xref: /qemu/target/loongarch/gdbstub.c (revision 6ff5da16000f908140723e164d33a0b51a6c4162)
1 /*
2  * LOONGARCH gdb server stub
3  *
4  * Copyright (c) 2021 Loongson Technology Corporation Limited
5  *
6  * SPDX-License-Identifier: LGPL-2.1+
7  */
8 
9 #include "qemu/osdep.h"
10 #include "cpu.h"
11 #include "internals.h"
12 #include "exec/gdbstub.h"
13 #include "gdbstub/helpers.h"
14 #include "vec.h"
15 
16 uint64_t read_fcc(CPULoongArchState *env)
17 {
18     uint64_t ret = 0;
19 
20     for (int i = 0; i < 8; ++i) {
21         ret |= (uint64_t)env->cf[i] << (i * 8);
22     }
23 
24     return ret;
25 }
26 
27 void write_fcc(CPULoongArchState *env, uint64_t val)
28 {
29     for (int i = 0; i < 8; ++i) {
30         env->cf[i] = (val >> (i * 8)) & 1;
31     }
32 }
33 
34 int loongarch_cpu_gdb_read_register(CPUState *cs, GByteArray *mem_buf, int n)
35 {
36     CPULoongArchState *env = cpu_env(cs);
37 
38     if (0 <= n && n <= 34) {
39         uint64_t val;
40 
41         if (n < 32) {
42             val = env->gpr[n];
43         } else if (n == 32) {
44             /* orig_a0 */
45             val = 0;
46         } else if (n == 33) {
47             val = env->pc;
48         } else /* if (n == 34) */ {
49             val = env->CSR_BADV;
50         }
51 
52         if (is_la64(env)) {
53             return gdb_get_reg64(mem_buf, val);
54         } else {
55             return gdb_get_reg32(mem_buf, val);
56         }
57     }
58 
59     return 0;
60 }
61 
62 int loongarch_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
63 {
64     CPULoongArchState *env = cpu_env(cs);
65     target_ulong tmp;
66     int length = 0;
67 
68     if (n < 0 || n > 34) {
69         return 0;
70     }
71 
72     if (is_la64(env)) {
73         tmp = ldq_le_p(mem_buf);
74         length = 8;
75     } else {
76         tmp = ldl_le_p(mem_buf);
77         length = 4;
78     }
79 
80     if (0 <= n && n < 32) {
81         env->gpr[n] = tmp;
82     } else if (n == 33) {
83         set_pc(env, tmp);
84     }
85     return length;
86 }
87 
88 static int loongarch_gdb_get_fpu(CPUState *cs, GByteArray *mem_buf, int n)
89 {
90     LoongArchCPU *cpu = LOONGARCH_CPU(cs);
91     CPULoongArchState *env = &cpu->env;
92 
93     if (0 <= n && n < 32) {
94         return gdb_get_reg64(mem_buf, env->fpr[n].vreg.D(0));
95     } else if (32 <= n && n < 40) {
96         return gdb_get_reg8(mem_buf, env->cf[n - 32]);
97     } else if (n == 40) {
98         return gdb_get_reg32(mem_buf, env->fcsr0);
99     }
100     return 0;
101 }
102 
103 static int loongarch_gdb_set_fpu(CPUState *cs, uint8_t *mem_buf, int n)
104 {
105     LoongArchCPU *cpu = LOONGARCH_CPU(cs);
106     CPULoongArchState *env = &cpu->env;
107     int length = 0;
108 
109     if (0 <= n && n < 32) {
110         env->fpr[n].vreg.D(0) = ldq_le_p(mem_buf);
111         length = 8;
112     } else if (32 <= n && n < 40) {
113         env->cf[n - 32] = ldub_p(mem_buf);
114         length = 1;
115     } else if (n == 40) {
116         env->fcsr0 = ldl_le_p(mem_buf);
117         length = 4;
118     }
119     return length;
120 }
121 
122 #define VREG_NUM       32
123 #define REG64_LEN      64
124 
125 static int loongarch_gdb_get_vec(CPUState *cs, GByteArray *mem_buf, int n, int vl)
126 {
127     LoongArchCPU *cpu = LOONGARCH_CPU(cs);
128     CPULoongArchState *env = &cpu->env;
129     int i, length = 0;
130 
131     if (0 <= n && n < VREG_NUM) {
132         for (i = 0; i < vl / REG64_LEN; i++) {
133             length += gdb_get_reg64(mem_buf, env->fpr[n].vreg.D(i));
134         }
135     }
136 
137     return length;
138 }
139 
140 static int loongarch_gdb_set_vec(CPUState *cs, uint8_t *mem_buf, int n, int vl)
141 {
142     LoongArchCPU *cpu = LOONGARCH_CPU(cs);
143     CPULoongArchState *env = &cpu->env;
144     int i, length = 0;
145 
146     if (0 <= n && n < VREG_NUM) {
147         for (i = 0; i < vl / REG64_LEN; i++) {
148             env->fpr[n].vreg.D(i) = ldq_le_p(mem_buf + 8 * i);
149             length += 8;
150         }
151     }
152 
153     return length;
154 }
155 
156 static int loongarch_gdb_get_lsx(CPUState *cs, GByteArray *mem_buf, int n)
157 {
158     return loongarch_gdb_get_vec(cs, mem_buf, n, LSX_LEN);
159 }
160 
161 static int loongarch_gdb_set_lsx(CPUState *cs, uint8_t *mem_buf, int n)
162 {
163     return loongarch_gdb_set_vec(cs, mem_buf, n, LSX_LEN);
164 }
165 
166 static int loongarch_gdb_get_lasx(CPUState *cs, GByteArray *mem_buf, int n)
167 {
168     return loongarch_gdb_get_vec(cs, mem_buf, n, LASX_LEN);
169 }
170 
171 static int loongarch_gdb_set_lasx(CPUState *cs, uint8_t *mem_buf, int n)
172 {
173     return loongarch_gdb_set_vec(cs, mem_buf, n, LASX_LEN);
174 }
175 
176 void loongarch_cpu_register_gdb_regs_for_features(CPUState *cs)
177 {
178     LoongArchCPU *cpu = LOONGARCH_CPU(cs);
179     CPULoongArchState *env = &cpu->env;
180 
181     if (FIELD_EX32(env->cpucfg[2], CPUCFG2, FP)) {
182         gdb_register_coprocessor(cs, loongarch_gdb_get_fpu, loongarch_gdb_set_fpu,
183                                  gdb_find_static_feature("loongarch-fpu.xml"), 0);
184     }
185 
186     if (FIELD_EX32(env->cpucfg[2], CPUCFG2, LSX)) {
187         gdb_register_coprocessor(cs, loongarch_gdb_get_lsx, loongarch_gdb_set_lsx,
188                                  gdb_find_static_feature("loongarch-lsx.xml"), 0);
189     }
190 
191     if (FIELD_EX32(env->cpucfg[2], CPUCFG2, LASX)) {
192         gdb_register_coprocessor(cs, loongarch_gdb_get_lasx, loongarch_gdb_set_lasx,
193                                  gdb_find_static_feature("loongarch-lasx.xml"), 0);
194     }
195 }
196