JLink+GDBServer调试S3C6410裸板的初始化代码 For OK6410开发板

要调试裸板，有两种初始化方法，一个是用烧好的uboot初始化，再有就是直接用JLink+GDBServer初始化。代码参考了网上的资料，根据手头的OK6410开发板做了修改。整体代码如下：

# Connect to the J-Link GDBServer

target remote localhost:2331

# Set JTAG speed to 30 kHz

monitor endian little

monitor speed 30

# Reset the target

monitor reset

monitor sleep 10

#

# CPU core initialization 

#

# Set the processor to service mode

monitor reg cpsr = 0xd3

# Config MMU

# Flush v3/v4 cache

monitor cp15 7, 7, 0, 0 = 0x0

monitor cp15 8, 7, 0, 0 = 0x0

# Disable MMU stuff and caches

monitor cp15 1, 0, 0, 0 =0x1002

# Peri port setup

monitor cp15 15, 2, 0, 4 = 0x70000013

# Disable watchdog

monitor MemU32 0x7e004000  =  0x00000000

monitor sleep 10

# Disable interrupt

monitor MemU32 0x71200014  =  0xffffffff

monitor MemU32 0x71300014  =  0xffffffff

monitor MemU32 0x7120000C  =  0x00000000

monitor MemU32 0x7130000C  =  0x00000000

monitor MemU32 0x71200F00  =  0x00000000

monitor MemU32 0x71300F00  =  0x00000000

# Set clock 

monitor MemU32 0x7e00f900  =  0x000080de

monitor MemU32 0x7e00f000  =  0x0000ffff

monitor MemU32 0x7e00f004  =  0x0000ffff

monitor MemU32 0x7e00f008 = 0x0000ffff

monitor MemU32 0x7e00f028 = 0x00300000

monitor MemU32 0x7e00f020  =  0x01043310

monitor MemU32 0x7e00f00C  =  0x810a0301

monitor MemU32 0x7e00f010  =  0x810a0301

monitor MemU32 0x7e00f014 = 0x80200102

monitor MemU32 0x7e00f018 = 0x00000000

monitor MemU32 0x7e00f01c = 0x00000007

monitor sleep 1

# UART Init

monitor MemU32 0x7f008000 = 0x00220022

monitor memU32 0x7f008020 = 0x00002222

monitor memU32 0x7f005008 = 0x00000000

monitor memU32 0x7f00500c = 0x00000000

monitor memU32 0x7f005000 = 0x00000003

monitor memU32 0x7f005004 = 0x00000e45

monitor memU32 0x7f005028 = 0x00000033

monitor memU32 0x7f00502c = 0x0000dfdd

monitor memU32 0x7f005020 = 0x4f4f4f4f

monitor memU32 0x7f005020 = 0x4b4b4b4b

# Config Mobile DDR SDRAM

monitor MemU32 0x7e00f120  =  0x0000000d

monitor MemU32 0x7e001004  =  0x00000004

monitor MemU32 0x7e001010  =  0x0000040f

monitor MemU32 0x7e001014  =  0x00000006

monitor MemU32 0x7e001018  =  0x00000001

monitor MemU32 0x7e00101c  =  0x00000002

monitor MemU32 0x7e001020  =  0x00000006

monitor MemU32 0x7e001024  =  0x0000000a

monitor MemU32 0x7e001028  =  0x0000000c

monitor MemU32 0x7e00102c  =  0x0000010b

monitor MemU32 0x7e001030  =  0x0000000c

monitor MemU32 0x7e001034  =  0x00000002

monitor MemU32 0x7e001038  =  0x00000002

monitor MemU32 0x7e00103c  =  0x00000002

monitor MemU32 0x7e001040  =  0x00000002

monitor MemU32 0x7e001044  =  0x00000010

monitor MemU32 0x7e001048  =  0x00000010

monitor MemU32 0x7e00100C  =  0x0001001a

monitor MemU32 0x7e00104C  =  0x00000b45

monitor MemU32 0x7e001200  =  0x000150f0

monitor MemU32 0x7e001304  =  0x00000000

monitor MemU32 0x7e001008  =  0x000c0000

monitor MemU32 0x7e001008  =  0x00000000

monitor MemU32 0x7e001008  =  0x00040000

monitor MemU32 0x7e001008  =  0x00040000

monitor MemU32 0x7e001008  =  0x000a0000

monitor MemU32 0x7e001008  =  0x00080032

monitor MemU32 0x7e001004  =  0x00000000

# Setup GDB for faster downloads

#set remote memory-write-packet-size 1024

set remote memory-write-packet-size 4096

set remote memory-write-packet-size fixed

monitor speed 12000

break start_armboot

load

continue

下载逐行说明：

Monitor reg cpsr = 0xd3

这一行是把cpu置为管理模式，并且设置中断掩码I F T M4 M3 M2 M1 M0，对应于0xd3为0xB11010011， I、F置位设置中断及快速中断掩码， T清位，说明当前为ARM模式下， M置为0xB10011，为管理模式。

monitor MemU32 0x7e004000 = 0x00000000

这一行失能看门狗，该寄存器说明如下：

　　Watchdog timer [5]  0=Disable,  1=Enable

　　Clock select [4:3] 00:16  01:32  10:64  11:128

　　Interrupt generation [2] 0=Disable,  1=EnableReset enable/disable [0]

Monitor MemU32 0x71200014 = 0xFFFFFFFF

Monitor MemU32 0x71300014 = 0xFFFFFFFF

设置VIC0INTENCLEAR及VIC1IntENCLEAR寄存器，该寄存器写0无作用，写1会disable相应的中断：

　　Clears corresponding bits in the VICINTENABLE Register:0 = no effect1 = interrupt disabled in VICINTENABLE Register.There is one bit of the register for each interrupt source.

　　网上其它资料都是往里写0，应该是个错误。

Monitor MemU32 0x7120000C = 0x00000000

Monitor MemU32 0x7130000C = 0x00000000

设置所有中断为IRQ，而不是FIQ，该寄存器写0为IRQ，写1为FIQ：

　　Selects type of interrupt for interrupt request:0 = IRQ interrupt (reset)1 = FIQ interruptThere is one bit of the register for each interrupt source

Monitor MemU32 0x71200F00 = 0x00000000

Monitor MemU32 0x71300F00 = 0x00000000

设置VIC0ADDRERSS及VIC1ADDRESS寄存器，清除当前pending的中断:

　　Contains the address of the currently active ISR, with reset value0x00000000.A read of this register returns the address of the ISR and sets thecurrent interrupt as being serviced. A read must only be performedwhile there is an active interrupt.A write of any value to this register clears the current interrupt. Awrite must only be performed at the end of an interrupt serviceroutine.

Monitor MemU32 0x7e00f900 = 0x000080de

设置OTHERS寄存器为Synchronous mode，网上资料没有设置sync，要试验一下

Monitor MemU32 0x7e00f000 = 0x0000ffff

Monitor MemU32 0x7e00f004 = 0x0000ffff

Monitor MemU32 0x7e00f008 = 0x0000ffff

设置APLL_LOCK、MPLL_LOCK及EPLL_LOCK寄存器，都设为最大间隔

Monitor MemU32 0x7e00f028 = 0x00300000

设置CLK_DIV2寄存器，主要是设置UART_RATIO:       

　　UART_RATIO     [19:16]    

　　UART clock divider ratio

　　CLKUART = CLKUARTIN / (UART_RATIO + 1)

　　这里的设置是CLKUART = CLKUARTIN / 4

Monitor MemU32 0x7e00f020 = 0x01043310

设置CLK_DIV0寄存器, 设置的值如下     

　　PCLK_RATIO   [15:12]     0x3     

　　HCLKX2_RATIO [11:9]      0x1     

　　HCLK_RATIO   [8]         0x1     

　　MPLL_RATIO   [4]         0x1     

　　APLL_RATIO    [3:0]      0x0

　　根据如下的计算公式

　　PCLK = HCLKX2 / (PCLK_RATIO + 1)

　　HCLKX2 = HCLKX2IN / (HCLKX2_RATIO + 1)

　　HCLK = HCLKX2 / (HCLK_RATIO + 1)

　　DOUTMPLL = MOUTMPLL / (MPLL_RATIO + 1)

　　ARMCLK = DOUTAPLL / (ARM_RATIO + 1)

　　得到的计算结果 

　　PCLK = HCLKX2 / 4

　　HCLKX2 = HCLKX2IN / 2

　　HCLK = HCLKX2 / 2

　　DOUTMPLL = MOUTMPLL / 2

　　ARMCLK = DOUTAPLL  

Monitor MemU32 0x7e00f00c = 0x810a0301

Monitor MemU32 0x7e00f010 = 0x810a0301

设置APLL_CON及MPLL_CON寄存器，

　　计算公式为

　　FOUT = MDIV X FIN / (PDIV X 2SDIV)

　　对于APLL_CON寄存器：             

　　　　Enable   [31]         0x1             

　　　　MDIV    [25:16]   0x10a(266)             

　　　　PDIV     [13:8]    0x3             

　　　　SDIV     [2:0]     0x1

　　则FOUT = 266 X 12 / (3 X 2) = 532

　　对于MPLL_CON寄存器是一样的，也是532

Monitor MemU32 0x7e00f014 = 0x80200102

Monitor MemU32 0x7300f018 = 0x00000000

设置EPLL_CON0寄存器           

　　Enable      [31]    0x1           

　　MDIV       [23:16]   0x20           

　　PDIV       [13:8]   0x1           

　　SDIV       [2:0]    0x2

　　设置EPLL_CON1寄存器           

　　　　KDIV       [15:0]   0x0

　　根据计算公式：FOUT = (MDIV + KDIV / 216) X FIN / (PDIV X 2SDIV)

　　可以计算得到FOUT = 32 X 12 / (1 X 4) = 96

Monitor MemU32 0x7e00f01c = 0x00000007

　　设置CLK_SRC寄存器       

　　　　UART_SEL   [13]   0x0    using MOUT epll    

　　　　EPLL_SEL    [2]    0x1    using FOUT epll       

　　　　MPLL_SEL    [1]    0x1    using FOUT mpll       

　　　　APLL_SEL    [0]     0x1   using FOUT apll

Monitor MemU32 0x7f008000 = 0x00220022

　　设置GPACON寄存器     

　　　　GPA0         [3:0]     0x2   UART RXD[0]     

　　　　GPA1         [7:4]     0x2   UART TXD[0]     

　　　　GPA2         [11:8]    0x0   Input     

　　　　GPA3         [15:12]   0x0   Input     

　　　　GPA4         [19:16]   0x2   UART RXD[1]     

　　　　GPA5         [23:20]   0x2   UART TXD[1]

Monitor MemU32 0x7f008020 = 0x00002222

　　设置GPBCON寄存器     

　　　　GPB0     UART_RXD[2]     

　　　　GPB1     UART TXD[2]     

　　　　GPB2     UART RXD[3]     

　　　　GPB3     UART TXD[3]

Monitor memU32 0x7f005008 = 0x00000000

设置UFCON0寄存器：           

　　FIFO disable

Monitor memU32 0x7f00500c = 0x00000000

设置UMCON0寄存器：           

　　　　Modem interrupt Disable

Monitor MemU32 0x7f005000 = 0x00000003

设置ULCON0寄存器           

　　　　Word Length 8-bit           

　　　　One shop bit per frame           

　　　　No parity Mode           Normal mode operation

Monitor MemU32 0x7f005004 = 0x00000e45

设置UCON0寄存器           

　　　Clock selection EXT_UCLK1:  DIV_VAL=(EXT_UCLK1/(bps x16))-1           

　　Tx Interrupt Type: Level           

　　Rx Interrupt Type: Pulse           

　　Rx Time Out  Enable: disable           

　　Rx Error status interrupt enable: enable