/**
* @file klogger_393.c
* @brief Record strings with timestamps (using FPGA time) to a memory buffer (no I/O),
* Read the buffer as character device
* @copyright Copyright (C) 2016 Elphel, Inc.
* @par <b>License</b>
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/io.h>
#include <linux/errno.h>
#include <linux/platform_device.h> // For sysfs
#include <linux/slab.h> //kzalloc
#include <linux/fs.h>
#include <asm/uaccess.h> // copy_*_user
#include <linux/of.h> // Device Tree
#include <uapi/elphel/c313a.h> // PARS_FRAMES_MASK
#include <uapi/elphel/x393_devices.h> // For sysfs
#include "x393.h"
#include "x393_fpga_functions.h"
#include "klogger_393.h"
#define KLOGGER_BUFFER_ANY_SIZE 1 // any buffer size, use multiple subtractions to convert file pointer to buffer pointer
//#define DEV393_KLOGGER ("klogger_393", "klogger_393", 144, 1, "0666", "c") ///< kernel event logger to memory (no i/o)
#ifdef LOCK_BH_KLOGGER
#define FLAGS_KLOGGER_BH
#define LOCK_KLOGGER_BH(x) spin_lock_bh(x)
#define UNLOCK_KLOGGER_BH(x) spin_unlock_bh(x)
#else
#define FLAGS_KLOGGER_BH unsigned long flags;
#define LOCK_KLOGGER_BH(x) spin_lock_irqsave(x,flags)
#define UNLOCK_KLOGGER_BH(x) spin_unlock_irqrestore(x,flags)
#endif
static DEFINE_SPINLOCK(klogger_lock);
static struct device *g_dev_ptr=NULL; ///< Global pointer to basic device structure. This pointer is used in debugfs output functions
static u32 buffer_size = 0;
#ifndef KLOGGER_BUFFER_ANY_SIZE
static u32 buffer_size_order = 0;
#endif
static u32 klog_mode=0xff;
static u32 buffer_wp = 0;
static u32 num_writes = 0;
static loff_t file_size = 0; // write pointer, 64 bits
static char * klog393_buf = NULL;
const char klogger393_of_prop_bufsize_name[] = "klogger-393,buffer_size";
const static u32 max_string_len = PAGE_SIZE; ///< maximal string length
int klogger393_open(struct inode *inode, struct file *filp);
int klogger393_release(struct inode *inode, struct file *filp);
loff_t klogger393_llseek(struct file * file, loff_t offset, int orig);
ssize_t klogger393_read (struct file * file, char * buf, size_t count, loff_t *off);
// printk();
int print_klog393(const int mode, ///< bits 0: timestamp, 1 - file, 2 - function, 3 - line number, 4 - lock, irq & disable. all 0 - disabled
const char *file, /// file path to show
const char *function, /// function name to show
const int line, // line number to show
const char *fmt, ...) ///< Format and argumants as in printf
{
FLAGS_KLOGGER_BH
char buf[1024];
const char * cp;
sec_usec_t ts;
va_list args;
int mmode= mode & klog_mode;
if (!mmode){
return 0;
}
if (mmode & 16){
// spin_lock_bh(&klogger_lock);
LOCK_KLOGGER_BH(&klogger_lock);
}
if (mmode & 1) {
get_fpga_rtc(&ts);
snprintf(buf,sizeof(buf),"%ld.%06ld:",ts.sec,ts.usec);
klog393_puts(buf);
}
if ((mmode & 2) && file) {
cp = strrchr(file,'/');
cp = cp? (cp+1):file;
snprintf(buf,sizeof(buf),"%s:",cp);
klog393_puts(buf);
}
if ((mmode & 4) && function) {
snprintf(buf,sizeof(buf),"%s:",function);
klog393_puts(buf);
}
if ((mmode & 8) && line) {
snprintf(buf,sizeof(buf),"%d:",line);
klog393_puts(buf);
}
va_start(args, fmt);
vsnprintf(buf,sizeof(buf),fmt,args);
va_end(args);
klog393_puts(buf);
if (mmode & 16){
// spin_unlock_bh(&klogger_lock);
UNLOCK_KLOGGER_BH(&klogger_lock);
}
return 0;
}
/** Put string into the logger buffer*/
int klog393_puts(const char * str) ///< String to log, limited by max_string_len (currently 4096 bytes)
///< @return 0 - OK, -EMSGSIZE - string too long
{
int sl = strlen(str);
u32 new_wp= buffer_wp+sl;
if (!(klog_mode & 0x80)){
return 0; // DEBUGGING: Do nothing if bit 7 == 0
}
// u32 pl;
if (sl > max_string_len){
dev_err(g_dev_ptr,"%s: String too long (%d >%d)\n",
__func__,strlen(str), max_string_len );
return -EMSGSIZE;
}
// See if the string fits in the buffer
if (likely(new_wp < buffer_size)){
memcpy(klog393_buf+buffer_wp, str,sl);
buffer_wp = new_wp;
} else {
memcpy(klog393_buf+buffer_wp, str, buffer_size - buffer_wp);
memcpy(klog393_buf, str, sl - (buffer_size - buffer_wp));
buffer_wp = new_wp - buffer_size;
}
file_size += sl;
num_writes++;
return 0;
}
/** Put string into the logger buffer, preceded by a timestamp "<sec>.<usec>: "*/
int klog393_ts(const char * str) ///< String to log, limited by max_string_len (currently 4096 bytes)
///< @return 0 - OK, -EMSGSIZE - string too long
{
sec_usec_t ts;
char buf[20]; // 18 enough
get_fpga_rtc(&ts);
sprintf(buf,"%ld.%06ld: ",ts.sec,ts.usec);
klog393_puts(buf);
return klog393_puts(str);
}
static struct file_operations framepars_fops = {
owner: THIS_MODULE,
open: klogger393_open,
llseek: klogger393_llseek,
read: klogger393_read,
release: klogger393_release
};
/** Driver OPEN method */
int klogger393_open(struct inode *inode, ///< inode pointer
struct file *filp) ///< file pointer
///< @return OK - 0, -EINVAL for wrong minor
{
int minor= MINOR(inode->i_rdev);
filp->private_data = (int *) minor; // store just minor there
dev_dbg(g_dev_ptr,"minor=0x%x\n", minor);
switch (minor) {
case DEV393_MINOR(DEV393_KLOGGER):
inode->i_size = file_size; //or return 8 - number of frame pages?
return 0;
default:
return -EINVAL;
}
}
/** Driver RELEASE method */
int klogger393_release(struct inode *inode, ///< inode pointer
struct file *filp) ///< file pointer
///< @return OK - 0, -EINVAL for wrong minor
{
int minor= MINOR(inode->i_rdev);
switch ( minor ) {
case DEV393_MINOR(DEV393_KLOGGER):
dev_dbg(g_dev_ptr,"Release DONE, minor=0x%x\n", minor);
break;
default: return -EINVAL;
}
return 0;
}
/** Driver LLSEEK method */
loff_t klogger393_llseek(struct file * file, ///< file structure pointer
loff_t offset, ///< 64-bit offset
int orig) ///< Offset origin (SEEK_SET==0, SEEK_CUR==1, SEEK_END==2 - see fs.h)
///< @return new file position or negative error
{
int minor=(int)file->private_data;
dev_dbg(g_dev_ptr,"file=%x, offset=%llx (%d), orig=%x\r\n", (int) file, offset,(int) offset, (int) orig);
switch (minor) {
case DEV393_MINOR(DEV393_KLOGGER):
switch (orig) {
case SEEK_SET:
file->f_pos = offset;
break;
case SEEK_CUR:
file->f_pos += offset;
break;
case SEEK_END:
//!overload later?
if (offset<=0) {
file->f_pos = file_size + offset;
} else {
file->f_pos = file_size + offset; // Overload if needed as usual
}
break;
default:
dev_err(g_dev_ptr,"lseek: invalid orig=%d\n", orig);
return -EINVAL;
}
break;
default:
dev_err(g_dev_ptr,"lseek: invalid minor=%d\n", minor);
return -EINVAL;
}
/** truncate position */
if (file->f_pos < 0) {
dev_err(g_dev_ptr,"negative position: minor=%d, file->f_pos=0x%llx\n", minor, file->f_pos);
file->f_pos = 0;
return (-EOVERFLOW);
}
// No sense to output overwritten data in the buffer
if (file->f_pos < (file_size - buffer_size))
file->f_pos = (file_size - buffer_size);
// enable seeking beyond buffer - it now is absolute position in the data stream
if (file->f_pos > file_size) {
file->f_pos = file_size;
return (-EOVERFLOW);
}
return (file->f_pos);
}
ssize_t klogger393_read (struct file * file, ///< file structure pointer
char * buf, ///< user buffer to get data
size_t count, ///< number of bytes to read
loff_t *off) ///< start/current position to read from
///< @return number of bytes placed in the buffer
{
int minor=(int)file->private_data;
off_t buffer_rp;
u32 len;
u32 not_copied;
switch (minor) {
case DEV393_MINOR(DEV393_KLOGGER):
// Increase *off if it points to already overwritten data
if (*off < (file_size - buffer_size)) {
*off = (file_size - buffer_size);
// Keep count the same?
}
// Truncate count if it exceeds remaining size in buffer
if (count > (file_size - *off))
count = file_size - *off;
#ifdef KLOGGER_BUFFER_ANY_SIZE
for (buffer_rp = *off; buffer_rp >= buffer_size; buffer_rp -= buffer_size);
#else
buffer_rp = *offt & buffer_size - 1; // buffer_size should be power of 2
#endif
len = count;
// first (usually the only) buffer copy
if (len > (buffer_size - buffer_rp))
len = (buffer_size - buffer_rp);
not_copied=copy_to_user(buf, klog393_buf + buffer_rp, len); // returns number of bytes not copied
if (not_copied) {
dev_err(g_dev_ptr,"1. tried to copy 0x%x bytes to offset 0x%llx, not copied =0x%x bytes\n", count, *off,not_copied);
return -EFAULT;
}
if (len < count) { // wrapping around the buffer
not_copied=copy_to_user(buf+len, klog393_buf, count - len); // returns number of bytes not copied
if (not_copied) {
dev_err(g_dev_ptr,"2. tried to copy 0x%x bytes to offset 0x%llx, not copied =0x%x bytes\n", count, *off,not_copied);
return -EFAULT;
}
}
*off += count;
// should we update file->f_pos=*off here too?)
return count;
break;
default:
dev_err(g_dev_ptr," Wrong minor=0x%x\n",minor);
return -EINVAL;
}
}
// SysFS interface to read/modify video memory map
#define SYSFS_PERMISSIONS 0644 /* default permissions for sysfs files */
#define SYSFS_READONLY 0444
#define SYSFS_WRITEONLY 0222
static ssize_t show_mode(struct device *dev, struct device_attribute *attr, char *buf)
{
return sprintf(buf,"0x%x\n", klog_mode);
}
static ssize_t store_mode(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
{
sscanf(buf, "%i", &klog_mode);
return count;
}
static ssize_t show_stats(struct device *dev, struct device_attribute *attr, char *buf)
{
return sprintf(buf,"Number of writes: 0x%x\n"
"Buffer size: 0x%x (%d)\n"
"Buffer write pointer: 0x%x (%d)\n"
"File size: 0x%llx (%lld)\n"
"Mode: 0x%x\n",
num_writes, buffer_size, buffer_size, buffer_wp, buffer_wp, file_size, file_size, klog_mode);
}
static DEVICE_ATTR(klogger_mode, SYSFS_PERMISSIONS, show_mode, store_mode);
static DEVICE_ATTR(klogger_stats, SYSFS_READONLY, show_stats, NULL);
static struct attribute *root_dev_attrs[] = {
&dev_attr_klogger_mode.attr,
&dev_attr_klogger_stats.attr,
NULL
};
static const struct attribute_group dev_attr_root_group = {
.attrs = root_dev_attrs,
.name = NULL,
};
static int klogger_393_sysfs_register(struct platform_device *pdev)
{
int retval=0;
struct device *dev = &pdev->dev;
if (&dev->kobj) {
if (((retval = sysfs_create_group(&dev->kobj, &dev_attr_root_group)))<0) return retval;
}
return retval;
}
int klogger_393_probe(struct platform_device *pdev)
{
int res;
struct device *dev = &pdev->dev;
const char * config_string;
struct device_node *node = pdev->dev.of_node;
const __be32 *bufsize_be;
g_dev_ptr = dev;
buffer_wp = 0;
if (node) {
#if 0
if (of_property_read_string(node, klogger393_of_prop_bufsize_name, &config_string)) {
dev_err(dev,"%s: Device tree has entry for "DEV393_NAME(DEV393_KLOGGER)", but no '%s' property is provided\n",
__func__,klogger393_of_prop_bufsize_name);
return -EINVAL;
}
if (!sscanf(config_string,"%i", &buffer_size)){
dev_err(dev,"%s: Invalid buffer size for "DEV393_NAME(DEV393_KLOGGER)".%s - %s\n",
__func__,klogger393_of_prop_bufsize_name,config_string);
return -EINVAL;
}
#endif
bufsize_be = (__be32 *)of_get_property(node, klogger393_of_prop_bufsize_name, NULL);
if (!bufsize_be) {
dev_err(dev,"%s: Device tree has entry for "DEV393_NAME(DEV393_KLOGGER)", but no '%s' property is provided\n",
__func__,klogger393_of_prop_bufsize_name);
return -EINVAL;
}
buffer_size = be32_to_cpup(bufsize_be);
//__builtin_clz
#ifndef KLOGGER_BUFFER_ANY_SIZE
buffer_size_order = 31 - __builtin_clz(buffer_size);
if (buffer_size & (( 1 << buffer_size_order) -1)){
buffer_size_order++;
buffer_size = 1 << buffer_size_order;
dev_warn(dev,"%s: Increased buffer size to %d (0x%x) to make it a power of 2 bytes\n",
__func__,buffer_size,buffer_size);
}
#endif
dev_info(dev,"%s: Setting up buffer for logging "DEV393_NAME(DEV393_KLOGGER)" of %d(0x%x) bytes\n",
__func__,buffer_size,buffer_size);
// klog393_buf = devm_kzalloc(dev, buffer_size, GFP_KERNEL);
klog393_buf = kzalloc(buffer_size, GFP_KERNEL);
if (!klog393_buf){
buffer_size = 0;
dev_err(dev,"%s: Failed to create buffer for "DEV393_NAME(DEV393_KLOGGER)" of %d(0x%x) bytes\n",
__func__,buffer_size,buffer_size);
return -ENOMEM;
}
dev_info(dev,"%s: Set up buffer for logging "DEV393_NAME(DEV393_KLOGGER)" of %d(0x%x) bytes @0x%08x\n",
__func__,buffer_size,buffer_size, (int) klog393_buf);
res = register_chrdev(DEV393_MAJOR(DEV393_KLOGGER), DEV393_NAME(DEV393_KLOGGER), &framepars_fops);
if (res < 0) {
dev_err(dev, "klogger_393_probe: couldn't get a major number %d (DEV393_MAJOR(DEV393_KLOGGER)).\n",
DEV393_MAJOR(DEV393_KLOGGER));
return res;
}
} else {
dev_warn(dev,"%s: No entry for "DEV393_NAME(DEV393_KLOGGER)", in Device Tree, logger is disabled\n", __func__);
}
res = klogger_393_sysfs_register(pdev);
dev_info(dev, DEV393_NAME(DEV393_KLOGGER)": registered sysfs, result = %d\n", res);
return 0;
}
int klogger_393_remove(struct platform_device *pdev)
{
if (klog393_buf) {
// devm_kfree(&pdev->dev, klog393_buf); // actually not needed
}
unregister_chrdev(DEV393_MAJOR(DEV393_KLOGGER), DEV393_NAME(DEV393_KLOGGER));
return 0;
}
static const struct of_device_id klogger_393_of_match[] = {
{ .compatible = "elphel,klogger-393-1.00" },
{ /* end of list */ }
};
MODULE_DEVICE_TABLE(of, klogger_393_of_match);
static struct platform_driver klogger_393 = {
.probe =klogger_393_probe,
.remove =klogger_393_remove,
.driver = {
.name = DEV393_NAME(DEV393_KLOGGER),
.of_match_table = klogger_393_of_match,
},
};
module_platform_driver(klogger_393);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Andrey Filippov <andrey@elphel.com>.");
MODULE_DESCRIPTION("Record/playback strings with FPGA timestams");