NAND Flash驱动

硬件原理及分析

管脚说明

 
 

 
 

Pin Name	Pin Function
R/B(RnB)	The R/B output indicates the status of the device operation. When low, it indicates that a program, erase or random read operation is in process and returns to high state upon completion. It is an open drain output and does not float to high-z condition when the chip is deselected or when outputs are disabled.
CLE(CLE)	The CLE input controls the activating path for commands sent to the command register. When active high, commands are latched into the command register through the I/O ports on the rising edge of the WE signal.
CE(nFCE)	The CE input is the device selection control. When the device is in the Busy state, CE high is ignored, and the device does not return to standby mode in program or erase operation.
ALE(ALE)	The ALE input controls the activating path for address to the internal address registers. Addresses are latched on the rising edge of WE with ALE high.
WE(nFWE)	The WE input controls writes to the I/O port. Commands, address and data are latched on the rising edge of the WE pulse.
RE(nFRE)	The RE input is the serial data-out control, and when active drives the data onto the I/O bus. Data is valid tREA after the falling edge of RE which also increments the internal column address counter by one.
I/O(LDATA0-LDATA7)	The I/O pins are used to input command, address and data, and to output data during read operations. The I/O pins float to high-z when the chip is deselected or when the outputs are disabled.

 
 

在U-BOOT上操作Nand Flash

NAND FLASH
S3C2440

发命令 选中芯片

CLE设为高电平 NFCMMD=命令值

在DATA0~DATA7上输出命令值

发出一个写脉冲

 

发地址 选中芯片 NFADDR=地址值

ALE设为高电平

在DATA0~DATA7上输出地址值

发出一个写脉冲

 
 

发数据 选中芯片 NFDATA=数据值

ALE,CLE设为低电平

在DATA0~DATA7上输出数据值

发出一个写脉冲

 
 

读数据 选中芯片 val=NFDATA

发出读脉冲

读DATA0~DATA7的数据

 
 

 

OpenJTAG> help md

md [.b, .w, .l] address [# of objects]

- memory display

 
 

OpenJTAG> help mw

mw [.b, .w, .l] address value [count]

- write memory

•b        1字节

•W        2字节

•l        4字节

 

 
 

1. 读ID

S3C2440	u-boot
选中 NFCONT的bit1设为0	md.l 0x4E000004 1; mw.l 0x4E000004 1
发出命令0x90 NFCMMD=0x90	mw.b 0x4E000008 0x90
发出地址0x00 NFADDR=0x00	mw.b 0x4E00000C 0x00
读数据得到0xEC val=NFDATA	md.b 0x4E000010 1
读数据得到device code val=NFDATA	md.b 0x4E000010 1
退出读ID的状态 NFCMMD=0xff	mw.b 0x4E000008 0xff

 

2. 读内容: 读0地址的数据

使用UBOOT命令:

nand dump 0

Page 00000000 dump:

17 00 00 ea 14 f0 9f e5 14 f0 9f e5 14 f0 9f e5

 
 

S3C2440	u-boot
选中 NFCONT的bit1设为0	md.l 0x4E000004 1; mw.l 0x4E000004 1
发出命令0x00 NFCMMD=0x00	mw.b 0x4E000008 0x00
发出地址0x00 NFADDR=0x00	mw.b 0x4E00000C 0x00
发出地址0x00 NFADDR=0x00	mw.b 0x4E00000C 0x00
发出地址0x00 NFADDR=0x00	mw.b 0x4E00000C 0x00
发出地址0x00 NFADDR=0x00	mw.b 0x4E00000C 0x00
发出地址0x00 NFADDR=0x00	mw.b 0x4E00000C 0x00
发出命令0x30 NFCMMD=0x30	mw.b 0x4E000008 0x30
读数据得到0x17 val=NFDATA	md.b 0x4E000010 1
读数据得到0x00 val=NFDATA	md.b 0x4E000010 1
读数据得到0x00 val=NFDATA	md.b 0x4E000010 1
读数据得到0xea val=NFDATA	md.b 0x4E000010 1
退出读状态 NFCMMD=0xff	mw.b 0x4E000008 0xff

 
 

ECC的作用

 

 

 

S3C2440-Nand Flash Controller Register

 

 
 

S3C2440-Nand Flash Memory Timing

 
 

K9F2G08U0C-Key Characteristic

 
 

K9F2G08U0C-Operation Timing

 
 

 
 

驱动程序

driver.c

1         
19         
24         
26

29                                                                                                                                                 };
47

48

52         []                 .name                          .size                          .offset         },
59

60         []                 .name                          .offset                 .size                  },
65

66         []                 .name                          .offset                 .size                  },
71

72         []                 .name                          .offset                 .size                  },
77 };
78

79 {
81                  {
83                                  regs_nand         }
86                                           regs_nand         }
90          }
92

93 {
95                  {
97                                  regs_nand         }
100                  {
102                                  regs_nand         }
105          }
107

108 {
110          }
112

113

114 {
117         

119                  nand         

123         regs_nand

125                           nand         nand         nand         nand         nand         nand         

135                           clk         clk_enable(clk);
139         
140                  regs_nand

146                  regs_nand                  
150

151                  mtd         mtd         mtd         
156         nand_scan(mtd, );                         

159

160                  add_mtd_partitions(mtd, nand_parts, );
162

163                           

167         ;
168 }
169

170 {
172         del_mtd_partitions(mtd);
173         kfree(nand);
174         kfree(mtd);
175         iounmap(regs_nand);
176          }
178

179 module_init(nand_init);
180 module_exit(nand_exit);
181 MODULE_LICENSE("GPL");
182 /******** 1 end ********/

 

Makefile

1

3         make -C

6         make -C         rm -rf modules.order
9

10 obj-m        += nand_drv.o

 
 

 
 

 
 

调试

pc-linux:

//格式化工具

tar xjf mtd-utils-05.07.23.tar.bz2

cd mtd-utils-05.07.23/util

修改Makefile:

#CROSS=arm-linux-

改为

CROSS=arm-linux-

make

cp flash_erase flash_eraseall /work/nfs_root/fs_mini/bin/

//格式化工具-----end

 
 

board-uboot：

nfs 30000000 192.168.0.103:/work/nfs_root/uImage_f

//使用NFS作为根文件系统

set bootargs console=ttySAC0 root=/dev/nfs nfsroot=192.168.0.103:/work/nfs_root/fs_mini ip=192.168.0.33:192.168.0.103:192.168.0.1:255.255.255.0::eth0:off

bootm 30000000

 
 

board-linux：

insmod nand_drv.ko

 
 

flash_eraseall /dev/mtd3 // yaffs //格式化

mount -t yaffs /dev/mtdblock3 /mnt
//挂接