U-boot操作Flash (NOR, NAND & SPI)

uboot中操作三种flash的命令集：

Action	NOR	NAND	SPI
Copy Flash to RAM	cp.[bwl]	nand read	eeprom read
Write to Flash from RAM	cp.[bwl]	nand write	eeprom write
Dump Flash	md.[bwl]	nand dump	eeprom read ; md.[bwl]
Ease Flash	erase	nand erase	n/a
Write Protection	protect on protect off	nand lock nand unlock	n/a
Additional Info	flinfo imls	nand info nand bad	n/a

uboot中查看命令帮助：

MB680> help cp
MB680> help nand
MB680> help eeprom

nor烧写命令：

MB680> nfs $load_addr /export/u-boot.bin
MB680> protect off 1:0-4
MB680> erase 1:0-4
MB680> cp.b $load_addr A0000000 $filesize
MB680> protect on 1:0-4

nor烧写内置命令：

MB680> nfs $load_addr /export/u-boot.bin
MB680> run unprot
MB680> run update

nand烧写命令：

MB680> nfs $load_addr /export/u-boot.bin
MB680> nand erase 0 40000
MB680> nand write $load_addr 0 40000

uboot启动内核的时候使用的命令是nand read.i c0008000 80000 500000;bootm c0008000

在nand中0x80000处开始的5M的数据拷到sdram0xc0008000处，从这个地址开始执行。

spi烧写命令：

MB680> nfs $load_addr /export/u-boot.bin
MB680> eeprom write $load_addr 0 $filesize