2 * File: arch/blackfin/kernel/traps.c
4 * Author: Hamish Macdonald
7 * Description: uses S/W interrupt 15 for the system calls
10 * Copyright 2004-2006 Analog Devices Inc.
12 * Bugs: Enter bugs at http://blackfin.uclinux.org/
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
24 * You should have received a copy of the GNU General Public License
25 * along with this program; if not, see the file COPYING, or write
26 * to the Free Software Foundation, Inc.,
27 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
30 #include <linux/uaccess.h>
31 #include <linux/interrupt.h>
32 #include <linux/module.h>
33 #include <linux/kallsyms.h>
35 #include <asm/traps.h>
36 #include <asm/cacheflush.h>
37 #include <asm/blackfin.h>
38 #include <asm/irq_handler.h>
39 #include <asm/trace.h>
42 # include <linux/debugger.h>
43 # include <linux/kgdb.h>
46 /* Initiate the event table handler */
47 void __init
trap_init(void)
50 bfin_write_EVT3(trap
);
54 int kstack_depth_to_print
= 48;
56 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
57 static int printk_address(unsigned long address
)
59 struct vm_list_struct
*vml
;
60 struct task_struct
*p
;
64 #ifdef CONFIG_KALLSYMS
65 unsigned long symsize
;
71 /* look up the address and see if we are in kernel space */
72 symname
= kallsyms_lookup(address
, &symsize
, &offset
, &modname
, namebuf
);
75 /* yeah! kernel space! */
78 return printk("<0x%p> { %s%s%s%s + 0x%lx }",
79 (void *)address
, delim
, modname
, delim
, symname
,
80 (unsigned long)offset
);
85 /* looks like we're off in user-land, so let's walk all the
86 * mappings of all our processes and see if we can't be a whee
89 write_lock_irq(&tasklist_lock
);
95 vml
= mm
->context
.vmlist
;
97 struct vm_area_struct
*vma
= vml
->vma
;
99 if (address
>= vma
->vm_start
&& address
< vma
->vm_end
) {
100 char *name
= p
->comm
;
101 struct file
*file
= vma
->vm_file
;
104 name
= d_path(file
->f_dentry
,
110 /* FLAT does not have its text aligned to the start of
111 * the map while FDPIC ELF does ...
114 (address
> current
->mm
->start_code
) &&
115 (address
< current
->mm
->end_code
))
116 offset
= address
- current
->mm
->start_code
;
118 offset
= (address
- vma
->vm_start
) + (vma
->vm_pgoff
<< PAGE_SHIFT
);
120 write_unlock_irq(&tasklist_lock
);
121 return printk("<0x%p> [ %s + 0x%lx ]",
122 (void *)address
, name
, offset
);
128 write_unlock_irq(&tasklist_lock
);
130 /* we were unable to find this address anywhere */
131 return printk("[<0x%p>]", (void *)address
);
135 asmlinkage
void trap_c(struct pt_regs
*fp
)
137 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
142 unsigned long trapnr
= fp
->seqstat
& SEQSTAT_EXCAUSE
;
145 # define CHK_DEBUGGER_TRAP() \
147 CHK_DEBUGGER(trapnr, sig, info.si_code, fp, ); \
149 # define CHK_DEBUGGER_TRAP_MAYBE() \
151 if (kgdb_connected) \
152 CHK_DEBUGGER_TRAP(); \
155 # define CHK_DEBUGGER_TRAP() do { } while (0)
156 # define CHK_DEBUGGER_TRAP_MAYBE() do { } while (0)
159 trace_buffer_save(j
);
161 /* trap_c() will be called for exceptions. During exceptions
162 * processing, the pc value should be set with retx value.
163 * With this change we can cleanup some code in signal.c- TODO
165 fp
->orig_pc
= fp
->retx
;
166 /* printk("exception: 0x%x, ipend=%x, reti=%x, retx=%x\n",
167 trapnr, fp->ipend, fp->pc, fp->retx); */
169 /* send the appropriate signal to the user program */
172 /* This table works in conjuction with the one in ./mach-common/entry.S
173 * Some exceptions are handled there (in assembly, in exception space)
174 * Some are handled here, (in C, in interrupt space)
175 * Some, like CPLB, are handled in both, where the normal path is
176 * handled in assembly/exception space, and the error path is handled
180 /* 0x00 - Linux Syscall, getting here is an error */
181 /* 0x01 - userspace gdb breakpoint, handled here */
183 info
.si_code
= TRAP_ILLTRAP
;
185 CHK_DEBUGGER_TRAP_MAYBE();
186 /* Check if this is a breakpoint in kernel space */
187 if (fp
->ipend
& 0xffc0)
192 case VEC_EXCPT02
: /* gdb connection */
193 info
.si_code
= TRAP_ILLTRAP
;
198 /* 0x02 - User Defined, Caught by default */
200 /* 0x03 - User Defined, userspace stack overflow */
202 info
.si_code
= SEGV_STACKFLOW
;
204 printk(KERN_EMERG EXC_0x03
);
207 /* 0x04 - User Defined, Caught by default */
208 /* 0x05 - User Defined, Caught by default */
209 /* 0x06 - User Defined, Caught by default */
210 /* 0x07 - User Defined, Caught by default */
211 /* 0x08 - User Defined, Caught by default */
212 /* 0x09 - User Defined, Caught by default */
213 /* 0x0A - User Defined, Caught by default */
214 /* 0x0B - User Defined, Caught by default */
215 /* 0x0C - User Defined, Caught by default */
216 /* 0x0D - User Defined, Caught by default */
217 /* 0x0E - User Defined, Caught by default */
218 /* 0x0F - User Defined, Caught by default */
219 /* 0x10 HW Single step, handled here */
221 info
.si_code
= TRAP_STEP
;
223 CHK_DEBUGGER_TRAP_MAYBE();
224 /* Check if this is a single step in kernel space */
225 if (fp
->ipend
& 0xffc0)
229 /* 0x11 - Trace Buffer Full, handled here */
231 info
.si_code
= TRAP_TRACEFLOW
;
233 printk(KERN_EMERG EXC_0x11
);
236 /* 0x12 - Reserved, Caught by default */
237 /* 0x13 - Reserved, Caught by default */
238 /* 0x14 - Reserved, Caught by default */
239 /* 0x15 - Reserved, Caught by default */
240 /* 0x16 - Reserved, Caught by default */
241 /* 0x17 - Reserved, Caught by default */
242 /* 0x18 - Reserved, Caught by default */
243 /* 0x19 - Reserved, Caught by default */
244 /* 0x1A - Reserved, Caught by default */
245 /* 0x1B - Reserved, Caught by default */
246 /* 0x1C - Reserved, Caught by default */
247 /* 0x1D - Reserved, Caught by default */
248 /* 0x1E - Reserved, Caught by default */
249 /* 0x1F - Reserved, Caught by default */
250 /* 0x20 - Reserved, Caught by default */
251 /* 0x21 - Undefined Instruction, handled here */
253 info
.si_code
= ILL_ILLOPC
;
255 printk(KERN_EMERG EXC_0x21
);
258 /* 0x22 - Illegal Instruction Combination, handled here */
260 info
.si_code
= ILL_ILLPARAOP
;
262 printk(KERN_EMERG EXC_0x22
);
265 /* 0x23 - Data CPLB Protection Violation,
266 normal case is handled in _cplb_hdr */
268 info
.si_code
= ILL_CPLB_VI
;
270 printk(KERN_EMERG EXC_0x23
);
273 /* 0x24 - Data access misaligned, handled here */
275 info
.si_code
= BUS_ADRALN
;
277 printk(KERN_EMERG EXC_0x24
);
280 /* 0x25 - Unrecoverable Event, handled here */
282 info
.si_code
= ILL_ILLEXCPT
;
284 printk(KERN_EMERG EXC_0x25
);
287 /* 0x26 - Data CPLB Miss, normal case is handled in _cplb_hdr,
288 error case is handled here */
290 info
.si_code
= BUS_ADRALN
;
292 printk(KERN_EMERG EXC_0x26
);
295 /* 0x27 - Data CPLB Multiple Hits - Linux Trap Zero, handled here */
297 info
.si_code
= ILL_CPLB_MULHIT
;
298 #ifdef CONFIG_DEBUG_HUNT_FOR_ZERO
300 printk(KERN_EMERG
"\n"
301 KERN_EMERG
"NULL pointer access (probably)\n");
304 printk(KERN_EMERG EXC_0x27
);
308 /* 0x28 - Emulation Watchpoint, handled here */
310 info
.si_code
= TRAP_WATCHPT
;
313 CHK_DEBUGGER_TRAP_MAYBE();
314 /* Check if this is a watchpoint in kernel space */
315 if (fp
->ipend
& 0xffc0)
320 /* 0x29 - Instruction fetch access error (535 only) */
321 case VEC_ISTRU_VL
: /* ADSP-BF535 only (MH) */
322 info
.si_code
= BUS_OPFETCH
;
324 printk(KERN_EMERG
"BF535: VEC_ISTRU_VL\n");
328 /* 0x29 - Reserved, Caught by default */
330 /* 0x2A - Instruction fetch misaligned, handled here */
332 info
.si_code
= BUS_ADRALN
;
334 printk(KERN_EMERG EXC_0x2A
);
337 /* 0x2B - Instruction CPLB protection Violation,
338 handled in _cplb_hdr */
340 info
.si_code
= ILL_CPLB_VI
;
342 printk(KERN_EMERG EXC_0x2B
);
345 /* 0x2C - Instruction CPLB miss, handled in _cplb_hdr */
347 info
.si_code
= ILL_CPLB_MISS
;
349 printk(KERN_EMERG EXC_0x2C
);
352 /* 0x2D - Instruction CPLB Multiple Hits, handled here */
353 case VEC_CPLB_I_MHIT
:
354 info
.si_code
= ILL_CPLB_MULHIT
;
355 #ifdef CONFIG_DEBUG_HUNT_FOR_ZERO
357 printk(KERN_EMERG
"\n\nJump to address 0 - 0x0fff\n");
360 printk(KERN_EMERG EXC_0x2D
);
364 /* 0x2E - Illegal use of Supervisor Resource, handled here */
366 info
.si_code
= ILL_PRVOPC
;
368 printk(KERN_EMERG EXC_0x2E
);
371 /* 0x2F - Reserved, Caught by default */
372 /* 0x30 - Reserved, Caught by default */
373 /* 0x31 - Reserved, Caught by default */
374 /* 0x32 - Reserved, Caught by default */
375 /* 0x33 - Reserved, Caught by default */
376 /* 0x34 - Reserved, Caught by default */
377 /* 0x35 - Reserved, Caught by default */
378 /* 0x36 - Reserved, Caught by default */
379 /* 0x37 - Reserved, Caught by default */
380 /* 0x38 - Reserved, Caught by default */
381 /* 0x39 - Reserved, Caught by default */
382 /* 0x3A - Reserved, Caught by default */
383 /* 0x3B - Reserved, Caught by default */
384 /* 0x3C - Reserved, Caught by default */
385 /* 0x3D - Reserved, Caught by default */
386 /* 0x3E - Reserved, Caught by default */
387 /* 0x3F - Reserved, Caught by default */
389 info
.si_code
= TRAP_ILLTRAP
;
391 printk(KERN_EMERG
"Caught Unhandled Exception, code = %08lx\n",
392 (fp
->seqstat
& SEQSTAT_EXCAUSE
));
399 info
.si_addr
= (void *)fp
->pc
;
400 force_sig_info(sig
, &info
, current
);
401 if (sig
!= 0 && sig
!= SIGTRAP
) {
403 dump_bfin_regs(fp
, (void *)fp
->retx
);
404 dump_bfin_trace_buffer();
405 show_stack(current
, &stack
);
406 if (current
->mm
== NULL
)
407 panic("Kernel exception");
410 /* if the address that we are about to return to is not valid, set it
411 * to a valid address, if we have a current application or panic
413 if (!(fp
->pc
<= physical_mem_end
414 #if L1_CODE_LENGTH != 0
415 || (fp
->pc
>= L1_CODE_START
&&
416 fp
->pc
<= (L1_CODE_START
+ L1_CODE_LENGTH
))
420 fp
->pc
= current
->mm
->start_code
;
423 "I can't return to memory that doesn't exist"
424 " - bad things happen\n");
425 panic("Help - I've fallen and can't get up\n");
429 trace_buffer_restore(j
);
433 /* Typical exception handling routines */
435 #define EXPAND_LEN ((1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN) * 256 - 1)
437 void dump_bfin_trace_buffer(void)
439 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
441 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND
445 trace_buffer_save(tflags
);
447 printk(KERN_EMERG
"Hardware Trace:\n");
449 if (likely(bfin_read_TBUFSTAT() & TBUFCNT
)) {
450 for (; bfin_read_TBUFSTAT() & TBUFCNT
; i
++) {
451 printk(KERN_EMERG
"%4i Target : ", i
);
452 printk_address((unsigned long)bfin_read_TBUF());
453 printk("\n" KERN_EMERG
" Source : ");
454 printk_address((unsigned long)bfin_read_TBUF());
459 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND
460 if (trace_buff_offset
)
461 index
= trace_buff_offset
/4 - 1;
465 j
= (1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN
) * 128;
467 printk(KERN_EMERG
"%4i Target : ", i
);
468 printk_address(software_trace_buff
[index
]);
472 printk("\n" KERN_EMERG
" Source : ");
473 printk_address(software_trace_buff
[index
]);
483 trace_buffer_restore(tflags
);
486 EXPORT_SYMBOL(dump_bfin_trace_buffer
);
488 static void show_trace(struct task_struct
*tsk
, unsigned long *sp
)
492 printk("\nCall Trace:");
493 #ifdef CONFIG_KALLSYMS
497 while (!kstack_end(sp
)) {
500 * If the address is either in the text segment of the
501 * kernel, or in the region which contains vmalloc'ed
502 * memory, it *may* be the address of a calling
503 * routine; if so, print it so that someone tracing
504 * down the cause of the crash will be able to figure
505 * out the call path that was taken.
507 if (kernel_text_address(addr
))
514 void show_stack(struct task_struct
*task
, unsigned long *stack
)
516 unsigned long *endstack
, addr
;
519 /* Cannot call dump_bfin_trace_buffer() here as show_stack() is
520 * called externally in some places in the kernel.
525 stack
= (unsigned long *)task
->thread
.ksp
;
527 stack
= (unsigned long *)&stack
;
530 addr
= (unsigned long)stack
;
531 endstack
= (unsigned long *)PAGE_ALIGN(addr
);
533 printk(KERN_EMERG
"Stack from %08lx:", (unsigned long)stack
);
534 for (i
= 0; i
< kstack_depth_to_print
; i
++) {
535 if (stack
+ 1 > endstack
)
538 printk("\n" KERN_EMERG
" ");
539 printk(" %08lx", *stack
++);
542 show_trace(task
, stack
);
545 void dump_stack(void)
548 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
551 trace_buffer_save(tflags
);
552 dump_bfin_trace_buffer();
553 show_stack(current
, &stack
);
554 trace_buffer_restore(tflags
);
557 EXPORT_SYMBOL(dump_stack
);
559 void dump_bfin_regs(struct pt_regs
*fp
, void *retaddr
)
562 printk(KERN_EMERG
"\n" KERN_EMERG
"CURRENT PROCESS:\n"
564 printk(KERN_EMERG
"COMM=%s PID=%d\n",
565 current
->comm
, current
->pid
);
568 (KERN_EMERG
"\n" KERN_EMERG
569 "No Valid pid - Either things are really messed up,"
570 " or you are in the kernel\n");
574 printk(KERN_EMERG
"TEXT = 0x%p-0x%p DATA = 0x%p-0x%p\n"
575 KERN_EMERG
"BSS = 0x%p-0x%p USER-STACK = 0x%p\n"
577 (void *)current
->mm
->start_code
,
578 (void *)current
->mm
->end_code
,
579 (void *)current
->mm
->start_data
,
580 (void *)current
->mm
->end_data
,
581 (void *)current
->mm
->end_data
,
582 (void *)current
->mm
->brk
,
583 (void *)current
->mm
->start_stack
);
586 printk(KERN_EMERG
"return address: [0x%p]; contents of:", retaddr
);
587 if (retaddr
!= 0 && retaddr
<= (void *)physical_mem_end
588 #if L1_CODE_LENGTH != 0
589 /* FIXME: Copy the code out of L1 Instruction SRAM through dma
591 && !(retaddr
>= (void *)L1_CODE_START
592 && retaddr
< (void *)(L1_CODE_START
+ L1_CODE_LENGTH
))
595 int i
= ((unsigned int)retaddr
& 0xFFFFFFF0) - 32;
596 unsigned short x
= 0;
597 for (; i
< ((unsigned int)retaddr
& 0xFFFFFFF0) + 32; i
+= 2) {
599 printk("\n" KERN_EMERG
"0x%08x: ", i
);
601 if (get_user(x
, (unsigned short *)i
))
603 #ifndef CONFIG_DEBUG_HWERR
604 /* If one of the last few instructions was a STI
605 * it is likely that the error occured awhile ago
606 * and we just noticed
608 if (x
>= 0x0040 && x
<= 0x0047 && i
<= 0)
609 panic("\n\nWARNING : You should reconfigure"
610 " the kernel to turn on\n"
611 " 'Hardware error interrupt"
613 " The rest of this error"
616 if (i
== (unsigned int)retaddr
)
621 printk("\n" KERN_EMERG
"\n");
624 "Cannot look at the [PC] for it is"
625 "in unreadable L1 SRAM - sorry\n");
629 "RETE: %08lx RETN: %08lx RETX: %08lx RETS: %08lx\n",
630 fp
->rete
, fp
->retn
, fp
->retx
, fp
->rets
);
631 printk(KERN_EMERG
"IPEND: %04lx SYSCFG: %04lx\n",
632 fp
->ipend
, fp
->syscfg
);
633 printk(KERN_EMERG
"SEQSTAT: %08lx SP: %08lx\n",
634 (long)fp
->seqstat
, (long)fp
);
635 printk(KERN_EMERG
"R0: %08lx R1: %08lx R2: %08lx R3: %08lx\n",
636 fp
->r0
, fp
->r1
, fp
->r2
, fp
->r3
);
637 printk(KERN_EMERG
"R4: %08lx R5: %08lx R6: %08lx R7: %08lx\n",
638 fp
->r4
, fp
->r5
, fp
->r6
, fp
->r7
);
639 printk(KERN_EMERG
"P0: %08lx P1: %08lx P2: %08lx P3: %08lx\n",
640 fp
->p0
, fp
->p1
, fp
->p2
, fp
->p3
);
642 "P4: %08lx P5: %08lx FP: %08lx\n",
643 fp
->p4
, fp
->p5
, fp
->fp
);
645 "A0.w: %08lx A0.x: %08lx A1.w: %08lx A1.x: %08lx\n",
646 fp
->a0w
, fp
->a0x
, fp
->a1w
, fp
->a1x
);
648 printk(KERN_EMERG
"LB0: %08lx LT0: %08lx LC0: %08lx\n",
649 fp
->lb0
, fp
->lt0
, fp
->lc0
);
650 printk(KERN_EMERG
"LB1: %08lx LT1: %08lx LC1: %08lx\n",
651 fp
->lb1
, fp
->lt1
, fp
->lc1
);
652 printk(KERN_EMERG
"B0: %08lx L0: %08lx M0: %08lx I0: %08lx\n",
653 fp
->b0
, fp
->l0
, fp
->m0
, fp
->i0
);
654 printk(KERN_EMERG
"B1: %08lx L1: %08lx M1: %08lx I1: %08lx\n",
655 fp
->b1
, fp
->l1
, fp
->m1
, fp
->i1
);
656 printk(KERN_EMERG
"B2: %08lx L2: %08lx M2: %08lx I2: %08lx\n",
657 fp
->b2
, fp
->l2
, fp
->m2
, fp
->i2
);
658 printk(KERN_EMERG
"B3: %08lx L3: %08lx M3: %08lx I3: %08lx\n",
659 fp
->b3
, fp
->l3
, fp
->m3
, fp
->i3
);
661 printk(KERN_EMERG
"\n" KERN_EMERG
"USP: %08lx ASTAT: %08lx\n",
663 if ((long)fp
->seqstat
& SEQSTAT_EXCAUSE
) {
664 printk(KERN_EMERG
"DCPLB_FAULT_ADDR=%p\n",
665 (void *)bfin_read_DCPLB_FAULT_ADDR());
666 printk(KERN_EMERG
"ICPLB_FAULT_ADDR=%p\n",
667 (void *)bfin_read_ICPLB_FAULT_ADDR());
673 #ifdef CONFIG_SYS_BFIN_SPINLOCK_L1
674 asmlinkage
int sys_bfin_spinlock(int *spinlock
)__attribute__((l1_text
));
677 asmlinkage
int sys_bfin_spinlock(int *spinlock
)
683 ret
= get_user(tmp
, spinlock
);
688 put_user(tmp
, spinlock
);
694 int bfin_request_exception(unsigned int exception
, void (*handler
)(void))
696 void (*curr_handler
)(void);
698 if (exception
> 0x3F)
701 curr_handler
= ex_table
[exception
];
703 if (curr_handler
!= ex_replaceable
)
706 ex_table
[exception
] = handler
;
710 EXPORT_SYMBOL(bfin_request_exception
);
712 int bfin_free_exception(unsigned int exception
, void (*handler
)(void))
714 void (*curr_handler
)(void);
716 if (exception
> 0x3F)
719 curr_handler
= ex_table
[exception
];
721 if (curr_handler
!= handler
)
724 ex_table
[exception
] = ex_replaceable
;
728 EXPORT_SYMBOL(bfin_free_exception
);
730 void panic_cplb_error(int cplb_panic
, struct pt_regs
*fp
)
732 switch (cplb_panic
) {
733 case CPLB_NO_UNLOCKED
:
734 printk(KERN_EMERG
"All CPLBs are locked\n");
738 case CPLB_NO_ADDR_MATCH
:
740 case CPLB_UNKNOWN_ERR
:
741 printk(KERN_EMERG
"Unknown CPLB Exception\n");
745 printk(KERN_EMERG
"DCPLB_FAULT_ADDR=%p\n", (void *)bfin_read_DCPLB_FAULT_ADDR());
746 printk(KERN_EMERG
"ICPLB_FAULT_ADDR=%p\n", (void *)bfin_read_ICPLB_FAULT_ADDR());
747 dump_bfin_regs(fp
, (void *)fp
->retx
);
749 panic("Unrecoverable event\n");