Add a trace event buffer that can be used by userspace to read DSP runtime trace events alongside bespoke trace data in realtime for firmware debug.
Signed-off-by: Liam Girdwood liam.r.girdwood@linux.intel.com --- sound/soc/sof/trace.c | 279 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 279 insertions(+) create mode 100644 sound/soc/sof/trace.c
diff --git a/sound/soc/sof/trace.c b/sound/soc/sof/trace.c new file mode 100644 index 000000000000..04acd78f13be --- /dev/null +++ b/sound/soc/sof/trace.c @@ -0,0 +1,279 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) +/* + * This file is provided under a dual BSD/GPLv2 license. When using or + * redistributing this file, you may do so under either license. + * + * Copyright(c) 2017 Intel Corporation. All rights reserved. + * + * Author: Liam Girdwood liam.r.girdwood@linux.intel.com + * Yan Wang yan.wan@linux.intel.com + */ + +#include <linux/delay.h> +#include <linux/fs.h> +#include <linux/slab.h> +#include <linux/sched/signal.h> +#include <linux/time.h> +#include <linux/device.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/dma-mapping.h> +#include <linux/platform_device.h> +#include <linux/firmware.h> +#include <linux/debugfs.h> +#include <uapi/sound/sof-ipc.h> +#include <uapi/sound/sof-fw.h> +#include "sof-priv.h" +#include "ops.h" + +static size_t sof_wait_trace_avail(struct snd_sof_dev *sdev, + loff_t pos, size_t buffer_size) +{ + wait_queue_entry_t wait; + + /* + * If host offset is less than local pos, it means write pointer of + * host DMA buffer has been wrapped. We should output the trace data + * at the end of host DMA buffer at first. + */ + if (sdev->host_offset < pos) + return buffer_size - pos; + + /* If there is available trace data now, it is unnecessary to wait. */ + if (sdev->host_offset > pos) + return sdev->host_offset - pos; + + /* wait for available trace data from FW */ + init_waitqueue_entry(&wait, current); + set_current_state(TASK_INTERRUPTIBLE); + add_wait_queue(&sdev->trace_sleep, &wait); + + if (signal_pending(current)) { + remove_wait_queue(&sdev->trace_sleep, &wait); + goto out; + } + + /* set timeout to max value, no error code */ + schedule_timeout(MAX_SCHEDULE_TIMEOUT); + remove_wait_queue(&sdev->trace_sleep, &wait); + +out: + /* return bytes available for copy */ + if (sdev->host_offset < pos) + return buffer_size - pos; + else + return sdev->host_offset - pos; +} + +static ssize_t sof_dfsentry_trace_read(struct file *file, char __user *buffer, + size_t count, loff_t *ppos) +{ + struct snd_sof_dfsentry_buf *dfse = file->private_data; + struct snd_sof_dev *sdev = dfse->sdev; + unsigned long rem; + loff_t lpos = *ppos; + size_t avail, buffer_size = dfse->size; + + /* make sure we know about any failures on the DSP side */ + sdev->dtrace_error = false; + + /* check pos and count */ + if (lpos < 0) + return -EINVAL; + if (!count) + return 0; + + /* check for buffer wrap and count overflow */ + lpos = lpos % buffer_size; + if (count > buffer_size - lpos) + count = buffer_size - lpos; + + /* get available count based on current host offset */ + avail = sof_wait_trace_avail(sdev, lpos, buffer_size); + if (sdev->dtrace_error) { + dev_err(sdev->dev, "error: trace IO error\n"); + return -EIO; + } + + /* make sure count is <= avail */ + count = avail > count ? count : avail; + + /* copy available trace data to debugfs */ + rem = copy_to_user(buffer, dfse->buf + lpos, count); + if (rem == count) + return -EFAULT; + + *ppos += count; + + /* move debugfs reading position */ + return count; +} + +static const struct file_operations sof_dfs_trace_fops = { + .open = simple_open, + .read = sof_dfsentry_trace_read, + .llseek = default_llseek, +}; + +static int trace_debugfs_create(struct snd_sof_dev *sdev) +{ + struct snd_sof_dfsentry_buf *dfse; + + if (!sdev) + return -EINVAL; + + dfse = kzalloc(sizeof(*dfse), GFP_KERNEL); + if (!dfse) + return -ENOMEM; + + dfse->buf = sdev->dmatb.area; + dfse->size = sdev->dmatb.bytes; + dfse->sdev = sdev; + + dfse->dfsentry = debugfs_create_file("trace", 0444, sdev->debugfs_root, + dfse, &sof_dfs_trace_fops); + if (!dfse->dfsentry) { + dev_err(sdev->dev, + "error: cannot create debugfs entry for trace\n"); + kfree(dfse); + return -ENODEV; + } + + return 0; +} + +int snd_sof_init_trace(struct snd_sof_dev *sdev) +{ + struct sof_ipc_dma_trace_params params; + struct sof_ipc_reply ipc_reply; + int ret; + + /* set false before start initialization */ + sdev->dtrace_is_enabled = false; + + /* allocate trace page table buffer */ + ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, sdev->parent, + PAGE_SIZE, &sdev->dmatp); + if (ret < 0) { + dev_err(sdev->dev, + "error: can't alloc page table for trace %d\n", ret); + return ret; + } + + /* allocate trace data buffer */ + ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV_SG, sdev->parent, + DMA_BUF_SIZE_FOR_TRACE, &sdev->dmatb); + if (ret < 0) { + dev_err(sdev->dev, + "error: can't alloc buffer for trace %d\n", ret); + goto page_err; + } + + /* craete compressed page table for audio firmware */ + ret = snd_sof_create_page_table(sdev, &sdev->dmatb, sdev->dmatp.area, + sdev->dmatb.bytes); + if (ret < 0) + goto table_err; + + sdev->dma_trace_pages = ret; + dev_dbg(sdev->dev, "dma_trace_pages: %d\n", sdev->dma_trace_pages); + + ret = trace_debugfs_create(sdev); + if (ret < 0) + goto table_err; + + /* set IPC parameters */ + params.hdr.size = sizeof(params); + params.hdr.cmd = SOF_IPC_GLB_TRACE_MSG | SOF_IPC_TRACE_DMA_PARAMS; + params.buffer.phy_addr = sdev->dmatp.addr; + params.buffer.size = sdev->dmatb.bytes; + params.buffer.offset = 0; + params.buffer.pages = sdev->dma_trace_pages; + + init_waitqueue_head(&sdev->trace_sleep); + sdev->host_offset = 0; + + ret = snd_sof_dma_trace_init(sdev, ¶ms.stream_tag); + if (ret < 0) { + dev_err(sdev->dev, + "error: fail in snd_sof_dma_trace_init %d\n", ret); + goto table_err; + } + dev_dbg(sdev->dev, "stream_tag: %d\n", params.stream_tag); + + /* send IPC to the DSP */ + ret = sof_ipc_tx_message(sdev->ipc, + params.hdr.cmd, ¶ms, sizeof(params), + &ipc_reply, sizeof(ipc_reply)); + if (ret < 0) { + dev_err(sdev->dev, + "error: can't set params for DMA for trace %d\n", ret); + goto table_err; + } + + ret = snd_sof_dma_trace_trigger(sdev, SNDRV_PCM_TRIGGER_START); + if (ret < 0) { + dev_err(sdev->dev, + "error: snd_sof_dma_trace_trigger: start: %d\n", ret); + goto table_err; + } + + sdev->dtrace_is_enabled = true; + return 0; + +table_err: + snd_dma_free_pages(&sdev->dmatb); +page_err: + snd_dma_free_pages(&sdev->dmatp); + return ret; +} +EXPORT_SYMBOL(snd_sof_init_trace); + +int snd_sof_trace_update_pos(struct snd_sof_dev *sdev, + struct sof_ipc_dma_trace_posn *posn) +{ + if (sdev->dtrace_is_enabled && sdev->host_offset != posn->host_offset) { + sdev->host_offset = posn->host_offset; + wake_up(&sdev->trace_sleep); + } + + if (posn->overflow != 0) + dev_err(sdev->dev, + "error: DSP trace buffer overflow %u bytes. Total messages %d\n", + posn->overflow, posn->messages); + + return 0; +} + +/* an error has occurred within the DSP that prevents further trace */ +void snd_sof_trace_notify_for_error(struct snd_sof_dev *sdev) +{ + if (sdev->dtrace_is_enabled) { + dev_err(sdev->dev, "error: waking up any trace sleepers\n"); + sdev->dtrace_error = true; + wake_up(&sdev->trace_sleep); + } +} +EXPORT_SYMBOL(snd_sof_trace_notify_for_error); + +void snd_sof_release_trace(struct snd_sof_dev *sdev) +{ + int ret; + + if (!sdev->dtrace_is_enabled) + return; + + ret = snd_sof_dma_trace_trigger(sdev, SNDRV_PCM_TRIGGER_STOP); + if (ret < 0) + dev_err(sdev->dev, + "error: snd_sof_dma_trace_trigger: stop: %d\n", ret); + + ret = snd_sof_dma_trace_release(sdev); + if (ret < 0) + dev_err(sdev->dev, + "error: fail in snd_sof_dma_trace_release %d\n", ret); + + snd_dma_free_pages(&sdev->dmatb); + snd_dma_free_pages(&sdev->dmatp); +} +EXPORT_SYMBOL(snd_sof_release_trace);