OpenWrt – Rev 4
?pathlinks?
/*
* RouterBoot helper routines
*
* Copyright (C) 2012 Gabor Juhos <juhosg@openwrt.org>
*
* 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.
*/
#define pr_fmt(fmt) "rb: " fmt
#include <linux/kernel.h>
#include <linux/kobject.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/routerboot.h>
#include <linux/rle.h>
#include <linux/lzo.h>
#include "routerboot.h"
#define RB_BLOCK_SIZE 0x1000
#define RB_ART_SIZE 0x10000
#define RB_MAGIC_ERD 0x00455244 /* extended radio data */
static struct rb_info rb_info;
static u32 get_u32(void *buf)
{
u8 *p = buf;
return ((u32) p[3] + ((u32) p[2] << 8) + ((u32) p[1] << 16) +
((u32) p[0] << 24));
}
static u16 get_u16(void *buf)
{
u8 *p = buf;
return (u16) p[1] + ((u16) p[0] << 8);
}
__init int
routerboot_find_magic(u8 *buf, unsigned int buflen, u32 *offset, bool hard)
{
u32 magic_ref = hard ? RB_MAGIC_HARD : RB_MAGIC_SOFT;
u32 magic;
u32 cur = *offset;
while (cur < buflen) {
magic = get_u32(buf + cur);
if (magic == magic_ref) {
*offset = cur;
return 0;
}
cur += 0x1000;
}
return -ENOENT;
}
__init int
routerboot_find_tag(u8 *buf, unsigned int buflen, u16 tag_id,
u8 **tag_data, u16 *tag_len)
{
uint32_t magic;
bool align = false;
int ret;
if (buflen < 4)
return -EINVAL;
magic = get_u32(buf);
switch (magic) {
case RB_MAGIC_ERD:
align = true;
/* fall trough */
case RB_MAGIC_HARD:
/* skip magic value */
buf += 4;
buflen -= 4;
break;
case RB_MAGIC_SOFT:
if (buflen < 8)
return -EINVAL;
/* skip magic and CRC value */
buf += 8;
buflen -= 8;
break;
default:
return -EINVAL;
}
ret = -ENOENT;
while (buflen > 2) {
u16 id;
u16 len;
len = get_u16(buf);
buf += 2;
buflen -= 2;
if (buflen < 2)
break;
id = get_u16(buf);
buf += 2;
buflen -= 2;
if (id == RB_ID_TERMINATOR)
break;
if (buflen < len)
break;
if (id == tag_id) {
if (tag_len)
*tag_len = len;
if (tag_data)
*tag_data = buf;
ret = 0;
break;
}
if (align)
len = (len + 3) / 4;
buf += len;
buflen -= len;
}
return ret;
}
static inline int
rb_find_hard_cfg_tag(u16 tag_id, u8 **tag_data, u16 *tag_len)
{
if (!rb_info.hard_cfg_data ||
!rb_info.hard_cfg_size)
return -ENOENT;
return routerboot_find_tag(rb_info.hard_cfg_data,
rb_info.hard_cfg_size,
tag_id, tag_data, tag_len);
}
__init const char *
rb_get_board_name(void)
{
u16 tag_len;
u8 *tag;
int err;
err = rb_find_hard_cfg_tag(RB_ID_BOARD_NAME, &tag, &tag_len);
if (err)
return NULL;
return tag;
}
__init u32
rb_get_hw_options(void)
{
u16 tag_len;
u8 *tag;
int err;
err = rb_find_hard_cfg_tag(RB_ID_HW_OPTIONS, &tag, &tag_len);
if (err)
return 0;
return get_u32(tag);
}
static void * __init
__rb_get_wlan_data(u16 id)
{
u16 tag_len;
u8 *tag;
void *buf;
int err;
u32 magic;
size_t src_done;
size_t dst_done;
err = rb_find_hard_cfg_tag(RB_ID_WLAN_DATA, &tag, &tag_len);
if (err) {
pr_err("no calibration data found\n");
goto err;
}
buf = kmalloc(RB_ART_SIZE, GFP_KERNEL);
if (buf == NULL) {
pr_err("no memory for calibration data\n");
goto err;
}
magic = get_u32(tag);
if (magic == RB_MAGIC_ERD) {
u8 *erd_data;
u16 erd_len;
if (id == 0)
goto err_free;
err = routerboot_find_tag(tag, tag_len, id,
&erd_data, &erd_len);
if (err) {
pr_err("no ERD data found for id %u\n", id);
goto err_free;
}
dst_done = RB_ART_SIZE;
err = lzo1x_decompress_safe(erd_data, erd_len, buf, &dst_done);
if (err) {
pr_err("unable to decompress calibration data %d\n",
err);
goto err_free;
}
} else {
if (id != 0)
goto err_free;
err = rle_decode((char *) tag, tag_len, buf, RB_ART_SIZE,
&src_done, &dst_done);
if (err) {
pr_err("unable to decode calibration data\n");
goto err_free;
}
}
return buf;
err_free:
kfree(buf);
err:
return NULL;
}
__init void *
rb_get_wlan_data(void)
{
return __rb_get_wlan_data(0);
}
__init void *
rb_get_ext_wlan_data(u16 id)
{
return __rb_get_wlan_data(id);
}
__init const struct rb_info *
rb_init_info(void *data, unsigned int size)
{
unsigned int offset;
if (size == 0 || (size % RB_BLOCK_SIZE) != 0)
return NULL;
for (offset = 0; offset < size; offset += RB_BLOCK_SIZE) {
u32 magic;
magic = get_u32(data + offset);
switch (magic) {
case RB_MAGIC_HARD:
rb_info.hard_cfg_offs = offset;
break;
case RB_MAGIC_SOFT:
rb_info.soft_cfg_offs = offset;
break;
}
}
if (!rb_info.hard_cfg_offs) {
pr_err("could not find a valid RouterBOOT hard config\n");
return NULL;
}
if (!rb_info.soft_cfg_offs) {
pr_err("could not find a valid RouterBOOT soft config\n");
return NULL;
}
rb_info.hard_cfg_size = RB_BLOCK_SIZE;
rb_info.hard_cfg_data = kmemdup(data + rb_info.hard_cfg_offs,
RB_BLOCK_SIZE, GFP_KERNEL);
if (!rb_info.hard_cfg_data)
return NULL;
rb_info.board_name = rb_get_board_name();
rb_info.hw_options = rb_get_hw_options();
return &rb_info;
}
static char *rb_ext_wlan_data;
static ssize_t
rb_ext_wlan_data_read(struct file *filp, struct kobject *kobj,
struct bin_attribute *attr, char *buf,
loff_t off, size_t count)
{
if (off + count > attr->size)
return -EFBIG;
memcpy(buf, &rb_ext_wlan_data[off], count);
return count;
}
static const struct bin_attribute rb_ext_wlan_data_attr = {
.attr = {
.name = "ext_wlan_data",
.mode = S_IRUSR | S_IWUSR,
},
.read = rb_ext_wlan_data_read,
.size = RB_ART_SIZE,
};
static int __init rb_sysfs_init(void)
{
struct kobject *rb_kobj;
int ret;
rb_ext_wlan_data = rb_get_ext_wlan_data(1);
if (rb_ext_wlan_data == NULL)
return -ENOENT;
rb_kobj = kobject_create_and_add("routerboot", firmware_kobj);
if (rb_kobj == NULL) {
ret = -ENOMEM;
pr_err("unable to create sysfs entry\n");
goto err_free_wlan_data;
}
ret = sysfs_create_bin_file(rb_kobj, &rb_ext_wlan_data_attr);
if (ret) {
pr_err("unable to create sysfs file, %d\n", ret);
goto err_put_kobj;
}
return 0;
err_put_kobj:
kobject_put(rb_kobj);
err_free_wlan_data:
kfree(rb_ext_wlan_data);
return ret;
}
late_initcall(rb_sysfs_init);