u-boot/arch/powerpc/cpu/mpc8xx/serial.c

/*
 * (C) Copyright 2000
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <commproc.h>
#include <command.h>
#include <serial.h>
#include <watchdog.h>
#include <linux/compiler.h>

DECLARE_GLOBAL_DATA_PTR;

#if !defined(CONFIG_8xx_CONS_NONE)	/* No Console at all */

#if defined(CONFIG_8xx_CONS_SMC1)	/* Console on SMC1 */
#define	SMC_INDEX	0
#define PROFF_SMC	PROFF_SMC1
#define CPM_CR_CH_SMC	CPM_CR_CH_SMC1

#elif defined(CONFIG_8xx_CONS_SMC2)	/* Console on SMC2 */
#define SMC_INDEX	1
#define PROFF_SMC	PROFF_SMC2
#define CPM_CR_CH_SMC	CPM_CR_CH_SMC2

#endif /* CONFIG_8xx_CONS_SMCx */

#if defined(CONFIG_8xx_CONS_SCC1)	/* Console on SCC1 */
#define SCC_INDEX	0
#define PROFF_SCC	PROFF_SCC1
#define CPM_CR_CH_SCC	CPM_CR_CH_SCC1

#elif defined(CONFIG_8xx_CONS_SCC2)	/* Console on SCC2 */
#define SCC_INDEX	1
#define PROFF_SCC	PROFF_SCC2
#define CPM_CR_CH_SCC	CPM_CR_CH_SCC2

#elif defined(CONFIG_8xx_CONS_SCC3)	/* Console on SCC3 */
#define SCC_INDEX	2
#define PROFF_SCC	PROFF_SCC3
#define CPM_CR_CH_SCC	CPM_CR_CH_SCC3

#elif defined(CONFIG_8xx_CONS_SCC4)	/* Console on SCC4 */
#define SCC_INDEX	3
#define PROFF_SCC	PROFF_SCC4
#define CPM_CR_CH_SCC	CPM_CR_CH_SCC4

#endif /* CONFIG_8xx_CONS_SCCx */

#if !defined(CONFIG_SYS_SMC_RXBUFLEN)
#define CONFIG_SYS_SMC_RXBUFLEN	1
#define CONFIG_SYS_MAXIDLE	0
#else
#if !defined(CONFIG_SYS_MAXIDLE)
#error "you must define CONFIG_SYS_MAXIDLE"
#endif
#endif

typedef volatile struct serialbuffer {
	cbd_t	rxbd;		/* Rx BD */
	cbd_t	txbd;		/* Tx BD */
	uint	rxindex;	/* index for next character to read */
	volatile uchar	rxbuf[CONFIG_SYS_SMC_RXBUFLEN];/* rx buffers */
	volatile uchar	txbuf;	/* tx buffers */
} serialbuffer_t;

static void serial_setdivisor(volatile cpm8xx_t *cp)
{
	int divisor=(gd->cpu_clk + 8*gd->baudrate)/16/gd->baudrate;

	if(divisor/16>0x1000) {
		/* bad divisor, assume 50MHz clock and 9600 baud */
		divisor=(50*1000*1000 + 8*9600)/16/9600;
	}

#ifdef CONFIG_SYS_BRGCLK_PRESCALE
	divisor /= CONFIG_SYS_BRGCLK_PRESCALE;
#endif

	if(divisor<=0x1000) {
		cp->cp_brgc1=((divisor-1)<<1) | CPM_BRG_EN;
	} else {
		cp->cp_brgc1=((divisor/16-1)<<1) | CPM_BRG_EN | CPM_BRG_DIV16;
	}
}

#if (defined (CONFIG_8xx_CONS_SMC1) || defined (CONFIG_8xx_CONS_SMC2))

/*
 * Minimal serial functions needed to use one of the SMC ports
 * as serial console interface.
 */

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

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

	cp->cp_simode = 0x00000000;

	serial_setdivisor(cp);
}

static int smc_init (void)
{
	volatile immap_t *im = (immap_t *)CONFIG_SYS_IMMR;
	volatile smc_t *sp;
	volatile smc_uart_t *up;
	volatile cpm8xx_t *cp = &(im->im_cpm);
#if (!defined(CONFIG_8xx_CONS_SMC1)) && (defined(CONFIG_MPC823) || defined(CONFIG_MPC850))
	volatile iop8xx_t *ip = (iop8xx_t *)&(im->im_ioport);
#endif
	uint	dpaddr;
	volatile serialbuffer_t *rtx;

	/* initialize pointers to SMC */

	sp = (smc_t *) &(cp->cp_smc[SMC_INDEX]);
	up = (smc_uart_t *) &cp->cp_dparam[PROFF_SMC];
#ifdef CONFIG_SYS_SMC_UCODE_PATCH
	up = (smc_uart_t *) &cp->cp_dpmem[up->smc_rpbase];
#else
	/* Disable relocation */
	up->smc_rpbase = 0;
#endif

	/* Disable transmitter/receiver. */
	sp->smc_smcmr &= ~(SMCMR_REN | SMCMR_TEN);

	/* Enable SDMA. */
	im->im_siu_conf.sc_sdcr = 1;

	/* clear error conditions */
#ifdef	CONFIG_SYS_SDSR
	im->im_sdma.sdma_sdsr = CONFIG_SYS_SDSR;
#else
	im->im_sdma.sdma_sdsr = 0x83;
#endif

	/* clear SDMA interrupt mask */
#ifdef	CONFIG_SYS_SDMR
	im->im_sdma.sdma_sdmr = CONFIG_SYS_SDMR;
#else
	im->im_sdma.sdma_sdmr = 0x00;
#endif

#if defined(CONFIG_8xx_CONS_SMC1)
	/* Use Port B for SMC1 instead of other functions. */
	cp->cp_pbpar |=  0x000000c0;
	cp->cp_pbdir &= ~0x000000c0;
	cp->cp_pbodr &= ~0x000000c0;
#else	/* CONFIG_8xx_CONS_SMC2 */
# if defined(CONFIG_MPC823) || defined(CONFIG_MPC850)
	/* Use Port A for SMC2 instead of other functions. */
	ip->iop_papar |=  0x00c0;
	ip->iop_padir &= ~0x00c0;
	ip->iop_paodr &= ~0x00c0;
# else	/* must be a 860 then */
	/* Use Port B for SMC2 instead of other functions.
	 */
	cp->cp_pbpar |=  0x00000c00;
	cp->cp_pbdir &= ~0x00000c00;
	cp->cp_pbodr &= ~0x00000c00;
# endif
#endif

	/* Set the physical address of the host memory buffers in
	 * the buffer descriptors.
	 */
	dpaddr = CPM_SERIAL_BASE;

	rtx = (serialbuffer_t *)&cp->cp_dpmem[dpaddr];
	/* Allocate space for two buffer descriptors in the DP ram.
	 * For now, this address seems OK, but it may have to
	 * change with newer versions of the firmware.
	 * damm: allocating space after the two buffers for rx/tx data
	 */

	rtx->rxbd.cbd_bufaddr = (uint) &rtx->rxbuf;
	rtx->rxbd.cbd_sc      = 0;

	rtx->txbd.cbd_bufaddr = (uint) &rtx->txbuf;
	rtx->txbd.cbd_sc      = 0;

	/* Set up the uart parameters in the parameter ram. */
	up->smc_rbase = dpaddr;
	up->smc_tbase = dpaddr+sizeof(cbd_t);
	up->smc_rfcr = SMC_EB;
	up->smc_tfcr = SMC_EB;
#if defined (CONFIG_SYS_SMC_UCODE_PATCH)
	up->smc_rbptr = up->smc_rbase;
	up->smc_tbptr = up->smc_tbase;
	up->smc_rstate = 0;
	up->smc_tstate = 0;
#endif

	/* Set UART mode, 8 bit, no parity, one stop.
	 * Enable receive and transmit.
	 */
	sp->smc_smcmr = smcr_mk_clen(9) |  SMCMR_SM_UART;

	/* Mask all interrupts and remove anything pending.
	*/
	sp->smc_smcm = 0;
	sp->smc_smce = 0xff;

#ifdef CONFIG_SYS_SPC1920_SMC1_CLK4
	/* clock source is PLD */

	/* set freq to 19200 Baud */
	*((volatile uchar *) CONFIG_SYS_SPC1920_PLD_BASE+6) = 0x3;
	/* configure clk4 as input */
	im->im_ioport.iop_pdpar |= 0x800;
	im->im_ioport.iop_pddir &= ~0x800;

	cp->cp_simode = ((cp->cp_simode & ~0xf000) | 0x7000);
#else
	/* Set up the baud rate generator */
	smc_setbrg ();
#endif

	/* Make the first buffer the only buffer. */
	rtx->txbd.cbd_sc |= BD_SC_WRAP;
	rtx->rxbd.cbd_sc |= BD_SC_EMPTY | BD_SC_WRAP;

	/* single/multi character receive. */
	up->smc_mrblr = CONFIG_SYS_SMC_RXBUFLEN;
	up->smc_maxidl = CONFIG_SYS_MAXIDLE;
	rtx->rxindex = 0;

	/* 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_SMC, CPM_CR_INIT_TRX) | CPM_CR_FLG;

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

	/* Enable transmitter/receiver.	*/
	sp->smc_smcmr |= SMCMR_REN | SMCMR_TEN;

	return (0);
}

static void
smc_putc(const char c)
{
	volatile smc_uart_t	*up;
	volatile immap_t	*im = (immap_t *)CONFIG_SYS_IMMR;
	volatile cpm8xx_t	*cpmp = &(im->im_cpm);
	volatile serialbuffer_t	*rtx;

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

	up = (smc_uart_t *)&cpmp->cp_dparam[PROFF_SMC];
#ifdef CONFIG_SYS_SMC_UCODE_PATCH
	up = (smc_uart_t *) &cpmp->cp_dpmem[up->smc_rpbase];
#endif

	rtx = (serialbuffer_t *)&cpmp->cp_dpmem[up->smc_rbase];

	/* Wait for last character to go. */
	rtx->txbuf = c;
	rtx->txbd.cbd_datlen = 1;
	rtx->txbd.cbd_sc |= BD_SC_READY;
	__asm__("eieio");

	while (rtx->txbd.cbd_sc & BD_SC_READY) {
		WATCHDOG_RESET ();
		__asm__("eieio");
	}
}

static void
smc_puts (const char *s)
{
	while (*s) {
		smc_putc (*s++);
	}
}

static int
smc_getc(void)
{
	volatile smc_uart_t	*up;
	volatile immap_t	*im = (immap_t *)CONFIG_SYS_IMMR;
	volatile cpm8xx_t	*cpmp = &(im->im_cpm);
	volatile serialbuffer_t	*rtx;
	unsigned char  c;

	up = (smc_uart_t *)&cpmp->cp_dparam[PROFF_SMC];
#ifdef CONFIG_SYS_SMC_UCODE_PATCH
	up = (smc_uart_t *) &cpmp->cp_dpmem[up->smc_rpbase];
#endif
	rtx = (serialbuffer_t *)&cpmp->cp_dpmem[up->smc_rbase];

	/* Wait for character to show up. */
	while (rtx->rxbd.cbd_sc & BD_SC_EMPTY)
		WATCHDOG_RESET ();

	/* the characters are read one by one,
	 * use the rxindex to know the next char to deliver
	 */
	c = *(unsigned char *) (rtx->rxbd.cbd_bufaddr+rtx->rxindex);
	rtx->rxindex++;

	/* check if all char are readout, then make prepare for next receive */
	if (rtx->rxindex >= rtx->rxbd.cbd_datlen) {
		rtx->rxindex = 0;
		rtx->rxbd.cbd_sc |= BD_SC_EMPTY;
	}
	return(c);
}

static int
smc_tstc(void)
{
	volatile smc_uart_t	*up;
	volatile immap_t	*im = (immap_t *)CONFIG_SYS_IMMR;
	volatile cpm8xx_t	*cpmp = &(im->im_cpm);
	volatile serialbuffer_t	*rtx;

	up = (smc_uart_t *)&cpmp->cp_dparam[PROFF_SMC];
#ifdef CONFIG_SYS_SMC_UCODE_PATCH
	up = (smc_uart_t *) &cpmp->cp_dpmem[up->smc_rpbase];
#endif

	rtx = (serialbuffer_t *)&cpmp->cp_dpmem[up->smc_rbase];

	return !(rtx->rxbd.cbd_sc & BD_SC_EMPTY);
}

struct serial_device serial_smc_device =
{
	.name	= "serial_smc",
	.start	= smc_init,
	.stop	= NULL,
	.setbrg	= smc_setbrg,
	.getc	= smc_getc,
	.tstc	= smc_tstc,
	.putc	= smc_putc,
	.puts	= 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 *)CONFIG_SYS_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 *)CONFIG_SYS_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];

	/* 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)
	/*
	 * 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)));
#endif

	/* Allocate space for two buffer descriptors in the DP ram. */
	dpaddr = dpram_alloc_align(sizeof(cbd_t)*2 + 2, 8);

	/* 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 *)CONFIG_SYS_IMMR;
	volatile cpm8xx_t	*cpmp = &(im->im_cpm);

	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 *)CONFIG_SYS_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 *)CONFIG_SYS_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 =
{
	.name	= "serial_scc",
	.start	= scc_init,
	.stop	= NULL,
	.setbrg	= scc_setbrg,
	.getc	= scc_getc,
	.tstc	= scc_tstc,
	.putc	= scc_putc,
	.puts	= scc_puts,
};

#endif	/* CONFIG_8xx_CONS_SCCx */

__weak struct serial_device *default_serial_console(void)
{
#if defined(CONFIG_8xx_CONS_SMC1) || defined(CONFIG_8xx_CONS_SMC2)
	return &serial_smc_device;
#else
	return &serial_scc_device;
#endif
}

void mpc8xx_serial_initialize(void)
{
#if defined(CONFIG_8xx_CONS_SMC1) || defined(CONFIG_8xx_CONS_SMC2)
	serial_register(&serial_smc_device);
#endif
#if	defined(CONFIG_8xx_CONS_SCC1) || defined(CONFIG_8xx_CONS_SCC2) || \
	defined(CONFIG_8xx_CONS_SCC3) || defined(CONFIG_8xx_CONS_SCC4)
	serial_register(&serial_scc_device);
#endif
}

#if defined(CONFIG_CMD_KGDB)

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

	if (strcmp(default_serial_console()->name, "serial_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()->name, "serial_scc") == 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()->name, 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 */