S5pc100裸板全攻略之SPI

作者：赵孝强,华清远见嵌入式培训中心讲师。
以下是s5pc100的不带系统SPI 操作m25p10的程序，需要map.lds,Makefile,s5pc100,文件，用v7交叉工具链，以上文件可在www.farsight.com.cn下载到。
#include "s5pc100.h"

#include "s5pc100.h"

#include "uart.h"

#define SPI0_CLK_GATE_ON (1<<6)

#define MAX 50

/* Flash opcodes. */

#define OPCODE_WREN 0x06 /* Write enable */

#define OPCODE_WRDA 0x04 /* Write disable */

#define OPCODE_RDSR 0x05 /* Read status register */

#define OPCODE_WRSR 0x01 /* Write status register 1 byte */

#define OPCODE_NORM_READ 0x03 /* Read data bytes (low frequency) */

#define OPCODE_FAST_READ 0x0b /* Read data bytes (high frequency) */

#define OPCODE_PP 0x02 /* Page Program (up to 256 bytes) */

#define OPCODE_BE_4K 0x20 /* Erase 4KiB block */

#define OPCODE_BE_32K 0x52 /* Erase 32KiB block */

#define OPCODE_CHIP_ERASE 0xc7 /* Erase whole flash chip */

#define OPCODE_SE 0xd8 /* Sector erase (usually 64KiB) */

#define OPCODE_RDID 0x9f /* Read JEDEC ID */

/* Status Register bits. */

#define SR_WIP 1 /* Write in progress */

#define SR_WEL 2 /* Write enable latch */

extern void printf(const char *fmt, ...);

void cfg_gpio(void)

{

/* set GPB[0~3] to support spi0*/

GPB.GPBCON = (GPB.GPBCON & 0xffff0000) | 0x2222;

}

void set_clk(void)

{

/* enable clk_gate, spi_clksel = PCLK; spi_scaler = 0 */

CLK_GATE_D1.CLK_GATE_D1_4 |= SPI0_CLK_GATE_ON;

SPI0.CLKCFG &= 0x0;

}

void delay(int times)

{

volatile int i,j;

for (j = 0; j < times; j++){

for (i = 0; i < 100000; i++);

i = i + 1;}

}

void disable_chip(void)

{

/* disable chip*/

SPI0.SLAVESEL |= 0x1;

delay(1);

}

void enable_chip(void)

{

/* enable chip*/

SPI0.SLAVESEL &= ~0x1;

delay(1);

}

void soft_reset(void)

{

SPI0.CHCFG |= 0x1 << 5;

delay(1);

SPI0.CHCFG &= ~(0x1 << 5);

}

void cfg_spi0(void)

{

soft_reset();

SPI0.CHCFG &= ~((0x1 << 4) | (0x1 << 3) | (0x1 << 2));

SPI0.CHCFG &= ~0x3;

SPI0.MODECFG = (SPI0.MODECFG & ~((0x3 << 17) | (0x3 << 29))) | (0x0 << 17) | (0x0 << 29);

SPI0.SLAVESEL &= ~(0x1 << 1);

SPI0.CLKCFG |= 1 << 8;

}

void transfer(unsigned char *data, int len)

{

int i;

SPI0.CHCFG &= ~(0x1 << 1);

SPI0.CHCFG = SPI0.CHCFG | 0x1; // enable Tx and disable Rx

delay(1);

for (i = 0; i < len; i++){

SPI0.TXDATA = data[i];

while( !(SPI0.STATUS & (0x1 << 21)) );

delay(1); }

SPI0.CHCFG &= ~0x1;

}

void receive(unsigned char *buf, int len)

{

int i;

SPI0.CHCFG &= ~0x1; // disable Tx

SPI0.CHCFG |= 0x1 << 1; // enable Rx

delay(1);

for (i = 0; i < len; i++){

buf[i] = SPI0.RXDATA;

delay(1); }

SPI0.CHCFG &= ~(0x1 << 1);

}

void read_ID(void)

{

unsigned char buf[3];

int i;

buf[0] = OPCODE_RDID;

soft_reset();

enable_chip();

transfer(buf, 1);

receive(buf, 3);

disable_chip();

printf("MI = %x\tMT = %x\tMC = %x\t\n", buf[0], buf[1], buf[2]);

}

void erase_sector(int addr)

{

unsigned char buf[4];

buf[0] = OPCODE_SE;

buf[1] = addr >> 16;

buf[2] = addr >> 8;

buf[3] = addr;

enable_chip();

transfer(buf, 4);

disable_chip();

}

void erase_chip()

{

unsigned char buf[4];

buf[0] = OPCODE_CHIP_ERASE;

enable_chip();

transfer(buf, 1);

disable_chip();

}

void wait_till_write_finished()

{

unsigned char buf[1];

enable_chip();

buf[0] = OPCODE_RDSR;

transfer(buf, 1);

while(1) {

receive(buf, 1);

if(buf[0] & SR_WIP) {

// printf( "Write is still in progress\n" ); }

else {

printf( "Write is finished.\n" );

break;

}

}

disable_chip();

}

void enable_write()

{

unsigned char buf[1];

buf[0] = OPCODE_WREN;

enable_chip();

transfer(buf, 1);

disable_chip();

}

void write_spi(unsigned char *data, int len, int addr)

{

unsigned char buf[4];

//cfg_spi0();

soft_reset();

enable_write();

/* */

erase_chip();

wait_till_write_finished();

buf[0] = OPCODE_PP;

buf[1] = addr >> 16;

buf[2] = addr >> 8;

buf[3] = addr;

//cfg_spi0();

soft_reset();

enable_write();

enable_chip();

transfer(buf, 4);

transfer(data, len);

disable_chip();

wait_till_write_finished();

}

void read_spi(unsigned char *data, int len, int addr)

{

unsigned char buf[4];

//cfg_spi0();

soft_reset();

buf[0] = OPCODE_NORM_READ;

buf[1] = addr >> 16;

buf[2] = addr >> 8;

buf[3] = addr;

enable_chip();

transfer(buf, 4);

receive(data, len);

disable_chip();

}

int main()

{

unsigned char buf[10] = "home\n";

unsigned char data[10] = "morning\n";

uart0_init();

printf("aaaaa \n");

/* initialize spi0 */

cfg_gpio();

set_clk();

cfg_spi0();

while(1)

{

read_ID();

write_spi(buf, 4, 0);

read_spi(data, 4, 0);

printf("read from spi :%s", data);

}

return 0;

}
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