arch/m68k/atari/debug.c

   1 /*
   2  * linux/arch/m68k/atari/debug.c
   3  *
   4  * Atari debugging and serial console stuff
   5  *
   6  * Assembled of parts of former atari/config.c 97-12-18 by Roman Hodek
   7  *
   8  * This file is subject to the terms and conditions of the GNU General Public
   9  * License.  See the file COPYING in the main directory of this archive
  10  * for more details.
  11  */
  12
  13 #include <linux/types.h>
  14 #include <linux/tty.h>
  15 #include <linux/console.h>
  16 #include <linux/init.h>
  17 #include <linux/delay.h>
  18
  19 #include <asm/atarihw.h>
  20 #include <asm/atariints.h>
  21
  22 /* Flag that Modem1 port is already initialized and used */
  23 int atari_MFP_init_done;
  24 /* Flag that Modem1 port is already initialized and used */
  25 int atari_SCC_init_done;
  26 /* Can be set somewhere, if a SCC master reset has already be done and should
  27  * not be repeated; used by kgdb */
  28 int atari_SCC_reset_done;
  29
  30 static struct console atari_console_driver = {
  31         .name   = "debug",
  32         .flags  = CON_PRINTBUFFER,
  33         .index  = -1,
  34 };
  35
  36
  37 static inline void ata_mfp_out(char c)
  38 {
  39         while (!(mfp.trn_stat & 0x80))  /* wait for tx buf empty */
  40                 barrier();
  41         mfp.usart_dta = c;
  42 }
  43
  44 void atari_mfp_console_write(struct console *co, const char *str,
  45                              unsigned int count)
  46 {
  47         while (count--) {
  48                 if (*str == '\n')
  49                         ata_mfp_out('\r');
  50                 ata_mfp_out(*str++);
  51         }
  52 }
  53
  54 static inline void ata_scc_out(char c)
  55 {
  56         do {
  57                 MFPDELAY();
  58         } while (!(scc.cha_b_ctrl & 0x04)); /* wait for tx buf empty */
  59         MFPDELAY();
  60         scc.cha_b_data = c;
  61 }
  62
  63 void atari_scc_console_write(struct console *co, const char *str,
  64                              unsigned int count)
  65 {
  66         while (count--) {
  67                 if (*str == '\n')
  68                         ata_scc_out('\r');
  69                 ata_scc_out(*str++);
  70         }
  71 }
  72
  73 static inline void ata_midi_out(char c)
  74 {
  75         while (!(acia.mid_ctrl & ACIA_TDRE))    /* wait for tx buf empty */
  76                 barrier();
  77         acia.mid_data = c;
  78 }
  79
  80 void atari_midi_console_write(struct console *co, const char *str,
  81                               unsigned int count)
  82 {
  83         while (count--) {
  84                 if (*str == '\n')
  85                         ata_midi_out('\r');
  86                 ata_midi_out(*str++);
  87         }
  88 }
  89
  90 static int ata_par_out(char c)
  91 {
  92         unsigned char tmp;
  93         /* This a some-seconds timeout in case no printer is connected */
  94         unsigned long i = loops_per_jiffy > 1 ? loops_per_jiffy : 10000000/HZ;
  95
  96         while ((mfp.par_dt_reg & 1) && --i) /* wait for BUSY == L */
  97                 ;
  98         if (!i)
  99                 return 0;
 100
 101         sound_ym.rd_data_reg_sel = 15;  /* select port B */
 102         sound_ym.wd_data = c;           /* put char onto port */
 103         sound_ym.rd_data_reg_sel = 14;  /* select port A */
 104         tmp = sound_ym.rd_data_reg_sel;
 105         sound_ym.wd_data = tmp & ~0x20; /* set strobe L */
 106         MFPDELAY();                     /* wait a bit */
 107         sound_ym.wd_data = tmp | 0x20;  /* set strobe H */
 108         return 1;
 109 }
 110
 111 static void atari_par_console_write(struct console *co, const char *str,
 112                                     unsigned int count)
 113 {
 114         static int printer_present = 1;
 115
 116         if (!printer_present)
 117                 return;
 118
 119         while (count--) {
 120                 if (*str == '\n') {
 121                         if (!ata_par_out('\r')) {
 122                                 printer_present = 0;
 123                                 return;
 124                         }
 125                 }
 126                 if (!ata_par_out(*str++)) {
 127                         printer_present = 0;
 128                         return;
 129                 }
 130         }
 131 }
 132
 133 #ifdef CONFIG_SERIAL_CONSOLE
 134 int atari_mfp_console_wait_key(struct console *co)
 135 {
 136         while (!(mfp.rcv_stat & 0x80))  /* wait for rx buf filled */
 137                 barrier();
 138         return mfp.usart_dta;
 139 }
 140
 141 int atari_scc_console_wait_key(struct console *co)
 142 {
 143         do {
 144                 MFPDELAY();
 145         } while (!(scc.cha_b_ctrl & 0x01)); /* wait for rx buf filled */
 146         MFPDELAY();
 147         return scc.cha_b_data;
 148 }
 149
 150 int atari_midi_console_wait_key(struct console *co)
 151 {
 152         while (!(acia.mid_ctrl & ACIA_RDRF)) /* wait for rx buf filled */
 153                 barrier();
 154         return acia.mid_data;
 155 }
 156 #endif
 157
 158 /*
 159  * The following two functions do a quick'n'dirty initialization of the MFP or
 160  * SCC serial ports. They're used by the debugging interface, kgdb, and the
 161  * serial console code.
 162  */
 163 #ifndef CONFIG_SERIAL_CONSOLE
 164 static void __init atari_init_mfp_port(int cflag)
 165 #else
 166 void atari_init_mfp_port(int cflag)
 167 #endif
 168 {
 169         /*
 170          * timer values for 1200...115200 bps; > 38400 select 110, 134, or 150
 171          * bps, resp., and work only correct if there's a RSVE or RSSPEED
 172          */
 173         static int baud_table[9] = { 16, 11, 8, 4, 2, 1, 175, 143, 128 };
 174         int baud = cflag & CBAUD;
 175         int parity = (cflag & PARENB) ? ((cflag & PARODD) ? 0x04 : 0x06) : 0;
 176         int csize = ((cflag & CSIZE) == CS7) ? 0x20 : 0x00;
 177
 178         if (cflag & CBAUDEX)
 179                 baud += B38400;
 180         if (baud < B1200 || baud > B38400+2)
 181                 baud = B9600;           /* use default 9600bps for non-implemented rates */
 182         baud -= B1200;                  /* baud_table[] starts at 1200bps */
 183
 184         mfp.trn_stat &= ~0x01;          /* disable TX */
 185         mfp.usart_ctr = parity | csize | 0x88; /* 1:16 clk mode, 1 stop bit */
 186         mfp.tim_ct_cd &= 0x70;          /* stop timer D */
 187         mfp.tim_dt_d = baud_table[baud];
 188         mfp.tim_ct_cd |= 0x01;          /* start timer D, 1:4 */
 189         mfp.trn_stat |= 0x01;           /* enable TX */
 190
 191         atari_MFP_init_done = 1;
 192 }
 193
 194 #define SCC_WRITE(reg, val)                             \
 195         do {                                            \
 196                 scc.cha_b_ctrl = (reg);                 \
 197                 MFPDELAY();                             \
 198                 scc.cha_b_ctrl = (val);                 \
 199                 MFPDELAY();                             \
 200         } while (0)
 201
 202 /* loops_per_jiffy isn't initialized yet, so we can't use udelay(). This does a
 203  * delay of ~ 60us. */
 204 #define LONG_DELAY()                                    \
 205         do {                                            \
 206                 int i;                                  \
 207                 for (i = 100; i > 0; --i)               \
 208                         MFPDELAY();                     \
 209         } while (0)
 210
 211 #ifndef CONFIG_SERIAL_CONSOLE
 212 static void __init atari_init_scc_port(int cflag)
 213 #else
 214 void atari_init_scc_port(int cflag)
 215 #endif
 216 {
 217         extern int atari_SCC_reset_done;
 218         static int clksrc_table[9] =
 219                 /* reg 11: 0x50 = BRG, 0x00 = RTxC, 0x28 = TRxC */
 220                 { 0x50, 0x50, 0x50, 0x50, 0x50, 0x50, 0x50, 0x00, 0x00 };
 221         static int brgsrc_table[9] =
 222                 /* reg 14: 0 = RTxC, 2 = PCLK */
 223                 { 2, 2, 2, 2, 2, 2, 0, 2, 2 };
 224         static int clkmode_table[9] =
 225                 /* reg 4: 0x40 = x16, 0x80 = x32, 0xc0 = x64 */
 226                 { 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0xc0, 0x80 };
 227         static int div_table[9] =
 228                 /* reg12 (BRG low) */
 229                 { 208, 138, 103, 50, 24, 11, 1, 0, 0 };
 230
 231         int baud = cflag & CBAUD;
 232         int clksrc, clkmode, div, reg3, reg5;
 233
 234         if (cflag & CBAUDEX)
 235                 baud += B38400;
 236         if (baud < B1200 || baud > B38400+2)
 237                 baud = B9600;           /* use default 9600bps for non-implemented rates */
 238         baud -= B1200;                  /* tables starts at 1200bps */
 239
 240         clksrc  = clksrc_table[baud];
 241         clkmode = clkmode_table[baud];
 242         div     = div_table[baud];
 243         if (ATARIHW_PRESENT(TT_MFP) && baud >= 6) {
 244                 /* special treatment for TT, where rates >= 38400 are done via TRxC */
 245                 clksrc = 0x28;          /* TRxC */
 246                 clkmode = baud == 6 ? 0xc0 :
 247                           baud == 7 ? 0x80 : /* really 76800bps */
 248                                       0x40;  /* really 153600bps */
 249                 div = 0;
 250         }
 251
 252         reg3 = (cflag & CSIZE) == CS8 ? 0xc0 : 0x40;
 253         reg5 = (cflag & CSIZE) == CS8 ? 0x60 : 0x20 | 0x82 /* assert DTR/RTS */;
 254
 255         (void)scc.cha_b_ctrl;           /* reset reg pointer */
 256         SCC_WRITE(9, 0xc0);             /* reset */
 257         LONG_DELAY();                   /* extra delay after WR9 access */
 258         SCC_WRITE(4, (cflag & PARENB) ? ((cflag & PARODD) ? 0x01 : 0x03)
 259                                       : 0 | 0x04 /* 1 stopbit */ | clkmode);
 260         SCC_WRITE(3, reg3);
 261         SCC_WRITE(5, reg5);
 262         SCC_WRITE(9, 0);                /* no interrupts */
 263         LONG_DELAY();                   /* extra delay after WR9 access */
 264         SCC_WRITE(10, 0);               /* NRZ mode */
 265         SCC_WRITE(11, clksrc);          /* main clock source */
 266         SCC_WRITE(12, div);             /* BRG value */
 267         SCC_WRITE(13, 0);               /* BRG high byte */
 268         SCC_WRITE(14, brgsrc_table[baud]);
 269         SCC_WRITE(14, brgsrc_table[baud] | (div ? 1 : 0));
 270         SCC_WRITE(3, reg3 | 1);
 271         SCC_WRITE(5, reg5 | 8);
 272
 273         atari_SCC_reset_done = 1;
 274         atari_SCC_init_done = 1;
 275 }
 276
 277 #ifndef CONFIG_SERIAL_CONSOLE
 278 static void __init atari_init_midi_port(int cflag)
 279 #else
 280 void atari_init_midi_port(int cflag)
 281 #endif
 282 {
 283         int baud = cflag & CBAUD;
 284         int csize = ((cflag & CSIZE) == CS8) ? 0x10 : 0x00;
 285         /* warning 7N1 isn't possible! (instead 7O2 is used...) */
 286         int parity = (cflag & PARENB) ? ((cflag & PARODD) ? 0x0c : 0x08) : 0x04;
 287         int div;
 288
 289         /* 4800 selects 7812.5, 115200 selects 500000, all other (incl. 9600 as
 290          * default) the standard MIDI speed 31250. */
 291         if (cflag & CBAUDEX)
 292                 baud += B38400;
 293         if (baud == B4800)
 294                 div = ACIA_DIV64;       /* really 7812.5 bps */
 295         else if (baud == B38400+2 /* 115200 */)
 296                 div = ACIA_DIV1;        /* really 500 kbps (does that work??) */
 297         else
 298                 div = ACIA_DIV16;       /* 31250 bps, standard for MIDI */
 299
 300         /* RTS low, ints disabled */
 301         acia.mid_ctrl = div | csize | parity |
 302                     ((atari_switches & ATARI_SWITCH_MIDI) ?
 303                      ACIA_RHTID : ACIA_RLTID);
 304 }
 305
 306 static int __init atari_debug_setup(char *arg)
 307 {
 308         if (!MACH_IS_ATARI)
 309                 return 0;
 310
 311         if (!strcmp(arg, "ser"))
 312                 /* defaults to ser2 for a Falcon and ser1 otherwise */
 313                 arg = MACH_IS_FALCON ? "ser2" : "ser1";
 314
 315         if (!strcmp(arg, "ser1")) {
 316                 /* ST-MFP Modem1 serial port */
 317                 atari_init_mfp_port(B9600|CS8);
 318                 atari_console_driver.write = atari_mfp_console_write;
 319         } else if (!strcmp(arg, "ser2")) {
 320                 /* SCC Modem2 serial port */
 321                 atari_init_scc_port(B9600|CS8);
 322                 atari_console_driver.write = atari_scc_console_write;
 323         } else if (!strcmp(arg, "midi")) {
 324                 /* MIDI port */
 325                 atari_init_midi_port(B9600|CS8);
 326                 atari_console_driver.write = atari_midi_console_write;
 327         } else if (!strcmp(arg, "par")) {
 328                 /* parallel printer */
 329                 atari_turnoff_irq(IRQ_MFP_BUSY); /* avoid ints */
 330                 sound_ym.rd_data_reg_sel = 7;   /* select mixer control */
 331                 sound_ym.wd_data = 0xff;        /* sound off, ports are output */
 332                 sound_ym.rd_data_reg_sel = 15;  /* select port B */
 333                 sound_ym.wd_data = 0;           /* no char */
 334                 sound_ym.rd_data_reg_sel = 14;  /* select port A */
 335                 sound_ym.wd_data = sound_ym.rd_data_reg_sel | 0x20; /* strobe H */
 336                 atari_console_driver.write = atari_par_console_write;
 337         }
 338         if (atari_console_driver.write)
 339                 register_console(&atari_console_driver);
 340
 341         return 0;
 342 }
 343
 344 early_param("debug", atari_debug_setup);