target/loongarch/gdbstub.c

   1 /*
   2  * LOONGARCH gdb server stub
   3  *
   4  * Copyright (c) 2021 Loongson Technology Corporation Limited
   5  *
   6  * SPDX-License-Identifier: LGPL-2.1+
   7  */
   8
   9 #include "qemu/osdep.h"
  10 #include "cpu.h"
  11 #include "internals.h"
  12 #include "exec/gdbstub.h"
  13 #include "gdbstub/helpers.h"
  14 #include "vec.h"
  15
  16 uint64_t read_fcc(CPULoongArchState *env)
  17 {
  18     uint64_t ret = 0;
  19
  20     for (int i = 0; i < 8; ++i) {
  21         ret |= (uint64_t)env->cf[i] << (i * 8);
  22     }
  23
  24     return ret;
  25 }
  26
  27 void write_fcc(CPULoongArchState *env, uint64_t val)
  28 {
  29     for (int i = 0; i < 8; ++i) {
  30         env->cf[i] = (val >> (i * 8)) & 1;
  31     }
  32 }
  33
  34 int loongarch_cpu_gdb_read_register(CPUState *cs, GByteArray *mem_buf, int n)
  35 {
  36     LoongArchCPU *cpu = LOONGARCH_CPU(cs);
  37     CPULoongArchState *env = &cpu->env;
  38     uint64_t val;
  39
  40     if (0 <= n && n < 32) {
  41         val = env->gpr[n];
  42     } else if (n == 32) {
  43         /* orig_a0 */
  44         val = 0;
  45     } else if (n == 33) {
  46         val = env->pc;
  47     } else if (n == 34) {
  48         val = env->CSR_BADV;
  49     }
  50
  51     if (0 <= n && n <= 34) {
  52         if (is_la64(env)) {
  53             return gdb_get_reg64(mem_buf, val);
  54         } else {
  55             return gdb_get_reg32(mem_buf, val);
  56         }
  57     }
  58     return 0;
  59 }
  60
  61 int loongarch_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
  62 {
  63     LoongArchCPU *cpu = LOONGARCH_CPU(cs);
  64     CPULoongArchState *env = &cpu->env;
  65     target_ulong tmp;
  66     int read_length;
  67     int length = 0;
  68
  69     if (is_la64(env)) {
  70         tmp = ldq_p(mem_buf);
  71         read_length = 8;
  72     } else {
  73         tmp = ldl_p(mem_buf);
  74         read_length = 4;
  75     }
  76
  77     if (0 <= n && n < 32) {
  78         env->gpr[n] = tmp;
  79         length = read_length;
  80     } else if (n == 33) {
  81         set_pc(env, tmp);
  82         length = read_length;
  83     }
  84     return length;
  85 }
  86
  87 static int loongarch_gdb_get_fpu(CPULoongArchState *env,
  88                                  GByteArray *mem_buf, int n)
  89 {
  90     if (0 <= n && n < 32) {
  91         return gdb_get_reg64(mem_buf, env->fpr[n].vreg.D(0));
  92     } else if (32 <= n && n < 40) {
  93         return gdb_get_reg8(mem_buf, env->cf[n - 32]);
  94     } else if (n == 40) {
  95         return gdb_get_reg32(mem_buf, env->fcsr0);
  96     }
  97     return 0;
  98 }
  99
 100 static int loongarch_gdb_set_fpu(CPULoongArchState *env,
 101                                  uint8_t *mem_buf, int n)
 102 {
 103     int length = 0;
 104
 105     if (0 <= n && n < 32) {
 106         env->fpr[n].vreg.D(0) = ldq_p(mem_buf);
 107         length = 8;
 108     } else if (32 <= n && n < 40) {
 109         env->cf[n - 32] = ldub_p(mem_buf);
 110         length = 1;
 111     } else if (n == 40) {
 112         env->fcsr0 = ldl_p(mem_buf);
 113         length = 4;
 114     }
 115     return length;
 116 }
 117
 118 void loongarch_cpu_register_gdb_regs_for_features(CPUState *cs)
 119 {
 120     gdb_register_coprocessor(cs, loongarch_gdb_get_fpu, loongarch_gdb_set_fpu,
 121                              41, "loongarch-fpu.xml", 0);
 122 }