@@ -2992,7 +2992,8 @@ STEXI
Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
ETEXI
DEF("semihosting", 0, QEMU_OPTION_semihosting,
- "-semihosting semihosting mode\n", QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA)
+ "-semihosting semihosting mode\n",
+ QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32)
STEXI
@item -semihosting
@findex -semihosting
@@ -1,3 +1,4 @@
obj-y += translate.o op_helper.o helper.o cpu.o
obj-y += gdbstub.o
+obj-y += lm32-semi.o
obj-$(CONFIG_SOFTMMU) += machine.o
@@ -26,6 +26,15 @@ first BSP which instantiate this model. A (32 bit) write to 0xfff0000
causes a vm shutdown.
+Semihosting
+-----------
+Semihosting on this target is supported. Some system calls like read, write
+and exit are executed on the host if semihosting is enabled. See
+target/lm32-semi.c for all supported system calls. Emulation aware programs
+can use this mechanism to shut down the virtual machine and print to the
+host console. See the tcg tests for an example.
+
+
Special instructions
--------------------
The translation recognizes one special instruction to halt the cpu:
@@ -14,5 +14,6 @@ DEF_HELPER_1(rcsr_ip, i32, env)
DEF_HELPER_1(rcsr_jtx, i32, env)
DEF_HELPER_1(rcsr_jrx, i32, env)
DEF_HELPER_1(ill, void, env)
+DEF_HELPER_1(semihosting, i32, env)
#include "exec/def-helper.h"
new file mode 100644
@@ -0,0 +1,212 @@
+/*
+ * Lattice Mico32 semihosting syscall interface
+ *
+ * Copyright (c) 2014 Michael Walle <michael@walle.cc>
+ *
+ * Based on target-m68k/m68k-semi.c, which is
+ * Copyright (c) 2005-2007 CodeSourcery.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include <errno.h>
+#include <unistd.h>
+#include <string.h>
+#include <stddef.h>
+#include "cpu.h"
+#include "helper.h"
+#include "qemu/log.h"
+#include "exec/softmmu-semi.h"
+
+enum {
+ TARGET_SYS_exit = 1,
+ TARGET_SYS_open = 2,
+ TARGET_SYS_close = 3,
+ TARGET_SYS_read = 4,
+ TARGET_SYS_write = 5,
+ TARGET_SYS_lseek = 6,
+ TARGET_SYS_fstat = 10,
+ TARGET_SYS_stat = 15,
+};
+
+enum {
+ NEWLIB_O_RDONLY = 0x0,
+ NEWLIB_O_WRONLY = 0x1,
+ NEWLIB_O_RDWR = 0x2,
+ NEWLIB_O_APPEND = 0x8,
+ NEWLIB_O_CREAT = 0x200,
+ NEWLIB_O_TRUNC = 0x400,
+ NEWLIB_O_EXCL = 0x800,
+};
+
+static int translate_openflags(int flags)
+{
+ int hf;
+
+ if (flags & NEWLIB_O_WRONLY) {
+ hf = O_WRONLY;
+ } else if (flags & NEWLIB_O_RDWR) {
+ hf = O_RDWR;
+ } else {
+ hf = O_RDONLY;
+ }
+
+ if (flags & NEWLIB_O_APPEND) {
+ hf |= O_APPEND;
+ }
+
+ if (flags & NEWLIB_O_CREAT) {
+ hf |= O_CREAT;
+ }
+
+ if (flags & NEWLIB_O_TRUNC) {
+ hf |= O_TRUNC;
+ }
+
+ if (flags & NEWLIB_O_EXCL) {
+ hf |= O_EXCL;
+ }
+
+ return hf;
+}
+
+struct newlib_stat {
+ int16_t newlib_st_dev; /* device */
+ uint16_t newlib_st_ino; /* inode */
+ uint16_t newlib_st_mode; /* protection */
+ uint16_t newlib_st_nlink; /* number of hard links */
+ uint16_t newlib_st_uid; /* user ID of owner */
+ uint16_t newlib_st_gid; /* group ID of owner */
+ int16_t newlib_st_rdev; /* device type (if inode device) */
+ int32_t newlib_st_size; /* total size, in bytes */
+ int32_t newlib_st_atime; /* time of last access */
+ uint32_t newlib_st_spare1;
+ int32_t newlib_st_mtime; /* time of last modification */
+ uint32_t newlib_st_spare2;
+ int32_t newlib_st_ctime; /* time of last change */
+ uint32_t newlib_st_spare3;
+} QEMU_PACKED;
+
+static int translate_stat(CPULM32State *env, target_ulong addr,
+ struct stat *s)
+{
+ struct newlib_stat *p;
+
+ p = lock_user(VERIFY_WRITE, addr, sizeof(struct newlib_stat), 0);
+ if (!p) {
+ return 0;
+ }
+ p->newlib_st_dev = cpu_to_be16(s->st_dev);
+ p->newlib_st_ino = cpu_to_be16(s->st_ino);
+ p->newlib_st_mode = cpu_to_be16(s->st_mode);
+ p->newlib_st_nlink = cpu_to_be16(s->st_nlink);
+ p->newlib_st_uid = cpu_to_be16(s->st_uid);
+ p->newlib_st_gid = cpu_to_be16(s->st_gid);
+ p->newlib_st_rdev = cpu_to_be16(s->st_rdev);
+ p->newlib_st_size = cpu_to_be32(s->st_size);
+ p->newlib_st_atime = cpu_to_be32(s->st_atime);
+ p->newlib_st_mtime = cpu_to_be32(s->st_mtime);
+ p->newlib_st_ctime = cpu_to_be32(s->st_ctime);
+ unlock_user(p, addr, sizeof(struct newlib_stat));
+
+ return 1;
+}
+
+uint32_t HELPER(semihosting)(CPULM32State *env)
+{
+ int ret = -1;
+ target_ulong nr, arg0, arg1, arg2;
+ void *p;
+ struct stat s;
+
+ nr = env->regs[R_R8];
+ arg0 = env->regs[R_R1];
+ arg1 = env->regs[R_R2];
+ arg2 = env->regs[R_R3];
+
+ switch (nr) {
+ case TARGET_SYS_exit:
+ /* void _exit(int rc) */
+ exit(arg0);
+
+ case TARGET_SYS_open:
+ /* int open(const char *pathname, int flags) */
+ p = lock_user_string(arg0);
+ if (!p) {
+ ret = -1;
+ } else {
+ ret = open(p, translate_openflags(arg2));
+ unlock_user(p, arg0, 0);
+ }
+ break;
+
+ case TARGET_SYS_read:
+ /* ssize_t read(int fd, const void *buf, size_t count) */
+ p = lock_user(VERIFY_WRITE, arg1, arg2, 0);
+ if (!p) {
+ ret = -1;
+ } else {
+ ret = read(arg0, p, arg2);
+ unlock_user(p, arg1, arg2);
+ }
+ break;
+
+ case TARGET_SYS_write:
+ /* ssize_t write(int fd, const void *buf, size_t count) */
+ p = lock_user(VERIFY_READ, arg1, arg2, 1);
+ if (!p) {
+ ret = -1;
+ } else {
+ ret = write(arg0, p, arg2);
+ unlock_user(p, arg1, 0);
+ }
+ break;
+
+ case TARGET_SYS_close:
+ /* int close(int fd) */
+ /* don't close stdin/stdout/stderr */
+ if (arg0 > 2) {
+ ret = close(arg0);
+ } else {
+ ret = 0;
+ }
+ break;
+
+ case TARGET_SYS_lseek:
+ /* off_t lseek(int fd, off_t offset, int whence */
+ ret = lseek(arg0, arg1, arg2);
+ break;
+
+ case TARGET_SYS_stat:
+ /* int stat(const char *path, struct stat *buf) */
+ p = lock_user_string(arg0);
+ if (!p) {
+ ret = -1;
+ } else {
+ ret = stat(p, &s);
+ unlock_user(p, arg0, 0);
+ if (translate_stat(env, arg1, &s) == 0) {
+ ret = -1;
+ }
+ }
+ break;
+
+ case TARGET_SYS_fstat:
+ /* int stat(int fd, struct stat *buf) */
+ ret = fstat(arg0, &s);
+ if (ret == 0) {
+ if (translate_stat(env, arg1, &s) == 0) {
+ ret = -1;
+ }
+ }
+ break;
+
+ default:
+ /* unhandled */
+ return 1;
+ }
+
+ env->regs[R_R1] = ret;
+ return 0;
+}
@@ -1,7 +1,7 @@
/*
* LatticeMico32 main translation routines.
*
- * Copyright (c) 2010 Michael Walle <michael@walle.cc>
+ * Copyright (c) 2010-2014 Michael Walle <michael@walle.cc>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
@@ -21,6 +21,7 @@
#include "disas/disas.h"
#include "helper.h"
#include "tcg-op.h"
+#include "sysemu/sysemu.h"
#include "hw/lm32/lm32_pic.h"
@@ -608,8 +609,20 @@ static void dec_scall(DisasContext *dc)
break;
case 7:
LOG_DIS("scall\n");
- tcg_gen_movi_tl(cpu_pc, dc->pc);
- t_gen_raise_exception(dc, EXCP_SYSTEMCALL);
+ if (unlikely(semihosting_enabled)) {
+ TCGv t0 = tcg_temp_new();
+ int l1 = gen_new_label();
+
+ gen_helper_semihosting(t0, cpu_env);
+ tcg_gen_brcondi_tl(TCG_COND_EQ, t0, 0, l1);
+ tcg_gen_movi_tl(cpu_pc, dc->pc);
+ t_gen_raise_exception(dc, EXCP_SYSTEMCALL);
+ gen_set_label(l1);
+ tcg_temp_free(t0);
+ } else {
+ tcg_gen_movi_tl(cpu_pc, dc->pc);
+ t_gen_raise_exception(dc, EXCP_SYSTEMCALL);
+ }
break;
default:
qemu_log_mask(LOG_GUEST_ERROR, "invalid opcode @0x%x", dc->pc);
Intercept certain system calls if semihosting is enabled. This should behave like the GDB simulator. Signed-off-by: Michael Walle <michael@walle.cc> --- qemu-options.hx | 3 +- target-lm32/Makefile.objs | 1 + target-lm32/README | 9 ++ target-lm32/helper.h | 1 + target-lm32/lm32-semi.c | 212 +++++++++++++++++++++++++++++++++++++++++++++ target-lm32/translate.c | 19 +++- 6 files changed, 241 insertions(+), 4 deletions(-) create mode 100644 target-lm32/lm32-semi.c