gdb/ppc-netbsd-nat.c

   1 /* Native-dependent code for NetBSD/powerpc.
   2
   3    Copyright (C) 2002-2024 Free Software Foundation, Inc.
   4
   5    Contributed by Wasabi Systems, Inc.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  21
  22 /* We define this to get types like register_t.  */
  23 #define _KERNTYPES
  24
  25 #include <sys/types.h>
  26 #include <sys/ptrace.h>
  27 #include <machine/reg.h>
  28 #include <machine/frame.h>
  29 #include <machine/pcb.h>
  30
  31 #include "gdbcore.h"
  32 #include "inferior.h"
  33 #include "regcache.h"
  34
  35 #include "ppc-tdep.h"
  36 #include "ppc-netbsd-tdep.h"
  37 #include "bsd-kvm.h"
  38 #include "inf-ptrace.h"
  39 #include "netbsd-nat.h"
  40
  41 struct ppc_nbsd_nat_target final : public nbsd_nat_target
  42 {
  43   void fetch_registers (struct regcache *, int) override;
  44   void store_registers (struct regcache *, int) override;
  45 };
  46
  47 static ppc_nbsd_nat_target the_ppc_nbsd_nat_target;
  48
  49 /* Returns true if PT_GETREGS fetches this register.  */
  50
  51 static int
  52 getregs_supplies (struct gdbarch *gdbarch, int regnum)
  53 {
  54   ppc_gdbarch_tdep *tdep = gdbarch_tdep<ppc_gdbarch_tdep> (gdbarch);
  55
  56   return ((regnum >= tdep->ppc_gp0_regnum
  57            && regnum < tdep->ppc_gp0_regnum + ppc_num_gprs)
  58           || regnum == tdep->ppc_lr_regnum
  59           || regnum == tdep->ppc_cr_regnum
  60           || regnum == tdep->ppc_xer_regnum
  61           || regnum == tdep->ppc_ctr_regnum
  62           || regnum == gdbarch_pc_regnum (gdbarch));
  63 }
  64
  65 /* Like above, but for PT_GETFPREGS.  */
  66
  67 static int
  68 getfpregs_supplies (struct gdbarch *gdbarch, int regnum)
  69 {
  70   ppc_gdbarch_tdep *tdep = gdbarch_tdep<ppc_gdbarch_tdep> (gdbarch);
  71
  72   /* FIXME: jimb/2004-05-05: Some PPC variants don't have floating
  73      point registers.  Traditionally, GDB's register set has still
  74      listed the floating point registers for such machines, so this
  75      code is harmless.  However, the new E500 port actually omits the
  76      floating point registers entirely from the register set --- they
  77      don't even have register numbers assigned to them.
  78
  79      It's not clear to me how best to update this code, so this assert
  80      will alert the first person to encounter the NetBSD/E500
  81      combination to the problem.  */
  82   gdb_assert (ppc_floating_point_unit_p (gdbarch));
  83
  84   return ((regnum >= tdep->ppc_fp0_regnum
  85            && regnum < tdep->ppc_fp0_regnum + ppc_num_fprs)
  86           || regnum == tdep->ppc_fpscr_regnum);
  87 }
  88
  89 void
  90 ppc_nbsd_nat_target::fetch_registers (struct regcache *regcache, int regnum)
  91 {
  92   struct gdbarch *gdbarch = regcache->arch ();
  93   pid_t pid = regcache->ptid ().pid ();
  94   int lwp = regcache->ptid ().lwp ();
  95
  96   if (regnum == -1 || getregs_supplies (gdbarch, regnum))
  97     {
  98       struct reg regs;
  99
 100       if (ptrace (PT_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, lwp) == -1)
 101         perror_with_name (_("Couldn't get registers"));
 102
 103       ppc_supply_gregset (&ppcnbsd_gregset, regcache,
 104                           regnum, &regs, sizeof regs);
 105     }
 106
 107   if (regnum == -1 || getfpregs_supplies (gdbarch, regnum))
 108     {
 109       struct fpreg fpregs;
 110
 111       if (ptrace (PT_GETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, lwp) == -1)
 112         perror_with_name (_("Couldn't get FP registers"));
 113
 114       ppc_supply_fpregset (&ppcnbsd_fpregset, regcache,
 115                            regnum, &fpregs, sizeof fpregs);
 116     }
 117 }
 118
 119 void
 120 ppc_nbsd_nat_target::store_registers (struct regcache *regcache, int regnum)
 121 {
 122   struct gdbarch *gdbarch = regcache->arch ();
 123   pid_t pid = regcache->ptid ().pid ();
 124   int lwp = regcache->ptid ().lwp ();
 125
 126   if (regnum == -1 || getregs_supplies (gdbarch, regnum))
 127     {
 128       struct reg regs;
 129
 130       if (ptrace (PT_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, lwp) == -1)
 131         perror_with_name (_("Couldn't get registers"));
 132
 133       ppc_collect_gregset (&ppcnbsd_gregset, regcache,
 134                            regnum, &regs, sizeof regs);
 135
 136       if (ptrace (PT_SETREGS, pid, (PTRACE_TYPE_ARG3) &regs, lwp) == -1)
 137         perror_with_name (_("Couldn't write registers"));
 138     }
 139
 140   if (regnum == -1 || getfpregs_supplies (gdbarch, regnum))
 141     {
 142       struct fpreg fpregs;
 143
 144       if (ptrace (PT_GETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, lwp) == -1)
 145         perror_with_name (_("Couldn't get FP registers"));
 146
 147       ppc_collect_fpregset (&ppcnbsd_fpregset, regcache,
 148                             regnum, &fpregs, sizeof fpregs);
 149
 150       if (ptrace (PT_SETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, lwp) == -1)
 151         perror_with_name (_("Couldn't set FP registers"));
 152     }
 153 }
 154
 155 static int
 156 ppcnbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
 157 {
 158   struct switchframe sf;
 159   struct callframe cf;
 160   struct gdbarch *gdbarch = regcache->arch ();
 161   ppc_gdbarch_tdep *tdep = gdbarch_tdep<ppc_gdbarch_tdep> (gdbarch);
 162   int i;
 163
 164   /* The stack pointer shouldn't be zero.  */
 165   if (pcb->pcb_sp == 0)
 166     return 0;
 167
 168   read_memory (pcb->pcb_sp, (gdb_byte *)&sf, sizeof sf);
 169   regcache->raw_supply (tdep->ppc_cr_regnum, &sf.cr);
 170   regcache->raw_supply (tdep->ppc_gp0_regnum + 2, &sf.fixreg2);
 171   for (i = 0 ; i < 19 ; i++)
 172     regcache->raw_supply (tdep->ppc_gp0_regnum + 13 + i, &sf.fixreg[i]);
 173
 174   read_memory(sf.sp, (gdb_byte *)&cf, sizeof(cf));
 175   regcache->raw_supply (tdep->ppc_gp0_regnum + 30, &cf.r30);
 176   regcache->raw_supply (tdep->ppc_gp0_regnum + 31, &cf.r31);
 177   regcache->raw_supply (tdep->ppc_gp0_regnum + 1, &cf.sp);
 178
 179   read_memory(cf.sp, (gdb_byte *)&cf, sizeof(cf));
 180   regcache->raw_supply (tdep->ppc_lr_regnum, &cf.lr);
 181   regcache->raw_supply (gdbarch_pc_regnum (gdbarch), &cf.lr);
 182
 183   return 1;
 184 }
 185
 186 void _initialize_ppcnbsd_nat ();
 187 void
 188 _initialize_ppcnbsd_nat ()
 189 {
 190   /* Support debugging kernel virtual memory images.  */
 191   bsd_kvm_add_target (ppcnbsd_supply_pcb);
 192
 193   add_inf_child_target (&the_ppc_nbsd_nat_target);
 194 }