xref: /netbsd-src/external/gpl3/gdb/dist/gdb/riscv-netbsd-nat.c (revision 26ff2d23d52ec7cccb99764698504f64357c54d3)
1 /* Native-dependent code for NetBSD/riscv.
2 
3    Copyright (C) 2018-2020 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 "regcache.h"
22 #include "target.h"
23 
24 #include <sys/types.h>
25 #include <sys/ptrace.h>
26 #include <machine/reg.h>
27 
28 #include "netbsd-nat.h"
29 #include "riscv-tdep.h"
30 #include "riscv-netbsd-tdep.h"
31 #include "inf-ptrace.h"
32 
33 struct riscv_nbsd_nat_target final : public nbsd_nat_target
34 {
35   void fetch_registers (struct regcache *, int) override;
36   void store_registers (struct regcache *, int) override;
37 };
38 
39 static riscv_nbsd_nat_target the_riscv_nbsd_nat_target;
40 
41 /* Determine if PT_GETREGS fetches REGNUM.  */
42 
43 static bool
getregs_supplies(int regnum)44 getregs_supplies (int regnum)
45 {
46   return regnum >= RISCV_RA_REGNUM && regnum <= RISCV_PC_REGNUM;
47 }
48 
49 /* Determine if PT_GETFPREGS fetches REGNUM.  */
50 
51 static bool
getfpregs_supplies(int regnum)52 getfpregs_supplies (int regnum)
53 {
54   return ((regnum >= RISCV_FIRST_FP_REGNUM && regnum <= RISCV_LAST_FP_REGNUM)
55 	  || regnum == RISCV_CSR_FCSR_REGNUM);
56 }
57 
58 /* Fetch register REGNUM from the inferior.  If REGNUM is -1, do this
59    for all registers.  */
60 
61 void
fetch_registers(struct regcache * regcache,int regnum)62 riscv_nbsd_nat_target::fetch_registers (struct regcache *regcache,
63 					int regnum)
64 {
65   pid_t pid = regcache->ptid ().pid ();
66   int lwp = regcache->ptid ().lwp ();
67 
68   if (regnum == -1 || regnum == RISCV_ZERO_REGNUM)
69     regcache->raw_supply_zeroed (RISCV_ZERO_REGNUM);
70   if (regnum == -1 || getregs_supplies (regnum))
71     {
72       struct reg regs;
73 
74       if (ptrace (PT_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, lwp) == -1)
75 	perror_with_name (_("Couldn't get registers"));
76 
77       regcache->supply_regset (&riscv_nbsd_gregset, regnum, &regs,
78 			       sizeof (regs));
79     }
80 
81   if (regnum == -1 || getfpregs_supplies (regnum))
82     {
83       struct fpreg fpregs;
84 
85       if (ptrace (PT_GETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
86 	perror_with_name (_("Couldn't get floating point status"));
87 
88       regcache->supply_regset (&riscv_nbsd_fpregset, regnum, &fpregs,
89 			       sizeof (fpregs));
90     }
91 }
92 
93 /* Store register REGNUM back into the inferior.  If REGNUM is -1, do
94    this for all registers.  */
95 
96 void
store_registers(struct regcache * regcache,int regnum)97 riscv_nbsd_nat_target::store_registers (struct regcache *regcache,
98 					int regnum)
99 {
100   pid_t pid = regcache->ptid ().pid ();
101   int lwp = regcache->ptid ().lwp ();
102 
103   if (regnum == -1 || getregs_supplies (regnum))
104     {
105       struct reg regs;
106 
107       if (ptrace (PT_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, lwp) == -1)
108 	perror_with_name (_("Couldn't get registers"));
109 
110       regcache->collect_regset (&riscv_nbsd_gregset, regnum, &regs,
111 			       sizeof (regs));
112 
113       if (ptrace (PT_SETREGS, pid, (PTRACE_TYPE_ARG3) &regs, lwp) == -1)
114 	perror_with_name (_("Couldn't write registers"));
115     }
116 
117   if (regnum == -1 || getfpregs_supplies (regnum))
118     {
119       struct fpreg fpregs;
120 
121       if (ptrace (PT_GETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, lwp) == -1)
122 	perror_with_name (_("Couldn't get floating point status"));
123 
124       regcache->collect_regset (&riscv_nbsd_fpregset, regnum, &fpregs,
125 				sizeof (fpregs));
126 
127       if (ptrace (PT_SETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, lwp) == -1)
128 	perror_with_name (_("Couldn't write floating point status"));
129     }
130 }
131 
132 /* Initialize RISC-V NetBSD native support.  */
133 
134 void _initialize_riscv_nbsd_nat ();
135 void
_initialize_riscv_nbsd_nat()136 _initialize_riscv_nbsd_nat ()
137 {
138   add_inf_child_target (&the_riscv_nbsd_nat_target);
139 
140 //  bsd_kvm_add_target (riscv_nbsd_supply_pcb);
141 }
142