xref: /openbmc/qemu/target/xtensa/gdbstub.c (revision ac06724a715864942e2b5e28f92d5d5421f0a0b0)
1 /*
2  * Xtensa 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 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 #include "qemu/log.h"
25 
26 int xtensa_cpu_gdb_read_register(CPUState *cs, uint8_t *mem_buf, int n)
27 {
28     XtensaCPU *cpu = XTENSA_CPU(cs);
29     CPUXtensaState *env = &cpu->env;
30     const XtensaGdbReg *reg = env->config->gdb_regmap.reg + n;
31     unsigned i;
32 
33     if (n < 0 || n >= env->config->gdb_regmap.num_regs) {
34         return 0;
35     }
36 
37     switch (reg->type) {
38     case 9: /*pc*/
39         return gdb_get_reg32(mem_buf, env->pc);
40 
41     case 1: /*ar*/
42         xtensa_sync_phys_from_window(env);
43         return gdb_get_reg32(mem_buf, env->phys_regs[(reg->targno & 0xff)
44                                                      % env->config->nareg]);
45 
46     case 2: /*SR*/
47         return gdb_get_reg32(mem_buf, env->sregs[reg->targno & 0xff]);
48 
49     case 3: /*UR*/
50         return gdb_get_reg32(mem_buf, env->uregs[reg->targno & 0xff]);
51 
52     case 4: /*f*/
53         i = reg->targno & 0x0f;
54         switch (reg->size) {
55         case 4:
56             return gdb_get_reg32(mem_buf,
57                                  float32_val(env->fregs[i].f32[FP_F32_LOW]));
58         case 8:
59             return gdb_get_reg64(mem_buf, float64_val(env->fregs[i].f64));
60         default:
61             qemu_log_mask(LOG_UNIMP, "%s from reg %d of unsupported size %d\n",
62                           __func__, n, reg->size);
63             memset(mem_buf, 0, reg->size);
64             return reg->size;
65         }
66 
67     case 8: /*a*/
68         return gdb_get_reg32(mem_buf, env->regs[reg->targno & 0x0f]);
69 
70     default:
71         qemu_log_mask(LOG_UNIMP, "%s from reg %d of unsupported type %d\n",
72                       __func__, n, reg->type);
73         memset(mem_buf, 0, reg->size);
74         return reg->size;
75         return 0;
76     }
77 }
78 
79 int xtensa_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
80 {
81     XtensaCPU *cpu = XTENSA_CPU(cs);
82     CPUXtensaState *env = &cpu->env;
83     uint32_t tmp;
84     const XtensaGdbReg *reg = env->config->gdb_regmap.reg + n;
85 
86     if (n < 0 || n >= env->config->gdb_regmap.num_regs) {
87         return 0;
88     }
89 
90     tmp = ldl_p(mem_buf);
91 
92     switch (reg->type) {
93     case 9: /*pc*/
94         env->pc = tmp;
95         break;
96 
97     case 1: /*ar*/
98         env->phys_regs[(reg->targno & 0xff) % env->config->nareg] = tmp;
99         xtensa_sync_window_from_phys(env);
100         break;
101 
102     case 2: /*SR*/
103         env->sregs[reg->targno & 0xff] = tmp;
104         break;
105 
106     case 3: /*UR*/
107         env->uregs[reg->targno & 0xff] = tmp;
108         break;
109 
110     case 4: /*f*/
111         switch (reg->size) {
112         case 4:
113             env->fregs[reg->targno & 0x0f].f32[FP_F32_LOW] = make_float32(tmp);
114             return 4;
115         case 8:
116             env->fregs[reg->targno & 0x0f].f64 = make_float64(tmp);
117             return 8;
118         default:
119             qemu_log_mask(LOG_UNIMP, "%s to reg %d of unsupported size %d\n",
120                           __func__, n, reg->size);
121             return reg->size;
122         }
123 
124     case 8: /*a*/
125         env->regs[reg->targno & 0x0f] = tmp;
126         break;
127 
128     default:
129         qemu_log_mask(LOG_UNIMP, "%s to reg %d of unsupported type %d\n",
130                       __func__, n, reg->type);
131         return reg->size;
132     }
133 
134     return 4;
135 }
136