1JFFS2 options and usage. 2----------------------- 3 4JFFS2 in U-Boot is a read only implementation of the file system in 5Linux with the same name. To use JFFS2 define CONFIG_CMD_JFFS2. 6 7The module adds three new commands. 8fsload - load binary file from a file system image 9fsinfo - print information about file systems 10ls - list files in a directory 11chpart - change active partition 12 13If you boot from a partition which is mounted writable, and you 14update your boot environment by replacing single files on that 15partition, you should also define CFG_JFFS2_SORT_FRAGMENTS. Scanning 16the JFFS2 filesystem takes *much* longer with this feature, though. 17Sorting is done while inserting into the fragment list, which is 18more or less a bubble sort. That algorithm is known to be O(n^2), 19thus you should really consider if you can avoid it! 20 21 22There is two ways for JFFS2 to find the disk. The default way uses 23the flash_info structure to find the start of a JFFS2 disk (called 24partition in the code) and you can change where the partition is with 25two defines. 26 27CFG_JFFS2_FIRST_BANK 28 defined the first flash bank to use 29 30CFG_JFFS2_FIRST_SECTOR 31 defines the first sector to use 32 33 34The second way is to define CFG_JFFS_CUSTOM_PART and implement the 35jffs2_part_info(int part_num) function in your board specific files. 36In this mode CFG_JFFS2_FIRST_BANK and CFG_JFFS2_FIRST_SECTOR is not 37used. 38 39The input is a partition number starting with 0. 40Return a pointer to struct part_info or NULL for error; 41 42Ex jffs2_part_info() for one partition. 43--- 44#if defined CFG_JFFS_CUSTOM_PART 45#include <jffs2/jffs2.h> 46 47static struct part_info part; 48 49struct part_info* 50jffs2_part_info(int part_num) 51{ 52 if(part_num==0){ 53 if(part.usr_priv==(void*)1) 54 return ∂ 55 56 memset(&part, 0, sizeof(part)); 57 part.offset=(char*)0xFF800000; 58 part.size=1024*1024*8; 59 60 /* Mark the struct as ready */ 61 part.usr_priv=(void*)1; 62 63 return ∂ 64 } 65 return 0; 66} 67#endif 68--- 69 70TODO. 71 72 Remove the assumption that JFFS can dereference a pointer 73 into the disk. The current code do not work with memory holes 74 or hardware with a sliding window (PCMCIA). 75