1 files changed, 232 insertions, 0 deletions
diff --git a/sound/soc/sof/debug.c b/sound/soc/sof/debug.c
new file mode 100644
index 000000000000..55f1d808dba0
--- /dev/null
+++ b/sound/soc/sof/debug.c
@@ -0,0 +1,232 @@
+// 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) 2018 Intel Corporation. All rights reserved.
+//
+// Author: Liam Girdwood <liam.r.girdwood@linux.intel.com>
+//
+// Generic debug routines used to export DSP MMIO and memories to userspace
+// for firmware debugging.
+//
+
+#include <linux/debugfs.h>
+#include <linux/io.h>
+#include <linux/pm_runtime.h>
+#include "sof-priv.h"
+#include "ops.h"
+
+static ssize_t sof_dfsentry_read(struct file *file, char __user *buffer,
+				 size_t count, loff_t *ppos)
+{
+	struct snd_sof_dfsentry *dfse = file->private_data;
+	struct snd_sof_dev *sdev = dfse->sdev;
+	loff_t pos = *ppos;
+	size_t size_ret;
+	int skip = 0;
+	int size;
+	u8 *buf;
+
+	size = dfse->size;
+
+	/* validate position & count */
+	if (pos < 0)
+		return -EINVAL;
+	if (pos >= size || !count)
+		return 0;
+	/* find the minimum. min() is not used since it adds sparse warnings */
+	if (count > size - pos)
+		count = size - pos;
+
+	/* align io read start to u32 multiple */
+	pos = ALIGN_DOWN(pos, 4);
+
+	/* intermediate buffer size must be u32 multiple */
+	size = ALIGN(count, 4);
+
+	/* if start position is unaligned, read extra u32 */
+	if (unlikely(pos != *ppos)) {
+		skip = *ppos - pos;
+		if (pos + size + 4 < dfse->size)
+			size += 4;
+	}
+
+	buf = kzalloc(size, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	if (dfse->type == SOF_DFSENTRY_TYPE_IOMEM) {
+#if IS_ENABLED(CONFIG_SND_SOC_SOF_DEBUG_ENABLE_DEBUGFS_CACHE)
+		/*
+		 * If the DSP is active: copy from IO.
+		 * If the DSP is suspended:
+		 *	- Copy from IO if the memory is always accessible.
+		 *	- Otherwise, copy from cached buffer.
+		 */
+		if (pm_runtime_active(sdev->dev) ||
+		    dfse->access_type == SOF_DEBUGFS_ACCESS_ALWAYS) {
+			memcpy_fromio(buf, dfse->io_mem + pos, size);
+		} else {
+			dev_info(sdev->dev,
+				 "Copying cached debugfs data\n");
+			memcpy(buf, dfse->cache_buf + pos, size);
+		}
+#else
+		/* if the DSP is in D3 */
+		if (!pm_runtime_active(sdev->dev) &&
+		    dfse->access_type == SOF_DEBUGFS_ACCESS_D0_ONLY) {
+			dev_err(sdev->dev,
+				"error: debugfs entry %s cannot be read in DSP D3\n",
+				dfse->dfsentry->d_name.name);
+			kfree(buf);
+			return -EINVAL;
+		}
+
+		memcpy_fromio(buf, dfse->io_mem + pos, size);
+#endif
+	} else {
+		memcpy(buf, ((u8 *)(dfse->buf) + pos), size);
+	}
+
+	/* copy to userspace */
+	size_ret = copy_to_user(buffer, buf + skip, count);
+
+	kfree(buf);
+
+	/* update count & position if copy succeeded */
+	if (size_ret)
+		return -EFAULT;
+
+	*ppos = pos + count;
+
+	return count;
+}
+
+static const struct file_operations sof_dfs_fops = {
+	.open = simple_open,
+	.read = sof_dfsentry_read,
+	.llseek = default_llseek,
+};
+
+/* create FS entry for debug files that can expose DSP memories, registers */
+int snd_sof_debugfs_io_item(struct snd_sof_dev *sdev,
+			    void __iomem *base, size_t size,
+			    const char *name,
+			    enum sof_debugfs_access_type access_type)
+{
+	struct snd_sof_dfsentry *dfse;
+
+	if (!sdev)
+		return -EINVAL;
+
+	dfse = devm_kzalloc(sdev->dev, sizeof(*dfse), GFP_KERNEL);
+	if (!dfse)
+		return -ENOMEM;
+
+	dfse->type = SOF_DFSENTRY_TYPE_IOMEM;
+	dfse->io_mem = base;
+	dfse->size = size;
+	dfse->sdev = sdev;
+	dfse->access_type = access_type;
+
+#if IS_ENABLED(CONFIG_SND_SOC_SOF_DEBUG_ENABLE_DEBUGFS_CACHE)
+	/*
+	 * allocate cache buffer that will be used to save the mem window
+	 * contents prior to suspend
+	 */
+	if (access_type == SOF_DEBUGFS_ACCESS_D0_ONLY) {
+		dfse->cache_buf = devm_kzalloc(sdev->dev, size, GFP_KERNEL);
+		if (!dfse->cache_buf)
+			return -ENOMEM;
+	}
+#endif
+
+	dfse->dfsentry = debugfs_create_file(name, 0444, sdev->debugfs_root,
+					     dfse, &sof_dfs_fops);
+	if (!dfse->dfsentry) {
+		/* can't rely on debugfs, only log error and keep going */
+		dev_err(sdev->dev, "error: cannot create debugfs entry %s\n",
+			name);
+	} else {
+		/* add to dfsentry list */
+		list_add(&dfse->list, &sdev->dfsentry_list);
+
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(snd_sof_debugfs_io_item);
+
+/* create FS entry for debug files to expose kernel memory */
+int snd_sof_debugfs_buf_item(struct snd_sof_dev *sdev,
+			     void *base, size_t size,
+			     const char *name)
+{
+	struct snd_sof_dfsentry *dfse;
+
+	if (!sdev)
+		return -EINVAL;
+
+	dfse = devm_kzalloc(sdev->dev, sizeof(*dfse), GFP_KERNEL);
+	if (!dfse)
+		return -ENOMEM;
+
+	dfse->type = SOF_DFSENTRY_TYPE_BUF;
+	dfse->buf = base;
+	dfse->size = size;
+	dfse->sdev = sdev;
+
+	dfse->dfsentry = debugfs_create_file(name, 0444, sdev->debugfs_root,
+					     dfse, &sof_dfs_fops);
+	if (!dfse->dfsentry) {
+		/* can't rely on debugfs, only log error and keep going */
+		dev_err(sdev->dev, "error: cannot create debugfs entry %s\n",
+			name);
+	} else {
+		/* add to dfsentry list */
+		list_add(&dfse->list, &sdev->dfsentry_list);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(snd_sof_debugfs_buf_item);
+
+int snd_sof_dbg_init(struct snd_sof_dev *sdev)
+{
+	const struct snd_sof_dsp_ops *ops = sof_ops(sdev);
+	const struct snd_sof_debugfs_map *map;
+	int i;
+	int err;
+
+	/* use "sof" as top level debugFS dir */
+	sdev->debugfs_root = debugfs_create_dir("sof", NULL);
+	if (IS_ERR_OR_NULL(sdev->debugfs_root)) {
+		dev_err(sdev->dev, "error: failed to create debugfs directory\n");
+		return 0;
+	}
+
+	/* init dfsentry list */
+	INIT_LIST_HEAD(&sdev->dfsentry_list);
+
+	/* create debugFS files for platform specific MMIO/DSP memories */
+	for (i = 0; i < ops->debug_map_count; i++) {
+		map = &ops->debug_map[i];
+
+		err = snd_sof_debugfs_io_item(sdev, sdev->bar[map->bar] +
+					      map->offset, map->size,
+					      map->name, map->access_type);
+		/* errors are only due to memory allocation, not debugfs */
+		if (err < 0)
+			return err;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(snd_sof_dbg_init);
+
+void snd_sof_free_debug(struct snd_sof_dev *sdev)
+{
+	debugfs_remove_recursive(sdev->debugfs_root);
+}
+EXPORT_SYMBOL_GPL(snd_sof_free_debug);