target/linux/brcm47xx/patches-4.14/820-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 @@ -1,2 +1,2 @@
   9 -obj-$(CONFIG_BCM47XX_NVRAM)            += bcm47xx_nvram.o
  10 +obj-$(CONFIG_BCM47XX_NVRAM)            += bcm47xx_nvram.o cfe_env.o
  11  obj-$(CONFIG_BCM47XX_SPROM)            += bcm47xx_sprom.o
  12 --- /dev/null
  13 +++ b/drivers/firmware/broadcom/cfe_env.c
  14 @@ -0,0 +1,228 @@
  15 +/*
  16 + * CFE environment variable access
  17 + *
  18 + * Copyright 2001-2003, Broadcom Corporation
  19 + * Copyright 2006, Felix Fietkau <nbd@nbd.name>
  20 + *
  21 + * This program is free software; you can redistribute  it and/or modify it
  22 + * under  the terms of  the GNU General  Public License as published by the
  23 + * Free Software Foundation;  either version 2 of the  License, or (at your
  24 + * option) any later version.
  25 + */
  26 +
  27 +#include <linux/init.h>
  28 +#include <linux/module.h>
  29 +#include <linux/kernel.h>
  30 +#include <linux/string.h>
  31 +#include <asm/io.h>
  32 +#include <linux/uaccess.h>
  33 +
  34 +#define NVRAM_SIZE       (0x1ff0)
  35 +static char _nvdata[NVRAM_SIZE];
  36 +static char _valuestr[256];
  37 +
  38 +/*
  39 + * TLV types.  These codes are used in the "type-length-value"
  40 + * encoding of the items stored in the NVRAM device (flash or EEPROM)
  41 + *
  42 + * The layout of the flash/nvram is as follows:
  43 + *
  44 + * <type> <length> <data ...> <type> <length> <data ...> <type_end>
  45 + *
  46 + * The type code of "ENV_TLV_TYPE_END" marks the end of the list.
  47 + * The "length" field marks the length of the data section, not
  48 + * including the type and length fields.
  49 + *
  50 + * Environment variables are stored as follows:
  51 + *
  52 + * <type_env> <length> <flags> <name> = <value>
  53 + *
  54 + * If bit 0 (low bit) is set, the length is an 8-bit value.
  55 + * If bit 0 (low bit) is clear, the length is a 16-bit value
  56 + *
  57 + * Bit 7 set indicates "user" TLVs.  In this case, bit 0 still
  58 + * indicates the size of the length field.
  59 + *
  60 + * Flags are from the constants below:
  61 + *
  62 + */
  63 +#define ENV_LENGTH_16BITS      0x00    /* for low bit */
  64 +#define ENV_LENGTH_8BITS       0x01
  65 +
  66 +#define ENV_TYPE_USER          0x80
  67 +
  68 +#define ENV_CODE_SYS(n,l) (((n)<<1)|(l))
  69 +#define ENV_CODE_USER(n,l) ((((n)<<1)|(l)) | ENV_TYPE_USER)
  70 +
  71 +/*
  72 + * The actual TLV types we support
  73 + */
  74 +
  75 +#define ENV_TLV_TYPE_END       0x00
  76 +#define ENV_TLV_TYPE_ENV       ENV_CODE_SYS(0,ENV_LENGTH_8BITS)
  77 +
  78 +/*
  79 + * Environment variable flags
  80 + */
  81 +
  82 +#define ENV_FLG_NORMAL         0x00    /* normal read/write */
  83 +#define ENV_FLG_BUILTIN                0x01    /* builtin - not stored in flash */
  84 +#define ENV_FLG_READONLY       0x02    /* read-only - cannot be changed */
  85 +
  86 +#define ENV_FLG_MASK           0xFF    /* mask of attributes we keep */
  87 +#define ENV_FLG_ADMIN          0x100   /* lets us internally override permissions */
  88 +
  89 +
  90 +/*  *********************************************************************
  91 +    *  _nvram_read(buffer,offset,length)
  92 +    *
  93 +    *  Read data from the NVRAM device
  94 +    *
  95 +    *  Input parameters:
  96 +    *             buffer - destination buffer
  97 +    *             offset - offset of data to read
  98 +    *             length - number of bytes to read
  99 +    *
 100 +    *  Return value:
 101 +    *             number of bytes read, or <0 if error occured
 102 +    ********************************************************************* */
 103 +static int
 104 +_nvram_read(unsigned char *nv_buf, unsigned char *buffer, int offset, int length)
 105 +{
 106 +    int i;
 107 +    if (offset > NVRAM_SIZE)
 108 +       return -1;
 109 +
 110 +    for ( i = 0; i < length; i++) {
 111 +       buffer[i] = ((volatile unsigned char*)nv_buf)[offset + i];
 112 +    }
 113 +    return length;
 114 +}
 115 +
 116 +
 117 +static char*
 118 +_strnchr(const char *dest,int c,size_t cnt)
 119 +{
 120 +       while (*dest && (cnt > 0)) {
 121 +       if (*dest == c) return (char *) dest;
 122 +       dest++;
 123 +       cnt--;
 124 +       }
 125 +       return NULL;
 126 +}
 127 +
 128 +
 129 +
 130 +/*
 131 + * Core support API: Externally visible.
 132 + */
 133 +
 134 +/*
 135 + * Get the value of an NVRAM variable
 136 + * @param      name    name of variable to get
 137 + * @return     value of variable or NULL if undefined
 138 + */
 139 +
 140 +char *cfe_env_get(unsigned char *nv_buf, const char *name)
 141 +{
 142 +    int size;
 143 +    unsigned char *buffer;
 144 +    unsigned char *ptr;
 145 +    unsigned char *envval;
 146 +    unsigned int reclen;
 147 +    unsigned int rectype;
 148 +    int offset;
 149 +    int flg;
 150 +
 151 +       if (!strcmp(name, "nvram_type"))
 152 +               return "cfe";
 153 +
 154 +    size = NVRAM_SIZE;
 155 +    buffer = &_nvdata[0];
 156 +
 157 +    ptr = buffer;
 158 +    offset = 0;
 159 +
 160 +    /* Read the record type and length */
 161 +    if (_nvram_read(nv_buf, ptr,offset,1) != 1) {
 162 +       goto error;
 163 +    }
 164 +
 165 +    while ((*ptr != ENV_TLV_TYPE_END)  && (size > 1)) {
 166 +
 167 +       /* Adjust pointer for TLV type */
 168 +       rectype = *(ptr);
 169 +       offset++;
 170 +       size--;
 171 +
 172 +       /*
 173 +        * Read the length.  It can be either 1 or 2 bytes
 174 +        * depending on the code
 175 +        */
 176 +       if (rectype & ENV_LENGTH_8BITS) {
 177 +           /* Read the record type and length - 8 bits */
 178 +           if (_nvram_read(nv_buf, ptr,offset,1) != 1) {
 179 +               goto error;
 180 +           }
 181 +           reclen = *(ptr);
 182 +           size--;
 183 +           offset++;
 184 +       }
 185 +       else {
 186 +           /* Read the record type and length - 16 bits, MSB first */
 187 +           if (_nvram_read(nv_buf, ptr,offset,2) != 2) {
 188 +               goto error;
 189 +           }
 190 +           reclen = (((unsigned int) *(ptr)) << 8) + (unsigned int) *(ptr+1);
 191 +           size -= 2;
 192 +           offset += 2;
 193 +       }
 194 +
 195 +       if (reclen > size)
 196 +           break;      /* should not happen, bad NVRAM */
 197 +
 198 +       switch (rectype) {
 199 +           case ENV_TLV_TYPE_ENV:
 200 +               /* Read the TLV data */
 201 +               if (_nvram_read(nv_buf, ptr,offset,reclen) != reclen)
 202 +                   goto error;
 203 +               flg = *ptr++;
 204 +               envval = (unsigned char *) _strnchr(ptr,'=',(reclen-1));
 205 +               if (envval) {
 206 +                   *envval++ = '\0';
 207 +                   memcpy(_valuestr,envval,(reclen-1)-(envval-ptr));
 208 +                   _valuestr[(reclen-1)-(envval-ptr)] = '\0';
 209 +#if 0
 210 +                   printk(KERN_INFO "NVRAM:%s=%s\n", ptr, _valuestr);
 211 +#endif
 212 +                   if(!strcmp(ptr, name)){
 213 +                       return _valuestr;
 214 +                   }
 215 +                   if((strlen(ptr) > 1) && !strcmp(&ptr[1], name))
 216 +                       return _valuestr;
 217 +               }
 218 +               break;
 219 +
 220 +           default:
 221 +               /* Unknown TLV type, skip it. */
 222 +               break;
 223 +           }
 224 +
 225 +       /*
 226 +        * Advance to next TLV
 227 +        */
 228 +
 229 +       size -= (int)reclen;
 230 +       offset += reclen;
 231 +
 232 +       /* Read the next record type */
 233 +       ptr = buffer;
 234 +       if (_nvram_read(nv_buf, ptr,offset,1) != 1)
 235 +           goto error;
 236 +       }
 237 +
 238 +error:
 239 +    return NULL;
 240 +
 241 +}
 242 +
 243 --- a/drivers/firmware/broadcom/bcm47xx_nvram.c
 244 +++ b/drivers/firmware/broadcom/bcm47xx_nvram.c
 245 @@ -37,6 +37,8 @@ struct nvram_header {
 246  static char nvram_buf[NVRAM_SPACE];
 247  static size_t nvram_len;
 248  static const u32 nvram_sizes[] = {0x6000, 0x8000, 0xF000, 0x10000};
 249 +static int cfe_env;
 250 +extern char *cfe_env_get(char *nv_buf, const char *name);
 251
 252  static u32 find_nvram_size(void __iomem *end)
 253  {
 254 @@ -56,7 +58,9 @@ static u32 find_nvram_size(void __iomem
 255  static int nvram_find_and_copy(void __iomem *iobase, u32 lim)
 256  {
 257         struct nvram_header __iomem *header;
 258 +       int i;
 259         u32 off;
 260 +       u32 *src, *dst;
 261         u32 size;
 262
 263         if (nvram_len) {
 264 @@ -64,6 +68,26 @@ static int nvram_find_and_copy(void __io
 265                 return -EEXIST;
 266         }
 267
 268 +       cfe_env = 0;
 269 +
 270 +       /* XXX: hack for supporting the CFE environment stuff on WGT634U */
 271 +       if (lim >= 8 * 1024 * 1024) {
 272 +               src = (u32 *)(iobase + 8 * 1024 * 1024 - 0x2000);
 273 +               dst = (u32 *)nvram_buf;
 274 +
 275 +               if ((*src & 0xff00ff) == 0x000001) {
 276 +                       printk("early_nvram_init: WGT634U NVRAM found.\n");
 277 +
 278 +                       for (i = 0; i < 0x1ff0; i++) {
 279 +                               if (*src == 0xFFFFFFFF)
 280 +                                       break;
 281 +                               *dst++ = *src++;
 282 +                       }
 283 +                       cfe_env = 1;
 284 +                       return 0;
 285 +               }
 286 +       }
 287 +
 288         /* TODO: when nvram is on nand flash check for bad blocks first. */
 289         off = FLASH_MIN;
 290         while (off <= lim) {
 291 @@ -174,6 +198,13 @@ int bcm47xx_nvram_getenv(const char *nam
 292         if (!name)
 293                 return -EINVAL;
 294
 295 +       if (cfe_env) {
 296 +               value = cfe_env_get(nvram_buf, name);
 297 +               if (!value)
 298 +                       return -ENOENT;
 299 +               return snprintf(val, val_len, "%s", value);
 300 +       }
 301 +
 302         if (!nvram_len) {
 303                 err = nvram_init();
 304                 if (err)