xref: /openbmc/qemu/target/openrisc/gdbstub.c (revision 750541c4)
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 "qemu-common.h"
22 #include "cpu.h"
23 #include "exec/gdbstub.h"
24 
25 int openrisc_cpu_gdb_read_register(CPUState *cs, uint8_t *mem_buf, int n)
26 {
27     OpenRISCCPU *cpu = OPENRISC_CPU(cs);
28     CPUOpenRISCState *env = &cpu->env;
29 
30     if (n < 32) {
31         return gdb_get_reg32(mem_buf, cpu_get_gpr(env, n));
32     } else {
33         switch (n) {
34         case 32:    /* PPC */
35             return gdb_get_reg32(mem_buf, env->ppc);
36 
37         case 33:    /* NPC (equals PC) */
38             return gdb_get_reg32(mem_buf, env->pc);
39 
40         case 34:    /* SR */
41             return gdb_get_reg32(mem_buf, cpu_get_sr(env));
42 
43         default:
44             break;
45         }
46     }
47     return 0;
48 }
49 
50 int openrisc_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
51 {
52     OpenRISCCPU *cpu = OPENRISC_CPU(cs);
53     CPUClass *cc = CPU_GET_CLASS(cs);
54     CPUOpenRISCState *env = &cpu->env;
55     uint32_t tmp;
56 
57     if (n > cc->gdb_num_core_regs) {
58         return 0;
59     }
60 
61     tmp = ldl_p(mem_buf);
62 
63     if (n < 32) {
64         cpu_set_gpr(env, n, tmp);
65     } else {
66         switch (n) {
67         case 32: /* PPC */
68             env->ppc = tmp;
69             break;
70 
71         case 33: /* NPC (equals PC) */
72             /* If setting PC to something different,
73                also clear delayed branch status.  */
74             if (env->pc != tmp) {
75                 env->pc = tmp;
76                 env->dflag = 0;
77             }
78             break;
79 
80         case 34: /* SR */
81             cpu_set_sr(env, tmp);
82             break;
83 
84         default:
85             break;
86         }
87     }
88     return 4;
89 }
90