1  /* SPDX-License-Identifier: GPL-2.0 */
2  /*
3   * kdebug.h:  Defines and definitions for debugging the Linux kernel
4   *            under various kernel debuggers.
5   *
6   * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
7   */
8  #ifndef _SPARC_KDEBUG_H
9  #define _SPARC_KDEBUG_H
10  
11  #include <asm/openprom.h>
12  #include <asm/vaddrs.h>
13  
14  /* Breakpoints are enter through trap table entry 126.  So in sparc assembly
15   * if you want to drop into the debugger you do:
16   *
17   * t DEBUG_BP_TRAP
18   */
19  
20  #define DEBUG_BP_TRAP     126
21  
22  #ifndef __ASSEMBLY__
23  /* The debug vector is passed in %o1 at boot time.  It is a pointer to
24   * a structure in the debuggers address space.  Here is its format.
25   */
26  
27  typedef unsigned int (*debugger_funct)(void);
28  
29  struct kernel_debug {
30  	/* First the entry point into the debugger.  You jump here
31  	 * to give control over to the debugger.
32  	 */
33  	unsigned long kdebug_entry;
34  	unsigned long kdebug_trapme;   /* Figure out later... */
35  	/* The following is the number of pages that the debugger has
36  	 * taken from to total pool.
37  	 */
38  	unsigned long *kdebug_stolen_pages;
39  	/* Ok, after you remap yourself and/or change the trap table
40  	 * from what you were left with at boot time you have to call
41  	 * this synchronization function so the debugger can check out
42  	 * what you have done.
43  	 */
44  	debugger_funct teach_debugger;
45  }; /* I think that is it... */
46  
47  extern struct kernel_debug *linux_dbvec;
48  
49  /* Use this macro in C-code to enter the debugger. */
sp_enter_debugger(void)50  static inline void sp_enter_debugger(void)
51  {
52  	__asm__ __volatile__("jmpl %0, %%o7\n\t"
53  			     "nop\n\t" : :
54  			     "r" (linux_dbvec) : "o7", "memory");
55  }
56  
57  #define SP_ENTER_DEBUGGER do { \
58  	     if((linux_dbvec!=0) && ((*(short *)linux_dbvec)!=-1)) \
59  	       sp_enter_debugger(); \
60  		       } while(0)
61  
62  enum die_val {
63  	DIE_UNUSED,
64  	DIE_OOPS,
65  };
66  
67  #endif /* !(__ASSEMBLY__) */
68  
69  /* Some nice offset defines for assembler code. */
70  #define KDEBUG_ENTRY_OFF    0x0
71  #define KDEBUG_DUNNO_OFF    0x4
72  #define KDEBUG_DUNNO2_OFF   0x8
73  #define KDEBUG_TEACH_OFF    0xc
74  
75  #endif /* !(_SPARC_KDEBUG_H) */
76