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MN10300: Fix interrupt mask alteration function call name in gdbstub
[~shefty/rdma-dev.git] / arch / mn10300 / kernel / gdb-stub.c
1 /* MN10300 GDB stub
2  *
3  * Originally written by Glenn Engel, Lake Stevens Instrument Division
4  *
5  * Contributed by HP Systems
6  *
7  * Modified for SPARC by Stu Grossman, Cygnus Support.
8  *
9  * Modified for Linux/MIPS (and MIPS in general) by Andreas Busse
10  * Send complaints, suggestions etc. to <andy@waldorf-gmbh.de>
11  *
12  * Copyright (C) 1995 Andreas Busse
13  *
14  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
15  * Modified for Linux/mn10300 by David Howells <dhowells@redhat.com>
16  */
17
18 /*
19  *  To enable debugger support, two things need to happen.  One, a
20  *  call to set_debug_traps() is necessary in order to allow any breakpoints
21  *  or error conditions to be properly intercepted and reported to gdb.
22  *  Two, a breakpoint needs to be generated to begin communication.  This
23  *  is most easily accomplished by a call to breakpoint().  Breakpoint()
24  *  simulates a breakpoint by executing a BREAK instruction.
25  *
26  *
27  *    The following gdb commands are supported:
28  *
29  * command          function                               Return value
30  *
31  *    g             return the value of the CPU registers  hex data or ENN
32  *    G             set the value of the CPU registers     OK or ENN
33  *
34  *    mAA..AA,LLLL  Read LLLL bytes at address AA..AA      hex data or ENN
35  *    MAA..AA,LLLL: Write LLLL bytes at address AA.AA      OK or ENN
36  *
37  *    c             Resume at current address              SNN   ( signal NN)
38  *    cAA..AA       Continue at address AA..AA             SNN
39  *
40  *    s             Step one instruction                   SNN
41  *    sAA..AA       Step one instruction from AA..AA       SNN
42  *
43  *    k             kill
44  *
45  *    ?             What was the last sigval ?             SNN   (signal NN)
46  *
47  *    bBB..BB       Set baud rate to BB..BB                OK or BNN, then sets
48  *                                                         baud rate
49  *
50  * All commands and responses are sent with a packet which includes a
51  * checksum.  A packet consists of
52  *
53  * $<packet info>#<checksum>.
54  *
55  * where
56  * <packet info> :: <characters representing the command or response>
57  * <checksum>    :: < two hex digits computed as modulo 256 sum of <packetinfo>>
58  *
59  * When a packet is received, it is first acknowledged with either '+' or '-'.
60  * '+' indicates a successful transfer.  '-' indicates a failed transfer.
61  *
62  * Example:
63  *
64  * Host:                  Reply:
65  * $m0,10#2a               +$00010203040506070809101112131415#42
66  *
67  *
68  *  ==============
69  *  MORE EXAMPLES:
70  *  ==============
71  *
72  *  For reference -- the following are the steps that one
73  *  company took (RidgeRun Inc) to get remote gdb debugging
74  *  going. In this scenario the host machine was a PC and the
75  *  target platform was a Galileo EVB64120A MIPS evaluation
76  *  board.
77  *
78  *  Step 1:
79  *  First download gdb-5.0.tar.gz from the internet.
80  *  and then build/install the package.
81  *
82  *  Example:
83  *    $ tar zxf gdb-5.0.tar.gz
84  *    $ cd gdb-5.0
85  *    $ ./configure --target=am33_2.0-linux-gnu
86  *    $ make
87  *    $ install
88  *    am33_2.0-linux-gnu-gdb
89  *
90  *  Step 2:
91  *  Configure linux for remote debugging and build it.
92  *
93  *  Example:
94  *    $ cd ~/linux
95  *    $ make menuconfig <go to "Kernel Hacking" and turn on remote debugging>
96  *    $ make dep; make vmlinux
97  *
98  *  Step 3:
99  *  Download the kernel to the remote target and start
100  *  the kernel running. It will promptly halt and wait
101  *  for the host gdb session to connect. It does this
102  *  since the "Kernel Hacking" option has defined
103  *  CONFIG_REMOTE_DEBUG which in turn enables your calls
104  *  to:
105  *     set_debug_traps();
106  *     breakpoint();
107  *
108  *  Step 4:
109  *  Start the gdb session on the host.
110  *
111  *  Example:
112  *    $ am33_2.0-linux-gnu-gdb vmlinux
113  *    (gdb) set remotebaud 115200
114  *    (gdb) target remote /dev/ttyS1
115  *    ...at this point you are connected to
116  *       the remote target and can use gdb
117  *       in the normal fasion. Setting
118  *       breakpoints, single stepping,
119  *       printing variables, etc.
120  *
121  */
122
123 #include <linux/string.h>
124 #include <linux/kernel.h>
125 #include <linux/signal.h>
126 #include <linux/sched.h>
127 #include <linux/mm.h>
128 #include <linux/console.h>
129 #include <linux/init.h>
130 #include <linux/bug.h>
131
132 #include <asm/pgtable.h>
133 #include <asm/system.h>
134 #include <asm/gdb-stub.h>
135 #include <asm/exceptions.h>
136 #include <asm/cacheflush.h>
137 #include <asm/serial-regs.h>
138 #include <asm/busctl-regs.h>
139 #include <unit/leds.h>
140 #include <unit/serial.h>
141
142 /* define to use F7F7 rather than FF which is subverted by JTAG debugger */
143 #undef GDBSTUB_USE_F7F7_AS_BREAKPOINT
144
145 /*
146  * BUFMAX defines the maximum number of characters in inbound/outbound buffers
147  * at least NUMREGBYTES*2 are needed for register packets
148  */
149 #define BUFMAX 2048
150
151 static const char gdbstub_banner[] =
152         "Linux/MN10300 GDB Stub (c) RedHat 2007\n";
153
154 u8      gdbstub_rx_buffer[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
155 u32     gdbstub_rx_inp;
156 u32     gdbstub_rx_outp;
157 u8      gdbstub_busy;
158 u8      gdbstub_rx_overflow;
159 u8      gdbstub_rx_unget;
160
161 static u8       gdbstub_flush_caches;
162 static char     input_buffer[BUFMAX];
163 static char     output_buffer[BUFMAX];
164 static char     trans_buffer[BUFMAX];
165
166 struct gdbstub_bkpt {
167         u8      *addr;          /* address of breakpoint */
168         u8      len;            /* size of breakpoint */
169         u8      origbytes[7];   /* original bytes */
170 };
171
172 static struct gdbstub_bkpt gdbstub_bkpts[256];
173
174 /*
175  * local prototypes
176  */
177 static void getpacket(char *buffer);
178 static int putpacket(char *buffer);
179 static int computeSignal(enum exception_code excep);
180 static int hex(unsigned char ch);
181 static int hexToInt(char **ptr, int *intValue);
182 static unsigned char *mem2hex(const void *mem, char *buf, int count,
183                               int may_fault);
184 static const char *hex2mem(const char *buf, void *_mem, int count,
185                            int may_fault);
186
187 /*
188  * Convert ch from a hex digit to an int
189  */
190 static int hex(unsigned char ch)
191 {
192         if (ch >= 'a' && ch <= 'f')
193                 return ch - 'a' + 10;
194         if (ch >= '0' && ch <= '9')
195                 return ch - '0';
196         if (ch >= 'A' && ch <= 'F')
197                 return ch - 'A' + 10;
198         return -1;
199 }
200
201 #ifdef CONFIG_GDBSTUB_DEBUGGING
202
203 void debug_to_serial(const char *p, int n)
204 {
205         __debug_to_serial(p, n);
206         /* gdbstub_console_write(NULL, p, n); */
207 }
208
209 void gdbstub_printk(const char *fmt, ...)
210 {
211         va_list args;
212         int len;
213
214         /* Emit the output into the temporary buffer */
215         va_start(args, fmt);
216         len = vsnprintf(trans_buffer, sizeof(trans_buffer), fmt, args);
217         va_end(args);
218         debug_to_serial(trans_buffer, len);
219 }
220
221 #endif
222
223 static inline char *gdbstub_strcpy(char *dst, const char *src)
224 {
225         int loop = 0;
226         while ((dst[loop] = src[loop]))
227                loop++;
228         return dst;
229 }
230
231 /*
232  * scan for the sequence $<data>#<checksum>
233  */
234 static void getpacket(char *buffer)
235 {
236         unsigned char checksum;
237         unsigned char xmitcsum;
238         unsigned char ch;
239         int count, i, ret, error;
240
241         for (;;) {
242                 /*
243                  * wait around for the start character,
244                  * ignore all other characters
245                  */
246                 do {
247                         gdbstub_io_rx_char(&ch, 0);
248                 } while (ch != '$');
249
250                 checksum = 0;
251                 xmitcsum = -1;
252                 count = 0;
253                 error = 0;
254
255                 /*
256                  * now, read until a # or end of buffer is found
257                  */
258                 while (count < BUFMAX) {
259                         ret = gdbstub_io_rx_char(&ch, 0);
260                         if (ret < 0)
261                                 error = ret;
262
263                         if (ch == '#')
264                                 break;
265                         checksum += ch;
266                         buffer[count] = ch;
267                         count++;
268                 }
269
270                 if (error == -EIO) {
271                         gdbstub_proto("### GDB Rx Error - Skipping packet"
272                                       " ###\n");
273                         gdbstub_proto("### GDB Tx NAK\n");
274                         gdbstub_io_tx_char('-');
275                         continue;
276                 }
277
278                 if (count >= BUFMAX || error)
279                         continue;
280
281                 buffer[count] = 0;
282
283                 /* read the checksum */
284                 ret = gdbstub_io_rx_char(&ch, 0);
285                 if (ret < 0)
286                         error = ret;
287                 xmitcsum = hex(ch) << 4;
288
289                 ret = gdbstub_io_rx_char(&ch, 0);
290                 if (ret < 0)
291                         error = ret;
292                 xmitcsum |= hex(ch);
293
294                 if (error) {
295                         if (error == -EIO)
296                                 gdbstub_io("### GDB Rx Error -"
297                                            " Skipping packet\n");
298                         gdbstub_io("### GDB Tx NAK\n");
299                         gdbstub_io_tx_char('-');
300                         continue;
301                 }
302
303                 /* check the checksum */
304                 if (checksum != xmitcsum) {
305                         gdbstub_io("### GDB Tx NAK\n");
306                         gdbstub_io_tx_char('-');        /* failed checksum */
307                         continue;
308                 }
309
310                 gdbstub_proto("### GDB Rx '$%s#%02x' ###\n", buffer, checksum);
311                 gdbstub_io("### GDB Tx ACK\n");
312                 gdbstub_io_tx_char('+'); /* successful transfer */
313
314                 /*
315                  * if a sequence char is present,
316                  * reply the sequence ID
317                  */
318                 if (buffer[2] == ':') {
319                         gdbstub_io_tx_char(buffer[0]);
320                         gdbstub_io_tx_char(buffer[1]);
321
322                         /*
323                          * remove sequence chars from buffer
324                          */
325                         count = 0;
326                         while (buffer[count])
327                                 count++;
328                         for (i = 3; i <= count; i++)
329                                 buffer[i - 3] = buffer[i];
330                 }
331
332                 break;
333         }
334 }
335
336 /*
337  * send the packet in buffer.
338  * - return 0 if successfully ACK'd
339  * - return 1 if abandoned due to new incoming packet
340  */
341 static int putpacket(char *buffer)
342 {
343         unsigned char checksum;
344         unsigned char ch;
345         int count;
346
347         /*
348          * $<packet info>#<checksum>.
349          */
350         gdbstub_proto("### GDB Tx $'%s'#?? ###\n", buffer);
351
352         do {
353                 gdbstub_io_tx_char('$');
354                 checksum = 0;
355                 count = 0;
356
357                 while ((ch = buffer[count]) != 0) {
358                         gdbstub_io_tx_char(ch);
359                         checksum += ch;
360                         count += 1;
361                 }
362
363                 gdbstub_io_tx_char('#');
364                 gdbstub_io_tx_char(hex_asc_hi(checksum));
365                 gdbstub_io_tx_char(hex_asc_lo(checksum));
366
367         } while (gdbstub_io_rx_char(&ch, 0),
368                  ch == '-' && (gdbstub_io("### GDB Rx NAK\n"), 0),
369                  ch != '-' && ch != '+' &&
370                  (gdbstub_io("### GDB Rx ??? %02x\n", ch), 0),
371                  ch != '+' && ch != '$');
372
373         if (ch == '+') {
374                 gdbstub_io("### GDB Rx ACK\n");
375                 return 0;
376         }
377
378         gdbstub_io("### GDB Tx Abandoned\n");
379         gdbstub_rx_unget = ch;
380         return 1;
381 }
382
383 /*
384  * While we find nice hex chars, build an int.
385  * Return number of chars processed.
386  */
387 static int hexToInt(char **ptr, int *intValue)
388 {
389         int numChars = 0;
390         int hexValue;
391
392         *intValue = 0;
393
394         while (**ptr) {
395                 hexValue = hex(**ptr);
396                 if (hexValue < 0)
397                         break;
398
399                 *intValue = (*intValue << 4) | hexValue;
400                 numChars++;
401
402                 (*ptr)++;
403         }
404
405         return (numChars);
406 }
407
408 /*
409  * We single-step by setting breakpoints. When an exception
410  * is handled, we need to restore the instructions hoisted
411  * when the breakpoints were set.
412  *
413  * This is where we save the original instructions.
414  */
415 static struct gdb_bp_save {
416         u8      *addr;
417         u8      opcode[2];
418 } step_bp[2];
419
420 static const unsigned char gdbstub_insn_sizes[256] =
421 {
422         /* 1  2  3  4  5  6  7  8  9  a  b  c  d  e  f */
423         1, 3, 3, 3, 1, 3, 3, 3, 1, 3, 3, 3, 1, 3, 3, 3, /* 0 */
424         1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 1 */
425         2, 2, 2, 2, 3, 3, 3, 3, 2, 2, 2, 2, 3, 3, 3, 3, /* 2 */
426         3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 1, 1, 1, 1, /* 3 */
427         1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 2, 2, /* 4 */
428         1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, /* 5 */
429         1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 6 */
430         1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 7 */
431         2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, /* 8 */
432         2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, /* 9 */
433         2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, /* a */
434         2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, /* b */
435         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 2, 2, /* c */
436         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* d */
437         1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* e */
438         0, 2, 2, 2, 2, 2, 2, 4, 0, 3, 0, 4, 0, 6, 7, 1  /* f */
439 };
440
441 static int __gdbstub_mark_bp(u8 *addr, int ix)
442 {
443         /* vmalloc area */
444         if (((u8 *) VMALLOC_START <= addr) && (addr < (u8 *) VMALLOC_END))
445                 goto okay;
446         /* SRAM, SDRAM */
447         if (((u8 *) 0x80000000UL <= addr) && (addr < (u8 *) 0xa0000000UL))
448                 goto okay;
449         return 0;
450
451 okay:
452         if (gdbstub_read_byte(addr + 0, &step_bp[ix].opcode[0]) < 0 ||
453             gdbstub_read_byte(addr + 1, &step_bp[ix].opcode[1]) < 0)
454                 return 0;
455
456         step_bp[ix].addr = addr;
457         return 1;
458 }
459
460 static inline void __gdbstub_restore_bp(void)
461 {
462 #ifdef GDBSTUB_USE_F7F7_AS_BREAKPOINT
463         if (step_bp[0].addr) {
464                 gdbstub_write_byte(step_bp[0].opcode[0], step_bp[0].addr + 0);
465                 gdbstub_write_byte(step_bp[0].opcode[1], step_bp[0].addr + 1);
466         }
467         if (step_bp[1].addr) {
468                 gdbstub_write_byte(step_bp[1].opcode[0], step_bp[1].addr + 0);
469                 gdbstub_write_byte(step_bp[1].opcode[1], step_bp[1].addr + 1);
470         }
471 #else
472         if (step_bp[0].addr)
473                 gdbstub_write_byte(step_bp[0].opcode[0], step_bp[0].addr + 0);
474         if (step_bp[1].addr)
475                 gdbstub_write_byte(step_bp[1].opcode[0], step_bp[1].addr + 0);
476 #endif
477
478         gdbstub_flush_caches = 1;
479
480         step_bp[0].addr         = NULL;
481         step_bp[0].opcode[0]    = 0;
482         step_bp[0].opcode[1]    = 0;
483         step_bp[1].addr         = NULL;
484         step_bp[1].opcode[0]    = 0;
485         step_bp[1].opcode[1]    = 0;
486 }
487
488 /*
489  * emulate single stepping by means of breakpoint instructions
490  */
491 static int gdbstub_single_step(struct pt_regs *regs)
492 {
493         unsigned size;
494         uint32_t x;
495         uint8_t cur, *pc, *sp;
496
497         step_bp[0].addr         = NULL;
498         step_bp[0].opcode[0]    = 0;
499         step_bp[0].opcode[1]    = 0;
500         step_bp[1].addr         = NULL;
501         step_bp[1].opcode[0]    = 0;
502         step_bp[1].opcode[1]    = 0;
503         x = 0;
504
505         pc = (u8 *) regs->pc;
506         sp = (u8 *) (regs + 1);
507         if (gdbstub_read_byte(pc, &cur) < 0)
508                 return -EFAULT;
509
510         gdbstub_bkpt("Single Step from %p { %02x }\n", pc, cur);
511
512         gdbstub_flush_caches = 1;
513
514         size = gdbstub_insn_sizes[cur];
515         if (size > 0) {
516                 if (!__gdbstub_mark_bp(pc + size, 0))
517                         goto fault;
518         } else {
519                 switch (cur) {
520                         /* Bxx (d8,PC) */
521                 case 0xc0 ... 0xca:
522                         if (gdbstub_read_byte(pc + 1, (u8 *) &x) < 0)
523                                 goto fault;
524                         if (!__gdbstub_mark_bp(pc + 2, 0))
525                                 goto fault;
526                         if ((x < 0 || x > 2) &&
527                             !__gdbstub_mark_bp(pc + (s8) x, 1))
528                                 goto fault;
529                         break;
530
531                         /* LXX (d8,PC) */
532                 case 0xd0 ... 0xda:
533                         if (!__gdbstub_mark_bp(pc + 1, 0))
534                                 goto fault;
535                         if (regs->pc != regs->lar &&
536                             !__gdbstub_mark_bp((u8 *) regs->lar, 1))
537                                 goto fault;
538                         break;
539
540                         /* SETLB - loads the next for bytes into the LIR
541                          * register */
542                 case 0xdb:
543                         if (!__gdbstub_mark_bp(pc + 1, 0))
544                                 goto fault;
545                         break;
546
547                         /* JMP (d16,PC) or CALL (d16,PC) */
548                 case 0xcc:
549                 case 0xcd:
550                         if (gdbstub_read_byte(pc + 1, ((u8 *) &x) + 0) < 0 ||
551                             gdbstub_read_byte(pc + 2, ((u8 *) &x) + 1) < 0)
552                                 goto fault;
553                         if (!__gdbstub_mark_bp(pc + (s16) x, 0))
554                                 goto fault;
555                         break;
556
557                         /* JMP (d32,PC) or CALL (d32,PC) */
558                 case 0xdc:
559                 case 0xdd:
560                         if (gdbstub_read_byte(pc + 1, ((u8 *) &x) + 0) < 0 ||
561                             gdbstub_read_byte(pc + 2, ((u8 *) &x) + 1) < 0 ||
562                             gdbstub_read_byte(pc + 3, ((u8 *) &x) + 2) < 0 ||
563                             gdbstub_read_byte(pc + 4, ((u8 *) &x) + 3) < 0)
564                                 goto fault;
565                         if (!__gdbstub_mark_bp(pc + (s32) x, 0))
566                                 goto fault;
567                         break;
568
569                         /* RETF */
570                 case 0xde:
571                         if (!__gdbstub_mark_bp((u8 *) regs->mdr, 0))
572                                 goto fault;
573                         break;
574
575                         /* RET */
576                 case 0xdf:
577                         if (gdbstub_read_byte(pc + 2, (u8 *) &x) < 0)
578                                 goto fault;
579                         sp += (s8)x;
580                         if (gdbstub_read_byte(sp + 0, ((u8 *) &x) + 0) < 0 ||
581                             gdbstub_read_byte(sp + 1, ((u8 *) &x) + 1) < 0 ||
582                             gdbstub_read_byte(sp + 2, ((u8 *) &x) + 2) < 0 ||
583                             gdbstub_read_byte(sp + 3, ((u8 *) &x) + 3) < 0)
584                                 goto fault;
585                         if (!__gdbstub_mark_bp((u8 *) x, 0))
586                                 goto fault;
587                         break;
588
589                 case 0xf0:
590                         if (gdbstub_read_byte(pc + 1, &cur) < 0)
591                                 goto fault;
592
593                         if (cur >= 0xf0 && cur <= 0xf7) {
594                                 /* JMP (An) / CALLS (An) */
595                                 switch (cur & 3) {
596                                 case 0: x = regs->a0; break;
597                                 case 1: x = regs->a1; break;
598                                 case 2: x = regs->a2; break;
599                                 case 3: x = regs->a3; break;
600                                 }
601                                 if (!__gdbstub_mark_bp((u8 *) x, 0))
602                                         goto fault;
603                         } else if (cur == 0xfc) {
604                                 /* RETS */
605                                 if (gdbstub_read_byte(
606                                             sp + 0, ((u8 *) &x) + 0) < 0 ||
607                                     gdbstub_read_byte(
608                                             sp + 1, ((u8 *) &x) + 1) < 0 ||
609                                     gdbstub_read_byte(
610                                             sp + 2, ((u8 *) &x) + 2) < 0 ||
611                                     gdbstub_read_byte(
612                                             sp + 3, ((u8 *) &x) + 3) < 0)
613                                         goto fault;
614                                 if (!__gdbstub_mark_bp((u8 *) x, 0))
615                                         goto fault;
616                         } else if (cur == 0xfd) {
617                                 /* RTI */
618                                 if (gdbstub_read_byte(
619                                             sp + 4, ((u8 *) &x) + 0) < 0 ||
620                                     gdbstub_read_byte(
621                                             sp + 5, ((u8 *) &x) + 1) < 0 ||
622                                     gdbstub_read_byte(
623                                             sp + 6, ((u8 *) &x) + 2) < 0 ||
624                                     gdbstub_read_byte(
625                                             sp + 7, ((u8 *) &x) + 3) < 0)
626                                         goto fault;
627                                 if (!__gdbstub_mark_bp((u8 *) x, 0))
628                                         goto fault;
629                         } else {
630                                 if (!__gdbstub_mark_bp(pc + 2, 0))
631                                         goto fault;
632                         }
633
634                         break;
635
636                         /* potential 3-byte conditional branches */
637                 case 0xf8:
638                         if (gdbstub_read_byte(pc + 1, &cur) < 0)
639                                 goto fault;
640                         if (!__gdbstub_mark_bp(pc + 3, 0))
641                                 goto fault;
642
643                         if (cur >= 0xe8 && cur <= 0xeb) {
644                                 if (gdbstub_read_byte(
645                                             pc + 2, ((u8 *) &x) + 0) < 0)
646                                         goto fault;
647                                 if ((x < 0 || x > 3) &&
648                                     !__gdbstub_mark_bp(pc + (s8) x, 1))
649                                         goto fault;
650                         }
651                         break;
652
653                 case 0xfa:
654                         if (gdbstub_read_byte(pc + 1, &cur) < 0)
655                                 goto fault;
656
657                         if (cur == 0xff) {
658                                 /* CALLS (d16,PC) */
659                                 if (gdbstub_read_byte(
660                                             pc + 2, ((u8 *) &x) + 0) < 0 ||
661                                     gdbstub_read_byte(
662                                             pc + 3, ((u8 *) &x) + 1) < 0)
663                                         goto fault;
664                                 if (!__gdbstub_mark_bp(pc + (s16) x, 0))
665                                         goto fault;
666                         } else {
667                                 if (!__gdbstub_mark_bp(pc + 4, 0))
668                                         goto fault;
669                         }
670                         break;
671
672                 case 0xfc:
673                         if (gdbstub_read_byte(pc + 1, &cur) < 0)
674                                 goto fault;
675                         if (cur == 0xff) {
676                                 /* CALLS (d32,PC) */
677                                 if (gdbstub_read_byte(
678                                             pc + 2, ((u8 *) &x) + 0) < 0 ||
679                                     gdbstub_read_byte(
680                                             pc + 3, ((u8 *) &x) + 1) < 0 ||
681                                     gdbstub_read_byte(
682                                             pc + 4, ((u8 *) &x) + 2) < 0 ||
683                                     gdbstub_read_byte(
684                                             pc + 5, ((u8 *) &x) + 3) < 0)
685                                         goto fault;
686                                 if (!__gdbstub_mark_bp(
687                                             pc + (s32) x, 0))
688                                         goto fault;
689                         } else {
690                                 if (!__gdbstub_mark_bp(
691                                             pc + 6, 0))
692                                         goto fault;
693                         }
694                         break;
695
696                 }
697         }
698
699         gdbstub_bkpt("Step: %02x at %p; %02x at %p\n",
700                      step_bp[0].opcode[0], step_bp[0].addr,
701                      step_bp[1].opcode[0], step_bp[1].addr);
702
703         if (step_bp[0].addr) {
704 #ifdef GDBSTUB_USE_F7F7_AS_BREAKPOINT
705                 if (gdbstub_write_byte(0xF7, step_bp[0].addr + 0) < 0 ||
706                     gdbstub_write_byte(0xF7, step_bp[0].addr + 1) < 0)
707                         goto fault;
708 #else
709                 if (gdbstub_write_byte(0xFF, step_bp[0].addr + 0) < 0)
710                         goto fault;
711 #endif
712         }
713
714         if (step_bp[1].addr) {
715 #ifdef GDBSTUB_USE_F7F7_AS_BREAKPOINT
716                 if (gdbstub_write_byte(0xF7, step_bp[1].addr + 0) < 0 ||
717                     gdbstub_write_byte(0xF7, step_bp[1].addr + 1) < 0)
718                         goto fault;
719 #else
720                 if (gdbstub_write_byte(0xFF, step_bp[1].addr + 0) < 0)
721                         goto fault;
722 #endif
723         }
724
725         return 0;
726
727  fault:
728         /* uh-oh - silly address alert, try and restore things */
729         __gdbstub_restore_bp();
730         return -EFAULT;
731 }
732
733 #ifdef CONFIG_GDBSTUB_CONSOLE
734
735 void gdbstub_console_write(struct console *con, const char *p, unsigned n)
736 {
737         static const char gdbstub_cr[] = { 0x0d };
738         char outbuf[26];
739         int qty;
740         u8 busy;
741
742         busy = gdbstub_busy;
743         gdbstub_busy = 1;
744
745         outbuf[0] = 'O';
746
747         while (n > 0) {
748                 qty = 1;
749
750                 while (n > 0 && qty < 20) {
751                         mem2hex(p, outbuf + qty, 2, 0);
752                         qty += 2;
753                         if (*p == 0x0a) {
754                                 mem2hex(gdbstub_cr, outbuf + qty, 2, 0);
755                                 qty += 2;
756                         }
757                         p++;
758                         n--;
759                 }
760
761                 outbuf[qty] = 0;
762                 putpacket(outbuf);
763         }
764
765         gdbstub_busy = busy;
766 }
767
768 static kdev_t gdbstub_console_dev(struct console *con)
769 {
770         return MKDEV(1, 3); /* /dev/null */
771 }
772
773 static struct console gdbstub_console = {
774         .name   = "gdb",
775         .write  = gdbstub_console_write,
776         .device = gdbstub_console_dev,
777         .flags  = CON_PRINTBUFFER,
778         .index  = -1,
779 };
780
781 #endif
782
783 /*
784  * Convert the memory pointed to by mem into hex, placing result in buf.
785  * - if successful, return a pointer to the last char put in buf (NUL)
786  * - in case of mem fault, return NULL
787  * may_fault is non-zero if we are reading from arbitrary memory, but is
788  * currently not used.
789  */
790 static
791 unsigned char *mem2hex(const void *_mem, char *buf, int count, int may_fault)
792 {
793         const u8 *mem = _mem;
794         u8 ch[4];
795
796         if ((u32) mem & 1 && count >= 1) {
797                 if (gdbstub_read_byte(mem, ch) != 0)
798                         return 0;
799                 buf = pack_hex_byte(buf, ch[0]);
800                 mem++;
801                 count--;
802         }
803
804         if ((u32) mem & 3 && count >= 2) {
805                 if (gdbstub_read_word(mem, ch) != 0)
806                         return 0;
807                 buf = pack_hex_byte(buf, ch[0]);
808                 buf = pack_hex_byte(buf, ch[1]);
809                 mem += 2;
810                 count -= 2;
811         }
812
813         while (count >= 4) {
814                 if (gdbstub_read_dword(mem, ch) != 0)
815                         return 0;
816                 buf = pack_hex_byte(buf, ch[0]);
817                 buf = pack_hex_byte(buf, ch[1]);
818                 buf = pack_hex_byte(buf, ch[2]);
819                 buf = pack_hex_byte(buf, ch[3]);
820                 mem += 4;
821                 count -= 4;
822         }
823
824         if (count >= 2) {
825                 if (gdbstub_read_word(mem, ch) != 0)
826                         return 0;
827                 buf = pack_hex_byte(buf, ch[0]);
828                 buf = pack_hex_byte(buf, ch[1]);
829                 mem += 2;
830                 count -= 2;
831         }
832
833         if (count >= 1) {
834                 if (gdbstub_read_byte(mem, ch) != 0)
835                         return 0;
836                 buf = pack_hex_byte(buf, ch[0]);
837         }
838
839         *buf = 0;
840         return buf;
841 }
842
843 /*
844  * convert the hex array pointed to by buf into binary to be placed in mem
845  * return a pointer to the character AFTER the last byte written
846  * may_fault is non-zero if we are reading from arbitrary memory, but is
847  * currently not used.
848  */
849 static
850 const char *hex2mem(const char *buf, void *_mem, int count, int may_fault)
851 {
852         u8 *mem = _mem;
853         union {
854                 u32 val;
855                 u8 b[4];
856         } ch;
857
858         if ((u32) mem & 1 && count >= 1) {
859                 ch.b[0]  = hex(*buf++) << 4;
860                 ch.b[0] |= hex(*buf++);
861                 if (gdbstub_write_byte(ch.val, mem) != 0)
862                         return 0;
863                 mem++;
864                 count--;
865         }
866
867         if ((u32) mem & 3 && count >= 2) {
868                 ch.b[0]  = hex(*buf++) << 4;
869                 ch.b[0] |= hex(*buf++);
870                 ch.b[1]  = hex(*buf++) << 4;
871                 ch.b[1] |= hex(*buf++);
872                 if (gdbstub_write_word(ch.val, mem) != 0)
873                         return 0;
874                 mem += 2;
875                 count -= 2;
876         }
877
878         while (count >= 4) {
879                 ch.b[0]  = hex(*buf++) << 4;
880                 ch.b[0] |= hex(*buf++);
881                 ch.b[1]  = hex(*buf++) << 4;
882                 ch.b[1] |= hex(*buf++);
883                 ch.b[2]  = hex(*buf++) << 4;
884                 ch.b[2] |= hex(*buf++);
885                 ch.b[3]  = hex(*buf++) << 4;
886                 ch.b[3] |= hex(*buf++);
887                 if (gdbstub_write_dword(ch.val, mem) != 0)
888                         return 0;
889                 mem += 4;
890                 count -= 4;
891         }
892
893         if (count >= 2) {
894                 ch.b[0]  = hex(*buf++) << 4;
895                 ch.b[0] |= hex(*buf++);
896                 ch.b[1]  = hex(*buf++) << 4;
897                 ch.b[1] |= hex(*buf++);
898                 if (gdbstub_write_word(ch.val, mem) != 0)
899                         return 0;
900                 mem += 2;
901                 count -= 2;
902         }
903
904         if (count >= 1) {
905                 ch.b[0]  = hex(*buf++) << 4;
906                 ch.b[0] |= hex(*buf++);
907                 if (gdbstub_write_byte(ch.val, mem) != 0)
908                         return 0;
909         }
910
911         return buf;
912 }
913
914 /*
915  * This table contains the mapping between MN10300 exception codes, and
916  * signals, which are primarily what GDB understands.  It also indicates
917  * which hardware traps we need to commandeer when initializing the stub.
918  */
919 static const struct excep_to_sig_map {
920         enum exception_code     excep;  /* MN10300 exception code */
921         unsigned char           signo;  /* Signal that we map this into */
922 } excep_to_sig_map[] = {
923         { EXCEP_ITLBMISS,       SIGSEGV         },
924         { EXCEP_DTLBMISS,       SIGSEGV         },
925         { EXCEP_TRAP,           SIGTRAP         },
926         { EXCEP_ISTEP,          SIGTRAP         },
927         { EXCEP_IBREAK,         SIGTRAP         },
928         { EXCEP_OBREAK,         SIGTRAP         },
929         { EXCEP_UNIMPINS,       SIGILL          },
930         { EXCEP_UNIMPEXINS,     SIGILL          },
931         { EXCEP_MEMERR,         SIGSEGV         },
932         { EXCEP_MISALIGN,       SIGSEGV         },
933         { EXCEP_BUSERROR,       SIGBUS          },
934         { EXCEP_ILLINSACC,      SIGSEGV         },
935         { EXCEP_ILLDATACC,      SIGSEGV         },
936         { EXCEP_IOINSACC,       SIGSEGV         },
937         { EXCEP_PRIVINSACC,     SIGSEGV         },
938         { EXCEP_PRIVDATACC,     SIGSEGV         },
939         { EXCEP_FPU_DISABLED,   SIGFPE          },
940         { EXCEP_FPU_UNIMPINS,   SIGFPE          },
941         { EXCEP_FPU_OPERATION,  SIGFPE          },
942         { EXCEP_WDT,            SIGALRM         },
943         { EXCEP_NMI,            SIGQUIT         },
944         { EXCEP_IRQ_LEVEL0,     SIGINT          },
945         { EXCEP_IRQ_LEVEL1,     SIGINT          },
946         { EXCEP_IRQ_LEVEL2,     SIGINT          },
947         { EXCEP_IRQ_LEVEL3,     SIGINT          },
948         { EXCEP_IRQ_LEVEL4,     SIGINT          },
949         { EXCEP_IRQ_LEVEL5,     SIGINT          },
950         { EXCEP_IRQ_LEVEL6,     SIGINT          },
951         { 0, 0}
952 };
953
954 /*
955  * convert the MN10300 exception code into a UNIX signal number
956  */
957 static int computeSignal(enum exception_code excep)
958 {
959         const struct excep_to_sig_map *map;
960
961         for (map = excep_to_sig_map; map->signo; map++)
962                 if (map->excep == excep)
963                         return map->signo;
964
965         return SIGHUP; /* default for things we don't know about */
966 }
967
968 static u32 gdbstub_fpcr, gdbstub_fpufs_array[32];
969
970 /*
971  *
972  */
973 static void gdbstub_store_fpu(void)
974 {
975 #ifdef CONFIG_FPU
976
977         asm volatile(
978                 "or %2,epsw\n"
979 #ifdef CONFIG_MN10300_PROC_MN103E010
980                 "nop\n"
981                 "nop\n"
982 #endif
983                 "mov %1, a1\n"
984                 "fmov fs0,  (a1+)\n"
985                 "fmov fs1,  (a1+)\n"
986                 "fmov fs2,  (a1+)\n"
987                 "fmov fs3,  (a1+)\n"
988                 "fmov fs4,  (a1+)\n"
989                 "fmov fs5,  (a1+)\n"
990                 "fmov fs6,  (a1+)\n"
991                 "fmov fs7,  (a1+)\n"
992                 "fmov fs8,  (a1+)\n"
993                 "fmov fs9,  (a1+)\n"
994                 "fmov fs10, (a1+)\n"
995                 "fmov fs11, (a1+)\n"
996                 "fmov fs12, (a1+)\n"
997                 "fmov fs13, (a1+)\n"
998                 "fmov fs14, (a1+)\n"
999                 "fmov fs15, (a1+)\n"
1000                 "fmov fs16, (a1+)\n"
1001                 "fmov fs17, (a1+)\n"
1002                 "fmov fs18, (a1+)\n"
1003                 "fmov fs19, (a1+)\n"
1004                 "fmov fs20, (a1+)\n"
1005                 "fmov fs21, (a1+)\n"
1006                 "fmov fs22, (a1+)\n"
1007                 "fmov fs23, (a1+)\n"
1008                 "fmov fs24, (a1+)\n"
1009                 "fmov fs25, (a1+)\n"
1010                 "fmov fs26, (a1+)\n"
1011                 "fmov fs27, (a1+)\n"
1012                 "fmov fs28, (a1+)\n"
1013                 "fmov fs29, (a1+)\n"
1014                 "fmov fs30, (a1+)\n"
1015                 "fmov fs31, (a1+)\n"
1016                 "fmov fpcr, %0\n"
1017                 : "=d"(gdbstub_fpcr)
1018                 : "g" (&gdbstub_fpufs_array), "i"(EPSW_FE)
1019                 : "a1"
1020                 );
1021 #endif
1022 }
1023
1024 /*
1025  *
1026  */
1027 static void gdbstub_load_fpu(void)
1028 {
1029 #ifdef CONFIG_FPU
1030
1031         asm volatile(
1032                 "or %1,epsw\n"
1033 #ifdef CONFIG_MN10300_PROC_MN103E010
1034                 "nop\n"
1035                 "nop\n"
1036 #endif
1037                 "mov %0, a1\n"
1038                 "fmov (a1+), fs0\n"
1039                 "fmov (a1+), fs1\n"
1040                 "fmov (a1+), fs2\n"
1041                 "fmov (a1+), fs3\n"
1042                 "fmov (a1+), fs4\n"
1043                 "fmov (a1+), fs5\n"
1044                 "fmov (a1+), fs6\n"
1045                 "fmov (a1+), fs7\n"
1046                 "fmov (a1+), fs8\n"
1047                 "fmov (a1+), fs9\n"
1048                 "fmov (a1+), fs10\n"
1049                 "fmov (a1+), fs11\n"
1050                 "fmov (a1+), fs12\n"
1051                 "fmov (a1+), fs13\n"
1052                 "fmov (a1+), fs14\n"
1053                 "fmov (a1+), fs15\n"
1054                 "fmov (a1+), fs16\n"
1055                 "fmov (a1+), fs17\n"
1056                 "fmov (a1+), fs18\n"
1057                 "fmov (a1+), fs19\n"
1058                 "fmov (a1+), fs20\n"
1059                 "fmov (a1+), fs21\n"
1060                 "fmov (a1+), fs22\n"
1061                 "fmov (a1+), fs23\n"
1062                 "fmov (a1+), fs24\n"
1063                 "fmov (a1+), fs25\n"
1064                 "fmov (a1+), fs26\n"
1065                 "fmov (a1+), fs27\n"
1066                 "fmov (a1+), fs28\n"
1067                 "fmov (a1+), fs29\n"
1068                 "fmov (a1+), fs30\n"
1069                 "fmov (a1+), fs31\n"
1070                 "fmov %2, fpcr\n"
1071                 :
1072                 : "g" (&gdbstub_fpufs_array), "i"(EPSW_FE), "d"(gdbstub_fpcr)
1073                 : "a1"
1074         );
1075 #endif
1076 }
1077
1078 /*
1079  * set a software breakpoint
1080  */
1081 int gdbstub_set_breakpoint(u8 *addr, int len)
1082 {
1083         int bkpt, loop, xloop;
1084
1085 #ifdef GDBSTUB_USE_F7F7_AS_BREAKPOINT
1086         len = (len + 1) & ~1;
1087 #endif
1088
1089         gdbstub_bkpt("setbkpt(%p,%d)\n", addr, len);
1090
1091         for (bkpt = 255; bkpt >= 0; bkpt--)
1092                 if (!gdbstub_bkpts[bkpt].addr)
1093                         break;
1094         if (bkpt < 0)
1095                 return -ENOSPC;
1096
1097         for (loop = 0; loop < len; loop++)
1098                 if (gdbstub_read_byte(&addr[loop],
1099                                       &gdbstub_bkpts[bkpt].origbytes[loop]
1100                                       ) < 0)
1101                         return -EFAULT;
1102
1103         gdbstub_flush_caches = 1;
1104
1105 #ifdef GDBSTUB_USE_F7F7_AS_BREAKPOINT
1106         for (loop = 0; loop < len; loop++)
1107                 if (gdbstub_write_byte(0xF7, &addr[loop]) < 0)
1108                         goto restore;
1109 #else
1110         for (loop = 0; loop < len; loop++)
1111                 if (gdbstub_write_byte(0xFF, &addr[loop]) < 0)
1112                         goto restore;
1113 #endif
1114
1115         gdbstub_bkpts[bkpt].addr = addr;
1116         gdbstub_bkpts[bkpt].len = len;
1117
1118         gdbstub_bkpt("Set BKPT[%02x]: %p-%p {%02x%02x%02x%02x%02x%02x%02x}\n",
1119                      bkpt,
1120                      gdbstub_bkpts[bkpt].addr,
1121                      gdbstub_bkpts[bkpt].addr + gdbstub_bkpts[bkpt].len - 1,
1122                      gdbstub_bkpts[bkpt].origbytes[0],
1123                      gdbstub_bkpts[bkpt].origbytes[1],
1124                      gdbstub_bkpts[bkpt].origbytes[2],
1125                      gdbstub_bkpts[bkpt].origbytes[3],
1126                      gdbstub_bkpts[bkpt].origbytes[4],
1127                      gdbstub_bkpts[bkpt].origbytes[5],
1128                      gdbstub_bkpts[bkpt].origbytes[6]
1129                      );
1130
1131         return 0;
1132
1133 restore:
1134         for (xloop = 0; xloop < loop; xloop++)
1135                 gdbstub_write_byte(gdbstub_bkpts[bkpt].origbytes[xloop],
1136                                    addr + xloop);
1137         return -EFAULT;
1138 }
1139
1140 /*
1141  * clear a software breakpoint
1142  */
1143 int gdbstub_clear_breakpoint(u8 *addr, int len)
1144 {
1145         int bkpt, loop;
1146
1147 #ifdef GDBSTUB_USE_F7F7_AS_BREAKPOINT
1148         len = (len + 1) & ~1;
1149 #endif
1150
1151         gdbstub_bkpt("clearbkpt(%p,%d)\n", addr, len);
1152
1153         for (bkpt = 255; bkpt >= 0; bkpt--)
1154                 if (gdbstub_bkpts[bkpt].addr == addr &&
1155                     gdbstub_bkpts[bkpt].len == len)
1156                         break;
1157         if (bkpt < 0)
1158                 return -ENOENT;
1159
1160         gdbstub_bkpts[bkpt].addr = NULL;
1161
1162         gdbstub_flush_caches = 1;
1163
1164         for (loop = 0; loop < len; loop++)
1165                 if (gdbstub_write_byte(gdbstub_bkpts[bkpt].origbytes[loop],
1166                                        addr + loop) < 0)
1167                         return -EFAULT;
1168
1169         return 0;
1170 }
1171
1172 /*
1173  * This function does all command processing for interfacing to gdb
1174  * - returns 1 if the exception should be skipped, 0 otherwise.
1175  */
1176 static int gdbstub(struct pt_regs *regs, enum exception_code excep)
1177 {
1178         unsigned long *stack;
1179         unsigned long epsw, mdr;
1180         uint32_t zero, ssp;
1181         uint8_t broke;
1182         char *ptr;
1183         int sigval;
1184         int addr;
1185         int length;
1186         int loop;
1187
1188         if (excep == EXCEP_FPU_DISABLED)
1189                 return 0;
1190
1191         gdbstub_flush_caches = 0;
1192
1193         mn10300_set_gdbleds(1);
1194
1195         asm volatile("mov mdr,%0" : "=d"(mdr));
1196         local_save_flags(epsw);
1197         arch_local_change_intr_mask_level(
1198                 NUM2EPSW_IM(CONFIG_GDBSTUB_IRQ_LEVEL + 1));
1199
1200         gdbstub_store_fpu();
1201
1202 #ifdef CONFIG_GDBSTUB_IMMEDIATE
1203         /* skip the initial pause loop */
1204         if (regs->pc == (unsigned long) __gdbstub_pause)
1205                 regs->pc = (unsigned long) start_kernel;
1206 #endif
1207
1208         /* if we were single stepping, restore the opcodes hoisted for the
1209          * breakpoint[s] */
1210         broke = 0;
1211         if ((step_bp[0].addr && step_bp[0].addr == (u8 *) regs->pc) ||
1212             (step_bp[1].addr && step_bp[1].addr == (u8 *) regs->pc))
1213                 broke = 1;
1214
1215         __gdbstub_restore_bp();
1216
1217         if (gdbstub_rx_unget) {
1218                 sigval = SIGINT;
1219                 if (gdbstub_rx_unget != 3)
1220                         goto packet_waiting;
1221                 gdbstub_rx_unget = 0;
1222         }
1223
1224         stack = (unsigned long *) regs->sp;
1225         sigval = broke ? SIGTRAP : computeSignal(excep);
1226
1227         /* send information about a BUG() */
1228         if (!user_mode(regs) && excep == EXCEP_SYSCALL15) {
1229                 const struct bug_entry *bug;
1230
1231                 bug = find_bug(regs->pc);
1232                 if (bug)
1233                         goto found_bug;
1234                 length = snprintf(trans_buffer, sizeof(trans_buffer),
1235                                   "BUG() at address %lx\n", regs->pc);
1236                 goto send_bug_pkt;
1237
1238         found_bug:
1239                 length = snprintf(trans_buffer, sizeof(trans_buffer),
1240                                   "BUG() at address %lx (%s:%d)\n",
1241                                   regs->pc, bug->file, bug->line);
1242
1243         send_bug_pkt:
1244                 ptr = output_buffer;
1245                 *ptr++ = 'O';
1246                 ptr = mem2hex(trans_buffer, ptr, length, 0);
1247                 *ptr = 0;
1248                 putpacket(output_buffer);
1249
1250                 regs->pc -= 2;
1251                 sigval = SIGABRT;
1252         } else if (regs->pc == (unsigned long) __gdbstub_bug_trap) {
1253                 regs->pc = regs->mdr;
1254                 sigval = SIGABRT;
1255         }
1256
1257         /*
1258          * send a message to the debugger's user saying what happened if it may
1259          * not be clear cut (we can't map exceptions onto signals properly)
1260          */
1261         if (sigval != SIGINT && sigval != SIGTRAP && sigval != SIGILL) {
1262                 static const char title[] = "Excep ", tbcberr[] = "BCBERR ";
1263                 static const char crlf[] = "\r\n";
1264                 char hx;
1265                 u32 bcberr = BCBERR;
1266
1267                 ptr = output_buffer;
1268                 *ptr++ = 'O';
1269                 ptr = mem2hex(title, ptr, sizeof(title) - 1, 0);
1270
1271                 hx = hex_asc_hi(excep >> 8);
1272                 ptr = pack_hex_byte(ptr, hx);
1273                 hx = hex_asc_lo(excep >> 8);
1274                 ptr = pack_hex_byte(ptr, hx);
1275                 hx = hex_asc_hi(excep);
1276                 ptr = pack_hex_byte(ptr, hx);
1277                 hx = hex_asc_lo(excep);
1278                 ptr = pack_hex_byte(ptr, hx);
1279
1280                 ptr = mem2hex(crlf, ptr, sizeof(crlf) - 1, 0);
1281                 *ptr = 0;
1282                 putpacket(output_buffer);       /* send it off... */
1283
1284                 /* BCBERR */
1285                 ptr = output_buffer;
1286                 *ptr++ = 'O';
1287                 ptr = mem2hex(tbcberr, ptr, sizeof(tbcberr) - 1, 0);
1288
1289                 hx = hex_asc_hi(bcberr >> 24);
1290                 ptr = pack_hex_byte(ptr, hx);
1291                 hx = hex_asc_lo(bcberr >> 24);
1292                 ptr = pack_hex_byte(ptr, hx);
1293                 hx = hex_asc_hi(bcberr >> 16);
1294                 ptr = pack_hex_byte(ptr, hx);
1295                 hx = hex_asc_lo(bcberr >> 16);
1296                 ptr = pack_hex_byte(ptr, hx);
1297                 hx = hex_asc_hi(bcberr >> 8);
1298                 ptr = pack_hex_byte(ptr, hx);
1299                 hx = hex_asc_lo(bcberr >> 8);
1300                 ptr = pack_hex_byte(ptr, hx);
1301                 hx = hex_asc_hi(bcberr);
1302                 ptr = pack_hex_byte(ptr, hx);
1303                 hx = hex_asc_lo(bcberr);
1304                 ptr = pack_hex_byte(ptr, hx);
1305
1306                 ptr = mem2hex(crlf, ptr, sizeof(crlf) - 1, 0);
1307                 *ptr = 0;
1308                 putpacket(output_buffer);       /* send it off... */
1309         }
1310
1311         /*
1312          * tell the debugger that an exception has occurred
1313          */
1314         ptr = output_buffer;
1315
1316         /*
1317          * Send trap type (converted to signal)
1318          */
1319         *ptr++ = 'T';
1320         ptr = pack_hex_byte(ptr, sigval);
1321
1322         /*
1323          * Send Error PC
1324          */
1325         ptr = pack_hex_byte(ptr, GDB_REGID_PC);
1326         *ptr++ = ':';
1327         ptr = mem2hex(&regs->pc, ptr, 4, 0);
1328         *ptr++ = ';';
1329
1330         /*
1331          * Send frame pointer
1332          */
1333         ptr = pack_hex_byte(ptr, GDB_REGID_FP);
1334         *ptr++ = ':';
1335         ptr = mem2hex(&regs->a3, ptr, 4, 0);
1336         *ptr++ = ';';
1337
1338         /*
1339          * Send stack pointer
1340          */
1341         ssp = (unsigned long) (regs + 1);
1342         ptr = pack_hex_byte(ptr, GDB_REGID_SP);
1343         *ptr++ = ':';
1344         ptr = mem2hex(&ssp, ptr, 4, 0);
1345         *ptr++ = ';';
1346
1347         *ptr++ = 0;
1348         putpacket(output_buffer);       /* send it off... */
1349
1350 packet_waiting:
1351         /*
1352          * Wait for input from remote GDB
1353          */
1354         while (1) {
1355                 output_buffer[0] = 0;
1356                 getpacket(input_buffer);
1357
1358                 switch (input_buffer[0]) {
1359                         /* request repeat of last signal number */
1360                 case '?':
1361                         output_buffer[0] = 'S';
1362                         output_buffer[1] = hex_asc_hi(sigval);
1363                         output_buffer[2] = hex_asc_lo(sigval);
1364                         output_buffer[3] = 0;
1365                         break;
1366
1367                 case 'd':
1368                         /* toggle debug flag */
1369                         break;
1370
1371                         /*
1372                          * Return the value of the CPU registers
1373                          */
1374                 case 'g':
1375                         zero = 0;
1376                         ssp = (u32) (regs + 1);
1377                         ptr = output_buffer;
1378                         ptr = mem2hex(&regs->d0, ptr, 4, 0);
1379                         ptr = mem2hex(&regs->d1, ptr, 4, 0);
1380                         ptr = mem2hex(&regs->d2, ptr, 4, 0);
1381                         ptr = mem2hex(&regs->d3, ptr, 4, 0);
1382                         ptr = mem2hex(&regs->a0, ptr, 4, 0);
1383                         ptr = mem2hex(&regs->a1, ptr, 4, 0);
1384                         ptr = mem2hex(&regs->a2, ptr, 4, 0);
1385                         ptr = mem2hex(&regs->a3, ptr, 4, 0);
1386
1387                         ptr = mem2hex(&ssp, ptr, 4, 0);         /* 8 */
1388                         ptr = mem2hex(&regs->pc, ptr, 4, 0);
1389                         ptr = mem2hex(&regs->mdr, ptr, 4, 0);
1390                         ptr = mem2hex(&regs->epsw, ptr, 4, 0);
1391                         ptr = mem2hex(&regs->lir, ptr, 4, 0);
1392                         ptr = mem2hex(&regs->lar, ptr, 4, 0);
1393                         ptr = mem2hex(&regs->mdrq, ptr, 4, 0);
1394
1395                         ptr = mem2hex(&regs->e0, ptr, 4, 0);    /* 15 */
1396                         ptr = mem2hex(&regs->e1, ptr, 4, 0);
1397                         ptr = mem2hex(&regs->e2, ptr, 4, 0);
1398                         ptr = mem2hex(&regs->e3, ptr, 4, 0);
1399                         ptr = mem2hex(&regs->e4, ptr, 4, 0);
1400                         ptr = mem2hex(&regs->e5, ptr, 4, 0);
1401                         ptr = mem2hex(&regs->e6, ptr, 4, 0);
1402                         ptr = mem2hex(&regs->e7, ptr, 4, 0);
1403
1404                         ptr = mem2hex(&ssp, ptr, 4, 0);
1405                         ptr = mem2hex(&regs, ptr, 4, 0);
1406                         ptr = mem2hex(&regs->sp, ptr, 4, 0);
1407                         ptr = mem2hex(&regs->mcrh, ptr, 4, 0);  /* 26 */
1408                         ptr = mem2hex(&regs->mcrl, ptr, 4, 0);
1409                         ptr = mem2hex(&regs->mcvf, ptr, 4, 0);
1410
1411                         ptr = mem2hex(&gdbstub_fpcr, ptr, 4, 0); /* 29 - FPCR */
1412                         ptr = mem2hex(&zero, ptr, 4, 0);
1413                         ptr = mem2hex(&zero, ptr, 4, 0);
1414                         for (loop = 0; loop < 32; loop++)
1415                                 ptr = mem2hex(&gdbstub_fpufs_array[loop],
1416                                               ptr, 4, 0); /* 32 - FS0-31 */
1417
1418                         break;
1419
1420                         /*
1421                          * set the value of the CPU registers - return OK
1422                          */
1423                 case 'G':
1424                 {
1425                         const char *ptr;
1426
1427                         ptr = &input_buffer[1];
1428                         ptr = hex2mem(ptr, &regs->d0, 4, 0);
1429                         ptr = hex2mem(ptr, &regs->d1, 4, 0);
1430                         ptr = hex2mem(ptr, &regs->d2, 4, 0);
1431                         ptr = hex2mem(ptr, &regs->d3, 4, 0);
1432                         ptr = hex2mem(ptr, &regs->a0, 4, 0);
1433                         ptr = hex2mem(ptr, &regs->a1, 4, 0);
1434                         ptr = hex2mem(ptr, &regs->a2, 4, 0);
1435                         ptr = hex2mem(ptr, &regs->a3, 4, 0);
1436
1437                         ptr = hex2mem(ptr, &ssp, 4, 0);         /* 8 */
1438                         ptr = hex2mem(ptr, &regs->pc, 4, 0);
1439                         ptr = hex2mem(ptr, &regs->mdr, 4, 0);
1440                         ptr = hex2mem(ptr, &regs->epsw, 4, 0);
1441                         ptr = hex2mem(ptr, &regs->lir, 4, 0);
1442                         ptr = hex2mem(ptr, &regs->lar, 4, 0);
1443                         ptr = hex2mem(ptr, &regs->mdrq, 4, 0);
1444
1445                         ptr = hex2mem(ptr, &regs->e0, 4, 0);    /* 15 */
1446                         ptr = hex2mem(ptr, &regs->e1, 4, 0);
1447                         ptr = hex2mem(ptr, &regs->e2, 4, 0);
1448                         ptr = hex2mem(ptr, &regs->e3, 4, 0);
1449                         ptr = hex2mem(ptr, &regs->e4, 4, 0);
1450                         ptr = hex2mem(ptr, &regs->e5, 4, 0);
1451                         ptr = hex2mem(ptr, &regs->e6, 4, 0);
1452                         ptr = hex2mem(ptr, &regs->e7, 4, 0);
1453
1454                         ptr = hex2mem(ptr, &ssp, 4, 0);
1455                         ptr = hex2mem(ptr, &zero, 4, 0);
1456                         ptr = hex2mem(ptr, &regs->sp, 4, 0);
1457                         ptr = hex2mem(ptr, &regs->mcrh, 4, 0);  /* 26 */
1458                         ptr = hex2mem(ptr, &regs->mcrl, 4, 0);
1459                         ptr = hex2mem(ptr, &regs->mcvf, 4, 0);
1460
1461                         ptr = hex2mem(ptr, &zero, 4, 0);        /* 29 - FPCR */
1462                         ptr = hex2mem(ptr, &zero, 4, 0);
1463                         ptr = hex2mem(ptr, &zero, 4, 0);
1464                         for (loop = 0; loop < 32; loop++)     /* 32 - FS0-31 */
1465                                 ptr = hex2mem(ptr, &zero, 4, 0);
1466
1467 #if 0
1468                         /*
1469                          * See if the stack pointer has moved. If so, then copy
1470                          * the saved locals and ins to the new location.
1471                          */
1472                         unsigned long *newsp = (unsigned long *) registers[SP];
1473                         if (sp != newsp)
1474                                 sp = memcpy(newsp, sp, 16 * 4);
1475 #endif
1476
1477                         gdbstub_strcpy(output_buffer, "OK");
1478                 }
1479                 break;
1480
1481                 /*
1482                  * mAA..AA,LLLL  Read LLLL bytes at address AA..AA
1483                  */
1484                 case 'm':
1485                         ptr = &input_buffer[1];
1486
1487                         if (hexToInt(&ptr, &addr) &&
1488                             *ptr++ == ',' &&
1489                             hexToInt(&ptr, &length)
1490                             ) {
1491                                 if (mem2hex((char *) addr, output_buffer,
1492                                             length, 1))
1493                                         break;
1494                                 gdbstub_strcpy(output_buffer, "E03");
1495                         } else {
1496                                 gdbstub_strcpy(output_buffer, "E01");
1497                         }
1498                         break;
1499
1500                         /*
1501                          * MAA..AA,LLLL: Write LLLL bytes at address AA.AA
1502                          * return OK
1503                          */
1504                 case 'M':
1505                         ptr = &input_buffer[1];
1506
1507                         if (hexToInt(&ptr, &addr) &&
1508                             *ptr++ == ',' &&
1509                             hexToInt(&ptr, &length) &&
1510                             *ptr++ == ':'
1511                             ) {
1512                                 if (hex2mem(ptr, (char *) addr, length, 1))
1513                                         gdbstub_strcpy(output_buffer, "OK");
1514                                 else
1515                                         gdbstub_strcpy(output_buffer, "E03");
1516
1517                                 gdbstub_flush_caches = 1;
1518                         } else {
1519                                 gdbstub_strcpy(output_buffer, "E02");
1520                         }
1521                         break;
1522
1523                         /*
1524                          * cAA..AA    Continue at address AA..AA(optional)
1525                          */
1526                 case 'c':
1527                         /* try to read optional parameter, pc unchanged if no
1528                          * parm */
1529
1530                         ptr = &input_buffer[1];
1531                         if (hexToInt(&ptr, &addr))
1532                                 regs->pc = addr;
1533                         goto done;
1534
1535                         /*
1536                          * kill the program
1537                          */
1538                 case 'k' :
1539                         goto done;      /* just continue */
1540
1541                         /*
1542                          * Reset the whole machine (FIXME: system dependent)
1543                          */
1544                 case 'r':
1545                         break;
1546
1547                         /*
1548                          * Step to next instruction
1549                          */
1550                 case 's':
1551                         /*
1552                          * using the T flag doesn't seem to perform single
1553                          * stepping (it seems to wind up being caught by the
1554                          * JTAG unit), so we have to use breakpoints and
1555                          * continue instead.
1556                          */
1557                         if (gdbstub_single_step(regs) < 0)
1558                                 /* ignore any fault error for now */
1559                                 gdbstub_printk("unable to set single-step"
1560                                                " bp\n");
1561                         goto done;
1562
1563                         /*
1564                          * Set baud rate (bBB)
1565                          */
1566                 case 'b':
1567                         do {
1568                                 int baudrate;
1569
1570                                 ptr = &input_buffer[1];
1571                                 if (!hexToInt(&ptr, &baudrate)) {
1572                                         gdbstub_strcpy(output_buffer, "B01");
1573                                         break;
1574                                 }
1575
1576                                 if (baudrate) {
1577                                         /* ACK before changing speed */
1578                                         putpacket("OK");
1579                                         gdbstub_io_set_baud(baudrate);
1580                                 }
1581                         } while (0);
1582                         break;
1583
1584                         /*
1585                          * Set breakpoint
1586                          */
1587                 case 'Z':
1588                         ptr = &input_buffer[1];
1589
1590                         if (!hexToInt(&ptr, &loop) || *ptr++ != ',' ||
1591                             !hexToInt(&ptr, &addr) || *ptr++ != ',' ||
1592                             !hexToInt(&ptr, &length)
1593                             ) {
1594                                 gdbstub_strcpy(output_buffer, "E01");
1595                                 break;
1596                         }
1597
1598                         /* only support software breakpoints */
1599                         gdbstub_strcpy(output_buffer, "E03");
1600                         if (loop != 0 ||
1601                             length < 1 ||
1602                             length > 7 ||
1603                             (unsigned long) addr < 4096)
1604                                 break;
1605
1606                         if (gdbstub_set_breakpoint((u8 *) addr, length) < 0)
1607                                 break;
1608
1609                         gdbstub_strcpy(output_buffer, "OK");
1610                         break;
1611
1612                         /*
1613                          * Clear breakpoint
1614                          */
1615                 case 'z':
1616                         ptr = &input_buffer[1];
1617
1618                         if (!hexToInt(&ptr, &loop) || *ptr++ != ',' ||
1619                             !hexToInt(&ptr, &addr) || *ptr++ != ',' ||
1620                             !hexToInt(&ptr, &length)
1621                             ) {
1622                                 gdbstub_strcpy(output_buffer, "E01");
1623                                 break;
1624                         }
1625
1626                         /* only support software breakpoints */
1627                         gdbstub_strcpy(output_buffer, "E03");
1628                         if (loop != 0 ||
1629                             length < 1 ||
1630                             length > 7 ||
1631                             (unsigned long) addr < 4096)
1632                                 break;
1633
1634                         if (gdbstub_clear_breakpoint((u8 *) addr, length) < 0)
1635                                 break;
1636
1637                         gdbstub_strcpy(output_buffer, "OK");
1638                         break;
1639
1640                 default:
1641                         gdbstub_proto("### GDB Unsupported Cmd '%s'\n",
1642                                       input_buffer);
1643                         break;
1644                 }
1645
1646                 /* reply to the request */
1647                 putpacket(output_buffer);
1648         }
1649
1650 done:
1651         /*
1652          * Need to flush the instruction cache here, as we may
1653          * have deposited a breakpoint, and the icache probably
1654          * has no way of knowing that a data ref to some location
1655          * may have changed something that is in the instruction
1656          * cache.
1657          * NB: We flush both caches, just to be sure...
1658          */
1659         if (gdbstub_flush_caches)
1660                 gdbstub_purge_cache();
1661
1662         gdbstub_load_fpu();
1663         mn10300_set_gdbleds(0);
1664         if (excep == EXCEP_NMI)
1665                 NMICR = NMICR_NMIF;
1666
1667         touch_softlockup_watchdog();
1668
1669         local_irq_restore(epsw);
1670         return 1;
1671 }
1672
1673 /*
1674  * handle event interception
1675  */
1676 asmlinkage int gdbstub_intercept(struct pt_regs *regs,
1677                                  enum exception_code excep)
1678 {
1679         static u8 notfirst = 1;
1680         int ret;
1681
1682         if (gdbstub_busy)
1683                 gdbstub_printk("--> gdbstub reentered itself\n");
1684         gdbstub_busy = 1;
1685
1686         if (notfirst) {
1687                 unsigned long mdr;
1688                 asm("mov mdr,%0" : "=d"(mdr));
1689
1690                 gdbstub_entry(
1691                         "--> gdbstub_intercept(%p,%04x) [MDR=%lx PC=%lx]\n",
1692                         regs, excep, mdr, regs->pc);
1693
1694                 gdbstub_entry(
1695                         "PC:  %08lx EPSW:  %08lx  SSP: %08lx mode: %s\n",
1696                         regs->pc, regs->epsw, (unsigned long) &ret,
1697                         user_mode(regs) ? "User" : "Super");
1698                 gdbstub_entry(
1699                         "d0:  %08lx   d1:  %08lx   d2: %08lx   d3: %08lx\n",
1700                         regs->d0, regs->d1, regs->d2, regs->d3);
1701                 gdbstub_entry(
1702                         "a0:  %08lx   a1:  %08lx   a2: %08lx   a3: %08lx\n",
1703                         regs->a0, regs->a1, regs->a2, regs->a3);
1704                 gdbstub_entry(
1705                         "e0:  %08lx   e1:  %08lx   e2: %08lx   e3: %08lx\n",
1706                         regs->e0, regs->e1, regs->e2, regs->e3);
1707                 gdbstub_entry(
1708                         "e4:  %08lx   e5:  %08lx   e6: %08lx   e7: %08lx\n",
1709                         regs->e4, regs->e5, regs->e6, regs->e7);
1710                 gdbstub_entry(
1711                         "lar: %08lx   lir: %08lx  mdr: %08lx  usp: %08lx\n",
1712                         regs->lar, regs->lir, regs->mdr, regs->sp);
1713                 gdbstub_entry(
1714                         "cvf: %08lx   crl: %08lx  crh: %08lx  drq: %08lx\n",
1715                         regs->mcvf, regs->mcrl, regs->mcrh, regs->mdrq);
1716                 gdbstub_entry(
1717                         "threadinfo=%p task=%p)\n",
1718                         current_thread_info(), current);
1719         } else {
1720                 notfirst = 1;
1721         }
1722
1723         ret = gdbstub(regs, excep);
1724
1725         gdbstub_entry("<-- gdbstub_intercept()\n");
1726         gdbstub_busy = 0;
1727         return ret;
1728 }
1729
1730 /*
1731  * handle the GDB stub itself causing an exception
1732  */
1733 asmlinkage void gdbstub_exception(struct pt_regs *regs,
1734                                   enum exception_code excep)
1735 {
1736         unsigned long mdr;
1737
1738         asm("mov mdr,%0" : "=d"(mdr));
1739         gdbstub_entry("--> gdbstub exception({%p},%04x) [MDR=%lx]\n",
1740                       regs, excep, mdr);
1741
1742         while ((unsigned long) regs == 0xffffffff) {}
1743
1744         /* handle guarded memory accesses where we know it might fault */
1745         if (regs->pc == (unsigned) gdbstub_read_byte_guard) {
1746                 regs->pc = (unsigned) gdbstub_read_byte_cont;
1747                 goto fault;
1748         }
1749
1750         if (regs->pc == (unsigned) gdbstub_read_word_guard) {
1751                 regs->pc = (unsigned) gdbstub_read_word_cont;
1752                 goto fault;
1753         }
1754
1755         if (regs->pc == (unsigned) gdbstub_read_dword_guard) {
1756                 regs->pc = (unsigned) gdbstub_read_dword_cont;
1757                 goto fault;
1758         }
1759
1760         if (regs->pc == (unsigned) gdbstub_write_byte_guard) {
1761                 regs->pc = (unsigned) gdbstub_write_byte_cont;
1762                 goto fault;
1763         }
1764
1765         if (regs->pc == (unsigned) gdbstub_write_word_guard) {
1766                 regs->pc = (unsigned) gdbstub_write_word_cont;
1767                 goto fault;
1768         }
1769
1770         if (regs->pc == (unsigned) gdbstub_write_dword_guard) {
1771                 regs->pc = (unsigned) gdbstub_write_dword_cont;
1772                 goto fault;
1773         }
1774
1775         gdbstub_printk("\n### GDB stub caused an exception ###\n");
1776
1777         /* something went horribly wrong */
1778         console_verbose();
1779         show_registers(regs);
1780
1781         panic("GDB Stub caused an unexpected exception - can't continue\n");
1782
1783         /* we caught an attempt by the stub to access silly memory */
1784 fault:
1785         gdbstub_entry("<-- gdbstub exception() = EFAULT\n");
1786         regs->d0 = -EFAULT;
1787         return;
1788 }
1789
1790 /*
1791  * send an exit message to GDB
1792  */
1793 void gdbstub_exit(int status)
1794 {
1795         unsigned char checksum;
1796         unsigned char ch;
1797         int count;
1798
1799         gdbstub_busy = 1;
1800         output_buffer[0] = 'W';
1801         output_buffer[1] = hex_asc_hi(status);
1802         output_buffer[2] = hex_asc_lo(status);
1803         output_buffer[3] = 0;
1804
1805         gdbstub_io_tx_char('$');
1806         checksum = 0;
1807         count = 0;
1808
1809         while ((ch = output_buffer[count]) != 0) {
1810                 gdbstub_io_tx_char(ch);
1811                 checksum += ch;
1812                 count += 1;
1813         }
1814
1815         gdbstub_io_tx_char('#');
1816         gdbstub_io_tx_char(hex_asc_hi(checksum));
1817         gdbstub_io_tx_char(hex_asc_lo(checksum));
1818
1819         /* make sure the output is flushed, or else RedBoot might clobber it */
1820         gdbstub_io_tx_flush();
1821
1822         gdbstub_busy = 0;
1823 }
1824
1825 /*
1826  * initialise the GDB stub
1827  */
1828 asmlinkage void __init gdbstub_init(void)
1829 {
1830 #ifdef CONFIG_GDBSTUB_IMMEDIATE
1831         unsigned char ch;
1832         int ret;
1833 #endif
1834
1835         gdbstub_busy = 1;
1836
1837         printk(KERN_INFO "%s", gdbstub_banner);
1838
1839         gdbstub_io_init();
1840
1841         gdbstub_entry("--> gdbstub_init\n");
1842
1843         /* try to talk to GDB (or anyone insane enough to want to type GDB
1844          * protocol by hand) */
1845         gdbstub_io("### GDB Tx ACK\n");
1846         gdbstub_io_tx_char('+'); /* 'hello world' */
1847
1848 #ifdef CONFIG_GDBSTUB_IMMEDIATE
1849         gdbstub_printk("GDB Stub waiting for packet\n");
1850
1851         /* in case GDB is started before us, ACK any packets that are already
1852          * sitting there (presumably "$?#xx")
1853          */
1854         do { gdbstub_io_rx_char(&ch, 0); } while (ch != '$');
1855         do { gdbstub_io_rx_char(&ch, 0); } while (ch != '#');
1856         /* eat first csum byte */
1857         do { ret = gdbstub_io_rx_char(&ch, 0); } while (ret != 0);
1858         /* eat second csum byte */
1859         do { ret = gdbstub_io_rx_char(&ch, 0); } while (ret != 0);
1860
1861         gdbstub_io("### GDB Tx NAK\n");
1862         gdbstub_io_tx_char('-'); /* NAK it */
1863
1864 #else
1865         printk("GDB Stub ready\n");
1866 #endif
1867
1868         gdbstub_busy = 0;
1869         gdbstub_entry("<-- gdbstub_init\n");
1870 }
1871
1872 /*
1873  * register the console at a more appropriate time
1874  */
1875 #ifdef CONFIG_GDBSTUB_CONSOLE
1876 static int __init gdbstub_postinit(void)
1877 {
1878         printk(KERN_NOTICE "registering console\n");
1879         register_console(&gdbstub_console);
1880         return 0;
1881 }
1882
1883 __initcall(gdbstub_postinit);
1884 #endif
1885
1886 /*
1887  * handle character reception on GDB serial port
1888  * - jump into the GDB stub if BREAK is detected on the serial line
1889  */
1890 asmlinkage void gdbstub_rx_irq(struct pt_regs *regs, enum exception_code excep)
1891 {
1892         char ch;
1893         int ret;
1894
1895         gdbstub_entry("--> gdbstub_rx_irq\n");
1896
1897         do {
1898                 ret = gdbstub_io_rx_char(&ch, 1);
1899                 if (ret != -EIO && ret != -EAGAIN) {
1900                         if (ret != -EINTR)
1901                                 gdbstub_rx_unget = ch;
1902                         gdbstub(regs, excep);
1903                 }
1904         } while (ret != -EAGAIN);
1905
1906         gdbstub_entry("<-- gdbstub_rx_irq\n");
1907 }