X-Git-Url: https://review.openocd.org/gitweb?p=openocd.git;a=blobdiff_plain;f=src%2Ftarget%2Fcortex_m.c;h=e8839250456e7979890f5aa0f048d26057ac4c2f;hp=24063a7e6af06dc49bbf083cb0c72a6f05226dcc;hb=a4ac56152d9fc13c3fa479397407d9b86ffb13d8;hpb=4e0371bf718c9eb3a862e3c9b113c95cd4c3a479

diff --git a/src/target/cortex_m.c b/src/target/cortex_m.c
index 24063a7e6a..e883925045 100644
--- a/src/target/cortex_m.c
+++ b/src/target/cortex_m.c
@@ -42,7 +42,7 @@
 
 /* NOTE:  most of this should work fine for the Cortex-M1 and
  * Cortex-M0 cores too, although they're ARMv6-M not ARMv7-M.
- * Some differences:  M0/M1 doesn't have FBP remapping or the
+ * Some differences:  M0/M1 doesn't have FPB remapping or the
  * DWT tracing/profiling support.  (So the cycle counter will
  * not be usable; the other stuff isn't currently used here.)
  *
@@ -51,11 +51,6 @@
  * any longer.
  */
 
-/**
- * Returns the type of a break point required by address location
- */
-#define BKPT_TYPE_BY_ADDR(addr) ((addr) < 0x20000000 ? BKPT_HARD : BKPT_SOFT)
-
 /* forward declarations */
 static int cortex_m_store_core_reg_u32(struct target *target,
 		uint32_t num, uint32_t value);
@@ -141,6 +136,83 @@ static int cortex_m_write_debug_halt_mask(struct target *target,
 	return mem_ap_write_atomic_u32(armv7m->debug_ap, DCB_DHCSR, cortex_m->dcb_dhcsr);
 }
 
+static int cortex_m_set_maskints(struct target *target, bool mask)
+{
+	struct cortex_m_common *cortex_m = target_to_cm(target);
+	if (!!(cortex_m->dcb_dhcsr & C_MASKINTS) != mask)
+		return cortex_m_write_debug_halt_mask(target, mask ? C_MASKINTS : 0, mask ? 0 : C_MASKINTS);
+	else
+		return ERROR_OK;
+}
+
+static int cortex_m_set_maskints_for_halt(struct target *target)
+{
+	struct cortex_m_common *cortex_m = target_to_cm(target);
+	switch (cortex_m->isrmasking_mode) {
+		case CORTEX_M_ISRMASK_AUTO:
+			/* interrupts taken at resume, whether for step or run -> no mask */
+			return cortex_m_set_maskints(target, false);
+
+		case CORTEX_M_ISRMASK_OFF:
+			/* interrupts never masked */
+			return cortex_m_set_maskints(target, false);
+
+		case CORTEX_M_ISRMASK_ON:
+			/* interrupts always masked */
+			return cortex_m_set_maskints(target, true);
+
+		case CORTEX_M_ISRMASK_STEPONLY:
+			/* interrupts masked for single step only -> mask now if MASKINTS
+			 * erratum, otherwise only mask before stepping */
+			return cortex_m_set_maskints(target, cortex_m->maskints_erratum);
+	}
+	return ERROR_OK;
+}
+
+static int cortex_m_set_maskints_for_run(struct target *target)
+{
+	switch (target_to_cm(target)->isrmasking_mode) {
+		case CORTEX_M_ISRMASK_AUTO:
+			/* interrupts taken at resume, whether for step or run -> no mask */
+			return cortex_m_set_maskints(target, false);
+
+		case CORTEX_M_ISRMASK_OFF:
+			/* interrupts never masked */
+			return cortex_m_set_maskints(target, false);
+
+		case CORTEX_M_ISRMASK_ON:
+			/* interrupts always masked */
+			return cortex_m_set_maskints(target, true);
+
+		case CORTEX_M_ISRMASK_STEPONLY:
+			/* interrupts masked for single step only -> no mask */
+			return cortex_m_set_maskints(target, false);
+	}
+	return ERROR_OK;
+}
+
+static int cortex_m_set_maskints_for_step(struct target *target)
+{
+	switch (target_to_cm(target)->isrmasking_mode) {
+		case CORTEX_M_ISRMASK_AUTO:
+			/* the auto-interrupt should already be done -> mask */
+			return cortex_m_set_maskints(target, true);
+
+		case CORTEX_M_ISRMASK_OFF:
+			/* interrupts never masked */
+			return cortex_m_set_maskints(target, false);
+
+		case CORTEX_M_ISRMASK_ON:
+			/* interrupts always masked */
+			return cortex_m_set_maskints(target, true);
+
+		case CORTEX_M_ISRMASK_STEPONLY:
+			/* interrupts masked for single step only -> mask */
+			return cortex_m_set_maskints(target, true);
+	}
+	return ERROR_OK;
+}
+
 static int cortex_m_clear_halt(struct target *target)
 {
 	struct cortex_m_common *cortex_m = target_to_cm(target);
@@ -170,7 +242,7 @@ static int cortex_m_single_step_core(struct target *target)
 	struct armv7m_common *armv7m = &cortex_m->armv7m;
 	int retval;
 
-	/* Mask interrupts before clearing halt, if done already.  This avoids
+	/* Mask interrupts before clearing halt, if not done already.  This avoids
 	 * Erratum 377497 (fixed in r1p0) where setting MASKINTS while clearing
 	 * HALT can put the core into an unknown state.
 	 */
@@ -242,8 +314,8 @@ static int cortex_m_endreset_event(struct target *target)
 			return retval;
 	}
 
-	/* clear any interrupt masking */
-	cortex_m_write_debug_halt_mask(target, 0, C_MASKINTS);
+	/* Restore proper interrupt masking setting for running CPU. */
+	cortex_m_set_maskints_for_run(target);
 
 	/* Enable features controlled by ITM and DWT blocks, and catch only
 	 * the vectors we were told to pay attention to.
@@ -257,7 +329,7 @@ static int cortex_m_endreset_event(struct target *target)
 		return retval;
 
 	/* Paranoia: evidently some (early?) chips don't preserve all the
-	 * debug state (including FBP, DWT, etc) across reset...
+	 * debug state (including FPB, DWT, etc) across reset...
 	 */
 
 	/* Enable FPB */
@@ -267,7 +339,7 @@ static int cortex_m_endreset_event(struct target *target)
 		return retval;
 	}
 
-	cortex_m->fpb_enabled = 1;
+	cortex_m->fpb_enabled = true;
 
 	/* Restore FPB registers */
 	for (i = 0; i < cortex_m->fp_num_code + cortex_m->fp_num_lit; i++) {
@@ -407,6 +479,10 @@ static int cortex_m_debug_entry(struct target *target)
 
 	LOG_DEBUG(" ");
 
+	/* Do this really early to minimize the window where the MASKINTS erratum
+	 * can pile up pending interrupts. */
+	cortex_m_set_maskints_for_halt(target);
+
 	cortex_m_clear_halt(target);
 	retval = mem_ap_read_atomic_u32(armv7m->debug_ap, DCB_DHCSR, &cortex_m->dcb_dhcsr);
 	if (retval != ERROR_OK)
@@ -512,7 +588,10 @@ static int cortex_m_poll(struct target *target)
 	}
 
 	if (cortex_m->dcb_dhcsr & S_RESET_ST) {
-		target->state = TARGET_RESET;
+		if (target->state != TARGET_RESET) {
+			target->state = TARGET_RESET;
+			LOG_INFO("%s: external reset detected", target_name(target));
+		}
 		return ERROR_OK;
 	}
 
@@ -566,6 +645,17 @@ static int cortex_m_poll(struct target *target)
 		}
 	}
 
+	/* Check that target is truly halted, since the target could be resumed externally */
+	if ((prev_target_state == TARGET_HALTED) && !(cortex_m->dcb_dhcsr & S_HALT)) {
+		/* registers are now invalid */
+		register_cache_invalidate(armv7m->arm.core_cache);
+
+		target->state = TARGET_RUNNING;
+		LOG_WARNING("%s: external resume detected", target_name(target));
+		target_call_event_callbacks(target, TARGET_EVENT_RESUMED);
+		retval = ERROR_OK;
+	}
+
 	/* Did we detect a failure condition that we cleared? */
 	if (detected_failure != ERROR_OK)
 		retval = detected_failure;
@@ -602,6 +692,10 @@ static int cortex_m_halt(struct target *target)
 	/* Write to Debug Halting Control and Status Register */
 	cortex_m_write_debug_halt_mask(target, C_HALT, 0);
 
+	/* Do this really early to minimize the window where the MASKINTS erratum
+	 * can pile up pending interrupts. */
+	cortex_m_set_maskints_for_halt(target);
+
 	target->debug_reason = DBG_REASON_DBGRQ;
 
 	return ERROR_OK;
@@ -755,6 +849,7 @@ static int cortex_m_resume(struct target *target, int current,
 	}
 
 	/* Restart core */
+	cortex_m_set_maskints_for_run(target);
 	cortex_m_write_debug_halt_mask(target, 0, C_HALT);
 
 	target->debug_reason = DBG_REASON_NOTHALTED;
@@ -817,10 +912,12 @@ static int cortex_m_step(struct target *target, int current,
 	 * a normal step, otherwise we have to manually step over the bkpt
 	 * instruction - as such simulate a step */
 	if (bkpt_inst_found == false) {
-		/* Automatic ISR masking mode off: Just step over the next instruction */
-		if ((cortex_m->isrmasking_mode != CORTEX_M_ISRMASK_AUTO))
+		if ((cortex_m->isrmasking_mode != CORTEX_M_ISRMASK_AUTO)) {
+			/* Automatic ISR masking mode off: Just step over the next
+			 * instruction, with interrupts on or off as appropriate. */
+			cortex_m_set_maskints_for_step(target);
 			cortex_m_write_debug_halt_mask(target, C_STEP, C_HALT);
-		else {
+		} else {
 			/* Process interrupts during stepping in a way they don't interfere
 			 * debugging.
 			 *
@@ -859,25 +956,38 @@ static int cortex_m_step(struct target *target, int current,
 				LOG_DEBUG("Stepping over next instruction with interrupts disabled");
 				cortex_m_write_debug_halt_mask(target, C_HALT | C_MASKINTS, 0);
 				cortex_m_write_debug_halt_mask(target, C_STEP, C_HALT);
-				/* Re-enable interrupts */
-				cortex_m_write_debug_halt_mask(target, C_HALT, C_MASKINTS);
+				/* Re-enable interrupts if appropriate */
+				cortex_m_write_debug_halt_mask(target, C_HALT, 0);
+				cortex_m_set_maskints_for_halt(target);
 			}
 			else {
 
 				/* Set a temporary break point */
-				if (breakpoint)
+				if (breakpoint) {
 					retval = cortex_m_set_breakpoint(target, breakpoint);
-				else
-					retval = breakpoint_add(target, pc_value, 2, BKPT_TYPE_BY_ADDR(pc_value));
+				} else {
+					enum breakpoint_type type = BKPT_HARD;
+					if (cortex_m->fp_rev == 0 && pc_value > 0x1FFFFFFF) {
+						/* FPB rev.1 cannot handle such addr, try BKPT instr */
+						type = BKPT_SOFT;
+					}
+					retval = breakpoint_add(target, pc_value, 2, type);
+				}
+
 				bool tmp_bp_set = (retval == ERROR_OK);
 
 				/* No more breakpoints left, just do a step */
-				if (!tmp_bp_set)
+				if (!tmp_bp_set) {
+					cortex_m_set_maskints_for_step(target);
 					cortex_m_write_debug_halt_mask(target, C_STEP, C_HALT);
-				else {
+					/* Re-enable interrupts if appropriate */
+					cortex_m_write_debug_halt_mask(target, C_HALT, 0);
+					cortex_m_set_maskints_for_halt(target);
+				} else {
 					/* Start the core */
 					LOG_DEBUG("Starting core to serve pending interrupts");
 					int64_t t_start = timeval_ms();
+					cortex_m_set_maskints_for_run(target);
 					cortex_m_write_debug_halt_mask(target, 0, C_HALT | C_STEP);
 
 					/* Wait for pending handlers to complete or timeout */
@@ -905,12 +1015,14 @@ static int cortex_m_step(struct target *target, int current,
 							"leaving target running");
 					} else {
 						/* Step over next instruction with interrupts disabled */
+						cortex_m_set_maskints_for_step(target);
 						cortex_m_write_debug_halt_mask(target,
 							C_HALT | C_MASKINTS,
 							0);
 						cortex_m_write_debug_halt_mask(target, C_STEP, C_HALT);
-						/* Re-enable interrupts */
-						cortex_m_write_debug_halt_mask(target, C_HALT, C_MASKINTS);
+						/* Re-enable interrupts if appropriate */
+						cortex_m_write_debug_halt_mask(target, C_HALT, 0);
+						cortex_m_set_maskints_for_halt(target);
 					}
 				}
 			}
@@ -1012,8 +1124,7 @@ static int cortex_m_assert_reset(struct target *target)
 
 	if (!target->reset_halt) {
 		/* Set/Clear C_MASKINTS in a separate operation */
-		if (cortex_m->dcb_dhcsr & C_MASKINTS)
-			cortex_m_write_debug_halt_mask(target, 0, C_MASKINTS);
+		cortex_m_set_maskints_for_run(target);
 
 		/* clear any debug flags before resuming */
 		cortex_m_clear_halt(target);
@@ -1043,10 +1154,18 @@ static int cortex_m_assert_reset(struct target *target)
 		retval = ERROR_OK;
 	} else {
 		/* Use a standard Cortex-M3 software reset mechanism.
-		 * We default to using VECRESET as it is supported on all current cores.
+		 * We default to using VECRESET as it is supported on all current cores
+		 * (except Cortex-M0, M0+ and M1 which support SYSRESETREQ only!)
 		 * This has the disadvantage of not resetting the peripherals, so a
 		 * reset-init event handler is needed to perform any peripheral resets.
 		 */
+		if (!cortex_m->vectreset_supported
+				&& reset_config == CORTEX_M_RESET_VECTRESET) {
+			reset_config = CORTEX_M_RESET_SYSRESETREQ;
+			LOG_WARNING("VECTRESET is not supported on this Cortex-M core, using SYSRESETREQ instead.");
+			LOG_WARNING("Set 'cortex_m reset_config sysresetreq'.");
+		}
+
 		LOG_DEBUG("Using Cortex-M %s", (reset_config == CORTEX_M_RESET_SYSRESETREQ)
 			? "SYSRESETREQ" : "VECTRESET");
 
@@ -1131,20 +1250,21 @@ int cortex_m_set_breakpoint(struct target *target, struct breakpoint *breakpoint
 		return ERROR_OK;
 	}
 
-	if (cortex_m->auto_bp_type)
-		breakpoint->type = BKPT_TYPE_BY_ADDR(breakpoint->address);
-
 	if (breakpoint->type == BKPT_HARD) {
 		uint32_t fpcr_value;
 		while (comparator_list[fp_num].used && (fp_num < cortex_m->fp_num_code))
 			fp_num++;
 		if (fp_num >= cortex_m->fp_num_code) {
 			LOG_ERROR("Can not find free FPB Comparator!");
-			return ERROR_FAIL;
+			return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
 		}
 		breakpoint->set = fp_num + 1;
 		fpcr_value = breakpoint->address | 1;
 		if (cortex_m->fp_rev == 0) {
+			if (breakpoint->address > 0x1FFFFFFF) {
+				LOG_ERROR("Cortex-M Flash Patch Breakpoint rev.1 cannot handle HW breakpoint above address 0x1FFFFFFE");
+				return ERROR_FAIL;
+			}
 			uint32_t hilo;
 			hilo = (breakpoint->address & 0x2) ? FPCR_REPLACE_BKPT_HIGH : FPCR_REPLACE_BKPT_LOW;
 			fpcr_value = (fpcr_value & 0x1FFFFFFC) | hilo | 1;
@@ -1152,7 +1272,7 @@ int cortex_m_set_breakpoint(struct target *target, struct breakpoint *breakpoint
 			LOG_ERROR("Unhandled Cortex-M Flash Patch Breakpoint architecture revision");
 			return ERROR_FAIL;
 		}
-		comparator_list[fp_num].used = 1;
+		comparator_list[fp_num].used = true;
 		comparator_list[fp_num].fpcr_value = fpcr_value;
 		target_write_u32(target, comparator_list[fp_num].fpcr_address,
 			comparator_list[fp_num].fpcr_value);
@@ -1167,7 +1287,7 @@ int cortex_m_set_breakpoint(struct target *target, struct breakpoint *breakpoint
 				return retval;
 			}
 
-			cortex_m->fpb_enabled = 1;
+			cortex_m->fpb_enabled = true;
 		}
 	} else if (breakpoint->type == BKPT_SOFT) {
 		uint8_t code[4];
@@ -1226,23 +1346,17 @@ int cortex_m_unset_breakpoint(struct target *target, struct breakpoint *breakpoi
 			LOG_DEBUG("Invalid FP Comparator number in breakpoint");
 			return ERROR_OK;
 		}
-		comparator_list[fp_num].used = 0;
+		comparator_list[fp_num].used = false;
 		comparator_list[fp_num].fpcr_value = 0;
 		target_write_u32(target, comparator_list[fp_num].fpcr_address,
 			comparator_list[fp_num].fpcr_value);
 	} else {
 		/* restore original instruction (kept in target endianness) */
-		if (breakpoint->length == 4) {
-			retval = target_write_memory(target, breakpoint->address & 0xFFFFFFFE, 4, 1,
-					breakpoint->orig_instr);
-			if (retval != ERROR_OK)
-				return retval;
-		} else {
-			retval = target_write_memory(target, breakpoint->address & 0xFFFFFFFE, 2, 1,
+		retval = target_write_memory(target, breakpoint->address & 0xFFFFFFFE,
+					breakpoint->length, 1,
 					breakpoint->orig_instr);
-			if (retval != ERROR_OK)
-				return retval;
-		}
+		if (retval != ERROR_OK)
+			return retval;
 	}
 	breakpoint->set = false;
 
@@ -1251,28 +1365,6 @@ int cortex_m_unset_breakpoint(struct target *target, struct breakpoint *breakpoi
 
 int cortex_m_add_breakpoint(struct target *target, struct breakpoint *breakpoint)
 {
-	struct cortex_m_common *cortex_m = target_to_cm(target);
-
-	if (cortex_m->auto_bp_type)
-		breakpoint->type = BKPT_TYPE_BY_ADDR(breakpoint->address);
-
-	if (breakpoint->type != BKPT_TYPE_BY_ADDR(breakpoint->address)) {
-		if (breakpoint->type == BKPT_HARD) {
-			LOG_INFO("flash patch comparator requested outside code memory region");
-			return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
-		}
-
-		if (breakpoint->type == BKPT_SOFT) {
-			LOG_INFO("soft breakpoint requested in code (flash) memory region");
-			return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
-		}
-	}
-
-	if ((breakpoint->type == BKPT_HARD) && (cortex_m->fp_code_available < 1)) {
-		LOG_INFO("no flash patch comparator unit available for hardware breakpoint");
-		return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
-	}
-
 	if (breakpoint->length == 3) {
 		LOG_DEBUG("Using a two byte breakpoint for 32bit Thumb-2 request");
 		breakpoint->length = 2;
@@ -1283,32 +1375,15 @@ int cortex_m_add_breakpoint(struct target *target, struct breakpoint *breakpoint
 		return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
 	}
 
-	if (breakpoint->type == BKPT_HARD)
-		cortex_m->fp_code_available--;
-
 	return cortex_m_set_breakpoint(target, breakpoint);
 }
 
 int cortex_m_remove_breakpoint(struct target *target, struct breakpoint *breakpoint)
 {
-	struct cortex_m_common *cortex_m = target_to_cm(target);
-
-	/* REVISIT why check? FBP can be updated with core running ... */
-	if (target->state != TARGET_HALTED) {
-		LOG_WARNING("target not halted");
-		return ERROR_TARGET_NOT_HALTED;
-	}
-
-	if (cortex_m->auto_bp_type)
-		breakpoint->type = BKPT_TYPE_BY_ADDR(breakpoint->address);
-
-	if (breakpoint->set)
-		cortex_m_unset_breakpoint(target, breakpoint);
-
-	if (breakpoint->type == BKPT_HARD)
-		cortex_m->fp_code_available++;
+	if (!breakpoint->set)
+		return ERROR_OK;
 
-	return ERROR_OK;
+	return cortex_m_unset_breakpoint(target, breakpoint);
 }
 
 int cortex_m_set_watchpoint(struct target *target, struct watchpoint *watchpoint)
@@ -1341,7 +1416,7 @@ int cortex_m_set_watchpoint(struct target *target, struct watchpoint *watchpoint
 		LOG_ERROR("Can not find free DWT Comparator");
 		return ERROR_FAIL;
 	}
-	comparator->used = 1;
+	comparator->used = true;
 	watchpoint->set = dwt_num + 1;
 
 	comparator->comp = watchpoint->address;
@@ -1398,7 +1473,7 @@ int cortex_m_unset_watchpoint(struct target *target, struct watchpoint *watchpoi
 	}
 
 	comparator = cortex_m->dwt_comparator_list + dwt_num;
-	comparator->used = 0;
+	comparator->used = false;
 	comparator->function = 0;
 	target_write_u32(target, comparator->dwt_comparator_address + 8,
 		comparator->function);
@@ -1787,8 +1862,7 @@ int cortex_m_profiling(struct target *target, uint32_t *samples,
 
 
 		gettimeofday(&now, NULL);
-		if (sample_count >= max_num_samples ||
-			(now.tv_sec >= timeout.tv_sec && now.tv_usec >= timeout.tv_usec)) {
+		if (sample_count >= max_num_samples || timeval_compare(&now, &timeout) > 0) {
 			LOG_INFO("Profiling completed. %" PRIu32 " samples.", sample_count);
 			break;
 		}
@@ -1833,11 +1907,11 @@ static int cortex_m_dwt_set_reg(struct reg *reg, uint8_t *buf)
 
 struct dwt_reg {
 	uint32_t addr;
-	char *name;
+	const char *name;
 	unsigned size;
 };
 
-static struct dwt_reg dwt_base_regs[] = {
+static const struct dwt_reg dwt_base_regs[] = {
 	{ DWT_CTRL, "dwt_ctrl", 32, },
 	/* NOTE that Erratum 532314 (fixed r2p0) affects CYCCNT:  it wrongly
 	 * increments while the core is asleep.
@@ -1846,7 +1920,7 @@ static struct dwt_reg dwt_base_regs[] = {
 	/* plus some 8 bit counters, useful for profiling with TPIU */
 };
 
-static struct dwt_reg dwt_comp[] = {
+static const struct dwt_reg dwt_comp[] = {
 #define DWT_COMPARATOR(i) \
 		{ DWT_COMP0 + 0x10 * (i), "dwt_" #i "_comp", 32, }, \
 		{ DWT_MASK0 + 0x10 * (i), "dwt_" #i "_mask", 4, }, \
@@ -1855,6 +1929,18 @@ static struct dwt_reg dwt_comp[] = {
 	DWT_COMPARATOR(1),
 	DWT_COMPARATOR(2),
 	DWT_COMPARATOR(3),
+	DWT_COMPARATOR(4),
+	DWT_COMPARATOR(5),
+	DWT_COMPARATOR(6),
+	DWT_COMPARATOR(7),
+	DWT_COMPARATOR(8),
+	DWT_COMPARATOR(9),
+	DWT_COMPARATOR(10),
+	DWT_COMPARATOR(11),
+	DWT_COMPARATOR(12),
+	DWT_COMPARATOR(13),
+	DWT_COMPARATOR(14),
+	DWT_COMPARATOR(15),
 #undef DWT_COMPARATOR
 };
 
@@ -1863,7 +1949,7 @@ static const struct reg_arch_type dwt_reg_type = {
 	.set = cortex_m_dwt_set_reg,
 };
 
-static void cortex_m_dwt_addreg(struct target *t, struct reg *r, struct dwt_reg *d)
+static void cortex_m_dwt_addreg(struct target *t, struct reg *r, const struct dwt_reg *d)
 {
 	struct dwt_reg_state *state;
 
@@ -1888,6 +1974,7 @@ void cortex_m_dwt_setup(struct cortex_m_common *cm, struct target *target)
 	int reg, i;
 
 	target_read_u32(target, DWT_CTRL, &dwtcr);
+	LOG_DEBUG("DWT_CTRL: 0x%" PRIx32, dwtcr);
 	if (!dwtcr) {
 		LOG_DEBUG("no DWT");
 		return;
@@ -1993,13 +2080,7 @@ int cortex_m_examine(struct target *target)
 	/* stlink shares the examine handler but does not support
 	 * all its calls */
 	if (!armv7m->stlink) {
-		retval = dap_dp_init(swjdp);
-		if (retval != ERROR_OK) {
-			LOG_ERROR("Could not initialize the debug port");
-			return retval;
-		}
-
-		if (cortex_m->apsel < 0) {
+		if (cortex_m->apsel == DP_APSEL_INVALID) {
 			/* Search for the MEM-AP */
 			retval = dap_find_ap(swjdp, AP_TYPE_AHB_AP, &armv7m->debug_ap);
 			if (retval != ERROR_OK) {
@@ -2031,15 +2112,21 @@ int cortex_m_examine(struct target *target)
 
 		LOG_DEBUG("Cortex-M%d r%" PRId8 "p%" PRId8 " processor detected",
 				i, (uint8_t)((cpuid >> 20) & 0xf), (uint8_t)((cpuid >> 0) & 0xf));
+		cortex_m->maskints_erratum = false;
 		if (i == 7) {
 			uint8_t rev, patch;
 			rev = (cpuid >> 20) & 0xf;
 			patch = (cpuid >> 0) & 0xf;
-			if ((rev == 0) && (patch < 2))
-				LOG_WARNING("Silicon bug: single stepping will enter pending exception handler!");
+			if ((rev == 0) && (patch < 2)) {
+				LOG_WARNING("Silicon bug: single stepping may enter pending exception handler!");
+				cortex_m->maskints_erratum = true;
+			}
 		}
 		LOG_DEBUG("cpuid: 0x%8.8" PRIx32 "", cpuid);
 
+		/* VECTRESET is not supported on Cortex-M0, M0+ and M1 */
+		cortex_m->vectreset_supported = i > 1;
+
 		if (i == 4) {
 			target_read_u32(target, MVFR0, &mvfr0);
 			target_read_u32(target, MVFR1, &mvfr1);
@@ -2096,7 +2183,7 @@ int cortex_m_examine(struct target *target)
 		if (retval != ERROR_OK)
 			return retval;
 
-		if (armv7m->trace_config.config_type != DISABLED) {
+		if (armv7m->trace_config.config_type != TRACE_CONFIG_TYPE_DISABLED) {
 			armv7m_trace_tpiu_config(target);
 			armv7m_trace_itm_config(target);
 		}
@@ -2105,11 +2192,9 @@ int cortex_m_examine(struct target *target)
 
 		/* Setup FPB */
 		target_read_u32(target, FP_CTRL, &fpcr);
-		cortex_m->auto_bp_type = 1;
 		/* bits [14:12] and [7:4] */
 		cortex_m->fp_num_code = ((fpcr >> 8) & 0x70) | ((fpcr >> 4) & 0xF);
 		cortex_m->fp_num_lit = (fpcr >> 8) & 0xF;
-		cortex_m->fp_code_available = cortex_m->fp_num_code;
 		/* Detect flash patch revision, see RM DDI 0403E.b page C1-817.
 		   Revision is zero base, fp_rev == 1 means Rev.2 ! */
 		cortex_m->fp_rev = (fpcr >> 28) & 0xf;
@@ -2229,25 +2314,17 @@ static int cortex_m_handle_target_request(void *priv)
 }
 
 static int cortex_m_init_arch_info(struct target *target,
-	struct cortex_m_common *cortex_m, struct jtag_tap *tap)
+	struct cortex_m_common *cortex_m, struct adiv5_dap *dap)
 {
 	struct armv7m_common *armv7m = &cortex_m->armv7m;
 
 	armv7m_init_arch_info(target, armv7m);
 
-	/*  tap has no dap initialized */
-	if (!tap->dap) {
-		tap->dap = dap_init();
-
-		/* Leave (only) generic DAP stuff for debugport_init() */
-		tap->dap->tap = tap;
-	}
-
 	/* default reset mode is to use srst if fitted
 	 * if not it will use CORTEX_M3_RESET_VECTRESET */
 	cortex_m->soft_reset_config = CORTEX_M_RESET_VECTRESET;
 
-	armv7m->arm.dap = tap->dap;
+	armv7m->arm.dap = dap;
 
 	/* register arch-specific functions */
 	armv7m->examine_debug_reason = cortex_m_examine_debug_reason;
@@ -2259,24 +2336,30 @@ static int cortex_m_init_arch_info(struct target *target,
 	armv7m->load_core_reg_u32 = cortex_m_load_core_reg_u32;
 	armv7m->store_core_reg_u32 = cortex_m_store_core_reg_u32;
 
-	target_register_timer_callback(cortex_m_handle_target_request, 1, 1, target);
+	target_register_timer_callback(cortex_m_handle_target_request, 1,
+		TARGET_TIMER_TYPE_PERIODIC, target);
 
 	return ERROR_OK;
 }
 
 static int cortex_m_target_create(struct target *target, Jim_Interp *interp)
 {
+	struct adiv5_private_config *pc;
+
+	pc = (struct adiv5_private_config *)target->private_config;
+	if (adiv5_verify_config(pc) != ERROR_OK)
+		return ERROR_FAIL;
+
 	struct cortex_m_common *cortex_m = calloc(1, sizeof(struct cortex_m_common));
+	if (cortex_m == NULL) {
+		LOG_ERROR("No memory creating target");
+		return ERROR_FAIL;
+	}
 
 	cortex_m->common_magic = CORTEX_M_COMMON_MAGIC;
-	cortex_m_init_arch_info(target, cortex_m, target->tap);
+	cortex_m->apsel = pc->ap_num;
 
-	if (target->private_config != NULL) {
-		struct adiv5_private_config *pc =
-				(struct adiv5_private_config *)target->private_config;
-		cortex_m->apsel = pc->ap_num;
-	} else
-		cortex_m->apsel = -1;
+	cortex_m_init_arch_info(target, cortex_m, pc->dap);
 
 	return ERROR_OK;
 }
@@ -2299,20 +2382,6 @@ static int cortex_m_verify_pointer(struct command_context *cmd_ctx,
  * cortexm3_target structure, which is only used with CM3 targets.
  */
 
-static const struct {
-	char name[10];
-	unsigned mask;
-} vec_ids[] = {
-	{ "hard_err",   VC_HARDERR, },
-	{ "int_err",    VC_INTERR, },
-	{ "bus_err",    VC_BUSERR, },
-	{ "state_err",  VC_STATERR, },
-	{ "chk_err",    VC_CHKERR, },
-	{ "nocp_err",   VC_NOCPERR, },
-	{ "mm_err",     VC_MMERR, },
-	{ "reset",      VC_CORERESET, },
-};
-
 COMMAND_HANDLER(handle_cortex_m_vector_catch_command)
 {
 	struct target *target = get_current_target(CMD_CTX);
@@ -2321,6 +2390,20 @@ COMMAND_HANDLER(handle_cortex_m_vector_catch_command)
 	uint32_t demcr = 0;
 	int retval;
 
+	static const struct {
+		char name[10];
+		unsigned mask;
+	} vec_ids[] = {
+		{ "hard_err",   VC_HARDERR, },
+		{ "int_err",    VC_INTERR, },
+		{ "bus_err",    VC_BUSERR, },
+		{ "state_err",  VC_STATERR, },
+		{ "chk_err",    VC_CHKERR, },
+		{ "nocp_err",   VC_NOCPERR, },
+		{ "mm_err",     VC_MMERR, },
+		{ "reset",      VC_CORERESET, },
+	};
+
 	retval = cortex_m_verify_pointer(CMD_CTX, cortex_m);
 	if (retval != ERROR_OK)
 		return retval;
@@ -2393,6 +2476,7 @@ COMMAND_HANDLER(handle_cortex_m_mask_interrupts_command)
 		{ .name = "auto", .value = CORTEX_M_ISRMASK_AUTO },
 		{ .name = "off", .value = CORTEX_M_ISRMASK_OFF },
 		{ .name = "on", .value = CORTEX_M_ISRMASK_ON },
+		{ .name = "steponly", .value = CORTEX_M_ISRMASK_STEPONLY },
 		{ .name = NULL, .value = -1 },
 	};
 	const Jim_Nvp *n;
@@ -2412,12 +2496,7 @@ COMMAND_HANDLER(handle_cortex_m_mask_interrupts_command)
 		if (n->name == NULL)
 			return ERROR_COMMAND_SYNTAX_ERROR;
 		cortex_m->isrmasking_mode = n->value;
-
-
-		if (cortex_m->isrmasking_mode == CORTEX_M_ISRMASK_ON)
-			cortex_m_write_debug_halt_mask(target, C_HALT | C_MASKINTS, 0);
-		else
-			cortex_m_write_debug_halt_mask(target, C_HALT, C_MASKINTS);
+		cortex_m_set_maskints_for_halt(target);
 	}
 
 	n = Jim_Nvp_value2name_simple(nvp_maskisr_modes, cortex_m->isrmasking_mode);
@@ -2440,8 +2519,16 @@ COMMAND_HANDLER(handle_cortex_m_reset_config_command)
 	if (CMD_ARGC > 0) {
 		if (strcmp(*CMD_ARGV, "sysresetreq") == 0)
 			cortex_m->soft_reset_config = CORTEX_M_RESET_SYSRESETREQ;
-		else if (strcmp(*CMD_ARGV, "vectreset") == 0)
-			cortex_m->soft_reset_config = CORTEX_M_RESET_VECTRESET;
+
+		else if (strcmp(*CMD_ARGV, "vectreset") == 0) {
+			if (target_was_examined(target)
+					&& !cortex_m->vectreset_supported)
+				LOG_WARNING("VECTRESET is not supported on your Cortex-M core!");
+			else
+				cortex_m->soft_reset_config = CORTEX_M_RESET_VECTRESET;
+
+		} else
+			return ERROR_COMMAND_SYNTAX_ERROR;
 	}
 
 	switch (cortex_m->soft_reset_config) {
@@ -2469,7 +2556,7 @@ static const struct command_registration cortex_m_exec_command_handlers[] = {
 		.handler = handle_cortex_m_mask_interrupts_command,
 		.mode = COMMAND_EXEC,
 		.help = "mask cortex_m interrupts",
-		.usage = "['auto'|'on'|'off']",
+		.usage = "['auto'|'on'|'off'|'steponly']",
 	},
 	{
 		.name = "vector_catch",
@@ -2483,7 +2570,7 @@ static const struct command_registration cortex_m_exec_command_handlers[] = {
 		.handler = handle_cortex_m_reset_config_command,
 		.mode = COMMAND_ANY,
 		.help = "configure software reset handling",
-		.usage = "['srst'|'sysresetreq'|'vectreset']",
+		.usage = "['sysresetreq'|'vectreset']",
 	},
 	COMMAND_REGISTRATION_DONE
 };
@@ -2521,6 +2608,7 @@ struct target_type cortexm_target = {
 	.deassert_reset = cortex_m_deassert_reset,
 	.soft_reset_halt = cortex_m_soft_reset_halt,
 
+	.get_gdb_arch = arm_get_gdb_arch,
 	.get_gdb_reg_list = armv7m_get_gdb_reg_list,
 
 	.read_memory = cortex_m_read_memory,