历史上的今天
今天是：2024年10月12日（星期六）
2018年10月12日 | 自己写bootloader倒计时启动内核
2018-10-12 来源：eefocus
start.S源码：
.global _start
_start:
ldr sp, =0xD0030000 // 初始化栈，因为后面要调用C函数
bl clock_init // 初始化时钟
bl ddr_init // 初始化内存
bl nand_init // 初始化NAND
ldr r0, =0x36000000 // 要拷贝到DDR中的位置
ldr r1, =0x0 // 从NAND的0地址开始拷贝
ldr r2, =bss_start // BSS段的开始地址
sub r2,r2,r0 // 要拷贝的大小
bl nand_read // 拷贝数据
clean_bss:
ldr r0, =bss_start
ldr r1, =bss_end
mov r3, #0
cmp r0, r1
ldreq pc, =on_ddr
clean_loop:
str r3, [r0], #4
cmp r0, r1
bne clean_loop
ldr pc, =on_ddr
on_ddr:
ldr sp, =0x33000000 // 重新初始化栈，指向内存
ldr pc, =main
===================================================================
clock.c源码：
#define APLL_CON (*(volatile unsigned int *)0xe0100100)
#define CLK_SRC0 (*(volatile unsigned int *)0xe0100200)
#define CLK_DIV0 (*(volatile unsigned int *)0xe0100300)
#define MPLL_CON (*(volatile unsigned int *)0xe0100108)
void clock_init(void)
{
// 设置时钟为:
// ARMCLK=1000MHz, HCLKM=200MHz, HCLKD=166.75MHz
// HCLKP =133.44MHz, PCLKM=100MHz, PCLKD=83.375MHz,
// PCLKP =66.7MHz
// SDIV[2:0] : S = 1
// PDIV[13:8] : P = 0x3
// MDIV[25:16]: M = 0x7d
// LOCKED [29]: 1 = 使能锁
// ENABLE [31]: 1 = 使能APLL控制器
// 得出FoutAPLL = 500MHz
APLL_CON = (1<<31)|(1<<29)|(0x7d<<16)|(0x3<<8)|(1<<0);
// 时钟源的设置
// APLL_SEL[0] :1 = FOUTAPLL
// MPLL_SEL[4] :1 = FOUTMPLL
// EPLL_SEL[8] :1 = FOUTEPLL
// VPLL_SEL[12]:1 = FOUTVPLL
// MUX_MSYS_SEL[16]:0 = SCLKAPLL
// MUX_DSYS_SEL[20]:0 = SCLKMPLL
// MUX_PSYS_SEL[24]:0 = SCLKMPLL
// ONENAND_SEL [28]:1 = HCLK_DSYS
CLK_SRC0 = (1<<28)|(1<<12)|(1<<8)|(1<<4)|(1<<0);
// 设置分频系数
// APLL_RATIO[2:0]: APLL_RATIO = 0x0
// A2M_RATIO [6:4]: A2M_RATIO = 0x4
// HCLK_MSYS_RATIO[10:8]: HCLK_MSYS_RATIO = 0x4
// PCLK_MSYS_RATIO[14:12]:PCLK_MSYS_RATIO = 0x1
// HCLK_DSYS_RATIO[19:16]:HCLK_DSYS_RATIO = 0x3
// PCLK_DSYS_RATIO[22:20]:PCLK_DSYS_RATIO = 0x1
// HCLK_PSYS_RATIO[27:24]:HCLK_PSYS_RATIO = 0x4
// PCLK_PSYS_RATIO[30:28]:PCLK_PSYS_RATIO = 0x1
CLK_DIV0 = (0x1<<28)|(0x4<<24)|(0x1<<20)|(0x3<<16)|(0x1<<12)|(0x4<<8)|(0x4<<4);
// SDIV[2:0] : S = 1
// PDIV[13:8] : P = 0xc
// MDIV[25:16]: M = 0x29b
// VSEL [27]: 0
// LOCKED [29]: 1 = 使能锁
// ENABLE [31]: 1 = 使能MPLL控制器
// 得出FoutAPLL = 667MHz
APLL_CON = (1<<31)|(1<<29)|(0x29d<<16)|(0xc<<8)|(1<<0);
}
=====================================================================
mem_setup.S源码：
// SDRAM Controller
#define APB_DMC_0_BASE 0xF0000000
#define APB_DMC_1_BASE 0xF1400000
#define ASYNC_MSYS_DMC0_BASE 0xF1E00000
#define ELFIN_GPIO_BASE 0xE0200000
// MemControl BL=4, 1Chip, DDR2 Type, dynamic self refresh, force precharge, dynamic power down off
#define DMC0_MEMCONTROL 0x00202400
// MemConfig0 256MB config, 8 banks,Mapping Method[12:15]0:linear, 1:linterleaved, 2:Mixed
#define DMC0_MEMCONFIG_0 0x20E00323
#define DMC0_MEMCONFIG_1 0x00E00323 // MemConfig1
// TimingAref 7.8us*133MHz=1038(0x40E), 100MHz=780(0x30C), 20MHz=156(0x9C), 10MHz=78(0x4E)
#define DMC0_TIMINGA_REF 0x00000618
#define DMC0_TIMING_ROW 0x2B34438A // TimingRow for @200MHz
#define DMC0_TIMING_DATA 0x24240000 // TimingData CL=3
#define DMC0_TIMING_PWR 0x0BDC0343 // TimingPower
// MemControl BL=4, 2 chip, DDR2 type, dynamic self refresh, force precharge, dynamic power down off
#define DMC1_MEMCONTROL 0x00202400
// MemConfig0 512MB config, 8 banks,Mapping Method[12:15]0:linear, 1:linterleaved, 2:Mixed
#define DMC1_MEMCONFIG_0 0x40F00313
#define DMC1_MEMCONFIG_1 0x00F00313 // MemConfig1
// TimingAref 7.8us*133MHz=1038(0x40E), 100MHz=780(0x30C), 20MHz=156(0x9C), 10MHz=78(0x4E)
#define DMC1_TIMINGA_REF 0x00000618
#define DMC1_TIMING_ROW 0x2B34438A // TimingRow for @200MHz
#define DMC1_TIMING_DATA 0x24240000 // TimingData CL=3
#define DMC1_TIMING_PWR 0x0BDC0343 // TimingPower
#define MP1_0DRV_SR_OFFSET 0x3CC
#define MP1_1DRV_SR_OFFSET 0x3EC
#define MP1_2DRV_SR_OFFSET 0x40C
#define MP1_3DRV_SR_OFFSET 0x42C
#define MP1_4DRV_SR_OFFSET 0x44C
#define MP1_5DRV_SR_OFFSET 0x46C
#define MP1_6DRV_SR_OFFSET 0x48C
#define MP1_7DRV_SR_OFFSET 0x4AC
#define MP1_8DRV_SR_OFFSET 0x4CC
#define MP2_0DRV_SR_OFFSET 0x4EC
#define MP2_1DRV_SR_OFFSET 0x50C
#define MP2_2DRV_SR_OFFSET 0x52C
#define MP2_3DRV_SR_OFFSET 0x54C
#define MP2_4DRV_SR_OFFSET 0x56C
#define MP2_5DRV_SR_OFFSET 0x58C
#define MP2_6DRV_SR_OFFSET 0x5AC
#define MP2_7DRV_SR_OFFSET 0x5CC
#define MP2_8DRV_SR_OFFSET 0x5EC
#define DMC_CONCONTROL 0x00
#define DMC_MEMCONTROL 0x04
#define DMC_MEMCONFIG0 0x08
#define DMC_MEMCONFIG1 0x0C
#define DMC_DIRECTCMD 0x10
#define DMC_PRECHCONFIG 0x14
#define DMC_PHYCONTROL0 0x18
#define DMC_PHYCONTROL1 0x1C
#define DMC_RESERVED 0x20
#define DMC_PWRDNCONFIG 0x28
#define DMC_TIMINGAREF 0x30
#define DMC_TIMINGROW 0x34
#define DMC_TIMINGDATA 0x38
#define DMC_TIMINGPOWER 0x3C
#define DMC_PHYSTATUS 0x40
#define DMC_CHIP0STATUS 0x48
#define DMC_CHIP1STATUS 0x4C
#define DMC_AREFSTATUS 0x50
#define DMC_MRSTATUS 0x54
#define DMC_PHYTEST0 0x58
#define DMC_PHYTEST1 0x5C
#define DMC_QOSCONTROL0 0x60
#define DMC_QOSCONFIG0 0x64
#define DMC_QOSCONTROL1 0x68
#define DMC_QOSCONFIG1 0x6C
#define DMC_QOSCONTROL2 0x70
#define DMC_QOSCONFIG2 0x74
#define DMC_QOSCONTROL3 0x78
#define DMC_QOSCONFIG3 0x7C
#define DMC_QOSCONTROL4 0x80
#define DMC_QOSCONFIG4 0x84
#define DMC_QOSCONTROL5 0x88
#define DMC_QOSCONFIG5 0x8C
#define DMC_QOSCONTROL6 0x90
#define DMC_QOSCONFIG6 0x94
#define DMC_QOSCONTROL7 0x98
#define DMC_QOSCONFIG7 0x9C
#define DMC_QOSCONTROL8 0xA0
#define DMC_QOSCONFIG8 0xA4
#define DMC_QOSCONTROL9 0xA8
#define DMC_QOSCONFIG9 0xAC
#define DMC_QOSCONTROL10 0xB0
#define DMC_QOSCONFIG10 0xB4
#define DMC_QOSCONTROL11 0xB8
#define DMC_QOSCONFIG11 0xBC
#define DMC_QOSCONTROL12 0xC0
#define DMC_QOSCONFIG12 0xC4
#define DMC_QOSCONTROL13 0xC8
#define DMC_QOSCONFIG13 0xCC
#define DMC_QOSCONTROL14 0xD0
#define DMC_QOSCONFIG14 0xD4
#define DMC_QOSCONTROL15 0xD8
#define DMC_QOSCONFIG15 0xDC
// SDRAM Controller
#define APB_DMC_0_BASE 0xF0000000
#define APB_DMC_1_BASE 0xF1400000
#define ASYNC_MSYS_DMC0_BASE 0xF1E00000
#define DMC_CONCONTROL 0x00
#define DMC_MEMCONTROL 0x04
#define DMC_MEMCONFIG0 0x08
#define DMC_MEMCONFIG1 0x0C
#define DMC_DIRECTCMD 0x10
#define DMC_PRECHCONFIG 0x14
#define DMC_PHYCONTROL0 0x18
#define DMC_PHYCONTROL1 0x1C
#define DMC_RESERVED 0x20
#define DMC_PWRDNCONFIG 0x28
#define DMC_TIMINGAREF 0x30
#define DMC_TIMINGROW 0x34
#define DMC_TIMINGDATA 0x38
#define DMC_TIMINGPOWER 0x3C
#define DMC_PHYSTATUS 0x40
#define DMC_CHIP0STATUS 0x48
#define DMC_CHIP1STATUS 0x4C
#define DMC_AREFSTATUS 0x50
#define DMC_MRSTATUS 0x54
#define DMC_PHYTEST0 0x58
#define DMC_PHYTEST1 0x5C
#define DMC_QOSCONTROL0 0x60
#define DMC_QOSCONFIG0 0x64
#define DMC_QOSCONTROL1 0x68
#define DMC_QOSCONFIG1 0x6C
#define DMC_QOSCONTROL2 0x70
#define DMC_QOSCONFIG2 0x74
#define DMC_QOSCONTROL3 0x78
#define DMC_QOSCONFIG3 0x7C
#define DMC_QOSCONTROL4 0x80
#define DMC_QOSCONFIG4 0x84
#define DMC_QOSCONTROL5 0x88
#define DMC_QOSCONFIG5 0x8C
#define DMC_QOSCONTROL6 0x90
#define DMC_QOSCONFIG6 0x94
#define DMC_QOSCONTROL7 0x98
#define DMC_QOSCONFIG7 0x9C
#define DMC_QOSCONTROL8 0xA0
#define DMC_QOSCONFIG8 0xA4
#define DMC_QOSCONTROL9 0xA8
#define DMC_QOSCONFIG9 0xAC
#define DMC_QOSCONTROL10 0xB0
#define DMC_QOSCONFIG10 0xB4
#define DMC_QOSCONTROL11 0xB8
#define DMC_QOSCONFIG11 0xBC
#define DMC_QOSCONTROL12 0xC0
#define DMC_QOSCONFIG12 0xC4
#define DMC_QOSCONTROL13 0xC8
#define DMC_QOSCONFIG13 0xCC
#define DMC_QOSCONTROL14 0xD0
#define DMC_QOSCONFIG14 0xD4
#define DMC_QOSCONTROL15 0xD8
#define DMC_QOSCONFIG15 0xDC
.globl ddr_init
ddr_init:
// DMC0 Drive Strength (Setting 2X)
ldr r0, =ELFIN_GPIO_BASE
ldr r1, =0x0000AAAA
str r1, [r0, #0x3cc]
str r1, [r0, #MP1_0DRV_SR_OFFSET]
ldr r1, =0x0000AAAA
str r1, [r0, #MP1_1DRV_SR_OFFSET]
ldr r1, =0x0000AAAA
str r1, [r0, #MP1_2DRV_SR_OFFSET]
ldr r1, =0x0000AAAA
str r1, [r0, #MP1_3DRV_SR_OFFSET]
ldr r1, =0x0000AAAA
str r1, [r0, #MP1_4DRV_SR_OFFSET]
ldr r1, =0x0000AAAA
str r1, [r0, #MP1_5DRV_SR_OFFSET]
ldr r1, =0x0000AAAA
str r1, [r0, #MP1_6DRV_SR_OFFSET]
ldr r1, =0x0000AAAA
str r1, [r0, #MP1_7DRV_SR_OFFSET]
ldr r1, =0x00002AAA
str r1, [r0, #MP1_8DRV_SR_OFFSET]
// DMC0 initialization at single Type
ldr r0, =APB_DMC_0_BASE
ldr r1, =0x00101000 @PhyControl0 DLL parameter setting, manual 0x00101000
str r1, [r0, #DMC_PHYCONTROL0]
ldr r1, =0x00000086 @PhyControl1 DLL parameter setting, LPDDR/LPDDR2 Case
str r1, [r0, #DMC_PHYCONTROL1]
ldr r1, =0x00101002 @PhyControl0 DLL on
str r1, [r0, #DMC_PHYCONTROL0]
ldr r1, =0x00101003 @PhyControl0 DLL start
str r1, [r0, #DMC_PHYCONTROL0]
find_lock_val:
ldr r1, [r0, #DMC_PHYSTATUS] @Load Phystatus register value
and r2, r1, #0x7
cmp r2, #0x7 @Loop until DLL is locked
bne find_lock_val
and r1, #0x3fc0
mov r2, r1, LSL #18
orr r2, r2, #0x100000
orr r2 ,r2, #0x1000
orr r1, r2, #0x3 @Force Value locking
str r1, [r0, #DMC_PHYCONTROL0]
// setting DDR2
ldr r1, =0x0FFF2010 @ConControl auto refresh off
str r1, [r0, #DMC_CONCONTROL]
@MemControl BL=4, 1 chip, DDR2 type, dynamic self refresh, force precharge, dynamic power down off
ldr r1, =DMC0_MEMCONTROL
str r1, [r0, #DMC_MEMCONTROL]
@MemConfig0 256MB config, 8 banks,Mapping Method[12:15]0:linear, 1:linterleaved, 2:Mixed
ldr r1, =DMC0_MEMCONFIG_0
str r1, [r0, #DMC_MEMCONFIG0]
ldr r1, =DMC0_MEMCONFIG_1 @MemConfig1
str r1, [r0, #DMC_MEMCONFIG1]
ldr r1, =0xFF000000 @PrechConfig
str r1, [r0, #DMC_PRECHCONFIG]
@TimingAref 7.8us*133MHz=1038(0x40E), 100MHz=780(0x30C), 20MHz=156(0x9C), 10MHz=78(0x4E)
ldr r1, =DMC0_TIMINGA_REF
str r1, [r0, #DMC_TIMINGAREF]
ldr r1, =DMC0_TIMING_ROW @TimingRow for @200MHz
str r1, [r0, #DMC_TIMINGROW]
ldr r1, =DMC0_TIMING_DATA @TimingData CL=4
str r1, [r0, #DMC_TIMINGDATA]
ldr r1, =DMC0_TIMING_PWR @TimingPower
str r1, [r0, #DMC_TIMINGPOWER]
ldr r1, =0x07000000 @DirectCmd chip0 Deselect
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x01000000 @DirectCmd chip0 PALL
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x00020000 @DirectCmd chip0 EMRS2
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x00030000 @DirectCmd chip0 EMRS3
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x00010400 @DirectCmd chip0 EMRS1 (MEM DLL on, DQS# disable)
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x00000542 @DirectCmd chip0 MRS (MEM DLL reset) CL=4, BL=4
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x01000000 @DirectCmd chip0 PALL
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x05000000 @DirectCmd chip0 REFA
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x05000000 @DirectCmd chip0 REFA
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x00000442 @DirectCmd chip0 MRS (MEM DLL unreset)
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x00010780 @DirectCmd chip0 EMRS1 (OCD default)
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x00010400 @DirectCmd chip0 EMRS1 (OCD exit)
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x07100000 @DirectCmd chip1 Deselect
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x01100000 @DirectCmd chip1 PALL
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x00120000 @DirectCmd chip1 EMRS2
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x00130000 @DirectCmd chip1 EMRS3
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x00110400 @DirectCmd chip1 EMRS1 (MEM DLL on, DQS# disable)
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x00100542 @DirectCmd chip1 MRS (MEM DLL reset) CL=4, BL=4
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x01100000 @DirectCmd chip1 PALL
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x05100000 @DirectCmd chip1 REFA
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x05100000 @DirectCmd chip1 REFA
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x00100442 @DirectCmd chip1 MRS (MEM DLL unreset)
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x00110780 @DirectCmd chip1 EMRS1 (OCD default)
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x00110400 @DirectCmd chip1 EMRS1 (OCD exit)
str r1, [r0, #DMC_DIRECTCMD]
ldr r1, =0x0FF02030 @ConControl auto refresh on
str r1, [r0, #DMC_CONCONTROL]
ldr r1, =0xFFFF00FF @PwrdnConfig
str r1, [r0, #DMC_PWRDNCONFIG]
@MemControl BL=4, 1 chip, DDR2 type, dynamic self refresh, force precharge, dynamic power down off
ldr r1, =0x00202400
str r1, [r0, #DMC_MEMCONTROL]
mov pc, lr
=====================================================================
nand.c源码：
#define NFCONF (*(volatile unsigned int *)0xB0E00000)
#define NFCONT (*(volatile unsigned int *)0xB0E00004)
#define NFCMMD (*(volatile unsigned char *)0xB0E00008)
#define NFADDR (*(volatile unsigned char *)0xB0E0000C)
#define NFDATA (*(volatile unsigned char *)0xB0E00010)
#define NFSTAT (*(volatile unsigned int *)0xB0E00028)
#define MP0_3CON (*(volatile unsigned int *)0xE0200320)
#define MP0_1CON (*(volatile unsigned int *)0xE02002E0)
#define PAGE_SIZE 2048
#define NAND_SECTOR_SIZE_LP 2048
void wait_idle(void)
{
int i;
while(!(NFSTAT&(1<<0)));
for(i=0; i<10; i++);
}
void nand_select_chip(void)
{
int i;
NFCONT &= ~(1<<1);
for(i=0; i<10; i++);
}
void nand_deselect_chip(void)
{
NFCONT |= (1<<1);
}
void write_cmd(int cmd)
{
NFCMMD = cmd;
}
void write_addr(unsigned int addr)
{
int i;
NFADDR = (addr>>0) & 0xFF;
wait_idle();
NFADDR = (addr>>8) & 0x7;
wait_idle();
NFADDR = (addr>>11) & 0xFF;
wait_idle();
NFADDR = (addr>>19) & 0xFF;
wait_idle();
NFADDR = (addr>>27) & 0x1;
wait_idle();
}
unsigned char read_data(void)
{
return NFDATA;
}
static void nand_reset(void)
{
nand_select_chip();
write_cmd(0xff); // 复位命令
wait_idle();
nand_deselect_chip();
}
void nand_init(void)
{
// 设置时间参数(HCLK_PSYS = 667MHz/5 = 133MHz)
// TACLS[15:12]: TACLS = 1 1/133Mhz = 7.5ns
// TWRPH0[11:8]: TWRPH0 = 1 7.5ns * 2 = 15ns
// TWRPH1 [7:4]: TWRPH1 = 1 7.5ns * 2 = 15ns
// AddrCycle[1]: 1 = 指明地址周期为5次，这个是和2440的区别
NFCONF |= 1<<12 | 1<<8 | 1<<4;
NFCONF |= 1<<1;
// 使能NAND控制器
// 关闭片选信号
NFCONT |= (1<<0)|(1<<1);
// 设置相应管脚用于Nand Flash控制器
MP0_3CON = 0x22222222;
// 复位NAND Flash
nand_reset();
return;
}
// 读ID
void nand_read_id(char id[])
{
int i;
nand_select_chip();
write_cmd(0x90);
write_addr(0x00);
for (i = 0; i < 5; i++)
id[i] = read_data();
nand_deselect_chip();
}
// 读一页的函数
void nand_read(unsigned char *buf, unsigned long start_addr, int size)
{
int i, j;
// 选中芯片
nand_select_chip();
for(i=start_addr; i < (start_addr + size);)
{
// 发出READ0命令
write_cmd(0);
// Write Address
write_addr(i);
write_cmd(0x30);
wait_idle();
for(j=0; j < NAND_SECTOR_SIZE_LP; j++, i++)
{
*buf = read_data();
buf++;
}
}
// 取消片选信号
nand_deselect_chip();
}
void nand_write(int sdram_addr, int nand_addr, int size)
{
}
====================================================================
uart.c源码：
#define GPA0CON (*(volatile unsigned int *)0xE0200000)
#define ULCON0 (*(volatile unsigned int *)0xE2900000)
#define UCON0 (*(volatile unsigned int *)0xE2900004)
#define UTRSTAT0 (*(volatile unsigned int *)0xE2900010)
#define UTXH0 (*(volatile unsigned char *)0xE2900020)
#define URXH0 (*(volatile unsigned char *)0xE2900024)
#define UBRDIV0 (*(volatile unsigned int *)0xE2900028)
#define UDIVSLOT0 (*(volatile unsigned int *)0xE290002C)
void uart_init(void)
{
// 设置对应GPIO用于UART0
GPA0CON |= 0x22;
// 设置UART0寄存器
// bit[1:0]:0x3 = 8位数据位
// 其他位默认,即1位停止位，无校验，正常模式
ULCON0 |= (0x3<<0);
// Receive Mode [1:0]:1 = 接收采用查询或者中断模式
// Transmit Mode[3:2]:1 = 发送采用查询或者中断模式
// bit[6]:1 = 产生错误中断
// bit[10]:0 = 时钟源为PCLK
UCON0 = (1<<6)|(1<<2)|(1<<0);
// 设置波特率(详细信息请参考手册或者学习日记)
// DIV_VAL = UBRDIVn + (num of 1's in UDIVSLOTn)/16
// DIV_VAL = (PCLK / (bps x 16)) - 1
UBRDIV0 = 0x23;
UDIVSLOT0 = 0x808;
return;
}
char uart_getchar(void)
{
char c;
// 查询状态寄存器，直到有有效数据
while (!(UTRSTAT0 & (1<<0)));
c = URXH0; // 读取接收寄存器的值
return c;
}
void uart_putchar(char c)
{
// 查询状态寄存器，直到发送缓存为空
while (!(UTRSTAT0 & (1<<2)));
UTXH0 = c; // 写入发送寄存器
return;
}
=====================================================================
lcd.c源码：
#define GPF0CON (*(volatile unsigned int *)0xE0200120)
#define GPF1CON (*(volatile unsigned int *)0xE0200140)
#define GPF2CON (*(volatile unsigned int *)0xE0200160)
#define GPF3CON (*(volatile unsigned int *)0xE0200180)
#define GPD0CON (*(volatile unsigned int *)0xE02000A0)
#define GPD0DAT (*(volatile unsigned int *)0xE02000A4)
#define CLK_SRC1 (*(volatile unsigned int *)0xe0100204)
#define CLK_DIV1 (*(volatile unsigned int *)0xe0100304)
#define DISPLAY_CONTROL (*(volatile unsigned int *)0xe0107008)
#define VIDCON0 (*(volatile unsigned int *)0xF8000000)
#define VIDCON1 (*(volatile unsigned int *)0xF8000004)
#define VIDTCON2 (*(volatile unsigned int *)0xF8000018)
#define VIDTCON3 (*(volatile unsigned int *)0xF800001c)
#define WINCON0 (*(volatile unsigned int *)0xF8000020)
#define WINCON2 (*(volatile unsigned int *)0xF8000028)
#define SHADOWCON (*(volatile unsigned int *)0xF8000034)
#define VIDOSD0A (*(volatile unsigned int *)0xF8000040)
#define VIDOSD0B (*(volatile unsigned int *)0xF8000044)
#define VIDOSD0C (*(volatile unsigned int *)0xF8000048)
#define VIDW00ADD0B0 (*(volatile unsigned int *)0xF80000A0)
#define VIDW00ADD1B0 (*(volatile unsigned int *)0xF80000D0)
#define VIDW00ADD2 (*(volatile unsigned int *)0xF8000100)
#define VIDTCON0 (*(volatile unsigned int *)0xF8000010)
#define VIDTCON1 (*(volatile unsigned int *)0xF8000014)
#define VSPW 9
#define VBPD 13
#define LINEVAL 479
#define VFPD 21
#define HSPW 19
#define HBPD 25
#define HOZVAL 799
#define HFPD 209
#define LeftTopX 0
#define LeftTopY 0
#define RightBotX 799
#define RightBotY 479
#define FRAME_BUFFER (0x3f000000)
void lcd_init(void)
{
// 1. 设置相关GPIO引脚用于LCD
GPF0CON = 0x22222222; // GPF0[7:0]
GPF1CON = 0x22222222; // GPF1[7:0]
GPF2CON = 0x22222222; // GPF2[7:0]
GPF3CON = 0x22222222; // GPF3[7:0]
// 使能LCD本身
GPD0CON |= 1<<4;
GPD0DAT |= 1<<1;
// 该寄存器是时钟相关
// Display path selection
// 10: RGB=FIMD I80=FIMD ITU=FIMD
DISPLAY_CONTROL = 2<<0;
// 2. 初始化210的display controller
// 2.1 hsync,vsync,vclk,vden的极性和时间参数
// 2.2 行数、列数(分辨率),象素颜色的格式
// 2.3 分配显存(frame buffer),写入display controller
// CLKVAL_F[13:6]:该值需要根据LCD手册做相应的修改
// HCLKD=166.75MHz，DCLK(min) = 20ns(50MHz)
// VCLK = 166.75 / (5+1) = 28MHz
// CLKDIR [4]:1 = Divided by CLKVAL_F
// ENVID [1]:1 = Enable the video output and the Display control signal.
// ENVID_F [0]:1 = Enable the video output and the Display control signal.
VIDCON0 &= ~((3<<26) | (1<<18) | (0xff<<6) | (1<<2)); // RGB I/F, RGB Parallel format,
VIDCON0 |= ((5<<6) | (1<<4) );
// 设置极性(该值需要根据LCD手册做相应的修改)
// IVDEN [4]:0 = Normal
// IVSYNC[5]:1 = Inverted
// IHSYNC[6]:1 = Inverted
// IVCLK [7]:0 = Video data is fetched at VCLK falling edge
VIDCON1 &= ~(1<<7); // 在vclk的下降沿获取数据
VIDCON1 |= ((1<<6) | (1<<5)); // HSYNC极性反转, VSYNC极性反转
// 设置时序(需要修改)
VIDTCON0 = (VBPD << 16) | (VFPD << 8) | (VSPW << 0);
VIDTCON1 = (HBPD << 16) | (HFPD << 8) | (HSPW << 0);
// 设置屏幕的大小
// LINEVAL[21:11]:多少行 = 480
// HOZVAL [10:0] :水平大小 = 800
VIDTCON2 = (LINEVAL << 11) | (HOZVAL << 0);
// WSWP_F [15] :1 = Swap Enable(为什么要使能)，很关键的一位，能够解决掉重影问题
// BPPMODE_F[5:2]:1011 = unpacked 24 BPP (non-palletized R:8-G:8-B:8 )
// ENWIN_F [0]: 1 = Enable the video output and the VIDEO control signal.
WINCON0 &= ~(0xf << 2);
WINCON0 |= (0xB<<2)|(1<<15);
// 窗口0，左上角的位置(0,0)
// 窗口0，右下角的位置(800,480)
VIDOSD0A = (LeftTopX<<11) | (LeftTopY << 0);
VIDOSD0B = (RightBotX<<11) | (RightBotY << 0);
// 大小
VIDOSD0C = (LINEVAL + 1) * (HOZVAL + 1);
VIDW00ADD0B0 = FRAME_BUFFER;
// VBASEL = VBASEU + (LINEWIDTH+OFFSIZE) x (LINEVAL+1)
// = 0 + (800*4 + 0) * 479
// =
VIDW00ADD1B0 = (((HOZVAL + 1)*4 + 0) * (LINEVAL + 1)) & (0xffffff);
//VIDW00ADD1B0 = FRAME_BUFFER + HOZVAL * LINEVAL * 4; // 新加的，是该这个吗?
SHADOWCON = 0x1; // 使能通道0
// LCD控制器开启
VIDCON0 |= 0x3; // 开启总控制器
WINCON0 |= 1; // 开启窗口0
}
void lcd_draw_pixel(int row, int col, int color)
{
int * pixel = (int *)FRAME_BUFFER;
*(pixel + row * (HOZVAL+1) + col) = color;
return;
}
void lcd_clear_screen(int color)
{
int i, j;
for (i = 0; i < (LINEVAL+1); i++)
for (j = 0; j < (HOZVAL+1); j++)
{
lcd_draw_pixel(i, j, color);
}
return;
}
void lcd_draw_bmp(int bmp_file_addr)
{
int i, j;
char * p = (char *)bmp_file_addr;
int blue, green, red;
int color;
// read bmp file
// bmp file header is 54 bytes
p += 54;
for (i = 0; i < 480; i++)
for (j = 0; j < 800; j++)
{
blue = *p++;
green = *p++;
red = *p++;
color = red << 16 | green << 8 | blue << 0;
lcd_draw_pixel(480-i, j, color);
}
return;
}
====================================================================
lib.c源码：
#include "uart.h"
#define UTRSTAT0 (*(volatile unsigned int *)0xE2900010)
#define UTXH0 (*(volatile unsigned char *)0xE2900020)
#define URXH0 (*(volatile unsigned char *)0xE2900024)
void delay(void)
{
volatile int i = 0x100000;
while (i--);
}
void putchar_hex(char c)
{
char * hex = "0123456789ABCDEF";
uart_putchar(hex[(c>>4) & 0x0F]);
uart_putchar(hex[(c>>0) & 0x0F]);
return;
}
int putchar(int c)
{
if(c == '\r')
{
while(!(UTRSTAT0&(1<<1)));
UTXH0 = '\n';
}
if(c == '\n')
{
while(!(UTRSTAT0&(1<<1)));
UTXH0 = '\r';
}
while(!(UTRSTAT0&(1<<1)));
UTXH0 = c;
}
int getchar(void)
{
int c;
c = (int)uart_getchar();
if (c == '\r')
return '\n';
return c;
}
int puts(const char * s)
{
while (*s)
putchar(*s++);
return 0;
}
char * gets(char * s)
{
char * p = s;
while ((*p = getchar()) != '\n')
{
if (*p != '\b')
putchar(*p++);
else
{
if (p > s)
{
puts ("\b \b");
p--;
}
}
}
*p = '\0';
putchar('\n');
return s;
}
void putint_hex(int a)
{
putchar_hex( (a>>24) & 0xFF );
putchar_hex( (a>>16) & 0xFF );
putchar_hex( (a>>8) & 0xFF );
putchar_hex( (a>>0) & 0xFF );
}
char * itoa(int a, char * buf)
{
int num = a;
int i = 0;
int len = 0;
do
{
buf[i++] = num % 10 + '0';
num /= 10;
} while (num);
buf[i] = '\0';
len = i;
for (i = 0; i < len/2; i++)
{
char tmp;
tmp = buf[i];
buf[i] = buf[len-i-1];
buf[len-i-1] = tmp;
}
return buf;
}
int strcmp(const char * s1, const char * s2)
{
while (*s1 == *s2)
{
if (*s1 == '\0')
return 0;
s1++;
s2++;
}
return *s1 - *s2;
}
int atoi(char * buf)
{
int value = 0;
int base = 10;
int i = 0;
if (buf[0] == '0' && buf[1] == 'x')
{
base = 16;
i = 2;
}
// 123 = (1 * 10 + 2) * 10 + 3
// 0x1F = 1 * 16 + F(15)
while (buf[i])
{
int tmp;
if (buf[i] <= '9' && buf[i] >= '0')
tmp = buf[i] - '0';
else
tmp = buf[i] - 'a' + 10;
value = value * base + tmp;
i++;
}
return value;
}
typedef int * va_list;
#define va_start(ap, A) (ap = (int *)&(A) + 1)
#define va_arg(ap, T) (*(T *)ap++)
#define va_end(ap) ((void)0)
int wy_printf(const char * format, ...)
{
char c;
va_list ap;
va_start(ap, format);
while ((c = *format++) != '\0')
{
switch (c)
{
case '%':
c = *format++;
switch (c)
{
char ch;
char * p;
int a;
char buf[100];
case 'c':
ch = va_arg(ap, int);
putchar(ch);
break;
case 's':
p = va_arg(ap, char *);
puts(p);
break;
case 'x':
a = va_arg(ap, int);
putint_hex(a);
break;
case 'd':
a = va_arg(ap, int);
itoa(a, buf);
puts(buf);
break;
default:
break;
}
break;
default:
putchar(c);
break;
}
}
return 0;
}
====================================================================
timer.c源码：
#include "lib.h"
#define GPD0CON (*(volatile unsigned int *)0xE02000A0)
#define TCFG0 (*(volatile unsigned int *)0xE2500000)
#define TCFG1 (*(volatile unsigned int *)0xE2500004)
#define TCON (*(volatile unsigned int *)0xE2500008)
#define TCNTB0 (*(volatile unsigned int *)0xE250000C)
#define TCMPB0 (*(volatile unsigned int *)0xE2500010)
#define TCNTO0 (*(volatile unsigned int *)0xE2500014)
void pwm_init(void)
{
// 配置为GPD0_0用于PWM输出
GPD0CON |= (0x2 << 0); // TOUT_0
}
void timer0_init(void)
{
// 设置时钟源
// Timer0 input clock Frequency = 66700000 / ( {prescaler + 1} ) / {divider value}
// = 66700000 / (1+1) / 1
// = 33350000( 即1s计数33350000次 )
TCFG0 &= ~(0xff);
TCFG0 |= 1; // Prescaler = 1
TCFG1 &= ~0xf; // 0000 = 1/1
// 设置TCNTB0(即PWM的频率)
TCNTB0 = 33350; // PWM的频率为1KHz
// 设置TCMPB0(即PWM的占空比)
TCMPB0 = 16675; // 占空比为50%
TCON &= ~(1<<2); // 不进行电平反转(即引脚初始值为0)
TCON |= (1<<3); // auto-reload
}
void pwm_start(void)
{
TCON |= (1<<1); // set manual update
TCON |= (1<<0); // start timer 0
TCON &= ~(1<<1); // clean manual update
}
void pwm_stop(void)
{
TCON &= ~(1<<0); // stop timer 0
}
===================================================================
command.c源码：
#include "lib.h"
#include "nand.h"
#include "setup.h"
extern void (*fp)(int, int, int);
int help(int argc, char * argv[])
{
wy_printf("do_command 《%s》 \n", argv[0]);//实际为“<”
wy_printf("help message: \n");
wy_printf("md - memory dispaly\n");
wy_printf("mw - memory write\n");
wy_printf("nand read - nand read sdram_addr nand_addr size\n");
wy_printf("nand write - nand write sdram_addr nand_addr size\n");
wy_printf("bootm - boot zImage\n");
return 0;
}
int md(int argc, char * argv[])
{
unsigned long *p = (unsigned long *)0;
int i, j;
wy_printf("do_command 《%s》 \n", argv[0]);
if (argc <= 1) {
wy_printf ("Usage:\n%s\n", "md address");
return 1;
}
if (argc >= 2)
p = (unsigned long *)atoi(argv[1]);
for (j = 0; j < 16; j++)
{
wy_printf("%x: ", p);
for (i = 0; i < 4; i++)
wy_printf("%x ", *p++);
wy_printf("\n");
}
return 0;
}
int mw(int argc, char * argv[])
{
unsigned long *p = (unsigned long *)0;
int v = 0;
wy_printf("do_command 《%s》 \n", argv[0]);//实际为“<”
if (argc <= 2) {
wy_printf ("Usage:\n%s\n", "md address data");
return 1;
}
if (argc >= 2)
p = (unsigned long *)atoi(argv[1]);
if (argc >= 3)
v = atoi(argv[2]);
*p = v;
return 0;
}
int nand(int argc, char *argv[])
{
int nand_addr, sdram_addr;
unsigned int size;
if (argc < 5)
{
wy_printf("nand read sdram_addr nand_addr size\n");
wy_printf("nand write sdram_addr nand_addr size\n");
return 0;
}
sdram_addr = atoi(argv[2]);
nand_addr = atoi(argv[3]);
size = atoi(argv[4]);
wy_printf("do_command 《%s》 \n", argv[0]); //实际为“<”
wy_printf("sdram 0x%x, nand 0x%x, size 0x%x\n", sdram_addr, nand_addr, size);
if (strcmp(argv[1], "read") == 0)
nand_read((unsigned char *)sdram_addr, nand_addr, size);
if (strcmp(argv[1], "write") == 0)
nand_write(sdram_addr, nand_addr, size);
wy_printf("nand %s finished!\n", argv[1]);
return 0;
}
int bootm(int argc, char * argv[])
{
wy_printf("loading linux from 0x400000 to 0x20008000...\n");
nand_read(0x20008000, 0x400000, 0x800000);
wy_printf("boot linux ...\n");
fp(0, 2456, 0x20000100);
return 0;
}
void run_command(int argc, char * argv[])
{
if (strcmp(argv[0], "help") == 0)
{
help(argc, argv);
return;
}
if (strcmp(argv[0], "md") == 0)
{
md(argc, argv);
return;
}
if (strcmp(argv[0], "mw") == 0)
{
mw(argc, argv);
return;
}
if (strcmp(argv[0], "bootm") == 0)
{
bootm(argc, argv);
return;
}
if (strcmp(argv[0], "nand") == 0)
nand(argc, argv);
if(argc >= 1)
wy_printf("Unknown command '%s' - try 'help' \n",argv[0]);
return;
}
===================================================================
main.c源码：
#include "command.h"
#include "clock.h"
#include "led.h"
#include "uart.h"
#include "lib.h"
#include "nand.h"
#include "lcd.h"
#include "timer.h"
#include "setup.h"
#define UTRSTAT0 (*(volatile unsigned int *)0xE2900010)
#define CFG_PROMPT "WY_BOOT # " // Monitor Command Prompt
#define CFG_CBSIZE 256 // Console I/O Buffer Size
#define BOOTDELAY 5 // 倒计时
void (*fp)(int, int, int);
char *argv[10];
int readline (const char *const prompt)
{
char console_buffer[CFG_CBSIZE]; // console I/O buffer
char *buf = console_buffer;
int argc = 0;
int state = 0;
//puts(prompt);
wy_printf("%s",prompt);
gets(console_buffer);
while (*buf)
{
if (*buf != ' ' && state == 0)
{
argv[argc++] = buf;
state = 1;
}
if (*buf == ' ' && state == 1)
{
*buf = '\0';
state = 0;
}
buf++;
}
return argc;
}
void message(void)
{
wy_printf("\nThis bootloader support some command to test peripheral:\n");
wy_printf("Such as: LCD, IIS, BUZZER \n");
wy_printf("Try 'help' to learn them \n\n");
}
const char cmd[] = "root=/dev/nfs nfsroot=192.168.1.104:/work/nfs_root/wy_fs ip=192.168.1.17 console=ttySAC0";
void init_tag(int addr)
{
struct tag * p;
int i;
p = (struct tag*) addr;
p->hdr.tag = ATAG_CORE;
p->hdr.size = tag_size(tag_core);
p->u.core.flags = 0;
p->u.core.pagesize = 0;
p->u.core.rootdev = 0;
p = tag_next(p);
p->hdr.tag = ATAG_CMDLINE;
p->hdr.size = (sizeof (cmd) + sizeof(struct tag_header) + 3) >>2;
for(i=0; i< sizeof (cmd); i++)
p->u.cmdline.cmdline[i] = cmd[i];
p = tag_next(p);
p->hdr.tag = ATAG_MEM;
p->hdr.size = tag_size(tag_mem32);
p->u.mem.size = 512*1024*1024;
p->u.mem.start = 0x20000000;
p = tag_next(p);
p->hdr.tag = ATAG_NONE;
p->hdr.size = 0;
}
void init_boot_parameter(void)
{
int addr = 0x20008000;
int taglist_mem_address = 0x20000100;
fp = (void (*)(int, int, int))addr;
init_tag(taglist_mem_address);
}
int tstc (void)
{
return UTRSTAT0 & 0x1;
}
void autoboot(void)
{
int i;
char bootdelay = BOOTDELAY;
while(1)
{
wy_printf("Hit any key to stop autoboot: %d \n", bootdelay);
if(bootdelay == 0)
{
wy_printf("loading linux from 0x400000 to 0x20008000...\n");
nand_read(0x20008000, 0x400000, 0x800000);
wy_printf("boot linux ...\n");
fp(0, 2456, 0x20000100);
return;
}
for(i=0;i<=8;i++)
{
delay();
if( tstc() )
return;
}
bootdelay--;
}
return;
}
int main(void)
{
char buf[6];
int argc = 0;
int i = 0;
led_init(); // 设置对应管脚为输出
uart_init(); // 初始化UART0
lcd_init(); // 初始化LCD
nand_read_id(buf);
timer0_init(); // 初始化定时器0，用于PWM输出
init_boot_parameter(); // 初始化启动内核需要的相关类容
wy_printf("\nloading logo from NAND 0xc00000 to DDR 0x3fc00000...");
nand_read((unsigned char *)0x3fc00000, 0xC00000, 0x300000);
wy_printf("\n**********************************************************\n");
wy_printf(" wy_bootloader\n");
wy_printf(" vars: %d \n",2012);
wy_printf(" nand id:");
putchar_hex(buf[0]);
putchar_hex(buf[1]);
putchar_hex(buf[2]);
putchar_hex(buf[3]);
putchar_hex(buf[4]);
wy_printf("\n**********************************************************\n");
lcd_draw_bmp(0x3fc00000); // 显示LOGO
autoboot(); // 延时自启动
while (1)
{
argc = readline (CFG_PROMPT);
if(argc == 0 && i ==0)
{
message();
i=1;
}
run_command(argc, argv);
}
return 0;
}
=====================================================================
Makefile文件：
uart.bin:start.s main.c uart.c clock.c led.c lib.c command.c nand.c mem_setup.S lcd.c timer.c
arm-linux-gcc -nostdlib -c start.s -o start.o
arm-linux-gcc -nostdlib -c main.c -o main.o
arm-linux-gcc -nostdlib -c uart.c -o uart.o
arm-linux-gcc -nostdlib -c lib.c -o lib.o
arm-linux-gcc -nostdlib -c clock.c -o clock.o
arm-linux-gcc -nostdlib -c led.c -o led.o
arm-linux-gcc -nostdlib -c command.c -o command.o
arm-linux-gcc -nostdlib -c nand.c -o nand.o
arm-linux-gcc -nostdlib -c lcd.c -o lcd.o
arm-linux-gcc -nostdlib -c mem_setup.S -o mem_setup.o
arm-linux-gcc -nostdlib -c timer.c -o timer.o
arm-linux-ld -T bootloader.lds start.o main.o uart.o lib.o clock.o led.o command.o nand.o mem_setup.o lcd.o timer.o -o uart_elf
arm-linux-objcopy -O binary -S uart_elf uart.bin
clean:
rm -rf *.o *.bin uart_elf *.dis
=====================================================================
bootloader.lds链接文件：
SECTIONS {
. = 0x36000010;
.text : {
* (.text)
}
. = ALIGN(4);
.rodata : {
* (.rodata)
}
. = ALIGN(4);
.data : {
* (.data)
}
. = ALIGN(4);
bss_start = .;
.bss : { *(.bss) *(COMMON) }
bss_end = .;
}
==================================================================
倒计时自启动内核：
用官方的u-boot的时候，总是有倒计时启动内核，感觉特别的爽，因此，我得给自己写的bootloader加上该功能(方法比较粗糙)。
这部分代码没有任何难道，大家一看代码就能够明白，添加类容如下：
void autoboot(void)
{
int i;
char bootdelay = BOOTDELAY;
while(1)
{
wy_printf("Hit any key to stop autoboot: %d \n", bootdelay);
if(bootdelay == 0)
{
wy_printf("loading linux from 0x400000 to 0x20008000...\n");
nand_read(0x20008000, 0x400000, 0x800000);
wy_printf("boot linux ...\n");
fp(0, 2456, 0x20000100);
return;
}
for(i=0;i<=8;i++)
{
delay();
if( tstc() ) // 这个函数只是去读UART的状态而已
return;
}
bootdelay--;
}
return;
}
该部分代码放在了"Tiny210学习日记_代码"目录下了，名为"bootloader_bootdelay"。
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图为直接耦合共射放大电路~ 直流通路里有直流电源Vcc，可是交流通路里没有Vcc啊，负载线方程怎么会相同呢？ 请最好把Uce和Ic的函数关系式即负载线方程写出来~… 查看全部问答＞ |
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