1/*
2 * RISC-V GDB Server Stub
3 *
4 * Copyright (c) 2016-2017 Sagar Karandikar, sagark@eecs.berkeley.edu
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2 or later, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License along with
16 * this program. If not, see <http://www.gnu.org/licenses/>.
17 */
18
19#include "qemu/osdep.h"
20#include "exec/gdbstub.h"
21#include "cpu.h"
22
23/*
24 * The GDB CSR xml files list them in documentation order, not numerical order,
25 * and are missing entries for unnamed CSRs. So we need to map the gdb numbers
26 * to the hardware numbers.
27 */
28
29static int csr_register_map[] = {
30 CSR_USTATUS,
31 CSR_UIE,
32 CSR_UTVEC,
33 CSR_USCRATCH,
34 CSR_UEPC,
35 CSR_UCAUSE,
36 CSR_UTVAL,
37 CSR_UIP,
38 CSR_FFLAGS,
39 CSR_FRM,
40 CSR_FCSR,
41 CSR_CYCLE,
42 CSR_TIME,
43 CSR_INSTRET,
44 CSR_HPMCOUNTER3,
45 CSR_HPMCOUNTER4,
46 CSR_HPMCOUNTER5,
47 CSR_HPMCOUNTER6,
48 CSR_HPMCOUNTER7,
49 CSR_HPMCOUNTER8,
50 CSR_HPMCOUNTER9,
51 CSR_HPMCOUNTER10,
52 CSR_HPMCOUNTER11,
53 CSR_HPMCOUNTER12,
54 CSR_HPMCOUNTER13,
55 CSR_HPMCOUNTER14,
56 CSR_HPMCOUNTER15,
57 CSR_HPMCOUNTER16,
58 CSR_HPMCOUNTER17,
59 CSR_HPMCOUNTER18,
60 CSR_HPMCOUNTER19,
61 CSR_HPMCOUNTER20,
62 CSR_HPMCOUNTER21,
63 CSR_HPMCOUNTER22,
64 CSR_HPMCOUNTER23,
65 CSR_HPMCOUNTER24,
66 CSR_HPMCOUNTER25,
67 CSR_HPMCOUNTER26,
68 CSR_HPMCOUNTER27,
69 CSR_HPMCOUNTER28,
70 CSR_HPMCOUNTER29,
71 CSR_HPMCOUNTER30,
72 CSR_HPMCOUNTER31,
73 CSR_CYCLEH,
74 CSR_TIMEH,
75 CSR_INSTRETH,
76 CSR_HPMCOUNTER3H,
77 CSR_HPMCOUNTER4H,
78 CSR_HPMCOUNTER5H,
79 CSR_HPMCOUNTER6H,
80 CSR_HPMCOUNTER7H,
81 CSR_HPMCOUNTER8H,
82 CSR_HPMCOUNTER9H,
83 CSR_HPMCOUNTER10H,
84 CSR_HPMCOUNTER11H,
85 CSR_HPMCOUNTER12H,
86 CSR_HPMCOUNTER13H,
87 CSR_HPMCOUNTER14H,
88 CSR_HPMCOUNTER15H,
89 CSR_HPMCOUNTER16H,
90 CSR_HPMCOUNTER17H,
91 CSR_HPMCOUNTER18H,
92 CSR_HPMCOUNTER19H,
93 CSR_HPMCOUNTER20H,
94 CSR_HPMCOUNTER21H,
95 CSR_HPMCOUNTER22H,
96 CSR_HPMCOUNTER23H,
97 CSR_HPMCOUNTER24H,
98 CSR_HPMCOUNTER25H,
99 CSR_HPMCOUNTER26H,
100 CSR_HPMCOUNTER27H,
101 CSR_HPMCOUNTER28H,
102 CSR_HPMCOUNTER29H,
103 CSR_HPMCOUNTER30H,
104 CSR_HPMCOUNTER31H,
105 CSR_SSTATUS,
106 CSR_SEDELEG,
107 CSR_SIDELEG,
108 CSR_SIE,
109 CSR_STVEC,
110 CSR_SCOUNTEREN,
111 CSR_SSCRATCH,
112 CSR_SEPC,
113 CSR_SCAUSE,
114 CSR_STVAL,
115 CSR_SIP,
116 CSR_SATP,
117 CSR_MVENDORID,
118 CSR_MARCHID,
119 CSR_MIMPID,
120 CSR_MHARTID,
121 CSR_MSTATUS,
122 CSR_MISA,
123 CSR_MEDELEG,
124 CSR_MIDELEG,
125 CSR_MIE,
126 CSR_MTVEC,
127 CSR_MCOUNTEREN,
128 CSR_MSCRATCH,
129 CSR_MEPC,
130 CSR_MCAUSE,
131 CSR_MTVAL,
132 CSR_MIP,
133 CSR_PMPCFG0,
134 CSR_PMPCFG1,
135 CSR_PMPCFG2,
136 CSR_PMPCFG3,
137 CSR_PMPADDR0,
138 CSR_PMPADDR1,
139 CSR_PMPADDR2,
140 CSR_PMPADDR3,
141 CSR_PMPADDR4,
142 CSR_PMPADDR5,
143 CSR_PMPADDR6,
144 CSR_PMPADDR7,
145 CSR_PMPADDR8,
146 CSR_PMPADDR9,
147 CSR_PMPADDR10,
148 CSR_PMPADDR11,
149 CSR_PMPADDR12,
150 CSR_PMPADDR13,
151 CSR_PMPADDR14,
152 CSR_PMPADDR15,
153 CSR_MCYCLE,
154 CSR_MINSTRET,
155 CSR_MHPMCOUNTER3,
156 CSR_MHPMCOUNTER4,
157 CSR_MHPMCOUNTER5,
158 CSR_MHPMCOUNTER6,
159 CSR_MHPMCOUNTER7,
160 CSR_MHPMCOUNTER8,
161 CSR_MHPMCOUNTER9,
162 CSR_MHPMCOUNTER10,
163 CSR_MHPMCOUNTER11,
164 CSR_MHPMCOUNTER12,
165 CSR_MHPMCOUNTER13,
166 CSR_MHPMCOUNTER14,
167 CSR_MHPMCOUNTER15,
168 CSR_MHPMCOUNTER16,
169 CSR_MHPMCOUNTER17,
170 CSR_MHPMCOUNTER18,
171 CSR_MHPMCOUNTER19,
172 CSR_MHPMCOUNTER20,
173 CSR_MHPMCOUNTER21,
174 CSR_MHPMCOUNTER22,
175 CSR_MHPMCOUNTER23,
176 CSR_MHPMCOUNTER24,
177 CSR_MHPMCOUNTER25,
178 CSR_MHPMCOUNTER26,
179 CSR_MHPMCOUNTER27,
180 CSR_MHPMCOUNTER28,
181 CSR_MHPMCOUNTER29,
182 CSR_MHPMCOUNTER30,
183 CSR_MHPMCOUNTER31,
184 CSR_MCYCLEH,
185 CSR_MINSTRETH,
186 CSR_MHPMCOUNTER3H,
187 CSR_MHPMCOUNTER4H,
188 CSR_MHPMCOUNTER5H,
189 CSR_MHPMCOUNTER6H,
190 CSR_MHPMCOUNTER7H,
191 CSR_MHPMCOUNTER8H,
192 CSR_MHPMCOUNTER9H,
193 CSR_MHPMCOUNTER10H,
194 CSR_MHPMCOUNTER11H,
195 CSR_MHPMCOUNTER12H,
196 CSR_MHPMCOUNTER13H,
197 CSR_MHPMCOUNTER14H,
198 CSR_MHPMCOUNTER15H,
199 CSR_MHPMCOUNTER16H,
200 CSR_MHPMCOUNTER17H,
201 CSR_MHPMCOUNTER18H,
202 CSR_MHPMCOUNTER19H,
203 CSR_MHPMCOUNTER20H,
204 CSR_MHPMCOUNTER21H,
205 CSR_MHPMCOUNTER22H,
206 CSR_MHPMCOUNTER23H,
207 CSR_MHPMCOUNTER24H,
208 CSR_MHPMCOUNTER25H,
209 CSR_MHPMCOUNTER26H,
210 CSR_MHPMCOUNTER27H,
211 CSR_MHPMCOUNTER28H,
212 CSR_MHPMCOUNTER29H,
213 CSR_MHPMCOUNTER30H,
214 CSR_MHPMCOUNTER31H,
215 CSR_MHPMEVENT3,
216 CSR_MHPMEVENT4,
217 CSR_MHPMEVENT5,
218 CSR_MHPMEVENT6,
219 CSR_MHPMEVENT7,
220 CSR_MHPMEVENT8,
221 CSR_MHPMEVENT9,
222 CSR_MHPMEVENT10,
223 CSR_MHPMEVENT11,
224 CSR_MHPMEVENT12,
225 CSR_MHPMEVENT13,
226 CSR_MHPMEVENT14,
227 CSR_MHPMEVENT15,
228 CSR_MHPMEVENT16,
229 CSR_MHPMEVENT17,
230 CSR_MHPMEVENT18,
231 CSR_MHPMEVENT19,
232 CSR_MHPMEVENT20,
233 CSR_MHPMEVENT21,
234 CSR_MHPMEVENT22,
235 CSR_MHPMEVENT23,
236 CSR_MHPMEVENT24,
237 CSR_MHPMEVENT25,
238 CSR_MHPMEVENT26,
239 CSR_MHPMEVENT27,
240 CSR_MHPMEVENT28,
241 CSR_MHPMEVENT29,
242 CSR_MHPMEVENT30,
243 CSR_MHPMEVENT31,
244 CSR_TSELECT,
245 CSR_TDATA1,
246 CSR_TDATA2,
247 CSR_TDATA3,
248 CSR_DCSR,
249 CSR_DPC,
250 CSR_DSCRATCH,
251 CSR_HSTATUS,
252 CSR_HEDELEG,
253 CSR_HIDELEG,
254 CSR_HIE,
255 CSR_HTVEC,
256 CSR_HSCRATCH,
257 CSR_HEPC,
258 CSR_HCAUSE,
259 CSR_HBADADDR,
260 CSR_HIP,
261 CSR_MBASE,
262 CSR_MBOUND,
263 CSR_MIBASE,
264 CSR_MIBOUND,
265 CSR_MDBASE,
266 CSR_MDBOUND,
267 CSR_MUCOUNTEREN,
268 CSR_MSCOUNTEREN,
269 CSR_MHCOUNTEREN,
270};
271
272int riscv_cpu_gdb_read_register(CPUState *cs, uint8_t *mem_buf, int n)
273{
274 RISCVCPU *cpu = RISCV_CPU(cs);
275 CPURISCVState *env = &cpu->env;
276
277 if (n < 32) {
278 return gdb_get_regl(mem_buf, env->gpr[n]);
279 } else if (n == 32) {
280 return gdb_get_regl(mem_buf, env->pc);
281 }
282 return 0;
283}
284
285int riscv_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
286{
287 RISCVCPU *cpu = RISCV_CPU(cs);
288 CPURISCVState *env = &cpu->env;
289
290 if (n == 0) {
291 /* discard writes to x0 */
292 return sizeof(target_ulong);
293 } else if (n < 32) {
294 env->gpr[n] = ldtul_p(mem_buf);
295 return sizeof(target_ulong);
296 } else if (n == 32) {
297 env->pc = ldtul_p(mem_buf);
298 return sizeof(target_ulong);
299 }
300 return 0;
301}
302
303static int riscv_gdb_get_fpu(CPURISCVState *env, uint8_t *mem_buf, int n)
304{
305 if (n < 32) {
306 return gdb_get_reg64(mem_buf, env->fpr[n]);
307 /* there is hole between ft11 and fflags in fpu.xml */
308 } else if (n < 36 && n > 32) {
309 target_ulong val = 0;
310 int result;
311 /*
312 * CSR_FFLAGS is at index 8 in csr_register, and gdb says it is FP
313 * register 33, so we recalculate the map index.
314 * This also works for CSR_FRM and CSR_FCSR.
315 */
316 result = riscv_csrrw_debug(env, n - 33 + 8, &val, 0, 0);
317 if (result == 0) {
318 return gdb_get_regl(mem_buf, val);
319 }
320 }
321 return 0;
322}
323
324static int riscv_gdb_set_fpu(CPURISCVState *env, uint8_t *mem_buf, int n)
325{
326 if (n < 32) {
327 env->fpr[n] = ldq_p(mem_buf); /* always 64-bit */
328 return sizeof(uint64_t);
329 /* there is hole between ft11 and fflags in fpu.xml */
330 } else if (n < 36 && n > 32) {
331 target_ulong val = ldtul_p(mem_buf);
332 int result;
333 /*
334 * CSR_FFLAGS is at index 8 in csr_register, and gdb says it is FP
335 * register 33, so we recalculate the map index.
336 * This also works for CSR_FRM and CSR_FCSR.
337 */
338 result = riscv_csrrw_debug(env, n - 33 + 8, NULL, val, -1);
339 if (result == 0) {
340 return sizeof(target_ulong);
341 }
342 }
343 return 0;
344}
345
346static int riscv_gdb_get_csr(CPURISCVState *env, uint8_t *mem_buf, int n)
347{
348 if (n < ARRAY_SIZE(csr_register_map)) {
349 target_ulong val = 0;
350 int result;
351
352 result = riscv_csrrw_debug(env, csr_register_map[n], &val, 0, 0);
353 if (result == 0) {
354 return gdb_get_regl(mem_buf, val);
355 }
356 }
357 return 0;
358}
359
360static int riscv_gdb_set_csr(CPURISCVState *env, uint8_t *mem_buf, int n)
361{
362 if (n < ARRAY_SIZE(csr_register_map)) {
363 target_ulong val = ldtul_p(mem_buf);
364 int result;
365
366 result = riscv_csrrw_debug(env, csr_register_map[n], NULL, val, -1);
367 if (result == 0) {
368 return sizeof(target_ulong);
369 }
370 }
371 return 0;
372}
373
374void riscv_cpu_register_gdb_regs_for_features(CPUState *cs)
375{
376 RISCVCPU *cpu = RISCV_CPU(cs);
377 CPURISCVState *env = &cpu->env;
378#if defined(TARGET_RISCV32)
379 if (env->misa & RVF) {
380 gdb_register_coprocessor(cs, riscv_gdb_get_fpu, riscv_gdb_set_fpu,
381 36, "riscv-32bit-fpu.xml", 0);
382 }
383
384 gdb_register_coprocessor(cs, riscv_gdb_get_csr, riscv_gdb_set_csr,
385 4096, "riscv-32bit-csr.xml", 0);
386#elif defined(TARGET_RISCV64)
387 if (env->misa & RVF) {
388 gdb_register_coprocessor(cs, riscv_gdb_get_fpu, riscv_gdb_set_fpu,
389 36, "riscv-64bit-fpu.xml", 0);
390 }
391
392 gdb_register_coprocessor(cs, riscv_gdb_get_csr, riscv_gdb_set_csr,
393 4096, "riscv-64bit-csr.xml", 0);
394#endif
395}
396