From 4933265c3f71b9134363d0c05f09542d5cc677f4 Mon Sep 17 00:00:00 2001 From: Stafford Horne Date: Sun, 16 Aug 2020 06:04:05 +0900 Subject: [PATCH] gdb: or1k: implement gdb server This patch adds gdbserver support for OpenRISC. This has been used for debugging the glibc port that in being worked on here: https://github.com/openrisc/or1k-glibc/tree/or1k-port-2 Hence the comment about registers definitions being inline with glibc. --- gdb/features/Makefile | 1 + gdb/features/or1k-linux.xml | 13 ++ gdb/regformats/or1k-linux.dat | 40 +++++ gdbserver/Makefile.in | 1 + gdbserver/configure.srv | 8 + gdbserver/linux-or1k-low.cc | 266 ++++++++++++++++++++++++++++++++++ 6 files changed, 329 insertions(+) create mode 100644 gdb/features/or1k-linux.xml create mode 100644 gdb/regformats/or1k-linux.dat create mode 100644 gdbserver/linux-or1k-low.cc diff --git a/gdb/features/Makefile b/gdb/features/Makefile index e478bf838b7..311176aba28 100644 --- a/gdb/features/Makefile +++ b/gdb/features/Makefile @@ -47,6 +47,7 @@ WHICH = mips-linux mips-dsp-linux \ mips64-linux mips64-dsp-linux \ nios2-linux \ + or1k-linux \ rs6000/powerpc-32 \ rs6000/powerpc-32l rs6000/powerpc-altivec32l rs6000/powerpc-e500l \ rs6000/powerpc-64l rs6000/powerpc-altivec64l rs6000/powerpc-vsx32l \ diff --git a/gdb/features/or1k-linux.xml b/gdb/features/or1k-linux.xml new file mode 100644 index 00000000000..598538d124f --- /dev/null +++ b/gdb/features/or1k-linux.xml @@ -0,0 +1,13 @@ + + + + + + or1k + GNU/Linux + + diff --git a/gdb/regformats/or1k-linux.dat b/gdb/regformats/or1k-linux.dat new file mode 100644 index 00000000000..7b64646fc65 --- /dev/null +++ b/gdb/regformats/or1k-linux.dat @@ -0,0 +1,40 @@ +# THIS FILE IS GENERATED. -*- buffer-read-only: t -*- vi :set ro: +# Generated from: or1k-linux.xml +name:or1k_linux +xmltarget:or1k-linux.xml +expedite:r1,npc +32:r0 +32:r1 +32:r2 +32:r3 +32:r4 +32:r5 +32:r6 +32:r7 +32:r8 +32:r9 +32:r10 +32:r11 +32:r12 +32:r13 +32:r14 +32:r15 +32:r16 +32:r17 +32:r18 +32:r19 +32:r20 +32:r21 +32:r22 +32:r23 +32:r24 +32:r25 +32:r26 +32:r27 +32:r28 +32:r29 +32:r30 +32:r31 +32:ppc +32:npc +32:sr diff --git a/gdbserver/Makefile.in b/gdbserver/Makefile.in index 0a2381bf51c..71c3c4ad959 100644 --- a/gdbserver/Makefile.in +++ b/gdbserver/Makefile.in @@ -180,6 +180,7 @@ SFILES = \ $(srcdir)/linux-m68k-low.cc \ $(srcdir)/linux-mips-low.cc \ $(srcdir)/linux-nios2-low.cc \ + $(srcdir)/linux-or1k-low.cc \ $(srcdir)/linux-ppc-low.cc \ $(srcdir)/linux-riscv-low.cc \ $(srcdir)/linux-s390-low.cc \ diff --git a/gdbserver/configure.srv b/gdbserver/configure.srv index 971f537bffa..6e09b0eeb79 100644 --- a/gdbserver/configure.srv +++ b/gdbserver/configure.srv @@ -175,6 +175,14 @@ case "${gdbserver_host}" in srv_linux_usrregs=yes srv_linux_thread_db=yes ;; + or1k*-*-linux*) srv_regobj="or1k-linux.o" + srv_tgtobj="$srv_linux_obj linux-or1k-low.o" + srv_xmlfiles="or1k-linux.xml" + srv_xmlfiles="${srv_xmlfiles} or1k-core.xml" + srv_linux_regsets=yes + srv_linux_usrregs=yes + srv_linux_thread_db=yes + ;; powerpc*-*-linux*) srv_regobj="powerpc-32l.o" srv_regobj="${srv_regobj} powerpc-altivec32l.o" srv_regobj="${srv_regobj} powerpc-vsx32l.o" diff --git a/gdbserver/linux-or1k-low.cc b/gdbserver/linux-or1k-low.cc new file mode 100644 index 00000000000..46d03f2651a --- /dev/null +++ b/gdbserver/linux-or1k-low.cc @@ -0,0 +1,266 @@ +/* GNU/Linux/OR1K specific low level interface for the GDB server. + Copyright (C) 2021 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 . */ + +#include "server.h" +#include "linux-low.h" +#include "elf/common.h" +#include "nat/gdb_ptrace.h" +#include +#include "gdb_proc_service.h" +#include + +#ifndef PTRACE_GET_THREAD_AREA +#define PTRACE_GET_THREAD_AREA 25 +#endif + +/* Linux target op definitions for the OpenRISC architecture. */ + +class or1k_target : public linux_process_target +{ +public: + + const regs_info *get_regs_info () override; + + const gdb_byte *sw_breakpoint_from_kind (int kind, int *size) override; + +protected: + + void low_arch_setup () override; + + bool low_cannot_fetch_register (int regno) override; + + bool low_cannot_store_register (int regno) override; + + bool low_supports_breakpoints () override; + + CORE_ADDR low_get_pc (regcache *regcache) override; + + void low_set_pc (regcache *regcache, CORE_ADDR newpc) override; + + bool low_breakpoint_at (CORE_ADDR pc) override; +}; + +/* The singleton target ops object. */ + +static or1k_target the_or1k_target; + +bool +or1k_target::low_supports_breakpoints () +{ + return true; +} + +CORE_ADDR +or1k_target::low_get_pc (regcache *regcache) +{ + return linux_get_pc_32bit (regcache); +} + +void +or1k_target::low_set_pc (regcache *regcache, CORE_ADDR pc) +{ + linux_set_pc_32bit (regcache, pc); +} + +/* The following definition must agree with the number of registers + defined in "struct user_regs" in GLIBC + (sysdeps/unix/sysv/linux/or1k/sys/ucontext.h), and also with + OR1K_NUM_REGS in GDB proper. */ + +#define or1k_num_regs 35 + +/* Defined in auto-generated file or1k-linux.c. */ + +void init_registers_or1k_linux (void); +extern const struct target_desc *tdesc_or1k_linux; + +/* This union is used to convert between int and byte buffer + representations of register contents. */ + +union or1k_register +{ + unsigned char buf[4]; + int reg32; +}; + +/* Return the ptrace ``address'' of register REGNO. */ + +static int or1k_regmap[] = { + -1, 1, 2, 3, 4, 5, 6, 7, + 8, 9, 10, 11, 12, 13, 14, 15, + 16, 17, 18, 19, 20, 21, 22, 23, + 24, 25, 26, 27, 28, 29, 30, 31, + -1, /* PC */ + -1, /* ORIGINAL R11 */ + -1 /* SYSCALL NO */ +}; + +/* Implement the low_arch_setup linux target ops method. */ + +void +or1k_target::low_arch_setup () +{ + current_process ()->tdesc = tdesc_or1k_linux; +} + +/* Implement the low_cannot_fetch_register linux target ops method. */ + +bool +or1k_target::low_cannot_fetch_register (int regno) +{ + return (or1k_regmap[regno] == -1); +} + +/* Implement the low_cannot_store_register linux target ops method. */ + +bool +or1k_target::low_cannot_store_register (int regno) +{ + return (or1k_regmap[regno] == -1); +} + +/* Breakpoint support. */ + +static const unsigned int or1k_breakpoint = 0x21000001; +#define or1k_breakpoint_len 4 + +/* Implementation of target ops method "sw_breakpoint_from_kind". */ + +const gdb_byte * +or1k_target::sw_breakpoint_from_kind (int kind, int *size) +{ + *size = or1k_breakpoint_len; + return (const gdb_byte *) &or1k_breakpoint; +} + +/* Implement the low_breakpoint_at linux target ops method. */ + +bool +or1k_target::low_breakpoint_at (CORE_ADDR where) +{ + unsigned int insn; + + read_memory (where, (unsigned char *) &insn, or1k_breakpoint_len); + if (insn == or1k_breakpoint) + return true; + return false; +} + +/* Fetch the thread-local storage pointer for libthread_db. */ + +ps_err_e +ps_get_thread_area (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; +} + +/* Helper functions to collect/supply a single register REGNO. */ + +static void +or1k_collect_register (struct regcache *regcache, int regno, + union or1k_register *reg) +{ + union or1k_register tmp_reg; + + collect_register (regcache, regno, &tmp_reg.reg32); + reg->reg32 = tmp_reg.reg32; +} + +static void +or1k_supply_register (struct regcache *regcache, int regno, + const union or1k_register *reg) +{ + supply_register (regcache, regno, reg->buf); +} + +/* We have only a single register set on OpenRISC. */ + +static void +or1k_fill_gregset (struct regcache *regcache, void *buf) +{ + union or1k_register *regset = (union or1k_register *) buf; + int i; + + for (i = 1; i < or1k_num_regs; i++) + or1k_collect_register (regcache, i, regset + i); +} + +static void +or1k_store_gregset (struct regcache *regcache, const void *buf) +{ + const union or1k_register *regset = (union or1k_register *) buf; + int i; + + for (i = 0; i < or1k_num_regs; i++) + or1k_supply_register (regcache, i, regset + i); +} + +static struct regset_info or1k_regsets[] = +{ + { PTRACE_GETREGSET, PTRACE_SETREGSET, NT_PRSTATUS, + or1k_num_regs * 4, GENERAL_REGS, + or1k_fill_gregset, or1k_store_gregset }, + NULL_REGSET +}; + +static struct regsets_info or1k_regsets_info = + { + or1k_regsets, /* regsets */ + 0, /* num_regsets */ + NULL, /* disabled_regsets */ + }; + +static struct usrregs_info or1k_usrregs_info = + { + or1k_num_regs, + or1k_regmap, + }; + +static struct regs_info or1k_regs = + { + NULL, /* regset_bitmap */ + &or1k_usrregs_info, + &or1k_regsets_info + }; + +const regs_info * +or1k_target::get_regs_info () +{ + return &or1k_regs; +} + +/* The linux target ops object. */ + +linux_process_target *the_linux_target = &the_or1k_target; + +void +initialize_low_arch (void) +{ + init_registers_or1k_linux (); + + initialize_regsets_info (&or1k_regsets_info); +} -- 2.30.2