traps.c

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		CHK_DEBUGGER_TRAP();
		break;
	/* 0x2F - Reserved, Caught by default */
	/* 0x30 - Reserved, Caught by default */
	/* 0x31 - Reserved, Caught by default */
	/* 0x32 - Reserved, Caught by default */
	/* 0x33 - Reserved, Caught by default */
	/* 0x34 - Reserved, Caught by default */
	/* 0x35 - Reserved, Caught by default */
	/* 0x36 - Reserved, Caught by default */
	/* 0x37 - Reserved, Caught by default */
	/* 0x38 - Reserved, Caught by default */
	/* 0x39 - Reserved, Caught by default */
	/* 0x3A - Reserved, Caught by default */
	/* 0x3B - Reserved, Caught by default */
	/* 0x3C - Reserved, Caught by default */
	/* 0x3D - Reserved, Caught by default */
	/* 0x3E - Reserved, Caught by default */
	/* 0x3F - Reserved, Caught by default */
	default:
		info.si_code = TRAP_ILLTRAP;
		sig = SIGTRAP;
		printk(KERN_EMERG "Caught Unhandled Exception, code = %08lx\n",
			(fp->seqstat & SEQSTAT_EXCAUSE));
		CHK_DEBUGGER_TRAP();
		break;
	}

	BUG_ON(sig == 0);

	if (sig != SIGTRAP) {
		unsigned long stack;
		dump_bfin_process(fp);
		dump_bfin_mem((void *)fp->retx);
		show_regs(fp);

		/* Print out the trace buffer if it makes sense */
#ifndef CONFIG_DEBUG_BFIN_NO_KERN_HWTRACE
		if (trapnr == VEC_CPLB_I_M || trapnr == VEC_CPLB_M)
			printk(KERN_NOTICE "No trace since you do not have "
				"CONFIG_DEBUG_BFIN_NO_KERN_HWTRACE enabled\n"
				KERN_NOTICE "\n");
		else
#endif
			dump_bfin_trace_buffer();
		show_stack(current, &stack);
		if (oops_in_progress) {
#ifndef CONFIG_ACCESS_CHECK
			printk(KERN_EMERG "Please turn on "
			       "CONFIG_ACCESS_CHECK\n");
#endif
			panic("Kernel exception");
		}
	}

	info.si_signo = sig;
	info.si_errno = 0;
	info.si_addr = (void *)fp->pc;
	force_sig_info(sig, &info, current);

	/* Ensure that bad return addresses don't end up in an infinite
	 * loop, due to speculative loads/reads. This needs to be done after
	 * the signal has been sent.
	 */
	if (trapnr == VEC_CPLB_I_M && sig != SIGTRAP)
		fp->pc = SAFE_USER_INSTRUCTION;

	trace_buffer_restore(j);
	return;
}

/* Typical exception handling routines	*/

#define EXPAND_LEN ((1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN) * 256 - 1)

void dump_bfin_trace_buffer(void)
{
#ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
	int tflags, i = 0;
	char buf[150];
#ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND
	int j, index;
#endif

	trace_buffer_save(tflags);

	printk(KERN_NOTICE "Hardware Trace:\n");

	if (likely(bfin_read_TBUFSTAT() & TBUFCNT)) {
		for (; bfin_read_TBUFSTAT() & TBUFCNT; i++) {
			decode_address(buf, (unsigned long)bfin_read_TBUF());
			printk(KERN_NOTICE "%4i Target : %s\n", i, buf);
			decode_address(buf, (unsigned long)bfin_read_TBUF());
			printk(KERN_NOTICE "     Source : %s\n", buf);
		}
	}

#ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND
	if (trace_buff_offset)
		index = trace_buff_offset/4 - 1;
	else
		index = EXPAND_LEN;

	j = (1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN) * 128;
	while (j) {
		decode_address(buf, software_trace_buff[index]);
		printk(KERN_NOTICE "%4i Target : %s\n", i, buf);
		index -= 1;
		if (index < 0 )
			index = EXPAND_LEN;
		decode_address(buf, software_trace_buff[index]);
		printk(KERN_NOTICE "     Source : %s\n", buf);
		index -= 1;
		if (index < 0)
			index = EXPAND_LEN;
		j--;
		i++;
	}
#endif

	trace_buffer_restore(tflags);
#endif
}
EXPORT_SYMBOL(dump_bfin_trace_buffer);

static void show_trace(struct task_struct *tsk, unsigned long *sp)
{
	unsigned long addr;

	printk(KERN_NOTICE "\n" KERN_NOTICE "Call Trace:\n");

	while (!kstack_end(sp)) {
		addr = *sp++;
		/*
		 * If the address is either in the text segment of the
		 * kernel, or in the region which contains vmalloc'ed
		 * memory, it *may* be the address of a calling
		 * routine; if so, print it so that someone tracing
		 * down the cause of the crash will be able to figure
		 * out the call path that was taken.
		 */
		if (kernel_text_address(addr))
			print_ip_sym(addr);
	}

	printk(KERN_NOTICE "\n");
}

void show_stack(struct task_struct *task, unsigned long *stack)
{
	unsigned long *endstack, addr;
	int i;

	/* Cannot call dump_bfin_trace_buffer() here as show_stack() is
	 * called externally in some places in the kernel.
	 */

	if (!stack) {
		if (task)
			stack = (unsigned long *)task->thread.ksp;
		else
			stack = (unsigned long *)&stack;
	}

	addr = (unsigned long)stack;
	endstack = (unsigned long *)PAGE_ALIGN(addr);

	printk(KERN_NOTICE "Stack from %08lx:", (unsigned long)stack);
	for (i = 0; i < kstack_depth_to_print; i++) {
		if (stack + 1 > endstack)
			break;
		if (i % 8 == 0)
			printk("\n" KERN_NOTICE "       ");
		printk(" %08lx", *stack++);
	}
	printk("\n");

	show_trace(task, stack);
}

void dump_stack(void)
{
	unsigned long stack;
#ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
	int tflags;
#endif
	trace_buffer_save(tflags);
	dump_bfin_trace_buffer();
	show_stack(current, &stack);
	trace_buffer_restore(tflags);
}
EXPORT_SYMBOL(dump_stack);

void dump_bfin_process(struct pt_regs *fp)
{
	/* We should be able to look at fp->ipend, but we don't push it on the
	 * stack all the time, so do this until we fix that */
	unsigned int context = bfin_read_IPEND();

	if (oops_in_progress)
		printk(KERN_EMERG "Kernel OOPS in progress\n");

	if (context & 0x0020)
		printk(KERN_NOTICE "Deferred excecption or HW Error context\n");
	else if (context & 0x3FC0)
		printk(KERN_NOTICE "Interrupt context\n");
	else if (context & 0x4000)
		printk(KERN_NOTICE "Deferred Interrupt context\n");
	else if (context & 0x8000)
		printk(KERN_NOTICE "Kernel process context\n");

	if (current->pid && current->mm) {
		printk(KERN_NOTICE "CURRENT PROCESS:\n");
		printk(KERN_NOTICE "COMM=%s PID=%d\n",
			current->comm, current->pid);

		printk(KERN_NOTICE "TEXT = 0x%p-0x%p  DATA = 0x%p-0x%p\n"
			KERN_NOTICE "BSS = 0x%p-0x%p   USER-STACK = 0x%p\n"
			KERN_NOTICE "\n",
			(void *)current->mm->start_code,
			(void *)current->mm->end_code,
			(void *)current->mm->start_data,
			(void *)current->mm->end_data,
			(void *)current->mm->end_data,
			(void *)current->mm->brk,
			(void *)current->mm->start_stack);
	} else
		printk(KERN_NOTICE "\n" KERN_NOTICE
		     "No Valid process in current context\n");
}

void dump_bfin_mem(void *retaddr)
{

	if (retaddr >= (void *)FIXED_CODE_START  && retaddr < (void *)physical_mem_end
#if L1_CODE_LENGTH != 0
	    /* FIXME: Copy the code out of L1 Instruction SRAM through dma
	       memcpy.  */
	    && !(retaddr >= (void *)L1_CODE_START
	         && retaddr < (void *)(L1_CODE_START + L1_CODE_LENGTH))
#endif
	) {
		int i = ((unsigned int)retaddr & 0xFFFFFFF0) - 32;
		unsigned short x = 0;
		printk(KERN_NOTICE "return address: [0x%p]; contents of:", retaddr);
		for (; i < ((unsigned int)retaddr & 0xFFFFFFF0) + 32; i += 2) {
			if (!(i & 0xF))
				printk("\n" KERN_NOTICE "0x%08x: ", i);

			if (get_user(x, (unsigned short *)i))
				break;
#ifndef CONFIG_DEBUG_HWERR
			/* If one of the last few instructions was a STI
			 * it is likely that the error occured awhile ago
			 * and we just noticed. This only happens in kernel
			 * context, which should mean an oops is happening
			 */
			if (oops_in_progress && x >= 0x0040 && x <= 0x0047 && i <= 0)
				panic("\n\nWARNING : You should reconfigure"
					" the kernel to turn on\n"
					" 'Hardware error interrupt"
					" debugging'\n"
					" The rest of this error"
					" is meanless\n");
#endif
			if (i == (unsigned int)retaddr)
				printk("[%04x]", x);
			else
				printk(" %04x ", x);
		}
		printk("\n");
	} else
		printk("\n" KERN_NOTICE
			"Cannot look at the [PC] <%p> for it is"
			" in unreadable memory - sorry\n", retaddr);
}

void show_regs(struct pt_regs *fp)
{
	char buf [150];

	printk(KERN_NOTICE "\n" KERN_NOTICE "SEQUENCER STATUS:\n");
	printk(KERN_NOTICE " SEQSTAT: %08lx  IPEND: %04lx  SYSCFG: %04lx\n",
		(long)fp->seqstat, fp->ipend, fp->syscfg);

	decode_address(buf, fp->rete);
	printk(KERN_NOTICE " RETE: %s\n", buf);
	decode_address(buf, fp->retn);
	printk(KERN_NOTICE " RETN: %s\n", buf);
	decode_address(buf, fp->retx);
	printk(KERN_NOTICE " RETX: %s\n", buf);
	decode_address(buf, fp->rets);
	printk(KERN_NOTICE " RETS: %s\n", buf);
	decode_address(buf, fp->pc);
	printk(KERN_NOTICE " PC: %s\n", buf);

	if ((long)fp->seqstat & SEQSTAT_EXCAUSE) {
		decode_address(buf, bfin_read_DCPLB_FAULT_ADDR());
		printk(KERN_NOTICE "DCPLB_FAULT_ADDR: %s\n", buf);
		decode_address(buf, bfin_read_ICPLB_FAULT_ADDR());
		printk(KERN_NOTICE "ICPLB_FAULT_ADDR: %s\n", buf);
	}

	printk(KERN_NOTICE "\n" KERN_NOTICE "PROCESSOR STATE:\n");
	printk(KERN_NOTICE " R0 : %08lx    R1 : %08lx    R2 : %08lx    R3 : %08lx\n",
		fp->r0, fp->r1, fp->r2, fp->r3);
	printk(KERN_NOTICE " R4 : %08lx    R5 : %08lx    R6 : %08lx    R7 : %08lx\n",
		fp->r4, fp->r5, fp->r6, fp->r7);
	printk(KERN_NOTICE " P0 : %08lx    P1 : %08lx    P2 : %08lx    P3 : %08lx\n",
		fp->p0, fp->p1, fp->p2, fp->p3);
	printk(KERN_NOTICE " P4 : %08lx    P5 : %08lx    FP : %08lx    SP : %08lx\n",
		fp->p4, fp->p5, fp->fp, (long)fp);
	printk(KERN_NOTICE " LB0: %08lx    LT0: %08lx    LC0: %08lx\n",
		fp->lb0, fp->lt0, fp->lc0);
	printk(KERN_NOTICE " LB1: %08lx    LT1: %08lx    LC1: %08lx\n",
		fp->lb1, fp->lt1, fp->lc1);
	printk(KERN_NOTICE " B0 : %08lx    L0 : %08lx    M0 : %08lx    I0 : %08lx\n",
		fp->b0, fp->l0, fp->m0, fp->i0);
	printk(KERN_NOTICE " B1 : %08lx    L1 : %08lx    M1 : %08lx    I1 : %08lx\n",
		fp->b1, fp->l1, fp->m1, fp->i1);
	printk(KERN_NOTICE " B2 : %08lx    L2 : %08lx    M2 : %08lx    I2 : %08lx\n",
		fp->b2, fp->l2, fp->m2, fp->i2);
	printk(KERN_NOTICE " B3 : %08lx    L3 : %08lx    M3 : %08lx    I3 : %08lx\n",
		fp->b3, fp->l3, fp->m3, fp->i3);
	printk(KERN_NOTICE "A0.w: %08lx   A0.x: %08lx   A1.w: %08lx   A1.x: %08lx\n",
		fp->a0w, fp->a0x, fp->a1w, fp->a1x);

	printk(KERN_NOTICE "USP : %08lx  ASTAT: %08lx\n",
		rdusp(), fp->astat);

	printk(KERN_NOTICE "\n");
}

#ifdef CONFIG_SYS_BFIN_SPINLOCK_L1
asmlinkage int sys_bfin_spinlock(int *spinlock)__attribute__((l1_text));
#endif

asmlinkage int sys_bfin_spinlock(int *spinlock)
{
	int ret = 0;
	int tmp = 0;

	local_irq_disable();
	ret = get_user(tmp, spinlock);
	if (ret == 0) {
		if (tmp)
			ret = 1;
		tmp = 1;
		put_user(tmp, spinlock);
	}
	local_irq_enable();
	return ret;
}

int bfin_request_exception(unsigned int exception, void (*handler)(void))
{
	void (*curr_handler)(void);

	if (exception > 0x3F)
		return -EINVAL;

	curr_handler = ex_table[exception];

	if (curr_handler != ex_replaceable)
		return -EBUSY;

	ex_table[exception] = handler;

	return 0;
}
EXPORT_SYMBOL(bfin_request_exception);

int bfin_free_exception(unsigned int exception, void (*handler)(void))
{
	void (*curr_handler)(void);

	if (exception > 0x3F)
		return -EINVAL;

	curr_handler = ex_table[exception];

	if (curr_handler != handler)
		return -EBUSY;

	ex_table[exception] = ex_replaceable;

	return 0;
}
EXPORT_SYMBOL(bfin_free_exception);

void panic_cplb_error(int cplb_panic, struct pt_regs *fp)
{
	switch (cplb_panic) {
	case CPLB_NO_UNLOCKED:
		printk(KERN_EMERG "All CPLBs are locked\n");
		break;
	case CPLB_PROT_VIOL:
		return;
	case CPLB_NO_ADDR_MATCH:
		return;
	case CPLB_UNKNOWN_ERR:
		printk(KERN_EMERG "Unknown CPLB Exception\n");
		break;
	}

	oops_in_progress = 1;

	printk(KERN_EMERG "DCPLB_FAULT_ADDR=%p\n", (void *)bfin_read_DCPLB_FAULT_ADDR());
	printk(KERN_EMERG "ICPLB_FAULT_ADDR=%p\n", (void *)bfin_read_ICPLB_FAULT_ADDR());
	dump_bfin_process(fp);
	dump_bfin_mem((void *)fp->retx);
	show_regs(fp);
	dump_stack();
	panic("Unrecoverable event\n");
}