/* * Copyright 2010 Tilera Corporation. All Rights Reserved. * *   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, version 2. * *   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, GOOD TITLE or *   NON INFRINGEMENT.  See the GNU General Public License for *   more details. */ #ifndef _ASM_TILE_BACKTRACE_H#define _ASM_TILE_BACKTRACE_H #include <linux/types.h> /* Reads 'size' bytes from 'address' and writes the data to 'result'. * Returns true if successful, else false (e.g. memory not readable). */typedef bool (*BacktraceMemoryReader)(void *result,				      unsigned long address,				      unsigned int size,				      void *extra); typedef struct {	/* Current PC. */	unsigned long pc; 	/* Current stack pointer value. */	unsigned long sp; 	/* Current frame pointer value (i.e. caller's stack pointer) */	unsigned long fp; 	/* Internal use only: caller's PC for first frame. */	unsigned long initial_frame_caller_pc; 	/* Internal use only: callback to read memory. */	BacktraceMemoryReader read_memory_func; 	/* Internal use only: arbitrary argument to read_memory_func. */	void *read_memory_func_extra; } BacktraceIterator;  typedef enum { 	/* We have no idea what the caller's pc is. */	PC_LOC_UNKNOWN, 	/* The caller's pc is currently in lr. */	PC_LOC_IN_LR, 	/* The caller's pc can be found by dereferencing the caller's sp. */	PC_LOC_ON_STACK } CallerPCLocation;  typedef enum { 	/* We have no idea what the caller's sp is. */	SP_LOC_UNKNOWN, 	/* The caller's sp is currently in r52. */	SP_LOC_IN_R52, 	/* The caller's sp can be found by adding a certain constant	 * to the current value of sp.	 */	SP_LOC_OFFSET } CallerSPLocation;  /* Bit values ORed into CALLER_* values for info ops. */enum {	/* Setting the low bit on any of these values means the info op	 * applies only to one bundle ago.	 */	ONE_BUNDLE_AGO_FLAG = 1, 	/* Setting this bit on a CALLER_SP_* value means the PC is in LR.	 * If not set, PC is on the stack.	 */	PC_IN_LR_FLAG = 2, 	/* This many of the low bits of a CALLER_SP_* value are for the	 * flag bits above.	 */	NUM_INFO_OP_FLAGS = 2, 	/* We cannot have one in the memory pipe so this is the maximum. */	MAX_INFO_OPS_PER_BUNDLE = 2};  /* Internal constants used to define 'info' operands. */enum {	/* 0 and 1 are reserved, as are all negative numbers. */ 	CALLER_UNKNOWN_BASE = 2, 	CALLER_SP_IN_R52_BASE = 4, 	CALLER_SP_OFFSET_BASE = 8,};  /* Current backtracer state describing where it thinks the caller is. */typedef struct {	/*	 * Public fields	 */ 	/* How do we find the caller's PC? */	CallerPCLocation pc_location : 8; 	/* How do we find the caller's SP? */	CallerSPLocation sp_location : 8; 	/* If sp_location == SP_LOC_OFFSET, then caller_sp == sp +	 * loc->sp_offset. Else this field is undefined.	 */	uint16_t sp_offset; 	/* In the most recently visited bundle a terminating bundle? */	bool at_terminating_bundle; 	/*	 * Private fields	 */ 	/* Will the forward scanner see someone clobbering sp	 * (i.e. changing it with something other than addi sp, sp, N?)	 */	bool sp_clobber_follows; 	/* Operand to next "visible" info op (no more than one bundle past	 * the next terminating bundle), or -32768 if none.	 */	int16_t next_info_operand; 	/* Is the info of in next_info_op in the very next bundle? */	bool is_next_info_operand_adjacent; } CallerLocation; extern void backtrace_init(BacktraceIterator *state,                          BacktraceMemoryReader read_memory_func,                          void *read_memory_func_extra,                          unsigned long pc, unsigned long lr,                          unsigned long sp, unsigned long r52);  extern bool backtrace_next(BacktraceIterator *state); #endif /* _ASM_TILE_BACKTRACE_H */