drivers/serial/serial_xuartlite.c

   1 /*
   2  * (C) Copyright 2008 Michal Simek <monstr@monstr.eu>
   3  * Clean driver and add xilinx constant from header file
   4  *
   5  * (C) Copyright 2004 Atmark Techno, Inc.
   6  * Yasushi SHOJI <yashi@atmark-techno.com>
   7  *
   8  * See file CREDITS for list of people who contributed to this
   9  * project.
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public License as
  13  * published by the Free Software Foundation; either version 2 of
  14  * the License, or (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  24  * MA 02111-1307 USA
  25  */
  26
  27 #include <config.h>
  28 #include <asm/io.h>
  29
  30 #ifdef  CONFIG_XILINX_UARTLITE
  31
  32 #define RX_FIFO_OFFSET          0 /* receive FIFO, read only */
  33 #define TX_FIFO_OFFSET          4 /* transmit FIFO, write only */
  34 #define STATUS_REG_OFFSET       8 /* status register, read only */
  35
  36 #define SR_TX_FIFO_FULL         0x08 /* transmit FIFO full */
  37 #define SR_RX_FIFO_VALID_DATA   0x01 /* data in receive FIFO */
  38 #define SR_RX_FIFO_FULL         0x02 /* receive FIFO full */
  39
  40 #define UARTLITE_STATUS         (CONFIG_SERIAL_BASE + STATUS_REG_OFFSET)
  41 #define UARTLITE_TX_FIFO        (CONFIG_SERIAL_BASE + TX_FIFO_OFFSET)
  42 #define UARTLITE_RX_FIFO        (CONFIG_SERIAL_BASE + RX_FIFO_OFFSET)
  43
  44 int serial_init(void)
  45 {
  46         /* FIXME: Nothing for now. We should initialize fifo, etc */
  47         return 0;
  48 }
  49
  50 void serial_setbrg(void)
  51 {
  52         /* FIXME: what's this for? */
  53 }
  54
  55 void serial_putc(const char c)
  56 {
  57         if (c == '\n')
  58                 serial_putc('\r');
  59         while (in_be32(UARTLITE_STATUS) & SR_TX_FIFO_FULL);
  60         out_be32(UARTLITE_TX_FIFO, (unsigned char) (c & 0xff));
  61 }
  62
  63 void serial_puts(const char * s)
  64 {
  65         while (*s) {
  66                 serial_putc(*s++);
  67         }
  68 }
  69
  70 int serial_getc(void)
  71 {
  72         while (!(in_be32(UARTLITE_STATUS) & SR_RX_FIFO_VALID_DATA));
  73         return in_be32(UARTLITE_RX_FIFO) & 0xff;
  74 }
  75
  76 int serial_tstc(void)
  77 {
  78         return (in_be32(UARTLITE_STATUS) & SR_RX_FIFO_VALID_DATA);
  79 }
  80
  81 #endif  /* CONFIG_MICROBLZE */