Linux 3.3.0移植到S3C6410开发板上之一

这里仅仅是移植成功内核，可以挂载文件系统运行，至于驱动会陆续添加。

第一步：到内核官网上下载最新的内核，我下载的是linux-3.3-rc3.tar.bz2。

第二步：解压内核，进入arch/arm/mach-s3c64xx目录下，看到不少6410的板级文件，我们这里选择mini6410开开展工作，在目录下将mach-mini6410.c文件复制一份，命名为：mach-jfj6410.c。这里我们将文件里面关于mini6410的字样都修改为jfj6410.但是这里要注意，MACHINE_START(JFJ6410, "JFJ6410")这里的JFJ6410要使用大写，稍候说明为什么。大家都知道在一个目录下添加了文件后，都应该修改当前目录下的Kconfig和Makefile两个文件，这是Linux系统编译的要求。至于怎么修改，仔细看一下文件内容我相信大家都知道。

Kconfig文件是进行make menuconfig时出现的配置选项，这里我们添加了自己的板级文件肯定要添加配置选项。内容可以复制MINI6410的。如下：

config MACH_JFJ6410
bool "JFJ6410"
select CPU_S3C6410
select S3C_DEV_HSMMC
select S3C_DEV_HSMMC1
select S3C64XX_SETUP_SDHCI
select S3C_DEV_USB_HOST
select S3C_DEV_NAND
select S3C_DEV_FB
select S3C64XX_SETUP_FB_24BPP
select SAMSUNG_DEV_ADC
select SAMSUNG_DEV_TS
help
Machine support for the JFJKJ JFJ6410

这里你应该能够看出之前为什么要在那个地方单独使用大写了吧，就是为了保持一致。

Makefile文件就是说明要编译的文件，以及编译的规则，这里显然就是要编译我们自己的板级文件mach-jfj6410.c，具体如下：

obj-$(CONFIG_MACH_JFJ6410)		+= mach-jfj6410.o

第三步：配置内核，make menuconfig。这里我是使用内核自带的s3c6400_defconfig文件进行修改的，这样比较简单，呵呵。基本去掉了大部分的驱动，留下了串口驱动和NAND驱动。

第四步：编译make zImage。呵呵，这样就生成了我们需要的内核。

第五步：烧写，测试内核。因为我们是测试内核，所以U-Boot以及根文件系统都是使用之前的，这里没有移植yaffs，所以我目前使用cramfs格式的文件系统。

启动开发板后出现了如下的错误：

end_request: I/O error, dev mtdblock2, sector 0
FAT: unable to read boot sector
VFS: Cannot open root device "mtdblock2" or unknown-block(31,2)
Please append a correct "root=" boot option; here are the available partitions:
1f00        192 mtdblock0 (driver?)
1f01       1856 mtdblock1 (driver?)
1f02      30720 mtdblock2 (driver?)
1f03      32768 mtdblock3 (driver?)
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(31,2)

后来上网查了很久才发现是驱动的问题。U-boot使用软件ECC，我们在配置NAND驱动的时候提示是否选择使用NAND硬件ECC，我试了一下，无论你选不选都出现这个问题，我才发现，它的配置包含三重含义，选中--->使用硬件ECC；不选--->使用NAND的软件ECC(和U-Boot的软件ECC不是一回事)；而我们这里需要的是不使用NAND的ECC，也就是禁止，不然就会和U-Boot冲突，出现上面的错误。要禁止NAND的ECC，我们修改drivers/mtd/nand/s3c2410.c这个文件，在845行的地方。

源代码为：

chip->ecc.mode = NAND_ECC_SOFT;

修改为：

chip->ecc.mode	= NAND_ECC_NONE;

这就是当我们不选中的时候，不是使用NAND的软件ECC，而是不使用NAND的ECC。

再次编译内核，烧写后正常运行，打印的信息如下：

Starting kernel ...

Uncompressing Linux... done, booting the kernel.
Booting Linux on physical CPU 0
Linux version 3.3.0-rc3 (chenlong12580@chenlong12580) (gcc version 4.3.2 (Sourcery G++ Lite 2008q3-72) ) #4 Mon Feb 13 14:58:00 CST 2012
CPU: ARMv6-compatible processor [410fb766] revision 6 (ARMv7), cr=00c5387d
CPU: PIPT / VIPT nonaliasing data cache, VIPT nonaliasing instruction cache
Machine: JFJ6410
Memory policy: ECC disabled, Data cache writeback
CPU S3C6410 (id 0x36410101)
S3C24XX Clocks, Copyright 2004 Simtec Electronics
camera: no parent clock specified
S3C64XX: PLL settings, A=532000000, M=532000000, E=24000000
S3C64XX: HCLK2=266000000, HCLK=133000000, PCLK=66500000
mout_apll: source is fout_apll (1), rate is 532000000
mout_epll: source is epll (1), rate is 24000000
mout_mpll: source is mpll (1), rate is 532000000
usb-bus-host: source is clk_48m (0), rate is 48000000
audio-bus: source is mout_epll (0), rate is 24000000
audio-bus: source is mout_epll (0), rate is 24000000
audio-bus: source is mout_epll (0), rate is 24000000
irda-bus: source is mout_epll (0), rate is 24000000
camera: no parent clock specified
CPU: found DTCM0 8k @ 00000000, not enabled
CPU: moved DTCM0 8k to fffe8000, enabled
CPU: found DTCM1 8k @ 00000000, not enabled
CPU: moved DTCM1 8k to fffea000, enabled
CPU: found ITCM0 8k @ 00000000, not enabled
CPU: moved ITCM0 8k to fffe0000, enabled
CPU: found ITCM1 8k @ 00000000, not enabled
CPU: moved ITCM1 8k to fffe2000, enabled
Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 65024
Kernel command line: root=/dev/mtdblock2 rootfstype=cramfs console=ttySAC0,115200
PID hash table entries: 1024 (order: 0, 4096 bytes)
Dentry cache hash table entries: 32768 (order: 5, 131072 bytes)
Inode-cache hash table entries: 16384 (order: 4, 65536 bytes)
Memory: 256MB = 256MB total
Memory: 257500k/257500k available, 4644k reserved, 0K highmem
Virtual kernel memory layout:
vector  : 0xffff0000 - 0xffff1000   (   4 kB)
DTCM    : 0xfffe8000 - 0xfffec000   (  16 kB)
ITCM    : 0xfffe0000 - 0xfffe4000   (  16 kB)
fixmap  : 0xfff00000 - 0xfffe0000   ( 896 kB)
vmalloc : 0xd0800000 - 0xff000000   ( 744 MB)
lowmem  : 0xc0000000 - 0xd0000000   ( 256 MB)
modules : 0xbf000000 - 0xc0000000   (  16 MB)
.text : 0xc0008000 - 0xc01d90b8   (1861 kB)
.init : 0xc01da000 - 0xc01f5000   ( 108 kB)
.data : 0xc01f6000 - 0xc0216a40   ( 131 kB)
.bss : 0xc0217024 - 0xc0246c58   ( 192 kB)
SLUB: Genslabs=13, HWalign=32, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
NR_IRQS:246
VIC @f6000000: id 0x00041192, vendor 0x41
VIC @f6010000: id 0x00041192, vendor 0x41
Console: colour dummy device 80x30
Calibrating delay loop... 528.79 BogoMIPS (lpj=2643968)
pid_max: default: 32768 minimum: 301
Mount-cache hash table entries: 512
CPU: Testing write buffer coherency: ok
Setting up static identity map for 0x5015e320 - 0x5015e37c
gpiochip_add: registered GPIOs 38 to 53 on device: GPF
gpiochip_add: registered GPIOs 74 to 89 on device: GPI
gpiochip_add: registered GPIOs 91 to 102 on device: GPJ
gpiochip_add: registered GPIOs 161 to 176 on device: GPO
gpiochip_add: registered GPIOs 178 to 192 on device: GPP
gpiochip_add: registered GPIOs 194 to 202 on device: GPQ
gpiochip_add: registered GPIOs 144 to 159 on device: GPN
gpiochip_add: registered GPIOs 0 to 7 on device: GPA
gpiochip_add: registered GPIOs 9 to 15 on device: GPB
gpiochip_add: registered GPIOs 17 to 24 on device: GPC
gpiochip_add: registered GPIOs 26 to 30 on device: GPD
gpiochip_add: registered GPIOs 32 to 36 on device: GPE
gpiochip_add: registered GPIOs 55 to 61 on device: GPG
gpiochip_add: registered GPIOs 137 to 142 on device: GPM
gpiochip_add: registered GPIOs 63 to 72 on device: GPH
gpiochip_add: registered GPIOs 104 to 119 on device: GPK
gpiochip_add: registered GPIOs 121 to 135 on device: GPL
jfj6410: Option string jfj6410=0
jfj6410: selected LCD display is 480x272
S3C6410: Initialising architecture
bio: create slab <bio-0> at 0
io scheduler noop registered
io scheduler deadline registered
io scheduler cfq registered (default)
start plist test
end plist test
Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled
s3c6400-uart.0: ttySAC0 at MMIO 0x7f005000 (irq = 69) is a S3C6400/10
console [ttySAC0] enabled
s3c6400-uart.1: ttySAC1 at MMIO 0x7f005400 (irq = 70) is a S3C6400/10
s3c6400-uart.2: ttySAC2 at MMIO 0x7f005800 (irq = 71) is a S3C6400/10
s3c6400-uart.3: ttySAC3 at MMIO 0x7f005c00 (irq = 72) is a S3C6400/10
brd: module loaded
loop: module loaded
S3C24XX NAND Driver, (c) 2004 Simtec Electronics
s3c24xx-nand s3c6400-nand: Tacls=4, 30ns Twrph0=8 60ns, Twrph1=6 45ns
s3c24xx-nand s3c6400-nand: System booted from NAND
s3c24xx-nand s3c6400-nand: NAND ECC disabled
NAND device: Manufacturer ID: 0xec, Chip ID: 0xda (Samsung NAND 256MiB 3,3V 8-bit)
NAND_ECC_NONE selected by board driver. This is not recommended!
Scanning device for bad blocks
Bad eraseblock 1050 at 0x000008340000
Bad eraseblock 1076 at 0x000008680000
Bad eraseblock 1211 at 0x000009760000
Bad eraseblock 1949 at 0x00000f3a0000
Creating 4 MTD partitions on "nand":
0x000000000000-0x000000100000 : "Bootloader"
0x000000100000-0x000000600000 : "Kernel"
0x000000600000-0x000007e00000 : "User"
0x000007e00000-0x000010000000 : "File System"
mousedev: PS/2 mouse device common for all mice
VFP support v0.3: implementor 41 architecture 1 part 20 variant b rev 5
VFS: Mounted root (cramfs filesystem) readonly on device 31:2.
Freeing init memory: 108K
mount: mounting none on /proc/bus/usb failed: No such file or directory
hwclock: can't open '/dev/misc/rtc': No such file or directory
depmod: chdir(3.3.0-rc3): No such file or directory
[01/Jan/1970:00:00:07 +0000] boa.c:173 - unable to create socket: Function not implemented

open device leds: No such file or directory
/usr/sbin/alsactl: load_state:1610: No soundcards found...

ifconfig: socket: Function not implemented
Try to bring eth0 interface up......cat: can't open '/sys/class/net/eth0/address': No such file or directory
ifconfig: socket: Function not implemented
route: socket: Function not implemented
/etc/init.d/ifconfig-eth0: line 6: can't create /etc/resolv.conf: Read-only file system
Done

Please press Enter to activate this console.
[root@JFJ6410 /]# ls
bin      etc      lib      mnt      proc     sbin     tmp      var
dev      home     linuxrc  opt      root     sys      usr      www
[root@JFJ6410 /]#

驱动的添加，敬请期待。。。。