gdb/bfin-linux-tdep.c

   1 /* Target-dependent code for Analog Devices Blackfin processor, for GDB.
   2
   3    Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010
   4    Free Software Foundation, Inc.
   5
   6    Contributed by Analog Devices, Inc.
   7
   8    This file is part of GDB.
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 3 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  22
  23 #include "defs.h"
  24 #include "arch-utils.h"
  25 #include "regcache.h"
  26 #include "tramp-frame.h"
  27 #include "trad-frame.h"
  28 #include "osabi.h"
  29 #include "xml-syscall.h"
  30 #include "linux-tdep.h"
  31 #include "bfin-tdep.h"
  32
  33 /* From <asm/sigcontext.h>.  */
  34
  35 #define SIGCONTEXT_OFFSET       168
  36
  37 static const int bfin_linux_sigcontext_reg_offset[BFIN_NUM_REGS] =
  38 {
  39   0 * 4,        /* %r0 */
  40   1 * 4,        /* %r1 */
  41   2 * 4,        /* %r2 */
  42   3 * 4,        /* %r3 */
  43   4 * 4,        /* %r4 */
  44   5 * 4,        /* %r5 */
  45   6 * 4,        /* %r6 */
  46   7 * 4,        /* %r7 */
  47   8 * 4,        /* %p0 */
  48   9 * 4,        /* %p1 */
  49   10 * 4,       /* %p2 */
  50   11 * 4,       /* %p3 */
  51   12 * 4,       /* %p4 */
  52   13 * 4,       /* %p5 */
  53   14 * 4,       /* %sp */
  54   23 * 4,       /* %fp */
  55   24 * 4,       /* %i0 */
  56   25 * 4,       /* %i1 */
  57   26 * 4,       /* %i2 */
  58   27 * 4,       /* %i3 */
  59   28 * 4,       /* %m0 */
  60   29 * 4,       /* %m1 */
  61   30 * 4,       /* %m2 */
  62   31 * 4,       /* %m3 */
  63   36 * 4,       /* %b0 */
  64   37 * 4,       /* %b1 */
  65   38 * 4,       /* %b2 */
  66   39 * 4,       /* %b3 */
  67   32 * 4,       /* %l0 */
  68   33 * 4,       /* %l1 */
  69   34 * 4,       /* %l2 */
  70   35 * 4,       /* %l3 */
  71   17 * 4,       /* %a0x */
  72   15 * 4,       /* %a0w */
  73   18 * 4,       /* %a1x */
  74   16 * 4,       /* %a1w */
  75   19 * 4,       /* %astat */
  76   20 * 4,       /* %rets */
  77   40 * 4,       /* %lc0 */
  78   42 * 4,       /* %lt0 */
  79   44 * 4,       /* %lb0 */
  80   41 * 4,       /* %lc1 */
  81   43 * 4,       /* %lt1 */
  82   45 * 4,       /* %lb1 */
  83   -1,           /* %cycles */
  84   -1,           /* %cycles2 */
  85   -1,           /* %usp */
  86   46 * 4,       /* %seqstat */
  87   -1,           /* syscfg */
  88   21 * 4,       /* %reti */
  89   22 * 4,       /* %retx */
  90   -1,           /* %retn */
  91   -1,           /* %rete */
  92   21 * 4,       /* %pc */
  93 };
  94
  95 /* Signal trampolines.  */
  96
  97 static void
  98 bfin_linux_sigframe_init (const struct tramp_frame *self,
  99                           struct frame_info *this_frame,
 100                           struct trad_frame_cache *this_cache,
 101                           CORE_ADDR func)
 102 {
 103   struct gdbarch *gdbarch = get_frame_arch (this_frame);
 104   CORE_ADDR sp = get_frame_sp (this_frame);
 105   CORE_ADDR pc = get_frame_pc (this_frame);
 106   CORE_ADDR sigcontext = sp + SIGCONTEXT_OFFSET;
 107   struct frame_id this_id;
 108   const int *reg_offset = bfin_linux_sigcontext_reg_offset;
 109   int i;
 110
 111   for (i = 0; i < BFIN_NUM_REGS; i++)
 112     if (reg_offset[i] != -1)
 113       trad_frame_set_reg_addr (this_cache, i, sigcontext + reg_offset[i]);
 114
 115   /* This would come after the LINK instruction in the ret_from_signal
 116      function, hence the frame id would be SP + 8.  */
 117   trad_frame_set_id (this_cache, frame_id_build (sp + 8, pc));
 118 }
 119
 120 static const struct tramp_frame bfin_linux_sigframe =
 121 {
 122   SIGTRAMP_FRAME,
 123   4,
 124   {
 125     { 0x00ADE128, 0xffffffff }, /* P0 = __NR_rt_sigreturn; */
 126     { 0x00A0, 0xffff },         /* EXCPT 0; */
 127     { TRAMP_SENTINEL_INSN, -1 },
 128   },
 129   bfin_linux_sigframe_init,
 130 };
 131
 132 static LONGEST
 133 bfin_linux_get_syscall_number (struct gdbarch *gdbarch,
 134                                ptid_t ptid)
 135 {
 136   struct regcache *regcache = get_thread_regcache (ptid);
 137   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
 138   /* The content of a register.  */
 139   gdb_byte buf[4];
 140   /* The result.  */
 141   LONGEST ret;
 142
 143   /* Getting the system call number from the register.
 144      When dealing with Blackfin architecture, this information
 145      is stored at %p0 register.  */
 146   regcache_cooked_read (regcache, BFIN_P0_REGNUM, buf);
 147
 148   ret = extract_signed_integer (buf, 4, byte_order);
 149
 150   return ret;
 151 }
 152
 153 static void
 154 bfin_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 155 {
 156   linux_init_abi (info, gdbarch);
 157
 158   /* Set the sigtramp frame sniffer.  */
 159   tramp_frame_prepend_unwinder (gdbarch, &bfin_linux_sigframe);
 160
 161   /* Functions for 'catch syscall'.  */
 162   set_xml_syscall_file_name ("syscalls/bfin-linux.xml");
 163   set_gdbarch_get_syscall_number (gdbarch,
 164                                   bfin_linux_get_syscall_number);
 165 }
 166
 167 /* Provide a prototype to silence -Wmissing-prototypes.  */
 168 extern initialize_file_ftype _initialize_bfin_linux_tdep;
 169
 170 void
 171 _initialize_bfin_linux_tdep (void)
 172 {
 173   gdbarch_register_osabi (bfd_arch_bfin, 0, GDB_OSABI_LINUX,
 174                           bfin_linux_init_abi);
 175 }