- reverted resume_target to old behaviour
[fw/openocd] / src / target / cortex_m3.c
index 19b0a758bdaad524ac1bc220c934db8853fb5e29..a90baafaf57f96fcdf48bb235448b9faeee4c191 100644 (file)
 int cortex_m3_register_commands(struct command_context_s *cmd_ctx);
 
 /* forward declarations */
-void cortex_m3_unset_all_breakpoints_and_watchpoints(struct target_s *target);
 void cortex_m3_enable_breakpoints(struct target_s *target);
 void cortex_m3_enable_watchpoints(struct target_s *target);
-void cortex_m3_disable_bkpts_and_wpts(struct target_s *target);
 int cortex_m3_target_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc, struct target_s *target);
 int cortex_m3_init_target(struct command_context_s *cmd_ctx, struct target_s *target);
 int cortex_m3_quit();
 int cortex_m3_load_core_reg_u32(target_t *target, enum armv7m_regtype type, u32 num, u32 *value);
 int cortex_m3_store_core_reg_u32(target_t *target, enum armv7m_regtype type, u32 num, u32 value);
 int cortex_m3_target_request_data(target_t *target, u32 size, u8 *buffer);
+int cortex_m3_examine(struct command_context_s *cmd_ctx, struct target_s *target);
+
+#ifdef ARMV7_GDB_HACKS
+extern u8 armv7m_gdb_dummy_cpsr_value[];
+extern reg_t armv7m_gdb_dummy_cpsr_reg;
+#endif
 
 target_type_t cortexm3_target =
 {
@@ -77,6 +81,7 @@ target_type_t cortexm3_target =
        .write_memory = cortex_m3_write_memory,
        .bulk_write_memory = cortex_m3_bulk_write_memory,
        .checksum_memory = armv7m_checksum_memory,
+       .blank_check_memory = armv7m_blank_check_memory,
        
        .run_algorithm = armv7m_run_algorithm,
        
@@ -88,6 +93,7 @@ target_type_t cortexm3_target =
        .register_commands = cortex_m3_register_commands,
        .target_command = cortex_m3_target_command,
        .init_target = cortex_m3_init_target,
+       .examine = cortex_m3_examine,
        .quit = cortex_m3_quit
 };
 
@@ -201,8 +207,6 @@ int cortex_m3_endreset_event(target_t *target)
        }
        swjdp_transaction_endcheck(swjdp);
        
-       /* We are in process context */
-       armv7m_use_context(target, ARMV7M_PROCESS_CONTEXT);
        armv7m_invalidate_core_regs(target);
        return ERROR_OK;
 }
@@ -315,7 +319,15 @@ int cortex_m3_debug_entry(target_t *target)
        }
 
        xPSR = buf_get_u32(armv7m->core_cache->reg_list[ARMV7M_xPSR].value, 0, 32);
-       
+
+#ifdef ARMV7_GDB_HACKS
+       /* copy real xpsr reg for gdb, setting thumb bit */
+       buf_set_u32(armv7m_gdb_dummy_cpsr_value, 0, 32, xPSR);
+       buf_set_u32(armv7m_gdb_dummy_cpsr_value, 5, 1, 1);
+       armv7m_gdb_dummy_cpsr_reg.valid = armv7m->core_cache->reg_list[ARMV7M_xPSR].valid;
+       armv7m_gdb_dummy_cpsr_reg.dirty = armv7m->core_cache->reg_list[ARMV7M_xPSR].dirty;
+#endif
+
        /* For IT instructions xPSR must be reloaded on resume and clear on debug exec */
        if (xPSR & 0xf00)
        {
@@ -323,16 +335,25 @@ int cortex_m3_debug_entry(target_t *target)
                cortex_m3_store_core_reg_u32(target, ARMV7M_REGISTER_CORE_GP, 16, xPSR &~ 0xff);
        }
 
-       /* Now we can load SP core registers */ 
+       /* Now we can load SP core registers */
        for (i = ARMV7M_PRIMASK; i < ARMV7NUMCOREREGS; i++)
        {
                if (!armv7m->core_cache->reg_list[i].valid)
-                       armv7m->read_core_reg(target, i);               
+                       armv7m->read_core_reg(target, i);
        }
 
        /* Are we in an exception handler */
-    armv7m->core_mode = (xPSR & 0x1FF) ? ARMV7M_MODE_HANDLER : ARMV7M_MODE_THREAD;
-    armv7m->exception_number = xPSR & 0x1FF;
+       if (xPSR & 0x1FF)
+       {
+               armv7m->core_mode = ARMV7M_MODE_HANDLER;
+               armv7m->exception_number = (xPSR & 0x1FF);
+       }
+       else
+       {
+               armv7m->core_mode = buf_get_u32(armv7m->core_cache->reg_list[ARMV7M_CONTROL].value, 0, 1);
+               armv7m->exception_number = 0;
+       }
+       
        if (armv7m->exception_number)
        {
                cortex_m3_examine_exception_reason(target);
@@ -412,9 +433,12 @@ int cortex_m3_poll(target_t *target)
                target->state = TARGET_SLEEP;
        */
 
+#if 0
     /* Read Debug Fault Status Register, added to figure out the lockup when running flashtest.script  */
-    ahbap_read_system_atomic_u32(swjdp, NVIC_DFSR, &cortex_m3->nvic_dfsr);
-       LOG_DEBUG("dcb_dhcsr 0x%x, nvic_dfsr 0x%x, target->state: %s", cortex_m3->dcb_dhcsr, cortex_m3->nvic_dfsr, target_state_strings[target->state]);        
+       ahbap_read_system_atomic_u32(swjdp, NVIC_DFSR, &cortex_m3->nvic_dfsr);
+       LOG_DEBUG("dcb_dhcsr 0x%x, nvic_dfsr 0x%x, target->state: %s", cortex_m3->dcb_dhcsr, cortex_m3->nvic_dfsr, target_state_strings[target->state]);
+#endif
+       
        return ERROR_OK;
 }
 
@@ -472,13 +496,6 @@ int cortex_m3_soft_reset_halt(struct target_s *target)
        swjdp_common_t *swjdp = &cortex_m3->swjdp_info;
        u32 dcb_dhcsr = 0;
        int retval, timeout = 0;
-       
-       /* Check that we are using process_context, or change and print warning */
-       if (armv7m_get_context(target) != ARMV7M_PROCESS_CONTEXT)
-       {
-               LOG_DEBUG("Changing to process contex registers");
-               armv7m_use_context(target, ARMV7M_PROCESS_CONTEXT);
-       }
 
        /* Enter debug state on reset, cf. end_reset_event() */
        ahbap_write_system_u32(swjdp, DCB_DEMCR, TRCENA | VC_HARDERR | VC_BUSERR | VC_CORERESET );
@@ -512,28 +529,6 @@ int cortex_m3_soft_reset_halt(struct target_s *target)
        return ERROR_OK;
 }
 
-int cortex_m3_prepare_reset_halt(struct target_s *target)
-{
-       armv7m_common_t *armv7m = target->arch_info;
-       cortex_m3_common_t *cortex_m3 = armv7m->arch_info;
-       swjdp_common_t *swjdp = &cortex_m3->swjdp_info;
-       u32 dcb_demcr, dcb_dhcsr;
-       
-       /* Enable debug requests */
-       ahbap_read_system_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
-       if (!(cortex_m3->dcb_dhcsr & C_DEBUGEN))
-               ahbap_write_system_u32(swjdp, DCB_DHCSR, DBGKEY | C_DEBUGEN );
-       
-       /* Enter debug state on reset, cf. end_reset_event() */
-       ahbap_write_system_atomic_u32(swjdp, DCB_DEMCR, TRCENA | VC_HARDERR | VC_BUSERR | VC_CORERESET );
-       
-       ahbap_read_system_atomic_u32(swjdp, DCB_DHCSR, &dcb_dhcsr);
-       ahbap_read_system_atomic_u32(swjdp, DCB_DEMCR, &dcb_demcr);
-       LOG_DEBUG("dcb_dhcsr 0x%x, dcb_demcr 0x%x, ", dcb_dhcsr, dcb_demcr);
-       
-       return ERROR_OK;
-}
-
 int cortex_m3_resume(struct target_s *target, int current, u32 address, int handle_breakpoints, int debug_execution)
 {
        /* get pointers to arch-specific information */
@@ -551,13 +546,6 @@ int cortex_m3_resume(struct target_s *target, int current, u32 address, int hand
        
        if (!debug_execution)
        {
-               /* Check that we are using process_context, or change and print warning */
-               if (armv7m_get_context(target) != ARMV7M_PROCESS_CONTEXT)
-               {
-                       LOG_DEBUG("Incorrect context in resume");
-                       armv7m_use_context(target, ARMV7M_PROCESS_CONTEXT);
-               }
-               
                target_free_all_working_areas(target);
                cortex_m3_enable_breakpoints(target);
                cortex_m3_enable_watchpoints(target);
@@ -568,12 +556,6 @@ int cortex_m3_resume(struct target_s *target, int current, u32 address, int hand
        dcb_dhcsr = DBGKEY | C_DEBUGEN;
        if (debug_execution)
        {
-               /* Check that we are using debug_context, or change and print warning */
-               if (armv7m_get_context(target) != ARMV7M_DEBUG_CONTEXT)
-               {
-                       LOG_DEBUG("Incorrect context in debug_exec resume");
-                       armv7m_use_context(target, ARMV7M_DEBUG_CONTEXT);
-               }
                /* Disable interrupts */
                /* 
                   We disable interrupts in the PRIMASK register instead of masking with C_MASKINTS,
@@ -604,10 +586,10 @@ int cortex_m3_resume(struct target_s *target, int current, u32 address, int hand
                /* Single step past breakpoint at current address */
                if ((breakpoint = breakpoint_find(target, resume_pc)))
                {
-                               LOG_DEBUG("unset breakpoint at 0x%8.8x", breakpoint->address);
-                               cortex_m3_unset_breakpoint(target, breakpoint);
-                               cortex_m3_single_step_core(target);
-                               cortex_m3_set_breakpoint(target, breakpoint);
+                       LOG_DEBUG("unset breakpoint at 0x%8.8x", breakpoint->address);
+                       cortex_m3_unset_breakpoint(target, breakpoint);
+                       cortex_m3_single_step_core(target);
+                       cortex_m3_set_breakpoint(target, breakpoint);
                }
        }
 
@@ -651,13 +633,6 @@ int cortex_m3_step(struct target_s *target, int current, u32 address, int handle
                LOG_WARNING("target not halted");
                return ERROR_TARGET_NOT_HALTED;
        }
-       
-       /* Check that we are using process_context, or change and print warning */
-       if (armv7m_get_context(target) != ARMV7M_PROCESS_CONTEXT)
-       {
-               LOG_WARNING("Incorrect context in step, must be process");
-               armv7m_use_context(target, ARMV7M_PROCESS_CONTEXT);
-       }
 
        /* current = 1: continue on current pc, otherwise continue at <address> */
        if (!current)
@@ -679,9 +654,8 @@ int cortex_m3_step(struct target_s *target, int current, u32 address, int handle
        ahbap_write_system_atomic_u32(swjdp, DCB_DHCSR, DBGKEY| C_STEP | C_DEBUGEN);
        ahbap_read_system_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
 
-       /* If we run in process context then registers are now invalid */
-       if (armv7m_get_context(target) == ARMV7M_PROCESS_CONTEXT)
-               armv7m_invalidate_core_regs(target);
+       /* registers are now invalid */
+       armv7m_invalidate_core_regs(target);
        
        if (breakpoint)
                cortex_m3_set_breakpoint(target, breakpoint);
@@ -700,7 +674,7 @@ int cortex_m3_assert_reset(target_t *target)
        armv7m_common_t *armv7m = target->arch_info;
        cortex_m3_common_t *cortex_m3 = armv7m->arch_info;
        swjdp_common_t *swjdp = &cortex_m3->swjdp_info;
-       int retval;
+       int assert_srst = 1;
        
        LOG_DEBUG("target->state: %s", target_state_strings[target->state]);
        
@@ -709,10 +683,12 @@ int cortex_m3_assert_reset(target_t *target)
                LOG_ERROR("Can't assert SRST");
                return ERROR_FAIL;
        }
-       /* FIX!!! should this be removed as we're asserting trst anyway? */
-       if ((retval=cortex_m3_prepare_reset_halt(target))!=ERROR_OK)
-               return retval;
        
+       /* Enable debug requests */
+       ahbap_read_system_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
+       if (!(cortex_m3->dcb_dhcsr & C_DEBUGEN))
+               ahbap_write_system_u32(swjdp, DCB_DHCSR, DBGKEY | C_DEBUGEN );
+               
        ahbap_write_system_u32(swjdp, DCB_DCRDR, 0 );
        
        if (target->reset_mode == RESET_RUN)
@@ -724,36 +700,66 @@ int cortex_m3_assert_reset(target_t *target)
                cortex_m3_clear_halt(target);
                                                        
                /* Enter debug state on reset, cf. end_reset_event() */ 
-               ahbap_write_system_u32(swjdp, DCB_DHCSR, DBGKEY | C_DEBUGEN );
                ahbap_write_system_u32(swjdp, DCB_DEMCR, TRCENA | VC_HARDERR | VC_BUSERR);
        }
+       else
+       {
+               /* Enter debug state on reset, cf. end_reset_event() */
+               ahbap_write_system_atomic_u32(swjdp, DCB_DEMCR, TRCENA | VC_HARDERR | VC_BUSERR | VC_CORERESET );
+       }
        
-       if (target->state == TARGET_HALTED || target->state == TARGET_UNKNOWN)
+       /* following hack is to handle luminary reset
+        * when srst is asserted the luminary device seesm to also clear the debug registers
+        * which does not match the armv7 debug TRM */
+               
+       if (strcmp(cortex_m3->variant, "lm3s") == 0)
        {
-       /* assert SRST and TRST */
-       /* system would get ouf sync if we didn't reset test-logic, too */
-       jtag_add_reset(1, 1);
-       jtag_add_sleep(5000);
+               /* get revision of lm3s target, only early silicon has this issue
+                * Fury Rev B, DustDevil Rev B, Tempest all ok */
+               
+               u32 did0;
+               
+               if (target_read_u32(target, 0x400fe000, &did0) == ERROR_OK)
+               {
+                       switch ((did0 >> 16) & 0xff)
+                       {
+                               case 0:
+                                       /* all Sandstorm suffer issue */
+                                       assert_srst = 0;
+                                       break;
+                               
+                               case 1:
+                               case 3:
+                                       /* only Fury/DustDevil rev A suffer reset problems */
+                                       if (((did0 >> 8) & 0xff) == 0)
+                                               assert_srst = 0;
+                                       break;
+                       }
+               }
        }
-
-       if (jtag_reset_config & RESET_SRST_PULLS_TRST)
+       
+       if (assert_srst)
        {
-               jtag_add_reset(1, 1);
-       } else
+               /* default to asserting srst */
+               if (jtag_reset_config & RESET_SRST_PULLS_TRST)
+               {
+                       jtag_add_reset(1, 1);
+               }
+               else
+               {
+                       jtag_add_reset(0, 1);
+               }
+       }
+       else
        {
-               jtag_add_reset(0, 1);
+               /* this causes the luminary device to reset using the watchdog */
+               ahbap_write_system_atomic_u32(swjdp, NVIC_AIRCR, AIRCR_VECTKEY | AIRCR_SYSRESETREQ );
+               LOG_DEBUG("Using Luminary Reset: SYSRESETREQ");
        }
        
        target->state = TARGET_RESET;
        jtag_add_sleep(50000);
        
-       #if 0
-       if ((target->reset_mode==RESET_HALT)||(target->reset_mode==RESET_INIT))
-       {
-               cortex_m3_halt(target);
-       }
-       #endif
-       armv7m_use_context(target, ARMV7M_PROCESS_CONTEXT);
        armv7m_invalidate_core_regs(target);
 
        return ERROR_OK;
@@ -769,11 +775,6 @@ int cortex_m3_deassert_reset(target_t *target)
        return ERROR_OK;
 }
 
-void cortex_m3_unset_all_breakpoints_and_watchpoints(struct target_s *target)
-{
-
-}
-
 void cortex_m3_enable_breakpoints(struct target_s *target)
 {
        breakpoint_t *breakpoint = target->breakpoints;
@@ -803,7 +804,7 @@ int cortex_m3_set_breakpoint(struct target_s *target, breakpoint_t *breakpoint)
                LOG_WARNING("breakpoint already set");
                return ERROR_OK;
        }
-
+    
        if (cortex_m3->auto_bp_type)
        {
                breakpoint->type = (breakpoint->address < 0x20000000) ? BKPT_HARD : BKPT_SOFT;
@@ -885,10 +886,18 @@ int cortex_m3_add_breakpoint(struct target_s *target, breakpoint_t *breakpoint)
        /* get pointers to arch-specific information */
        armv7m_common_t *armv7m = target->arch_info;
        cortex_m3_common_t *cortex_m3 = armv7m->arch_info;
-       
+
        if (cortex_m3->auto_bp_type)
        {
                breakpoint->type = (breakpoint->address < 0x20000000) ? BKPT_HARD : BKPT_SOFT;
+#ifdef ARMV7_GDB_HACKS
+               if (breakpoint->length != 2) {
+                       /* XXX Hack: Replace all breakpoints with length != 2 with
+                        * a hardware breakpoint. */ 
+                       breakpoint->type = BKPT_HARD;
+                       breakpoint->length = 2;
+               }
+#endif
        }
 
        if ((breakpoint->type == BKPT_HARD) && (breakpoint->address >= 0x20000000))
@@ -1118,22 +1127,28 @@ int cortex_m3_load_core_reg_u32(struct target_s *target, enum armv7m_regtype typ
        else if (type == ARMV7M_REGISTER_CORE_SP) /* Special purpose core register */
        {
                /* read other registers */
-               u32 savedram;
-               u32 SYSm;
-               u32 instr;
-               SYSm = num & 0x1F;
+               ahbap_read_coreregister_u32(swjdp, value, 20);
                
-               ahbap_read_system_u32(swjdp, 0x20000000, &savedram);
-               instr = ARMV7M_T_MRS(0, SYSm);
-               ahbap_write_system_u32(swjdp, 0x20000000, ARMV7M_T_MRS(0, SYSm));
-               ahbap_write_coreregister_u32(swjdp, 0x20000000, 15);
-               cortex_m3_single_step_core(target);
-               ahbap_read_coreregister_u32(swjdp, value, 0);
-               armv7m->core_cache->reg_list[0].dirty = armv7m->core_cache->reg_list[0].valid;
-               armv7m->core_cache->reg_list[15].dirty = armv7m->core_cache->reg_list[15].valid;
-               ahbap_write_system_u32(swjdp, 0x20000000, savedram);
-               swjdp_transaction_endcheck(swjdp);
-               LOG_DEBUG("load from special reg %i value 0x%x", SYSm, *value);
+               switch (num)
+               {
+                       case 19:
+                               *value = buf_get_u32((u8*)value, 0, 8);
+                               break;
+                               
+                       case 20:
+                               *value = buf_get_u32((u8*)value, 8, 8);
+                               break;
+                               
+                       case 21:
+                               *value = buf_get_u32((u8*)value, 16, 8);
+                               break;
+                               
+                       case 22:
+                               *value = buf_get_u32((u8*)value, 24, 8);
+                               break;
+               }
+               
+               LOG_DEBUG("load from special reg %i value 0x%x", num, *value);
        }
        else
        {
@@ -1146,12 +1161,24 @@ int cortex_m3_load_core_reg_u32(struct target_s *target, enum armv7m_regtype typ
 int cortex_m3_store_core_reg_u32(struct target_s *target, enum armv7m_regtype type, u32 num, u32 value)
 {
        int retval;
+       u32 reg;
        
        /* get pointers to arch-specific information */
        armv7m_common_t *armv7m = target->arch_info;
        cortex_m3_common_t *cortex_m3 = armv7m->arch_info;
        swjdp_common_t *swjdp = &cortex_m3->swjdp_info;
 
+#ifdef ARMV7_GDB_HACKS
+       /* If the LR register is being modified, make sure it will put us
+        * in "thumb" mode, or an INVSTATE exception will occur. This is a
+        * hack to deal with the fact that gdb will sometimes "forge"
+        * return addresses, and doesn't set the LSB correctly (i.e., when
+        * printing expressions containing function calls, it sets LR=0.) */
+       
+       if (num == 14)
+               value |= 0x01;
+#endif
+        
        if ((type == ARMV7M_REGISTER_CORE_GP) && (num <= ARMV7M_PSP))
        {
                retval = ahbap_write_coreregister_u32(swjdp, value, num);
@@ -1166,23 +1193,31 @@ int cortex_m3_store_core_reg_u32(struct target_s *target, enum armv7m_regtype ty
        else if (type == ARMV7M_REGISTER_CORE_SP) /* Special purpose core register */
        {
                /* write other registers */
-               u32 savedram , tempr0;
-               u32 SYSm;
-               u32 instr;
-               SYSm = num & 0x1F;
                
-               ahbap_read_system_u32(swjdp, 0x20000000, &savedram);
-               instr = ARMV7M_T_MSR(SYSm, 0);
-               ahbap_write_system_u32(swjdp, 0x20000000, ARMV7M_T_MSR(SYSm, 0));
-               ahbap_read_coreregister_u32(swjdp, &tempr0, 0);
-               ahbap_write_coreregister_u32(swjdp, value, 0);
-               ahbap_write_coreregister_u32(swjdp, 0x20000000, 15);
-               cortex_m3_single_step_core(target);
-               ahbap_write_coreregister_u32(swjdp, tempr0, 0);
-               armv7m->core_cache->reg_list[15].dirty = armv7m->core_cache->reg_list[15].valid;
-               ahbap_write_system_u32(swjdp, 0x20000000, savedram);
-               swjdp_transaction_endcheck(swjdp);
-               LOG_DEBUG("write special reg %i value 0x%x ", SYSm, value);
+               ahbap_read_coreregister_u32(swjdp, &reg, 20);
+               
+               switch (num)
+               {
+                       case 19:
+                               buf_set_u32((u8*)&reg, 0, 8, value);
+                               break;
+                               
+                       case 20:
+                               buf_set_u32((u8*)&reg, 8, 8, value);
+                               break;
+                               
+                       case 21:
+                               buf_set_u32((u8*)&reg, 16, 8, value);
+                               break;
+                               
+                       case 22:
+                               buf_set_u32((u8*)&reg, 24, 8, value);
+                               break;
+               }
+               
+               ahbap_write_coreregister_u32(swjdp, reg, 20);
+               
+               LOG_DEBUG("write special reg %i value 0x%x ", num, value);
        }
        else
        {
@@ -1268,6 +1303,13 @@ void cortex_m3_build_reg_cache(target_t *target)
 
 int cortex_m3_init_target(struct command_context_s *cmd_ctx, struct target_s *target)
 {
+       cortex_m3_build_reg_cache(target);
+       return ERROR_OK;
+}
+
+int cortex_m3_examine(struct command_context_s *cmd_ctx, struct target_s *target)
+{
+       int retval;
        u32 cpuid, fpcr, dwtcr, ictr;
        int i;
        
@@ -1275,12 +1317,16 @@ int cortex_m3_init_target(struct command_context_s *cmd_ctx, struct target_s *ta
        armv7m_common_t *armv7m = target->arch_info;
        cortex_m3_common_t *cortex_m3 = armv7m->arch_info;
        swjdp_common_t *swjdp = &cortex_m3->swjdp_info;
+       
+       target->type->examined = 1;
 
-       cortex_m3_build_reg_cache(target);
-       ahbap_debugport_init(swjdp);
+       if ((retval=ahbap_debugport_init(swjdp))!=ERROR_OK)
+               return retval;
 
        /* Read from Device Identification Registers */
-       target_read_u32(target, CPUID, &cpuid);
+       if ((retval=target_read_u32(target, CPUID, &cpuid))!=ERROR_OK)
+               return retval;
+       
        if (((cpuid >> 4) & 0xc3f) == 0xc23)
                LOG_DEBUG("CORTEX-M3 processor detected");
        LOG_DEBUG("cpuid: 0x%8.8x", cpuid);
@@ -1369,6 +1415,8 @@ int cortex_m3_target_request_data(target_t *target, u32 size, u8 *buffer)
 int cortex_m3_handle_target_request(void *priv)
 {
        target_t *target = priv;
+       if (!target->type->examined)
+               return ERROR_OK;
        armv7m_common_t *armv7m = target->arch_info;
        cortex_m3_common_t *cortex_m3 = armv7m->arch_info;
        swjdp_common_t *swjdp = &cortex_m3->swjdp_info;
@@ -1431,6 +1479,15 @@ int cortex_m3_init_arch_info(target_t *target, cortex_m3_common_t *cortex_m3, in
        armv7m->pre_restore_context = NULL;
        armv7m->post_restore_context = NULL;
        
+       if (variant)
+       {
+               cortex_m3->variant = strdup(variant);
+       }
+       else
+       {
+               cortex_m3->variant = strdup("");
+       }
+       
        armv7m_init_arch_info(target, armv7m);  
        armv7m->arch_info = cortex_m3;
        armv7m->load_core_reg_u32 = cortex_m3_load_core_reg_u32;
@@ -1461,7 +1518,6 @@ int cortex_m3_target_command(struct command_context_s *cmd_ctx, char *cmd, char
                variant = args[4];
        
        cortex_m3_init_arch_info(target, cortex_m3, chain_pos, variant);
-       cortex_m3_register_commands(cmd_ctx);
        
        return ERROR_OK;
 }