target/linux/brcm47xx/patches-4.4/820-wgt634u-nvram-fix.patch

   1 The Netgear wgt634u uses a different format for storing the
   2 configuration. This patch is needed to read out the correct
   3 configuration. The cfe_env.c file uses a different method way to read
   4 out the configuration than the in kernel cfe config reader.
   5
   6 --- a/drivers/firmware/broadcom/Makefile
   7 +++ b/drivers/firmware/broadcom/Makefile
   8 @@ -1 +1 @@
   9 -obj-$(CONFIG_BCM47XX_NVRAM)            += bcm47xx_nvram.o
  10 +obj-$(CONFIG_BCM47XX_NVRAM)            += bcm47xx_nvram.o cfe_env.o
  11 --- /dev/null
  12 +++ b/drivers/firmware/broadcom/cfe_env.c
  13 @@ -0,0 +1,228 @@
  14 +/*
  15 + * CFE environment variable access
  16 + *
  17 + * Copyright 2001-2003, Broadcom Corporation
  18 + * Copyright 2006, Felix Fietkau <nbd@openwrt.org>
  19 + *
  20 + * This program is free software; you can redistribute  it and/or modify it
  21 + * under  the terms of  the GNU General  Public License as published by the
  22 + * Free Software Foundation;  either version 2 of the  License, or (at your
  23 + * option) any later version.
  24 + */
  25 +
  26 +#include <linux/init.h>
  27 +#include <linux/module.h>
  28 +#include <linux/kernel.h>
  29 +#include <linux/string.h>
  30 +#include <asm/io.h>
  31 +#include <asm/uaccess.h>
  32 +
  33 +#define NVRAM_SIZE       (0x1ff0)
  34 +static char _nvdata[NVRAM_SIZE];
  35 +static char _valuestr[256];
  36 +
  37 +/*
  38 + * TLV types.  These codes are used in the "type-length-value"
  39 + * encoding of the items stored in the NVRAM device (flash or EEPROM)
  40 + *
  41 + * The layout of the flash/nvram is as follows:
  42 + *
  43 + * <type> <length> <data ...> <type> <length> <data ...> <type_end>
  44 + *
  45 + * The type code of "ENV_TLV_TYPE_END" marks the end of the list.
  46 + * The "length" field marks the length of the data section, not
  47 + * including the type and length fields.
  48 + *
  49 + * Environment variables are stored as follows:
  50 + *
  51 + * <type_env> <length> <flags> <name> = <value>
  52 + *
  53 + * If bit 0 (low bit) is set, the length is an 8-bit value.
  54 + * If bit 0 (low bit) is clear, the length is a 16-bit value
  55 + *
  56 + * Bit 7 set indicates "user" TLVs.  In this case, bit 0 still
  57 + * indicates the size of the length field.
  58 + *
  59 + * Flags are from the constants below:
  60 + *
  61 + */
  62 +#define ENV_LENGTH_16BITS      0x00    /* for low bit */
  63 +#define ENV_LENGTH_8BITS       0x01
  64 +
  65 +#define ENV_TYPE_USER          0x80
  66 +
  67 +#define ENV_CODE_SYS(n,l) (((n)<<1)|(l))
  68 +#define ENV_CODE_USER(n,l) ((((n)<<1)|(l)) | ENV_TYPE_USER)
  69 +
  70 +/*
  71 + * The actual TLV types we support
  72 + */
  73 +
  74 +#define ENV_TLV_TYPE_END       0x00
  75 +#define ENV_TLV_TYPE_ENV       ENV_CODE_SYS(0,ENV_LENGTH_8BITS)
  76 +
  77 +/*
  78 + * Environment variable flags
  79 + */
  80 +
  81 +#define ENV_FLG_NORMAL         0x00    /* normal read/write */
  82 +#define ENV_FLG_BUILTIN                0x01    /* builtin - not stored in flash */
  83 +#define ENV_FLG_READONLY       0x02    /* read-only - cannot be changed */
  84 +
  85 +#define ENV_FLG_MASK           0xFF    /* mask of attributes we keep */
  86 +#define ENV_FLG_ADMIN          0x100   /* lets us internally override permissions */
  87 +
  88 +
  89 +/*  *********************************************************************
  90 +    *  _nvram_read(buffer,offset,length)
  91 +    *
  92 +    *  Read data from the NVRAM device
  93 +    *
  94 +    *  Input parameters:
  95 +    *             buffer - destination buffer
  96 +    *             offset - offset of data to read
  97 +    *             length - number of bytes to read
  98 +    *
  99 +    *  Return value:
 100 +    *             number of bytes read, or <0 if error occured
 101 +    ********************************************************************* */
 102 +static int
 103 +_nvram_read(unsigned char *nv_buf, unsigned char *buffer, int offset, int length)
 104 +{
 105 +    int i;
 106 +    if (offset > NVRAM_SIZE)
 107 +       return -1;
 108 +
 109 +    for ( i = 0; i < length; i++) {
 110 +       buffer[i] = ((volatile unsigned char*)nv_buf)[offset + i];
 111 +    }
 112 +    return length;
 113 +}
 114 +
 115 +
 116 +static char*
 117 +_strnchr(const char *dest,int c,size_t cnt)
 118 +{
 119 +       while (*dest && (cnt > 0)) {
 120 +       if (*dest == c) return (char *) dest;
 121 +       dest++;
 122 +       cnt--;
 123 +       }
 124 +       return NULL;
 125 +}
 126 +
 127 +
 128 +
 129 +/*
 130 + * Core support API: Externally visible.
 131 + */
 132 +
 133 +/*
 134 + * Get the value of an NVRAM variable
 135 + * @param      name    name of variable to get
 136 + * @return     value of variable or NULL if undefined
 137 + */
 138 +
 139 +char *cfe_env_get(unsigned char *nv_buf, const char *name)
 140 +{
 141 +    int size;
 142 +    unsigned char *buffer;
 143 +    unsigned char *ptr;
 144 +    unsigned char *envval;
 145 +    unsigned int reclen;
 146 +    unsigned int rectype;
 147 +    int offset;
 148 +    int flg;
 149 +
 150 +       if (!strcmp(name, "nvram_type"))
 151 +               return "cfe";
 152 +
 153 +    size = NVRAM_SIZE;
 154 +    buffer = &_nvdata[0];
 155 +
 156 +    ptr = buffer;
 157 +    offset = 0;
 158 +
 159 +    /* Read the record type and length */
 160 +    if (_nvram_read(nv_buf, ptr,offset,1) != 1) {
 161 +       goto error;
 162 +    }
 163 +
 164 +    while ((*ptr != ENV_TLV_TYPE_END)  && (size > 1)) {
 165 +
 166 +       /* Adjust pointer for TLV type */
 167 +       rectype = *(ptr);
 168 +       offset++;
 169 +       size--;
 170 +
 171 +       /*
 172 +        * Read the length.  It can be either 1 or 2 bytes
 173 +        * depending on the code
 174 +        */
 175 +       if (rectype & ENV_LENGTH_8BITS) {
 176 +           /* Read the record type and length - 8 bits */
 177 +           if (_nvram_read(nv_buf, ptr,offset,1) != 1) {
 178 +               goto error;
 179 +           }
 180 +           reclen = *(ptr);
 181 +           size--;
 182 +           offset++;
 183 +       }
 184 +       else {
 185 +           /* Read the record type and length - 16 bits, MSB first */
 186 +           if (_nvram_read(nv_buf, ptr,offset,2) != 2) {
 187 +               goto error;
 188 +           }
 189 +           reclen = (((unsigned int) *(ptr)) << 8) + (unsigned int) *(ptr+1);
 190 +           size -= 2;
 191 +           offset += 2;
 192 +       }
 193 +
 194 +       if (reclen > size)
 195 +           break;      /* should not happen, bad NVRAM */
 196 +
 197 +       switch (rectype) {
 198 +           case ENV_TLV_TYPE_ENV:
 199 +               /* Read the TLV data */
 200 +               if (_nvram_read(nv_buf, ptr,offset,reclen) != reclen)
 201 +                   goto error;
 202 +               flg = *ptr++;
 203 +               envval = (unsigned char *) _strnchr(ptr,'=',(reclen-1));
 204 +               if (envval) {
 205 +                   *envval++ = '\0';
 206 +                   memcpy(_valuestr,envval,(reclen-1)-(envval-ptr));
 207 +                   _valuestr[(reclen-1)-(envval-ptr)] = '\0';
 208 +#if 0
 209 +                   printk(KERN_INFO "NVRAM:%s=%s\n", ptr, _valuestr);
 210 +#endif
 211 +                   if(!strcmp(ptr, name)){
 212 +                       return _valuestr;
 213 +                   }
 214 +                   if((strlen(ptr) > 1) && !strcmp(&ptr[1], name))
 215 +                       return _valuestr;
 216 +               }
 217 +               break;
 218 +
 219 +           default:
 220 +               /* Unknown TLV type, skip it. */
 221 +               break;
 222 +           }
 223 +
 224 +       /*
 225 +        * Advance to next TLV
 226 +        */
 227 +
 228 +       size -= (int)reclen;
 229 +       offset += reclen;
 230 +
 231 +       /* Read the next record type */
 232 +       ptr = buffer;
 233 +       if (_nvram_read(nv_buf, ptr,offset,1) != 1)
 234 +           goto error;
 235 +       }
 236 +
 237 +error:
 238 +    return NULL;
 239 +
 240 +}
 241 +
 242 --- a/drivers/firmware/broadcom/bcm47xx_nvram.c
 243 +++ b/drivers/firmware/broadcom/bcm47xx_nvram.c
 244 @@ -37,6 +37,8 @@ struct nvram_header {
 245  static char nvram_buf[NVRAM_SPACE];
 246  static size_t nvram_len;
 247  static const u32 nvram_sizes[] = {0x8000, 0xF000, 0x10000};
 248 +static int cfe_env;
 249 +extern char *cfe_env_get(char *nv_buf, const char *name);
 250
 251  static u32 find_nvram_size(void __iomem *end)
 252  {
 253 @@ -66,6 +68,26 @@ static int nvram_find_and_copy(void __io
 254                 return -EEXIST;
 255         }
 256
 257 +       cfe_env = 0;
 258 +
 259 +       /* XXX: hack for supporting the CFE environment stuff on WGT634U */
 260 +       if (lim >= 8 * 1024 * 1024) {
 261 +               src = (u32 *)(iobase + 8 * 1024 * 1024 - 0x2000);
 262 +               dst = (u32 *)nvram_buf;
 263 +
 264 +               if ((*src & 0xff00ff) == 0x000001) {
 265 +                       printk("early_nvram_init: WGT634U NVRAM found.\n");
 266 +
 267 +                       for (i = 0; i < 0x1ff0; i++) {
 268 +                               if (*src == 0xFFFFFFFF)
 269 +                                       break;
 270 +                               *dst++ = *src++;
 271 +                       }
 272 +                       cfe_env = 1;
 273 +                       return 0;
 274 +               }
 275 +       }
 276 +
 277         /* TODO: when nvram is on nand flash check for bad blocks first. */
 278         off = FLASH_MIN;
 279         while (off <= lim) {
 280 @@ -180,6 +202,13 @@ int bcm47xx_nvram_getenv(const char *nam
 281         if (!name)
 282                 return -EINVAL;
 283
 284 +       if (cfe_env) {
 285 +               value = cfe_env_get(nvram_buf, name);
 286 +               if (!value)
 287 +                       return -ENOENT;
 288 +               return snprintf(val, val_len, "%s", value);
 289 +       }
 290 +
 291         if (!nvram_len) {
 292                 err = nvram_init();
 293                 if (err)