xref: /openbmc/qemu/target/hexagon/cpu.c (revision 259ebed4)
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     if (!oc || !object_class_dynamic_cast(oc, TYPE_HEXAGON_CPU) ||
67         object_class_is_abstract(oc)) {
68         return NULL;
69     }
70     return oc;
71 }
72 
73 static Property hexagon_lldb_compat_property =
74     DEFINE_PROP_BOOL("lldb-compat", HexagonCPU, lldb_compat, false);
75 static Property hexagon_lldb_stack_adjust_property =
76     DEFINE_PROP_UNSIGNED("lldb-stack-adjust", HexagonCPU, lldb_stack_adjust,
77                          0, qdev_prop_uint32, target_ulong);
78 static Property hexagon_short_circuit_property =
79     DEFINE_PROP_BOOL("short-circuit", HexagonCPU, short_circuit, true);
80 
81 const char * const hexagon_regnames[TOTAL_PER_THREAD_REGS] = {
82    "r0", "r1",  "r2",  "r3",  "r4",   "r5",  "r6",  "r7",
83    "r8", "r9",  "r10", "r11", "r12",  "r13", "r14", "r15",
84   "r16", "r17", "r18", "r19", "r20",  "r21", "r22", "r23",
85   "r24", "r25", "r26", "r27", "r28",  "r29", "r30", "r31",
86   "sa0", "lc0", "sa1", "lc1", "p3_0", "c5",  "m0",  "m1",
87   "usr", "pc",  "ugp", "gp",  "cs0",  "cs1", "c14", "c15",
88   "c16", "c17", "c18", "c19", "pkt_cnt",  "insn_cnt", "hvx_cnt", "c23",
89   "c24", "c25", "c26", "c27", "c28",  "c29", "c30", "c31",
90 };
91 
92 /*
93  * One of the main debugging techniques is to use "-d cpu" and compare against
94  * LLDB output when single stepping.  However, the target and qemu put the
95  * stacks at different locations.  This is used to compensate so the diff is
96  * cleaner.
97  */
98 static target_ulong adjust_stack_ptrs(CPUHexagonState *env, target_ulong addr)
99 {
100     HexagonCPU *cpu = env_archcpu(env);
101     target_ulong stack_adjust = cpu->lldb_stack_adjust;
102     target_ulong stack_start = env->stack_start;
103     target_ulong stack_size = 0x10000;
104 
105     if (stack_adjust == 0) {
106         return addr;
107     }
108 
109     if (stack_start + 0x1000 >= addr && addr >= (stack_start - stack_size)) {
110         return addr - stack_adjust;
111     }
112     return addr;
113 }
114 
115 /* HEX_REG_P3_0_ALIASED (aka C4) is an alias for the predicate registers */
116 static target_ulong read_p3_0(CPUHexagonState *env)
117 {
118     int32_t control_reg = 0;
119     int i;
120     for (i = NUM_PREGS - 1; i >= 0; i--) {
121         control_reg <<= 8;
122         control_reg |= env->pred[i] & 0xff;
123     }
124     return control_reg;
125 }
126 
127 static void print_reg(FILE *f, CPUHexagonState *env, int regnum)
128 {
129     target_ulong value;
130 
131     if (regnum == HEX_REG_P3_0_ALIASED) {
132         value = read_p3_0(env);
133     } else {
134         value = regnum < 32 ? adjust_stack_ptrs(env, env->gpr[regnum])
135                             : env->gpr[regnum];
136     }
137 
138     qemu_fprintf(f, "  %s = 0x" TARGET_FMT_lx "\n",
139                  hexagon_regnames[regnum], value);
140 }
141 
142 static void print_vreg(FILE *f, CPUHexagonState *env, int regnum,
143                        bool skip_if_zero)
144 {
145     if (skip_if_zero) {
146         bool nonzero_found = false;
147         for (int i = 0; i < MAX_VEC_SIZE_BYTES; i++) {
148             if (env->VRegs[regnum].ub[i] != 0) {
149                 nonzero_found = true;
150                 break;
151             }
152         }
153         if (!nonzero_found) {
154             return;
155         }
156     }
157 
158     qemu_fprintf(f, "  v%d = ( ", regnum);
159     qemu_fprintf(f, "0x%02x", env->VRegs[regnum].ub[MAX_VEC_SIZE_BYTES - 1]);
160     for (int i = MAX_VEC_SIZE_BYTES - 2; i >= 0; i--) {
161         qemu_fprintf(f, ", 0x%02x", env->VRegs[regnum].ub[i]);
162     }
163     qemu_fprintf(f, " )\n");
164 }
165 
166 void hexagon_debug_vreg(CPUHexagonState *env, int regnum)
167 {
168     print_vreg(stdout, env, regnum, false);
169 }
170 
171 static void print_qreg(FILE *f, CPUHexagonState *env, int regnum,
172                        bool skip_if_zero)
173 {
174     if (skip_if_zero) {
175         bool nonzero_found = false;
176         for (int i = 0; i < MAX_VEC_SIZE_BYTES / 8; i++) {
177             if (env->QRegs[regnum].ub[i] != 0) {
178                 nonzero_found = true;
179                 break;
180             }
181         }
182         if (!nonzero_found) {
183             return;
184         }
185     }
186 
187     qemu_fprintf(f, "  q%d = ( ", regnum);
188     qemu_fprintf(f, "0x%02x",
189                  env->QRegs[regnum].ub[MAX_VEC_SIZE_BYTES / 8 - 1]);
190     for (int i = MAX_VEC_SIZE_BYTES / 8 - 2; i >= 0; i--) {
191         qemu_fprintf(f, ", 0x%02x", env->QRegs[regnum].ub[i]);
192     }
193     qemu_fprintf(f, " )\n");
194 }
195 
196 void hexagon_debug_qreg(CPUHexagonState *env, int regnum)
197 {
198     print_qreg(stdout, env, regnum, false);
199 }
200 
201 static void hexagon_dump(CPUHexagonState *env, FILE *f, int flags)
202 {
203     HexagonCPU *cpu = env_archcpu(env);
204 
205     if (cpu->lldb_compat) {
206         /*
207          * When comparing with LLDB, it doesn't step through single-cycle
208          * hardware loops the same way.  So, we just skip them here
209          */
210         if (env->gpr[HEX_REG_PC] == env->last_pc_dumped) {
211             return;
212         }
213         env->last_pc_dumped = env->gpr[HEX_REG_PC];
214     }
215 
216     qemu_fprintf(f, "General Purpose Registers = {\n");
217     for (int i = 0; i < 32; i++) {
218         print_reg(f, env, i);
219     }
220     print_reg(f, env, HEX_REG_SA0);
221     print_reg(f, env, HEX_REG_LC0);
222     print_reg(f, env, HEX_REG_SA1);
223     print_reg(f, env, HEX_REG_LC1);
224     print_reg(f, env, HEX_REG_M0);
225     print_reg(f, env, HEX_REG_M1);
226     print_reg(f, env, HEX_REG_USR);
227     print_reg(f, env, HEX_REG_P3_0_ALIASED);
228     print_reg(f, env, HEX_REG_GP);
229     print_reg(f, env, HEX_REG_UGP);
230     print_reg(f, env, HEX_REG_PC);
231 #ifdef CONFIG_USER_ONLY
232     /*
233      * Not modelled in user mode, print junk to minimize the diff's
234      * with LLDB output
235      */
236     qemu_fprintf(f, "  cause = 0x000000db\n");
237     qemu_fprintf(f, "  badva = 0x00000000\n");
238     qemu_fprintf(f, "  cs0 = 0x00000000\n");
239     qemu_fprintf(f, "  cs1 = 0x00000000\n");
240 #else
241     print_reg(f, env, HEX_REG_CAUSE);
242     print_reg(f, env, HEX_REG_BADVA);
243     print_reg(f, env, HEX_REG_CS0);
244     print_reg(f, env, HEX_REG_CS1);
245 #endif
246     qemu_fprintf(f, "}\n");
247 
248     if (flags & CPU_DUMP_FPU) {
249         qemu_fprintf(f, "Vector Registers = {\n");
250         for (int i = 0; i < NUM_VREGS; i++) {
251             print_vreg(f, env, i, true);
252         }
253         for (int i = 0; i < NUM_QREGS; i++) {
254             print_qreg(f, env, i, true);
255         }
256         qemu_fprintf(f, "}\n");
257     }
258 }
259 
260 static void hexagon_dump_state(CPUState *cs, FILE *f, int flags)
261 {
262     HexagonCPU *cpu = HEXAGON_CPU(cs);
263     CPUHexagonState *env = &cpu->env;
264 
265     hexagon_dump(env, f, flags);
266 }
267 
268 void hexagon_debug(CPUHexagonState *env)
269 {
270     hexagon_dump(env, stdout, CPU_DUMP_FPU);
271 }
272 
273 static void hexagon_cpu_set_pc(CPUState *cs, vaddr value)
274 {
275     HexagonCPU *cpu = HEXAGON_CPU(cs);
276     CPUHexagonState *env = &cpu->env;
277     env->gpr[HEX_REG_PC] = value;
278 }
279 
280 static vaddr hexagon_cpu_get_pc(CPUState *cs)
281 {
282     HexagonCPU *cpu = HEXAGON_CPU(cs);
283     CPUHexagonState *env = &cpu->env;
284     return env->gpr[HEX_REG_PC];
285 }
286 
287 static void hexagon_cpu_synchronize_from_tb(CPUState *cs,
288                                             const TranslationBlock *tb)
289 {
290     HexagonCPU *cpu = HEXAGON_CPU(cs);
291     CPUHexagonState *env = &cpu->env;
292     tcg_debug_assert(!(cs->tcg_cflags & CF_PCREL));
293     env->gpr[HEX_REG_PC] = tb->pc;
294 }
295 
296 static bool hexagon_cpu_has_work(CPUState *cs)
297 {
298     return true;
299 }
300 
301 static void hexagon_restore_state_to_opc(CPUState *cs,
302                                          const TranslationBlock *tb,
303                                          const uint64_t *data)
304 {
305     HexagonCPU *cpu = HEXAGON_CPU(cs);
306     CPUHexagonState *env = &cpu->env;
307 
308     env->gpr[HEX_REG_PC] = data[0];
309 }
310 
311 static void hexagon_cpu_reset_hold(Object *obj)
312 {
313     CPUState *cs = CPU(obj);
314     HexagonCPU *cpu = HEXAGON_CPU(cs);
315     HexagonCPUClass *mcc = HEXAGON_CPU_GET_CLASS(cpu);
316     CPUHexagonState *env = &cpu->env;
317 
318     if (mcc->parent_phases.hold) {
319         mcc->parent_phases.hold(obj);
320     }
321 
322     set_default_nan_mode(1, &env->fp_status);
323     set_float_detect_tininess(float_tininess_before_rounding, &env->fp_status);
324 }
325 
326 static void hexagon_cpu_disas_set_info(CPUState *s, disassemble_info *info)
327 {
328     info->print_insn = print_insn_hexagon;
329 }
330 
331 static void hexagon_cpu_realize(DeviceState *dev, Error **errp)
332 {
333     CPUState *cs = CPU(dev);
334     HexagonCPUClass *mcc = HEXAGON_CPU_GET_CLASS(dev);
335     Error *local_err = NULL;
336 
337     cpu_exec_realizefn(cs, &local_err);
338     if (local_err != NULL) {
339         error_propagate(errp, local_err);
340         return;
341     }
342 
343     gdb_register_coprocessor(cs, hexagon_hvx_gdb_read_register,
344                              hexagon_hvx_gdb_write_register,
345                              NUM_VREGS + NUM_QREGS,
346                              "hexagon-hvx.xml", 0);
347 
348     qemu_init_vcpu(cs);
349     cpu_reset(cs);
350 
351     mcc->parent_realize(dev, errp);
352 }
353 
354 static void hexagon_cpu_init(Object *obj)
355 {
356     qdev_property_add_static(DEVICE(obj), &hexagon_lldb_compat_property);
357     qdev_property_add_static(DEVICE(obj), &hexagon_lldb_stack_adjust_property);
358     qdev_property_add_static(DEVICE(obj), &hexagon_short_circuit_property);
359 }
360 
361 #include "hw/core/tcg-cpu-ops.h"
362 
363 static const struct TCGCPUOps hexagon_tcg_ops = {
364     .initialize = hexagon_translate_init,
365     .synchronize_from_tb = hexagon_cpu_synchronize_from_tb,
366     .restore_state_to_opc = hexagon_restore_state_to_opc,
367 };
368 
369 static void hexagon_cpu_class_init(ObjectClass *c, void *data)
370 {
371     HexagonCPUClass *mcc = HEXAGON_CPU_CLASS(c);
372     CPUClass *cc = CPU_CLASS(c);
373     DeviceClass *dc = DEVICE_CLASS(c);
374     ResettableClass *rc = RESETTABLE_CLASS(c);
375 
376     device_class_set_parent_realize(dc, hexagon_cpu_realize,
377                                     &mcc->parent_realize);
378 
379     resettable_class_set_parent_phases(rc, NULL, hexagon_cpu_reset_hold, NULL,
380                                        &mcc->parent_phases);
381 
382     cc->class_by_name = hexagon_cpu_class_by_name;
383     cc->has_work = hexagon_cpu_has_work;
384     cc->dump_state = hexagon_dump_state;
385     cc->set_pc = hexagon_cpu_set_pc;
386     cc->get_pc = hexagon_cpu_get_pc;
387     cc->gdb_read_register = hexagon_gdb_read_register;
388     cc->gdb_write_register = hexagon_gdb_write_register;
389     cc->gdb_num_core_regs = TOTAL_PER_THREAD_REGS;
390     cc->gdb_stop_before_watchpoint = true;
391     cc->gdb_core_xml_file = "hexagon-core.xml";
392     cc->disas_set_info = hexagon_cpu_disas_set_info;
393     cc->tcg_ops = &hexagon_tcg_ops;
394 }
395 
396 #define DEFINE_CPU(type_name, initfn)      \
397     {                                      \
398         .name = type_name,                 \
399         .parent = TYPE_HEXAGON_CPU,        \
400         .instance_init = initfn            \
401     }
402 
403 static const TypeInfo hexagon_cpu_type_infos[] = {
404     {
405         .name = TYPE_HEXAGON_CPU,
406         .parent = TYPE_CPU,
407         .instance_size = sizeof(HexagonCPU),
408         .instance_align = __alignof(HexagonCPU),
409         .instance_init = hexagon_cpu_init,
410         .abstract = true,
411         .class_size = sizeof(HexagonCPUClass),
412         .class_init = hexagon_cpu_class_init,
413     },
414     DEFINE_CPU(TYPE_HEXAGON_CPU_V67,              hexagon_v67_cpu_init),
415     DEFINE_CPU(TYPE_HEXAGON_CPU_V68,              hexagon_v68_cpu_init),
416     DEFINE_CPU(TYPE_HEXAGON_CPU_V69,              hexagon_v69_cpu_init),
417     DEFINE_CPU(TYPE_HEXAGON_CPU_V71,              hexagon_v71_cpu_init),
418     DEFINE_CPU(TYPE_HEXAGON_CPU_V73,              hexagon_v73_cpu_init),
419 };
420 
421 DEFINE_TYPES(hexagon_cpu_type_infos)
422