text: /*
   * linux/arch/powerpc/kernel/traps.c
   *
   * Copyright 2007 Freescale Semiconductor.
   * Copyright (C) 2003 Motorola
   * Modified by Xianghua Xiao(x.xiao@motorola.com)
   *
   * Copyright (C) 1995-1996  Gary Thomas (gdt@linuxppc.org)
   *
   * Modified by Cort Dougan (cort@cs.nmt.edu)
   * and Paul Mackerras (paulus@cs.anu.edu.au)
   *
   * (C) Copyright 2000
   * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   *
   * See file CREDITS for list of people who contributed to this
   * project.
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public License as
   * published by the Free Software Foundation; either version 2 of
   * the License, or (at your option) any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
   * MA 02111-1307 USA
   */
  
  /*
   * This file handles the architecture-dependent parts of hardware exceptions
   */
  
  #include <common.h>
  #include <command.h>
  #include <kgdb.h>
  #include <asm/processor.h>
  
  DECLARE_GLOBAL_DATA_PTR;
  
  /* Returns 0 if exception not found and fixup otherwise.  */
  extern unsigned long search_exception_table(unsigned long);
  
  /*
   * End of addressable memory.  This may be less than the actual
   * amount of memory on the system if we're unable to keep all
   * the memory mapped in.
   */
  extern ulong get_effective_memsize(void);
  #define END_OF_MEM (gd->bd->bi_memstart + get_effective_memsize())
  
  static __inline__ void set_tsr(unsigned long val)
  {
  	asm volatile("mtspr 0x150, %0" : : "r" (val));
  }
  
  static __inline__ unsigned long get_esr(void)
  {
  	unsigned long val;
  	asm volatile("mfspr %0, 0x03e" : "=r" (val) :);
  	return val;
  }
  
  #define ESR_MCI 0x80000000
  #define ESR_PIL 0x08000000
  #define ESR_PPR 0x04000000
  #define ESR_PTR 0x02000000
  #define ESR_DST 0x00800000
  #define ESR_DIZ 0x00400000
  #define ESR_U0F 0x00008000
  
  #if defined(CONFIG_CMD_BEDBUG)
  extern void do_bedbug_breakpoint(struct pt_regs *);
  #endif
  
  /*
   * Trap & Exception support
   */
  
  void
  print_backtrace(unsigned long *sp)
  {
  	int cnt = 0;
  	unsigned long i;
  
  	printf("Call backtrace: ");
  	while (sp) {
  		if ((uint)sp > END_OF_MEM)
  			break;
  
  		i = sp[1];
  		if (cnt++ % 7 == 0)
  			printf("\n");
  		printf("%08lX ", i);
  		if (cnt > 32) break;
  		sp = (unsigned long *)*sp;
  	}
  	printf("\n");
  }
  
  void show_regs(struct pt_regs * regs)
  {
  	int i;
  
  	printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DAR: %08lX\n",
  	       regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar);
  	printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n",
  	       regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0,
  	       regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0,
  	       regs->msr&MSR_IR ? 1 : 0,
  	       regs->msr&MSR_DR ? 1 : 0);
  
  	printf("\n");
  	for (i = 0;  i < 32;  i++) {
  		if ((i % 8) == 0)
  		{
  			printf("GPR%02d: ", i);
  		}
  
  		printf("%08lX ", regs->gpr[i]);
  		if ((i % 8) == 7)
  		{
  			printf("\n");
  		}
  	}
  }
  
  
  void
  _exception(int signr, struct pt_regs *regs)
  {
  	show_regs(regs);
  	print_backtrace((unsigned long *)regs->gpr[1]);
  	panic("Exception in kernel pc %lx signal %d",regs->nip,signr);
  }
  
  void
  CritcalInputException(struct pt_regs *regs)
  {
  	panic("Critical Input Exception");
  }
  
  int machinecheck_count = 0;
  int machinecheck_error = 0;
  void
  MachineCheckException(struct pt_regs *regs)
  {
  	unsigned long fixup;
  	unsigned int mcsr, mcsrr0, mcsrr1, mcar;
  
  	/* Probing PCI using config cycles cause this exception
  	 * when a device is not present.  Catch it and return to
  	 * the PCI exception handler.
  	 */
  	if ((fixup = search_exception_table(regs->nip)) != 0) {
  		regs->nip = fixup;
  		return;
  	}
  
  	mcsrr0 = mfspr(SPRN_MCSRR0);
  	mcsrr1 = mfspr(SPRN_MCSRR1);
  	mcsr = mfspr(SPRN_MCSR);
  	mcar = mfspr(SPRN_MCAR);
  
  	machinecheck_count++;
  	machinecheck_error=1;
  
  #if defined(CONFIG_CMD_KGDB)
  	if (debugger_exception_handler && (*debugger_exception_handler)(regs))
  		return;
  #endif
  
  	printf("Machine check in kernel mode.\n");
  	printf("Caused by (from mcsr): ");
  	printf("mcsr = 0x%08x\n", mcsr);
  	if (mcsr & 0x80000000)
  		printf("Machine check input pin\n");
  	if (mcsr & 0x40000000)
  		printf("Instruction cache parity error\n");
  	if (mcsr & 0x20000000)
  		printf("Data cache push parity error\n");
  	if (mcsr & 0x10000000)
  		printf("Data cache parity error\n");
  	if (mcsr & 0x00000080)
  		printf("Bus instruction address error\n");
  	if (mcsr & 0x00000040)
  		printf("Bus Read address error\n");
  	if (mcsr & 0x00000020)
  		printf("Bus Write address error\n");
  	if (mcsr & 0x00000010)
  		printf("Bus Instruction data bus error\n");
  	if (mcsr & 0x00000008)
  		printf("Bus Read data bus error\n");
  	if (mcsr & 0x00000004)
  		printf("Bus Write bus error\n");
  	if (mcsr & 0x00000002)
  		printf("Bus Instruction parity error\n");
  	if (mcsr & 0x00000001)
  		printf("Bus Read parity error\n");
  
  	show_regs(regs);
  	printf("MCSR=0x%08x \tMCSRR0=0x%08x \nMCSRR1=0x%08x \tMCAR=0x%08x\n",
  	       mcsr, mcsrr0, mcsrr1, mcar);
  	print_backtrace((unsigned long *)regs->gpr[1]);
  	if (machinecheck_count > 10) {
  		panic("machine check count too high\n");
  	}
  
  	if (machinecheck_count > 1) {
  		regs->nip += 4; /* skip offending instruction */
  		printf("Skipping current instr, Returning to 0x%08lx\n",
  		       regs->nip);
  	} else {
  		printf("Returning back to 0x%08lx\n",regs->nip);
  	}
  }
  
  void
  AlignmentException(struct pt_regs *regs)
  {
  #if defined(CONFIG_CMD_KGDB)
  	if (debugger_exception_handler && (*debugger_exception_handler)(regs))
  		return;
  #endif
  
  	show_regs(regs);
  	print_backtrace((unsigned long *)regs->gpr[1]);
  	panic("Alignment Exception");
  }
  
  void
  ProgramCheckException(struct pt_regs *regs)
  {
  	long esr_val;
  
  #if defined(CONFIG_CMD_KGDB)
  	if (debugger_exception_handler && (*debugger_exception_handler)(regs))
  		return;
  #endif
  
  	show_regs(regs);
  
  	esr_val = get_esr();
  	if( esr_val & ESR_PIL )
  		printf( "** Illegal Instruction **\n" );
  	else if( esr_val & ESR_PPR )
  		printf( "** Privileged Instruction **\n" );
  	else if( esr_val & ESR_PTR )
  		printf( "** Trap Instruction **\n" );
  
  	print_backtrace((unsigned long *)regs->gpr[1]);
  	panic("Program Check Exception");
  }
  
  void
  PITException(struct pt_regs *regs)
  {
  	/*
  	 * Reset PIT interrupt
  	 */
  	set_tsr(0x0c000000);
  
  	/*
  	 * Call timer_interrupt routine in interrupts.c
  	 */
  	timer_interrupt(NULL);
  }
  
  
  void
  UnknownException(struct pt_regs *regs)
  {
  #if defined(CONFIG_CMD_KGDB)
  	if (debugger_exception_handler && (*debugger_exception_handler)(regs))
  		return;
  #endif
  
  	printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
  	       regs->nip, regs->msr, regs->trap);
  	_exception(0, regs);
  }
  
  void
  ExtIntException(struct pt_regs *regs)
  {
  	volatile ccsr_pic_t *pic = (void *)(CONFIG_SYS_MPC8xxx_PIC_ADDR);
  
  	uint vect;
  
  #if defined(CONFIG_CMD_KGDB)
  	if (debugger_exception_handler && (*debugger_exception_handler)(regs))
  		return;
  #endif
  
  	printf("External Interrupt Exception at PC: %lx, SR: %lx, vector=%lx",
  	       regs->nip, regs->msr, regs->trap);
  	vect = pic->iack0;
  	printf(" irq IACK0@%05x=%d\n",(int)&pic->iack0,vect);
  	show_regs(regs);
  	print_backtrace((unsigned long *)regs->gpr[1]);
  }
  
  void
  DebugException(struct pt_regs *regs)
  {
  	printf("Debugger trap at @ %lx\n", regs->nip );
  	show_regs(regs);
  #if defined(CONFIG_CMD_BEDBUG)
  	do_bedbug_breakpoint( regs );
  #endif
  }
  
  /* Probe an address by reading.	 If not present, return -1, otherwise
   * return 0.
   */
  int
  addr_probe(uint *addr)
  {
  	return 0;
  }
  