icount: Take iothread lock when running QEMU timers
[qemu/ar7.git] / semihosting / arm-compat-semi.c
blobe741674238f34da01755bbd48dda6cb7b51a6741
1 /*
2 * Semihosting support for systems modeled on the Arm "Angel"
3 * semihosting syscalls design. This includes Arm and RISC-V processors
5 * Copyright (c) 2005, 2007 CodeSourcery.
6 * Copyright (c) 2019 Linaro
7 * Written by Paul Brook.
9 * Copyright © 2020 by Keith Packard <keithp@keithp.com>
10 * Adapted for systems other than ARM, including RISC-V, by Keith Packard
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, see <http://www.gnu.org/licenses/>.
25 * ARM Semihosting is documented in:
26 * Semihosting for AArch32 and AArch64 Release 2.0
27 * https://static.docs.arm.com/100863/0200/semihosting.pdf
29 * RISC-V Semihosting is documented in:
30 * RISC-V Semihosting
31 * https://github.com/riscv/riscv-semihosting-spec/blob/main/riscv-semihosting-spec.adoc
34 #include "qemu/osdep.h"
35 #include "qemu/timer.h"
36 #include "exec/gdbstub.h"
37 #include "semihosting/semihost.h"
38 #include "semihosting/console.h"
39 #include "semihosting/common-semi.h"
40 #include "semihosting/guestfd.h"
41 #include "semihosting/syscalls.h"
43 #ifdef CONFIG_USER_ONLY
44 #include "qemu.h"
46 #define COMMON_SEMI_HEAP_SIZE (128 * 1024 * 1024)
47 #else
48 #include "qemu/cutils.h"
49 #include "hw/loader.h"
50 #include "hw/boards.h"
51 #endif
53 #define TARGET_SYS_OPEN 0x01
54 #define TARGET_SYS_CLOSE 0x02
55 #define TARGET_SYS_WRITEC 0x03
56 #define TARGET_SYS_WRITE0 0x04
57 #define TARGET_SYS_WRITE 0x05
58 #define TARGET_SYS_READ 0x06
59 #define TARGET_SYS_READC 0x07
60 #define TARGET_SYS_ISERROR 0x08
61 #define TARGET_SYS_ISTTY 0x09
62 #define TARGET_SYS_SEEK 0x0a
63 #define TARGET_SYS_FLEN 0x0c
64 #define TARGET_SYS_TMPNAM 0x0d
65 #define TARGET_SYS_REMOVE 0x0e
66 #define TARGET_SYS_RENAME 0x0f
67 #define TARGET_SYS_CLOCK 0x10
68 #define TARGET_SYS_TIME 0x11
69 #define TARGET_SYS_SYSTEM 0x12
70 #define TARGET_SYS_ERRNO 0x13
71 #define TARGET_SYS_GET_CMDLINE 0x15
72 #define TARGET_SYS_HEAPINFO 0x16
73 #define TARGET_SYS_EXIT 0x18
74 #define TARGET_SYS_SYNCCACHE 0x19
75 #define TARGET_SYS_EXIT_EXTENDED 0x20
76 #define TARGET_SYS_ELAPSED 0x30
77 #define TARGET_SYS_TICKFREQ 0x31
79 /* ADP_Stopped_ApplicationExit is used for exit(0),
80 * anything else is implemented as exit(1) */
81 #define ADP_Stopped_ApplicationExit (0x20026)
83 #ifndef O_BINARY
84 #define O_BINARY 0
85 #endif
87 static int gdb_open_modeflags[12] = {
88 GDB_O_RDONLY,
89 GDB_O_RDONLY,
90 GDB_O_RDWR,
91 GDB_O_RDWR,
92 GDB_O_WRONLY | GDB_O_CREAT | GDB_O_TRUNC,
93 GDB_O_WRONLY | GDB_O_CREAT | GDB_O_TRUNC,
94 GDB_O_RDWR | GDB_O_CREAT | GDB_O_TRUNC,
95 GDB_O_RDWR | GDB_O_CREAT | GDB_O_TRUNC,
96 GDB_O_WRONLY | GDB_O_CREAT | GDB_O_APPEND,
97 GDB_O_WRONLY | GDB_O_CREAT | GDB_O_APPEND,
98 GDB_O_RDWR | GDB_O_CREAT | GDB_O_APPEND,
99 GDB_O_RDWR | GDB_O_CREAT | GDB_O_APPEND,
102 #ifndef CONFIG_USER_ONLY
105 * common_semi_find_bases: find information about ram and heap base
107 * This function attempts to provide meaningful numbers for RAM and
108 * HEAP base addresses. The rambase is simply the lowest addressable
109 * RAM position. For the heapbase we ask the loader to scan the
110 * address space and the largest available gap by querying the "ROM"
111 * regions.
113 * Returns: a structure with the numbers we need.
116 typedef struct LayoutInfo {
117 target_ulong rambase;
118 size_t ramsize;
119 hwaddr heapbase;
120 hwaddr heaplimit;
121 } LayoutInfo;
123 static bool find_ram_cb(Int128 start, Int128 len, const MemoryRegion *mr,
124 hwaddr offset_in_region, void *opaque)
126 LayoutInfo *info = (LayoutInfo *) opaque;
127 uint64_t size = int128_get64(len);
129 if (!mr->ram || mr->readonly) {
130 return false;
133 if (size > info->ramsize) {
134 info->rambase = int128_get64(start);
135 info->ramsize = size;
138 /* search exhaustively for largest RAM */
139 return false;
142 static LayoutInfo common_semi_find_bases(CPUState *cs)
144 FlatView *fv;
145 LayoutInfo info = { 0, 0, 0, 0 };
147 RCU_READ_LOCK_GUARD();
149 fv = address_space_to_flatview(cs->as);
150 flatview_for_each_range(fv, find_ram_cb, &info);
153 * If we have found the RAM lets iterate through the ROM blobs to
154 * work out the best place for the remainder of RAM and split it
155 * equally between stack and heap.
157 if (info.rambase || info.ramsize > 0) {
158 RomGap gap = rom_find_largest_gap_between(info.rambase, info.ramsize);
159 info.heapbase = gap.base;
160 info.heaplimit = gap.base + gap.size;
163 return info;
166 #endif
168 #include "common-semi-target.h"
171 * Read the input value from the argument block; fail the semihosting
172 * call if the memory read fails. Eventually we could use a generic
173 * CPUState helper function here.
174 * Note that GET_ARG() handles memory access errors by jumping to
175 * do_fault, so must be used as the first thing done in handling a
176 * semihosting call, to avoid accidentally leaking allocated resources.
177 * SET_ARG(), since it unavoidably happens late, instead returns an
178 * error indication (0 on success, non-0 for error) which the caller
179 * should check.
182 #define GET_ARG(n) do { \
183 if (is_64bit_semihosting(env)) { \
184 if (get_user_u64(arg ## n, args + (n) * 8)) { \
185 goto do_fault; \
187 } else { \
188 if (get_user_u32(arg ## n, args + (n) * 4)) { \
189 goto do_fault; \
192 } while (0)
194 #define SET_ARG(n, val) \
195 (is_64bit_semihosting(env) ? \
196 put_user_u64(val, args + (n) * 8) : \
197 put_user_u32(val, args + (n) * 4))
201 * The semihosting API has no concept of its errno being thread-safe,
202 * as the API design predates SMP CPUs and was intended as a simple
203 * real-hardware set of debug functionality. For QEMU, we make the
204 * errno be per-thread in linux-user mode; in softmmu it is a simple
205 * global, and we assume that the guest takes care of avoiding any races.
207 #ifndef CONFIG_USER_ONLY
208 static target_ulong syscall_err;
210 #include "semihosting/softmmu-uaccess.h"
211 #endif
213 static inline uint32_t get_swi_errno(CPUState *cs)
215 #ifdef CONFIG_USER_ONLY
216 TaskState *ts = cs->opaque;
218 return ts->swi_errno;
219 #else
220 return syscall_err;
221 #endif
224 static void common_semi_cb(CPUState *cs, uint64_t ret, int err)
226 if (err) {
227 #ifdef CONFIG_USER_ONLY
228 TaskState *ts = cs->opaque;
229 ts->swi_errno = err;
230 #else
231 syscall_err = err;
232 #endif
234 common_semi_set_ret(cs, ret);
238 * Use 0xdeadbeef as the return value when there isn't a defined
239 * return value for the call.
241 static void common_semi_dead_cb(CPUState *cs, uint64_t ret, int err)
243 common_semi_set_ret(cs, 0xdeadbeef);
247 * SYS_READ and SYS_WRITE always return the number of bytes not read/written.
248 * There is no error condition, other than returning the original length.
250 static void common_semi_rw_cb(CPUState *cs, uint64_t ret, int err)
252 /* Recover the original length from the third argument. */
253 CPUArchState *env G_GNUC_UNUSED = cs->env_ptr;
254 target_ulong args = common_semi_arg(cs, 1);
255 target_ulong arg2;
256 GET_ARG(2);
258 if (err) {
259 do_fault:
260 ret = 0; /* error: no bytes transmitted */
262 common_semi_set_ret(cs, arg2 - ret);
266 * Convert from Posix ret+errno to Arm SYS_ISTTY return values.
267 * With gdbstub, err is only ever set for protocol errors to EIO.
269 static void common_semi_istty_cb(CPUState *cs, uint64_t ret, int err)
271 if (err) {
272 ret = (err == ENOTTY ? 0 : -1);
274 common_semi_cb(cs, ret, err);
278 * SYS_SEEK returns 0 on success, not the resulting offset.
280 static void common_semi_seek_cb(CPUState *cs, uint64_t ret, int err)
282 if (!err) {
283 ret = 0;
285 common_semi_cb(cs, ret, err);
289 * Return an address in target memory of 64 bytes where the remote
290 * gdb should write its stat struct. (The format of this structure
291 * is defined by GDB's remote protocol and is not target-specific.)
292 * We put this on the guest's stack just below SP.
294 static target_ulong common_semi_flen_buf(CPUState *cs)
296 target_ulong sp = common_semi_stack_bottom(cs);
297 return sp - 64;
300 static void
301 common_semi_flen_fstat_cb(CPUState *cs, uint64_t ret, int err)
303 if (!err) {
304 /* The size is always stored in big-endian order, extract the value. */
305 uint64_t size;
306 if (cpu_memory_rw_debug(cs, common_semi_flen_buf(cs) +
307 offsetof(struct gdb_stat, gdb_st_size),
308 &size, 8, 0)) {
309 ret = -1, err = EFAULT;
310 } else {
311 size = be64_to_cpu(size);
312 if (ret != size) {
313 ret = -1, err = EOVERFLOW;
317 common_semi_cb(cs, ret, err);
320 static void
321 common_semi_readc_cb(CPUState *cs, uint64_t ret, int err)
323 if (!err) {
324 CPUArchState *env G_GNUC_UNUSED = cs->env_ptr;
325 uint8_t ch;
327 if (get_user_u8(ch, common_semi_stack_bottom(cs) - 1)) {
328 ret = -1, err = EFAULT;
329 } else {
330 ret = ch;
333 common_semi_cb(cs, ret, err);
336 #define SHFB_MAGIC_0 0x53
337 #define SHFB_MAGIC_1 0x48
338 #define SHFB_MAGIC_2 0x46
339 #define SHFB_MAGIC_3 0x42
341 /* Feature bits reportable in feature byte 0 */
342 #define SH_EXT_EXIT_EXTENDED (1 << 0)
343 #define SH_EXT_STDOUT_STDERR (1 << 1)
345 static const uint8_t featurefile_data[] = {
346 SHFB_MAGIC_0,
347 SHFB_MAGIC_1,
348 SHFB_MAGIC_2,
349 SHFB_MAGIC_3,
350 SH_EXT_EXIT_EXTENDED | SH_EXT_STDOUT_STDERR, /* Feature byte 0 */
354 * Do a semihosting call.
356 * The specification always says that the "return register" either
357 * returns a specific value or is corrupted, so we don't need to
358 * report to our caller whether we are returning a value or trying to
359 * leave the register unchanged.
361 void do_common_semihosting(CPUState *cs)
363 CPUArchState *env = cs->env_ptr;
364 target_ulong args;
365 target_ulong arg0, arg1, arg2, arg3;
366 target_ulong ul_ret;
367 char * s;
368 int nr;
369 uint32_t ret;
370 int64_t elapsed;
372 nr = common_semi_arg(cs, 0) & 0xffffffffU;
373 args = common_semi_arg(cs, 1);
375 switch (nr) {
376 case TARGET_SYS_OPEN:
378 int ret, err = 0;
379 int hostfd;
381 GET_ARG(0);
382 GET_ARG(1);
383 GET_ARG(2);
384 s = lock_user_string(arg0);
385 if (!s) {
386 goto do_fault;
388 if (arg1 >= 12) {
389 unlock_user(s, arg0, 0);
390 common_semi_cb(cs, -1, EINVAL);
391 break;
394 if (strcmp(s, ":tt") == 0) {
396 * We implement SH_EXT_STDOUT_STDERR, so:
397 * open for read == stdin
398 * open for write == stdout
399 * open for append == stderr
401 if (arg1 < 4) {
402 hostfd = STDIN_FILENO;
403 } else if (arg1 < 8) {
404 hostfd = STDOUT_FILENO;
405 } else {
406 hostfd = STDERR_FILENO;
408 ret = alloc_guestfd();
409 associate_guestfd(ret, hostfd);
410 } else if (strcmp(s, ":semihosting-features") == 0) {
411 /* We must fail opens for modes other than 0 ('r') or 1 ('rb') */
412 if (arg1 != 0 && arg1 != 1) {
413 ret = -1;
414 err = EACCES;
415 } else {
416 ret = alloc_guestfd();
417 staticfile_guestfd(ret, featurefile_data,
418 sizeof(featurefile_data));
420 } else {
421 unlock_user(s, arg0, 0);
422 semihost_sys_open(cs, common_semi_cb, arg0, arg2 + 1,
423 gdb_open_modeflags[arg1], 0644);
424 break;
426 unlock_user(s, arg0, 0);
427 common_semi_cb(cs, ret, err);
428 break;
431 case TARGET_SYS_CLOSE:
432 GET_ARG(0);
433 semihost_sys_close(cs, common_semi_cb, arg0);
434 break;
436 case TARGET_SYS_WRITEC:
438 * FIXME: the byte to be written is in a target_ulong slot,
439 * which means this is wrong for a big-endian guest.
441 semihost_sys_write_gf(cs, common_semi_dead_cb,
442 &console_out_gf, args, 1);
443 break;
445 case TARGET_SYS_WRITE0:
447 ssize_t len = target_strlen(args);
448 if (len < 0) {
449 common_semi_dead_cb(cs, -1, EFAULT);
450 } else {
451 semihost_sys_write_gf(cs, common_semi_dead_cb,
452 &console_out_gf, args, len);
455 break;
457 case TARGET_SYS_WRITE:
458 GET_ARG(0);
459 GET_ARG(1);
460 GET_ARG(2);
461 semihost_sys_write(cs, common_semi_rw_cb, arg0, arg1, arg2);
462 break;
464 case TARGET_SYS_READ:
465 GET_ARG(0);
466 GET_ARG(1);
467 GET_ARG(2);
468 semihost_sys_read(cs, common_semi_rw_cb, arg0, arg1, arg2);
469 break;
471 case TARGET_SYS_READC:
472 semihost_sys_read_gf(cs, common_semi_readc_cb, &console_in_gf,
473 common_semi_stack_bottom(cs) - 1, 1);
474 break;
476 case TARGET_SYS_ISERROR:
477 GET_ARG(0);
478 common_semi_set_ret(cs, (target_long)arg0 < 0);
479 break;
481 case TARGET_SYS_ISTTY:
482 GET_ARG(0);
483 semihost_sys_isatty(cs, common_semi_istty_cb, arg0);
484 break;
486 case TARGET_SYS_SEEK:
487 GET_ARG(0);
488 GET_ARG(1);
489 semihost_sys_lseek(cs, common_semi_seek_cb, arg0, arg1, GDB_SEEK_SET);
490 break;
492 case TARGET_SYS_FLEN:
493 GET_ARG(0);
494 semihost_sys_flen(cs, common_semi_flen_fstat_cb, common_semi_cb,
495 arg0, common_semi_flen_buf(cs));
496 break;
498 case TARGET_SYS_TMPNAM:
500 int len;
501 char *p;
503 GET_ARG(0);
504 GET_ARG(1);
505 GET_ARG(2);
506 len = asprintf(&s, "/tmp/qemu-%x%02x", getpid(), (int)arg1 & 0xff);
507 if (len < 0) {
508 common_semi_set_ret(cs, -1);
509 break;
512 /* Allow for trailing NUL */
513 len++;
514 /* Make sure there's enough space in the buffer */
515 if (len > arg2) {
516 free(s);
517 common_semi_set_ret(cs, -1);
518 break;
520 p = lock_user(VERIFY_WRITE, arg0, len, 0);
521 if (!p) {
522 free(s);
523 goto do_fault;
525 memcpy(p, s, len);
526 unlock_user(p, arg0, len);
527 free(s);
528 common_semi_set_ret(cs, 0);
529 break;
532 case TARGET_SYS_REMOVE:
533 GET_ARG(0);
534 GET_ARG(1);
535 semihost_sys_remove(cs, common_semi_cb, arg0, arg1 + 1);
536 break;
538 case TARGET_SYS_RENAME:
539 GET_ARG(0);
540 GET_ARG(1);
541 GET_ARG(2);
542 GET_ARG(3);
543 semihost_sys_rename(cs, common_semi_cb, arg0, arg1 + 1, arg2, arg3 + 1);
544 break;
546 case TARGET_SYS_CLOCK:
547 common_semi_set_ret(cs, clock() / (CLOCKS_PER_SEC / 100));
548 break;
550 case TARGET_SYS_TIME:
551 ul_ret = time(NULL);
552 common_semi_cb(cs, ul_ret, ul_ret == -1 ? errno : 0);
553 break;
555 case TARGET_SYS_SYSTEM:
556 GET_ARG(0);
557 GET_ARG(1);
558 semihost_sys_system(cs, common_semi_cb, arg0, arg1 + 1);
559 break;
561 case TARGET_SYS_ERRNO:
562 common_semi_set_ret(cs, get_swi_errno(cs));
563 break;
565 case TARGET_SYS_GET_CMDLINE:
567 /* Build a command-line from the original argv.
569 * The inputs are:
570 * * arg0, pointer to a buffer of at least the size
571 * specified in arg1.
572 * * arg1, size of the buffer pointed to by arg0 in
573 * bytes.
575 * The outputs are:
576 * * arg0, pointer to null-terminated string of the
577 * command line.
578 * * arg1, length of the string pointed to by arg0.
581 char *output_buffer;
582 size_t input_size;
583 size_t output_size;
584 int status = 0;
585 #if !defined(CONFIG_USER_ONLY)
586 const char *cmdline;
587 #else
588 TaskState *ts = cs->opaque;
589 #endif
590 GET_ARG(0);
591 GET_ARG(1);
592 input_size = arg1;
593 /* Compute the size of the output string. */
594 #if !defined(CONFIG_USER_ONLY)
595 cmdline = semihosting_get_cmdline();
596 if (cmdline == NULL) {
597 cmdline = ""; /* Default to an empty line. */
599 output_size = strlen(cmdline) + 1; /* Count terminating 0. */
600 #else
601 unsigned int i;
603 output_size = ts->info->env_strings - ts->info->arg_strings;
604 if (!output_size) {
606 * We special-case the "empty command line" case (argc==0).
607 * Just provide the terminating 0.
609 output_size = 1;
611 #endif
613 if (output_size > input_size) {
614 /* Not enough space to store command-line arguments. */
615 common_semi_cb(cs, -1, E2BIG);
616 break;
619 /* Adjust the command-line length. */
620 if (SET_ARG(1, output_size - 1)) {
621 /* Couldn't write back to argument block */
622 goto do_fault;
625 /* Lock the buffer on the ARM side. */
626 output_buffer = lock_user(VERIFY_WRITE, arg0, output_size, 0);
627 if (!output_buffer) {
628 goto do_fault;
631 /* Copy the command-line arguments. */
632 #if !defined(CONFIG_USER_ONLY)
633 pstrcpy(output_buffer, output_size, cmdline);
634 #else
635 if (output_size == 1) {
636 /* Empty command-line. */
637 output_buffer[0] = '\0';
638 goto out;
641 if (copy_from_user(output_buffer, ts->info->arg_strings,
642 output_size)) {
643 unlock_user(output_buffer, arg0, 0);
644 goto do_fault;
647 /* Separate arguments by white spaces. */
648 for (i = 0; i < output_size - 1; i++) {
649 if (output_buffer[i] == 0) {
650 output_buffer[i] = ' ';
653 out:
654 #endif
655 /* Unlock the buffer on the ARM side. */
656 unlock_user(output_buffer, arg0, output_size);
657 common_semi_cb(cs, status, 0);
659 break;
661 case TARGET_SYS_HEAPINFO:
663 target_ulong retvals[4];
664 int i;
665 #ifdef CONFIG_USER_ONLY
666 TaskState *ts = cs->opaque;
667 target_ulong limit;
668 #else
669 LayoutInfo info = common_semi_find_bases(cs);
670 #endif
672 GET_ARG(0);
674 #ifdef CONFIG_USER_ONLY
676 * Some C libraries assume the heap immediately follows .bss, so
677 * allocate it using sbrk.
679 if (!ts->heap_limit) {
680 abi_ulong ret;
682 ts->heap_base = do_brk(0);
683 limit = ts->heap_base + COMMON_SEMI_HEAP_SIZE;
684 /* Try a big heap, and reduce the size if that fails. */
685 for (;;) {
686 ret = do_brk(limit);
687 if (ret >= limit) {
688 break;
690 limit = (ts->heap_base >> 1) + (limit >> 1);
692 ts->heap_limit = limit;
695 retvals[0] = ts->heap_base;
696 retvals[1] = ts->heap_limit;
697 retvals[2] = ts->stack_base;
698 retvals[3] = 0; /* Stack limit. */
699 #else
700 retvals[0] = info.heapbase; /* Heap Base */
701 retvals[1] = info.heaplimit; /* Heap Limit */
702 retvals[2] = info.heaplimit; /* Stack base */
703 retvals[3] = info.heapbase; /* Stack limit. */
704 #endif
706 for (i = 0; i < ARRAY_SIZE(retvals); i++) {
707 bool fail;
709 if (is_64bit_semihosting(env)) {
710 fail = put_user_u64(retvals[i], arg0 + i * 8);
711 } else {
712 fail = put_user_u32(retvals[i], arg0 + i * 4);
715 if (fail) {
716 /* Couldn't write back to argument block */
717 goto do_fault;
720 common_semi_set_ret(cs, 0);
722 break;
724 case TARGET_SYS_EXIT:
725 case TARGET_SYS_EXIT_EXTENDED:
726 if (common_semi_sys_exit_extended(cs, nr)) {
728 * The A64 version of SYS_EXIT takes a parameter block,
729 * so the application-exit type can return a subcode which
730 * is the exit status code from the application.
731 * SYS_EXIT_EXTENDED is an a new-in-v2.0 optional function
732 * which allows A32/T32 guests to also provide a status code.
734 GET_ARG(0);
735 GET_ARG(1);
737 if (arg0 == ADP_Stopped_ApplicationExit) {
738 ret = arg1;
739 } else {
740 ret = 1;
742 } else {
744 * The A32/T32 version of SYS_EXIT specifies only
745 * Stopped_ApplicationExit as normal exit, but does not
746 * allow the guest to specify the exit status code.
747 * Everything else is considered an error.
749 ret = (args == ADP_Stopped_ApplicationExit) ? 0 : 1;
751 gdb_exit(ret);
752 exit(ret);
754 case TARGET_SYS_ELAPSED:
755 elapsed = get_clock() - clock_start;
756 if (sizeof(target_ulong) == 8) {
757 if (SET_ARG(0, elapsed)) {
758 goto do_fault;
760 } else {
761 if (SET_ARG(0, (uint32_t) elapsed) ||
762 SET_ARG(1, (uint32_t) (elapsed >> 32))) {
763 goto do_fault;
766 common_semi_set_ret(cs, 0);
767 break;
769 case TARGET_SYS_TICKFREQ:
770 /* qemu always uses nsec */
771 common_semi_set_ret(cs, 1000000000);
772 break;
774 case TARGET_SYS_SYNCCACHE:
776 * Clean the D-cache and invalidate the I-cache for the specified
777 * virtual address range. This is a nop for us since we don't
778 * implement caches. This is only present on A64.
780 if (common_semi_has_synccache(env)) {
781 common_semi_set_ret(cs, 0);
782 break;
784 /* fall through */
785 default:
786 fprintf(stderr, "qemu: Unsupported SemiHosting SWI 0x%02x\n", nr);
787 cpu_dump_state(cs, stderr, 0);
788 abort();
790 do_fault:
791 common_semi_cb(cs, -1, EFAULT);
792 break;