1 /* Native-dependent code for OpenBSD/powerpc.
3 Copyright (C) 2004-2018 Free Software Foundation, Inc.
5 This file is part of GDB.
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.
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.
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/>. */
25 #include <sys/types.h>
26 #include <sys/ptrace.h>
27 #include <sys/signal.h>
28 #include <machine/frame.h>
29 #include <machine/pcb.h>
30 #include <machine/reg.h>
33 #include "ppc-obsd-tdep.h"
34 #include "inf-ptrace.h"
38 struct ppc_obsd_nat_target final : public obsd_nat_target
40 void fetch_registers (struct regcache *, int) override;
41 void store_registers (struct regcache *, int) override;
44 static ppc_obsd_nat_target the_ppc_obsd_nat_target;
46 /* OpenBSD/powerpc didn't have PT_GETFPREGS/PT_SETFPREGS until release
47 4.0. On older releases the floating-point registers are handled by
48 PT_GETREGS/PT_SETREGS, but fpscr wasn't available.. */
52 /* Returns true if PT_GETFPREGS fetches this register. */
55 getfpregs_supplies (struct gdbarch *gdbarch, int regnum)
57 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
59 /* FIXME: jimb/2004-05-05: Some PPC variants don't have floating
60 point registers. Traditionally, GDB's register set has still
61 listed the floating point registers for such machines, so this
62 code is harmless. However, the new E500 port actually omits the
63 floating point registers entirely from the register set --- they
64 don't even have register numbers assigned to them.
66 It's not clear to me how best to update this code, so this assert
67 will alert the first person to encounter the NetBSD/E500
68 combination to the problem. */
69 gdb_assert (ppc_floating_point_unit_p (gdbarch));
71 return ((regnum >= tdep->ppc_fp0_regnum
72 && regnum < tdep->ppc_fp0_regnum + ppc_num_fprs)
73 || regnum == tdep->ppc_fpscr_regnum);
76 #endif /* PT_GETFPREGS */
78 /* Fetch register REGNUM from the inferior. If REGNUM is -1, do this
82 ppc_obsd_nat_target::fetch_registers (struct regcache *regcache, int regnum)
85 pid_t pid = ptid_get_pid (regcache->ptid ());
87 if (ptrace (PT_GETREGS, pid, (PTRACE_TYPE_ARG3) ®s, 0) == -1)
88 perror_with_name (_("Couldn't get registers"));
90 ppc_supply_gregset (&ppcobsd_gregset, regcache, -1,
93 ppc_supply_fpregset (&ppcobsd_gregset, regcache, -1,
99 || getfpregs_supplies (regcache->arch (), regnum))
103 if (ptrace (PT_GETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
104 perror_with_name (_("Couldn't get floating point status"));
106 ppc_supply_fpregset (&ppcobsd_fpregset, regcache, -1,
107 &fpregs, sizeof fpregs);
112 /* Store register REGNUM back into the inferior. If REGNUM is -1, do
113 this for all registers. */
116 ppc_obsd_nat_target::store_registers (struct regcache *regcache, int regnum)
119 pid_t pid = ptid_get_pid (regcache->ptid ());
121 if (ptrace (PT_GETREGS, pid, (PTRACE_TYPE_ARG3) ®s, 0) == -1)
122 perror_with_name (_("Couldn't get registers"));
124 ppc_collect_gregset (&ppcobsd_gregset, regcache,
125 regnum, ®s, sizeof regs);
127 ppc_collect_fpregset (&ppcobsd_gregset, regcache,
128 regnum, ®s, sizeof regs);
131 if (ptrace (PT_SETREGS, pid, (PTRACE_TYPE_ARG3) ®s, 0) == -1)
132 perror_with_name (_("Couldn't write registers"));
136 || getfpregs_supplies (regcache->arch (), regnum))
140 if (ptrace (PT_GETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
141 perror_with_name (_("Couldn't get floating point status"));
143 ppc_collect_fpregset (&ppcobsd_fpregset, regcache,
144 regnum, &fpregs, sizeof fpregs);
146 if (ptrace (PT_SETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
147 perror_with_name (_("Couldn't write floating point status"));
154 ppcobsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
156 struct gdbarch *gdbarch = regcache->arch ();
157 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
158 struct switchframe sf;
162 /* The following is true for OpenBSD 3.7:
164 The pcb contains %r1 (the stack pointer) at the point of the
165 context switch in cpu_switch(). At that point we have a stack
166 frame as described by `struct switchframe', and below that a call
167 frame as described by `struct callframe'. From this information
168 we reconstruct the register state as it would look when we are in
171 /* The stack pointer shouldn't be zero. */
172 if (pcb->pcb_sp == 0)
175 read_memory (pcb->pcb_sp, (gdb_byte *)&sf, sizeof sf);
176 regcache_raw_supply (regcache, gdbarch_sp_regnum (gdbarch), &sf.sp);
177 regcache_raw_supply (regcache, tdep->ppc_cr_regnum, &sf.cr);
178 regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 2, &sf.fixreg2);
179 for (i = 0, regnum = tdep->ppc_gp0_regnum + 13; i < 19; i++, regnum++)
180 regcache_raw_supply (regcache, regnum, &sf.fixreg[i]);
182 read_memory (sf.sp, (gdb_byte *)&cf, sizeof cf);
183 regcache_raw_supply (regcache, gdbarch_pc_regnum (gdbarch), &cf.lr);
184 regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 30, &cf.r30);
185 regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 31, &cf.r31);
191 _initialize_ppcobsd_nat (void)
193 add_inf_child_target (&the_ppc_obsd_nat_target);
195 /* General-purpose registers. */
196 ppcobsd_reg_offsets.r0_offset = offsetof (struct reg, gpr);
197 ppcobsd_reg_offsets.gpr_size = 4;
198 ppcobsd_reg_offsets.xr_size = 4;
199 ppcobsd_reg_offsets.pc_offset = offsetof (struct reg, pc);
200 ppcobsd_reg_offsets.ps_offset = offsetof (struct reg, ps);
201 ppcobsd_reg_offsets.cr_offset = offsetof (struct reg, cnd);
202 ppcobsd_reg_offsets.lr_offset = offsetof (struct reg, lr);
203 ppcobsd_reg_offsets.ctr_offset = offsetof (struct reg, cnt);
204 ppcobsd_reg_offsets.xer_offset = offsetof (struct reg, xer);
205 ppcobsd_reg_offsets.mq_offset = offsetof (struct reg, mq);
207 /* Floating-point registers. */
208 ppcobsd_reg_offsets.f0_offset = offsetof (struct reg, fpr);
209 ppcobsd_reg_offsets.fpscr_offset = -1;
211 ppcobsd_fpreg_offsets.f0_offset = offsetof (struct fpreg, fpr);
212 ppcobsd_fpreg_offsets.fpscr_offset = offsetof (struct fpreg, fpscr);
213 ppcobsd_fpreg_offsets.fpscr_size = 4;
216 /* Support debugging kernel virtual memory images. */
217 bsd_kvm_add_target (ppcobsd_supply_pcb);