linux/drivers/remoteproc/remoteproc_debugfs.c
Matt Redfearn fd50d8c061 remoteproc: debugfs: Remove state entry which is duplicated is sysfs
Since there is now an always available state file in sysfs with the same
function as this one in debugfs, remove the redundant entry.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
2016-10-31 17:24:48 -07:00

216 lines
6.1 KiB
C

/*
* 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>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#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;
/*
* 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_mem_entry *trace = filp->private_data;
int len = strnlen(trace->va, trace->len);
return simple_read_from_buffer(userbuf, count, ppos, trace->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)) {
rproc->recovery_disabled = false;
/* if rproc has crashed, trigger recovery */
if (rproc->state == RPROC_CRASHED)
rproc_trigger_recovery(rproc);
} else if (!strncmp(buf, "disabled", count)) {
rproc->recovery_disabled = true;
} else if (!strncmp(buf, "recover", count)) {
/* if rproc has crashed, trigger recovery */
if (rproc->state == RPROC_CRASHED)
rproc_trigger_recovery(rproc);
}
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,
};
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_mem_entry *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)
{
if (!rproc->dbg_dir)
return;
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", 0400, rproc->dbg_dir,
rproc, &rproc_recovery_ops);
}
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);
}