u-boot/drivers/serial/atmel_usart.c
Andreas Bießmann 125637c572 atmel_usart: change register access to C structure
This patch introduces C structure definition for register footprint of atmel's
 usart.

Signed-off-by: Andreas Bießmann <biessmann@corscience.de>
2010-10-05 16:58:56 +02:00

111 lines
2.8 KiB
C

/*
* Copyright (C) 2004-2006 Atmel Corporation
*
* Modified to support C structur SoC access by
* Andreas Bießmann <biessmann@corscience.de>
*
* 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
*/
#include <common.h>
#include <watchdog.h>
#include <asm/io.h>
#include <asm/arch/clk.h>
#include <asm/arch/memory-map.h>
#if defined(CONFIG_USART0)
# define USART_ID 0
# define USART_BASE USART0_BASE
#elif defined(CONFIG_USART1)
# define USART_ID 1
# define USART_BASE USART1_BASE
#elif defined(CONFIG_USART2)
# define USART_ID 2
# define USART_BASE USART2_BASE
#elif defined(CONFIG_USART3)
# define USART_ID 3
# define USART_BASE USART3_BASE
#endif
#include "atmel_usart.h"
DECLARE_GLOBAL_DATA_PTR;
void serial_setbrg(void)
{
atmel_usart3_t *usart = (atmel_usart3_t*)USART_BASE;
unsigned long divisor;
unsigned long usart_hz;
/*
* Master Clock
* Baud Rate = --------------
* 16 * CD
*/
usart_hz = get_usart_clk_rate(USART_ID);
divisor = (usart_hz / 16 + gd->baudrate / 2) / gd->baudrate;
writel(USART3_BF(CD, divisor), &usart->brgr);
}
int serial_init(void)
{
atmel_usart3_t *usart = (atmel_usart3_t*)USART_BASE;
writel(USART3_BIT(RSTRX) | USART3_BIT(RSTTX), &usart->cr);
serial_setbrg();
writel(USART3_BIT(RXEN) | USART3_BIT(TXEN), &usart->cr);
writel((USART3_BF(USART_MODE, USART3_USART_MODE_NORMAL)
| USART3_BF(USCLKS, USART3_USCLKS_MCK)
| USART3_BF(CHRL, USART3_CHRL_8)
| USART3_BF(PAR, USART3_PAR_NONE)
| USART3_BF(NBSTOP, USART3_NBSTOP_1)),
&usart->mr);
return 0;
}
void serial_putc(char c)
{
atmel_usart3_t *usart = (atmel_usart3_t*)USART_BASE;
if (c == '\n')
serial_putc('\r');
while (!(readl(&usart->csr) & USART3_BIT(TXRDY)));
writel(c, &usart->thr);
}
void serial_puts(const char *s)
{
while (*s)
serial_putc(*s++);
}
int serial_getc(void)
{
atmel_usart3_t *usart = (atmel_usart3_t*)USART_BASE;
while (!(readl(&usart->csr) & USART3_BIT(RXRDY)))
WATCHDOG_RESET();
return readl(&usart->rhr);
}
int serial_tstc(void)
{
atmel_usart3_t *usart = (atmel_usart3_t*)USART_BASE;
return (readl(&usart->csr) & USART3_BIT(RXRDY)) != 0;
}