serial.c

U-boot源码 ARM7启动代码

	smc_getc,
	smc_tstc,
	smc_putc,
	smc_puts,
};

#endif /* CONFIG_8xx_CONS_SMC1 || CONFIG_8xx_CONS_SMC2 */

#if defined(CONFIG_8xx_CONS_SCC1) || defined(CONFIG_8xx_CONS_SCC2) || \
    defined(CONFIG_8xx_CONS_SCC3) || defined(CONFIG_8xx_CONS_SCC4)

static void
scc_setbrg (void)
{
	volatile immap_t *im = (immap_t *)CFG_IMMR;
	volatile cpm8xx_t *cp = &(im->im_cpm);

	/* Set up the baud rate generator.
	 * See 8xx_io/commproc.c for details.
	 *
	 * Wire BRG1 to SCCx
	 */

	cp->cp_sicr &= ~(0x000000FF << (8 * SCC_INDEX));

	serial_setdivisor(cp);
}

static int scc_init (void)
{
	volatile immap_t *im = (immap_t *)CFG_IMMR;
	volatile scc_t *sp;
	volatile scc_uart_t *up;
	volatile cbd_t *tbdf, *rbdf;
	volatile cpm8xx_t *cp = &(im->im_cpm);
	uint	 dpaddr;
#if (SCC_INDEX != 2) || !defined(CONFIG_MPC850)
	volatile iop8xx_t *ip = (iop8xx_t *)&(im->im_ioport);
#endif

	/* initialize pointers to SCC */

	sp = (scc_t *) &(cp->cp_scc[SCC_INDEX]);
	up = (scc_uart_t *) &cp->cp_dparam[PROFF_SCC];

#if defined(CONFIG_LWMON) && defined(CONFIG_8xx_CONS_SCC2)
    {	/* Disable Ethernet, enable Serial */
	uchar c;

	c = pic_read  (0x61);
	c &= ~0x40;	/* enable COM3 */
	c |=  0x80;	/* disable Ethernet */
	pic_write (0x61, c);

	/* enable RTS2 */
	cp->cp_pbpar |=  0x2000;
	cp->cp_pbdat |=  0x2000;
	cp->cp_pbdir |=  0x2000;
    }
#endif	/* CONFIG_LWMON */

	/* Disable transmitter/receiver.
	*/
	sp->scc_gsmrl &= ~(SCC_GSMRL_ENR | SCC_GSMRL_ENT);

#if (SCC_INDEX == 2) && defined(CONFIG_MPC850)
	/*
	 * The MPC850 has SCC3 on Port B
	 */
	cp->cp_pbpar |=  0x06;
	cp->cp_pbdir &= ~0x06;
	cp->cp_pbodr &= ~0x06;

#elif (SCC_INDEX < 2) || !defined(CONFIG_IP860)
	/*
	 * Standard configuration for SCC's is on Part A
	 */
	ip->iop_papar |=  ((3 << (2 * SCC_INDEX)));
	ip->iop_padir &= ~((3 << (2 * SCC_INDEX)));
	ip->iop_paodr &= ~((3 << (2 * SCC_INDEX)));
#else
	/*
	 * The IP860 has SCC3 and SCC4 on Port D
	 */
	ip->iop_pdpar |=  ((3 << (2 * SCC_INDEX)));
#endif

	/* Allocate space for two buffer descriptors in the DP ram.
	 */

#ifdef CFG_ALLOC_DPRAM
	dpaddr = dpram_alloc_align (sizeof(cbd_t)*2 + 2, 8) ;
#else
	dpaddr = CPM_SERIAL2_BASE ;
#endif

	/* Enable SDMA.
	*/
	im->im_siu_conf.sc_sdcr = 0x0001;

	/* Set the physical address of the host memory buffers in
	 * the buffer descriptors.
	 */

	rbdf = (cbd_t *)&cp->cp_dpmem[dpaddr];
	rbdf->cbd_bufaddr = (uint) (rbdf+2);
	rbdf->cbd_sc = 0;
	tbdf = rbdf + 1;
	tbdf->cbd_bufaddr = ((uint) (rbdf+2)) + 1;
	tbdf->cbd_sc = 0;

	/* Set up the baud rate generator.
	*/
	scc_setbrg ();

	/* Set up the uart parameters in the parameter ram.
	*/
	up->scc_genscc.scc_rbase = dpaddr;
	up->scc_genscc.scc_tbase = dpaddr+sizeof(cbd_t);

	/* Initialize Tx/Rx parameters.
	*/
	while (cp->cp_cpcr & CPM_CR_FLG)  /* wait if cp is busy */
		;
	cp->cp_cpcr = mk_cr_cmd(CPM_CR_CH_SCC, CPM_CR_INIT_TRX) | CPM_CR_FLG;

	while (cp->cp_cpcr & CPM_CR_FLG)  /* wait if cp is busy */
		;

	up->scc_genscc.scc_rfcr  = SCC_EB | 0x05;
	up->scc_genscc.scc_tfcr  = SCC_EB | 0x05;

	up->scc_genscc.scc_mrblr = 1;	/* Single character receive */
	up->scc_maxidl = 0;		/* disable max idle */
	up->scc_brkcr  = 1;		/* send one break character on stop TX */
	up->scc_parec  = 0;
	up->scc_frmec  = 0;
	up->scc_nosec  = 0;
	up->scc_brkec  = 0;
	up->scc_uaddr1 = 0;
	up->scc_uaddr2 = 0;
	up->scc_toseq  = 0;
	up->scc_char1  = 0x8000;
	up->scc_char2  = 0x8000;
	up->scc_char3  = 0x8000;
	up->scc_char4  = 0x8000;
	up->scc_char5  = 0x8000;
	up->scc_char6  = 0x8000;
	up->scc_char7  = 0x8000;
	up->scc_char8  = 0x8000;
	up->scc_rccm   = 0xc0ff;

	/* Set low latency / small fifo.
	 */
	sp->scc_gsmrh = SCC_GSMRH_RFW;

	/* Set SCC(x) clock mode to 16x
	 * See 8xx_io/commproc.c for details.
	 *
	 * Wire BRG1 to SCCn
	 */

	/* Set UART mode, clock divider 16 on Tx and Rx
	 */
	sp->scc_gsmrl &= ~0xF;
	sp->scc_gsmrl |=
		(SCC_GSMRL_MODE_UART | SCC_GSMRL_TDCR_16 | SCC_GSMRL_RDCR_16);

	sp->scc_psmr  = 0;
	sp->scc_psmr  |= SCU_PSMR_CL;

	/* Mask all interrupts and remove anything pending.
	*/
	sp->scc_sccm = 0;
	sp->scc_scce = 0xffff;
	sp->scc_dsr  = 0x7e7e;
	sp->scc_psmr = 0x3000;

	/* Make the first buffer the only buffer.
	*/
	tbdf->cbd_sc |= BD_SC_WRAP;
	rbdf->cbd_sc |= BD_SC_EMPTY | BD_SC_WRAP;

	/* Enable transmitter/receiver.
	*/
	sp->scc_gsmrl |= (SCC_GSMRL_ENR | SCC_GSMRL_ENT);

	return (0);
}

static void
scc_putc(const char c)
{
	volatile cbd_t		*tbdf;
	volatile char		*buf;
	volatile scc_uart_t	*up;
	volatile immap_t	*im = (immap_t *)CFG_IMMR;
	volatile cpm8xx_t	*cpmp = &(im->im_cpm);

#ifdef CONFIG_MODEM_SUPPORT
	if (gd->be_quiet)
		return;
#endif

	if (c == '\n')
		scc_putc ('\r');

	up = (scc_uart_t *)&cpmp->cp_dparam[PROFF_SCC];

	tbdf = (cbd_t *)&cpmp->cp_dpmem[up->scc_genscc.scc_tbase];

	/* Wait for last character to go.
	*/

	buf = (char *)tbdf->cbd_bufaddr;

	*buf = c;
	tbdf->cbd_datlen = 1;
	tbdf->cbd_sc |= BD_SC_READY;
	__asm__("eieio");

	while (tbdf->cbd_sc & BD_SC_READY) {
		__asm__("eieio");
		WATCHDOG_RESET ();
	}
}

static void
scc_puts (const char *s)
{
	while (*s) {
		scc_putc (*s++);
	}
}

static int
scc_getc(void)
{
	volatile cbd_t		*rbdf;
	volatile unsigned char	*buf;
	volatile scc_uart_t	*up;
	volatile immap_t	*im = (immap_t *)CFG_IMMR;
	volatile cpm8xx_t	*cpmp = &(im->im_cpm);
	unsigned char		c;

	up = (scc_uart_t *)&cpmp->cp_dparam[PROFF_SCC];

	rbdf = (cbd_t *)&cpmp->cp_dpmem[up->scc_genscc.scc_rbase];

	/* Wait for character to show up.
	*/
	buf = (unsigned char *)rbdf->cbd_bufaddr;

	while (rbdf->cbd_sc & BD_SC_EMPTY)
		WATCHDOG_RESET ();

	c = *buf;
	rbdf->cbd_sc |= BD_SC_EMPTY;

	return(c);
}

static int
scc_tstc(void)
{
	volatile cbd_t		*rbdf;
	volatile scc_uart_t	*up;
	volatile immap_t	*im = (immap_t *)CFG_IMMR;
	volatile cpm8xx_t	*cpmp = &(im->im_cpm);

	up = (scc_uart_t *)&cpmp->cp_dparam[PROFF_SCC];

	rbdf = (cbd_t *)&cpmp->cp_dpmem[up->scc_genscc.scc_rbase];

	return(!(rbdf->cbd_sc & BD_SC_EMPTY));
}

struct serial_device serial_scc_device =
{
	"serial_scc",
	"SCC",
	scc_init,
	scc_setbrg,
	scc_getc,
	scc_tstc,
	scc_putc,
	scc_puts,
};

#endif	/* CONFIG_8xx_CONS_SCCx */

#ifdef CONFIG_MODEM_SUPPORT
void disable_putc(void)
{
	gd->be_quiet = 1;
}

void enable_putc(void)
{
	gd->be_quiet = 0;
}
#endif

#if defined(CONFIG_CMD_KGDB)

void
kgdb_serial_init(void)
{
	int i = -1;

	if (strcmp(default_serial_console()->ctlr, "SMC") == 0)
	{
#if defined(CONFIG_8xx_CONS_SMC1)
		i = 1;
#elif defined(CONFIG_8xx_CONS_SMC2)
		i = 2;
#endif
	}
	else if (strcmp(default_serial_console()->ctlr, "SMC") == 0)
	{
#if defined(CONFIG_8xx_CONS_SCC1)
		i = 1;
#elif defined(CONFIG_8xx_CONS_SCC2)
		i = 2;
#elif defined(CONFIG_8xx_CONS_SCC3)
		i = 3;
#elif defined(CONFIG_8xx_CONS_SCC4)
		i = 4;
#endif
	}

	if (i >= 0)
	{
		serial_printf("[on %s%d] ", default_serial_console()->ctlr, i);
	}
}

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

#endif	/* CONFIG_8xx_CONS_NONE */