xref: /openbmc/qemu/target/hexagon/cpu.c (revision 7528ef73)
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         return NULL;
68     }
69     return oc;
70 }
71 
72 static Property hexagon_lldb_compat_property =
73     DEFINE_PROP_BOOL("lldb-compat", HexagonCPU, lldb_compat, false);
74 static Property hexagon_lldb_stack_adjust_property =
75     DEFINE_PROP_UNSIGNED("lldb-stack-adjust", HexagonCPU, lldb_stack_adjust,
76                          0, qdev_prop_uint32, target_ulong);
77 static Property hexagon_short_circuit_property =
78     DEFINE_PROP_BOOL("short-circuit", HexagonCPU, short_circuit, true);
79 
80 const char * const hexagon_regnames[TOTAL_PER_THREAD_REGS] = {
81    "r0", "r1",  "r2",  "r3",  "r4",   "r5",  "r6",  "r7",
82    "r8", "r9",  "r10", "r11", "r12",  "r13", "r14", "r15",
83   "r16", "r17", "r18", "r19", "r20",  "r21", "r22", "r23",
84   "r24", "r25", "r26", "r27", "r28",  "r29", "r30", "r31",
85   "sa0", "lc0", "sa1", "lc1", "p3_0", "c5",  "m0",  "m1",
86   "usr", "pc",  "ugp", "gp",  "cs0",  "cs1", "c14", "c15",
87   "c16", "c17", "c18", "c19", "pkt_cnt",  "insn_cnt", "hvx_cnt", "c23",
88   "c24", "c25", "c26", "c27", "c28",  "c29", "c30", "c31",
89 };
90 
91 /*
92  * One of the main debugging techniques is to use "-d cpu" and compare against
93  * LLDB output when single stepping.  However, the target and qemu put the
94  * stacks at different locations.  This is used to compensate so the diff is
95  * cleaner.
96  */
97 static target_ulong adjust_stack_ptrs(CPUHexagonState *env, target_ulong addr)
98 {
99     HexagonCPU *cpu = env_archcpu(env);
100     target_ulong stack_adjust = cpu->lldb_stack_adjust;
101     target_ulong stack_start = env->stack_start;
102     target_ulong stack_size = 0x10000;
103 
104     if (stack_adjust == 0) {
105         return addr;
106     }
107 
108     if (stack_start + 0x1000 >= addr && addr >= (stack_start - stack_size)) {
109         return addr - stack_adjust;
110     }
111     return addr;
112 }
113 
114 /* HEX_REG_P3_0_ALIASED (aka C4) is an alias for the predicate registers */
115 static target_ulong read_p3_0(CPUHexagonState *env)
116 {
117     int32_t control_reg = 0;
118     int i;
119     for (i = NUM_PREGS - 1; i >= 0; i--) {
120         control_reg <<= 8;
121         control_reg |= env->pred[i] & 0xff;
122     }
123     return control_reg;
124 }
125 
126 static void print_reg(FILE *f, CPUHexagonState *env, int regnum)
127 {
128     target_ulong value;
129 
130     if (regnum == HEX_REG_P3_0_ALIASED) {
131         value = read_p3_0(env);
132     } else {
133         value = regnum < 32 ? adjust_stack_ptrs(env, env->gpr[regnum])
134                             : env->gpr[regnum];
135     }
136 
137     qemu_fprintf(f, "  %s = 0x" TARGET_FMT_lx "\n",
138                  hexagon_regnames[regnum], value);
139 }
140 
141 static void print_vreg(FILE *f, CPUHexagonState *env, int regnum,
142                        bool skip_if_zero)
143 {
144     if (skip_if_zero) {
145         bool nonzero_found = false;
146         for (int i = 0; i < MAX_VEC_SIZE_BYTES; i++) {
147             if (env->VRegs[regnum].ub[i] != 0) {
148                 nonzero_found = true;
149                 break;
150             }
151         }
152         if (!nonzero_found) {
153             return;
154         }
155     }
156 
157     qemu_fprintf(f, "  v%d = ( ", regnum);
158     qemu_fprintf(f, "0x%02x", env->VRegs[regnum].ub[MAX_VEC_SIZE_BYTES - 1]);
159     for (int i = MAX_VEC_SIZE_BYTES - 2; i >= 0; i--) {
160         qemu_fprintf(f, ", 0x%02x", env->VRegs[regnum].ub[i]);
161     }
162     qemu_fprintf(f, " )\n");
163 }
164 
165 void hexagon_debug_vreg(CPUHexagonState *env, int regnum)
166 {
167     print_vreg(stdout, env, regnum, false);
168 }
169 
170 static void print_qreg(FILE *f, CPUHexagonState *env, int regnum,
171                        bool skip_if_zero)
172 {
173     if (skip_if_zero) {
174         bool nonzero_found = false;
175         for (int i = 0; i < MAX_VEC_SIZE_BYTES / 8; i++) {
176             if (env->QRegs[regnum].ub[i] != 0) {
177                 nonzero_found = true;
178                 break;
179             }
180         }
181         if (!nonzero_found) {
182             return;
183         }
184     }
185 
186     qemu_fprintf(f, "  q%d = ( ", regnum);
187     qemu_fprintf(f, "0x%02x",
188                  env->QRegs[regnum].ub[MAX_VEC_SIZE_BYTES / 8 - 1]);
189     for (int i = MAX_VEC_SIZE_BYTES / 8 - 2; i >= 0; i--) {
190         qemu_fprintf(f, ", 0x%02x", env->QRegs[regnum].ub[i]);
191     }
192     qemu_fprintf(f, " )\n");
193 }
194 
195 void hexagon_debug_qreg(CPUHexagonState *env, int regnum)
196 {
197     print_qreg(stdout, env, regnum, false);
198 }
199 
200 static void hexagon_dump(CPUHexagonState *env, FILE *f, int flags)
201 {
202     HexagonCPU *cpu = env_archcpu(env);
203 
204     if (cpu->lldb_compat) {
205         /*
206          * When comparing with LLDB, it doesn't step through single-cycle
207          * hardware loops the same way.  So, we just skip them here
208          */
209         if (env->gpr[HEX_REG_PC] == env->last_pc_dumped) {
210             return;
211         }
212         env->last_pc_dumped = env->gpr[HEX_REG_PC];
213     }
214 
215     qemu_fprintf(f, "General Purpose Registers = {\n");
216     for (int i = 0; i < 32; i++) {
217         print_reg(f, env, i);
218     }
219     print_reg(f, env, HEX_REG_SA0);
220     print_reg(f, env, HEX_REG_LC0);
221     print_reg(f, env, HEX_REG_SA1);
222     print_reg(f, env, HEX_REG_LC1);
223     print_reg(f, env, HEX_REG_M0);
224     print_reg(f, env, HEX_REG_M1);
225     print_reg(f, env, HEX_REG_USR);
226     print_reg(f, env, HEX_REG_P3_0_ALIASED);
227     print_reg(f, env, HEX_REG_GP);
228     print_reg(f, env, HEX_REG_UGP);
229     print_reg(f, env, HEX_REG_PC);
230 #ifdef CONFIG_USER_ONLY
231     /*
232      * Not modelled in user mode, print junk to minimize the diff's
233      * with LLDB output
234      */
235     qemu_fprintf(f, "  cause = 0x000000db\n");
236     qemu_fprintf(f, "  badva = 0x00000000\n");
237     qemu_fprintf(f, "  cs0 = 0x00000000\n");
238     qemu_fprintf(f, "  cs1 = 0x00000000\n");
239 #else
240     print_reg(f, env, HEX_REG_CAUSE);
241     print_reg(f, env, HEX_REG_BADVA);
242     print_reg(f, env, HEX_REG_CS0);
243     print_reg(f, env, HEX_REG_CS1);
244 #endif
245     qemu_fprintf(f, "}\n");
246 
247     if (flags & CPU_DUMP_FPU) {
248         qemu_fprintf(f, "Vector Registers = {\n");
249         for (int i = 0; i < NUM_VREGS; i++) {
250             print_vreg(f, env, i, true);
251         }
252         for (int i = 0; i < NUM_QREGS; i++) {
253             print_qreg(f, env, i, true);
254         }
255         qemu_fprintf(f, "}\n");
256     }
257 }
258 
259 static void hexagon_dump_state(CPUState *cs, FILE *f, int flags)
260 {
261     HexagonCPU *cpu = HEXAGON_CPU(cs);
262     CPUHexagonState *env = &cpu->env;
263 
264     hexagon_dump(env, f, flags);
265 }
266 
267 void hexagon_debug(CPUHexagonState *env)
268 {
269     hexagon_dump(env, stdout, CPU_DUMP_FPU);
270 }
271 
272 static void hexagon_cpu_set_pc(CPUState *cs, vaddr value)
273 {
274     HexagonCPU *cpu = HEXAGON_CPU(cs);
275     CPUHexagonState *env = &cpu->env;
276     env->gpr[HEX_REG_PC] = value;
277 }
278 
279 static vaddr hexagon_cpu_get_pc(CPUState *cs)
280 {
281     HexagonCPU *cpu = HEXAGON_CPU(cs);
282     CPUHexagonState *env = &cpu->env;
283     return env->gpr[HEX_REG_PC];
284 }
285 
286 static void hexagon_cpu_synchronize_from_tb(CPUState *cs,
287                                             const TranslationBlock *tb)
288 {
289     HexagonCPU *cpu = HEXAGON_CPU(cs);
290     CPUHexagonState *env = &cpu->env;
291     tcg_debug_assert(!(cs->tcg_cflags & CF_PCREL));
292     env->gpr[HEX_REG_PC] = tb->pc;
293 }
294 
295 static bool hexagon_cpu_has_work(CPUState *cs)
296 {
297     return true;
298 }
299 
300 static void hexagon_restore_state_to_opc(CPUState *cs,
301                                          const TranslationBlock *tb,
302                                          const uint64_t *data)
303 {
304     HexagonCPU *cpu = HEXAGON_CPU(cs);
305     CPUHexagonState *env = &cpu->env;
306 
307     env->gpr[HEX_REG_PC] = data[0];
308 }
309 
310 static void hexagon_cpu_reset_hold(Object *obj)
311 {
312     CPUState *cs = CPU(obj);
313     HexagonCPU *cpu = HEXAGON_CPU(cs);
314     HexagonCPUClass *mcc = HEXAGON_CPU_GET_CLASS(cpu);
315     CPUHexagonState *env = &cpu->env;
316 
317     if (mcc->parent_phases.hold) {
318         mcc->parent_phases.hold(obj);
319     }
320 
321     set_default_nan_mode(1, &env->fp_status);
322     set_float_detect_tininess(float_tininess_before_rounding, &env->fp_status);
323 }
324 
325 static void hexagon_cpu_disas_set_info(CPUState *s, disassemble_info *info)
326 {
327     info->print_insn = print_insn_hexagon;
328 }
329 
330 static void hexagon_cpu_realize(DeviceState *dev, Error **errp)
331 {
332     CPUState *cs = CPU(dev);
333     HexagonCPUClass *mcc = HEXAGON_CPU_GET_CLASS(dev);
334     Error *local_err = NULL;
335 
336     cpu_exec_realizefn(cs, &local_err);
337     if (local_err != NULL) {
338         error_propagate(errp, local_err);
339         return;
340     }
341 
342     gdb_register_coprocessor(cs, hexagon_hvx_gdb_read_register,
343                              hexagon_hvx_gdb_write_register,
344                              NUM_VREGS + NUM_QREGS,
345                              "hexagon-hvx.xml", 0);
346 
347     qemu_init_vcpu(cs);
348     cpu_reset(cs);
349 
350     mcc->parent_realize(dev, errp);
351 }
352 
353 static void hexagon_cpu_init(Object *obj)
354 {
355     qdev_property_add_static(DEVICE(obj), &hexagon_lldb_compat_property);
356     qdev_property_add_static(DEVICE(obj), &hexagon_lldb_stack_adjust_property);
357     qdev_property_add_static(DEVICE(obj), &hexagon_short_circuit_property);
358 }
359 
360 #include "hw/core/tcg-cpu-ops.h"
361 
362 static const struct TCGCPUOps hexagon_tcg_ops = {
363     .initialize = hexagon_translate_init,
364     .synchronize_from_tb = hexagon_cpu_synchronize_from_tb,
365     .restore_state_to_opc = hexagon_restore_state_to_opc,
366 };
367 
368 static void hexagon_cpu_class_init(ObjectClass *c, void *data)
369 {
370     HexagonCPUClass *mcc = HEXAGON_CPU_CLASS(c);
371     CPUClass *cc = CPU_CLASS(c);
372     DeviceClass *dc = DEVICE_CLASS(c);
373     ResettableClass *rc = RESETTABLE_CLASS(c);
374 
375     device_class_set_parent_realize(dc, hexagon_cpu_realize,
376                                     &mcc->parent_realize);
377 
378     resettable_class_set_parent_phases(rc, NULL, hexagon_cpu_reset_hold, NULL,
379                                        &mcc->parent_phases);
380 
381     cc->class_by_name = hexagon_cpu_class_by_name;
382     cc->has_work = hexagon_cpu_has_work;
383     cc->dump_state = hexagon_dump_state;
384     cc->set_pc = hexagon_cpu_set_pc;
385     cc->get_pc = hexagon_cpu_get_pc;
386     cc->gdb_read_register = hexagon_gdb_read_register;
387     cc->gdb_write_register = hexagon_gdb_write_register;
388     cc->gdb_num_core_regs = TOTAL_PER_THREAD_REGS;
389     cc->gdb_stop_before_watchpoint = true;
390     cc->gdb_core_xml_file = "hexagon-core.xml";
391     cc->disas_set_info = hexagon_cpu_disas_set_info;
392     cc->tcg_ops = &hexagon_tcg_ops;
393 }
394 
395 #define DEFINE_CPU(type_name, initfn)      \
396     {                                      \
397         .name = type_name,                 \
398         .parent = TYPE_HEXAGON_CPU,        \
399         .instance_init = initfn            \
400     }
401 
402 static const TypeInfo hexagon_cpu_type_infos[] = {
403     {
404         .name = TYPE_HEXAGON_CPU,
405         .parent = TYPE_CPU,
406         .instance_size = sizeof(HexagonCPU),
407         .instance_align = __alignof(HexagonCPU),
408         .instance_init = hexagon_cpu_init,
409         .abstract = true,
410         .class_size = sizeof(HexagonCPUClass),
411         .class_init = hexagon_cpu_class_init,
412     },
413     DEFINE_CPU(TYPE_HEXAGON_CPU_V67,              hexagon_v67_cpu_init),
414     DEFINE_CPU(TYPE_HEXAGON_CPU_V68,              hexagon_v68_cpu_init),
415     DEFINE_CPU(TYPE_HEXAGON_CPU_V69,              hexagon_v69_cpu_init),
416     DEFINE_CPU(TYPE_HEXAGON_CPU_V71,              hexagon_v71_cpu_init),
417     DEFINE_CPU(TYPE_HEXAGON_CPU_V73,              hexagon_v73_cpu_init),
418 };
419 
420 DEFINE_TYPES(hexagon_cpu_type_infos)
421