drivers/serial/serial_netarm.c

   1 /*
   2  * Serial Port stuff - taken from Linux
   3  *
   4  * (C) Copyright 2002
   5  * MAZeT GmbH <www.mazet.de>
   6  * Stephan Linz <linz@mazet.de>, <linz@li-pro.net>
   7  *
   8  * (c) 2004
   9  * IMMS gGmbH <www.imms.de>
  10  * Thomas Elste <info@elste.org>
  11  *
  12  * See file CREDITS for list of people who contributed to this
  13  * project.
  14  *
  15  * This program is free software; you can redistribute it and/or modify
  16  * it under the terms of the GNU General Public License as published by
  17  * the Free Software Foundation; either version 2 of the License, or
  18  * (at your option) any later version.
  19  *
  20  * This program is distributed in the hope that it will be useful,
  21  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23  * GNU General Public License for more details.
  24  *
  25  * You should have received a copy of the GNU General Public License
  26  * along with this program; if not, write to the Free Software
  27  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  28  *
  29  */
  30
  31 #include <common.h>
  32 #include <asm/hardware.h>
  33
  34 DECLARE_GLOBAL_DATA_PTR;
  35
  36 #define PORTA   (*(volatile unsigned int *)(NETARM_GEN_MODULE_BASE + NETARM_GEN_PORTA))
  37 #if !defined(CONFIG_NETARM_NS7520)
  38 #define PORTB   (*(volatile unsigned int *)(NETARM_GEN_MODULE_BASE + NETARM_GEN_PORTB))
  39 #else
  40 #define PORTC   (*(volatile unsigned int *)(NETARM_GEN_MODULE_BASE + NETARM_GEN_PORTC))
  41 #endif
  42
  43 /* wait until transmitter is ready for another character */
  44 #define TXWAITRDY(registers)                                                    \
  45 {                                                                               \
  46         ulong tmo = get_timer(0) + 1 * CONFIG_SYS_HZ;                                   \
  47         while (((registers)->status_a & NETARM_SER_STATA_TX_RDY) == 0 ) {       \
  48                 if (get_timer(0) > tmo)                                         \
  49                         break;                                                  \
  50         }                                                                       \
  51 }
  52
  53
  54 #ifndef CONFIG_UART1_CONSOLE
  55 volatile netarm_serial_channel_t *serial_reg_ch1 = get_serial_channel(0);
  56 volatile netarm_serial_channel_t *serial_reg_ch2 = get_serial_channel(1);
  57 #else
  58 volatile netarm_serial_channel_t *serial_reg_ch1 = get_serial_channel(1);
  59 volatile netarm_serial_channel_t *serial_reg_ch2 = get_serial_channel(0);
  60 #endif
  61
  62 extern void _netarm_led_FAIL1(void);
  63
  64 /*
  65  * Setup both serial i/f with given baudrate
  66  */
  67 void serial_setbrg (void)
  68 {
  69         /* set 0 ... make sure pins are configured for serial */
  70 #if !defined(CONFIG_NETARM_NS7520)
  71         PORTA = PORTB =
  72                 NETARM_GEN_PORT_MODE (0xef) | NETARM_GEN_PORT_DIR (0xe0);
  73 #else
  74         PORTA = NETARM_GEN_PORT_MODE (0xef) | NETARM_GEN_PORT_DIR (0xe0);
  75         PORTC = NETARM_GEN_PORT_CSF (0xef) | NETARM_GEN_PORT_MODE (0xef) | NETARM_GEN_PORT_DIR (0xe0);
  76 #endif
  77
  78         /* first turn em off */
  79         serial_reg_ch1->ctrl_a = serial_reg_ch2->ctrl_a = 0;
  80
  81         /* clear match register, we don't need it */
  82         serial_reg_ch1->rx_match = serial_reg_ch2->rx_match = 0;
  83
  84         /* setup bit rate generator and rx buffer gap timer (1 byte only) */
  85         if ((gd->baudrate >= MIN_BAUD_RATE)
  86             && (gd->baudrate <= MAX_BAUD_RATE)) {
  87                 serial_reg_ch1->bitrate = serial_reg_ch2->bitrate =
  88                         NETARM_SER_BR_X16 (gd->baudrate);
  89                 serial_reg_ch1->rx_buf_timer = serial_reg_ch2->rx_buf_timer =
  90                         0;
  91                 serial_reg_ch1->rx_char_timer = serial_reg_ch2->rx_char_timer =
  92                         NETARM_SER_RXGAP (gd->baudrate);
  93         } else {
  94                 hang ();
  95         }
  96
  97         /* setup port mode */
  98         serial_reg_ch1->ctrl_b = serial_reg_ch2->ctrl_b =
  99                 ( NETARM_SER_CTLB_RCGT_EN |
 100                   NETARM_SER_CTLB_UART_MODE);
 101         serial_reg_ch1->ctrl_a = serial_reg_ch2->ctrl_a =
 102                 ( NETARM_SER_CTLA_ENABLE |
 103                   NETARM_SER_CTLA_P_NONE |
 104                   /* see errata */
 105                   NETARM_SER_CTLA_2STOP |
 106                   NETARM_SER_CTLA_8BITS |
 107                   NETARM_SER_CTLA_DTR_EN |
 108                   NETARM_SER_CTLA_RTS_EN);
 109 }
 110
 111
 112 /*
 113  * Initialise the serial port with the given baudrate. The settings
 114  * are always 8 data bits, no parity, 1 stop bit, no start bits.
 115  */
 116 int serial_init (void)
 117 {
 118         serial_setbrg ();
 119         return 0;
 120 }
 121
 122
 123 /*
 124  * Output a single byte to the serial port.
 125  */
 126 void serial_putc (const char c)
 127 {
 128         volatile unsigned char *fifo;
 129
 130         /* If \n, also do \r */
 131         if (c == '\n')
 132                 serial_putc ('\r');
 133
 134         fifo = (volatile unsigned char *) &(serial_reg_ch1->fifo);
 135         TXWAITRDY (serial_reg_ch1);
 136         *fifo = c;
 137 }
 138
 139 /*
 140  * Test of a single byte from the serial port. Returns 1 on success, 0
 141  * otherwise.
 142  */
 143 int serial_tstc(void)
 144 {
 145         return serial_reg_ch1->status_a & NETARM_SER_STATA_RX_RDY;
 146 }
 147
 148 /*
 149  * Read a single byte from the serial port. Returns 1 on success, 0
 150  * otherwise.
 151  */
 152 int serial_getc (void)
 153 {
 154         unsigned int ch_uint;
 155         volatile unsigned int *fifo;
 156         volatile unsigned char *fifo_char = NULL;
 157         int buf_count = 0;
 158
 159         while (!(serial_reg_ch1->status_a & NETARM_SER_STATA_RX_RDY))
 160                 /* NOP */ ;
 161
 162         fifo = (volatile unsigned int *) &(serial_reg_ch1->fifo);
 163         fifo_char = (unsigned char *) &ch_uint;
 164         ch_uint = *fifo;
 165
 166         buf_count = NETARM_SER_STATA_RXFDB (serial_reg_ch1->status_a);
 167         switch (buf_count) {
 168         case NETARM_SER_STATA_RXFDB_4BYTES:
 169                 buf_count = 4;
 170                 break;
 171         case NETARM_SER_STATA_RXFDB_3BYTES:
 172                 buf_count = 3;
 173                 break;
 174         case NETARM_SER_STATA_RXFDB_2BYTES:
 175                 buf_count = 2;
 176                 break;
 177         case NETARM_SER_STATA_RXFDB_1BYTES:
 178                 buf_count = 1;
 179                 break;
 180         default:
 181                 /* panic, be never here */
 182                 break;
 183         }
 184
 185         serial_reg_ch1->status_a |= NETARM_SER_STATA_RX_CLOSED;
 186
 187         return ch_uint & 0xff;
 188 }
 189
 190 void serial_puts (const char *s)
 191 {
 192         while (*s) {
 193                 serial_putc (*s++);
 194         }
 195 }