stlink: better handle target reset/events

[fw/openocd] / src / target / stm32_stlink.c

diff --git a/src/target/stm32_stlink.c b/src/target/stm32_stlink.c
index d00852c201301ebd6ffa1165ec9e290a98c8f642..2493aed2b00c0cfafbdd351848df6e49251eed64 100644 (file)
--- a/src/target/stm32_stlink.c
+++ b/src/target/stm32_stlink.c
@@ -2,6 +2,9 @@
  *   Copyright (C) 2011 by Mathias Kuester                                 *
  *   Mathias Kuester <kesmtp@freenet.de>                                   *
  *                                                                         *
+ *   Copyright (C) 2011 by Spencer Oliver                                  *
+ *   spen@spen-soft.co.uk                                                  *
+ *                                                                         *
  *   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     *
@@ -187,6 +190,16 @@ static int stm32_stlink_store_core_reg_u32(struct target *target,
        return ERROR_OK;
 }
 
+static int stm32_stlink_examine_debug_reason(struct target *target)
+{
+       if ((target->debug_reason != DBG_REASON_DBGRQ)
+                       && (target->debug_reason != DBG_REASON_SINGLESTEP)) {
+               target->debug_reason = DBG_REASON_BREAKPOINT;
+       }
+
+       return ERROR_OK;
+}
+
 static int stm32_stlink_init_arch_info(struct target *target,
                                       struct cortex_m3_common *cortex_m3,
                                       struct jtag_tap *tap)
@@ -201,6 +214,8 @@ static int stm32_stlink_init_arch_info(struct target *target,
        armv7m->load_core_reg_u32 = stm32_stlink_load_core_reg_u32;
        armv7m->store_core_reg_u32 = stm32_stlink_store_core_reg_u32;
 
+       armv7m->examine_debug_reason = stm32_stlink_examine_debug_reason;
+
        return ERROR_OK;
 }
 
@@ -229,8 +244,6 @@ static int stm32_stlink_target_create(struct target *target,
        return ERROR_OK;
 }
 
-static int stm32_stlink_poll(struct target *target);
-
 static int stm32_stlink_examine(struct target *target)
 {
        int retval, i;
@@ -248,8 +261,6 @@ static int stm32_stlink_examine(struct target *target)
        if (!target_was_examined(target)) {
                target_set_examined(target);
 
-               stm32_stlink_poll(target);
-
                LOG_INFO("IDCODE %x", target->tap->idcode);
 
                /* Read from Device Identification Registers */
@@ -296,8 +307,9 @@ static int stm32_stlink_examine(struct target *target)
 static int stm32_stlink_load_context(struct target *target)
 {
        struct armv7m_common *armv7m = target_to_armv7m(target);
+       int num_regs = armv7m->core_cache->num_regs;
 
-       for (unsigned i = 0; i < 23; i++) {
+       for (int i = 0; i < num_regs; i++) {
                if (!armv7m->core_cache->reg_list[i].valid)
                        armv7m->read_core_reg(target, i);
        }
@@ -305,6 +317,57 @@ static int stm32_stlink_load_context(struct target *target)
        return ERROR_OK;
 }
 
+static int stlink_debug_entry(struct target *target)
+{
+       struct armv7m_common *armv7m = target_to_armv7m(target);
+       struct arm *arm = &armv7m->arm;
+       struct reg *r;
+       uint32_t xPSR;
+       int retval;
+
+       retval = armv7m->examine_debug_reason(target);
+       if (retval != ERROR_OK)
+               return retval;
+
+       stm32_stlink_load_context(target);
+
+       r = armv7m->core_cache->reg_list + ARMV7M_xPSR;
+       xPSR = buf_get_u32(r->value, 0, 32);
+
+       /* Are we in an exception handler */
+       if (xPSR & 0x1FF) {
+               armv7m->core_mode = ARMV7M_MODE_HANDLER;
+               armv7m->exception_number = (xPSR & 0x1FF);
+
+               arm->core_mode = ARM_MODE_HANDLER;
+               arm->map = armv7m_msp_reg_map;
+       } else {
+               unsigned control = buf_get_u32(armv7m->core_cache
+                               ->reg_list[ARMV7M_CONTROL].value, 0, 2);
+
+               /* is this thread privileged? */
+               armv7m->core_mode = control & 1;
+               arm->core_mode = armv7m->core_mode
+                               ? ARM_MODE_USER_THREAD
+                               : ARM_MODE_THREAD;
+
+               /* which stack is it using? */
+               if (control & 2)
+                       arm->map = armv7m_psp_reg_map;
+               else
+                       arm->map = armv7m_msp_reg_map;
+
+               armv7m->exception_number = 0;
+       }
+
+       LOG_DEBUG("entered debug state in core mode: %s at PC 0x%" PRIx32 ", target->state: %s",
+               armv7m_mode_strings[armv7m->core_mode],
+               *(uint32_t *)(arm->pc->value),
+               target_state_name(target));
+
+       return retval;
+}
+
 static int stm32_stlink_poll(struct target *target)
 {
        enum target_state state;
@@ -314,8 +377,7 @@ static int stm32_stlink_poll(struct target *target)
        state = stlink_if->layout->api->state(stlink_if->fd);
 
        if (state == TARGET_UNKNOWN) {
-               LOG_ERROR
-                   ("jtag status contains invalid mode value - communication failure");
+               LOG_ERROR("jtag status contains invalid mode value - communication failure");
                return ERROR_TARGET_FAILURE;
        }
 
@@ -323,23 +385,17 @@ static int stm32_stlink_poll(struct target *target)
                return ERROR_OK;
 
        if (state == TARGET_HALTED) {
-               target_call_event_callbacks(target, TARGET_EVENT_DEBUG_HALTED);
                target->state = state;
 
-               stm32_stlink_load_context(target);
+               stlink_debug_entry(target);
 
-               LOG_INFO("halted: PC: 0x%x", buf_get_u32(armv7m->arm.pc->value, 0, 32));
+               target_call_event_callbacks(target, TARGET_EVENT_HALTED);
+               LOG_DEBUG("halted: PC: 0x%x", buf_get_u32(armv7m->arm.pc->value, 0, 32));
        }
 
        return ERROR_OK;
 }
 
-static int stm32_stlink_arch_state(struct target *target)
-{
-       LOG_DEBUG("%s", __func__);
-       return ERROR_OK;
-}
-
 static int stm32_stlink_assert_reset(struct target *target)
 {
        int res;
@@ -361,9 +417,12 @@ static int stm32_stlink_assert_reset(struct target *target)
        /* registers are now invalid */
        register_cache_invalidate(armv7m->core_cache);
 
-       stm32_stlink_load_context(target);
-
-       target->state = TARGET_HALTED;
+       if (target->reset_halt) {
+               target->state = TARGET_RESET;
+               target->debug_reason = DBG_REASON_DBGRQ;
+       } else {
+               target->state = TARGET_HALTED;
+       }
 
        return ERROR_OK;
 }
@@ -486,7 +545,7 @@ static int stm32_stlink_resume(struct target *target, int current,
 
        target->state = TARGET_RUNNING;
 
-       target_call_event_callbacks(target, TARGET_EVENT_DEBUG_RESUMED);
+       target_call_event_callbacks(target, TARGET_EVENT_RESUMED);
 
        return ERROR_OK;
 }
@@ -545,7 +604,7 @@ static int stm32_stlink_step(struct target *target, int current,
        target->debug_reason = DBG_REASON_SINGLESTEP;
        target_call_event_callbacks(target, TARGET_EVENT_HALTED);
 
-       stm32_stlink_load_context(target);
+       stlink_debug_entry(target);
 
        LOG_INFO("halted: PC: 0x%x", buf_get_u32(armv7m->arm.pc->value, 0, 32));
 
@@ -669,7 +728,7 @@ struct target_type stm32_stlink_target = {
        .examine = stm32_stlink_examine,
 
        .poll = stm32_stlink_poll,
-       .arch_state = stm32_stlink_arch_state,
+       .arch_state = armv7m_arch_state,
 
        .assert_reset = stm32_stlink_assert_reset,
        .deassert_reset = stm32_stlink_deassert_reset,