text: /*
   * Copyright (C) 2001 - 2007 Tensilica Inc.
   *
   * SPDX-License-Identifier:	GPL-2.0+
   */
  
  #ifndef _XTENSA_PTRACE_H
  #define _XTENSA_PTRACE_H
  
  #include <compiler.h>
  
  /*
   * Kernel stack
   *
   *		+-----------------------+  -------- STACK_SIZE
   *		|     register file     |  |
   *		+-----------------------+  |
   *		|    struct pt_regs     |  |
   *		+-----------------------+  | ------ PT_REGS_OFFSET
   * double	:  16 bytes spill area  :  |  ^
   * exception	:- - - - - - - - - - - -:  |  |
   * frame	:    struct pt_regs     :  |  |
   *		:- - - - - - - - - - - -:  |  |
   *		|                       |  |  |
   *		|     memory stack      |  |  |
   *		|                       |  |  |
   *		~                       ~  ~  ~
   *		~                       ~  ~  ~
   *		|                       |  |  |
   *		|                       |  |  |
   *		+-----------------------+  |  | --- STACK_BIAS
   *		|  struct task_struct   |  |  |  ^
   *  current --> +-----------------------+  |  |  |
   *		|  struct thread_info   |  |  |  |
   *		+-----------------------+ --------
   */
  
  #define KERNEL_STACK_SIZE (2 * PAGE_SIZE)
  
  /*  Offsets for exception_handlers[] (3 x 64-entries x 4-byte tables) */
  
  #define EXC_TABLE_KSTK		0x004	/* Kernel Stack */
  #define EXC_TABLE_DOUBLE_SAVE	0x008	/* Double exception save area for a0 */
  #define EXC_TABLE_FIXUP		0x00c	/* Fixup handler */
  #define EXC_TABLE_PARAM		0x010	/* For passing a parameter to fixup */
  #define EXC_TABLE_SYSCALL_SAVE	0x014	/* For fast syscall handler */
  #define EXC_TABLE_FAST_USER	0x100	/* Fast user exception handler */
  #define EXC_TABLE_FAST_KERNEL	0x200	/* Fast kernel exception handler */
  #define EXC_TABLE_DEFAULT	0x300	/* Default C-Handler */
  #define EXC_TABLE_SIZE		0x400
  
  /* Registers used by strace */
  
  #define REG_A_BASE	0xfc000000
  #define REG_AR_BASE	0x04000000
  #define REG_PC		0x14000000
  #define REG_PS		0x080000e6
  #define REG_WB		0x08000048
  #define REG_WS		0x08000049
  #define REG_LBEG	0x08000000
  #define REG_LEND	0x08000001
  #define REG_LCOUNT	0x08000002
  #define REG_SAR		0x08000003
  #define REG_DEPC	0x080000c0
  #define REG_EXCCAUSE	0x080000e8
  #define REG_EXCVADDR	0x080000ee
  #define SYSCALL_NR	0x1
  
  #define AR_REGNO_TO_A_REGNO(ar, wb) (ar - wb*4) & ~(XCHAL_NUM_AREGS - 1)
  
  /* Other PTRACE_ values defined in <linux/ptrace.h> using values 0-9,16,17,24 */
  
  #define PTRACE_GETREGS            12
  #define PTRACE_SETREGS            13
  #define PTRACE_GETFPREGS          14
  #define PTRACE_SETFPREGS          15
  #define PTRACE_GETFPREGSIZE       18
  
  #ifndef __ASSEMBLY__
  
  /*
   * This struct defines the way the registers are stored on the
   * kernel stack during a system call or other kernel entry.
   */
  struct pt_regs {
  	unsigned long pc;		/*   4 */
  	unsigned long ps;		/*   8 */
  	unsigned long depc;		/*  12 */
  	unsigned long exccause;		/*  16 */
  	unsigned long excvaddr;		/*  20 */
  	unsigned long debugcause;	/*  24 */
  	unsigned long wmask;		/*  28 */
  	unsigned long lbeg;		/*  32 */
  	unsigned long lend;		/*  36 */
  	unsigned long lcount;		/*  40 */
  	unsigned long sar;		/*  44 */
  	unsigned long windowbase;	/*  48 */
  	unsigned long windowstart;	/*  52 */
  	unsigned long syscall;		/*  56 */
  	unsigned long icountlevel;	/*  60 */
  	int reserved[1];		/*  64 */
  
  	/* Make sure the areg field is 16 bytes aligned */
  	int align[0] __aligned(16);
  
  	/* current register frame.
  	 * Note: The ESF for kernel exceptions ends after 16 registers!
  	 */
  	unsigned long areg[16];		/* 128 (64) */
  };
  
  #ifdef __KERNEL__
  
  # define task_pt_regs(tsk) ((struct pt_regs *) \
  	(task_stack_page(tsk) + KERNEL_STACK_SIZE - (XCHAL_NUM_AREGS-16)*4) - 1)
  # define user_mode(regs) (((regs)->ps & 0x00000020) != 0)
  # define instruction_pointer(regs) ((regs)->pc)
  void show_regs(struct pt_regs *);
  
  # ifndef CONFIG_SMP
  #  define profile_pc(regs) instruction_pointer(regs)
  # endif
  #endif /* __KERNEL__ */
  
  #else	/* __ASSEMBLY__ */
  
  #ifdef __KERNEL__
  # include <asm/asm-offsets.h>
  #define PT_REGS_OFFSET	  (KERNEL_STACK_SIZE - PT_USER_SIZE)
  #endif
  
  #endif	/* !__ASSEMBLY__ */
  #endif	/* _XTENSA_PTRACE_H */
  