xref: /freebsd/sys/arm/arm/gdb_machdep.c (revision 0957b409)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2006 Olivier Houchard
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/kdb.h>
36 #include <sys/kernel.h>
37 #include <sys/proc.h>
38 #include <sys/signal.h>
39 
40 #include <machine/gdb_machdep.h>
41 #include <machine/db_machdep.h>
42 #include <machine/vmparam.h>
43 #include <machine/pcb.h>
44 #include <machine/trap.h>
45 #include <machine/frame.h>
46 #include <machine/endian.h>
47 
48 #include <gdb/gdb.h>
49 
50 static register_t stacktest;
51 
52 void *
53 gdb_cpu_getreg(int regnum, size_t *regsz)
54 {
55 
56 	*regsz = gdb_cpu_regsz(regnum);
57 
58 	if (kdb_thread == curthread) {
59 		if (regnum < 13)
60 			return (&kdb_frame->tf_r0 + regnum);
61 		if (regnum == 13)
62 			return (&kdb_frame->tf_svc_sp);
63 		if (regnum == 14)
64 			return (&kdb_frame->tf_svc_lr);
65 		if (regnum == 15)
66 			return (&kdb_frame->tf_pc);
67 		if (regnum == 25)
68 			return (&kdb_frame->tf_spsr);
69 	}
70 
71 	switch (regnum) {
72 	case 4:  return (&kdb_thrctx->pcb_regs.sf_r4);
73 	case 5:  return (&kdb_thrctx->pcb_regs.sf_r5);
74 	case 6:  return (&kdb_thrctx->pcb_regs.sf_r6);
75 	case 7:  return (&kdb_thrctx->pcb_regs.sf_r7);
76 	case 8:  return (&kdb_thrctx->pcb_regs.sf_r8);
77 	case 9:  return (&kdb_thrctx->pcb_regs.sf_r9);
78 	case 10:  return (&kdb_thrctx->pcb_regs.sf_r10);
79 	case 11:  return (&kdb_thrctx->pcb_regs.sf_r11);
80 	case 12:  return (&kdb_thrctx->pcb_regs.sf_r12);
81 	case 13:  stacktest = kdb_thrctx->pcb_regs.sf_sp + 5 * 4;
82 		  return (&stacktest);
83 	case 15:
84 		  /*
85 		   * On context switch, the PC is not put in the PCB, but
86 		   * we can retrieve it from the stack.
87 		   */
88 		  if (kdb_thrctx->pcb_regs.sf_sp > KERNBASE) {
89 			  kdb_thrctx->pcb_regs.sf_pc = *(register_t *)
90 			      (kdb_thrctx->pcb_regs.sf_sp + 4 * 4);
91 			  return (&kdb_thrctx->pcb_regs.sf_pc);
92 		  }
93 	}
94 
95 	return (NULL);
96 }
97 
98 void
99 gdb_cpu_setreg(int regnum, void *val)
100 {
101 
102 	switch (regnum) {
103 	case GDB_REG_PC:
104 		if (kdb_thread  == curthread)
105 			kdb_frame->tf_pc = *(register_t *)val;
106 	}
107 }
108 
109 int
110 gdb_cpu_signal(int type, int code)
111 {
112 
113 	switch (type) {
114 	case T_BREAKPOINT: return (SIGTRAP);
115 	}
116 	return (SIGEMT);
117 }
118