| /* GNU/Linux/ARM specific low level interface, for the remote server for GDB. |
| Copyright (C) 1995, 1996, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, |
| 2006, 2007, 2008, 2009 Free Software Foundation, Inc. |
| |
| This file is part of GDB. |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 3 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| |
| #include "server.h" |
| #include "linux-low.h" |
| |
| #include <elf.h> |
| #include <sys/ptrace.h> |
| |
| #include "gdb_proc_service.h" |
| |
| /* Defined in auto-generated files. */ |
| void init_registers_arm (void); |
| void init_registers_arm_with_iwmmxt (void); |
| void init_registers_arm_with_vfpv2 (void); |
| void init_registers_arm_with_vfpv3 (void); |
| void init_registers_arm_with_neon (void); |
| |
| #ifndef PTRACE_GET_THREAD_AREA |
| #define PTRACE_GET_THREAD_AREA 22 |
| #endif |
| |
| #ifndef PTRACE_GETWMMXREGS |
| # define PTRACE_GETWMMXREGS 18 |
| # define PTRACE_SETWMMXREGS 19 |
| #endif |
| |
| #ifndef PTRACE_GETVFPREGS |
| # define PTRACE_GETVFPREGS 27 |
| # define PTRACE_SETVFPREGS 28 |
| #endif |
| |
| static unsigned long arm_hwcap; |
| |
| /* These are in <asm/elf.h> in current kernels. */ |
| #define HWCAP_VFP 64 |
| #define HWCAP_IWMMXT 512 |
| #define HWCAP_NEON 4096 |
| #define HWCAP_VFPv3 8192 |
| #define HWCAP_VFPv3D16 16384 |
| |
| #ifdef HAVE_SYS_REG_H |
| #include <sys/reg.h> |
| #endif |
| |
| #define arm_num_regs 26 |
| |
| static int arm_regmap[] = { |
| 0, 4, 8, 12, 16, 20, 24, 28, |
| 32, 36, 40, 44, 48, 52, 56, 60, |
| -1, -1, -1, -1, -1, -1, -1, -1, -1, |
| 64 |
| }; |
| |
| static int |
| arm_cannot_store_register (int regno) |
| { |
| return (regno >= arm_num_regs); |
| } |
| |
| static int |
| arm_cannot_fetch_register (int regno) |
| { |
| return (regno >= arm_num_regs); |
| } |
| |
| static void |
| arm_fill_gregset (void *buf) |
| { |
| int i; |
| |
| for (i = 0; i < arm_num_regs; i++) |
| if (arm_regmap[i] != -1) |
| collect_register (i, ((char *) buf) + arm_regmap[i]); |
| } |
| |
| static void |
| arm_store_gregset (const void *buf) |
| { |
| int i; |
| char zerobuf[8]; |
| |
| memset (zerobuf, 0, 8); |
| for (i = 0; i < arm_num_regs; i++) |
| if (arm_regmap[i] != -1) |
| supply_register (i, ((char *) buf) + arm_regmap[i]); |
| else |
| supply_register (i, zerobuf); |
| } |
| |
| static void |
| arm_fill_wmmxregset (void *buf) |
| { |
| int i; |
| |
| if (!(arm_hwcap & HWCAP_IWMMXT)) |
| return; |
| |
| for (i = 0; i < 16; i++) |
| collect_register (arm_num_regs + i, (char *) buf + i * 8); |
| |
| /* We only have access to wcssf, wcasf, and wcgr0-wcgr3. */ |
| for (i = 0; i < 6; i++) |
| collect_register (arm_num_regs + i + 16, (char *) buf + 16 * 8 + i * 4); |
| } |
| |
| static void |
| arm_store_wmmxregset (const void *buf) |
| { |
| int i; |
| |
| if (!(arm_hwcap & HWCAP_IWMMXT)) |
| return; |
| |
| for (i = 0; i < 16; i++) |
| supply_register (arm_num_regs + i, (char *) buf + i * 8); |
| |
| /* We only have access to wcssf, wcasf, and wcgr0-wcgr3. */ |
| for (i = 0; i < 6; i++) |
| supply_register (arm_num_regs + i + 16, (char *) buf + 16 * 8 + i * 4); |
| } |
| |
| static void |
| arm_fill_vfpregset (void *buf) |
| { |
| int i, num, base; |
| |
| if (!(arm_hwcap & HWCAP_VFP)) |
| return; |
| |
| if ((arm_hwcap & (HWCAP_VFPv3 | HWCAP_VFPv3D16)) == HWCAP_VFPv3) |
| num = 32; |
| else |
| num = 16; |
| |
| base = find_regno ("d0"); |
| for (i = 0; i < num; i++) |
| collect_register (base + i, (char *) buf + i * 8); |
| |
| collect_register_by_name ("fpscr", (char *) buf + 32 * 8); |
| } |
| |
| static void |
| arm_store_vfpregset (const void *buf) |
| { |
| int i, num, base; |
| |
| if (!(arm_hwcap & HWCAP_VFP)) |
| return; |
| |
| if ((arm_hwcap & (HWCAP_VFPv3 | HWCAP_VFPv3D16)) == HWCAP_VFPv3) |
| num = 32; |
| else |
| num = 16; |
| |
| base = find_regno ("d0"); |
| for (i = 0; i < num; i++) |
| supply_register (base + i, (char *) buf + i * 8); |
| |
| supply_register_by_name ("fpscr", (char *) buf + 32 * 8); |
| } |
| |
| extern int debug_threads; |
| |
| static CORE_ADDR |
| arm_get_pc () |
| { |
| unsigned long pc; |
| collect_register_by_name ("pc", &pc); |
| if (debug_threads) |
| fprintf (stderr, "stop pc is %08lx\n", pc); |
| return pc; |
| } |
| |
| static void |
| arm_set_pc (CORE_ADDR pc) |
| { |
| unsigned long newpc = pc; |
| supply_register_by_name ("pc", &newpc); |
| } |
| |
| /* Correct in either endianness. */ |
| static const unsigned long arm_breakpoint = 0xef9f0001; |
| #define arm_breakpoint_len 4 |
| static const unsigned short thumb_breakpoint = 0xde01; |
| #define thumb_breakpoint_len 2 |
| |
| /* For new EABI binaries. We recognize it regardless of which ABI |
| is used for gdbserver, so single threaded debugging should work |
| OK, but for multi-threaded debugging we only insert the current |
| ABI's breakpoint instruction. For now at least. */ |
| static const unsigned long arm_eabi_breakpoint = 0xe7f001f0; |
| |
| static int |
| arm_breakpoint_at (CORE_ADDR where) |
| { |
| unsigned long cpsr; |
| |
| collect_register_by_name ("cpsr", &cpsr); |
| |
| if (cpsr & 0x20) |
| { |
| /* Thumb mode. */ |
| unsigned short insn; |
| |
| (*the_target->read_memory) (where, (unsigned char *) &insn, 2); |
| if (insn == thumb_breakpoint) |
| return 1; |
| } |
| else |
| { |
| /* ARM mode. */ |
| unsigned long insn; |
| |
| (*the_target->read_memory) (where, (unsigned char *) &insn, 4); |
| if (insn == arm_breakpoint) |
| return 1; |
| |
| if (insn == arm_eabi_breakpoint) |
| return 1; |
| } |
| |
| return 0; |
| } |
| |
| /* We only place breakpoints in empty marker functions, and thread locking |
| is outside of the function. So rather than importing software single-step, |
| we can just run until exit. */ |
| static CORE_ADDR |
| arm_reinsert_addr () |
| { |
| unsigned long pc; |
| collect_register_by_name ("lr", &pc); |
| return pc; |
| } |
| |
| /* Fetch the thread-local storage pointer for libthread_db. */ |
| |
| ps_err_e |
| ps_get_thread_area (const struct ps_prochandle *ph, |
| lwpid_t lwpid, int idx, void **base) |
| { |
| if (ptrace (PTRACE_GET_THREAD_AREA, lwpid, NULL, base) != 0) |
| return PS_ERR; |
| |
| /* IDX is the bias from the thread pointer to the beginning of the |
| thread descriptor. It has to be subtracted due to implementation |
| quirks in libthread_db. */ |
| *base = (void *) ((char *)*base - idx); |
| |
| return PS_OK; |
| } |
| |
| static int |
| arm_get_hwcap (unsigned long *valp) |
| { |
| unsigned char *data = alloca (8); |
| int offset = 0; |
| |
| while ((*the_target->read_auxv) (offset, data, 8) == 8) |
| { |
| unsigned int *data_p = (unsigned int *)data; |
| if (data_p[0] == AT_HWCAP) |
| { |
| *valp = data_p[1]; |
| return 1; |
| } |
| |
| offset += 8; |
| } |
| |
| *valp = 0; |
| return 0; |
| } |
| |
| static void |
| arm_arch_setup (void) |
| { |
| arm_hwcap = 0; |
| if (arm_get_hwcap (&arm_hwcap) == 0) |
| { |
| init_registers_arm (); |
| return; |
| } |
| |
| if (arm_hwcap & HWCAP_IWMMXT) |
| { |
| init_registers_arm_with_iwmmxt (); |
| return; |
| } |
| |
| if (arm_hwcap & HWCAP_VFP) |
| { |
| int pid; |
| char *buf; |
| |
| /* NEON implies either no VFP, or VFPv3-D32. We only support |
| it with VFP. */ |
| if (arm_hwcap & HWCAP_NEON) |
| init_registers_arm_with_neon (); |
| else if ((arm_hwcap & (HWCAP_VFPv3 | HWCAP_VFPv3D16)) == HWCAP_VFPv3) |
| init_registers_arm_with_vfpv3 (); |
| else |
| init_registers_arm_with_vfpv2 (); |
| |
| /* Now make sure that the kernel supports reading these |
| registers. Support was added in 2.6.30. */ |
| pid = lwpid_of (get_thread_lwp (current_inferior)); |
| errno = 0; |
| buf = malloc (32 * 8 + 4); |
| if (ptrace (PTRACE_GETVFPREGS, pid, 0, buf) < 0 |
| && errno == EIO) |
| { |
| arm_hwcap = 0; |
| init_registers_arm (); |
| } |
| free (buf); |
| |
| return; |
| } |
| |
| /* The default configuration uses legacy FPA registers, probably |
| simulated. */ |
| init_registers_arm (); |
| } |
| |
| struct regset_info target_regsets[] = { |
| { PTRACE_GETREGS, PTRACE_SETREGS, 18 * 4, |
| GENERAL_REGS, |
| arm_fill_gregset, arm_store_gregset }, |
| { PTRACE_GETWMMXREGS, PTRACE_SETWMMXREGS, 16 * 8 + 6 * 4, |
| EXTENDED_REGS, |
| arm_fill_wmmxregset, arm_store_wmmxregset }, |
| { PTRACE_GETVFPREGS, PTRACE_SETVFPREGS, 32 * 8 + 4, |
| EXTENDED_REGS, |
| arm_fill_vfpregset, arm_store_vfpregset }, |
| { 0, 0, -1, -1, NULL, NULL } |
| }; |
| |
| struct linux_target_ops the_low_target = { |
| arm_arch_setup, |
| arm_num_regs, |
| arm_regmap, |
| arm_cannot_fetch_register, |
| arm_cannot_store_register, |
| arm_get_pc, |
| arm_set_pc, |
| |
| /* Define an ARM-mode breakpoint; we only set breakpoints in the C |
| library, which is most likely to be ARM. If the kernel supports |
| clone events, we will never insert a breakpoint, so even a Thumb |
| C library will work; so will mixing EABI/non-EABI gdbserver and |
| application. */ |
| #ifndef __ARM_EABI__ |
| (const unsigned char *) &arm_breakpoint, |
| #else |
| (const unsigned char *) &arm_eabi_breakpoint, |
| #endif |
| arm_breakpoint_len, |
| arm_reinsert_addr, |
| 0, |
| arm_breakpoint_at, |
| }; |