u-boot/cpu/mpc8220/uart.c

126 lines
3 KiB
C

/*
* (C) Copyright 2004, Freescale, Inc
* TsiChung Liew, Tsi-Chung.Liew@freescale.com.
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*
*/
/*
* Minimal serial functions needed to use one of the PSC ports
* as serial console interface.
*/
#include <common.h>
#include <mpc8220.h>
DECLARE_GLOBAL_DATA_PTR;
#define PSC_BASE MMAP_PSC1
#if defined(CONFIG_PSC_CONSOLE)
int serial_init (void)
{
volatile psc8220_t *psc = (psc8220_t *) PSC_BASE;
u32 counter;
/* write to SICR: SIM2 = uart mode,dcd does not affect rx */
psc->cr = 0;
psc->ipcr_acr = 0;
psc->isr_imr = 0;
/* write to CSR: RX/TX baud rate from timers */
psc->sr_csr = 0xdd000000;
psc->mr1_2 = PSC_MR1_BITS_CHAR_8 | PSC_MR1_NO_PARITY | PSC_MR2_STOP_BITS_1;
/* Setting up BaudRate */
counter = ((gd->bus_clk / gd->baudrate)) >> 5;
counter++;
/* write to CTUR: divide counter upper byte */
psc->ctur = ((counter & 0xff00) << 16);
/* write to CTLR: divide counter lower byte */
psc->ctlr = ((counter & 0x00ff) << 24);
psc->cr = PSC_CR_RST_RX_CMD;
psc->cr = PSC_CR_RST_TX_CMD;
psc->cr = PSC_CR_RST_ERR_STS_CMD;
psc->cr = PSC_CR_RST_BRK_INT_CMD;
psc->cr = PSC_CR_RST_MR_PTR_CMD;
psc->cr = PSC_CR_RX_ENABLE | PSC_CR_TX_ENABLE;
return (0);
}
void serial_putc (const char c)
{
volatile psc8220_t *psc = (psc8220_t *) PSC_BASE;
if (c == '\n')
serial_putc ('\r');
/* Wait for last character to go. */
while (!(psc->sr_csr & PSC_SR_TXRDY));
psc->xmitbuf[0] = c;
}
void serial_puts (const char *s)
{
while (*s) {
serial_putc (*s++);
}
}
int serial_getc (void)
{
volatile psc8220_t *psc = (psc8220_t *) PSC_BASE;
/* Wait for a character to arrive. */
while (!(psc->sr_csr & PSC_SR_RXRDY));
return psc->xmitbuf[2];
}
int serial_tstc (void)
{
volatile psc8220_t *psc = (psc8220_t *) PSC_BASE;
return (psc->sr_csr & PSC_SR_RXRDY);
}
void serial_setbrg (void)
{
volatile psc8220_t *psc = (psc8220_t *) PSC_BASE;
u32 counter;
counter = ((gd->bus_clk / gd->baudrate)) >> 5;
counter++;
/* write to CTUR: divide counter upper byte */
psc->ctur = ((counter & 0xff00) << 16);
/* write to CTLR: divide counter lower byte */
psc->ctlr = ((counter & 0x00ff) << 24);
psc->cr = PSC_CR_RST_RX_CMD;
psc->cr = PSC_CR_RST_TX_CMD;
psc->cr = PSC_CR_RX_ENABLE | PSC_CR_TX_ENABLE;
}
#endif /* CONFIG_PSC_CONSOLE */