puts.c

来自「优龙2410linux2.6.8内核源代码」· C语言 代码 · 共 139 行

/*
 * Debug routines which directly access the uart.
 */

#include <linux/types.h>
#include <asm/gt64120.h>


//#define SERIAL_BASE    EV96100_UART0_REGS_BASE
#define SERIAL_BASE    0xBD000020
#define NS16550_BASE   SERIAL_BASE

#define SERA_CMD       0x0D
#define SERA_DATA      0x08
//#define SERB_CMD       0x05
#define SERB_CMD       20
#define SERB_DATA      0x00
#define TX_BUSY        0x20

#define TIMEOUT    0xffff
#undef SLOW_DOWN

static const char digits[16] = "0123456789abcdef";
static volatile unsigned char *const com1 = (unsigned char *) SERIAL_BASE;


#ifdef SLOW_DOWN
static inline void slow_down()
{
	int k;
	for (k = 0; k < 10000; k++);
}
#else
#define slow_down()
#endif

void putch(const unsigned char c)
{
	unsigned char ch;
	int i = 0;

	do {
		ch = com1[SERB_CMD];
		slow_down();
		i++;
		if (i > TIMEOUT) {
			break;
		}
	} while (0 == (ch & TX_BUSY));
	com1[SERB_DATA] = c;
}

void putchar(const unsigned char c)
{
	unsigned char ch;
	int i = 0;

	do {
		ch = com1[SERB_CMD];
		slow_down();
		i++;
		if (i > TIMEOUT) {
			break;
		}
	} while (0 == (ch & TX_BUSY));
	com1[SERB_DATA] = c;
}

void puts(unsigned char *cp)
{
	unsigned char ch;
	int i = 0;

	while (*cp) {
		do {
			ch = com1[SERB_CMD];
			slow_down();
			i++;
			if (i > TIMEOUT) {
				break;
			}
		} while (0 == (ch & TX_BUSY));
		com1[SERB_DATA] = *cp++;
	}
	putch('\r');
	putch('\n');
}

void fputs(unsigned char *cp)
{
	unsigned char ch;
	int i = 0;

	while (*cp) {

		do {
			ch = com1[SERB_CMD];
			slow_down();
			i++;
			if (i > TIMEOUT) {
				break;
			}
		} while (0 == (ch & TX_BUSY));
		com1[SERB_DATA] = *cp++;
	}
}


void put64(uint64_t ul)
{
	int cnt;
	unsigned ch;

	cnt = 16;		/* 16 nibbles in a 64 bit long */
	putch('0');
	putch('x');
	do {
		cnt--;
		ch = (unsigned char) (ul >> cnt * 4) & 0x0F;
		putch(digits[ch]);
	} while (cnt > 0);
}

void put32(unsigned u)
{
	int cnt;
	unsigned ch;

	cnt = 8;		/* 8 nibbles in a 32 bit long */
	putch('0');
	putch('x');
	do {
		cnt--;
		ch = (unsigned char) (u >> cnt * 4) & 0x0F;
		putch(digits[ch]);
	} while (cnt > 0);
}