Hi; I recently ran into the problem of overwriting the content of flash used to store the code sections for my PQ2FADS-ZU board. When I `setenv` and `saveenv` some parameters into the flash, type `res` and nothing happens. When I dig around, it was due to the fact that CFG_ENV_ADDR was statically defined in include/configs/*. In the case of my board which is using MPC8260ADS.h,
#ifndef CFG_RAMBOOT # define CFG_ENV_IS_IN_FLASH 1 # define CFG_ENV_SECT_SIZE 0x40000 # define CFG_ENV_ADDR (CFG_MONITOR_BASE + CFG_ENV_SECT_SIZE) #else <snip> #endif
What happens is that the size of u-boot loaded into the flash of my board occupies more than one sector of the flash and CFG_ENV_ADDR is located at the second sector of the flash imimediately following u-boot with the flash sector size of 0x40000:
8280>unlock 0xfff00000 0x40000 2 8280>erase Erasing flash at 0xfff00000 Erasing flash at 0xfff40000 Erasing flash passed 8280>prog 0 u-boot elf Programming u-boot , please wait .... - File offset 0x00000078 to address 0xFFF00000 size 296544 Programming flash passed 8280>
[teh@ShrekII u-boot 10]$ size /tftpboot/u-boot text data bss dec hex filename 276384 18012 252920 547316 859f4 /tftpboot/u-boot [teh@ShrekII u-boot 11]$
In fact CFG_ENV_ADDR is statically defined in all of the config files in ./include/configs/*. I wonder if it is possible to use an external _end symbol as the start address for environmental flash section. But then, when I check System.map and with `md` command in BDI2000, _end happens too long after any meaningful content of u-boot in flash:
[teh@ShrekII u-boot 12]$ tail System.map fff56994 B ide_dev_desc fff569f8 B os_data_header fff56a18 B send_parms fff56a2c B hose fff56b00 B flash_info fff56bac B super fff56bf8 B get_vfatname_block fff66bf8 B get_dentfromdir_block fff76bf8 B do_fat_read_block fff86bf8 A _end [teh@ShrekII u-boot 13]$
8280>md 0xfff48600 fff48600 : fff3f030 00000010 00000001 fff17130 ...0..........q0 fff48610 : fff3f038 fff3f060 fff3f084 00000002 ...8...`........ fff48620 : 00000001 fff175c4 fff3f08c fff3f0a4 ......u......... fff48630 : fff3f130 00000010 00000001 fff17604 ...0..........v. fff48640 : fff3f138 fff3f158 fff3f288 00000010 ...8...X........ fff48650 : 00000001 fff17604 fff3f28c 00000000 ......v......... fff48660 : ffffffff ffffffff ffffffff ffffffff ................ fff48670 : ffffffff ffffffff ffffffff ffffffff ................ fff48680 : ffffffff ffffffff ffffffff ffffffff ................ fff48690 : ffffffff ffffffff ffffffff ffffffff ................ fff486a0 : ffffffff ffffffff ffffffff ffffffff ................ fff486b0 : ffffffff ffffffff ffffffff ffffffff ................ fff486c0 : ffffffff ffffffff ffffffff ffffffff ................ fff486d0 : ffffffff ffffffff ffffffff ffffffff ................ fff486e0 : ffffffff ffffffff ffffffff ffffffff ................ fff486f0 : ffffffff ffffffff ffffffff ffffffff ................ 8280>
As shown, the flash content from 0xFFF48660 (the size of u-boot shown when loading it into the flash) to _end @0xFFF86BF8 is 0xFF. If I define the start address of env flash to be _end, there is too much space to be wasted in the flash while in fact the environment parameters can start at 0xFFF80000 which is the third sector after u-boot content in the flash. My question is if it is possible to dynamically define the start address of environment parameters in the flash and if it is, how to achieve it..? Any insight is appreciated.
Regards, TEH