1 files changed, 443 insertions, 0 deletions

diff --git a/drivers/remoteproc/remoteproc_debugfs.c b/drivers/remoteproc/remoteproc_debugfs.c
new file mode 100644
index 000000000..e8bb0ee6b
--- /dev/null
+++ b/drivers/remoteproc/remoteproc_debugfs.c
@@ -0,0 +1,443 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Remote Processor Framework
+ *
+ * Copyright (C) 2011 Texas Instruments, Inc.
+ * Copyright (C) 2011 Google, Inc.
+ *
+ * Ohad Ben-Cohen <ohad@wizery.com>
+ * Mark Grosen <mgrosen@ti.com>
+ * Brian Swetland <swetland@google.com>
+ * Fernando Guzman Lugo <fernando.lugo@ti.com>
+ * Suman Anna <s-anna@ti.com>
+ * Robert Tivy <rtivy@ti.com>
+ * Armando Uribe De Leon <x0095078@ti.com>
+ */
+
+#define pr_fmt(fmt)    "%s: " fmt, __func__
+
+#include <linux/kernel.h>
+#include <linux/debugfs.h>
+#include <linux/remoteproc.h>
+#include <linux/device.h>
+#include <linux/uaccess.h>
+
+#include "remoteproc_internal.h"
+
+/* remoteproc debugfs parent dir */
+static struct dentry *rproc_dbg;
+
+/*
+ * A coredump-configuration-to-string lookup table, for exposing a
+ * human readable configuration via debugfs. Always keep in sync with
+ * enum rproc_coredump_mechanism
+ */
+static const char * const rproc_coredump_str[] = {
+	[RPROC_COREDUMP_DISABLED]	= "disabled",
+	[RPROC_COREDUMP_ENABLED]	= "enabled",
+	[RPROC_COREDUMP_INLINE]		= "inline",
+};
+
+/* Expose the current coredump configuration via debugfs */
+static ssize_t rproc_coredump_read(struct file *filp, char __user *userbuf,
+				   size_t count, loff_t *ppos)
+{
+	struct rproc *rproc = filp->private_data;
+	char buf[20];
+	int len;
+
+	len = scnprintf(buf, sizeof(buf), "%s\n",
+			rproc_coredump_str[rproc->dump_conf]);
+
+	return simple_read_from_buffer(userbuf, count, ppos, buf, len);
+}
+
+/*
+ * By writing to the 'coredump' debugfs entry, we control the behavior of the
+ * coredump mechanism dynamically. The default value of this entry is "disabled".
+ *
+ * The 'coredump' debugfs entry supports these commands:
+ *
+ * disabled:	By default coredump collection is disabled. Recovery will
+ *		proceed without collecting any dump.
+ *
+ * enabled:	When the remoteproc crashes the entire coredump will be copied
+ *		to a separate buffer and exposed to userspace.
+ *
+ * inline:	The coredump will not be copied to a separate buffer and the
+ *		recovery process will have to wait until data is read by
+ *		userspace. But this avoid usage of extra memory.
+ */
+static ssize_t rproc_coredump_write(struct file *filp,
+				    const char __user *user_buf, size_t count,
+				    loff_t *ppos)
+{
+	struct rproc *rproc = filp->private_data;
+	int ret, err = 0;
+	char buf[20];
+
+	if (count < 1 || count > sizeof(buf))
+		return -EINVAL;
+
+	ret = copy_from_user(buf, user_buf, count);
+	if (ret)
+		return -EFAULT;
+
+	/* remove end of line */
+	if (buf[count - 1] == '\n')
+		buf[count - 1] = '\0';
+
+	if (rproc->state == RPROC_CRASHED) {
+		dev_err(&rproc->dev, "can't change coredump configuration\n");
+		err = -EBUSY;
+		goto out;
+	}
+
+	if (!strncmp(buf, "disabled", count)) {
+		rproc->dump_conf = RPROC_COREDUMP_DISABLED;
+	} else if (!strncmp(buf, "enabled", count)) {
+		rproc->dump_conf = RPROC_COREDUMP_ENABLED;
+	} else if (!strncmp(buf, "inline", count)) {
+		rproc->dump_conf = RPROC_COREDUMP_INLINE;
+	} else {
+		dev_err(&rproc->dev, "Invalid coredump configuration\n");
+		err = -EINVAL;
+	}
+out:
+	return err ? err : count;
+}
+
+static const struct file_operations rproc_coredump_fops = {
+	.read = rproc_coredump_read,
+	.write = rproc_coredump_write,
+	.open = simple_open,
+	.llseek = generic_file_llseek,
+};
+
+/*
+ * Some remote processors may support dumping trace logs into a shared
+ * memory buffer. We expose this trace buffer using debugfs, so users
+ * can easily tell what's going on remotely.
+ *
+ * We will most probably improve the rproc tracing facilities later on,
+ * but this kind of lightweight and simple mechanism is always good to have,
+ * as it provides very early tracing with little to no dependencies at all.
+ */
+static ssize_t rproc_trace_read(struct file *filp, char __user *userbuf,
+				size_t count, loff_t *ppos)
+{
+	struct rproc_debug_trace *data = filp->private_data;
+	struct rproc_mem_entry *trace = &data->trace_mem;
+	void *va;
+	char buf[100];
+	int len;
+
+	va = rproc_da_to_va(data->rproc, trace->da, trace->len);
+
+	if (!va) {
+		len = scnprintf(buf, sizeof(buf), "Trace %s not available\n",
+				trace->name);
+		va = buf;
+	} else {
+		len = strnlen(va, trace->len);
+	}
+
+	return simple_read_from_buffer(userbuf, count, ppos, va, len);
+}
+
+static const struct file_operations trace_rproc_ops = {
+	.read = rproc_trace_read,
+	.open = simple_open,
+	.llseek	= generic_file_llseek,
+};
+
+/* expose the name of the remote processor via debugfs */
+static ssize_t rproc_name_read(struct file *filp, char __user *userbuf,
+			       size_t count, loff_t *ppos)
+{
+	struct rproc *rproc = filp->private_data;
+	/* need room for the name, a newline and a terminating null */
+	char buf[100];
+	int i;
+
+	i = scnprintf(buf, sizeof(buf), "%.98s\n", rproc->name);
+
+	return simple_read_from_buffer(userbuf, count, ppos, buf, i);
+}
+
+static const struct file_operations rproc_name_ops = {
+	.read = rproc_name_read,
+	.open = simple_open,
+	.llseek	= generic_file_llseek,
+};
+
+/* expose recovery flag via debugfs */
+static ssize_t rproc_recovery_read(struct file *filp, char __user *userbuf,
+				   size_t count, loff_t *ppos)
+{
+	struct rproc *rproc = filp->private_data;
+	char *buf = rproc->recovery_disabled ? "disabled\n" : "enabled\n";
+
+	return simple_read_from_buffer(userbuf, count, ppos, buf, strlen(buf));
+}
+
+/*
+ * By writing to the 'recovery' debugfs entry, we control the behavior of the
+ * recovery mechanism dynamically. The default value of this entry is "enabled".
+ *
+ * The 'recovery' debugfs entry supports these commands:
+ *
+ * enabled:	When enabled, the remote processor will be automatically
+ *		recovered whenever it crashes. Moreover, if the remote
+ *		processor crashes while recovery is disabled, it will
+ *		be automatically recovered too as soon as recovery is enabled.
+ *
+ * disabled:	When disabled, a remote processor will remain in a crashed
+ *		state if it crashes. This is useful for debugging purposes;
+ *		without it, debugging a crash is substantially harder.
+ *
+ * recover:	This function will trigger an immediate recovery if the
+ *		remote processor is in a crashed state, without changing
+ *		or checking the recovery state (enabled/disabled).
+ *		This is useful during debugging sessions, when one expects
+ *		additional crashes to happen after enabling recovery. In this
+ *		case, enabling recovery will make it hard to debug subsequent
+ *		crashes, so it's recommended to keep recovery disabled, and
+ *		instead use the "recover" command as needed.
+ */
+static ssize_t
+rproc_recovery_write(struct file *filp, const char __user *user_buf,
+		     size_t count, loff_t *ppos)
+{
+	struct rproc *rproc = filp->private_data;
+	char buf[10];
+	int ret;
+
+	if (count < 1 || count > sizeof(buf))
+		return -EINVAL;
+
+	ret = copy_from_user(buf, user_buf, count);
+	if (ret)
+		return -EFAULT;
+
+	/* remove end of line */
+	if (buf[count - 1] == '\n')
+		buf[count - 1] = '\0';
+
+	if (!strncmp(buf, "enabled", count)) {
+		/* change the flag and begin the recovery process if needed */
+		rproc->recovery_disabled = false;
+		rproc_trigger_recovery(rproc);
+	} else if (!strncmp(buf, "disabled", count)) {
+		rproc->recovery_disabled = true;
+	} else if (!strncmp(buf, "recover", count)) {
+		/* begin the recovery process without changing the flag */
+		rproc_trigger_recovery(rproc);
+	} else {
+		return -EINVAL;
+	}
+
+	return count;
+}
+
+static const struct file_operations rproc_recovery_ops = {
+	.read = rproc_recovery_read,
+	.write = rproc_recovery_write,
+	.open = simple_open,
+	.llseek = generic_file_llseek,
+};
+
+/* expose the crash trigger via debugfs */
+static ssize_t
+rproc_crash_write(struct file *filp, const char __user *user_buf,
+		  size_t count, loff_t *ppos)
+{
+	struct rproc *rproc = filp->private_data;
+	unsigned int type;
+	int ret;
+
+	ret = kstrtouint_from_user(user_buf, count, 0, &type);
+	if (ret < 0)
+		return ret;
+
+	rproc_report_crash(rproc, type);
+
+	return count;
+}
+
+static const struct file_operations rproc_crash_ops = {
+	.write = rproc_crash_write,
+	.open = simple_open,
+	.llseek = generic_file_llseek,
+};
+
+/* Expose resource table content via debugfs */
+static int rproc_rsc_table_show(struct seq_file *seq, void *p)
+{
+	static const char * const types[] = {"carveout", "devmem", "trace", "vdev"};
+	struct rproc *rproc = seq->private;
+	struct resource_table *table = rproc->table_ptr;
+	struct fw_rsc_carveout *c;
+	struct fw_rsc_devmem *d;
+	struct fw_rsc_trace *t;
+	struct fw_rsc_vdev *v;
+	int i, j;
+
+	if (!table) {
+		seq_puts(seq, "No resource table found\n");
+		return 0;
+	}
+
+	for (i = 0; i < table->num; i++) {
+		int offset = table->offset[i];
+		struct fw_rsc_hdr *hdr = (void *)table + offset;
+		void *rsc = (void *)hdr + sizeof(*hdr);
+
+		switch (hdr->type) {
+		case RSC_CARVEOUT:
+			c = rsc;
+			seq_printf(seq, "Entry %d is of type %s\n", i, types[hdr->type]);
+			seq_printf(seq, "  Device Address 0x%x\n", c->da);
+			seq_printf(seq, "  Physical Address 0x%x\n", c->pa);
+			seq_printf(seq, "  Length 0x%x Bytes\n", c->len);
+			seq_printf(seq, "  Flags 0x%x\n", c->flags);
+			seq_printf(seq, "  Reserved (should be zero) [%d]\n", c->reserved);
+			seq_printf(seq, "  Name %s\n\n", c->name);
+			break;
+		case RSC_DEVMEM:
+			d = rsc;
+			seq_printf(seq, "Entry %d is of type %s\n", i, types[hdr->type]);
+			seq_printf(seq, "  Device Address 0x%x\n", d->da);
+			seq_printf(seq, "  Physical Address 0x%x\n", d->pa);
+			seq_printf(seq, "  Length 0x%x Bytes\n", d->len);
+			seq_printf(seq, "  Flags 0x%x\n", d->flags);
+			seq_printf(seq, "  Reserved (should be zero) [%d]\n", d->reserved);
+			seq_printf(seq, "  Name %s\n\n", d->name);
+			break;
+		case RSC_TRACE:
+			t = rsc;
+			seq_printf(seq, "Entry %d is of type %s\n", i, types[hdr->type]);
+			seq_printf(seq, "  Device Address 0x%x\n", t->da);
+			seq_printf(seq, "  Length 0x%x Bytes\n", t->len);
+			seq_printf(seq, "  Reserved (should be zero) [%d]\n", t->reserved);
+			seq_printf(seq, "  Name %s\n\n", t->name);
+			break;
+		case RSC_VDEV:
+			v = rsc;
+			seq_printf(seq, "Entry %d is of type %s\n", i, types[hdr->type]);
+
+			seq_printf(seq, "  ID %d\n", v->id);
+			seq_printf(seq, "  Notify ID %d\n", v->notifyid);
+			seq_printf(seq, "  Device features 0x%x\n", v->dfeatures);
+			seq_printf(seq, "  Guest features 0x%x\n", v->gfeatures);
+			seq_printf(seq, "  Config length 0x%x\n", v->config_len);
+			seq_printf(seq, "  Status 0x%x\n", v->status);
+			seq_printf(seq, "  Number of vrings %d\n", v->num_of_vrings);
+			seq_printf(seq, "  Reserved (should be zero) [%d][%d]\n\n",
+				   v->reserved[0], v->reserved[1]);
+
+			for (j = 0; j < v->num_of_vrings; j++) {
+				seq_printf(seq, "  Vring %d\n", j);
+				seq_printf(seq, "    Device Address 0x%x\n", v->vring[j].da);
+				seq_printf(seq, "    Alignment %d\n", v->vring[j].align);
+				seq_printf(seq, "    Number of buffers %d\n", v->vring[j].num);
+				seq_printf(seq, "    Notify ID %d\n", v->vring[j].notifyid);
+				seq_printf(seq, "    Physical Address 0x%x\n\n",
+					   v->vring[j].pa);
+			}
+			break;
+		default:
+			seq_printf(seq, "Unknown resource type found: %d [hdr: %pK]\n",
+				   hdr->type, hdr);
+			break;
+		}
+	}
+
+	return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(rproc_rsc_table);
+
+/* Expose carveout content via debugfs */
+static int rproc_carveouts_show(struct seq_file *seq, void *p)
+{
+	struct rproc *rproc = seq->private;
+	struct rproc_mem_entry *carveout;
+
+	list_for_each_entry(carveout, &rproc->carveouts, node) {
+		seq_puts(seq, "Carveout memory entry:\n");
+		seq_printf(seq, "\tName: %s\n", carveout->name);
+		seq_printf(seq, "\tVirtual address: %pK\n", carveout->va);
+		seq_printf(seq, "\tDMA address: %pad\n", &carveout->dma);
+		seq_printf(seq, "\tDevice address: 0x%x\n", carveout->da);
+		seq_printf(seq, "\tLength: 0x%zx Bytes\n\n", carveout->len);
+	}
+
+	return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(rproc_carveouts);
+
+void rproc_remove_trace_file(struct dentry *tfile)
+{
+	debugfs_remove(tfile);
+}
+
+struct dentry *rproc_create_trace_file(const char *name, struct rproc *rproc,
+				       struct rproc_debug_trace *trace)
+{
+	struct dentry *tfile;
+
+	tfile = debugfs_create_file(name, 0400, rproc->dbg_dir, trace,
+				    &trace_rproc_ops);
+	if (!tfile) {
+		dev_err(&rproc->dev, "failed to create debugfs trace entry\n");
+		return NULL;
+	}
+
+	return tfile;
+}
+
+void rproc_delete_debug_dir(struct rproc *rproc)
+{
+	debugfs_remove_recursive(rproc->dbg_dir);
+}
+
+void rproc_create_debug_dir(struct rproc *rproc)
+{
+	struct device *dev = &rproc->dev;
+
+	if (!rproc_dbg)
+		return;
+
+	rproc->dbg_dir = debugfs_create_dir(dev_name(dev), rproc_dbg);
+	if (!rproc->dbg_dir)
+		return;
+
+	debugfs_create_file("name", 0400, rproc->dbg_dir,
+			    rproc, &rproc_name_ops);
+	debugfs_create_file("recovery", 0600, rproc->dbg_dir,
+			    rproc, &rproc_recovery_ops);
+	debugfs_create_file("crash", 0200, rproc->dbg_dir,
+			    rproc, &rproc_crash_ops);
+	debugfs_create_file("resource_table", 0400, rproc->dbg_dir,
+			    rproc, &rproc_rsc_table_fops);
+	debugfs_create_file("carveout_memories", 0400, rproc->dbg_dir,
+			    rproc, &rproc_carveouts_fops);
+	debugfs_create_file("coredump", 0600, rproc->dbg_dir,
+			    rproc, &rproc_coredump_fops);
+}
+
+void __init rproc_init_debugfs(void)
+{
+	if (debugfs_initialized()) {
+		rproc_dbg = debugfs_create_dir(KBUILD_MODNAME, NULL);
+		if (!rproc_dbg)
+			pr_err("can't create debugfs dir\n");
+	}
+}
+
+void __exit rproc_exit_debugfs(void)
+{
+	debugfs_remove(rproc_dbg);
+}