drivers/serial/serial_s3c24x0.c

   1 /*
   2  * (C) Copyright 2002
   3  * Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  *
  19  */
  20
  21 #include <common.h>
  22 #include <asm/arch/s3c24x0_cpu.h>
  23
  24 DECLARE_GLOBAL_DATA_PTR;
  25
  26 #ifdef CONFIG_SERIAL1
  27 #define UART_NR S3C24X0_UART0
  28
  29 #elif defined(CONFIG_SERIAL2)
  30 # if defined(CONFIG_TRAB)
  31 #  error "TRAB supports only CONFIG_SERIAL1"
  32 # endif
  33 #define UART_NR S3C24X0_UART1
  34
  35 #elif defined(CONFIG_SERIAL3)
  36 # if defined(CONFIG_TRAB)
  37 #  error "TRAB supports only CONFIG_SERIAL1"
  38 # endif
  39 #define UART_NR S3C24X0_UART2
  40
  41 #else
  42 #error "Bad: you didn't configure serial ..."
  43 #endif
  44
  45 #include <asm/io.h>
  46
  47 #if defined(CONFIG_SERIAL_MULTI)
  48 #include <serial.h>
  49
  50 /* Multi serial device functions */
  51 #define DECLARE_S3C_SERIAL_FUNCTIONS(port) \
  52         int s3serial##port##_init(void) \
  53         { \
  54                 return serial_init_dev(port); \
  55         } \
  56         void s3serial##port##_setbrg(void) \
  57         { \
  58                 serial_setbrg_dev(port); \
  59         } \
  60         int s3serial##port##_getc(void) \
  61         { \
  62                 return serial_getc_dev(port); \
  63         } \
  64         int s3serial##port##_tstc(void) \
  65         { \
  66                 return serial_tstc_dev(port); \
  67         } \
  68         void s3serial##port##_putc(const char c) \
  69         { \
  70                 serial_putc_dev(port, c); \
  71         } \
  72         void s3serial##port##_puts(const char *s) \
  73         { \
  74                 serial_puts_dev(port, s); \
  75         }
  76
  77 #define INIT_S3C_SERIAL_STRUCTURE(port, name, bus) { \
  78         name, \
  79         bus, \
  80         s3serial##port##_init, \
  81         s3serial##port##_setbrg, \
  82         s3serial##port##_getc, \
  83         s3serial##port##_tstc, \
  84         s3serial##port##_putc, \
  85         s3serial##port##_puts, \
  86 }
  87
  88 #endif /* CONFIG_SERIAL_MULTI */
  89
  90 #ifdef CONFIG_HWFLOW
  91 static int hwflow;
  92 #endif
  93
  94 void _serial_setbrg(const int dev_index)
  95 {
  96         struct s3c24x0_uart *uart = s3c24x0_get_base_uart(dev_index);
  97         unsigned int reg = 0;
  98         int i;
  99
 100         /* value is calculated so : (int)(PCLK/16./baudrate) -1 */
 101         reg = get_PCLK() / (16 * gd->baudrate) - 1;
 102
 103         writel(reg, &uart->UBRDIV);
 104         for (i = 0; i < 100; i++)
 105                 /* Delay */ ;
 106 }
 107
 108 #if defined(CONFIG_SERIAL_MULTI)
 109 static inline void serial_setbrg_dev(unsigned int dev_index)
 110 {
 111         _serial_setbrg(dev_index);
 112 }
 113 #else
 114 void serial_setbrg(void)
 115 {
 116         _serial_setbrg(UART_NR);
 117 }
 118 #endif
 119
 120
 121 /* Initialise the serial port. The settings are always 8 data bits, no parity,
 122  * 1 stop bit, no start bits.
 123  */
 124 static int serial_init_dev(const int dev_index)
 125 {
 126         struct s3c24x0_uart *uart = s3c24x0_get_base_uart(dev_index);
 127
 128 #ifdef CONFIG_HWFLOW
 129         hwflow = 0;     /* turned off by default */
 130 #endif
 131
 132         /* FIFO enable, Tx/Rx FIFO clear */
 133         writel(0x07, &uart->UFCON);
 134         writel(0x0, &uart->UMCON);
 135
 136         /* Normal,No parity,1 stop,8 bit */
 137         writel(0x3, &uart->ULCON);
 138         /*
 139          * tx=level,rx=edge,disable timeout int.,enable rx error int.,
 140          * normal,interrupt or polling
 141          */
 142         writel(0x245, &uart->UCON);
 143
 144 #ifdef CONFIG_HWFLOW
 145         writel(0x1, &uart->UMCON);      /* RTS up */
 146 #endif
 147
 148         /* FIXME: This is sooooooooooooooooooo ugly */
 149 #if defined(CONFIG_ARCH_GTA02_v1) || defined(CONFIG_ARCH_GTA02_v2)
 150         /* we need auto hw flow control on the gsm and gps port */
 151         if (dev_index == 0 || dev_index == 1)
 152                 writel(0x10, &uart->UMCON);
 153 #endif
 154         _serial_setbrg(dev_index);
 155
 156         return (0);
 157 }
 158
 159 #if !defined(CONFIG_SERIAL_MULTI)
 160 /* Initialise the serial port. The settings are always 8 data bits, no parity,
 161  * 1 stop bit, no start bits.
 162  */
 163 int serial_init(void)
 164 {
 165         return serial_init_dev(UART_NR);
 166 }
 167 #endif
 168
 169 /*
 170  * Read a single byte from the serial port. Returns 1 on success, 0
 171  * otherwise. When the function is succesfull, the character read is
 172  * written into its argument c.
 173  */
 174 int _serial_getc(const int dev_index)
 175 {
 176         struct s3c24x0_uart *uart = s3c24x0_get_base_uart(dev_index);
 177
 178         while (!(readl(&uart->UTRSTAT) & 0x1))
 179                 /* wait for character to arrive */ ;
 180
 181         return readb(&uart->URXH) & 0xff;
 182 }
 183
 184 #if defined(CONFIG_SERIAL_MULTI)
 185 static inline int serial_getc_dev(unsigned int dev_index)
 186 {
 187         return _serial_getc(dev_index);
 188 }
 189 #else
 190 int serial_getc(void)
 191 {
 192         return _serial_getc(UART_NR);
 193 }
 194 #endif
 195
 196 #ifdef CONFIG_HWFLOW
 197 int hwflow_onoff(int on)
 198 {
 199         switch (on) {
 200         case 0:
 201         default:
 202                 break;          /* return current */
 203         case 1:
 204                 hwflow = 1;     /* turn on */
 205                 break;
 206         case -1:
 207                 hwflow = 0;     /* turn off */
 208                 break;
 209         }
 210         return hwflow;
 211 }
 212 #endif
 213
 214 #ifdef CONFIG_MODEM_SUPPORT
 215 static int be_quiet = 0;
 216 void disable_putc(void)
 217 {
 218         be_quiet = 1;
 219 }
 220
 221 void enable_putc(void)
 222 {
 223         be_quiet = 0;
 224 }
 225 #endif
 226
 227
 228 /*
 229  * Output a single byte to the serial port.
 230  */
 231 void _serial_putc(const char c, const int dev_index)
 232 {
 233         struct s3c24x0_uart *uart = s3c24x0_get_base_uart(dev_index);
 234 #ifdef CONFIG_MODEM_SUPPORT
 235         if (be_quiet)
 236                 return;
 237 #endif
 238
 239         while (!(readl(&uart->UTRSTAT) & 0x2))
 240                 /* wait for room in the tx FIFO */ ;
 241
 242 #ifdef CONFIG_HWFLOW
 243         while (hwflow && !(readl(&uart->UMSTAT) & 0x1))
 244                 /* Wait for CTS up */ ;
 245 #endif
 246
 247         writeb(c, &uart->UTXH);
 248
 249         /* If \n, also do \r */
 250         if (c == '\n')
 251                 serial_putc('\r');
 252 }
 253
 254 #if defined(CONFIG_SERIAL_MULTI)
 255 static inline void serial_putc_dev(unsigned int dev_index, const char c)
 256 {
 257         _serial_putc(c, dev_index);
 258 }
 259 #else
 260 void serial_putc(const char c)
 261 {
 262         _serial_putc(c, UART_NR);
 263 }
 264 #endif
 265
 266
 267 /*
 268  * Test whether a character is in the RX buffer
 269  */
 270 int _serial_tstc(const int dev_index)
 271 {
 272         struct s3c24x0_uart *uart = s3c24x0_get_base_uart(dev_index);
 273
 274         return readl(&uart->UTRSTAT) & 0x1;
 275 }
 276
 277 #if defined(CONFIG_SERIAL_MULTI)
 278 static inline int serial_tstc_dev(unsigned int dev_index)
 279 {
 280         return _serial_tstc(dev_index);
 281 }
 282 #else
 283 int serial_tstc(void)
 284 {
 285         return _serial_tstc(UART_NR);
 286 }
 287 #endif
 288
 289 void _serial_puts(const char *s, const int dev_index)
 290 {
 291         while (*s) {
 292                 _serial_putc(*s++, dev_index);
 293         }
 294 }
 295
 296 #if defined(CONFIG_SERIAL_MULTI)
 297 static inline void serial_puts_dev(int dev_index, const char *s)
 298 {
 299         _serial_puts(s, dev_index);
 300 }
 301 #else
 302 void serial_puts(const char *s)
 303 {
 304         _serial_puts(s, UART_NR);
 305 }
 306 #endif
 307
 308 #if defined(CONFIG_SERIAL_MULTI)
 309 DECLARE_S3C_SERIAL_FUNCTIONS(0);
 310 struct serial_device s3c24xx_serial0_device =
 311 INIT_S3C_SERIAL_STRUCTURE(0, "s3ser0", "S3UART1");
 312 DECLARE_S3C_SERIAL_FUNCTIONS(1);
 313 struct serial_device s3c24xx_serial1_device =
 314 INIT_S3C_SERIAL_STRUCTURE(1, "s3ser1", "S3UART2");
 315 DECLARE_S3C_SERIAL_FUNCTIONS(2);
 316 struct serial_device s3c24xx_serial2_device =
 317 INIT_S3C_SERIAL_STRUCTURE(2, "s3ser2", "S3UART3");
 318 #endif /* CONFIG_SERIAL_MULTI */