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
);
122 return printk("<0x%p> [ %s + 0x%lx ]",
123 (void *)address
, name
, offset
);
130 write_unlock_irq(&tasklist_lock
);
132 /* we were unable to find this address anywhere */
133 return printk("[<0x%p>]", (void *)address
);
137 asmlinkage
void double_fault_c(struct pt_regs
*fp
)
139 printk(KERN_EMERG
"\n" KERN_EMERG
"Double Fault\n");
140 dump_bfin_regs(fp
, (void *)fp
->retx
);
141 panic("Double Fault - unrecoverable event\n");
145 asmlinkage
void trap_c(struct pt_regs
*fp
)
147 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
152 unsigned long trapnr
= fp
->seqstat
& SEQSTAT_EXCAUSE
;
155 # define CHK_DEBUGGER_TRAP() \
157 CHK_DEBUGGER(trapnr, sig, info.si_code, fp, ); \
159 # define CHK_DEBUGGER_TRAP_MAYBE() \
161 if (kgdb_connected) \
162 CHK_DEBUGGER_TRAP(); \
165 # define CHK_DEBUGGER_TRAP() do { } while (0)
166 # define CHK_DEBUGGER_TRAP_MAYBE() do { } while (0)
169 trace_buffer_save(j
);
171 /* trap_c() will be called for exceptions. During exceptions
172 * processing, the pc value should be set with retx value.
173 * With this change we can cleanup some code in signal.c- TODO
175 fp
->orig_pc
= fp
->retx
;
176 /* printk("exception: 0x%x, ipend=%x, reti=%x, retx=%x\n",
177 trapnr, fp->ipend, fp->pc, fp->retx); */
179 /* send the appropriate signal to the user program */
182 /* This table works in conjuction with the one in ./mach-common/entry.S
183 * Some exceptions are handled there (in assembly, in exception space)
184 * Some are handled here, (in C, in interrupt space)
185 * Some, like CPLB, are handled in both, where the normal path is
186 * handled in assembly/exception space, and the error path is handled
190 /* 0x00 - Linux Syscall, getting here is an error */
191 /* 0x01 - userspace gdb breakpoint, handled here */
193 info
.si_code
= TRAP_ILLTRAP
;
195 CHK_DEBUGGER_TRAP_MAYBE();
196 /* Check if this is a breakpoint in kernel space */
197 if (fp
->ipend
& 0xffc0)
202 case VEC_EXCPT02
: /* gdb connection */
203 info
.si_code
= TRAP_ILLTRAP
;
208 /* 0x02 - User Defined, Caught by default */
210 /* 0x03 - User Defined, userspace stack overflow */
212 info
.si_code
= SEGV_STACKFLOW
;
214 printk(KERN_EMERG EXC_0x03
);
217 /* 0x04 - User Defined, Caught by default */
218 /* 0x05 - User Defined, Caught by default */
219 /* 0x06 - User Defined, Caught by default */
220 /* 0x07 - User Defined, Caught by default */
221 /* 0x08 - User Defined, Caught by default */
222 /* 0x09 - User Defined, Caught by default */
223 /* 0x0A - User Defined, Caught by default */
224 /* 0x0B - User Defined, Caught by default */
225 /* 0x0C - User Defined, Caught by default */
226 /* 0x0D - User Defined, Caught by default */
227 /* 0x0E - User Defined, Caught by default */
228 /* 0x0F - User Defined, Caught by default */
229 /* 0x10 HW Single step, handled here */
231 info
.si_code
= TRAP_STEP
;
233 CHK_DEBUGGER_TRAP_MAYBE();
234 /* Check if this is a single step in kernel space */
235 if (fp
->ipend
& 0xffc0)
239 /* 0x11 - Trace Buffer Full, handled here */
241 info
.si_code
= TRAP_TRACEFLOW
;
243 printk(KERN_EMERG EXC_0x11
);
246 /* 0x12 - Reserved, Caught by default */
247 /* 0x13 - Reserved, Caught by default */
248 /* 0x14 - Reserved, Caught by default */
249 /* 0x15 - Reserved, Caught by default */
250 /* 0x16 - Reserved, Caught by default */
251 /* 0x17 - Reserved, Caught by default */
252 /* 0x18 - Reserved, Caught by default */
253 /* 0x19 - Reserved, Caught by default */
254 /* 0x1A - Reserved, Caught by default */
255 /* 0x1B - Reserved, Caught by default */
256 /* 0x1C - Reserved, Caught by default */
257 /* 0x1D - Reserved, Caught by default */
258 /* 0x1E - Reserved, Caught by default */
259 /* 0x1F - Reserved, Caught by default */
260 /* 0x20 - Reserved, Caught by default */
261 /* 0x21 - Undefined Instruction, handled here */
263 info
.si_code
= ILL_ILLOPC
;
265 printk(KERN_EMERG EXC_0x21
);
268 /* 0x22 - Illegal Instruction Combination, handled here */
270 info
.si_code
= ILL_ILLPARAOP
;
272 printk(KERN_EMERG EXC_0x22
);
275 /* 0x23 - Data CPLB Protection Violation,
276 normal case is handled in _cplb_hdr */
278 info
.si_code
= ILL_CPLB_VI
;
280 printk(KERN_EMERG EXC_0x23
);
283 /* 0x24 - Data access misaligned, handled here */
285 info
.si_code
= BUS_ADRALN
;
287 printk(KERN_EMERG EXC_0x24
);
290 /* 0x25 - Unrecoverable Event, handled here */
292 info
.si_code
= ILL_ILLEXCPT
;
294 printk(KERN_EMERG EXC_0x25
);
297 /* 0x26 - Data CPLB Miss, normal case is handled in _cplb_hdr,
298 error case is handled here */
300 info
.si_code
= BUS_ADRALN
;
302 printk(KERN_EMERG EXC_0x26
);
305 /* 0x27 - Data CPLB Multiple Hits - Linux Trap Zero, handled here */
307 info
.si_code
= ILL_CPLB_MULHIT
;
308 #ifdef CONFIG_DEBUG_HUNT_FOR_ZERO
310 printk(KERN_EMERG
"\n"
311 KERN_EMERG
"NULL pointer access (probably)\n");
314 printk(KERN_EMERG EXC_0x27
);
318 /* 0x28 - Emulation Watchpoint, handled here */
320 info
.si_code
= TRAP_WATCHPT
;
323 CHK_DEBUGGER_TRAP_MAYBE();
324 /* Check if this is a watchpoint in kernel space */
325 if (fp
->ipend
& 0xffc0)
330 /* 0x29 - Instruction fetch access error (535 only) */
331 case VEC_ISTRU_VL
: /* ADSP-BF535 only (MH) */
332 info
.si_code
= BUS_OPFETCH
;
334 printk(KERN_EMERG
"BF535: VEC_ISTRU_VL\n");
338 /* 0x29 - Reserved, Caught by default */
340 /* 0x2A - Instruction fetch misaligned, handled here */
342 info
.si_code
= BUS_ADRALN
;
344 printk(KERN_EMERG EXC_0x2A
);
347 /* 0x2B - Instruction CPLB protection Violation,
348 handled in _cplb_hdr */
350 info
.si_code
= ILL_CPLB_VI
;
352 printk(KERN_EMERG EXC_0x2B
);
355 /* 0x2C - Instruction CPLB miss, handled in _cplb_hdr */
357 info
.si_code
= ILL_CPLB_MISS
;
359 printk(KERN_EMERG EXC_0x2C
);
362 /* 0x2D - Instruction CPLB Multiple Hits, handled here */
363 case VEC_CPLB_I_MHIT
:
364 info
.si_code
= ILL_CPLB_MULHIT
;
365 #ifdef CONFIG_DEBUG_HUNT_FOR_ZERO
367 printk(KERN_EMERG
"\n\nJump to address 0 - 0x0fff\n");
370 printk(KERN_EMERG EXC_0x2D
);
374 /* 0x2E - Illegal use of Supervisor Resource, handled here */
376 info
.si_code
= ILL_PRVOPC
;
378 printk(KERN_EMERG EXC_0x2E
);
381 /* 0x2F - Reserved, Caught by default */
382 /* 0x30 - Reserved, Caught by default */
383 /* 0x31 - Reserved, Caught by default */
384 /* 0x32 - Reserved, Caught by default */
385 /* 0x33 - Reserved, Caught by default */
386 /* 0x34 - Reserved, Caught by default */
387 /* 0x35 - Reserved, Caught by default */
388 /* 0x36 - Reserved, Caught by default */
389 /* 0x37 - Reserved, Caught by default */
390 /* 0x38 - Reserved, Caught by default */
391 /* 0x39 - Reserved, Caught by default */
392 /* 0x3A - Reserved, Caught by default */
393 /* 0x3B - Reserved, Caught by default */
394 /* 0x3C - Reserved, Caught by default */
395 /* 0x3D - Reserved, Caught by default */
396 /* 0x3E - Reserved, Caught by default */
397 /* 0x3F - Reserved, Caught by default */
399 info
.si_code
= TRAP_ILLTRAP
;
401 printk(KERN_EMERG
"Caught Unhandled Exception, code = %08lx\n",
402 (fp
->seqstat
& SEQSTAT_EXCAUSE
));
407 if (sig
!= 0 && sig
!= SIGTRAP
) {
409 dump_bfin_regs(fp
, (void *)fp
->retx
);
410 dump_bfin_trace_buffer();
411 show_stack(current
, &stack
);
412 if (current
->mm
== NULL
)
413 panic("Kernel exception");
417 info
.si_addr
= (void *)fp
->pc
;
418 force_sig_info(sig
, &info
, current
);
420 /* if the address that we are about to return to is not valid, set it
421 * to a valid address, if we have a current application or panic
423 if (!(fp
->pc
<= physical_mem_end
424 #if L1_CODE_LENGTH != 0
425 || (fp
->pc
>= L1_CODE_START
&&
426 fp
->pc
<= (L1_CODE_START
+ L1_CODE_LENGTH
))
430 fp
->pc
= current
->mm
->start_code
;
433 "I can't return to memory that doesn't exist"
434 " - bad things happen\n");
435 panic("Help - I've fallen and can't get up\n");
439 trace_buffer_restore(j
);
443 /* Typical exception handling routines */
445 #define EXPAND_LEN ((1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN) * 256 - 1)
447 void dump_bfin_trace_buffer(void)
449 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
451 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND
455 trace_buffer_save(tflags
);
457 printk(KERN_EMERG
"Hardware Trace:\n");
459 if (likely(bfin_read_TBUFSTAT() & TBUFCNT
)) {
460 for (; bfin_read_TBUFSTAT() & TBUFCNT
; i
++) {
461 printk(KERN_EMERG
"%4i Target : ", i
);
462 printk_address((unsigned long)bfin_read_TBUF());
463 printk("\n" KERN_EMERG
" Source : ");
464 printk_address((unsigned long)bfin_read_TBUF());
469 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND
470 if (trace_buff_offset
)
471 index
= trace_buff_offset
/4 - 1;
475 j
= (1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN
) * 128;
477 printk(KERN_EMERG
"%4i Target : ", i
);
478 printk_address(software_trace_buff
[index
]);
482 printk("\n" KERN_EMERG
" Source : ");
483 printk_address(software_trace_buff
[index
]);
493 trace_buffer_restore(tflags
);
496 EXPORT_SYMBOL(dump_bfin_trace_buffer
);
498 static void show_trace(struct task_struct
*tsk
, unsigned long *sp
)
502 printk("\nCall Trace:");
503 #ifdef CONFIG_KALLSYMS
507 while (!kstack_end(sp
)) {
510 * If the address is either in the text segment of the
511 * kernel, or in the region which contains vmalloc'ed
512 * memory, it *may* be the address of a calling
513 * routine; if so, print it so that someone tracing
514 * down the cause of the crash will be able to figure
515 * out the call path that was taken.
517 if (kernel_text_address(addr
))
524 void show_stack(struct task_struct
*task
, unsigned long *stack
)
526 unsigned long *endstack
, addr
;
529 /* Cannot call dump_bfin_trace_buffer() here as show_stack() is
530 * called externally in some places in the kernel.
535 stack
= (unsigned long *)task
->thread
.ksp
;
537 stack
= (unsigned long *)&stack
;
540 addr
= (unsigned long)stack
;
541 endstack
= (unsigned long *)PAGE_ALIGN(addr
);
543 printk(KERN_EMERG
"Stack from %08lx:", (unsigned long)stack
);
544 for (i
= 0; i
< kstack_depth_to_print
; i
++) {
545 if (stack
+ 1 > endstack
)
548 printk("\n" KERN_EMERG
" ");
549 printk(" %08lx", *stack
++);
552 show_trace(task
, stack
);
555 void dump_stack(void)
558 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
561 trace_buffer_save(tflags
);
562 dump_bfin_trace_buffer();
563 show_stack(current
, &stack
);
564 trace_buffer_restore(tflags
);
567 EXPORT_SYMBOL(dump_stack
);
569 void dump_bfin_regs(struct pt_regs
*fp
, void *retaddr
)
572 printk(KERN_EMERG
"\n" KERN_EMERG
"CURRENT PROCESS:\n"
574 printk(KERN_EMERG
"COMM=%s PID=%d\n",
575 current
->comm
, current
->pid
);
578 (KERN_EMERG
"\n" KERN_EMERG
579 "No Valid pid - Either things are really messed up,"
580 " or you are in the kernel\n");
584 printk(KERN_EMERG
"TEXT = 0x%p-0x%p DATA = 0x%p-0x%p\n"
585 KERN_EMERG
"BSS = 0x%p-0x%p USER-STACK = 0x%p\n"
587 (void *)current
->mm
->start_code
,
588 (void *)current
->mm
->end_code
,
589 (void *)current
->mm
->start_data
,
590 (void *)current
->mm
->end_data
,
591 (void *)current
->mm
->end_data
,
592 (void *)current
->mm
->brk
,
593 (void *)current
->mm
->start_stack
);
596 printk(KERN_EMERG
"return address: [0x%p]; contents of:", retaddr
);
597 if (retaddr
!= 0 && retaddr
<= (void *)physical_mem_end
598 #if L1_CODE_LENGTH != 0
599 /* FIXME: Copy the code out of L1 Instruction SRAM through dma
601 && !(retaddr
>= (void *)L1_CODE_START
602 && retaddr
< (void *)(L1_CODE_START
+ L1_CODE_LENGTH
))
605 int i
= ((unsigned int)retaddr
& 0xFFFFFFF0) - 32;
606 unsigned short x
= 0;
607 for (; i
< ((unsigned int)retaddr
& 0xFFFFFFF0) + 32; i
+= 2) {
609 printk("\n" KERN_EMERG
"0x%08x: ", i
);
611 if (get_user(x
, (unsigned short *)i
))
613 #ifndef CONFIG_DEBUG_HWERR
614 /* If one of the last few instructions was a STI
615 * it is likely that the error occured awhile ago
616 * and we just noticed
618 if (x
>= 0x0040 && x
<= 0x0047 && i
<= 0)
619 panic("\n\nWARNING : You should reconfigure"
620 " the kernel to turn on\n"
621 " 'Hardware error interrupt"
623 " The rest of this error"
626 if (i
== (unsigned int)retaddr
)
631 printk("\n" KERN_EMERG
"\n");
634 "Cannot look at the [PC] for it is"
635 "in unreadable L1 SRAM - sorry\n");
639 "RETE: %08lx RETN: %08lx RETX: %08lx RETS: %08lx\n",
640 fp
->rete
, fp
->retn
, fp
->retx
, fp
->rets
);
641 printk(KERN_EMERG
"IPEND: %04lx SYSCFG: %04lx\n",
642 fp
->ipend
, fp
->syscfg
);
643 printk(KERN_EMERG
"SEQSTAT: %08lx SP: %08lx\n",
644 (long)fp
->seqstat
, (long)fp
);
645 printk(KERN_EMERG
"R0: %08lx R1: %08lx R2: %08lx R3: %08lx\n",
646 fp
->r0
, fp
->r1
, fp
->r2
, fp
->r3
);
647 printk(KERN_EMERG
"R4: %08lx R5: %08lx R6: %08lx R7: %08lx\n",
648 fp
->r4
, fp
->r5
, fp
->r6
, fp
->r7
);
649 printk(KERN_EMERG
"P0: %08lx P1: %08lx P2: %08lx P3: %08lx\n",
650 fp
->p0
, fp
->p1
, fp
->p2
, fp
->p3
);
652 "P4: %08lx P5: %08lx FP: %08lx\n",
653 fp
->p4
, fp
->p5
, fp
->fp
);
655 "A0.w: %08lx A0.x: %08lx A1.w: %08lx A1.x: %08lx\n",
656 fp
->a0w
, fp
->a0x
, fp
->a1w
, fp
->a1x
);
658 printk(KERN_EMERG
"LB0: %08lx LT0: %08lx LC0: %08lx\n",
659 fp
->lb0
, fp
->lt0
, fp
->lc0
);
660 printk(KERN_EMERG
"LB1: %08lx LT1: %08lx LC1: %08lx\n",
661 fp
->lb1
, fp
->lt1
, fp
->lc1
);
662 printk(KERN_EMERG
"B0: %08lx L0: %08lx M0: %08lx I0: %08lx\n",
663 fp
->b0
, fp
->l0
, fp
->m0
, fp
->i0
);
664 printk(KERN_EMERG
"B1: %08lx L1: %08lx M1: %08lx I1: %08lx\n",
665 fp
->b1
, fp
->l1
, fp
->m1
, fp
->i1
);
666 printk(KERN_EMERG
"B2: %08lx L2: %08lx M2: %08lx I2: %08lx\n",
667 fp
->b2
, fp
->l2
, fp
->m2
, fp
->i2
);
668 printk(KERN_EMERG
"B3: %08lx L3: %08lx M3: %08lx I3: %08lx\n",
669 fp
->b3
, fp
->l3
, fp
->m3
, fp
->i3
);
671 printk(KERN_EMERG
"\n" KERN_EMERG
"USP: %08lx ASTAT: %08lx\n",
673 if ((long)fp
->seqstat
& SEQSTAT_EXCAUSE
) {
674 printk(KERN_EMERG
"DCPLB_FAULT_ADDR=%p\n",
675 (void *)bfin_read_DCPLB_FAULT_ADDR());
676 printk(KERN_EMERG
"ICPLB_FAULT_ADDR=%p\n",
677 (void *)bfin_read_ICPLB_FAULT_ADDR());
683 #ifdef CONFIG_SYS_BFIN_SPINLOCK_L1
684 asmlinkage
int sys_bfin_spinlock(int *spinlock
)__attribute__((l1_text
));
687 asmlinkage
int sys_bfin_spinlock(int *spinlock
)
693 ret
= get_user(tmp
, spinlock
);
698 put_user(tmp
, spinlock
);
704 int bfin_request_exception(unsigned int exception
, void (*handler
)(void))
706 void (*curr_handler
)(void);
708 if (exception
> 0x3F)
711 curr_handler
= ex_table
[exception
];
713 if (curr_handler
!= ex_replaceable
)
716 ex_table
[exception
] = handler
;
720 EXPORT_SYMBOL(bfin_request_exception
);
722 int bfin_free_exception(unsigned int exception
, void (*handler
)(void))
724 void (*curr_handler
)(void);
726 if (exception
> 0x3F)
729 curr_handler
= ex_table
[exception
];
731 if (curr_handler
!= handler
)
734 ex_table
[exception
] = ex_replaceable
;
738 EXPORT_SYMBOL(bfin_free_exception
);
740 void panic_cplb_error(int cplb_panic
, struct pt_regs
*fp
)
742 switch (cplb_panic
) {
743 case CPLB_NO_UNLOCKED
:
744 printk(KERN_EMERG
"All CPLBs are locked\n");
748 case CPLB_NO_ADDR_MATCH
:
750 case CPLB_UNKNOWN_ERR
:
751 printk(KERN_EMERG
"Unknown CPLB Exception\n");
755 printk(KERN_EMERG
"DCPLB_FAULT_ADDR=%p\n", (void *)bfin_read_DCPLB_FAULT_ADDR());
756 printk(KERN_EMERG
"ICPLB_FAULT_ADDR=%p\n", (void *)bfin_read_ICPLB_FAULT_ADDR());
757 dump_bfin_regs(fp
, (void *)fp
->retx
);
759 panic("Unrecoverable event\n");