer wrap and count overflow */
 89	lpos_64 = lpos;
 90	lpos = do_div(lpos_64, buffer_size);
 91
 92	if (count > buffer_size - lpos) /* min() not used to avoid sparse warnings */
 93		count = buffer_size - lpos;
 94
 95	/* get available count based on current host offset */
 96	avail = sof_wait_trace_avail(sdev, lpos, buffer_size);
 97	if (sdev->dtrace_error) {
 98		dev_err(sdev->dev, "error: trace IO error\n");
 99		return -EIO;
100	}
101
102	/* make sure count is <= avail */
103	count = avail > count ? count : avail;
104
105	/* copy available trace data to debugfs */
106	rem = copy_to_user(buffer, ((u8 *)(dfse->buf) + lpos), count);
107	if (rem)
108		return -EFAULT;
109
110	*ppos += count;
111
112	/* move debugfs reading position */
113	return count;
114}
115
116static int sof_dfsentry_trace_release(struct inode *inode, struct file *file)
117{
118	struct snd_sof_dfsentry *dfse = inode->i_private;
119	struct snd_sof_dev *sdev = dfse->sdev;
120
121	/* avoid duplicate traces at next open */
122	if (!sdev->dtrace_is_enabled)
123		sdev->host_offset = 0;
124
125	return 0;
126}
127
128static const struct file_operations sof_dfs_trace_fops = {
129	.open = simple_open,
130	.read = sof_dfsentry_trace_read,
131	.llseek = default_llseek,
132	.release = sof_dfsentry_trace_release,
133};
134
135static int trace_debugfs_create(struct snd_sof_dev *sdev)
136{
137	struct snd_sof_dfsentry *dfse;
138
139	if (!sdev)
140		return -EINVAL;
141
142	dfse = devm_kzalloc(sdev->dev, sizeof(*dfse), GFP_KERNEL);
143	if (!dfse)
144		return -ENOMEM;
145
146	dfse->type = SOF_DFSENTRY_TYPE_BUF;
147	dfse->buf = sdev->dmatb.area;
148	dfse->size = sdev->dmatb.bytes;
149	dfse->sdev = sdev;
150
151	debugfs_create_file("trace", 0444, sdev->debugfs_root, dfse,
152			    &sof_dfs_trace_fops);
153
154	return 0;
155}
156
157int snd_sof_init_trace_ipc(struct snd_sof_dev *sdev)
158{
159	struct sof_ipc_fw_ready *ready = &sdev->fw_ready;
160	struct sof_ipc_fw_version *v = &ready->version;
161	struct sof_ipc_dma_trace_params_ext params;
162	struct sof_ipc_reply ipc_reply;
163	int ret;
164
165	if (sdev->dtrace_is_enabled || !sdev->dma_trace_pages)
166		return -EINVAL;
167
168	/* set IPC parameters */
169	params.hdr.cmd = SOF_IPC_GLB_TRACE_MSG;
170	/* PARAMS_EXT is only supported from ABI 3.7.0 onwards */
171	if (v->abi_version >= SOF_ABI_VER(3, 7, 0)) {
172		params.hdr.size = sizeof(struct sof_ipc_dma_trace_params_ext);
173		params.hdr.cmd |= SOF_IPC_TRACE_DMA_PARAMS_EXT;
174		params.timestamp_ns = ktime_get(); /* in nanosecond */
175	} else {
176		params.hdr.size = sizeof(struct sof_ipc_dma_trace_params);
177		params.hdr.cmd |= SOF_IPC_TRACE_DMA_PARAMS;
178	}
179	params.buffer.phy_addr = sdev->dmatp.addr;
180	params.buffer.size = sdev->dmatb.bytes;
181	params.buffer.pages = sdev->dma_trace_pages;
182	params.stream_tag = 0;
183
184	sdev->host_offset = 0;
185	sdev->dtrace_draining = false;
186
187	ret = snd_sof_dma_trace_init(sdev, &params.stream_tag);
188	if (ret < 0) {
189		dev_err(sdev->dev,
190			"error: fail in snd_sof_dma_trace_init %d\n", ret);
191		return ret;
192	}
193	dev_dbg(sdev->dev, "stream_tag: %d\n", params.stream_tag);
194
195	/* send IPC to the DSP */
196	ret = sof_ipc_tx_message(sdev->ipc,
197				 params.hdr.cmd, &params, sizeof(params),
198				 &ipc_reply, sizeof(ipc_reply));
199	if (ret < 0) {
200		dev_err(sdev->dev,
201			"error: can't set params for DMA for trace %d\n", ret);
202		goto trace_release;
203	}
204
205	ret = snd_sof_dma_trace_trigger(sdev, SNDRV_PCM_TRIGGER_START);
206	if (ret < 0) {
207		dev_err(sdev->dev,
208			"error: snd_sof_dma_trace_trigger: start: %d\n", ret);
209		goto trace_release;
210	}
211
212	sdev->dtrace_is_enabled = true;
213
214	return 0;
215
216trace_release:
217	snd_sof_dma_trace_release(sdev);
218	return ret;
219}
220
221int snd_sof_init_trace(struct snd_sof_dev *sdev)
222{
223	int ret;
224
225	/* set false before start initialization */
226	sdev->dtrace_is_enabled = false;
227
228	/* allocate trace page table buffer */
229	ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, sdev->dev,
230				  PAGE_SIZE, &sdev->dmatp);
231	if (ret < 0) {
232		dev_err(sdev->dev,
233			"error: can't alloc page table for trace %d\n", ret);
234		return ret;
235	}
236
237	/* allocate trace data buffer */
238	ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV_SG, sdev->dev,
239				  DMA_BUF_SIZE_FOR_TRACE, &sdev->dmatb);
240	if (ret < 0) {
241		dev_err(sdev->dev,
242			"error: can't alloc buffer for trace %d\n", ret);
243		goto page_err;
244	}
245
246	/* create compressed page table for audio firmware */
247	ret = snd_sof_create_page_table(sdev, &sdev->dmatb, sdev->dmatp.area,
248					sdev->dmatb.bytes);
249	if (ret < 0)
250		goto table_err;
251
252	sdev->dma_trace_pages = ret;
253	dev_dbg(sdev->dev, "dma_trace_pages: %d\n", sdev->dma_trace_pages);
254
255	if (sdev->first_boot) {
256		ret = trace_debugfs_create(sdev);
257		if (ret < 0)
258			goto table_err;
259	}
260
261	init_waitqueue_head(&sdev->trace_sleep);
262
263	ret = snd_sof_init_trace_ipc(sdev);
264	if (ret < 0)
265		goto table_err;
266
267	return 0;
268table_err:
269	sdev->dma_trace_pages = 0;
270	snd_dma_free_pages(&sdev->dmatb);
271page_err:
272	snd_dma_free_pages(&sdev->dmatp);
273	return ret;
274}
275EXPORT_SYMBOL(snd_sof_init_trace);
276
277int snd_sof_trace_update_pos(struct snd_sof_dev *sdev,
278			     struct sof_ipc_dma_trace_posn *posn)
279{
280	if (sdev->dtrace_is_enabled && sdev->host_offset != posn->host_offset) {
281		sdev->host_offset = posn->host_offset;
282		wake_up(&sdev->trace_sleep);
283	}
284
285	if (posn->overflow != 0)
286		dev_err(sdev->dev,
287			"error: DSP trace buffer overflow %u bytes. Total messages %d\n",
288			posn->overflow, posn->messages);
289
290	return 0;
291}
292
293/* an error has occurred within the DSP that prevents further trace */
294void snd_sof_trace_notify_for_error(struct snd_sof_dev *sdev)
295{
296	if (sdev->dtrace_is_enabled) {
297		dev_err(sdev->dev, "error: waking up any trace sleepers\n");
298		sdev->dtrace_error = true;
299		wake_up(&sdev->trace_sleep);
300	}
301}
302EXPORT_SYMBOL(snd_sof_trace_notify_for_error);
303
304void snd_sof_release_trace(struct snd_sof_dev *sdev)
305{
306	int ret;
307
308	if (!sdev->dtrace_is_enabled)
309		return;
310
311	ret = snd_sof_dma_trace_trigger(sdev, SNDRV_PCM_TRIGGER_STOP);
312	if (ret < 0)
313		dev_err(sdev->dev,
314			"error: snd_sof_dma_trace_trigger: stop: %d\n", ret);
315
316	ret = snd_sof_dma_trace_release(sdev);
317	if (ret < 0)
318		dev_err(sdev->dev,
319			"error: fail in snd_sof_dma_trace_release %d\n", ret);
320
321	sdev->dtrace_is_enabled = false;
322	sdev->dtrace_draining = true;
323	wake_up(&sdev->trace_sleep);
324}
325EXPORT_SYMBOL(snd_sof_release_trace);
326
327void snd_sof_free_trace(struct snd_sof_dev *sdev)
328{
329	snd_sof_release_trace(sdev);
330
331	snd_dma_free_pages(&sdev->dmatb);
332	snd_dma_free_pages(&sdev->dmatp);
333}
334EXPORT_SYMBOL(snd_sof_free_trace);
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