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