xref: /openbmc/qemu/target/hexagon/cpu.c (revision d5be19f5)
1 /*
2  *  Copyright(c) 2019-2023 Qualcomm Innovation Center, Inc. All Rights Reserved.
3  *
4  *  This program is free software; you can redistribute it and/or modify
5  *  it under the terms of the GNU General Public License as published by
6  *  the Free Software Foundation; either version 2 of the License, or
7  *  (at your option) any later version.
8  *
9  *  This program is distributed in the hope that it will be useful,
10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  *  GNU General Public License for more details.
13  *
14  *  You should have received a copy of the GNU General Public License
15  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
16  */
17 
18 #include "qemu/osdep.h"
19 #include "qemu/qemu-print.h"
20 #include "cpu.h"
21 #include "internal.h"
22 #include "exec/exec-all.h"
23 #include "qapi/error.h"
24 #include "hw/qdev-properties.h"
25 #include "fpu/softfloat-helpers.h"
26 #include "tcg/tcg.h"
27 #include "exec/gdbstub.h"
28 
29 static void hexagon_v67_cpu_init(Object *obj) { }
30 static void hexagon_v68_cpu_init(Object *obj) { }
31 static void hexagon_v69_cpu_init(Object *obj) { }
32 static void hexagon_v71_cpu_init(Object *obj) { }
33 static void hexagon_v73_cpu_init(Object *obj) { }
34 
35 static void hexagon_cpu_list_entry(gpointer data, gpointer user_data)
36 {
37     ObjectClass *oc = data;
38     char *name = g_strdup(object_class_get_name(oc));
39     if (g_str_has_suffix(name, HEXAGON_CPU_TYPE_SUFFIX)) {
40         name[strlen(name) - strlen(HEXAGON_CPU_TYPE_SUFFIX)] = '\0';
41     }
42     qemu_printf("  %s\n", name);
43     g_free(name);
44 }
45 
46 void hexagon_cpu_list(void)
47 {
48     GSList *list;
49     list = object_class_get_list_sorted(TYPE_HEXAGON_CPU, false);
50     qemu_printf("Available CPUs:\n");
51     g_slist_foreach(list, hexagon_cpu_list_entry, NULL);
52     g_slist_free(list);
53 }
54 
55 static ObjectClass *hexagon_cpu_class_by_name(const char *cpu_model)
56 {
57     ObjectClass *oc;
58     char *typename;
59     char **cpuname;
60 
61     cpuname = g_strsplit(cpu_model, ",", 1);
62     typename = g_strdup_printf(HEXAGON_CPU_TYPE_NAME("%s"), cpuname[0]);
63     oc = object_class_by_name(typename);
64     g_strfreev(cpuname);
65     g_free(typename);
66 
67     return oc;
68 }
69 
70 static Property hexagon_lldb_compat_property =
71     DEFINE_PROP_BOOL("lldb-compat", HexagonCPU, lldb_compat, false);
72 static Property hexagon_lldb_stack_adjust_property =
73     DEFINE_PROP_UNSIGNED("lldb-stack-adjust", HexagonCPU, lldb_stack_adjust,
74                          0, qdev_prop_uint32, target_ulong);
75 static Property hexagon_short_circuit_property =
76     DEFINE_PROP_BOOL("short-circuit", HexagonCPU, short_circuit, true);
77 
78 const char * const hexagon_regnames[TOTAL_PER_THREAD_REGS] = {
79    "r0", "r1",  "r2",  "r3",  "r4",   "r5",  "r6",  "r7",
80    "r8", "r9",  "r10", "r11", "r12",  "r13", "r14", "r15",
81   "r16", "r17", "r18", "r19", "r20",  "r21", "r22", "r23",
82   "r24", "r25", "r26", "r27", "r28",  "r29", "r30", "r31",
83   "sa0", "lc0", "sa1", "lc1", "p3_0", "c5",  "m0",  "m1",
84   "usr", "pc",  "ugp", "gp",  "cs0",  "cs1", "c14", "c15",
85   "c16", "c17", "c18", "c19", "pkt_cnt",  "insn_cnt", "hvx_cnt", "c23",
86   "c24", "c25", "c26", "c27", "c28",  "c29", "c30", "c31",
87 };
88 
89 /*
90  * One of the main debugging techniques is to use "-d cpu" and compare against
91  * LLDB output when single stepping.  However, the target and qemu put the
92  * stacks at different locations.  This is used to compensate so the diff is
93  * cleaner.
94  */
95 static target_ulong adjust_stack_ptrs(CPUHexagonState *env, target_ulong addr)
96 {
97     HexagonCPU *cpu = env_archcpu(env);
98     target_ulong stack_adjust = cpu->lldb_stack_adjust;
99     target_ulong stack_start = env->stack_start;
100     target_ulong stack_size = 0x10000;
101 
102     if (stack_adjust == 0) {
103         return addr;
104     }
105 
106     if (stack_start + 0x1000 >= addr && addr >= (stack_start - stack_size)) {
107         return addr - stack_adjust;
108     }
109     return addr;
110 }
111 
112 /* HEX_REG_P3_0_ALIASED (aka C4) is an alias for the predicate registers */
113 static target_ulong read_p3_0(CPUHexagonState *env)
114 {
115     int32_t control_reg = 0;
116     int i;
117     for (i = NUM_PREGS - 1; i >= 0; i--) {
118         control_reg <<= 8;
119         control_reg |= env->pred[i] & 0xff;
120     }
121     return control_reg;
122 }
123 
124 static void print_reg(FILE *f, CPUHexagonState *env, int regnum)
125 {
126     target_ulong value;
127 
128     if (regnum == HEX_REG_P3_0_ALIASED) {
129         value = read_p3_0(env);
130     } else {
131         value = regnum < 32 ? adjust_stack_ptrs(env, env->gpr[regnum])
132                             : env->gpr[regnum];
133     }
134 
135     qemu_fprintf(f, "  %s = 0x" TARGET_FMT_lx "\n",
136                  hexagon_regnames[regnum], value);
137 }
138 
139 static void print_vreg(FILE *f, CPUHexagonState *env, int regnum,
140                        bool skip_if_zero)
141 {
142     if (skip_if_zero) {
143         bool nonzero_found = false;
144         for (int i = 0; i < MAX_VEC_SIZE_BYTES; i++) {
145             if (env->VRegs[regnum].ub[i] != 0) {
146                 nonzero_found = true;
147                 break;
148             }
149         }
150         if (!nonzero_found) {
151             return;
152         }
153     }
154 
155     qemu_fprintf(f, "  v%d = ( ", regnum);
156     qemu_fprintf(f, "0x%02x", env->VRegs[regnum].ub[MAX_VEC_SIZE_BYTES - 1]);
157     for (int i = MAX_VEC_SIZE_BYTES - 2; i >= 0; i--) {
158         qemu_fprintf(f, ", 0x%02x", env->VRegs[regnum].ub[i]);
159     }
160     qemu_fprintf(f, " )\n");
161 }
162 
163 void hexagon_debug_vreg(CPUHexagonState *env, int regnum)
164 {
165     print_vreg(stdout, env, regnum, false);
166 }
167 
168 static void print_qreg(FILE *f, CPUHexagonState *env, int regnum,
169                        bool skip_if_zero)
170 {
171     if (skip_if_zero) {
172         bool nonzero_found = false;
173         for (int i = 0; i < MAX_VEC_SIZE_BYTES / 8; i++) {
174             if (env->QRegs[regnum].ub[i] != 0) {
175                 nonzero_found = true;
176                 break;
177             }
178         }
179         if (!nonzero_found) {
180             return;
181         }
182     }
183 
184     qemu_fprintf(f, "  q%d = ( ", regnum);
185     qemu_fprintf(f, "0x%02x",
186                  env->QRegs[regnum].ub[MAX_VEC_SIZE_BYTES / 8 - 1]);
187     for (int i = MAX_VEC_SIZE_BYTES / 8 - 2; i >= 0; i--) {
188         qemu_fprintf(f, ", 0x%02x", env->QRegs[regnum].ub[i]);
189     }
190     qemu_fprintf(f, " )\n");
191 }
192 
193 void hexagon_debug_qreg(CPUHexagonState *env, int regnum)
194 {
195     print_qreg(stdout, env, regnum, false);
196 }
197 
198 static void hexagon_dump(CPUHexagonState *env, FILE *f, int flags)
199 {
200     HexagonCPU *cpu = env_archcpu(env);
201 
202     if (cpu->lldb_compat) {
203         /*
204          * When comparing with LLDB, it doesn't step through single-cycle
205          * hardware loops the same way.  So, we just skip them here
206          */
207         if (env->gpr[HEX_REG_PC] == env->last_pc_dumped) {
208             return;
209         }
210         env->last_pc_dumped = env->gpr[HEX_REG_PC];
211     }
212 
213     qemu_fprintf(f, "General Purpose Registers = {\n");
214     for (int i = 0; i < 32; i++) {
215         print_reg(f, env, i);
216     }
217     print_reg(f, env, HEX_REG_SA0);
218     print_reg(f, env, HEX_REG_LC0);
219     print_reg(f, env, HEX_REG_SA1);
220     print_reg(f, env, HEX_REG_LC1);
221     print_reg(f, env, HEX_REG_M0);
222     print_reg(f, env, HEX_REG_M1);
223     print_reg(f, env, HEX_REG_USR);
224     print_reg(f, env, HEX_REG_P3_0_ALIASED);
225     print_reg(f, env, HEX_REG_GP);
226     print_reg(f, env, HEX_REG_UGP);
227     print_reg(f, env, HEX_REG_PC);
228 #ifdef CONFIG_USER_ONLY
229     /*
230      * Not modelled in user mode, print junk to minimize the diff's
231      * with LLDB output
232      */
233     qemu_fprintf(f, "  cause = 0x000000db\n");
234     qemu_fprintf(f, "  badva = 0x00000000\n");
235     qemu_fprintf(f, "  cs0 = 0x00000000\n");
236     qemu_fprintf(f, "  cs1 = 0x00000000\n");
237 #else
238     print_reg(f, env, HEX_REG_CAUSE);
239     print_reg(f, env, HEX_REG_BADVA);
240     print_reg(f, env, HEX_REG_CS0);
241     print_reg(f, env, HEX_REG_CS1);
242 #endif
243     qemu_fprintf(f, "}\n");
244 
245     if (flags & CPU_DUMP_FPU) {
246         qemu_fprintf(f, "Vector Registers = {\n");
247         for (int i = 0; i < NUM_VREGS; i++) {
248             print_vreg(f, env, i, true);
249         }
250         for (int i = 0; i < NUM_QREGS; i++) {
251             print_qreg(f, env, i, true);
252         }
253         qemu_fprintf(f, "}\n");
254     }
255 }
256 
257 static void hexagon_dump_state(CPUState *cs, FILE *f, int flags)
258 {
259     HexagonCPU *cpu = HEXAGON_CPU(cs);
260     CPUHexagonState *env = &cpu->env;
261 
262     hexagon_dump(env, f, flags);
263 }
264 
265 void hexagon_debug(CPUHexagonState *env)
266 {
267     hexagon_dump(env, stdout, CPU_DUMP_FPU);
268 }
269 
270 static void hexagon_cpu_set_pc(CPUState *cs, vaddr value)
271 {
272     HexagonCPU *cpu = HEXAGON_CPU(cs);
273     CPUHexagonState *env = &cpu->env;
274     env->gpr[HEX_REG_PC] = value;
275 }
276 
277 static vaddr hexagon_cpu_get_pc(CPUState *cs)
278 {
279     HexagonCPU *cpu = HEXAGON_CPU(cs);
280     CPUHexagonState *env = &cpu->env;
281     return env->gpr[HEX_REG_PC];
282 }
283 
284 static void hexagon_cpu_synchronize_from_tb(CPUState *cs,
285                                             const TranslationBlock *tb)
286 {
287     HexagonCPU *cpu = HEXAGON_CPU(cs);
288     CPUHexagonState *env = &cpu->env;
289     tcg_debug_assert(!(cs->tcg_cflags & CF_PCREL));
290     env->gpr[HEX_REG_PC] = tb->pc;
291 }
292 
293 static bool hexagon_cpu_has_work(CPUState *cs)
294 {
295     return true;
296 }
297 
298 static void hexagon_restore_state_to_opc(CPUState *cs,
299                                          const TranslationBlock *tb,
300                                          const uint64_t *data)
301 {
302     HexagonCPU *cpu = HEXAGON_CPU(cs);
303     CPUHexagonState *env = &cpu->env;
304 
305     env->gpr[HEX_REG_PC] = data[0];
306 }
307 
308 static void hexagon_cpu_reset_hold(Object *obj)
309 {
310     CPUState *cs = CPU(obj);
311     HexagonCPU *cpu = HEXAGON_CPU(cs);
312     HexagonCPUClass *mcc = HEXAGON_CPU_GET_CLASS(cpu);
313     CPUHexagonState *env = &cpu->env;
314 
315     if (mcc->parent_phases.hold) {
316         mcc->parent_phases.hold(obj);
317     }
318 
319     set_default_nan_mode(1, &env->fp_status);
320     set_float_detect_tininess(float_tininess_before_rounding, &env->fp_status);
321 }
322 
323 static void hexagon_cpu_disas_set_info(CPUState *s, disassemble_info *info)
324 {
325     info->print_insn = print_insn_hexagon;
326 }
327 
328 static void hexagon_cpu_realize(DeviceState *dev, Error **errp)
329 {
330     CPUState *cs = CPU(dev);
331     HexagonCPUClass *mcc = HEXAGON_CPU_GET_CLASS(dev);
332     Error *local_err = NULL;
333 
334     cpu_exec_realizefn(cs, &local_err);
335     if (local_err != NULL) {
336         error_propagate(errp, local_err);
337         return;
338     }
339 
340     gdb_register_coprocessor(cs, hexagon_hvx_gdb_read_register,
341                              hexagon_hvx_gdb_write_register,
342                              NUM_VREGS + NUM_QREGS,
343                              "hexagon-hvx.xml", 0);
344 
345     qemu_init_vcpu(cs);
346     cpu_reset(cs);
347 
348     mcc->parent_realize(dev, errp);
349 }
350 
351 static void hexagon_cpu_init(Object *obj)
352 {
353     qdev_property_add_static(DEVICE(obj), &hexagon_lldb_compat_property);
354     qdev_property_add_static(DEVICE(obj), &hexagon_lldb_stack_adjust_property);
355     qdev_property_add_static(DEVICE(obj), &hexagon_short_circuit_property);
356 }
357 
358 #include "hw/core/tcg-cpu-ops.h"
359 
360 static const struct TCGCPUOps hexagon_tcg_ops = {
361     .initialize = hexagon_translate_init,
362     .synchronize_from_tb = hexagon_cpu_synchronize_from_tb,
363     .restore_state_to_opc = hexagon_restore_state_to_opc,
364 };
365 
366 static void hexagon_cpu_class_init(ObjectClass *c, void *data)
367 {
368     HexagonCPUClass *mcc = HEXAGON_CPU_CLASS(c);
369     CPUClass *cc = CPU_CLASS(c);
370     DeviceClass *dc = DEVICE_CLASS(c);
371     ResettableClass *rc = RESETTABLE_CLASS(c);
372 
373     device_class_set_parent_realize(dc, hexagon_cpu_realize,
374                                     &mcc->parent_realize);
375 
376     resettable_class_set_parent_phases(rc, NULL, hexagon_cpu_reset_hold, NULL,
377                                        &mcc->parent_phases);
378 
379     cc->class_by_name = hexagon_cpu_class_by_name;
380     cc->has_work = hexagon_cpu_has_work;
381     cc->dump_state = hexagon_dump_state;
382     cc->set_pc = hexagon_cpu_set_pc;
383     cc->get_pc = hexagon_cpu_get_pc;
384     cc->gdb_read_register = hexagon_gdb_read_register;
385     cc->gdb_write_register = hexagon_gdb_write_register;
386     cc->gdb_num_core_regs = TOTAL_PER_THREAD_REGS;
387     cc->gdb_stop_before_watchpoint = true;
388     cc->gdb_core_xml_file = "hexagon-core.xml";
389     cc->disas_set_info = hexagon_cpu_disas_set_info;
390     cc->tcg_ops = &hexagon_tcg_ops;
391 }
392 
393 #define DEFINE_CPU(type_name, initfn)      \
394     {                                      \
395         .name = type_name,                 \
396         .parent = TYPE_HEXAGON_CPU,        \
397         .instance_init = initfn            \
398     }
399 
400 static const TypeInfo hexagon_cpu_type_infos[] = {
401     {
402         .name = TYPE_HEXAGON_CPU,
403         .parent = TYPE_CPU,
404         .instance_size = sizeof(HexagonCPU),
405         .instance_align = __alignof(HexagonCPU),
406         .instance_init = hexagon_cpu_init,
407         .abstract = true,
408         .class_size = sizeof(HexagonCPUClass),
409         .class_init = hexagon_cpu_class_init,
410     },
411     DEFINE_CPU(TYPE_HEXAGON_CPU_V67,              hexagon_v67_cpu_init),
412     DEFINE_CPU(TYPE_HEXAGON_CPU_V68,              hexagon_v68_cpu_init),
413     DEFINE_CPU(TYPE_HEXAGON_CPU_V69,              hexagon_v69_cpu_init),
414     DEFINE_CPU(TYPE_HEXAGON_CPU_V71,              hexagon_v71_cpu_init),
415     DEFINE_CPU(TYPE_HEXAGON_CPU_V73,              hexagon_v73_cpu_init),
416 };
417 
418 DEFINE_TYPES(hexagon_cpu_type_infos)
419