diff options
Diffstat (limited to 'target/nios2/nios2-semi.c')
| -rw-r--r-- | target/nios2/nios2-semi.c | 455 |
1 files changed, 455 insertions, 0 deletions
diff --git a/target/nios2/nios2-semi.c b/target/nios2/nios2-semi.c new file mode 100644 index 0000000000..cc2777d2f8 --- /dev/null +++ b/target/nios2/nios2-semi.c @@ -0,0 +1,455 @@ +/* + * Nios II Semihosting syscall interface. + * This code is derived from m68k-semi.c. + * The semihosting protocol implemented here is described in the + * libgloss sources: + * https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;a=blob;f=libgloss/nios2/nios2-semi.txt;hb=HEAD + * + * Copyright (c) 2017-2019 Mentor Graphics + * + * 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 2 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 "qemu/osdep.h" + +#include "cpu.h" +#if defined(CONFIG_USER_ONLY) +#include "qemu.h" +#else +#include "qemu-common.h" +#include "exec/gdbstub.h" +#include "exec/softmmu-semi.h" +#endif +#include "qemu/log.h" +#include "sysemu/sysemu.h" + +#define HOSTED_EXIT 0 +#define HOSTED_INIT_SIM 1 +#define HOSTED_OPEN 2 +#define HOSTED_CLOSE 3 +#define HOSTED_READ 4 +#define HOSTED_WRITE 5 +#define HOSTED_LSEEK 6 +#define HOSTED_RENAME 7 +#define HOSTED_UNLINK 8 +#define HOSTED_STAT 9 +#define HOSTED_FSTAT 10 +#define HOSTED_GETTIMEOFDAY 11 +#define HOSTED_ISATTY 12 +#define HOSTED_SYSTEM 13 + +typedef uint32_t gdb_mode_t; +typedef uint32_t gdb_time_t; + +struct nios2_gdb_stat { + uint32_t gdb_st_dev; /* device */ + uint32_t gdb_st_ino; /* inode */ + gdb_mode_t gdb_st_mode; /* protection */ + uint32_t gdb_st_nlink; /* number of hard links */ + uint32_t gdb_st_uid; /* user ID of owner */ + uint32_t gdb_st_gid; /* group ID of owner */ + uint32_t gdb_st_rdev; /* device type (if inode device) */ + uint64_t gdb_st_size; /* total size, in bytes */ + uint64_t gdb_st_blksize; /* blocksize for filesystem I/O */ + uint64_t gdb_st_blocks; /* number of blocks allocated */ + gdb_time_t gdb_st_atime; /* time of last access */ + gdb_time_t gdb_st_mtime; /* time of last modification */ + gdb_time_t gdb_st_ctime; /* time of last change */ +} QEMU_PACKED; + +struct gdb_timeval { + gdb_time_t tv_sec; /* second */ + uint64_t tv_usec; /* microsecond */ +} QEMU_PACKED; + +#define GDB_O_RDONLY 0x0 +#define GDB_O_WRONLY 0x1 +#define GDB_O_RDWR 0x2 +#define GDB_O_APPEND 0x8 +#define GDB_O_CREAT 0x200 +#define GDB_O_TRUNC 0x400 +#define GDB_O_EXCL 0x800 + +static int translate_openflags(int flags) +{ + int hf; + + if (flags & GDB_O_WRONLY) { + hf = O_WRONLY; + } else if (flags & GDB_O_RDWR) { + hf = O_RDWR; + } else { + hf = O_RDONLY; + } + + if (flags & GDB_O_APPEND) { + hf |= O_APPEND; + } + if (flags & GDB_O_CREAT) { + hf |= O_CREAT; + } + if (flags & GDB_O_TRUNC) { + hf |= O_TRUNC; + } + if (flags & GDB_O_EXCL) { + hf |= O_EXCL; + } + + return hf; +} + +static bool translate_stat(CPUNios2State *env, target_ulong addr, + struct stat *s) +{ + struct nios2_gdb_stat *p; + + p = lock_user(VERIFY_WRITE, addr, sizeof(struct nios2_gdb_stat), 0); + + if (!p) { + return false; + } + p->gdb_st_dev = cpu_to_be32(s->st_dev); + p->gdb_st_ino = cpu_to_be32(s->st_ino); + p->gdb_st_mode = cpu_to_be32(s->st_mode); + p->gdb_st_nlink = cpu_to_be32(s->st_nlink); + p->gdb_st_uid = cpu_to_be32(s->st_uid); + p->gdb_st_gid = cpu_to_be32(s->st_gid); + p->gdb_st_rdev = cpu_to_be32(s->st_rdev); + p->gdb_st_size = cpu_to_be64(s->st_size); +#ifdef _WIN32 + /* Windows stat is missing some fields. */ + p->gdb_st_blksize = 0; + p->gdb_st_blocks = 0; +#else + p->gdb_st_blksize = cpu_to_be64(s->st_blksize); + p->gdb_st_blocks = cpu_to_be64(s->st_blocks); +#endif + p->gdb_st_atime = cpu_to_be32(s->st_atime); + p->gdb_st_mtime = cpu_to_be32(s->st_mtime); + p->gdb_st_ctime = cpu_to_be32(s->st_ctime); + unlock_user(p, addr, sizeof(struct nios2_gdb_stat)); + return true; +} + +static void nios2_semi_return_u32(CPUNios2State *env, uint32_t ret, + uint32_t err) +{ + target_ulong args = env->regs[R_ARG1]; + if (put_user_u32(ret, args) || + put_user_u32(err, args + 4)) { + /* + * The nios2 semihosting ABI does not provide any way to report this + * error to the guest, so the best we can do is log it in qemu. + * It is always a guest error not to pass us a valid argument block. + */ + qemu_log_mask(LOG_GUEST_ERROR, "nios2-semihosting: return value " + "discarded because argument block not writable\n"); + } +} + +static void nios2_semi_return_u64(CPUNios2State *env, uint64_t ret, + uint32_t err) +{ + target_ulong args = env->regs[R_ARG1]; + if (put_user_u32(ret >> 32, args) || + put_user_u32(ret, args + 4) || + put_user_u32(err, args + 8)) { + /* No way to report this via nios2 semihosting ABI; just log it */ + qemu_log_mask(LOG_GUEST_ERROR, "nios2-semihosting: return value " + "discarded because argument block not writable\n"); + } +} + +static int nios2_semi_is_lseek; + +static void nios2_semi_cb(CPUState *cs, target_ulong ret, target_ulong err) +{ + Nios2CPU *cpu = NIOS2_CPU(cs); + CPUNios2State *env = &cpu->env; + + if (nios2_semi_is_lseek) { + /* + * FIXME: We've already lost the high bits of the lseek + * return value. + */ + nios2_semi_return_u64(env, ret, err); + nios2_semi_is_lseek = 0; + } else { + nios2_semi_return_u32(env, ret, err); + } +} + +/* + * Read the input value from the argument block; fail the semihosting + * call if the memory read fails. + */ +#define GET_ARG(n) do { \ + if (get_user_ual(arg ## n, args + (n) * 4)) { \ + result = -1; \ + errno = EFAULT; \ + goto failed; \ + } \ +} while (0) + +void do_nios2_semihosting(CPUNios2State *env) +{ + int nr; + uint32_t args; + target_ulong arg0, arg1, arg2, arg3; + void *p; + void *q; + uint32_t len; + uint32_t result; + + nr = env->regs[R_ARG0]; + args = env->regs[R_ARG1]; + switch (nr) { + case HOSTED_EXIT: + gdb_exit(env, env->regs[R_ARG0]); + exit(env->regs[R_ARG0]); + case HOSTED_OPEN: + GET_ARG(0); + GET_ARG(1); + GET_ARG(2); + GET_ARG(3); + if (use_gdb_syscalls()) { + gdb_do_syscall(nios2_semi_cb, "open,%s,%x,%x", arg0, (int)arg1, + arg2, arg3); + return; + } else { + p = lock_user_string(arg0); + if (!p) { + result = -1; + errno = EFAULT; + } else { + result = open(p, translate_openflags(arg2), arg3); + unlock_user(p, arg0, 0); + } + } + break; + case HOSTED_CLOSE: + { + /* Ignore attempts to close stdin/out/err. */ + GET_ARG(0); + int fd = arg0; + if (fd > 2) { + if (use_gdb_syscalls()) { + gdb_do_syscall(nios2_semi_cb, "close,%x", arg0); + return; + } else { + result = close(fd); + } + } else { + result = 0; + } + break; + } + case HOSTED_READ: + GET_ARG(0); + GET_ARG(1); + GET_ARG(2); + len = arg2; + if (use_gdb_syscalls()) { + gdb_do_syscall(nios2_semi_cb, "read,%x,%x,%x", + arg0, arg1, len); + return; + } else { + p = lock_user(VERIFY_WRITE, arg1, len, 0); + if (!p) { + result = -1; + errno = EFAULT; + } else { + result = read(arg0, p, len); + unlock_user(p, arg1, len); + } + } + break; + case HOSTED_WRITE: + GET_ARG(0); + GET_ARG(1); + GET_ARG(2); + len = arg2; + if (use_gdb_syscalls()) { + gdb_do_syscall(nios2_semi_cb, "write,%x,%x,%x", + arg0, arg1, len); + return; + } else { + p = lock_user(VERIFY_READ, arg1, len, 1); + if (!p) { + result = -1; + errno = EFAULT; + } else { + result = write(arg0, p, len); + unlock_user(p, arg0, 0); + } + } + break; + case HOSTED_LSEEK: + { + uint64_t off; + GET_ARG(0); + GET_ARG(1); + GET_ARG(2); + GET_ARG(3); + off = (uint32_t)arg2 | ((uint64_t)arg1 << 32); + if (use_gdb_syscalls()) { + nios2_semi_is_lseek = 1; + gdb_do_syscall(nios2_semi_cb, "lseek,%x,%lx,%x", + arg0, off, arg3); + } else { + off = lseek(arg0, off, arg3); + nios2_semi_return_u64(env, off, errno); + } + return; + } + case HOSTED_RENAME: + GET_ARG(0); + GET_ARG(1); + GET_ARG(2); + GET_ARG(3); + if (use_gdb_syscalls()) { + gdb_do_syscall(nios2_semi_cb, "rename,%s,%s", + arg0, (int)arg1, arg2, (int)arg3); + return; + } else { + p = lock_user_string(arg0); + q = lock_user_string(arg2); + if (!p || !q) { + result = -1; + errno = EFAULT; + } else { + result = rename(p, q); + } + unlock_user(p, arg0, 0); + unlock_user(q, arg2, 0); + } + break; + case HOSTED_UNLINK: + GET_ARG(0); + GET_ARG(1); + if (use_gdb_syscalls()) { + gdb_do_syscall(nios2_semi_cb, "unlink,%s", + arg0, (int)arg1); + return; + } else { + p = lock_user_string(arg0); + if (!p) { + result = -1; + errno = EFAULT; + } else { + result = unlink(p); + unlock_user(p, arg0, 0); + } + } + break; + case HOSTED_STAT: + GET_ARG(0); + GET_ARG(1); + GET_ARG(2); + if (use_gdb_syscalls()) { + gdb_do_syscall(nios2_semi_cb, "stat,%s,%x", + arg0, (int)arg1, arg2); + return; + } else { + struct stat s; + p = lock_user_string(arg0); + if (!p) { + result = -1; + errno = EFAULT; + } else { + result = stat(p, &s); + unlock_user(p, arg0, 0); + } + if (result == 0 && !translate_stat(env, arg2, &s)) { + result = -1; + errno = EFAULT; + } + } + break; + case HOSTED_FSTAT: + GET_ARG(0); + GET_ARG(1); + if (use_gdb_syscalls()) { + gdb_do_syscall(nios2_semi_cb, "fstat,%x,%x", + arg0, arg1); + return; + } else { + struct stat s; + result = fstat(arg0, &s); + if (result == 0 && !translate_stat(env, arg1, &s)) { + result = -1; + errno = EFAULT; + } + } + break; + case HOSTED_GETTIMEOFDAY: + /* Only the tv parameter is used. tz is assumed NULL. */ + GET_ARG(0); + if (use_gdb_syscalls()) { + gdb_do_syscall(nios2_semi_cb, "gettimeofday,%x,%x", + arg0, 0); + return; + } else { + qemu_timeval tv; + struct gdb_timeval *p; + result = qemu_gettimeofday(&tv); + if (result != 0) { + p = lock_user(VERIFY_WRITE, arg0, sizeof(struct gdb_timeval), + 0); + if (!p) { + result = -1; + errno = EFAULT; + } else { + p->tv_sec = cpu_to_be32(tv.tv_sec); + p->tv_usec = cpu_to_be64(tv.tv_usec); + unlock_user(p, arg0, sizeof(struct gdb_timeval)); + } + } + } + break; + case HOSTED_ISATTY: + GET_ARG(0); + if (use_gdb_syscalls()) { + gdb_do_syscall(nios2_semi_cb, "isatty,%x", arg0); + return; + } else { + result = isatty(arg0); + } + break; + case HOSTED_SYSTEM: + GET_ARG(0); + GET_ARG(1); + if (use_gdb_syscalls()) { + gdb_do_syscall(nios2_semi_cb, "system,%s", + arg0, (int)arg1); + return; + } else { + p = lock_user_string(arg0); + if (!p) { + result = -1; + errno = EFAULT; + } else { + result = system(p); + unlock_user(p, arg0, 0); + } + } + break; + default: + qemu_log_mask(LOG_GUEST_ERROR, "nios2-semihosting: unsupported " + "semihosting syscall %d\n", nr); + result = 0; + } +failed: + nios2_semi_return_u32(env, result, errno); +} |