uboot for s3c2410 nandboot 使用saveenv保存环境变量

1、因为定义了CFG_NAND_LEGACY，因此主要修改saveenv中对nand的读写函数为nand_legacy的读写函数，修改common/env_nand.c如下：
#include <common.h>

#if defined(CFG_ENV_IS_IN_NAND) /* Environment is in Nand Flash */

#include <command.h>
#include <environment.h>
#include <linux/stddef.h>
#include <malloc.h>
#include <nand.h>

#if ((CONFIG_COMMANDS&(CFG_CMD_ENV|CFG_CMD_NAND)) == (CFG_CMD_ENV|CFG_CMD_NAND))
#define CMD_SAVEENV
#elif defined(CFG_ENV_OFFSET_REDUND)
#error Cannot use CFG_ENV_OFFSET_REDUND without CFG_CMD_ENV & CFG_CMD_NAND
#endif

#if defined(CFG_ENV_SIZE_REDUND) && (CFG_ENV_SIZE_REDUND != CFG_ENV_SIZE)
#error CFG_ENV_SIZE_REDUND should be the same as CFG_ENV_SIZE
#endif

#ifdef CONFIG_INFERNO
#error CONFIG_INFERNO not supported yet
#endif

/* My Add*/
int nand_legacy_erase(struct nand_chip* nand,
size_t ofs, size_t len, int clean);

int nand_legacy_rw (struct nand_chip* nand, int cmd,
size_t start, size_t len,
size_t * retlen, u_char * buf);

/* My Add*/
extern struct nand_chip nand_dev_desc[CFG_MAX_NAND_DEVICE];

/* info for NAND chips, defined in drivers/nand/nand.c */
//extern nand_info_t nand_info[];
nand_info_t nand_info[CFG_MAX_NAND_DEVICE];

/* references to names in env_common.c */
extern uchar default_environment[];
extern int default_environment_size;

char * env_name_spec = "NAND";

#ifdef ENV_IS_EMBEDDED
extern uchar environment[];
env_t *env_ptr = (env_t *)(&environment[0]);
#else /* ! ENV_IS_EMBEDDED */
env_t *env_ptr = 0;
#endif /* ENV_IS_EMBEDDED */

/* local functions */
#if !defined(ENV_IS_EMBEDDED)
static void use_default(void);
#endif

DECLARE_GLOBAL_DATA_PTR;

uchar env_get_char_spec (int index)
{
return ( *((uchar *)(gd->env_addr + index)) );
}

/* this is called before nand_init()
* so we can't read Nand to validate env data.
* Mark it OK for now. env_relocate() in env_common.c
* will call our relocate function which will does
* the real validation.
*
* When using a NAND boot image (like sequoia_nand), the environment
* can be embedded or attached to the U-Boot image in NAND flash. This way
* the SPL loads not only the U-Boot image from NAND but also the
* environment.
*/
int env_init(void)
{
#if defined(ENV_IS_EMBEDDED)
ulong total;
int crc1_ok = 0, crc2_ok = 0;
env_t *tmp_env1, *tmp_env2;

total = CFG_ENV_SIZE;

tmp_env1 = env_ptr;
tmp_env2 = (env_t *)((ulong)env_ptr + CFG_ENV_SIZE);

crc1_ok = (crc32(0, tmp_env1->data, ENV_SIZE) == tmp_env1->crc);
crc2_ok = (crc32(0, tmp_env2->data, ENV_SIZE) == tmp_env2->crc);

if (!crc1_ok && !crc2_ok)
gd->env_valid = 0;
else if(crc1_ok && !crc2_ok)
gd->env_valid = 1;
else if(!crc1_ok && crc2_ok)
gd->env_valid = 2;
else {
/* both ok - check serial */
if(tmp_env1->flags == 255 && tmp_env2->flags == 0)
gd->env_valid = 2;
else if(tmp_env2->flags == 255 && tmp_env1->flags == 0)
gd->env_valid = 1;
else if(tmp_env1->flags > tmp_env2->flags)
gd->env_valid = 1;
else if(tmp_env2->flags > tmp_env1->flags)
gd->env_valid = 2;
else /* flags are equal - almost impossible */
gd->env_valid = 1;
}

if (gd->env_valid == 1)
env_ptr = tmp_env1;
else if (gd->env_valid == 2)
env_ptr = tmp_env2;
#else /* ENV_IS_EMBEDDED */
gd->env_addr = (ulong)&default_environment[0];
gd->env_valid = 1;
#endif /* ENV_IS_EMBEDDED */

return (0);
}

#ifdef CMD_SAVEENV
/*
* The legacy NAND code saved the environment in the first NAND device i.e.,
* nand_dev_desc + 0. This is also the behaviour using the new NAND code.
*/
#ifdef CFG_ENV_OFFSET_REDUND
int saveenv(void)
{
ulong total;
int ret = 0;

env_ptr->flags++;
total = CFG_ENV_SIZE;

if(gd->env_valid == 1) {
puts ("Erasing redundant Nand...");
if (nand_erase(&nand_info[0],
CFG_ENV_OFFSET_REDUND, CFG_ENV_SIZE))
return 1;
puts ("Writing to redundant Nand... ");
ret = nand_write(&nand_info[0], CFG_ENV_OFFSET_REDUND, &total,
(u_char*) env_ptr);
} else {
puts ("Erasing Nand...");
if (nand_erase(&nand_info[0],
CFG_ENV_OFFSET, CFG_ENV_SIZE))
return 1;

puts ("Writing to Nand... ");
ret = nand_write(&nand_info[0], CFG_ENV_OFFSET, &total,
(u_char*) env_ptr);
}
if (ret || total != CFG_ENV_SIZE)
return 1;

puts ("done/n");
gd->env_valid = (gd->env_valid == 2 ? 1 : 2);
return ret;
}
#else /* ! CFG_ENV_OFFSET_REDUND */
int saveenv(void)
{
ulong total;
int ret = 0;

puts ("Erasing Nand...");
//if (nand_erase(&nand_info[0], CFG_ENV_OFFSET, CFG_ENV_SIZE))
if (nand_legacy_erase(nand_dev_desc+0, CFG_ENV_OFFSET, CFG_ENV_SIZE, 0))
return 1;

puts ("Writing to Nand... ");
total = CFG_ENV_SIZE;
//ret = nand_write(&nand_info[0], CFG_ENV_OFFSET, &total, (u_char*)env_ptr);
nand_legacy_rw(nand_dev_desc+0, 0x00 | 0x02, CFG_ENV_OFFSET, CFG_ENV_SIZE, &total, (u_char*)env_ptr);
if (ret || total != CFG_ENV_SIZE)
return 1;

puts ("done/n");
return ret;
}
#endif /* CFG_ENV_OFFSET_REDUND */
#endif /* CMD_SAVEENV */

#ifdef CFG_ENV_OFFSET_REDUND
void env_relocate_spec (void)
{
#if !defined(ENV_IS_EMBEDDED)
ulong total;
int crc1_ok = 0, crc2_ok = 0;
env_t *tmp_env1, *tmp_env2;

total = CFG_ENV_SIZE;

tmp_env1 = (env_t *) malloc(CFG_ENV_SIZE);
tmp_env2 = (env_t *) malloc(CFG_ENV_SIZE);

nand_read(&nand_info[0], CFG_ENV_OFFSET, &total,
(u_char*) tmp_env1);
nand_read(&nand_info[0], CFG_ENV_OFFSET_REDUND, &total,
(u_char*) tmp_env2);

crc1_ok = (crc32(0, tmp_env1->data, ENV_SIZE) == tmp_env1->crc);
crc2_ok = (crc32(0, tmp_env2->data, ENV_SIZE) == tmp_env2->crc);

if(!crc1_ok && !crc2_ok)
return use_default();
else if(crc1_ok && !crc2_ok)
gd->env_valid = 1;
else if(!crc1_ok && crc2_ok)
gd->env_valid = 2;
else {
/* both ok - check serial */
if(tmp_env1->flags == 255 && tmp_env2->flags == 0)
gd->env_valid = 2;
else if(tmp_env2->flags == 255 && tmp_env1->flags == 0)
gd->env_valid = 1;
else if(tmp_env1->flags > tmp_env2->flags)
gd->env_valid = 1;
else if(tmp_env2->flags > tmp_env1->flags)
gd->env_valid = 2;
else /* flags are equal - almost impossible */
gd->env_valid = 1;

}

free(env_ptr);
if(gd->env_valid == 1) {
env_ptr = tmp_env1;
free(tmp_env2);
} else {
env_ptr = tmp_env2;
free(tmp_env1);
}

#endif /* ! ENV_IS_EMBEDDED */
}
#else /* ! CFG_ENV_OFFSET_REDUND */
/*
* The legacy NAND code saved the environment in the first NAND device i.e.,
* nand_dev_desc + 0. This is also the behaviour using the new NAND code.
*/
void env_relocate_spec (void)
{
#if !defined(ENV_IS_EMBEDDED)
ulong total;
int ret;

total = CFG_ENV_SIZE;
//ret = nand_read(&nand_info[0], CFG_ENV_OFFSET, &total, (u_char*)env_ptr);
ret=nand_legacy_rw(nand_dev_desc+0, 0x01 | 0x02, CFG_ENV_OFFSET, CFG_ENV_SIZE, &total, (u_char*)env_ptr);
if (ret || total != CFG_ENV_SIZE)
return use_default();

if (crc32(0, env_ptr->data, ENV_SIZE) != env_ptr->crc)
return use_default();
#endif /* ! ENV_IS_EMBEDDED */
}
#endif /* CFG_ENV_OFFSET_REDUND */

#if !defined(ENV_IS_EMBEDDED)
static void use_default()
{
puts ("*** Warning - bad CRC or NAND, using default environment/n/n");

if (default_environment_size > CFG_ENV_SIZE){
puts ("*** Error - default environment is too large/n/n");
return;
}

memset (env_ptr, 0, sizeof(env_t));
memcpy (env_ptr->data,
default_environment,
default_environment_size);
env_ptr->crc = crc32(0, env_ptr->data, ENV_SIZE);
gd->env_valid = 1;

}
#endif

#endif /* CFG_ENV_IS_IN_NAND */

2、修改include/configs/zj2410.h：
/*-----------------------------------------------------------------------
* NAND FLASH BOOT
*/
#define CONFIG_S3C2410_NAND_BOOT 1
#define STACK_BASE 0x33f00000
#define STACK_SIZE 0x8000
#define UBOOT_RAM_BASE 0x30100000

#define NAND_CTL_BASE 0x4e000000
#define bINT_CTL(Nb) _REG(INT_CTL_BASE+(Nb))

#define oNFCONF 0x00
#define oNFCMD 0x04
#define oNFADDR 0x08
#define oNFDATA 0x0c
#define oNFSTAT 0x10
#define oNFECC 0x14

/*-----------------------------------------------------------------------
* NAND flash settings
*/
#define CFG_ENV_IS_IN_NAND 1
#define CFG_ENV_SIZE 0x10000 /* Total Size of Environment Sector */
#define CFG_ENV_OFFSET 0x20000 /*环境变量在NAND FLASH的0x20000处*/

#define CFG_NAND_LEGACY 1
#define NFCE_LOW 0
#define NFCE_HIGH 1
#define NAND_MAX_CHIPS 1

#if (CONFIG_COMMANDS & CFG_CMD_NAND)
#define CFG_MAX_NAND_DEVICE 1 /* Max number of NAND devices */
#define CFG_NAND_BASE 0x4E000000
#define SECTORSIZE 512
#define ADDR_COLUMN 1
#define ADDR_PAGE 2
#define ADDR_COLUMN_PAGE 3

#define NAND_ChipID_UNKNOWN 0x00
#define NAND_MAX_FLOORS 1

#define NAND_WAIT_READY(nand) NF_WaitRB()
#define NAND_DISABLE_CE(nand) NF_SetCE(NFCE_HIGH)
#define NAND_ENABLE_CE(nand) NF_SetCE(NFCE_LOW)
#define WRITE_NAND_COMMAND(d, adr) NF_Cmd(d)
#define WRITE_NAND_COMMANDW(d, adr) NF_CmdW(d)
#define WRITE_NAND_ADDRESS(d, adr) NF_Addr(d)
#define WRITE_NAND(d, adr) NF_Write(d)
#define READ_NAND(adr) NF_Read()
/* the following functions are NOP's because S3C24X0 handles this in hardware */
#define NAND_CTL_CLRALE(nandptr)
#define NAND_CTL_SETALE(nandptr)
#define NAND_CTL_CLRCLE(nandptr)
#define NAND_CTL_SETCLE(nandptr)
/* #undef CONFIG_MTD_NAND_VERIFY_WRITE */
#endif /* CONFIG_COMMANDS & CFG_CMD_NAND */

#endif /* __CONFIG_H */

OK，编译烧写U-BOOT到NAND FLASH，就可以使用SAVEENV保存环境变量到NAND FLASH不丢失了。