target/hexagon/cpu.c

   1 /*
   2  *  Copyright(c) 2019-2021 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
  27 static void hexagon_v67_cpu_init(Object *obj)
  28 {
  29 }
  30
  31 static ObjectClass *hexagon_cpu_class_by_name(const char *cpu_model)
  32 {
  33     ObjectClass *oc;
  34     char *typename;
  35     char **cpuname;
  36
  37     cpuname = g_strsplit(cpu_model, ",", 1);
  38     typename = g_strdup_printf(HEXAGON_CPU_TYPE_NAME("%s"), cpuname[0]);
  39     oc = object_class_by_name(typename);
  40     g_strfreev(cpuname);
  41     g_free(typename);
  42     if (!oc || !object_class_dynamic_cast(oc, TYPE_HEXAGON_CPU) ||
  43         object_class_is_abstract(oc)) {
  44         return NULL;
  45     }
  46     return oc;
  47 }
  48
  49 static Property hexagon_lldb_compat_property =
  50     DEFINE_PROP_BOOL("lldb-compat", HexagonCPU, lldb_compat, false);
  51 static Property hexagon_lldb_stack_adjust_property =
  52     DEFINE_PROP_UNSIGNED("lldb-stack-adjust", HexagonCPU, lldb_stack_adjust,
  53                          0, qdev_prop_uint32, target_ulong);
  54
  55 const char * const hexagon_regnames[TOTAL_PER_THREAD_REGS] = {
  56    "r0", "r1",  "r2",  "r3",  "r4",   "r5",  "r6",  "r7",
  57    "r8", "r9",  "r10", "r11", "r12",  "r13", "r14", "r15",
  58   "r16", "r17", "r18", "r19", "r20",  "r21", "r22", "r23",
  59   "r24", "r25", "r26", "r27", "r28",  "r29", "r30", "r31",
  60   "sa0", "lc0", "sa1", "lc1", "p3_0", "c5",  "m0",  "m1",
  61   "usr", "pc",  "ugp", "gp",  "cs0",  "cs1", "c14", "c15",
  62   "c16", "c17", "c18", "c19", "pkt_cnt",  "insn_cnt", "c22", "c23",
  63   "c24", "c25", "c26", "c27", "c28",  "c29", "c30", "c31",
  64 };
  65
  66 /*
  67  * One of the main debugging techniques is to use "-d cpu" and compare against
  68  * LLDB output when single stepping.  However, the target and qemu put the
  69  * stacks at different locations.  This is used to compensate so the diff is
  70  * cleaner.
  71  */
  72 static target_ulong adjust_stack_ptrs(CPUHexagonState *env, target_ulong addr)
  73 {
  74     HexagonCPU *cpu = env_archcpu(env);
  75     target_ulong stack_adjust = cpu->lldb_stack_adjust;
  76     target_ulong stack_start = env->stack_start;
  77     target_ulong stack_size = 0x10000;
  78
  79     if (stack_adjust == 0) {
  80         return addr;
  81     }
  82
  83     if (stack_start + 0x1000 >= addr && addr >= (stack_start - stack_size)) {
  84         return addr - stack_adjust;
  85     }
  86     return addr;
  87 }
  88
  89 /* HEX_REG_P3_0 (aka C4) is an alias for the predicate registers */
  90 static target_ulong read_p3_0(CPUHexagonState *env)
  91 {
  92     int32_t control_reg = 0;
  93     int i;
  94     for (i = NUM_PREGS - 1; i >= 0; i--) {
  95         control_reg <<= 8;
  96         control_reg |= env->pred[i] & 0xff;
  97     }
  98     return control_reg;
  99 }
 100
 101 static void print_reg(FILE *f, CPUHexagonState *env, int regnum)
 102 {
 103     target_ulong value;
 104
 105     if (regnum == HEX_REG_P3_0) {
 106         value = read_p3_0(env);
 107     } else {
 108         value = regnum < 32 ? adjust_stack_ptrs(env, env->gpr[regnum])
 109                             : env->gpr[regnum];
 110     }
 111
 112     qemu_fprintf(f, "  %s = 0x" TARGET_FMT_lx "\n",
 113                  hexagon_regnames[regnum], value);
 114 }
 115
 116 static void hexagon_dump(CPUHexagonState *env, FILE *f)
 117 {
 118     HexagonCPU *cpu = env_archcpu(env);
 119
 120     if (cpu->lldb_compat) {
 121         /*
 122          * When comparing with LLDB, it doesn't step through single-cycle
 123          * hardware loops the same way.  So, we just skip them here
 124          */
 125         if (env->gpr[HEX_REG_PC] == env->last_pc_dumped) {
 126             return;
 127         }
 128         env->last_pc_dumped = env->gpr[HEX_REG_PC];
 129     }
 130
 131     qemu_fprintf(f, "General Purpose Registers = {\n");
 132     for (int i = 0; i < 32; i++) {
 133         print_reg(f, env, i);
 134     }
 135     print_reg(f, env, HEX_REG_SA0);
 136     print_reg(f, env, HEX_REG_LC0);
 137     print_reg(f, env, HEX_REG_SA1);
 138     print_reg(f, env, HEX_REG_LC1);
 139     print_reg(f, env, HEX_REG_M0);
 140     print_reg(f, env, HEX_REG_M1);
 141     print_reg(f, env, HEX_REG_USR);
 142     print_reg(f, env, HEX_REG_P3_0);
 143     print_reg(f, env, HEX_REG_GP);
 144     print_reg(f, env, HEX_REG_UGP);
 145     print_reg(f, env, HEX_REG_PC);
 146 #ifdef CONFIG_USER_ONLY
 147     /*
 148      * Not modelled in user mode, print junk to minimize the diff's
 149      * with LLDB output
 150      */
 151     qemu_fprintf(f, "  cause = 0x000000db\n");
 152     qemu_fprintf(f, "  badva = 0x00000000\n");
 153     qemu_fprintf(f, "  cs0 = 0x00000000\n");
 154     qemu_fprintf(f, "  cs1 = 0x00000000\n");
 155 #else
 156     print_reg(f, env, HEX_REG_CAUSE);
 157     print_reg(f, env, HEX_REG_BADVA);
 158     print_reg(f, env, HEX_REG_CS0);
 159     print_reg(f, env, HEX_REG_CS1);
 160 #endif
 161     qemu_fprintf(f, "}\n");
 162 }
 163
 164 static void hexagon_dump_state(CPUState *cs, FILE *f, int flags)
 165 {
 166     HexagonCPU *cpu = HEXAGON_CPU(cs);
 167     CPUHexagonState *env = &cpu->env;
 168
 169     hexagon_dump(env, f);
 170 }
 171
 172 void hexagon_debug(CPUHexagonState *env)
 173 {
 174     hexagon_dump(env, stdout);
 175 }
 176
 177 static void hexagon_cpu_set_pc(CPUState *cs, vaddr value)
 178 {
 179     HexagonCPU *cpu = HEXAGON_CPU(cs);
 180     CPUHexagonState *env = &cpu->env;
 181     env->gpr[HEX_REG_PC] = value;
 182 }
 183
 184 static void hexagon_cpu_synchronize_from_tb(CPUState *cs,
 185                                             const TranslationBlock *tb)
 186 {
 187     HexagonCPU *cpu = HEXAGON_CPU(cs);
 188     CPUHexagonState *env = &cpu->env;
 189     env->gpr[HEX_REG_PC] = tb->pc;
 190 }
 191
 192 static bool hexagon_cpu_has_work(CPUState *cs)
 193 {
 194     return true;
 195 }
 196
 197 void restore_state_to_opc(CPUHexagonState *env, TranslationBlock *tb,
 198                           target_ulong *data)
 199 {
 200     env->gpr[HEX_REG_PC] = data[0];
 201 }
 202
 203 static void hexagon_cpu_reset(DeviceState *dev)
 204 {
 205     CPUState *cs = CPU(dev);
 206     HexagonCPU *cpu = HEXAGON_CPU(cs);
 207     HexagonCPUClass *mcc = HEXAGON_CPU_GET_CLASS(cpu);
 208     CPUHexagonState *env = &cpu->env;
 209
 210     mcc->parent_reset(dev);
 211
 212     set_default_nan_mode(1, &env->fp_status);
 213     set_float_detect_tininess(float_tininess_before_rounding, &env->fp_status);
 214 }
 215
 216 static void hexagon_cpu_disas_set_info(CPUState *s, disassemble_info *info)
 217 {
 218     info->print_insn = print_insn_hexagon;
 219 }
 220
 221 static void hexagon_cpu_realize(DeviceState *dev, Error **errp)
 222 {
 223     CPUState *cs = CPU(dev);
 224     HexagonCPUClass *mcc = HEXAGON_CPU_GET_CLASS(dev);
 225     Error *local_err = NULL;
 226
 227     cpu_exec_realizefn(cs, &local_err);
 228     if (local_err != NULL) {
 229         error_propagate(errp, local_err);
 230         return;
 231     }
 232
 233     qemu_init_vcpu(cs);
 234     cpu_reset(cs);
 235
 236     mcc->parent_realize(dev, errp);
 237 }
 238
 239 static void hexagon_cpu_init(Object *obj)
 240 {
 241     HexagonCPU *cpu = HEXAGON_CPU(obj);
 242
 243     cpu_set_cpustate_pointers(cpu);
 244     qdev_property_add_static(DEVICE(obj), &hexagon_lldb_compat_property);
 245     qdev_property_add_static(DEVICE(obj), &hexagon_lldb_stack_adjust_property);
 246 }
 247
 248 static bool hexagon_tlb_fill(CPUState *cs, vaddr address, int size,
 249                              MMUAccessType access_type, int mmu_idx,
 250                              bool probe, uintptr_t retaddr)
 251 {
 252 #ifdef CONFIG_USER_ONLY
 253     switch (access_type) {
 254     case MMU_INST_FETCH:
 255         cs->exception_index = HEX_EXCP_FETCH_NO_UPAGE;
 256         break;
 257     case MMU_DATA_LOAD:
 258         cs->exception_index = HEX_EXCP_PRIV_NO_UREAD;
 259         break;
 260     case MMU_DATA_STORE:
 261         cs->exception_index = HEX_EXCP_PRIV_NO_UWRITE;
 262         break;
 263     }
 264     cpu_loop_exit_restore(cs, retaddr);
 265 #else
 266 #error System mode not implemented for Hexagon
 267 #endif
 268 }
 269
 270 #include "hw/core/tcg-cpu-ops.h"
 271
 272 static const struct TCGCPUOps hexagon_tcg_ops = {
 273     .initialize = hexagon_translate_init,
 274     .synchronize_from_tb = hexagon_cpu_synchronize_from_tb,
 275     .tlb_fill = hexagon_tlb_fill,
 276 };
 277
 278 static void hexagon_cpu_class_init(ObjectClass *c, void *data)
 279 {
 280     HexagonCPUClass *mcc = HEXAGON_CPU_CLASS(c);
 281     CPUClass *cc = CPU_CLASS(c);
 282     DeviceClass *dc = DEVICE_CLASS(c);
 283
 284     device_class_set_parent_realize(dc, hexagon_cpu_realize,
 285                                     &mcc->parent_realize);
 286
 287     device_class_set_parent_reset(dc, hexagon_cpu_reset, &mcc->parent_reset);
 288
 289     cc->class_by_name = hexagon_cpu_class_by_name;
 290     cc->has_work = hexagon_cpu_has_work;
 291     cc->dump_state = hexagon_dump_state;
 292     cc->set_pc = hexagon_cpu_set_pc;
 293     cc->gdb_read_register = hexagon_gdb_read_register;
 294     cc->gdb_write_register = hexagon_gdb_write_register;
 295     cc->gdb_num_core_regs = TOTAL_PER_THREAD_REGS;
 296     cc->gdb_stop_before_watchpoint = true;
 297     cc->disas_set_info = hexagon_cpu_disas_set_info;
 298     cc->tcg_ops = &hexagon_tcg_ops;
 299 }
 300
 301 #define DEFINE_CPU(type_name, initfn)      \
 302     {                                      \
 303         .name = type_name,                 \
 304         .parent = TYPE_HEXAGON_CPU,        \
 305         .instance_init = initfn            \
 306     }
 307
 308 static const TypeInfo hexagon_cpu_type_infos[] = {
 309     {
 310         .name = TYPE_HEXAGON_CPU,
 311         .parent = TYPE_CPU,
 312         .instance_size = sizeof(HexagonCPU),
 313         .instance_init = hexagon_cpu_init,
 314         .abstract = true,
 315         .class_size = sizeof(HexagonCPUClass),
 316         .class_init = hexagon_cpu_class_init,
 317     },
 318     DEFINE_CPU(TYPE_HEXAGON_CPU_V67,              hexagon_v67_cpu_init),
 319 };
 320
 321 DEFINE_TYPES(hexagon_cpu_type_infos)