gdb/ppc-nbsd-nat.c

   1 /* Native-dependent code for NetBSD/powerpc.
   2
   3    Copyright (C) 2002-2020 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 #include "defs.h"
  25
  26 #include <sys/types.h>
  27 #include <sys/ptrace.h>
  28 #include <machine/reg.h>
  29 #include <machine/frame.h>
  30 #include <machine/pcb.h>
  31
  32 #include "gdbcore.h"
  33 #include "inferior.h"
  34 #include "regcache.h"
  35
  36 #include "ppc-tdep.h"
  37 #include "ppc-nbsd-tdep.h"
  38 #include "bsd-kvm.h"
  39 #include "inf-ptrace.h"
  40
  41 struct ppc_nbsd_nat_target final : public inf_ptrace_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   struct gdbarch_tdep *tdep = 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   struct gdbarch_tdep *tdep = 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
  95   if (regnum == -1 || getregs_supplies (gdbarch, regnum))
  96     {
  97       struct reg regs;
  98
  99       if (ptrace (PT_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
 100         perror_with_name (_("Couldn't get registers"));
 101
 102       ppc_supply_gregset (&ppcnbsd_gregset, regcache,
 103                           regnum, &regs, sizeof regs);
 104     }
 105
 106   if (regnum == -1 || getfpregs_supplies (gdbarch, regnum))
 107     {
 108       struct fpreg fpregs;
 109
 110       if (ptrace (PT_GETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 111         perror_with_name (_("Couldn't get FP registers"));
 112
 113       ppc_supply_fpregset (&ppcnbsd_fpregset, regcache,
 114                            regnum, &fpregs, sizeof fpregs);
 115     }
 116 }
 117
 118 void
 119 ppc_nbsd_nat_target::store_registers (struct regcache *regcache, int regnum)
 120 {
 121   struct gdbarch *gdbarch = regcache->arch ();
 122   pid_t pid = regcache->ptid ().pid ();
 123
 124   if (regnum == -1 || getregs_supplies (gdbarch, regnum))
 125     {
 126       struct reg regs;
 127
 128       if (ptrace (PT_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
 129         perror_with_name (_("Couldn't get registers"));
 130
 131       ppc_collect_gregset (&ppcnbsd_gregset, regcache,
 132                            regnum, &regs, sizeof regs);
 133
 134       if (ptrace (PT_SETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
 135         perror_with_name (_("Couldn't write registers"));
 136     }
 137
 138   if (regnum == -1 || getfpregs_supplies (gdbarch, regnum))
 139     {
 140       struct fpreg fpregs;
 141
 142       if (ptrace (PT_GETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 143         perror_with_name (_("Couldn't get FP registers"));
 144
 145       ppc_collect_fpregset (&ppcnbsd_fpregset, regcache,
 146                             regnum, &fpregs, sizeof fpregs);
 147
 148       if (ptrace (PT_SETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 149         perror_with_name (_("Couldn't set FP registers"));
 150     }
 151 }
 152
 153 static int
 154 ppcnbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
 155 {
 156   struct switchframe sf;
 157   struct callframe cf;
 158   struct gdbarch *gdbarch = regcache->arch ();
 159   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 160   int i;
 161
 162   /* The stack pointer shouldn't be zero.  */
 163   if (pcb->pcb_sp == 0)
 164     return 0;
 165
 166   read_memory (pcb->pcb_sp, (gdb_byte *)&sf, sizeof sf);
 167   regcache->raw_supply (tdep->ppc_cr_regnum, &sf.cr);
 168   regcache->raw_supply (tdep->ppc_gp0_regnum + 2, &sf.fixreg2);
 169   for (i = 0 ; i < 19 ; i++)
 170     regcache->raw_supply (tdep->ppc_gp0_regnum + 13 + i, &sf.fixreg[i]);
 171
 172   read_memory(sf.sp, (gdb_byte *)&cf, sizeof(cf));
 173   regcache->raw_supply (tdep->ppc_gp0_regnum + 30, &cf.r30);
 174   regcache->raw_supply (tdep->ppc_gp0_regnum + 31, &cf.r31);
 175   regcache->raw_supply (tdep->ppc_gp0_regnum + 1, &cf.sp);
 176
 177   read_memory(cf.sp, (gdb_byte *)&cf, sizeof(cf));
 178   regcache->raw_supply (tdep->ppc_lr_regnum, &cf.lr);
 179   regcache->raw_supply (gdbarch_pc_regnum (gdbarch), &cf.lr);
 180
 181   return 1;
 182 }
 183
 184 void _initialize_ppcnbsd_nat ();
 185 void
 186 _initialize_ppcnbsd_nat ()
 187 {
 188   /* Support debugging kernel virtual memory images.  */
 189   bsd_kvm_add_target (ppcnbsd_supply_pcb);
 190
 191   add_inf_child_target (&the_ppc_nbsd_nat_target);
 192 }