gdb/ppc-nbsd-nat.c

   1 /* Native-dependent code for NetBSD/powerpc.
   2
   3    Copyright (C) 2002-2017 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 #include "defs.h"
  23
  24 #include <sys/types.h>
  25 #include <sys/ptrace.h>
  26 #include <machine/reg.h>
  27 #include <machine/frame.h>
  28 #include <machine/pcb.h>
  29
  30 #include "gdbcore.h"
  31 #include "inferior.h"
  32 #include "regcache.h"
  33
  34 #include "ppc-tdep.h"
  35 #include "ppc-nbsd-tdep.h"
  36 #include "bsd-kvm.h"
  37 #include "inf-ptrace.h"
  38
  39 /* Returns true if PT_GETREGS fetches this register.  */
  40
  41 static int
  42 getregs_supplies (struct gdbarch *gdbarch, int regnum)
  43 {
  44   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
  45
  46   return ((regnum >= tdep->ppc_gp0_regnum
  47            && regnum < tdep->ppc_gp0_regnum + ppc_num_gprs)
  48           || regnum == tdep->ppc_lr_regnum
  49           || regnum == tdep->ppc_cr_regnum
  50           || regnum == tdep->ppc_xer_regnum
  51           || regnum == tdep->ppc_ctr_regnum
  52           || regnum == gdbarch_pc_regnum (gdbarch));
  53 }
  54
  55 /* Like above, but for PT_GETFPREGS.  */
  56
  57 static int
  58 getfpregs_supplies (struct gdbarch *gdbarch, int regnum)
  59 {
  60   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
  61
  62   /* FIXME: jimb/2004-05-05: Some PPC variants don't have floating
  63      point registers.  Traditionally, GDB's register set has still
  64      listed the floating point registers for such machines, so this
  65      code is harmless.  However, the new E500 port actually omits the
  66      floating point registers entirely from the register set --- they
  67      don't even have register numbers assigned to them.
  68
  69      It's not clear to me how best to update this code, so this assert
  70      will alert the first person to encounter the NetBSD/E500
  71      combination to the problem.  */
  72   gdb_assert (ppc_floating_point_unit_p (gdbarch));
  73
  74   return ((regnum >= tdep->ppc_fp0_regnum
  75            && regnum < tdep->ppc_fp0_regnum + ppc_num_fprs)
  76           || regnum == tdep->ppc_fpscr_regnum);
  77 }
  78
  79 static void
  80 ppcnbsd_fetch_inferior_registers (struct target_ops *ops,
  81                                   struct regcache *regcache, int regnum)
  82 {
  83   struct gdbarch *gdbarch = get_regcache_arch (regcache);
  84   pid_t pid = ptid_get_pid (regcache_get_ptid (regcache));
  85
  86   if (regnum == -1 || getregs_supplies (gdbarch, regnum))
  87     {
  88       struct reg regs;
  89
  90       if (ptrace (PT_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
  91         perror_with_name (_("Couldn't get registers"));
  92
  93       ppc_supply_gregset (&ppcnbsd_gregset, regcache,
  94                           regnum, &regs, sizeof regs);
  95     }
  96
  97   if (regnum == -1 || getfpregs_supplies (gdbarch, regnum))
  98     {
  99       struct fpreg fpregs;
 100
 101       if (ptrace (PT_GETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 102         perror_with_name (_("Couldn't get FP registers"));
 103
 104       ppc_supply_fpregset (&ppcnbsd_fpregset, regcache,
 105                            regnum, &fpregs, sizeof fpregs);
 106     }
 107 }
 108
 109 static void
 110 ppcnbsd_store_inferior_registers (struct target_ops *ops,
 111                                   struct regcache *regcache, int regnum)
 112 {
 113   struct gdbarch *gdbarch = get_regcache_arch (regcache);
 114   pid_t pid = ptid_get_pid (regcache_get_ptid (regcache));
 115
 116   if (regnum == -1 || getregs_supplies (gdbarch, regnum))
 117     {
 118       struct reg regs;
 119
 120       if (ptrace (PT_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
 121         perror_with_name (_("Couldn't get registers"));
 122
 123       ppc_collect_gregset (&ppcnbsd_gregset, regcache,
 124                            regnum, &regs, sizeof regs);
 125
 126       if (ptrace (PT_SETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
 127         perror_with_name (_("Couldn't write registers"));
 128     }
 129
 130   if (regnum == -1 || getfpregs_supplies (gdbarch, regnum))
 131     {
 132       struct fpreg fpregs;
 133
 134       if (ptrace (PT_GETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 135         perror_with_name (_("Couldn't get FP registers"));
 136
 137       ppc_collect_fpregset (&ppcnbsd_fpregset, regcache,
 138                             regnum, &fpregs, sizeof fpregs);
 139
 140       if (ptrace (PT_SETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 141         perror_with_name (_("Couldn't set FP registers"));
 142     }
 143 }
 144
 145 static int
 146 ppcnbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
 147 {
 148   struct switchframe sf;
 149   struct callframe cf;
 150   struct gdbarch *gdbarch = get_regcache_arch (regcache);
 151   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 152   int i;
 153
 154   /* The stack pointer shouldn't be zero.  */
 155   if (pcb->pcb_sp == 0)
 156     return 0;
 157
 158   read_memory (pcb->pcb_sp, (gdb_byte *)&sf, sizeof sf);
 159   regcache_raw_supply (regcache, tdep->ppc_cr_regnum, &sf.cr);
 160   regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 2, &sf.fixreg2);
 161   for (i = 0 ; i < 19 ; i++)
 162     regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 13 + i,
 163                          &sf.fixreg[i]);
 164
 165   read_memory(sf.sp, (gdb_byte *)&cf, sizeof(cf));
 166   regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 30, &cf.r30);
 167   regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 31, &cf.r31);
 168   regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 1, &cf.sp);
 169
 170   read_memory(cf.sp, (gdb_byte *)&cf, sizeof(cf));
 171   regcache_raw_supply (regcache, tdep->ppc_lr_regnum, &cf.lr);
 172   regcache_raw_supply (regcache, gdbarch_pc_regnum (gdbarch), &cf.lr);
 173
 174   return 1;
 175 }
 176
 177 void
 178 _initialize_ppcnbsd_nat (void)
 179 {
 180   struct target_ops *t;
 181
 182   /* Support debugging kernel virtual memory images.  */
 183   bsd_kvm_add_target (ppcnbsd_supply_pcb);
 184
 185   /* Add in local overrides.  */
 186   t = inf_ptrace_target ();
 187   t->to_fetch_registers = ppcnbsd_fetch_inferior_registers;
 188   t->to_store_registers = ppcnbsd_store_inferior_registers;
 189   add_target (t);
 190 }