xref: /openbmc/qemu/target/arm/gdbstub64.c (revision 21c06f57)
1 /*
2  * ARM gdb server stub: AArch64 specific functions.
3  *
4  * Copyright (c) 2013 SUSE LINUX Products GmbH
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18  */
19 #include "qemu/osdep.h"
20 #include "qemu/log.h"
21 #include "cpu.h"
22 #include "internals.h"
23 #include "gdbstub/helpers.h"
24 
25 int aarch64_cpu_gdb_read_register(CPUState *cs, GByteArray *mem_buf, int n)
26 {
27     ARMCPU *cpu = ARM_CPU(cs);
28     CPUARMState *env = &cpu->env;
29 
30     if (n < 31) {
31         /* Core integer register.  */
32         return gdb_get_reg64(mem_buf, env->xregs[n]);
33     }
34     switch (n) {
35     case 31:
36         return gdb_get_reg64(mem_buf, env->xregs[31]);
37     case 32:
38         return gdb_get_reg64(mem_buf, env->pc);
39     case 33:
40         return gdb_get_reg32(mem_buf, pstate_read(env));
41     }
42     /* Unknown register.  */
43     return 0;
44 }
45 
46 int aarch64_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
47 {
48     ARMCPU *cpu = ARM_CPU(cs);
49     CPUARMState *env = &cpu->env;
50     uint64_t tmp;
51 
52     tmp = ldq_p(mem_buf);
53 
54     if (n < 31) {
55         /* Core integer register.  */
56         env->xregs[n] = tmp;
57         return 8;
58     }
59     switch (n) {
60     case 31:
61         env->xregs[31] = tmp;
62         return 8;
63     case 32:
64         env->pc = tmp;
65         return 8;
66     case 33:
67         /* CPSR */
68         pstate_write(env, tmp);
69         return 4;
70     }
71     /* Unknown register.  */
72     return 0;
73 }
74 
75 int aarch64_gdb_get_fpu_reg(CPUState *cs, GByteArray *buf, int reg)
76 {
77     ARMCPU *cpu = ARM_CPU(cs);
78     CPUARMState *env = &cpu->env;
79 
80     switch (reg) {
81     case 0 ... 31:
82     {
83         /* 128 bit FP register - quads are in LE order */
84         uint64_t *q = aa64_vfp_qreg(env, reg);
85         return gdb_get_reg128(buf, q[1], q[0]);
86     }
87     case 32:
88         /* FPSR */
89         return gdb_get_reg32(buf, vfp_get_fpsr(env));
90     case 33:
91         /* FPCR */
92         return gdb_get_reg32(buf, vfp_get_fpcr(env));
93     default:
94         return 0;
95     }
96 }
97 
98 int aarch64_gdb_set_fpu_reg(CPUState *cs, uint8_t *buf, int reg)
99 {
100     ARMCPU *cpu = ARM_CPU(cs);
101     CPUARMState *env = &cpu->env;
102 
103     switch (reg) {
104     case 0 ... 31:
105         /* 128 bit FP register */
106         {
107             uint64_t *q = aa64_vfp_qreg(env, reg);
108             q[0] = ldq_le_p(buf);
109             q[1] = ldq_le_p(buf + 8);
110             return 16;
111         }
112     case 32:
113         /* FPSR */
114         vfp_set_fpsr(env, ldl_p(buf));
115         return 4;
116     case 33:
117         /* FPCR */
118         vfp_set_fpcr(env, ldl_p(buf));
119         return 4;
120     default:
121         return 0;
122     }
123 }
124 
125 int aarch64_gdb_get_sve_reg(CPUState *cs, GByteArray *buf, int reg)
126 {
127     ARMCPU *cpu = ARM_CPU(cs);
128     CPUARMState *env = &cpu->env;
129 
130     switch (reg) {
131     /* The first 32 registers are the zregs */
132     case 0 ... 31:
133     {
134         int vq, len = 0;
135         for (vq = 0; vq < cpu->sve_max_vq; vq++) {
136             len += gdb_get_reg128(buf,
137                                   env->vfp.zregs[reg].d[vq * 2 + 1],
138                                   env->vfp.zregs[reg].d[vq * 2]);
139         }
140         return len;
141     }
142     case 32:
143         return gdb_get_reg32(buf, vfp_get_fpsr(env));
144     case 33:
145         return gdb_get_reg32(buf, vfp_get_fpcr(env));
146     /* then 16 predicates and the ffr */
147     case 34 ... 50:
148     {
149         int preg = reg - 34;
150         int vq, len = 0;
151         for (vq = 0; vq < cpu->sve_max_vq; vq = vq + 4) {
152             len += gdb_get_reg64(buf, env->vfp.pregs[preg].p[vq / 4]);
153         }
154         return len;
155     }
156     case 51:
157     {
158         /*
159          * We report in Vector Granules (VG) which is 64bit in a Z reg
160          * while the ZCR works in Vector Quads (VQ) which is 128bit chunks.
161          */
162         int vq = sve_vqm1_for_el(env, arm_current_el(env)) + 1;
163         return gdb_get_reg64(buf, vq * 2);
164     }
165     default:
166         /* gdbstub asked for something out our range */
167         qemu_log_mask(LOG_UNIMP, "%s: out of range register %d", __func__, reg);
168         break;
169     }
170 
171     return 0;
172 }
173 
174 int aarch64_gdb_set_sve_reg(CPUState *cs, uint8_t *buf, int reg)
175 {
176     ARMCPU *cpu = ARM_CPU(cs);
177     CPUARMState *env = &cpu->env;
178 
179     /* The first 32 registers are the zregs */
180     switch (reg) {
181     /* The first 32 registers are the zregs */
182     case 0 ... 31:
183     {
184         int vq, len = 0;
185         uint64_t *p = (uint64_t *) buf;
186         for (vq = 0; vq < cpu->sve_max_vq; vq++) {
187             env->vfp.zregs[reg].d[vq * 2 + 1] = *p++;
188             env->vfp.zregs[reg].d[vq * 2] = *p++;
189             len += 16;
190         }
191         return len;
192     }
193     case 32:
194         vfp_set_fpsr(env, *(uint32_t *)buf);
195         return 4;
196     case 33:
197         vfp_set_fpcr(env, *(uint32_t *)buf);
198         return 4;
199     case 34 ... 50:
200     {
201         int preg = reg - 34;
202         int vq, len = 0;
203         uint64_t *p = (uint64_t *) buf;
204         for (vq = 0; vq < cpu->sve_max_vq; vq = vq + 4) {
205             env->vfp.pregs[preg].p[vq / 4] = *p++;
206             len += 8;
207         }
208         return len;
209     }
210     case 51:
211         /* cannot set vg via gdbstub */
212         return 0;
213     default:
214         /* gdbstub asked for something out our range */
215         break;
216     }
217 
218     return 0;
219 }
220 
221 int aarch64_gdb_get_pauth_reg(CPUState *cs, GByteArray *buf, int reg)
222 {
223     ARMCPU *cpu = ARM_CPU(cs);
224     CPUARMState *env = &cpu->env;
225 
226     switch (reg) {
227     case 0: /* pauth_dmask */
228     case 1: /* pauth_cmask */
229     case 2: /* pauth_dmask_high */
230     case 3: /* pauth_cmask_high */
231         /*
232          * Note that older versions of this feature only contained
233          * pauth_{d,c}mask, for use with Linux user processes, and
234          * thus exclusively in the low half of the address space.
235          *
236          * To support system mode, and to debug kernels, two new regs
237          * were added to cover the high half of the address space.
238          * For the purpose of pauth_ptr_mask, we can use any well-formed
239          * address within the address space half -- here, 0 and -1.
240          */
241         {
242             bool is_data = !(reg & 1);
243             bool is_high = reg & 2;
244             ARMMMUIdx mmu_idx = arm_stage1_mmu_idx(env);
245             ARMVAParameters param;
246 
247             param = aa64_va_parameters(env, -is_high, mmu_idx, is_data, false);
248             return gdb_get_reg64(buf, pauth_ptr_mask(param));
249         }
250     default:
251         return 0;
252     }
253 }
254 
255 int aarch64_gdb_set_pauth_reg(CPUState *cs, uint8_t *buf, int reg)
256 {
257     /* All pseudo registers are read-only. */
258     return 0;
259 }
260 
261 static void output_vector_union_type(GDBFeatureBuilder *builder, int reg_width,
262                                      const char *name)
263 {
264     struct TypeSize {
265         const char *gdb_type;
266         short size;
267         char sz, suffix;
268     };
269 
270     static const struct TypeSize vec_lanes[] = {
271         /* quads */
272         { "uint128", 128, 'q', 'u' },
273         { "int128", 128, 'q', 's' },
274         /* 64 bit */
275         { "ieee_double", 64, 'd', 'f' },
276         { "uint64", 64, 'd', 'u' },
277         { "int64", 64, 'd', 's' },
278         /* 32 bit */
279         { "ieee_single", 32, 's', 'f' },
280         { "uint32", 32, 's', 'u' },
281         { "int32", 32, 's', 's' },
282         /* 16 bit */
283         { "ieee_half", 16, 'h', 'f' },
284         { "uint16", 16, 'h', 'u' },
285         { "int16", 16, 'h', 's' },
286         /* bytes */
287         { "uint8", 8, 'b', 'u' },
288         { "int8", 8, 'b', 's' },
289     };
290 
291     static const char suf[] = { 'b', 'h', 's', 'd', 'q' };
292     int i, j;
293 
294     /* First define types and totals in a whole VL */
295     for (i = 0; i < ARRAY_SIZE(vec_lanes); i++) {
296         gdb_feature_builder_append_tag(
297             builder, "<vector id=\"%s%c%c\" type=\"%s\" count=\"%d\"/>",
298             name, vec_lanes[i].sz, vec_lanes[i].suffix,
299             vec_lanes[i].gdb_type, reg_width / vec_lanes[i].size);
300     }
301 
302     /*
303      * Now define a union for each size group containing unsigned and
304      * signed and potentially float versions of each size from 128 to
305      * 8 bits.
306      */
307     for (i = 0; i < ARRAY_SIZE(suf); i++) {
308         int bits = 8 << i;
309 
310         gdb_feature_builder_append_tag(builder, "<union id=\"%sn%c\">",
311                                        name, suf[i]);
312         for (j = 0; j < ARRAY_SIZE(vec_lanes); j++) {
313             if (vec_lanes[j].size == bits) {
314                 gdb_feature_builder_append_tag(
315                     builder, "<field name=\"%c\" type=\"%s%c%c\"/>",
316                     vec_lanes[j].suffix, name,
317                     vec_lanes[j].sz, vec_lanes[j].suffix);
318             }
319         }
320         gdb_feature_builder_append_tag(builder, "</union>");
321     }
322 
323     /* And now the final union of unions */
324     gdb_feature_builder_append_tag(builder, "<union id=\"%s\">", name);
325     for (i = ARRAY_SIZE(suf) - 1; i >= 0; i--) {
326         gdb_feature_builder_append_tag(builder,
327                                        "<field name=\"%c\" type=\"%sn%c\"/>",
328                                        suf[i], name, suf[i]);
329     }
330     gdb_feature_builder_append_tag(builder, "</union>");
331 }
332 
333 GDBFeature *arm_gen_dynamic_svereg_feature(CPUState *cs, int base_reg)
334 {
335     ARMCPU *cpu = ARM_CPU(cs);
336     int reg_width = cpu->sve_max_vq * 128;
337     int pred_width = cpu->sve_max_vq * 16;
338     GDBFeatureBuilder builder;
339     char *name;
340     int reg = 0;
341     int i;
342 
343     gdb_feature_builder_init(&builder, &cpu->dyn_svereg_feature.desc,
344                              "org.gnu.gdb.aarch64.sve", "sve-registers.xml",
345                              base_reg);
346 
347     /* Create the vector union type. */
348     output_vector_union_type(&builder, reg_width, "svev");
349 
350     /* Create the predicate vector type. */
351     gdb_feature_builder_append_tag(
352         &builder, "<vector id=\"svep\" type=\"uint8\" count=\"%d\"/>",
353         pred_width / 8);
354 
355     /* Define the vector registers. */
356     for (i = 0; i < 32; i++) {
357         name = g_strdup_printf("z%d", i);
358         gdb_feature_builder_append_reg(&builder, name, reg_width, reg++,
359                                        "svev", NULL);
360     }
361 
362     /* fpscr & status registers */
363     gdb_feature_builder_append_reg(&builder, "fpsr", 32, reg++,
364                                    "int", "float");
365     gdb_feature_builder_append_reg(&builder, "fpcr", 32, reg++,
366                                    "int", "float");
367 
368     /* Define the predicate registers. */
369     for (i = 0; i < 16; i++) {
370         name = g_strdup_printf("p%d", i);
371         gdb_feature_builder_append_reg(&builder, name, pred_width, reg++,
372                                        "svep", NULL);
373     }
374     gdb_feature_builder_append_reg(&builder, "ffr", pred_width, reg++,
375                                    "svep", "vector");
376 
377     /* Define the vector length pseudo-register. */
378     gdb_feature_builder_append_reg(&builder, "vg", 64, reg++, "int", NULL);
379 
380     gdb_feature_builder_end(&builder);
381 
382     return &cpu->dyn_svereg_feature.desc;
383 }
384