xref: /openbmc/qemu/target/openrisc/gdbstub.c (revision d044b7c3)
1 /*
2  * OpenRISC gdb server stub
3  *
4  * Copyright (c) 2003-2005 Fabrice Bellard
5  * Copyright (c) 2013 SUSE LINUX Products GmbH
6  *
7  * This library is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * This library is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
19  */
20 #include "qemu/osdep.h"
21 #include "cpu.h"
22 #include "gdbstub/helpers.h"
23 
24 int openrisc_cpu_gdb_read_register(CPUState *cs, GByteArray *mem_buf, int n)
25 {
26     OpenRISCCPU *cpu = OPENRISC_CPU(cs);
27     CPUOpenRISCState *env = &cpu->env;
28 
29     if (n < 32) {
30         return gdb_get_reg32(mem_buf, cpu_get_gpr(env, n));
31     } else {
32         switch (n) {
33         case 32:    /* PPC */
34             return gdb_get_reg32(mem_buf, env->ppc);
35 
36         case 33:    /* NPC (equals PC) */
37             return gdb_get_reg32(mem_buf, env->pc);
38 
39         case 34:    /* SR */
40             return gdb_get_reg32(mem_buf, cpu_get_sr(env));
41 
42         default:
43             break;
44         }
45     }
46     return 0;
47 }
48 
49 int openrisc_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
50 {
51     OpenRISCCPU *cpu = OPENRISC_CPU(cs);
52     CPUClass *cc = CPU_GET_CLASS(cs);
53     CPUOpenRISCState *env = &cpu->env;
54     uint32_t tmp;
55 
56     if (n > cc->gdb_num_core_regs) {
57         return 0;
58     }
59 
60     tmp = ldl_p(mem_buf);
61 
62     if (n < 32) {
63         cpu_set_gpr(env, n, tmp);
64     } else {
65         switch (n) {
66         case 32: /* PPC */
67             env->ppc = tmp;
68             break;
69 
70         case 33: /* NPC (equals PC) */
71             /* If setting PC to something different,
72                also clear delayed branch status.  */
73             if (env->pc != tmp) {
74                 env->pc = tmp;
75                 env->dflag = 0;
76             }
77             break;
78 
79         case 34: /* SR */
80             cpu_set_sr(env, tmp);
81             break;
82 
83         default:
84             break;
85         }
86     }
87     return 4;
88 }
89