1/* Native-dependent code for OpenBSD/powerpc. 2 3 Copyright (C) 2004, 2005, 2006, 2007 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 47static int 48getfpregs_supplies (int regnum) 49{ 50 struct gdbarch_tdep *tdep = gdbarch_tdep (current_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 (current_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 74static void 75ppcobsd_fetch_registers (struct regcache *regcache, int regnum) 76{ 77 struct reg regs; 78 79 if (ptrace (PT_GETREGS, PIDGET (inferior_ptid), 80 (PTRACE_TYPE_ARG3) ®s, 0) == -1) 81 perror_with_name (_("Couldn't get registers")); 82 83 ppc_supply_gregset (&ppcobsd_gregset, regcache, -1, 84 ®s, sizeof regs); 85#ifndef PT_GETFPREGS 86 ppc_supply_fpregset (&ppcobsd_gregset, regcache, -1, 87 ®s, sizeof regs); 88#endif 89 90#ifdef PT_GETFPREGS 91 if (regnum == -1 || getfpregs_supplies (regnum)) 92 { 93 struct fpreg fpregs; 94 95 if (ptrace (PT_GETFPREGS, PIDGET (inferior_ptid), 96 (PTRACE_TYPE_ARG3) &fpregs, 0) == -1) 97 perror_with_name (_("Couldn't get floating point status")); 98 99 ppc_supply_fpregset (&ppcobsd_fpregset, regcache, -1, 100 &fpregs, sizeof fpregs); 101 } 102#endif 103} 104 105/* Store register REGNUM back into the inferior. If REGNUM is -1, do 106 this for all registers. */ 107 108static void 109ppcobsd_store_registers (struct regcache *regcache, int regnum) 110{ 111 struct reg regs; 112 113 if (ptrace (PT_GETREGS, PIDGET (inferior_ptid), 114 (PTRACE_TYPE_ARG3) ®s, 0) == -1) 115 perror_with_name (_("Couldn't get registers")); 116 117 ppc_collect_gregset (&ppcobsd_gregset, regcache, 118 regnum, ®s, sizeof regs); 119#ifndef PT_GETFPREGS 120 ppc_collect_fpregset (&ppcobsd_gregset, regcache, 121 regnum, ®s, sizeof regs); 122#endif 123 124 if (ptrace (PT_SETREGS, PIDGET (inferior_ptid), 125 (PTRACE_TYPE_ARG3) ®s, 0) == -1) 126 perror_with_name (_("Couldn't write registers")); 127 128#ifdef PT_GETFPREGS 129 if (regnum == -1 || getfpregs_supplies (regnum)) 130 { 131 struct fpreg fpregs; 132 133 if (ptrace (PT_GETFPREGS, PIDGET (inferior_ptid), 134 (PTRACE_TYPE_ARG3) &fpregs, 0) == -1) 135 perror_with_name (_("Couldn't get floating point status")); 136 137 ppc_collect_fpregset (&ppcobsd_fpregset, regcache, 138 regnum, &fpregs, sizeof fpregs); 139 140 if (ptrace (PT_SETFPREGS, PIDGET (inferior_ptid), 141 (PTRACE_TYPE_ARG3) &fpregs, 0) == -1) 142 perror_with_name (_("Couldn't write floating point status")); 143 } 144#endif 145} 146 147 148static int 149ppcobsd_supply_pcb (struct regcache *regcache, struct pcb *pcb) 150{ 151 struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (regcache)); 152 struct switchframe sf; 153 struct callframe cf; 154 int i, regnum; 155 156 /* The following is true for OpenBSD 3.7: 157 158 The pcb contains %r1 (the stack pointer) at the point of the 159 context switch in cpu_switch(). At that point we have a stack 160 frame as described by `struct switchframe', and below that a call 161 frame as described by `struct callframe'. From this information 162 we reconstruct the register state as it would look when we are in 163 cpu_switch(). */ 164 165 /* The stack pointer shouldn't be zero. */ 166 if (pcb->pcb_sp == 0) 167 return 0; 168 169 read_memory (pcb->pcb_sp, (gdb_byte *)&sf, sizeof sf); 170 regcache_raw_supply (regcache, gdbarch_sp_regnum (current_gdbarch), &sf.sp); 171 regcache_raw_supply (regcache, tdep->ppc_cr_regnum, &sf.cr); 172 regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 2, &sf.fixreg2); 173 for (i = 0, regnum = tdep->ppc_gp0_regnum + 13; i < 19; i++, regnum++) 174 regcache_raw_supply (regcache, regnum, &sf.fixreg[i]); 175 176 read_memory (sf.sp, (gdb_byte *)&cf, sizeof cf); 177 regcache_raw_supply (regcache, gdbarch_pc_regnum (current_gdbarch), &cf.lr); 178 regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 30, &cf.r30); 179 regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 31, &cf.r31); 180 181 return 1; 182} 183 184 185/* Provide a prototype to silence -Wmissing-prototypes. */ 186void _initialize_ppcobsd_nat (void); 187 188void 189_initialize_ppcobsd_nat (void) 190{ 191 struct target_ops *t; 192 193 /* Add in local overrides. */ 194 t = inf_ptrace_target (); 195 t->to_fetch_registers = ppcobsd_fetch_registers; 196 t->to_store_registers = ppcobsd_store_registers; 197 add_target (t); 198 199 /* General-purpose registers. */ 200 ppcobsd_reg_offsets.r0_offset = offsetof (struct reg, gpr); 201 ppcobsd_reg_offsets.gpr_size = 4; 202 ppcobsd_reg_offsets.xr_size = 4; 203 ppcobsd_reg_offsets.pc_offset = offsetof (struct reg, pc); 204 ppcobsd_reg_offsets.ps_offset = offsetof (struct reg, ps); 205 ppcobsd_reg_offsets.cr_offset = offsetof (struct reg, cnd); 206 ppcobsd_reg_offsets.lr_offset = offsetof (struct reg, lr); 207 ppcobsd_reg_offsets.ctr_offset = offsetof (struct reg, cnt); 208 ppcobsd_reg_offsets.xer_offset = offsetof (struct reg, xer); 209 ppcobsd_reg_offsets.mq_offset = offsetof (struct reg, mq); 210 211 /* Floating-point registers. */ 212 ppcobsd_reg_offsets.f0_offset = offsetof (struct reg, fpr); 213 ppcobsd_reg_offsets.fpscr_offset = -1; 214#ifdef PT_GETFPREGS 215 ppcobsd_fpreg_offsets.f0_offset = offsetof (struct fpreg, fpr); 216 ppcobsd_fpreg_offsets.fpscr_offset = offsetof (struct fpreg, fpscr); 217 ppcobsd_fpreg_offsets.fpscr_size = 4; 218#endif 219 220 /* AltiVec registers. */ 221 ppcobsd_reg_offsets.vr0_offset = offsetof (struct vreg, vreg); 222 ppcobsd_reg_offsets.vscr_offset = offsetof (struct vreg, vscr); 223 ppcobsd_reg_offsets.vrsave_offset = offsetof (struct vreg, vrsave); 224 225 /* Support debugging kernel virtual memory images. */ 226 bsd_kvm_add_target (ppcobsd_supply_pcb); 227} 228