mpc52xx-psc.c
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/*
* MPC5200 PSC serial console support.
*
* Author: Grant Likely <grant.likely@secretlab.ca>
*
* Copyright (c) 2007 Secret Lab Technologies Ltd.
* Copyright (c) 2007 Freescale Semiconductor, Inc.
*
* It is assumed that the firmware (or the platform file) has already set
* up the port.
*/
#include "types.h"
#include "io.h"
#include "ops.h"
/* Programmable Serial Controller (PSC) status register bits */
#define MPC52xx_PSC_SR 0x04
#define MPC52xx_PSC_SR_RXRDY 0x0100
#define MPC52xx_PSC_SR_RXFULL 0x0200
#define MPC52xx_PSC_SR_TXRDY 0x0400
#define MPC52xx_PSC_SR_TXEMP 0x0800
#define MPC52xx_PSC_BUFFER 0x0C
static void *psc;
static int psc_open(void)
{
/* Assume the firmware has already configured the PSC into
* uart mode */
return 0;
}
static void psc_putc(unsigned char c)
{
while (!(in_be16(psc + MPC52xx_PSC_SR) & MPC52xx_PSC_SR_TXRDY)) ;
out_8(psc + MPC52xx_PSC_BUFFER, c);
}
static unsigned char psc_tstc(void)
{
return (in_be16(psc + MPC52xx_PSC_SR) & MPC52xx_PSC_SR_RXRDY) != 0;
}
static unsigned char psc_getc(void)
{
while (!(in_be16(psc + MPC52xx_PSC_SR) & MPC52xx_PSC_SR_RXRDY)) ;
return in_8(psc + MPC52xx_PSC_BUFFER);
}
int mpc5200_psc_console_init(void *devp, struct serial_console_data *scdp)
{
/* Get the base address of the psc registers */
if (dt_get_virtual_reg(devp, &psc, 1) < 1)
return -1;
scdp->open = psc_open;
scdp->putc = psc_putc;
scdp->getc = psc_getc;
scdp->tstc = psc_tstc;
return 0;
}