blob: 2eb5a2df17b9e6a5c58dcca714716b74cb5cd077 [file] [log] [blame]
/* GNU/Linux/MIPS specific low level interface, for the remote server for GDB.
Copyright (C) 2022-2024 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 "tdesc.h"
#include "linux-low.h"
#include <sys/ptrace.h>
#include "gdb_proc_service.h"
#include <asm/ptrace.h>
#include <elf.h>
#include "arch/csky.h"
/* Linux target op definitions for the CSKY architecture. */
class csky_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;
bool supports_z_point_type (char z_type) override;
bool supports_hardware_single_step () override;
protected:
void low_arch_setup () override;
bool low_cannot_fetch_register (int regno) override;
bool low_cannot_store_register (int regno) 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 csky_target the_csky_target;
/* Return the ptrace "address" of register REGNO. */
static int csky_regmap[] = {
0*4, 1*4, 2*4, 3*4, 4*4, 5*4, 6*4, 7*4,
8*4, 9*4, 10*4, 11*4, 12*4, 13*4, 14*4, 15*4,
16*4, 17*4, 18*4, 19*4, 20*4, 21*4, 22*4, 23*4,
24*4, 25*4, 26*4, 27*4, 28*4, 29*4, 30*4, 31*4,
-1, -1, -1, -1, 34*4, 35*4, -1, -1,
40*4, 42*4, 44*4, 46*4, 48*4, 50*4, 52*4, 54*4, /* fr0 ~ fr15, 64bit */
56*4, 58*4, 60*4, 62*4, 64*4, 66*4, 68*4, 70*4,
72*4, 76*4, 80*4, 84*4, 88*4, 92*4, 96*4,100*4, /* vr0 ~ vr15, 128bit */
104*4,108*4,112*4,116*4,120*4,124*4,128*4,132*4,
33*4, /* pc */
-1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1,
32*4, -1, -1, -1, -1, -1, -1, -1, /* psr */
-1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1,
73*4, 72*4, 74*4, -1, -1, -1, 14*4, /* fcr, fid, fesr, usp */
};
/* CSKY software breakpoint instruction code. */
/* When the kernel code version is behind v4.x,
illegal insn 0x1464 will be a software bkpt trigger.
When an illegal insn exception happens, the case
that insn at EPC is 0x1464 will be recognized as SIGTRAP. */
static unsigned short csky_breakpoint_illegal_2_v2 = 0x1464;
static unsigned int csky_breakpoint_illegal_4_v2 = 0x14641464;
bool
csky_target::low_cannot_fetch_register (int regno)
{
if (csky_regmap[regno] == -1)
return true;
return false;
}
bool
csky_target::low_cannot_store_register (int regno)
{
if (csky_regmap[regno] == -1)
return true;
return false;
}
/* Get the value of pc register. */
CORE_ADDR
csky_target::low_get_pc (struct regcache *regcache)
{
unsigned long pc;
collect_register_by_name (regcache, "pc", &pc);
return pc;
}
/* Set pc register. */
void
csky_target::low_set_pc (struct regcache *regcache, CORE_ADDR pc)
{
unsigned long new_pc = pc;
supply_register_by_name (regcache, "pc", &new_pc);
}
void
csky_target::low_arch_setup ()
{
static const char *expedite_regs[] = { "r14", "pc", NULL };
target_desc_up tdesc = csky_create_target_description ();
if (tdesc->expedite_regs.empty ())
{
init_target_desc (tdesc.get (), expedite_regs);
gdb_assert (!tdesc->expedite_regs.empty ());
}
current_process ()->tdesc = tdesc.release ();
return;
}
/* 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)
{
struct pt_regs regset;
if (ptrace (PTRACE_GETREGSET, lwpid,
(PTRACE_TYPE_ARG3) (long) NT_PRSTATUS, &regset) != 0)
return PS_ERR;
*base = (void *) regset.tls;
/* 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;
}
/* Gdbserver uses PTRACE_GET/SET_RGESET. */
static void
csky_fill_pt_gregset (struct regcache *regcache, void *buf)
{
int i, base;
struct pt_regs *regset = (struct pt_regs *)buf;
collect_register_by_name (regcache, "r15", &regset->lr);
collect_register_by_name (regcache, "pc", &regset->pc);
collect_register_by_name (regcache, "psr", &regset->sr);
collect_register_by_name (regcache, "r14", &regset->usp);
collect_register_by_name (regcache, "r0", &regset->a0);
collect_register_by_name (regcache, "r1", &regset->a1);
collect_register_by_name (regcache, "r2", &regset->a2);
collect_register_by_name (regcache, "r3", &regset->a3);
base = find_regno (regcache->tdesc, "r4");
for (i = 0; i < 10; i++)
collect_register (regcache, base + i, &regset->regs[i]);
base = find_regno (regcache->tdesc, "r16");
for (i = 0; i < 16; i++)
collect_register (regcache, base + i, &regset->exregs[i]);
collect_register_by_name (regcache, "hi", &regset->rhi);
collect_register_by_name (regcache, "lo", &regset->rlo);
}
static void
csky_store_pt_gregset (struct regcache *regcache, const void *buf)
{
int i, base;
const struct pt_regs *regset = (const struct pt_regs *) buf;
supply_register_by_name (regcache, "r15", &regset->lr);
supply_register_by_name (regcache, "pc", &regset->pc);
supply_register_by_name (regcache, "psr", &regset->sr);
supply_register_by_name (regcache, "r14", &regset->usp);
supply_register_by_name (regcache, "r0", &regset->a0);
supply_register_by_name (regcache, "r1", &regset->a1);
supply_register_by_name (regcache, "r2", &regset->a2);
supply_register_by_name (regcache, "r3", &regset->a3);
base = find_regno (regcache->tdesc, "r4");
for (i = 0; i < 10; i++)
supply_register (regcache, base + i, &regset->regs[i]);
base = find_regno (regcache->tdesc, "r16");
for (i = 0; i < 16; i++)
supply_register (regcache, base + i, &regset->exregs[i]);
supply_register_by_name (regcache, "hi", &regset->rhi);
supply_register_by_name (regcache, "lo", &regset->rlo);
}
static void
csky_fill_pt_vrregset (struct regcache *regcache, void *buf)
{
int i, base;
struct user_fp *regset = (struct user_fp *)buf;
base = find_regno (regcache->tdesc, "vr0");
for (i = 0; i < 16; i++)
collect_register (regcache, base + i, &regset->vr[i * 4]);
collect_register_by_name (regcache, "fcr", &regset->fcr);
collect_register_by_name (regcache, "fesr", &regset->fesr);
collect_register_by_name (regcache, "fid", &regset->fid);
}
static void
csky_store_pt_vrregset (struct regcache *regcache, const void *buf)
{
int i, base;
const struct user_fp *regset = (const struct user_fp *)buf;
base = find_regno (regcache->tdesc, "vr0");
for (i = 0; i < 16; i++)
supply_register (regcache, base + i, &regset->vr[i * 4]);
base = find_regno (regcache->tdesc, "fr0");
for (i = 0; i < 16; i++)
supply_register (regcache, base + i, &regset->vr[i * 4]);
supply_register_by_name (regcache, "fcr", &regset->fcr);
supply_register_by_name (regcache, "fesr", &regset->fesr);
supply_register_by_name (regcache, "fid", &regset->fid);
}
struct regset_info csky_regsets[] = {
{ PTRACE_GETREGSET, PTRACE_SETREGSET, NT_PRSTATUS, sizeof(struct pt_regs),
GENERAL_REGS, csky_fill_pt_gregset, csky_store_pt_gregset},
{ PTRACE_GETREGSET, PTRACE_SETREGSET, NT_FPREGSET, sizeof(struct user_fp),
FP_REGS, csky_fill_pt_vrregset, csky_store_pt_vrregset},
NULL_REGSET
};
static struct regsets_info csky_regsets_info =
{
csky_regsets, /* Regsets */
0, /* Num_regsets */
NULL, /* Disabled_regsets */
};
static struct regs_info csky_regs_info =
{
NULL, /* FIXME: what's this */
NULL, /* PEEKUSER/POKEUSR isn't supported by kernel > 4.x */
&csky_regsets_info
};
const regs_info *
csky_target::get_regs_info ()
{
return &csky_regs_info;
}
/* Implementation of linux_target_ops method "sw_breakpoint_from_kind". */
const gdb_byte *
csky_target::sw_breakpoint_from_kind (int kind, int *size)
{
if (kind == 4)
{
*size = 4;
return (const gdb_byte *) &csky_breakpoint_illegal_4_v2;
}
else
{
*size = 2;
return (const gdb_byte *) &csky_breakpoint_illegal_2_v2;
}
}
bool
csky_target::supports_z_point_type (char z_type)
{
/* FIXME: hardware breakpoint support ?? */
if (z_type == Z_PACKET_SW_BP)
return true;
return false;
}
bool
csky_target::low_breakpoint_at (CORE_ADDR where)
{
unsigned int insn;
/* Here just read 2 bytes, as csky_breakpoint_illegal_4_v2
is double of csky_breakpoint_illegal_2_v2, csky_breakpoint_bkpt_4
is double of csky_breakpoint_bkpt_2. Others are 2 bytes bkpt. */
read_memory (where, (unsigned char *) &insn, 2);
if (insn == csky_breakpoint_illegal_2_v2)
return true;
return false;
}
/* Support for hardware single step. */
bool
csky_target::supports_hardware_single_step ()
{
return true;
}
/* The linux target ops object. */
linux_process_target *the_linux_target = &the_csky_target;
void
initialize_low_arch (void)
{
initialize_regsets_info (&csky_regsets_info);
}