// SPDX-License-Identifier: GPL-2.0-only
/*
* Remote Processor Framework
*
* Copyright (C) 2011 Texas Instruments, Inc.
* Copyright (C) 2011 Google, Inc.
*
* Ohad Ben-Cohen <[email protected]>
* Mark Grosen <[email protected]>
* Brian Swetland <[email protected]>
* Fernando Guzman Lugo <[email protected]>
* Suman Anna <[email protected]>
* Robert Tivy <[email protected]>
* Armando Uribe De Leon <[email protected]>
*/
#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, NULL);
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)
{
return debugfs_create_file(name, 0400, rproc->dbg_dir, trace,
&trace_rproc_ops);
}
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);
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);
}
void __exit rproc_exit_debugfs(void)
{
debugfs_remove(rproc_dbg);
}
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