* Copyright (C) 2009 by Marvell Technology Group Ltd. *
* Written by Nicolas Pitre <nico@marvell.com> *
* *
+ * Copyright (C) 2010 by Spencer Oliver *
+ * spen@spen-soft.co.uk *
+ * *
+ * Copyright (C) 2016 by Square, Inc. *
+ * Steven Stallion <stallion@squareup.com> *
+ * *
+ * Copyright (C) 2018 by Liviu Ionescu *
+ * <ilg@livius.net> *
+ * *
* 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 *
* 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, write to the *
- * Free Software Foundation, Inc., *
- * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
+ * along with this program. If not, see <http://www.gnu.org/licenses/>. *
***************************************************************************/
/**
#include "config.h"
#endif
+#include "arm.h"
#include "armv4_5.h"
+#include "arm7_9_common.h"
+#include "armv7m.h"
+#include "armv7a.h"
+#include "armv8.h"
+#include "cortex_m.h"
#include "register.h"
+#include "arm_opcodes.h"
+#include "target_type.h"
#include "arm_semihosting.h"
#include <helper/binarybuffer.h>
#include <helper/log.h>
+#include <sys/stat.h>
-/* TODO: this needs to be per target */
-int semihosting_active;
-int semihosting_errno;
-
-static int do_semihosting(struct target *target)
+static int arm_semihosting_resume(struct target *target, int *retval)
{
- struct arm *armv4_5 = target_to_armv4_5(target);
- uint32_t r0 = buf_get_u32(armv4_5->core_cache->reg_list[0].value, 0, 32);
- uint32_t r1 = buf_get_u32(armv4_5->core_cache->reg_list[1].value, 0, 32);
- uint32_t lr = buf_get_u32(ARMV4_5_CORE_REG_MODE(armv4_5->core_cache, ARMV4_5_MODE_SVC, 14).value, 0, 32);
- uint32_t spsr = buf_get_u32(armv4_5->spsr->value, 0, 32);;
- uint8_t params[16];
- int retval, result;
-
- /*
- * TODO: lots of security issues are not considered yet, such as:
- * - no validation on target provided file descriptors
- * - no safety checks on opened/deleted/renamed file paths
- * Beware the target app you use this support with.
- */
- switch (r0) {
- case 0x01: /* SYS_OPEN */
- retval = target_read_memory(target, r1, 4, 3, params);
- if (retval != ERROR_OK)
- return retval;
- else {
- uint32_t a = target_buffer_get_u32(target, params+0);
- uint32_t m = target_buffer_get_u32(target, params+4);
- uint32_t l = target_buffer_get_u32(target, params+8);
- if (l <= 255 && m <= 11) {
- uint8_t fn[256];
- int mode;
- retval = target_read_memory(target, a, 1, l, fn);
- if (retval != ERROR_OK)
- return retval;
- fn[l] = 0;
- if (m & 0x2)
- mode = O_RDWR;
- else if (m & 0xc)
- mode = O_WRONLY;
- else
- mode = O_RDONLY;
- if (m >= 8)
- mode |= O_CREAT|O_APPEND;
- else if (m >= 4)
- mode |= O_CREAT|O_TRUNC;
- if (strcmp((char *)fn, ":tt") == 0) {
- if ((mode & 3) == 0)
- result = dup(0);
- else
- result = dup(1);
- } else
- result = open((char *)fn, mode);
- semihosting_errno = errno;
- } else {
- result = -1;
- semihosting_errno = EINVAL;
- }
- }
- break;
-
- case 0x02: /* SYS_CLOSE */
- retval = target_read_memory(target, r1, 4, 1, params);
- if (retval != ERROR_OK)
- return retval;
- else {
- int fd = target_buffer_get_u32(target, params+0);
- result = close(fd);
- semihosting_errno = errno;
- }
- break;
-
- case 0x03: /* SYS_WRITEC */
- {
- unsigned char c;
- retval = target_read_memory(target, r1, 1, 1, &c);
- if (retval != ERROR_OK)
- return retval;
- putchar(c);
- result = 0;
- }
- break;
-
- case 0x04: /* SYS_WRITE0 */
- do {
- unsigned char c;
- retval = target_read_memory(target, r1, 1, 1, &c);
- if (retval != ERROR_OK)
- return retval;
- if (!c)
- break;
- putchar(c);
- } while (1);
- result = 0;
- break;
-
- case 0x05: /* SYS_WRITE */
- retval = target_read_memory(target, r1, 4, 3, params);
- if (retval != ERROR_OK)
- return retval;
- else {
- int fd = target_buffer_get_u32(target, params+0);
- uint32_t a = target_buffer_get_u32(target, params+4);
- size_t l = target_buffer_get_u32(target, params+8);
- uint8_t *buf = malloc(l);
- if (!buf) {
- result = -1;
- semihosting_errno = ENOMEM;
- } else {
- retval = target_read_buffer(target, a, l, buf);
- if (retval != ERROR_OK) {
- free(buf);
- return retval;
- }
- result = write(fd, buf, l);
- semihosting_errno = errno;
- if (result >= 0)
- result = l - result;
- free(buf);
- }
- }
- break;
-
- case 0x06: /* SYS_READ */
- retval = target_read_memory(target, r1, 4, 3, params);
- if (retval != ERROR_OK)
- return retval;
- else {
- int fd = target_buffer_get_u32(target, params+0);
- uint32_t a = target_buffer_get_u32(target, params+4);
- ssize_t l = target_buffer_get_u32(target, params+8);
- uint8_t *buf = malloc(l);
- if (!buf) {
- result = -1;
- semihosting_errno = ENOMEM;
- } else {
- result = read(fd, buf, l);
- semihosting_errno = errno;
- if (result > 0) {
- retval = target_write_buffer(target, a, result, buf);
- if (retval != ERROR_OK) {
- free(buf);
- return retval;
- }
- result = l - result;
- }
- free(buf);
- }
- }
- break;
-
- case 0x07: /* SYS_READC */
- result = getchar();
- break;
-
- case 0x08: /* SYS_ISERROR */
- retval = target_read_memory(target, r1, 4, 1, params);
- if (retval != ERROR_OK)
- return retval;
- result = (target_buffer_get_u32(target, params+0) != 0);
- break;
-
- case 0x09: /* SYS_ISTTY */
- retval = target_read_memory(target, r1, 4, 1, params);
- if (retval != ERROR_OK)
- return retval;
- result = isatty(target_buffer_get_u32(target, params+0));
- break;
-
- case 0x0a: /* SYS_SEEK */
- retval = target_read_memory(target, r1, 4, 2, params);
- if (retval != ERROR_OK)
- return retval;
- else {
- int fd = target_buffer_get_u32(target, params+0);
- off_t pos = target_buffer_get_u32(target, params+4);
- result = lseek(fd, pos, SEEK_SET);
- semihosting_errno = errno;
- if (result == pos)
- result = 0;
- }
- break;
-
- case 0x0c: /* SYS_FLEN */
- retval = target_read_memory(target, r1, 4, 1, params);
- if (retval != ERROR_OK)
- return retval;
- else {
- int fd = target_buffer_get_u32(target, params+0);
- off_t cur = lseek(fd, 0, SEEK_CUR);
- if (cur == (off_t)-1) {
- semihosting_errno = errno;
- result = -1;
- break;
- }
- result = lseek(fd, 0, SEEK_END);
- semihosting_errno = errno;
- if (lseek(fd, cur, SEEK_SET) == (off_t)-1) {
- semihosting_errno = errno;
- result = -1;
- }
- }
- break;
-
- case 0x0e: /* SYS_REMOVE */
- retval = target_read_memory(target, r1, 4, 2, params);
- if (retval != ERROR_OK)
- return retval;
- else {
- uint32_t a = target_buffer_get_u32(target, params+0);
- uint32_t l = target_buffer_get_u32(target, params+4);
- if (l <= 255) {
- uint8_t fn[256];
- retval = target_read_memory(target, a, 1, l, fn);
- if (retval != ERROR_OK)
- return retval;
- fn[l] = 0;
- result = remove((char *)fn);
- semihosting_errno = errno;
- } else {
- result = -1;
- semihosting_errno = EINVAL;
- }
- }
- break;
-
- case 0x0f: /* SYS_RENAME */
- retval = target_read_memory(target, r1, 4, 4, params);
- if (retval != ERROR_OK)
- return retval;
- else {
- uint32_t a1 = target_buffer_get_u32(target, params+0);
- uint32_t l1 = target_buffer_get_u32(target, params+4);
- uint32_t a2 = target_buffer_get_u32(target, params+8);
- uint32_t l2 = target_buffer_get_u32(target, params+12);
- if (l1 <= 255 && l2 <= 255) {
- uint8_t fn1[256], fn2[256];
- retval = target_read_memory(target, a1, 1, l1, fn1);
- if (retval != ERROR_OK)
- return retval;
- retval = target_read_memory(target, a2, 1, l2, fn2);
- if (retval != ERROR_OK)
- return retval;
- fn1[l1] = 0;
- fn2[l2] = 0;
- result = rename((char *)fn1, (char *)fn2);
- semihosting_errno = errno;
- } else {
- result = -1;
- semihosting_errno = EINVAL;
- }
- }
- break;
-
- case 0x11: /* SYS_TIME */
- result = time(NULL);
- break;
-
- case 0x13: /* SYS_ERRNO */
- result = semihosting_errno;
- break;
-
- case 0x15: /* SYS_GET_CMDLINE */
- retval = target_read_memory(target, r1, 4, 2, params);
- if (retval != ERROR_OK)
- return retval;
- else {
- uint32_t a = target_buffer_get_u32(target, params+0);
- uint32_t l = target_buffer_get_u32(target, params+4);
- char *arg = "foobar";
- uint32_t s = strlen(arg) + 1;
- if (l < s)
- result = -1;
- else {
- retval = target_write_buffer(target, a, s, (void*)arg);
- if (retval != ERROR_OK)
- return retval;
- result = 0;
+ if (is_armv8(target_to_armv8(target))) {
+ struct armv8_common *armv8 = target_to_armv8(target);
+ if (armv8->last_run_control_op == ARMV8_RUNCONTROL_RESUME) {
+ *retval = target_resume(target, 1, 0, 0, 0);
+ if (*retval != ERROR_OK) {
+ LOG_ERROR("Failed to resume target");
+ return 0;
}
+ } else if (armv8->last_run_control_op == ARMV8_RUNCONTROL_STEP)
+ target->debug_reason = DBG_REASON_SINGLESTEP;
+ } else {
+ *retval = target_resume(target, 1, 0, 0, 0);
+ if (*retval != ERROR_OK) {
+ LOG_ERROR("Failed to resume target");
+ return 0;
}
- break;
-
- case 0x16: /* SYS_HEAPINFO */
- retval = target_read_memory(target, r1, 4, 1, params);
- if (retval != ERROR_OK)
- return retval;
- else {
- uint32_t a = target_buffer_get_u32(target, params+0);
- /* tell the remote we have no idea */
- memset(params, 0, 4*4);
- retval = target_write_memory(target, a, 4, 4, params);
- if (retval != ERROR_OK)
- return retval;
- result = 0;
- }
- break;
-
- case 0x18: /* angel_SWIreason_ReportException */
- switch (r1) {
- case 0x20026: /* ADP_Stopped_ApplicationExit */
- fprintf(stderr, "semihosting: *** application exited ***\n");
- break;
- case 0x20000: /* ADP_Stopped_BranchThroughZero */
- case 0x20001: /* ADP_Stopped_UndefinedInstr */
- case 0x20002: /* ADP_Stopped_SoftwareInterrupt */
- case 0x20003: /* ADP_Stopped_PrefetchAbort */
- case 0x20004: /* ADP_Stopped_DataAbort */
- case 0x20005: /* ADP_Stopped_AddressException */
- case 0x20006: /* ADP_Stopped_IRQ */
- case 0x20007: /* ADP_Stopped_FIQ */
- case 0x20020: /* ADP_Stopped_BreakPoint */
- case 0x20021: /* ADP_Stopped_WatchPoint */
- case 0x20022: /* ADP_Stopped_StepComplete */
- case 0x20023: /* ADP_Stopped_RunTimeErrorUnknown */
- case 0x20024: /* ADP_Stopped_InternalError */
- case 0x20025: /* ADP_Stopped_UserInterruption */
- case 0x20027: /* ADP_Stopped_StackOverflow */
- case 0x20028: /* ADP_Stopped_DivisionByZero */
- case 0x20029: /* ADP_Stopped_OSSpecific */
- default:
- fprintf(stderr, "semihosting: exception %#x\n",
- (unsigned) r1);
+ }
+ return 1;
+}
+
+static int post_result(struct target *target)
+{
+ struct arm *arm = target_to_arm(target);
+
+ /* REVISIT this looks wrong ... ARM11 and Cortex-A8
+ * should work this way at least sometimes.
+ */
+ if (is_arm7_9(target_to_arm7_9(target)) ||
+ is_armv7a(target_to_armv7a(target))) {
+ uint32_t spsr;
+
+ /* return value in R0 */
+ buf_set_u32(arm->core_cache->reg_list[0].value, 0, 32, target->semihosting->result);
+ arm->core_cache->reg_list[0].dirty = 1;
+
+ /* LR --> PC */
+ buf_set_u32(arm->core_cache->reg_list[15].value, 0, 32,
+ buf_get_u32(arm_reg_current(arm, 14)->value, 0, 32));
+ arm->core_cache->reg_list[15].dirty = 1;
+
+ /* saved PSR --> current PSR */
+ spsr = buf_get_u32(arm->spsr->value, 0, 32);
+
+ /* REVISIT should this be arm_set_cpsr(arm, spsr)
+ * instead of a partially unrolled version?
+ */
+
+ buf_set_u32(arm->cpsr->value, 0, 32, spsr);
+ arm->cpsr->dirty = 1;
+ arm->core_mode = spsr & 0x1f;
+ if (spsr & 0x20)
+ arm->core_state = ARM_STATE_THUMB;
+
+ } else if (is_armv8(target_to_armv8(target))) {
+ if (arm->core_state == ARM_STATE_AARCH64) {
+ /* return value in R0 */
+ buf_set_u64(arm->core_cache->reg_list[0].value, 0, 64, target->semihosting->result);
+ arm->core_cache->reg_list[0].dirty = 1;
+
+ uint64_t pc = buf_get_u64(arm->core_cache->reg_list[32].value, 0, 64);
+ buf_set_u64(arm->pc->value, 0, 64, pc + 4);
+ arm->pc->dirty = 1;
}
- return target_call_event_callbacks(target, TARGET_EVENT_HALTED);
-
- case 0x0d: /* SYS_TMPNAM */
- case 0x10: /* SYS_CLOCK */
- case 0x12: /* SYS_SYSTEM */
- case 0x17: /* angel_SWIreason_EnterSVC */
- case 0x30: /* SYS_ELAPSED */
- case 0x31: /* SYS_TICKFREQ */
- default:
- fprintf(stderr, "semihosting: unsupported call %#x\n",
- (unsigned) r0);
- result = -1;
- semihosting_errno = ENOTSUP;
+ } else {
+ /* resume execution, this will be pc+2 to skip over the
+ * bkpt instruction */
+
+ /* return result in R0 */
+ buf_set_u32(arm->core_cache->reg_list[0].value, 0, 32, target->semihosting->result);
+ arm->core_cache->reg_list[0].dirty = 1;
}
- /* resume execution to the original mode */
- buf_set_u32(armv4_5->core_cache->reg_list[0].value, 0, 32, result);
- armv4_5->core_cache->reg_list[0].dirty = 1;
- buf_set_u32(armv4_5->core_cache->reg_list[15].value, 0, 32, lr);
- armv4_5->core_cache->reg_list[15].dirty = 1;
- buf_set_u32(armv4_5->core_cache->reg_list[ARMV4_5_CPSR].value, 0, 32, spsr);
- armv4_5->core_cache->reg_list[ARMV4_5_CPSR].dirty = 1;
- armv4_5->core_mode = spsr & 0x1f;
- if (spsr & 0x20)
- armv4_5->core_state = ARMV4_5_STATE_THUMB;
- return target_resume(target, 1, 0, 0, 0);
+ return ERROR_OK;
+}
+
+/**
+ * Initialize ARM semihosting support.
+ *
+ * @param target Pointer to the ARM target to initialize.
+ * @return An error status if there is a problem during initialization.
+ */
+int arm_semihosting_init(struct target *target)
+{
+ struct arm *arm = target_to_arm(target);
+ assert(arm->setup_semihosting);
+ semihosting_common_init(target, arm->setup_semihosting, post_result);
+
+ return ERROR_OK;
}
/**
* or an error was encountered, in which case the caller must return
* immediately.
*
- * @param target Pointer to the ARM target to process
+ * @param target Pointer to the ARM target to process. This target must
+ * not represent an ARMv6-M or ARMv7-M processor.
* @param retval Pointer to a location where the return code will be stored
* @return non-zero value if a request was processed or an error encountered
*/
int arm_semihosting(struct target *target, int *retval)
{
- struct arm *armv4_5 = target_to_armv4_5(target);
- uint32_t lr, spsr;
+ struct arm *arm = target_to_arm(target);
+ struct armv7a_common *armv7a = target_to_armv7a(target);
+ uint32_t pc, lr, spsr;
+ struct reg *r;
+
+ struct semihosting *semihosting = target->semihosting;
+ if (!semihosting)
+ return 0;
- if (!semihosting_active ||
- armv4_5->core_mode != ARMV4_5_MODE_SVC ||
- buf_get_u32(armv4_5->core_cache->reg_list[15].value, 0, 32) != 0x08)
+ if (!semihosting->is_active)
return 0;
- lr = buf_get_u32(ARMV4_5_CORE_REG_MODE(armv4_5->core_cache, ARMV4_5_MODE_SVC, 14).value, 0, 32);
- spsr = buf_get_u32(armv4_5->spsr->value, 0, 32);
+ if (is_arm7_9(target_to_arm7_9(target)) ||
+ is_armv7a(armv7a)) {
+ uint32_t vbar = 0x00000000;
+
+ if (arm->core_mode != ARM_MODE_SVC)
+ return 0;
+
+ if (is_armv7a(armv7a)) {
+ struct arm_dpm *dpm = armv7a->arm.dpm;
+
+ *retval = dpm->prepare(dpm);
+ if (*retval == ERROR_OK) {
+ *retval = dpm->instr_read_data_r0(dpm,
+ ARMV4_5_MRC(15, 0, 0, 12, 0, 0),
+ &vbar);
+
+ dpm->finish(dpm);
+
+ if (*retval != ERROR_OK)
+ return 1;
+ } else {
+ return 1;
+ }
+ }
+
+ /* Check for PC == 0x00000008 or 0xffff0008: Supervisor Call vector. */
+ r = arm->pc;
+ pc = buf_get_u32(r->value, 0, 32);
+ if (pc != (vbar + 0x00000008) && pc != 0xffff0008)
+ return 0;
+
+ r = arm_reg_current(arm, 14);
+ lr = buf_get_u32(r->value, 0, 32);
+
+ /* Core-specific code should make sure SPSR is retrieved
+ * when the above checks pass...
+ */
+ if (!arm->spsr->valid) {
+ LOG_ERROR("SPSR not valid!");
+ *retval = ERROR_FAIL;
+ return 1;
+ }
+
+ spsr = buf_get_u32(arm->spsr->value, 0, 32);
+
+ /* check instruction that triggered this trap */
+ if (spsr & (1 << 5)) {
+ /* was in Thumb (or ThumbEE) mode */
+ uint8_t insn_buf[2];
+ uint16_t insn;
+
+ *retval = target_read_memory(target, lr-2, 2, 1, insn_buf);
+ if (*retval != ERROR_OK)
+ return 1;
+ insn = target_buffer_get_u16(target, insn_buf);
+
+ /* SVC 0xab */
+ if (insn != 0xDFAB)
+ return 0;
+ } else if (spsr & (1 << 24)) {
+ /* was in Jazelle mode */
+ return 0;
+ } else {
+ /* was in ARM mode */
+ uint8_t insn_buf[4];
+ uint32_t insn;
+
+ *retval = target_read_memory(target, lr-4, 4, 1, insn_buf);
+ if (*retval != ERROR_OK)
+ return 1;
+ insn = target_buffer_get_u32(target, insn_buf);
- /* check instruction that triggered this trap */
- if (spsr & (1 << 5)) {
- /* was in Thumb mode */
- uint8_t insn_buf[2];
+ /* SVC 0x123456 */
+ if (insn != 0xEF123456)
+ return 0;
+ }
+ } else if (is_armv7m(target_to_armv7m(target))) {
uint16_t insn;
- *retval = target_read_memory(target, lr-2, 2, 1, insn_buf);
+
+ if (target->debug_reason != DBG_REASON_BREAKPOINT)
+ return 0;
+
+ r = arm->pc;
+ pc = buf_get_u32(r->value, 0, 32);
+
+ pc &= ~1;
+ *retval = target_read_u16(target, pc, &insn);
if (*retval != ERROR_OK)
return 1;
- insn = target_buffer_get_u16(target, insn_buf);
- if (insn != 0xDFAB)
+
+ /* bkpt 0xAB */
+ if (insn != 0xBEAB)
return 0;
- } else {
- /* was in ARM mode */
- uint8_t insn_buf[4];
- uint32_t insn;
- *retval = target_read_memory(target, lr-4, 4, 1, insn_buf);
- if (*retval != ERROR_OK)
+ } else if (is_armv8(target_to_armv8(target))) {
+ if (target->debug_reason != DBG_REASON_BREAKPOINT)
+ return 0;
+
+ if (arm->core_state == ARM_STATE_AARCH64) {
+ uint32_t insn = 0;
+ r = arm->pc;
+ uint64_t pc64 = buf_get_u64(r->value, 0, 64);
+ *retval = target_read_u32(target, pc64, &insn);
+
+ if (*retval != ERROR_OK)
+ return 1;
+
+ /* bkpt 0xAB */
+ if (insn != 0xD45E0000)
+ return 0;
+ } else
return 1;
- insn = target_buffer_get_u32(target, insn_buf);
- if (insn != 0xEF123456)
+ } else {
+ LOG_ERROR("Unsupported semi-hosting Target");
+ return 0;
+ }
+
+ /* Perform semihosting if we are not waiting on a fileio
+ * operation to complete.
+ */
+ if (!semihosting->hit_fileio) {
+ if (is_armv8(target_to_armv8(target)) &&
+ arm->core_state == ARM_STATE_AARCH64) {
+ /* Read op and param from register x0 and x1 respectively. */
+ semihosting->op = buf_get_u64(arm->core_cache->reg_list[0].value, 0, 64);
+ semihosting->param = buf_get_u64(arm->core_cache->reg_list[1].value, 0, 64);
+ semihosting->word_size_bytes = 8;
+ } else {
+ /* Read op and param from register r0 and r1 respectively. */
+ semihosting->op = buf_get_u32(arm->core_cache->reg_list[0].value, 0, 32);
+ semihosting->param = buf_get_u32(arm->core_cache->reg_list[1].value, 0, 32);
+ semihosting->word_size_bytes = 4;
+ }
+
+ /* Check for ARM operation numbers. */
+ if (0 <= semihosting->op && semihosting->op <= 0x31) {
+ *retval = semihosting_common(target);
+ if (*retval != ERROR_OK) {
+ LOG_ERROR("Failed semihosting operation");
+ return 0;
+ }
+ } else {
+ /* Unknown operation number, not a semihosting call. */
return 0;
+ }
}
- *retval = do_semihosting(target);
- return 1;
+ /* Resume if target it is resumable and we are not waiting on a fileio
+ * operation to complete:
+ */
+ if (semihosting->is_resumable && !semihosting->hit_fileio)
+ return arm_semihosting_resume(target, retval);
+
+ return 0;
}