arch/m68k/mac/debug.c

   1 /*
   2  * linux/arch/m68k/mac/debug.c
   3  *
   4  * Shamelessly stolen (SCC code and general framework) from:
   5  *
   6  * linux/arch/m68k/atari/debug.c
   7  *
   8  * Atari debugging and serial console stuff
   9  *
  10  * Assembled of parts of former atari/config.c 97-12-18 by Roman Hodek
  11  *
  12  * This file is subject to the terms and conditions of the GNU General Public
  13  * License.  See the file COPYING in the main directory of this archive
  14  * for more details.
  15  */
  16
  17 #include <linux/config.h>
  18 #include <linux/types.h>
  19 #include <linux/sched.h>
  20 #include <linux/tty.h>
  21 #include <linux/console.h>
  22 #include <linux/init.h>
  23 #include <linux/delay.h>
  24
  25 #define BOOTINFO_COMPAT_1_0
  26 #include <asm/setup.h>
  27 #include <asm/bootinfo.h>
  28 #include <asm/machw.h>
  29 #include <asm/macints.h>
  30
  31 extern char m68k_debug_device[];
  32
  33 extern struct compat_bootinfo compat_boot_info;
  34
  35 extern unsigned long mac_videobase;
  36 extern unsigned long mac_videodepth;
  37 extern unsigned long mac_rowbytes;
  38
  39 extern void mac_serial_print(const char *);
  40
  41 #define DEBUG_HEADS
  42 #undef DEBUG_SCREEN
  43 #define DEBUG_SERIAL
  44
  45 /*
  46  * These two auxiliary debug functions should go away ASAP. Only usage:
  47  * before the console output is up (after head.S come some other crucial
  48  * setup routines :-) it permits writing 'data' to the screen as bit patterns
  49  * (good luck reading those). Helped to figure that the bootinfo contained
  50  * garbage data on the amount and size of memory chunks ...
  51  *
  52  * The 'pos' argument now simply means 'linefeed after print' ...
  53  */
  54
  55 #ifdef DEBUG_SCREEN
  56 static int peng=0, line=0;
  57 #endif
  58
  59 void mac_debugging_short(int pos, short num)
  60 {
  61 #ifdef DEBUG_SCREEN
  62         unsigned char *pengoffset;
  63         unsigned char *pptr;
  64         int i;
  65 #endif
  66
  67 #ifdef DEBUG_SERIAL
  68         printk("debug: %d !\n", num);
  69 #endif
  70
  71 #ifdef DEBUG_SCREEN
  72         if (!MACH_IS_MAC) {
  73                 /* printk("debug: %d !\n", num); */
  74                 return;
  75         }
  76
  77         /* calculate current offset */
  78         pengoffset=(unsigned char *)(mac_videobase+(150+line*2)*mac_rowbytes)
  79                     +80*peng;
  80
  81         pptr=pengoffset;
  82
  83         for(i=0;i<8*sizeof(short);i++) /* # of bits */
  84         {
  85                 /*        value        mask for bit i, reverse order */
  86                 *pptr++ = (num & ( 1 << (8*sizeof(short)-i-1) ) ? 0xFF : 0x00);
  87         }
  88
  89         peng++;
  90
  91         if (pos) {
  92                 line++;
  93                 peng = 0;
  94         }
  95 #endif
  96 }
  97
  98 void mac_debugging_long(int pos, long addr)
  99 {
 100 #ifdef DEBUG_SCREEN
 101         unsigned char *pengoffset;
 102         unsigned char *pptr;
 103         int i;
 104 #endif
 105
 106 #ifdef DEBUG_SERIAL
 107         printk("debug: #%ld !\n", addr);
 108 #endif
 109
 110 #ifdef DEBUG_SCREEN
 111         if (!MACH_IS_MAC) {
 112                 /* printk("debug: #%ld !\n", addr); */
 113                 return;
 114         }
 115
 116         pengoffset=(unsigned char *)(mac_videobase+(150+line*2)*mac_rowbytes)
 117                     +80*peng;
 118
 119         pptr=pengoffset;
 120
 121         for(i=0;i<8*sizeof(long);i++) /* # of bits */
 122         {
 123                 *pptr++ = (addr & ( 1 << (8*sizeof(long)-i-1) ) ? 0xFF : 0x00);
 124         }
 125
 126         peng++;
 127
 128         if (pos) {
 129                 line++;
 130                 peng = 0;
 131         }
 132 #endif
 133 }
 134
 135 #ifdef DEBUG_SERIAL
 136 /*
 137  * TODO: serial debug code
 138  */
 139
 140 struct mac_SCC
 141  {
 142   u_char cha_b_ctrl;
 143   u_char char_dummy1;
 144   u_char cha_a_ctrl;
 145   u_char char_dummy2;
 146   u_char cha_b_data;
 147   u_char char_dummy3;
 148   u_char cha_a_data;
 149  };
 150
 151 # define scc (*((volatile struct mac_SCC*)mac_bi_data.sccbase))
 152
 153 /* Flag that serial port is already initialized and used */
 154 int mac_SCC_init_done;
 155 /* Can be set somewhere, if a SCC master reset has already be done and should
 156  * not be repeated; used by kgdb */
 157 int mac_SCC_reset_done;
 158
 159 static int scc_port = -1;
 160
 161 static struct console mac_console_driver = {
 162         .name =         "debug",
 163         .flags =        CON_PRINTBUFFER,
 164         .index =        -1,
 165 };
 166
 167 /*
 168  * Crude hack to get console output to the screen before the framebuffer
 169  * is initialized (happens a lot later in 2.1!).
 170  * We just use the console routines declared in head.S, this will interfere
 171  * with regular framebuffer console output and should be used exclusively
 172  * to debug kernel problems manifesting before framebuffer init (aka WSOD)
 173  *
 174  * To keep this hack from interfering with the regular console driver, either
 175  * deregister this driver before/on framebuffer console init, or silence this
 176  * function after the fbcon driver is running (will lose console messages!?).
 177  * To debug real early bugs, need to write a 'mac_register_console_hack()'
 178  * that is called from start_kernel() before setup_arch() and just registers
 179  * this driver if Mac.
 180  */
 181
 182 void mac_debug_console_write (struct console *co, const char *str,
 183                               unsigned int count)
 184 {
 185         mac_serial_print(str);
 186 }
 187
 188
 189
 190 /* Mac: loops_per_jiffy min. 19000 ^= .5 us; MFPDELAY was 0.6 us*/
 191
 192 #define uSEC 1
 193
 194 static inline void mac_sccb_out (char c)
 195 {
 196     int i;
 197     do {
 198         for( i = uSEC; i > 0; --i )
 199                 barrier();
 200     } while (!(scc.cha_b_ctrl & 0x04)); /* wait for tx buf empty */
 201     for( i = uSEC; i > 0; --i )
 202         barrier();
 203     scc.cha_b_data = c;
 204 }
 205
 206 static inline void mac_scca_out (char c)
 207 {
 208     int i;
 209     do {
 210         for( i = uSEC; i > 0; --i )
 211                 barrier();
 212     } while (!(scc.cha_a_ctrl & 0x04)); /* wait for tx buf empty */
 213     for( i = uSEC; i > 0; --i )
 214         barrier();
 215     scc.cha_a_data = c;
 216 }
 217
 218 void mac_sccb_console_write (struct console *co, const char *str,
 219                               unsigned int count)
 220 {
 221     while (count--) {
 222         if (*str == '\n')
 223             mac_sccb_out( '\r' );
 224         mac_sccb_out( *str++ );
 225     }
 226 }
 227
 228 void mac_scca_console_write (struct console *co, const char *str,
 229                               unsigned int count)
 230 {
 231     while (count--) {
 232         if (*str == '\n')
 233             mac_scca_out( '\r' );
 234         mac_scca_out( *str++ );
 235     }
 236 }
 237
 238
 239 /* The following two functions do a quick'n'dirty initialization of the MFP or
 240  * SCC serial ports. They're used by the debugging interface, kgdb, and the
 241  * serial console code. */
 242 #define SCCB_WRITE(reg,val)                             \
 243     do {                                                \
 244         int i;                                          \
 245         scc.cha_b_ctrl = (reg);                         \
 246         for( i = uSEC; i > 0; --i )                     \
 247                 barrier();                              \
 248         scc.cha_b_ctrl = (val);                         \
 249         for( i = uSEC; i > 0; --i )                     \
 250                 barrier();                              \
 251     } while(0)
 252
 253 #define SCCA_WRITE(reg,val)                             \
 254     do {                                                \
 255         int i;                                          \
 256         scc.cha_a_ctrl = (reg);                         \
 257         for( i = uSEC; i > 0; --i )                     \
 258                 barrier();                              \
 259         scc.cha_a_ctrl = (val);                         \
 260         for( i = uSEC; i > 0; --i )                     \
 261                 barrier();                              \
 262     } while(0)
 263
 264 /* loops_per_jiffy isn't initialized yet, so we can't use udelay(). This does a
 265  * delay of ~ 60us. */
 266 /* Mac: loops_per_jiffy min. 19000 ^= .5 us; MFPDELAY was 0.6 us*/
 267 #define LONG_DELAY()                            \
 268     do {                                        \
 269         int i;                                  \
 270         for( i = 60*uSEC; i > 0; --i )          \
 271             barrier();                          \
 272     } while(0)
 273
 274 #ifndef CONFIG_SERIAL_CONSOLE
 275 static void __init mac_init_scc_port( int cflag, int port )
 276 #else
 277 void mac_init_scc_port( int cflag, int port )
 278 #endif
 279 {
 280         extern int mac_SCC_reset_done;
 281
 282         /*
 283          * baud rates: 1200, 1800, 2400, 4800, 9600, 19.2k, 38.4k, 57.6k, 115.2k
 284          */
 285
 286         static int clksrc_table[9] =
 287                 /* reg 11: 0x50 = BRG, 0x00 = RTxC, 0x28 = TRxC */
 288                 { 0x50, 0x50, 0x50, 0x50, 0x50, 0x50, 0x50, 0x00, 0x00 };
 289         static int clkmode_table[9] =
 290                 /* reg 4: 0x40 = x16, 0x80 = x32, 0xc0 = x64 */
 291                 { 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0xc0, 0x80 };
 292         static int div_table[9] =
 293                 /* reg12 (BRG low) */
 294                 { 94, 62, 46, 22, 10, 4, 1, 0, 0 };
 295
 296     int baud = cflag & CBAUD;
 297     int clksrc, clkmode, div, reg3, reg5;
 298
 299     if (cflag & CBAUDEX)
 300         baud += B38400;
 301     if (baud < B1200 || baud > B38400+2)
 302         baud = B9600; /* use default 9600bps for non-implemented rates */
 303     baud -= B1200; /* tables starts at 1200bps */
 304
 305     clksrc  = clksrc_table[baud];
 306     clkmode = clkmode_table[baud];
 307     div     = div_table[baud];
 308
 309     reg3 = (((cflag & CSIZE) == CS8) ? 0xc0 : 0x40);
 310     reg5 = (((cflag & CSIZE) == CS8) ? 0x60 : 0x20) | 0x82 /* assert DTR/RTS */;
 311
 312     if (port == 1) {
 313             (void)scc.cha_b_ctrl;       /* reset reg pointer */
 314             SCCB_WRITE( 9, 0xc0 );      /* reset */
 315             LONG_DELAY();               /* extra delay after WR9 access */
 316             SCCB_WRITE( 4, (cflag & PARENB) ? ((cflag & PARODD) ? 0x01 : 0x03) : 0 |
 317                           0x04 /* 1 stopbit */ |
 318                           clkmode );
 319             SCCB_WRITE( 3, reg3 );
 320             SCCB_WRITE( 5, reg5 );
 321             SCCB_WRITE( 9, 0 );         /* no interrupts */
 322             LONG_DELAY();               /* extra delay after WR9 access */
 323             SCCB_WRITE( 10, 0 );        /* NRZ mode */
 324             SCCB_WRITE( 11, clksrc );   /* main clock source */
 325             SCCB_WRITE( 12, div );      /* BRG value */
 326             SCCB_WRITE( 13, 0 );                /* BRG high byte */
 327             SCCB_WRITE( 14, 1 );
 328             SCCB_WRITE( 3, reg3 | 1 );
 329             SCCB_WRITE( 5, reg5 | 8 );
 330     } else if (port == 0) {
 331             (void)scc.cha_a_ctrl;       /* reset reg pointer */
 332             SCCA_WRITE( 9, 0xc0 );      /* reset */
 333             LONG_DELAY();               /* extra delay after WR9 access */
 334             SCCA_WRITE( 4, (cflag & PARENB) ? ((cflag & PARODD) ? 0x01 : 0x03) : 0 |
 335                           0x04 /* 1 stopbit */ |
 336                           clkmode );
 337             SCCA_WRITE( 3, reg3 );
 338             SCCA_WRITE( 5, reg5 );
 339             SCCA_WRITE( 9, 0 );         /* no interrupts */
 340             LONG_DELAY();               /* extra delay after WR9 access */
 341             SCCA_WRITE( 10, 0 );        /* NRZ mode */
 342             SCCA_WRITE( 11, clksrc );   /* main clock source */
 343             SCCA_WRITE( 12, div );      /* BRG value */
 344             SCCA_WRITE( 13, 0 );                /* BRG high byte */
 345             SCCA_WRITE( 14, 1 );
 346             SCCA_WRITE( 3, reg3 | 1 );
 347             SCCA_WRITE( 5, reg5 | 8 );
 348     }
 349
 350     mac_SCC_reset_done = 1;
 351     mac_SCC_init_done = 1;
 352 }
 353 #endif /* DEBUG_SERIAL */
 354
 355 void mac_init_scca_port( int cflag )
 356 {
 357         mac_init_scc_port(cflag, 0);
 358 }
 359
 360 void mac_init_sccb_port( int cflag )
 361 {
 362         mac_init_scc_port(cflag, 1);
 363 }
 364
 365 void __init mac_debug_init(void)
 366 {
 367 #ifdef DEBUG_SERIAL
 368     if (   !strcmp( m68k_debug_device, "ser"  )
 369         || !strcmp( m68k_debug_device, "ser1" )) {
 370         /* Mac modem port */
 371         mac_init_scc_port( B9600|CS8, 0 );
 372         mac_console_driver.write = mac_scca_console_write;
 373         scc_port = 0;
 374     }
 375     else if (!strcmp( m68k_debug_device, "ser2" )) {
 376         /* Mac printer port */
 377         mac_init_scc_port( B9600|CS8, 1 );
 378         mac_console_driver.write = mac_sccb_console_write;
 379         scc_port = 1;
 380     }
 381 #endif
 382 #ifdef DEBUG_HEADS
 383     if (   !strcmp( m68k_debug_device, "scn"  )
 384         || !strcmp( m68k_debug_device, "con" )) {
 385         /* display, using head.S console routines */
 386         mac_console_driver.write = mac_debug_console_write;
 387     }
 388 #endif
 389     if (mac_console_driver.write)
 390         register_console(&mac_console_driver);
 391 }
 392
 393 /*
 394  * Local variables:
 395  *  c-indent-level: 4
 396  *  tab-width: 8
 397  * End:
 398  */