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