linux/arch/powerpc/boot/uartlite.c

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/*
* Xilinx UARTLITE bootloader driver
*
* Copyright (C) 2007 Secret Lab Technologies Ltd.
*
* This file is licensed under the terms of the GNU General Public License
* version 2. This program is licensed "as is" without any warranty of any
* kind, whether express or implied.
*/
#include <stdarg.h>
#include <stddef.h>
#include "types.h"
#include "string.h"
#include "stdio.h"
#include "io.h"
#include "ops.h"
static void * reg_base;
static int uartlite_open(void)
{
/* Clear the RX FIFO */
out_be32(reg_base + 0x0C, 0x2);
return 0;
}
static void uartlite_putc(unsigned char c)
{
while ((in_be32(reg_base + 0x8) & 0x08) != 0); /* spin */
out_be32(reg_base + 0x4, c);
}
static unsigned char uartlite_getc(void)
{
while ((in_be32(reg_base + 0x8) & 0x01) == 0); /* spin */
return in_be32(reg_base);
}
static u8 uartlite_tstc(void)
{
return ((in_be32(reg_base + 0x8) & 0x01) != 0);
}
int uartlite_console_init(void *devp, struct serial_console_data *scdp)
{
int n;
unsigned long reg_phys;
n = getprop(devp, "virtual-reg", &reg_base, sizeof(reg_base));
if (n != sizeof(reg_base)) {
if (!dt_xlate_reg(devp, 0, &reg_phys, NULL))
return -1;
reg_base = (void *)reg_phys;
}
scdp->open = uartlite_open;
scdp->putc = uartlite_putc;
scdp->getc = uartlite_getc;
scdp->tstc = uartlite_tstc;
scdp->close = NULL;
return 0;
}