binutils-gdb/gdb/gdbserver/spu-low.c

601 lines
14 KiB
C

/* Low level interface to SPUs, for the remote server for GDB.
Copyright (C) 2006, 2007, 2008 Free Software Foundation, Inc.
Contributed by Ulrich Weigand <uweigand@de.ibm.com>.
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 <sys/wait.h>
#include <stdio.h>
#include <sys/ptrace.h>
#include <fcntl.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <sys/syscall.h>
/* Some older glibc versions do not define this. */
#ifndef __WNOTHREAD
#define __WNOTHREAD 0x20000000 /* Don't wait on children of other
threads in this group */
#endif
#define PTRACE_TYPE_RET long
#define PTRACE_TYPE_ARG3 long
/* Number of registers. */
#define SPU_NUM_REGS 130
#define SPU_NUM_CORE_REGS 128
/* Special registers. */
#define SPU_ID_REGNUM 128
#define SPU_PC_REGNUM 129
/* PPU side system calls. */
#define INSTR_SC 0x44000002
#define NR_spu_run 0x0116
/* Get current thread ID (Linux task ID). */
#define current_tid ((struct inferior_list_entry *)current_inferior)->id
/* These are used in remote-utils.c. */
int using_threads = 0;
/* Defined in auto-generated file reg-spu.c. */
void init_registers_spu (void);
/* Fetch PPU register REGNO. */
static CORE_ADDR
fetch_ppc_register (int regno)
{
PTRACE_TYPE_RET res;
int tid = current_tid;
#ifndef __powerpc64__
/* If running as a 32-bit process on a 64-bit system, we attempt
to get the full 64-bit register content of the target process.
If the PPC special ptrace call fails, we're on a 32-bit system;
just fall through to the regular ptrace call in that case. */
{
char buf[8];
errno = 0;
ptrace (PPC_PTRACE_PEEKUSR_3264, tid,
(PTRACE_TYPE_ARG3) (regno * 8), buf);
if (errno == 0)
ptrace (PPC_PTRACE_PEEKUSR_3264, tid,
(PTRACE_TYPE_ARG3) (regno * 8 + 4), buf + 4);
if (errno == 0)
return (CORE_ADDR) *(unsigned long long *)buf;
}
#endif
errno = 0;
res = ptrace (PT_READ_U, tid,
(PTRACE_TYPE_ARG3) (regno * sizeof (PTRACE_TYPE_RET)), 0);
if (errno != 0)
{
char mess[128];
sprintf (mess, "reading PPC register #%d", regno);
perror_with_name (mess);
}
return (CORE_ADDR) (unsigned long) res;
}
/* Fetch WORD from PPU memory at (aligned) MEMADDR in thread TID. */
static int
fetch_ppc_memory_1 (int tid, CORE_ADDR memaddr, PTRACE_TYPE_RET *word)
{
errno = 0;
#ifndef __powerpc64__
if (memaddr >> 32)
{
unsigned long long addr_8 = (unsigned long long) memaddr;
ptrace (PPC_PTRACE_PEEKTEXT_3264, tid, (PTRACE_TYPE_ARG3) &addr_8, word);
}
else
#endif
*word = ptrace (PT_READ_I, tid, (PTRACE_TYPE_ARG3) (size_t) memaddr, 0);
return errno;
}
/* Store WORD into PPU memory at (aligned) MEMADDR in thread TID. */
static int
store_ppc_memory_1 (int tid, CORE_ADDR memaddr, PTRACE_TYPE_RET word)
{
errno = 0;
#ifndef __powerpc64__
if (memaddr >> 32)
{
unsigned long long addr_8 = (unsigned long long) memaddr;
ptrace (PPC_PTRACE_POKEDATA_3264, tid, (PTRACE_TYPE_ARG3) &addr_8, word);
}
else
#endif
ptrace (PT_WRITE_D, tid, (PTRACE_TYPE_ARG3) (size_t) memaddr, word);
return errno;
}
/* Fetch LEN bytes of PPU memory at MEMADDR to MYADDR. */
static int
fetch_ppc_memory (CORE_ADDR memaddr, char *myaddr, int len)
{
int i, ret;
CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_TYPE_RET);
int count = ((((memaddr + len) - addr) + sizeof (PTRACE_TYPE_RET) - 1)
/ sizeof (PTRACE_TYPE_RET));
PTRACE_TYPE_RET *buffer;
int tid = current_tid;
buffer = (PTRACE_TYPE_RET *) alloca (count * sizeof (PTRACE_TYPE_RET));
for (i = 0; i < count; i++, addr += sizeof (PTRACE_TYPE_RET))
if ((ret = fetch_ppc_memory_1 (tid, addr, &buffer[i])) != 0)
return ret;
memcpy (myaddr,
(char *) buffer + (memaddr & (sizeof (PTRACE_TYPE_RET) - 1)),
len);
return 0;
}
/* Store LEN bytes from MYADDR to PPU memory at MEMADDR. */
static int
store_ppc_memory (CORE_ADDR memaddr, char *myaddr, int len)
{
int i, ret;
CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_TYPE_RET);
int count = ((((memaddr + len) - addr) + sizeof (PTRACE_TYPE_RET) - 1)
/ sizeof (PTRACE_TYPE_RET));
PTRACE_TYPE_RET *buffer;
int tid = current_tid;
buffer = (PTRACE_TYPE_RET *) alloca (count * sizeof (PTRACE_TYPE_RET));
if (addr != memaddr || len < (int) sizeof (PTRACE_TYPE_RET))
if ((ret = fetch_ppc_memory_1 (tid, addr, &buffer[0])) != 0)
return ret;
if (count > 1)
if ((ret = fetch_ppc_memory_1 (tid, addr + (count - 1)
* sizeof (PTRACE_TYPE_RET),
&buffer[count - 1])) != 0)
return ret;
memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_TYPE_RET) - 1)),
myaddr, len);
for (i = 0; i < count; i++, addr += sizeof (PTRACE_TYPE_RET))
if ((ret = store_ppc_memory_1 (tid, addr, buffer[i])) != 0)
return ret;
return 0;
}
/* If the PPU thread is currently stopped on a spu_run system call,
return to FD and ADDR the file handle and NPC parameter address
used with the system call. Return non-zero if successful. */
static int
parse_spufs_run (int *fd, CORE_ADDR *addr)
{
char buf[4];
CORE_ADDR pc = fetch_ppc_register (32); /* nip */
/* Fetch instruction preceding current NIP. */
if (fetch_ppc_memory (pc-4, buf, 4) != 0)
return 0;
/* It should be a "sc" instruction. */
if (*(unsigned int *)buf != INSTR_SC)
return 0;
/* System call number should be NR_spu_run. */
if (fetch_ppc_register (0) != NR_spu_run)
return 0;
/* Register 3 contains fd, register 4 the NPC param pointer. */
*fd = fetch_ppc_register (34); /* orig_gpr3 */
*addr = fetch_ppc_register (4);
return 1;
}
/* Copy LEN bytes at OFFSET in spufs file ANNEX into/from READBUF or WRITEBUF,
using the /proc file system. */
static int
spu_proc_xfer_spu (const char *annex, unsigned char *readbuf,
const unsigned char *writebuf,
CORE_ADDR offset, int len)
{
char buf[128];
int fd = 0;
int ret = -1;
if (!annex)
return 0;
sprintf (buf, "/proc/%ld/fd/%s", current_tid, annex);
fd = open (buf, writebuf? O_WRONLY : O_RDONLY);
if (fd <= 0)
return -1;
if (offset != 0
&& lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
{
close (fd);
return 0;
}
if (writebuf)
ret = write (fd, writebuf, (size_t) len);
else if (readbuf)
ret = read (fd, readbuf, (size_t) len);
close (fd);
return ret;
}
/* Start an inferior process and returns its pid.
ALLARGS is a vector of program-name and args. */
static int
spu_create_inferior (char *program, char **allargs)
{
int pid;
pid = fork ();
if (pid < 0)
perror_with_name ("fork");
if (pid == 0)
{
ptrace (PTRACE_TRACEME, 0, 0, 0);
setpgid (0, 0);
execv (program, allargs);
if (errno == ENOENT)
execvp (program, allargs);
fprintf (stderr, "Cannot exec %s: %s.\n", program,
strerror (errno));
fflush (stderr);
_exit (0177);
}
add_thread (pid, NULL, pid);
return pid;
}
/* Attach to an inferior process. */
int
spu_attach (unsigned long pid)
{
if (ptrace (PTRACE_ATTACH, pid, 0, 0) != 0)
{
fprintf (stderr, "Cannot attach to process %ld: %s (%d)\n", pid,
strerror (errno), errno);
fflush (stderr);
_exit (0177);
}
add_thread (pid, NULL, pid);
return 0;
}
/* Kill the inferior process. */
static void
spu_kill (void)
{
ptrace (PTRACE_KILL, current_tid, 0, 0);
}
/* Detach from inferior process. */
static int
spu_detach (void)
{
ptrace (PTRACE_DETACH, current_tid, 0, 0);
return 0;
}
static void
spu_join (void)
{
int status, ret;
do {
ret = waitpid (current_tid, &status, 0);
if (WIFEXITED (status) || WIFSIGNALED (status))
break;
} while (ret != -1 || errno != ECHILD);
}
/* Return nonzero if the given thread is still alive. */
static int
spu_thread_alive (unsigned long tid)
{
return tid == current_tid;
}
/* Resume process. */
static void
spu_resume (struct thread_resume *resume_info)
{
while (resume_info->thread != -1
&& resume_info->thread != current_tid)
resume_info++;
if (resume_info->leave_stopped)
return;
/* We don't support hardware single-stepping right now, assume
GDB knows to use software single-stepping. */
if (resume_info->step)
fprintf (stderr, "Hardware single-step not supported.\n");
regcache_invalidate ();
errno = 0;
ptrace (PTRACE_CONT, current_tid, 0, resume_info->sig);
if (errno)
perror_with_name ("ptrace");
}
/* Wait for process, returns status. */
static unsigned char
spu_wait (char *status)
{
int tid = current_tid;
int w;
int ret;
while (1)
{
ret = waitpid (tid, &w, WNOHANG | __WALL | __WNOTHREAD);
if (ret == -1)
{
if (errno != ECHILD)
perror_with_name ("waitpid");
}
else if (ret > 0)
break;
usleep (1000);
}
/* On the first wait, continue running the inferior until we are
blocked inside an spu_run system call. */
if (!server_waiting)
{
int fd;
CORE_ADDR addr;
while (!parse_spufs_run (&fd, &addr))
{
ptrace (PT_SYSCALL, tid, (PTRACE_TYPE_ARG3) 0, 0);
waitpid (tid, NULL, __WALL | __WNOTHREAD);
}
}
if (WIFEXITED (w))
{
fprintf (stderr, "\nChild exited with retcode = %x \n", WEXITSTATUS (w));
*status = 'W';
clear_inferiors ();
return ((unsigned char) WEXITSTATUS (w));
}
else if (!WIFSTOPPED (w))
{
fprintf (stderr, "\nChild terminated with signal = %x \n", WTERMSIG (w));
*status = 'X';
clear_inferiors ();
return ((unsigned char) WTERMSIG (w));
}
/* After attach, we may have received a SIGSTOP. Do not return this
as signal to GDB, or else it will try to continue with SIGSTOP ... */
if (!server_waiting)
{
*status = 'T';
return 0;
}
*status = 'T';
return ((unsigned char) WSTOPSIG (w));
}
/* Fetch inferior registers. */
static void
spu_fetch_registers (int regno)
{
int fd;
CORE_ADDR addr;
/* ??? Some callers use 0 to mean all registers. */
if (regno == 0)
regno = -1;
/* We must be stopped on a spu_run system call. */
if (!parse_spufs_run (&fd, &addr))
return;
/* The ID register holds the spufs file handle. */
if (regno == -1 || regno == SPU_ID_REGNUM)
supply_register (SPU_ID_REGNUM, (char *)&fd);
/* The NPC register is found at ADDR. */
if (regno == -1 || regno == SPU_PC_REGNUM)
{
char buf[4];
if (fetch_ppc_memory (addr, buf, 4) == 0)
supply_register (SPU_PC_REGNUM, buf);
}
/* The GPRs are found in the "regs" spufs file. */
if (regno == -1 || (regno >= 0 && regno < SPU_NUM_CORE_REGS))
{
unsigned char buf[16*SPU_NUM_CORE_REGS];
char annex[32];
int i;
sprintf (annex, "%d/regs", fd);
if (spu_proc_xfer_spu (annex, buf, NULL, 0, sizeof buf) == sizeof buf)
for (i = 0; i < SPU_NUM_CORE_REGS; i++)
supply_register (i, buf + i*16);
}
}
/* Store inferior registers. */
static void
spu_store_registers (int regno)
{
int fd;
CORE_ADDR addr;
/* ??? Some callers use 0 to mean all registers. */
if (regno == 0)
regno = -1;
/* We must be stopped on a spu_run system call. */
if (!parse_spufs_run (&fd, &addr))
return;
/* The NPC register is found at ADDR. */
if (regno == -1 || regno == SPU_PC_REGNUM)
{
char buf[4];
collect_register (SPU_PC_REGNUM, buf);
store_ppc_memory (addr, buf, 4);
}
/* The GPRs are found in the "regs" spufs file. */
if (regno == -1 || (regno >= 0 && regno < SPU_NUM_CORE_REGS))
{
unsigned char buf[16*SPU_NUM_CORE_REGS];
char annex[32];
int i;
for (i = 0; i < SPU_NUM_CORE_REGS; i++)
collect_register (i, buf + i*16);
sprintf (annex, "%d/regs", fd);
spu_proc_xfer_spu (annex, NULL, buf, 0, sizeof buf);
}
}
/* Copy LEN bytes from inferior's memory starting at MEMADDR
to debugger memory starting at MYADDR. */
static int
spu_read_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len)
{
int fd, ret;
CORE_ADDR addr;
char annex[32];
/* We must be stopped on a spu_run system call. */
if (!parse_spufs_run (&fd, &addr))
return 0;
/* Use the "mem" spufs file to access SPU local store. */
sprintf (annex, "%d/mem", fd);
ret = spu_proc_xfer_spu (annex, myaddr, NULL, memaddr, len);
return ret == len ? 0 : EIO;
}
/* Copy LEN bytes of data from debugger memory at MYADDR
to inferior's memory at MEMADDR.
On failure (cannot write the inferior)
returns the value of errno. */
static int
spu_write_memory (CORE_ADDR memaddr, const unsigned char *myaddr, int len)
{
int fd, ret;
CORE_ADDR addr;
char annex[32];
/* We must be stopped on a spu_run system call. */
if (!parse_spufs_run (&fd, &addr))
return 0;
/* Use the "mem" spufs file to access SPU local store. */
sprintf (annex, "%d/mem", fd);
ret = spu_proc_xfer_spu (annex, NULL, myaddr, memaddr, len);
return ret == len ? 0 : EIO;
}
/* Look up special symbols -- unneded here. */
static void
spu_look_up_symbols (void)
{
}
/* Send signal to inferior. */
static void
spu_request_interrupt (void)
{
syscall (SYS_tkill, current_tid, SIGINT);
}
static struct target_ops spu_target_ops = {
spu_create_inferior,
spu_attach,
spu_kill,
spu_detach,
spu_join,
spu_thread_alive,
spu_resume,
spu_wait,
spu_fetch_registers,
spu_store_registers,
spu_read_memory,
spu_write_memory,
spu_look_up_symbols,
spu_request_interrupt,
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
spu_proc_xfer_spu,
hostio_last_error_from_errno,
};
void
initialize_low (void)
{
static const unsigned char breakpoint[] = { 0x00, 0x00, 0x3f, 0xff };
set_target_ops (&spu_target_ops);
set_breakpoint_data (breakpoint, sizeof breakpoint);
init_registers_spu ();
}