cpu/arm920t/at91rm9200/serial.c

   1 /*
   2  * (C) Copyright 2002
   3  * Lineo, Inc <www.lineo.com>
   4  * Bernhard Kuhn <bkuhn@lineo.com>
   5  *
   6  * (C) Copyright 2002
   7  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
   8  * Marius Groeger <mgroeger@sysgo.de>
   9  *
  10  * (C) Copyright 2002
  11  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
  12  * Alex Zuepke <azu@sysgo.de>
  13  *
  14  * Copyright (C) 1999 2000 2001 Erik Mouw (J.A.K.Mouw@its.tudelft.nl)
  15  *
  16  * This program is free software; you can redistribute it and/or modify
  17  * it under the terms of the GNU General Public License as published by
  18  * the Free Software Foundation; either version 2 of the License, or
  19  * (at your option) any later version.
  20  *
  21  * This program is distributed in the hope that it will be useful,
  22  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  23  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  24  * GNU General Public License for more details.
  25  *
  26  * You should have received a copy of the GNU General Public License
  27  * along with this program; if not, write to the Free Software
  28  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  29  *
  30  */
  31
  32 #include <common.h>
  33 #include <asm/io.h>
  34 #include <asm/arch/hardware.h>
  35
  36 DECLARE_GLOBAL_DATA_PTR;
  37
  38 #if !defined(CONFIG_DBGU) && !defined(CONFIG_USART0) && !defined(CONFIG_USART1)
  39 #error must define one of CONFIG_DBGU or CONFIG_USART0 or CONFIG_USART1
  40 #endif
  41
  42 /* ggi thunder */
  43 #ifdef CONFIG_DBGU
  44 AT91PS_USART us = (AT91PS_USART) AT91C_BASE_DBGU;
  45 #endif
  46 #ifdef CONFIG_USART0
  47 AT91PS_USART us = (AT91PS_USART) AT91C_BASE_US0;
  48 #endif
  49 #ifdef CONFIG_USART1
  50 AT91PS_USART us = (AT91PS_USART) AT91C_BASE_US1;
  51 #endif
  52
  53 void serial_setbrg (void)
  54 {
  55         int baudrate;
  56
  57         if ((baudrate = gd->baudrate) <= 0)
  58                 baudrate = CONFIG_BAUDRATE;
  59         /* MASTER_CLOCK/(16 * baudrate) */
  60         us->US_BRGR = (AT91C_MASTER_CLOCK >> 4) / (unsigned)baudrate;
  61 }
  62
  63 int serial_init (void)
  64 {
  65         /* make any port initializations specific to this port */
  66 #ifdef CONFIG_DBGU
  67         *AT91C_PIOA_PDR = AT91C_PA31_DTXD | AT91C_PA30_DRXD;    /* PA 31 & 30 */
  68         *AT91C_PMC_PCER = 1 << AT91C_ID_SYS;    /* enable clock */
  69 #endif
  70 #ifdef CONFIG_USART0
  71         *AT91C_PIOA_PDR = AT91C_PA17_TXD0 | AT91C_PA18_RXD0;
  72         *AT91C_PMC_PCER |= 1 << AT91C_ID_USART0;        /* enable clock */
  73 #endif
  74 #ifdef CONFIG_USART1
  75         *AT91C_PIOB_PDR = AT91C_PB21_TXD1 | AT91C_PB20_RXD1;
  76         *AT91C_PMC_PCER |= 1 << AT91C_ID_USART1;        /* enable clock */
  77 #endif
  78         serial_setbrg ();
  79
  80         us->US_CR = AT91C_US_RSTRX | AT91C_US_RSTTX;
  81         us->US_CR = AT91C_US_RXEN | AT91C_US_TXEN;
  82         us->US_MR =
  83                 (AT91C_US_CLKS_CLOCK | AT91C_US_CHRL_8_BITS |
  84                  AT91C_US_PAR_NONE | AT91C_US_NBSTOP_1_BIT);
  85         us->US_IMR = ~0ul;
  86         return (0);
  87 }
  88
  89 void serial_putc (const char c)
  90 {
  91         if (c == '\n')
  92                 serial_putc ('\r');
  93         while ((us->US_CSR & AT91C_US_TXRDY) == 0);
  94         us->US_THR = c;
  95 }
  96
  97 void serial_puts (const char *s)
  98 {
  99         while (*s) {
 100                 serial_putc (*s++);
 101         }
 102 }
 103
 104 int serial_getc (void)
 105 {
 106         while ((us->US_CSR & AT91C_US_RXRDY) == 0);
 107         return us->US_RHR;
 108 }
 109
 110 int serial_tstc (void)
 111 {
 112         return ((us->US_CSR & AT91C_US_RXRDY) == AT91C_US_RXRDY);
 113 }