| 1 | /* Native-dependent code for OpenBSD/powerpc. |
| 2 | |
| 3 | Copyright (C) 2004-2014 Free Software Foundation, Inc. |
| 4 | |
| 5 | This file is part of GDB. |
| 6 | |
| 7 | This program is free software; you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation; either version 3 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 19 | |
| 20 | #include "defs.h" |
| 21 | #include "gdbcore.h" |
| 22 | #include "inferior.h" |
| 23 | #include "regcache.h" |
| 24 | |
| 25 | #include "gdb_assert.h" |
| 26 | #include <stddef.h> |
| 27 | #include <sys/types.h> |
| 28 | #include <sys/ptrace.h> |
| 29 | #include <sys/signal.h> |
| 30 | #include <machine/frame.h> |
| 31 | #include <machine/pcb.h> |
| 32 | #include <machine/reg.h> |
| 33 | |
| 34 | #include "ppc-tdep.h" |
| 35 | #include "ppcobsd-tdep.h" |
| 36 | #include "inf-ptrace.h" |
| 37 | #include "bsd-kvm.h" |
| 38 | |
| 39 | /* OpenBSD/powerpc didn't have PT_GETFPREGS/PT_SETFPREGS until release |
| 40 | 4.0. On older releases the floating-point registers are handled by |
| 41 | PT_GETREGS/PT_SETREGS, but fpscr wasn't available.. */ |
| 42 | |
| 43 | #ifdef PT_GETFPREGS |
| 44 | |
| 45 | /* Returns true if PT_GETFPREGS fetches this register. */ |
| 46 | |
| 47 | static int |
| 48 | getfpregs_supplies (struct gdbarch *gdbarch, int regnum) |
| 49 | { |
| 50 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 51 | |
| 52 | /* FIXME: jimb/2004-05-05: Some PPC variants don't have floating |
| 53 | point registers. Traditionally, GDB's register set has still |
| 54 | listed the floating point registers for such machines, so this |
| 55 | code is harmless. However, the new E500 port actually omits the |
| 56 | floating point registers entirely from the register set --- they |
| 57 | don't even have register numbers assigned to them. |
| 58 | |
| 59 | It's not clear to me how best to update this code, so this assert |
| 60 | will alert the first person to encounter the NetBSD/E500 |
| 61 | combination to the problem. */ |
| 62 | gdb_assert (ppc_floating_point_unit_p (gdbarch)); |
| 63 | |
| 64 | return ((regnum >= tdep->ppc_fp0_regnum |
| 65 | && regnum < tdep->ppc_fp0_regnum + ppc_num_fprs) |
| 66 | || regnum == tdep->ppc_fpscr_regnum); |
| 67 | } |
| 68 | |
| 69 | #endif /* PT_GETFPREGS */ |
| 70 | |
| 71 | /* Fetch register REGNUM from the inferior. If REGNUM is -1, do this |
| 72 | for all registers. */ |
| 73 | |
| 74 | static void |
| 75 | ppcobsd_fetch_registers (struct target_ops *ops, |
| 76 | struct regcache *regcache, int regnum) |
| 77 | { |
| 78 | struct reg regs; |
| 79 | |
| 80 | if (ptrace (PT_GETREGS, ptid_get_pid (inferior_ptid), |
| 81 | (PTRACE_TYPE_ARG3) ®s, 0) == -1) |
| 82 | perror_with_name (_("Couldn't get registers")); |
| 83 | |
| 84 | ppc_supply_gregset (&ppcobsd_gregset, regcache, -1, |
| 85 | ®s, sizeof regs); |
| 86 | #ifndef PT_GETFPREGS |
| 87 | ppc_supply_fpregset (&ppcobsd_gregset, regcache, -1, |
| 88 | ®s, sizeof regs); |
| 89 | #endif |
| 90 | |
| 91 | #ifdef PT_GETFPREGS |
| 92 | if (regnum == -1 |
| 93 | || getfpregs_supplies (get_regcache_arch (regcache), regnum)) |
| 94 | { |
| 95 | struct fpreg fpregs; |
| 96 | |
| 97 | if (ptrace (PT_GETFPREGS, ptid_get_pid (inferior_ptid), |
| 98 | (PTRACE_TYPE_ARG3) &fpregs, 0) == -1) |
| 99 | perror_with_name (_("Couldn't get floating point status")); |
| 100 | |
| 101 | ppc_supply_fpregset (&ppcobsd_fpregset, regcache, -1, |
| 102 | &fpregs, sizeof fpregs); |
| 103 | } |
| 104 | #endif |
| 105 | } |
| 106 | |
| 107 | /* Store register REGNUM back into the inferior. If REGNUM is -1, do |
| 108 | this for all registers. */ |
| 109 | |
| 110 | static void |
| 111 | ppcobsd_store_registers (struct target_ops *ops, |
| 112 | struct regcache *regcache, int regnum) |
| 113 | { |
| 114 | struct reg regs; |
| 115 | |
| 116 | if (ptrace (PT_GETREGS, ptid_get_pid (inferior_ptid), |
| 117 | (PTRACE_TYPE_ARG3) ®s, 0) == -1) |
| 118 | perror_with_name (_("Couldn't get registers")); |
| 119 | |
| 120 | ppc_collect_gregset (&ppcobsd_gregset, regcache, |
| 121 | regnum, ®s, sizeof regs); |
| 122 | #ifndef PT_GETFPREGS |
| 123 | ppc_collect_fpregset (&ppcobsd_gregset, regcache, |
| 124 | regnum, ®s, sizeof regs); |
| 125 | #endif |
| 126 | |
| 127 | if (ptrace (PT_SETREGS, ptid_get_pid (inferior_ptid), |
| 128 | (PTRACE_TYPE_ARG3) ®s, 0) == -1) |
| 129 | perror_with_name (_("Couldn't write registers")); |
| 130 | |
| 131 | #ifdef PT_GETFPREGS |
| 132 | if (regnum == -1 |
| 133 | || getfpregs_supplies (get_regcache_arch (regcache), regnum)) |
| 134 | { |
| 135 | struct fpreg fpregs; |
| 136 | |
| 137 | if (ptrace (PT_GETFPREGS, ptid_get_pid (inferior_ptid), |
| 138 | (PTRACE_TYPE_ARG3) &fpregs, 0) == -1) |
| 139 | perror_with_name (_("Couldn't get floating point status")); |
| 140 | |
| 141 | ppc_collect_fpregset (&ppcobsd_fpregset, regcache, |
| 142 | regnum, &fpregs, sizeof fpregs); |
| 143 | |
| 144 | if (ptrace (PT_SETFPREGS, ptid_get_pid (inferior_ptid), |
| 145 | (PTRACE_TYPE_ARG3) &fpregs, 0) == -1) |
| 146 | perror_with_name (_("Couldn't write floating point status")); |
| 147 | } |
| 148 | #endif |
| 149 | } |
| 150 | \f |
| 151 | |
| 152 | static int |
| 153 | ppcobsd_supply_pcb (struct regcache *regcache, struct pcb *pcb) |
| 154 | { |
| 155 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
| 156 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 157 | struct switchframe sf; |
| 158 | struct callframe cf; |
| 159 | int i, regnum; |
| 160 | |
| 161 | /* The following is true for OpenBSD 3.7: |
| 162 | |
| 163 | The pcb contains %r1 (the stack pointer) at the point of the |
| 164 | context switch in cpu_switch(). At that point we have a stack |
| 165 | frame as described by `struct switchframe', and below that a call |
| 166 | frame as described by `struct callframe'. From this information |
| 167 | we reconstruct the register state as it would look when we are in |
| 168 | cpu_switch(). */ |
| 169 | |
| 170 | /* The stack pointer shouldn't be zero. */ |
| 171 | if (pcb->pcb_sp == 0) |
| 172 | return 0; |
| 173 | |
| 174 | read_memory (pcb->pcb_sp, (gdb_byte *)&sf, sizeof sf); |
| 175 | regcache_raw_supply (regcache, gdbarch_sp_regnum (gdbarch), &sf.sp); |
| 176 | regcache_raw_supply (regcache, tdep->ppc_cr_regnum, &sf.cr); |
| 177 | regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 2, &sf.fixreg2); |
| 178 | for (i = 0, regnum = tdep->ppc_gp0_regnum + 13; i < 19; i++, regnum++) |
| 179 | regcache_raw_supply (regcache, regnum, &sf.fixreg[i]); |
| 180 | |
| 181 | read_memory (sf.sp, (gdb_byte *)&cf, sizeof cf); |
| 182 | regcache_raw_supply (regcache, gdbarch_pc_regnum (gdbarch), &cf.lr); |
| 183 | regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 30, &cf.r30); |
| 184 | regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 31, &cf.r31); |
| 185 | |
| 186 | return 1; |
| 187 | } |
| 188 | \f |
| 189 | |
| 190 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
| 191 | void _initialize_ppcobsd_nat (void); |
| 192 | |
| 193 | void |
| 194 | _initialize_ppcobsd_nat (void) |
| 195 | { |
| 196 | struct target_ops *t; |
| 197 | |
| 198 | /* Add in local overrides. */ |
| 199 | t = inf_ptrace_target (); |
| 200 | t->to_fetch_registers = ppcobsd_fetch_registers; |
| 201 | t->to_store_registers = ppcobsd_store_registers; |
| 202 | add_target (t); |
| 203 | |
| 204 | /* General-purpose registers. */ |
| 205 | ppcobsd_reg_offsets.r0_offset = offsetof (struct reg, gpr); |
| 206 | ppcobsd_reg_offsets.gpr_size = 4; |
| 207 | ppcobsd_reg_offsets.xr_size = 4; |
| 208 | ppcobsd_reg_offsets.pc_offset = offsetof (struct reg, pc); |
| 209 | ppcobsd_reg_offsets.ps_offset = offsetof (struct reg, ps); |
| 210 | ppcobsd_reg_offsets.cr_offset = offsetof (struct reg, cnd); |
| 211 | ppcobsd_reg_offsets.lr_offset = offsetof (struct reg, lr); |
| 212 | ppcobsd_reg_offsets.ctr_offset = offsetof (struct reg, cnt); |
| 213 | ppcobsd_reg_offsets.xer_offset = offsetof (struct reg, xer); |
| 214 | ppcobsd_reg_offsets.mq_offset = offsetof (struct reg, mq); |
| 215 | |
| 216 | /* Floating-point registers. */ |
| 217 | ppcobsd_reg_offsets.f0_offset = offsetof (struct reg, fpr); |
| 218 | ppcobsd_reg_offsets.fpscr_offset = -1; |
| 219 | #ifdef PT_GETFPREGS |
| 220 | ppcobsd_fpreg_offsets.f0_offset = offsetof (struct fpreg, fpr); |
| 221 | ppcobsd_fpreg_offsets.fpscr_offset = offsetof (struct fpreg, fpscr); |
| 222 | ppcobsd_fpreg_offsets.fpscr_size = 4; |
| 223 | #endif |
| 224 | |
| 225 | /* AltiVec registers. */ |
| 226 | ppcobsd_reg_offsets.vr0_offset = offsetof (struct vreg, vreg); |
| 227 | ppcobsd_reg_offsets.vscr_offset = offsetof (struct vreg, vscr); |
| 228 | ppcobsd_reg_offsets.vrsave_offset = offsetof (struct vreg, vrsave); |
| 229 | |
| 230 | /* Support debugging kernel virtual memory images. */ |
| 231 | bsd_kvm_add_target (ppcobsd_supply_pcb); |
| 232 | } |