serial.c

linux下的BOOT程序原码,有需要的可以来下,保证好用

	clk = gd->cpu_clk;
	tmp = CFG_BASE_BAUD * 16;
	udiv = (clk + tmp / 2) / tmp;
	if (udiv > UDIV_MAX)                    /* max. n bits for udiv */
		udiv = UDIV_MAX;
	reg |= (udiv) << UCR0_UDIV_POS;	        /* set the UART divisor */
	reg |= (udiv) << UCR1_UDIV_POS;	        /* set the UART divisor */
	mtdcr (cpc0_ucr, reg);
#else /* CONFIG_405EP */
	reg = mfdcr(cntrl0) & ~CR0_MASK;
#ifdef CFG_EXT_SERIAL_CLOCK
	clk = CFG_EXT_SERIAL_CLOCK;
	udiv = 1;
	reg |= CR0_EXTCLK_ENA;
#else
	clk = gd->cpu_clk;
#ifdef CFG_405_UART_ERRATA_59
	udiv = 31;			/* Errata 59: stuck at 31 */
#else
	tmp = CFG_BASE_BAUD * 16;
	udiv = (clk + tmp / 2) / tmp;
	if (udiv > UDIV_MAX)                    /* max. n bits for udiv */
		udiv = UDIV_MAX;
#endif
#endif
	reg |= (udiv - 1) << CR0_UDIV_POS;	/* set the UART divisor */
	mtdcr (cntrl0, reg);
#endif /* CONFIG_405EP */

	tmp = gd->baudrate * udiv * 16;
	bdiv = (clk + tmp / 2) / tmp;

#if defined(CONFIG_SERIAL_MULTI)
	out8 (dev_base + UART_LCR, 0x80);	/* set DLAB bit */
	out8 (dev_base + UART_DLL, bdiv);	/* set baudrate divisor */
	out8 (dev_base + UART_DLM, bdiv >> 8);/* set baudrate divisor */
	out8 (dev_base + UART_LCR, 0x03);	/* clear DLAB; set 8 bits, no parity */
	out8 (dev_base + UART_FCR, 0x00);	/* disable FIFO */
	out8 (dev_base + UART_MCR, 0x00);	/* no modem control DTR RTS */
	val = in8 (dev_base + UART_LSR);	/* clear line status */
	val = in8 (dev_base + UART_RBR);	/* read receive buffer */
	out8 (dev_base + UART_SCR, 0x00);	/* set scratchpad */
	out8 (dev_base + UART_IER, 0x00);	/* set interrupt enable reg */
#else
	out8 (ACTING_UART0_BASE + UART_LCR, 0x80);	/* set DLAB bit */
	out8 (ACTING_UART0_BASE + UART_DLL, bdiv);	/* set baudrate divisor */
	out8 (ACTING_UART0_BASE + UART_DLM, bdiv >> 8);/* set baudrate divisor */
	out8 (ACTING_UART0_BASE + UART_LCR, 0x03);	/* clear DLAB; set 8 bits, no parity */
	out8 (ACTING_UART0_BASE + UART_FCR, 0x00);	/* disable FIFO */
	out8 (ACTING_UART0_BASE + UART_MCR, 0x00);	/* no modem control DTR RTS */
	val = in8 (ACTING_UART0_BASE + UART_LSR);	/* clear line status */
	val = in8 (ACTING_UART0_BASE + UART_RBR);	/* read receive buffer */
	out8 (ACTING_UART0_BASE + UART_SCR, 0x00);	/* set scratchpad */
	out8 (ACTING_UART0_BASE + UART_IER, 0x00);	/* set interrupt enable reg */
#endif
	return (0);
}

#endif /* if defined(CONFIG_440) */

#if defined(CONFIG_SERIAL_MULTI)
void serial_setbrg_dev (unsigned long dev_base)
#else
void serial_setbrg (void)
#endif
{
	DECLARE_GLOBAL_DATA_PTR;

	unsigned long tmp;
	unsigned long clk;
	unsigned long udiv;
	unsigned short bdiv;

#ifdef CFG_EXT_SERIAL_CLOCK
	clk = CFG_EXT_SERIAL_CLOCK;
#else
	clk = gd->cpu_clk;
#endif

#ifdef CONFIG_405EP
	udiv = ((mfdcr (cpc0_ucr) & UCR0_MASK) >> UCR0_UDIV_POS);
#else
	udiv = ((mfdcr (cntrl0) & 0x3e) >> 1) + 1;
#endif /* CONFIG_405EP */
	tmp = gd->baudrate * udiv * 16;
	bdiv = (clk + tmp / 2) / tmp;

#if defined(CONFIG_SERIAL_MULTI)
	out8 (dev_base + UART_LCR, 0x80);	/* set DLAB bit */
	out8 (dev_base + UART_DLL, bdiv);	/* set baudrate divisor */
	out8 (dev_base + UART_DLM, bdiv >> 8);/* set baudrate divisor */
	out8 (dev_base + UART_LCR, 0x03);	/* clear DLAB; set 8 bits, no parity */
#else
	out8 (ACTING_UART0_BASE + UART_LCR, 0x80);	/* set DLAB bit */
	out8 (ACTING_UART0_BASE + UART_DLL, bdiv);	/* set baudrate divisor */
	out8 (ACTING_UART0_BASE + UART_DLM, bdiv >> 8);/* set baudrate divisor */
	out8 (ACTING_UART0_BASE + UART_LCR, 0x03);	/* clear DLAB; set 8 bits, no parity */
#endif
}

#if defined(CONFIG_SERIAL_MULTI)
void serial_putc_dev (unsigned long dev_base, const char c)
#else
void serial_putc (const char c)
#endif
{
	int i;

	if (c == '\n')
#if defined(CONFIG_SERIAL_MULTI)
		serial_putc_dev (dev_base, '\r');
#else
		serial_putc ('\r');
#endif

	/* check THRE bit, wait for transmiter available */
	for (i = 1; i < 3500; i++) {
#if defined(CONFIG_SERIAL_MULTI)
		if ((in8 (dev_base + UART_LSR) & 0x20) == 0x20)
#else
		if ((in8 (ACTING_UART0_BASE + UART_LSR) & 0x20) == 0x20)
#endif
			break;
		udelay (100);
	}
#if defined(CONFIG_SERIAL_MULTI)
	out8 (dev_base + UART_THR, c);	/* put character out */
#else
	out8 (ACTING_UART0_BASE + UART_THR, c);	/* put character out */
#endif
}

#if defined(CONFIG_SERIAL_MULTI)
void serial_puts_dev (unsigned long dev_base, const char *s)
#else
void serial_puts (const char *s)
#endif
{
	while (*s) {
#if defined(CONFIG_SERIAL_MULTI)
		serial_putc_dev (dev_base, *s++);
#else
		serial_putc (*s++);
#endif
	}
}

#if defined(CONFIG_SERIAL_MULTI)
int serial_getc_dev (unsigned long dev_base)
#else
int serial_getc (void)
#endif
{
	unsigned char status = 0;

	while (1) {
#if defined(CONFIG_HW_WATCHDOG)
		WATCHDOG_RESET ();	/* Reset HW Watchdog, if needed */
#endif	/* CONFIG_HW_WATCHDOG */
#if defined(CONFIG_SERIAL_MULTI)
		status = in8 (dev_base + UART_LSR);
#else
		status = in8 (ACTING_UART0_BASE + UART_LSR);
#endif
		if ((status & asyncLSRDataReady1) != 0x0) {
			break;
		}
		if ((status & ( asyncLSRFramingError1 |
				asyncLSROverrunError1 |
				asyncLSRParityError1  |
				asyncLSRBreakInterrupt1 )) != 0) {
#if defined(CONFIG_SERIAL_MULTI)
			out8 (dev_base + UART_LSR,
#else
			out8 (ACTING_UART0_BASE + UART_LSR,
#endif
			      asyncLSRFramingError1 |
			      asyncLSROverrunError1 |
			      asyncLSRParityError1  |
			      asyncLSRBreakInterrupt1);
		}
	}
#if defined(CONFIG_SERIAL_MULTI)
	return (0x000000ff & (int) in8 (dev_base));
#else
	return (0x000000ff & (int) in8 (ACTING_UART0_BASE));
#endif
}

#if defined(CONFIG_SERIAL_MULTI)
int serial_tstc_dev (unsigned long dev_base)
#else
int serial_tstc (void)
#endif
{
	unsigned char status;

#if defined(CONFIG_SERIAL_MULTI)
	status = in8 (dev_base + UART_LSR);
#else
	status = in8 (ACTING_UART0_BASE + UART_LSR);
#endif
	if ((status & asyncLSRDataReady1) != 0x0) {
		return (1);
	}
	if ((status & ( asyncLSRFramingError1 |
			asyncLSROverrunError1 |
			asyncLSRParityError1  |
			asyncLSRBreakInterrupt1 )) != 0) {
#if defined(CONFIG_SERIAL_MULTI)
		out8 (dev_base + UART_LSR,
#else
		out8 (ACTING_UART0_BASE + UART_LSR,
#endif
		      asyncLSRFramingError1 |
		      asyncLSROverrunError1 |
		      asyncLSRParityError1  |
		      asyncLSRBreakInterrupt1);
	}
	return 0;
}

#ifdef CONFIG_SERIAL_SOFTWARE_FIFO

void serial_isr (void *arg)
{
	int space;
	int c;
	const int rx_get = buf_info.rx_get;
	int rx_put = buf_info.rx_put;

	if (rx_get <= rx_put) {
		space = CONFIG_SERIAL_SOFTWARE_FIFO - (rx_put - rx_get);
	} else {
		space = rx_get - rx_put;
	}
	while (serial_tstc_dev (ACTING_UART0_BASE)) {
		c = serial_getc_dev (ACTING_UART0_BASE);
		if (space) {
			buf_info.rx_buffer[rx_put++] = c;
			space--;
		}
		if (rx_put == CONFIG_SERIAL_SOFTWARE_FIFO)
			rx_put = 0;
		if (space < CONFIG_SERIAL_SOFTWARE_FIFO / 4) {
			/* Stop flow by setting RTS inactive */
			out8 (ACTING_UART0_BASE + UART_MCR,
			      in8 (ACTING_UART0_BASE + UART_MCR) & (0xFF ^ 0x02));
		}
	}
	buf_info.rx_put = rx_put;
}

void serial_buffered_init (void)
{
	serial_puts ("Switching to interrupt driven serial input mode.\n");
	buf_info.rx_buffer = malloc (CONFIG_SERIAL_SOFTWARE_FIFO);
	buf_info.rx_put = 0;
	buf_info.rx_get = 0;

	if (in8 (ACTING_UART0_BASE + UART_MSR) & 0x10) {
		serial_puts ("Check CTS signal present on serial port: OK.\n");
	} else {
		serial_puts ("WARNING: CTS signal not present on serial port.\n");
	}

	irq_install_handler ( VECNUM_U0 /*UART0 */ /*int vec */ ,
			      serial_isr /*interrupt_handler_t *handler */ ,
			      (void *) &buf_info /*void *arg */ );

	/* Enable "RX Data Available" Interrupt on UART */
	/* out8(ACTING_UART0_BASE + UART_IER, in8(ACTING_UART0_BASE + UART_IER) |0x01); */
	out8 (ACTING_UART0_BASE + UART_IER, 0x01);
	/* Set DTR active */
	out8 (ACTING_UART0_BASE + UART_MCR, in8 (ACTING_UART0_BASE + UART_MCR) | 0x01);
	/* Start flow by setting RTS active */
	out8 (ACTING_UART0_BASE + UART_MCR, in8 (ACTING_UART0_BASE + UART_MCR) | 0x02);
	/* Setup UART FIFO: RX trigger level: 4 byte, Enable FIFO */
	out8 (ACTING_UART0_BASE + UART_FCR, (1 << 6) | 1);
}

void serial_buffered_putc (const char c)
{
	/* Wait for CTS */
#if defined(CONFIG_HW_WATCHDOG)
	while (!(in8 (ACTING_UART0_BASE + UART_MSR) & 0x10))
		WATCHDOG_RESET ();
#else
	while (!(in8 (ACTING_UART0_BASE + UART_MSR) & 0x10));
#endif
	serial_putc (c);
}

void serial_buffered_puts (const char *s)
{
	serial_puts (s);
}

int serial_buffered_getc (void)
{
	int space;
	int c;
	int rx_get = buf_info.rx_get;
	int rx_put;

#if defined(CONFIG_HW_WATCHDOG)
	while (rx_get == buf_info.rx_put)
		WATCHDOG_RESET ();
#else
	while (rx_get == buf_info.rx_put);
#endif
	c = buf_info.rx_buffer[rx_get++];
	if (rx_get == CONFIG_SERIAL_SOFTWARE_FIFO)
		rx_get = 0;
	buf_info.rx_get = rx_get;

	rx_put = buf_info.rx_put;
	if (rx_get <= rx_put) {
		space = CONFIG_SERIAL_SOFTWARE_FIFO - (rx_put - rx_get);
	} else {
		space = rx_get - rx_put;
	}
	if (space > CONFIG_SERIAL_SOFTWARE_FIFO / 2) {
		/* Start flow by setting RTS active */
		out8 (ACTING_UART0_BASE + UART_MCR, in8 (ACTING_UART0_BASE + UART_MCR) | 0x02);
	}

	return c;
}

int serial_buffered_tstc (void)
{
	return (buf_info.rx_get != buf_info.rx_put) ? 1 : 0;
}

#endif	/* CONFIG_SERIAL_SOFTWARE_FIFO */

#if (CONFIG_COMMANDS & CFG_CMD_KGDB)
/*
  AS HARNOIS : according to CONFIG_KGDB_SER_INDEX kgdb uses serial port
  number 0 or number 1
  - if CONFIG_KGDB_SER_INDEX = 1 => serial port number 0 :
  configuration has been already done
  - if CONFIG_KGDB_SER_INDEX = 2 => serial port number 1 :
  configure port 1 for serial I/O with rate = CONFIG_KGDB_BAUDRATE
*/
#if (CONFIG_KGDB_SER_INDEX & 2)
void kgdb_serial_init (void)
{
	DECLARE_GLOBAL_DATA_PTR;

	volatile char val;
	unsigned short br_reg;

	get_clocks ();
	br_reg = (((((gd->cpu_clk / 16) / 18) * 10) / CONFIG_KGDB_BAUDRATE) +
		  5) / 10;
	/*
	 * Init onboard 16550 UART
	 */
	out8 (ACTING_UART1_BASE + UART_LCR, 0x80);	/* set DLAB bit */
	out8 (ACTING_UART1_BASE + UART_DLL, (br_reg & 0x00ff));	/* set divisor for 9600 baud */
	out8 (ACTING_UART1_BASE + UART_DLM, ((br_reg & 0xff00) >> 8));	/* set divisor for 9600 baud */
	out8 (ACTING_UART1_BASE + UART_LCR, 0x03);	/* line control 8 bits no parity */
	out8 (ACTING_UART1_BASE + UART_FCR, 0x00);	/* disable FIFO */
	out8 (ACTING_UART1_BASE + UART_MCR, 0x00);	/* no modem control DTR RTS */
	val = in8 (ACTING_UART1_BASE + UART_LSR);	/* clear line status */
	val = in8 (ACTING_UART1_BASE + UART_RBR);	/* read receive buffer */
	out8 (ACTING_UART1_BASE + UART_SCR, 0x00);	/* set scratchpad */
	out8 (ACTING_UART1_BASE + UART_IER, 0x00);	/* set interrupt enable reg */
}

void putDebugChar (const char c)
{
	if (c == '\n')
		serial_putc ('\r');

	out8 (ACTING_UART1_BASE + UART_THR, c);	/* put character out */

	/* check THRE bit, wait for transfer done */
	while ((in8 (ACTING_UART1_BASE + UART_LSR) & 0x20) != 0x20);
}

void putDebugStr (const char *s)
{
	while (*s) {
		serial_putc (*s++);
	}
}

int getDebugChar (void)
{
	unsigned char status = 0;

	while (1) {
		status = in8 (ACTING_UART1_BASE + UART_LSR);
		if ((status & asyncLSRDataReady1) != 0x0) {
			break;
		}
		if ((status & ( asyncLSRFramingError1 |
				asyncLSROverrunError1 |
				asyncLSRParityError1  |
				asyncLSRBreakInterrupt1 )) != 0) {
			out8 (ACTING_UART1_BASE + UART_LSR,
			      asyncLSRFramingError1 |
			      asyncLSROverrunError1 |
			      asyncLSRParityError1  |
			      asyncLSRBreakInterrupt1);
		}
	}
	return (0x000000ff & (int) in8 (ACTING_UART1_BASE));
}

void kgdb_interruptible (int yes)
{
	return;
}

#else	/* ! (CONFIG_KGDB_SER_INDEX & 2) */

void kgdb_serial_init (void)
{
	serial_printf ("[on serial] ");
}

void putDebugChar (int c)
{
	serial_putc (c);
}

void putDebugStr (const char *str)
{
	serial_puts (str);
}

int getDebugChar (void)
{
	return serial_getc ();
}

void kgdb_interruptible (int yes)
{
	return;
}
#endif	/* (CONFIG_KGDB_SER_INDEX & 2) */
#endif	/* CFG_CMD_KGDB */


#if defined(CONFIG_SERIAL_MULTI)
int serial0_init(void)
{
	return (serial_init_dev(UART0_BASE));
}

int serial1_init(void)
{
	return (serial_init_dev(UART1_BASE));
}
void serial0_setbrg (void)
{
	serial_setbrg_dev(UART0_BASE);
}
void serial1_setbrg (void)
{
	serial_setbrg_dev(UART1_BASE);
}

void serial0_putc(const char c)
{
	serial_putc_dev(UART0_BASE,c);
}

void serial1_putc(const char c)
{
	serial_putc_dev(UART1_BASE, c);
}
void serial0_puts(const char *s)
{
	serial_puts_dev(UART0_BASE, s);
}

void serial1_puts(const char *s)
{
	serial_puts_dev(UART1_BASE, s);
}

int serial0_getc(void)
{
	return(serial_getc_dev(UART0_BASE));
}

int serial1_getc(void)
{
	return(serial_getc_dev(UART1_BASE));
}
int serial0_tstc(void)
{
	return (serial_tstc_dev(UART0_BASE));
}

int serial1_tstc(void)
{
	return (serial_tstc_dev(UART1_BASE));
}

struct serial_device serial0_device =
{
	"serial0",
	"UART0",
	serial0_init,
	serial0_setbrg,
	serial0_getc,
	serial0_tstc,
	serial0_putc,
	serial0_puts,
};

struct serial_device serial1_device =
{
	"serial1",
	"UART1",
	serial1_init,
	serial1_setbrg,
	serial1_getc,
	serial1_tstc,
	serial1_putc,
	serial1_puts,
};
#endif /* CONFIG_SERIAL_MULTI */

#endif	/* CONFIG_405GP || CONFIG_405CR */