]> git.sur5r.net Git - openocd/blobdiff - src/target/cortex_m3.c
David Brownell <david-b@pacbell.net>Fix some command helptext:
[openocd] / src / target / cortex_m3.c
index 6079b9ebdeb0f6a920eb9ee2f582512874efd363..ea20dfd14fd47b32a1e2935226b4713ded3ec34b 100644 (file)
@@ -24,7 +24,7 @@
  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  *                                                                         *
  *                                                                         *
- *   Cortex-M3(tm) TRM, ARM DDI 0337C                                      *
+ *   Cortex-M3(tm) TRM, ARM DDI 0337E (r1p1) and 0337G (r2p0)              *
  *                                                                         *
  ***************************************************************************/
 #ifdef HAVE_CONFIG_H
 #include "cortex_m3.h"
 #include "target_request.h"
 #include "target_type.h"
+#include "arm_disassembler.h"
+
+
+#define ARRAY_SIZE(x)  ((int)(sizeof(x)/sizeof((x)[0])))
 
 
 /* cli handling */
@@ -109,11 +113,11 @@ int cortexm3_dap_read_coreregister_u32(swjdp_common_t *swjdp, uint32_t *value, i
 
        /* mem_ap_write_u32(swjdp, DCB_DCRSR, regnum); */
        dap_setup_accessport(swjdp, CSW_32BIT | CSW_ADDRINC_OFF, DCB_DCRSR & 0xFFFFFFF0);
-       dap_ap_write_reg_u32(swjdp, AP_REG_BD0 | (DCB_DCRSR & 0xC), regnum );
+       dap_ap_write_reg_u32(swjdp, AP_REG_BD0 | (DCB_DCRSR & 0xC), regnum);
 
        /* mem_ap_read_u32(swjdp, DCB_DCRDR, value); */
        dap_setup_accessport(swjdp, CSW_32BIT | CSW_ADDRINC_OFF, DCB_DCRDR & 0xFFFFFFF0);
-       dap_ap_read_reg_u32(swjdp, AP_REG_BD0 | (DCB_DCRDR & 0xC), value );
+       dap_ap_read_reg_u32(swjdp, AP_REG_BD0 | (DCB_DCRDR & 0xC), value);
 
        mem_ap_write_u32(swjdp, DCB_DCRDR, dcrdr);
        retval = swjdp_transaction_endcheck(swjdp);
@@ -134,11 +138,11 @@ int cortexm3_dap_write_coreregister_u32(swjdp_common_t *swjdp, uint32_t value, i
 
        /* mem_ap_write_u32(swjdp, DCB_DCRDR, core_regs[i]); */
        dap_setup_accessport(swjdp, CSW_32BIT | CSW_ADDRINC_OFF, DCB_DCRDR & 0xFFFFFFF0);
-       dap_ap_write_reg_u32(swjdp, AP_REG_BD0 | (DCB_DCRDR & 0xC), value );
+       dap_ap_write_reg_u32(swjdp, AP_REG_BD0 | (DCB_DCRDR & 0xC), value);
 
-       /* mem_ap_write_u32(swjdp, DCB_DCRSR, i | DCRSR_WnR     ); */
+       /* mem_ap_write_u32(swjdp, DCB_DCRSR, i | DCRSR_WnR); */
        dap_setup_accessport(swjdp, CSW_32BIT | CSW_ADDRINC_OFF, DCB_DCRSR & 0xFFFFFFF0);
-       dap_ap_write_reg_u32(swjdp, AP_REG_BD0 | (DCB_DCRSR & 0xC), regnum | DCRSR_WnR );
+       dap_ap_write_reg_u32(swjdp, AP_REG_BD0 | (DCB_DCRSR & 0xC), regnum | DCRSR_WnR);
 
        mem_ap_write_u32(swjdp, DCB_DCRDR, dcrdr);
        retval = swjdp_transaction_endcheck(swjdp);
@@ -173,7 +177,7 @@ int cortex_m3_clear_halt(target_t *target)
 
        /* Read Debug Fault Status Register */
        mem_ap_read_atomic_u32(swjdp, NVIC_DFSR, &cortex_m3->nvic_dfsr);
-       /* Write Debug Fault Status Register to enable processing to resume ?? Try with and without this !! */
+       /* Clear Debug Fault Status */
        mem_ap_write_atomic_u32(swjdp, NVIC_DFSR, cortex_m3->nvic_dfsr);
        LOG_DEBUG(" NVIC_DFSR 0x%" PRIx32 "", cortex_m3->nvic_dfsr);
 
@@ -204,7 +208,7 @@ int cortex_m3_single_step_core(target_t *target)
        return ERROR_OK;
 }
 
-int cortex_m3_exec_opcode(target_t *target,uint32_t opcode, int len /* MODE, r0_invalue, &r0_outvalue */ )
+int cortex_m3_exec_opcode(target_t *target,uint32_t opcode, int len /* MODE, r0_invalue, &r0_outvalue */)
 {
        /* get pointers to arch-specific information */
        armv7m_common_t *armv7m = target->arch_info;
@@ -306,8 +310,6 @@ int cortex_m3_examine_debug_reason(target_t *target)
        if ((target->debug_reason != DBG_REASON_DBGRQ)
                && (target->debug_reason != DBG_REASON_SINGLESTEP))
        {
-               /*  INCOMPLETE */
-
                if (cortex_m3->nvic_dfsr & DFSR_BKPT)
                {
                        target->debug_reason = DBG_REASON_BREAKPOINT;
@@ -316,6 +318,10 @@ int cortex_m3_examine_debug_reason(target_t *target)
                }
                else if (cortex_m3->nvic_dfsr & DFSR_DWTTRAP)
                        target->debug_reason = DBG_REASON_WATCHPOINT;
+               else if (cortex_m3->nvic_dfsr & DFSR_VCATCH)
+                       target->debug_reason = DBG_REASON_BREAKPOINT;
+               else /* EXTERNAL, HALTED, DWTTRAP w/o BKPT */
+                       target->debug_reason = DBG_REASON_UNDEFINED;
        }
 
        return ERROR_OK;
@@ -394,7 +400,9 @@ int cortex_m3_debug_entry(target_t *target)
 
        /* Examine target state and mode */
        /* First load register acessible through core debug port*/
-       for (i = 0; i < ARMV7M_PRIMASK; i++)
+       int num_regs = armv7m->core_cache->num_regs;
+
+       for (i = 0; i < num_regs; i++)
        {
                if (!armv7m->core_cache->reg_list[i].valid)
                        armv7m->read_core_reg(target, i);
@@ -417,13 +425,6 @@ 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 */
-       for (i = ARMV7M_PRIMASK; i < ARMV7NUMCOREREGS; i++)
-       {
-               if (!armv7m->core_cache->reg_list[i].valid)
-                       armv7m->read_core_reg(target, i);
-       }
-
        /* Are we in an exception handler */
        if (xPSR & 0x1FF)
        {
@@ -444,7 +445,7 @@ int cortex_m3_debug_entry(target_t *target)
        LOG_DEBUG("entered debug state in core mode: %s at PC 0x%" PRIx32 ", target->state: %s",
                armv7m_mode_strings[armv7m->core_mode],
                *(uint32_t*)(armv7m->core_cache->reg_list[15].value),
-               Jim_Nvp_value2name_simple( nvp_target_state, target->state )->name);
+               target_state_name(target));
 
        if (armv7m->post_debug_entry)
                armv7m->post_debug_entry(target);
@@ -512,16 +513,19 @@ int cortex_m3_poll(target_t *target)
                }
        }
 
-       /*
-       if (cortex_m3->dcb_dhcsr & S_SLEEP)
-               target->state = TARGET_SLEEP;
-       */
+       /* REVISIT when S_SLEEP is set, it's in a Sleep or DeepSleep state.
+        * How best to model low power modes?
+        */
 
-#if 0
-       /* Read Debug Fault Status Register, added to figure out the lockup when running flashtest.script  */
-       mem_ap_read_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, Jim_Nvp_value2name_simple( nvp_target_state, target->state )->name );
-#endif
+       if (target->state == TARGET_UNKNOWN)
+       {
+               /* check if processor is retiring instructions */
+               if (cortex_m3->dcb_dhcsr & S_RETIRE_ST)
+               {
+                       target->state = TARGET_RUNNING;
+                       return ERROR_OK;
+               }
+       }
 
        return ERROR_OK;
 }
@@ -529,7 +533,7 @@ int cortex_m3_poll(target_t *target)
 int cortex_m3_halt(target_t *target)
 {
        LOG_DEBUG("target->state: %s",
-               Jim_Nvp_value2name_simple(nvp_target_state, target->state )->name);
+               target_state_name(target));
 
        if (target->state == TARGET_HALTED)
        {
@@ -664,7 +668,9 @@ int cortex_m3_resume(struct target_s *target, int current, uint32_t address, int
                /* Single step past breakpoint at current address */
                if ((breakpoint = breakpoint_find(target, resume_pc)))
                {
-                       LOG_DEBUG("unset breakpoint at 0x%8.8" PRIx32 "", breakpoint->address);
+                       LOG_DEBUG("unset breakpoint at 0x%8.8" PRIx32 " (ID: %d)", 
+                                         breakpoint->address,
+                                         breakpoint->unique_id );
                        cortex_m3_unset_breakpoint(target, breakpoint);
                        cortex_m3_single_step_core(target);
                        cortex_m3_set_breakpoint(target, breakpoint);
@@ -694,7 +700,7 @@ int cortex_m3_resume(struct target_s *target, int current, uint32_t address, int
        return ERROR_OK;
 }
 
-/* int irqstepcount=0; */
+/* int irqstepcount = 0; */
 int cortex_m3_step(struct target_s *target, int current, uint32_t address, int handle_breakpoints)
 {
        /* get pointers to arch-specific information */
@@ -751,21 +757,24 @@ int cortex_m3_assert_reset(target_t *target)
        int assert_srst = 1;
 
        LOG_DEBUG("target->state: %s",
-               Jim_Nvp_value2name_simple( nvp_target_state, target->state )->name );
+               target_state_name(target));
 
        enum reset_types jtag_reset_config = jtag_get_reset_config();
+
+       /*
+        * We can reset Cortex-M3 targets using just the NVIC without
+        * requiring SRST, getting a SoC reset (or a core-only reset)
+        * instead of a system reset.
+        */
        if (!(jtag_reset_config & RESET_HAS_SRST))
-       {
-               LOG_ERROR("Can't assert SRST");
-               return ERROR_FAIL;
-       }
+               assert_srst = 0;
 
        /* Enable debug requests */
        mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
        if (!(cortex_m3->dcb_dhcsr & C_DEBUGEN))
                mem_ap_write_u32(swjdp, DCB_DHCSR, DBGKEY | C_DEBUGEN);
 
-       mem_ap_write_u32(swjdp, DCB_DCRDR, 0 );
+       mem_ap_write_u32(swjdp, DCB_DCRDR, 0);
 
        if (!target->reset_halt)
        {
@@ -788,15 +797,21 @@ int cortex_m3_assert_reset(target_t *target)
                mem_ap_write_atomic_u32(swjdp, DCB_DEMCR, TRCENA | VC_HARDERR | VC_BUSERR | VC_CORERESET);
        }
 
-       /* 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 */
-
+       /*
+        * When nRST is asserted on most Stellaris devices, it clears some of
+        * the debug state.  The ARMv7M and Cortex-M3 TRMs say that's wrong;
+        * and OpenOCD depends on those TRMs.  So we won't use SRST on those
+        * chips.  (Only power-on reset should affect debug state, beyond a
+        * few specified bits; not the chip's nRST input, wired to SRST.)
+        *
+        * REVISIT current errata specs don't seem to cover this issue.
+        * Do we have more details than this email?
+        *   https://lists.berlios.de/pipermail
+        *      /openocd-development/2008-August/003065.html
+        */
        if (strcmp(target->variant, "lm3s") == 0)
        {
-               /* get revision of lm3s target, only early silicon has this issue
-                * Fury Rev B, DustDevil Rev B, Tempest all ok */
-
+               /* Check for silicon revisions with the issue. */
                uint32_t did0;
 
                if (target_read_u32(target, 0x400fe000, &did0) == ERROR_OK)
@@ -810,10 +825,16 @@ int cortex_m3_assert_reset(target_t *target)
 
                                case 1:
                                case 3:
-                                       /* only Fury/DustDevil rev A suffer reset problems */
+                                       /* Fury and DustDevil rev A have
+                                        * this nRST problem.  It should
+                                        * be fixed in rev B silicon.
+                                        */
                                        if (((did0 >> 8) & 0xff) == 0)
                                                assert_srst = 0;
                                        break;
+                               case 4:
+                                       /* Tempest should be fine. */
+                                       break;
                        }
                }
        }
@@ -832,13 +853,20 @@ int cortex_m3_assert_reset(target_t *target)
        }
        else
        {
-               /* this causes the luminary device to reset using the watchdog */
-               mem_ap_write_atomic_u32(swjdp, NVIC_AIRCR, AIRCR_VECTKEY | AIRCR_SYSRESETREQ);
-               LOG_DEBUG("Using Luminary Reset: SYSRESETREQ");
+               /* Use a standard Cortex-M3 software reset mechanism.
+                * SYSRESETREQ will reset SoC peripherals outside the
+                * core, like watchdog timers, if the SoC wires it up
+                * correctly.  Else VECRESET can reset just the core.
+                */
+               mem_ap_write_atomic_u32(swjdp, NVIC_AIRCR,
+                               AIRCR_VECTKEY | AIRCR_SYSRESETREQ);
+               LOG_DEBUG("Using Cortex-M3 SYSRESETREQ");
 
                {
-                       /* I do not know why this is necessary, but it fixes strange effects
-                        * (step/resume cause a NMI after reset) on LM3S6918 -- Michael Schwingen */
+                       /* I do not know why this is necessary, but it
+                        * fixes strange effects (step/resume cause NMI
+                        * after reset) on LM3S6918 -- Michael Schwingen
+                        */
                        uint32_t tmp;
                        mem_ap_read_atomic_u32(swjdp, NVIC_AIRCR, &tmp);
                }
@@ -862,7 +890,7 @@ int cortex_m3_assert_reset(target_t *target)
 int cortex_m3_deassert_reset(target_t *target)
 {
        LOG_DEBUG("target->state: %s",
-               Jim_Nvp_value2name_simple(nvp_target_state, target->state )->name);
+               target_state_name(target));
 
        /* deassert reset lines */
        jtag_add_reset(0, 0);
@@ -886,7 +914,7 @@ void cortex_m3_enable_breakpoints(struct target_s *target)
 int cortex_m3_set_breakpoint(struct target_s *target, breakpoint_t *breakpoint)
 {
        int retval;
-       int fp_num=0;
+       int fp_num = 0;
        uint32_t hilo;
 
        /* get pointers to arch-specific information */
@@ -897,7 +925,7 @@ int cortex_m3_set_breakpoint(struct target_s *target, breakpoint_t *breakpoint)
 
        if (breakpoint->set)
        {
-               LOG_WARNING("breakpoint already set");
+               LOG_WARNING("breakpoint (BPID: %d) already set", breakpoint->unique_id);
                return ERROR_OK;
        }
 
@@ -943,6 +971,13 @@ int cortex_m3_set_breakpoint(struct target_s *target, breakpoint_t *breakpoint)
                breakpoint->set = 0x11; /* Any nice value but 0 */
        }
 
+       LOG_DEBUG("BPID: %d, Type: %d, Address: 0x%08" PRIx32 " Length: %d (set=%d)", 
+                         breakpoint->unique_id,
+                         (int)(breakpoint->type),
+                         breakpoint->address,
+                         breakpoint->length,
+                         breakpoint->set);
+
        return ERROR_OK;
 }
 
@@ -960,6 +995,13 @@ int cortex_m3_unset_breakpoint(struct target_s *target, breakpoint_t *breakpoint
                return ERROR_OK;
        }
 
+       LOG_DEBUG("BPID: %d, Type: %d, Address: 0x%08" PRIx32 " Length: %d (set=%d)", 
+                         breakpoint->unique_id,
+                         (int)(breakpoint->type),
+                         breakpoint->address,
+                         breakpoint->length,
+                         breakpoint->set);
+
        if (breakpoint->type == BKPT_HARD)
        {
                int fp_num = breakpoint->set - 1;
@@ -1075,7 +1117,7 @@ int cortex_m3_remove_breakpoint(struct target_s *target, breakpoint_t *breakpoin
 
 int cortex_m3_set_watchpoint(struct target_s *target, watchpoint_t *watchpoint)
 {
-       int dwt_num=0;
+       int dwt_num = 0;
        uint32_t mask, temp;
 
        /* get pointers to arch-specific information */
@@ -1085,7 +1127,7 @@ int cortex_m3_set_watchpoint(struct target_s *target, watchpoint_t *watchpoint)
 
        if (watchpoint->set)
        {
-               LOG_WARNING("watchpoint already set");
+               LOG_WARNING("watchpoint (%d) already set", watchpoint->unique_id );
                return ERROR_OK;
        }
 
@@ -1112,16 +1154,19 @@ int cortex_m3_set_watchpoint(struct target_s *target, watchpoint_t *watchpoint)
                comparator_list[dwt_num].mask = mask;
                comparator_list[dwt_num].function = watchpoint->rw + 5;
                target_write_u32(target, comparator_list[dwt_num].dwt_comparator_address, comparator_list[dwt_num].comp);
-               target_write_u32(target, comparator_list[dwt_num].dwt_comparator_address|0x4, comparator_list[dwt_num].mask);
-               target_write_u32(target, comparator_list[dwt_num].dwt_comparator_address|0x8, comparator_list[dwt_num].function);
+               target_write_u32(target, comparator_list[dwt_num].dwt_comparator_address | 0x4, comparator_list[dwt_num].mask);
+               target_write_u32(target, comparator_list[dwt_num].dwt_comparator_address | 0x8, comparator_list[dwt_num].function);
                LOG_DEBUG("dwt_num %i 0x%" PRIx32 " 0x%" PRIx32 " 0x%" PRIx32 "", dwt_num, comparator_list[dwt_num].comp, comparator_list[dwt_num].mask, comparator_list[dwt_num].function);
        }
        else
        {
-               LOG_WARNING("Cannot watch data values");  /* Move this test to add_watchpoint */
+               /* Move this test to add_watchpoint */
+               LOG_WARNING("Cannot watch data values (id: %d)",
+                                 watchpoint->unique_id );
                return ERROR_OK;
        }
-
+       LOG_DEBUG("Watchpoint (ID: %d) address: 0x%08" PRIx32 " set=%d ", 
+                         watchpoint->unique_id, watchpoint->address, watchpoint->set );
        return ERROR_OK;
 
 }
@@ -1136,10 +1181,13 @@ int cortex_m3_unset_watchpoint(struct target_s *target, watchpoint_t *watchpoint
 
        if (!watchpoint->set)
        {
-               LOG_WARNING("watchpoint not set");
+               LOG_WARNING("watchpoint (wpid: %d) not set", watchpoint->unique_id );
                return ERROR_OK;
        }
 
+       LOG_DEBUG("Watchpoint (ID: %d) address: 0x%08" PRIx32 " set=%d ", 
+                         watchpoint->unique_id, watchpoint->address,watchpoint->set );
+
        dwt_num = watchpoint->set - 1;
 
        if ((dwt_num < 0) || (dwt_num >= cortex_m3->dwt_num_comp))
@@ -1149,7 +1197,7 @@ int cortex_m3_unset_watchpoint(struct target_s *target, watchpoint_t *watchpoint
        }
        comparator_list[dwt_num].used = 0;
        comparator_list[dwt_num].function = 0;
-       target_write_u32(target, comparator_list[dwt_num].dwt_comparator_address|0x8, comparator_list[dwt_num].function);
+       target_write_u32(target, comparator_list[dwt_num].dwt_comparator_address | 0x8, comparator_list[dwt_num].function);
 
        watchpoint->set = 0;
 
@@ -1179,6 +1227,7 @@ int cortex_m3_add_watchpoint(struct target_s *target, watchpoint_t *watchpoint)
        }
 
        cortex_m3->dwt_comp_available--;
+       LOG_DEBUG("dwt_comp_available: %d", cortex_m3->dwt_comp_available);
 
        return ERROR_OK;
 }
@@ -1201,6 +1250,7 @@ int cortex_m3_remove_watchpoint(struct target_s *target, watchpoint_t *watchpoin
        }
 
        cortex_m3->dwt_comp_available++;
+       LOG_DEBUG("dwt_comp_available: %d", cortex_m3->dwt_comp_available);
 
        return ERROR_OK;
 }
@@ -1225,8 +1275,12 @@ int cortex_m3_load_core_reg_u32(struct target_s *target, enum armv7m_regtype typ
        armv7m_common_t *armv7m = target->arch_info;
        swjdp_common_t *swjdp = &armv7m->swjdp_info;
 
-       if ((type == ARMV7M_REGISTER_CORE_GP) && (num <= ARMV7M_PSP))
-       {
+       /* NOTE:  we "know" here that the register identifiers used
+        * in the v7m header match the Cortex-M3 Debug Core Register
+        * Selector values for R0..R15, xPSR, MSP, and PSP.
+        */
+       switch (num) {
+       case 0 ... 18:
                /* read a normal core register */
                retval = cortexm3_dap_read_coreregister_u32(swjdp, value, num);
 
@@ -1236,35 +1290,41 @@ int cortex_m3_load_core_reg_u32(struct target_s *target, enum armv7m_regtype typ
                        return ERROR_JTAG_DEVICE_ERROR;
                }
                LOG_DEBUG("load from core reg %i  value 0x%" PRIx32 "",(int)num,*value);
-       }
-       else if (type == ARMV7M_REGISTER_CORE_SP) /* Special purpose core register */
-       {
-               /* read other registers */
+               break;
+
+       case ARMV7M_PRIMASK:
+       case ARMV7M_BASEPRI:
+       case ARMV7M_FAULTMASK:
+       case ARMV7M_CONTROL:
+               /* Cortex-M3 packages these four registers as bitfields
+                * in one Debug Core register.  So say r0 and r2 docs;
+                * it was removed from r1 docs, but still works.
+                */
                cortexm3_dap_read_coreregister_u32(swjdp, value, 20);
 
                switch (num)
                {
-                       case 19:
-                               *value = buf_get_u32((uint8_t*)value, 0, 8);
+                       case ARMV7M_PRIMASK:
+                               *value = buf_get_u32((uint8_t*)value, 0, 1);
                                break;
 
-                       case 20:
+                       case ARMV7M_BASEPRI:
                                *value = buf_get_u32((uint8_t*)value, 8, 8);
                                break;
 
-                       case 21:
-                               *value = buf_get_u32((uint8_t*)value, 16, 8);
+                       case ARMV7M_FAULTMASK:
+                               *value = buf_get_u32((uint8_t*)value, 16, 1);
                                break;
 
-                       case 22:
-                               *value = buf_get_u32((uint8_t*)value, 24, 8);
+                       case ARMV7M_CONTROL:
+                               *value = buf_get_u32((uint8_t*)value, 24, 2);
                                break;
                }
 
                LOG_DEBUG("load from special reg %i value 0x%" PRIx32 "", (int)num, *value);
-       }
-       else
-       {
+               break;
+
+       default:
                return ERROR_INVALID_ARGUMENTS;
        }
 
@@ -1285,14 +1345,19 @@ int cortex_m3_store_core_reg_u32(struct target_s *target, enum armv7m_regtype ty
         * 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)
+        * printing expressions containing function calls, it sets LR = 0.)
+        * Valid exception return codes have bit 0 set too.
+        */
+       if (num == ARMV7M_R14)
                value |= 0x01;
 #endif
 
-       if ((type == ARMV7M_REGISTER_CORE_GP) && (num <= ARMV7M_PSP))
-       {
+       /* NOTE:  we "know" here that the register identifiers used
+        * in the v7m header match the Cortex-M3 Debug Core Register
+        * Selector values for R0..R15, xPSR, MSP, and PSP.
+        */
+       switch (num) {
+       case 0 ... 18:
                retval = cortexm3_dap_write_coreregister_u32(swjdp, value, num);
                if (retval != ERROR_OK)
                {
@@ -1301,38 +1366,43 @@ int cortex_m3_store_core_reg_u32(struct target_s *target, enum armv7m_regtype ty
                        return ERROR_JTAG_DEVICE_ERROR;
                }
                LOG_DEBUG("write core reg %i value 0x%" PRIx32 "", (int)num, value);
-       }
-       else if (type == ARMV7M_REGISTER_CORE_SP) /* Special purpose core register */
-       {
-               /* write other registers */
-
+               break;
+
+       case ARMV7M_PRIMASK:
+       case ARMV7M_BASEPRI:
+       case ARMV7M_FAULTMASK:
+       case ARMV7M_CONTROL:
+               /* Cortex-M3 packages these four registers as bitfields
+                * in one Debug Core register.  So say r0 and r2 docs;
+                * it was removed from r1 docs, but still works.
+                */
                cortexm3_dap_read_coreregister_u32(swjdp, &reg, 20);
 
                switch (num)
                {
-                       case 19:
-                               buf_set_u32((uint8_t*)&reg, 0, 8, value);
+                       case ARMV7M_PRIMASK:
+                               buf_set_u32((uint8_t*)&reg, 0, 1, value);
                                break;
 
-                       case 20:
+                       case ARMV7M_BASEPRI:
                                buf_set_u32((uint8_t*)&reg, 8, 8, value);
                                break;
 
-                       case 21:
-                               buf_set_u32((uint8_t*)&reg, 16, 8, value);
+                       case ARMV7M_FAULTMASK:
+                               buf_set_u32((uint8_t*)&reg, 16, 1, value);
                                break;
 
-                       case 22:
-                               buf_set_u32((uint8_t*)&reg, 24, 8, value);
+                       case ARMV7M_CONTROL:
+                               buf_set_u32((uint8_t*)&reg, 24, 2, value);
                                break;
                }
 
                cortexm3_dap_write_coreregister_u32(swjdp, reg, 20);
 
                LOG_DEBUG("write special reg %i value 0x%" PRIx32 " ", (int)num, value);
-       }
-       else
-       {
+               break;
+
+       default:
                return ERROR_INVALID_ARGUMENTS;
        }
 
@@ -1491,7 +1561,7 @@ int cortex_m3_dcc_read(swjdp_common_t *swjdp, uint8_t *value, uint8_t *ctrl)
 {
        uint16_t dcrdr;
 
-       mem_ap_read_buf_u16( swjdp, (uint8_t*)&dcrdr, 1, DCB_DCRDR);
+       mem_ap_read_buf_u16(swjdp, (uint8_t*)&dcrdr, 1, DCB_DCRDR);
        *ctrl = (uint8_t)dcrdr;
        *value = (uint8_t)(dcrdr >> 8);
 
@@ -1502,7 +1572,7 @@ int cortex_m3_dcc_read(swjdp_common_t *swjdp, uint8_t *value, uint8_t *ctrl)
        if (dcrdr & (1 << 0))
        {
                dcrdr = 0;
-               mem_ap_write_buf_u16( swjdp, (uint8_t*)&dcrdr, 1, DCB_DCRDR);
+               mem_ap_write_buf_u16(swjdp, (uint8_t*)&dcrdr, 1, DCB_DCRDR);
        }
 
        return ERROR_OK;
@@ -1619,6 +1689,114 @@ int cortex_m3_target_create(struct target_s *target, Jim_Interp *interp)
        return ERROR_OK;
 }
 
+/*
+ * REVISIT Thumb2 disassembly should work for all ARMv7 cores, as well
+ * as at least ARM-1156T2.  The interesting thing about Cortex-M is
+ * that *only* Thumb2 disassembly matters.  There are also some small
+ * additions to Thumb2 that are specific to ARMv7-M.
+ */
+static int
+handle_cortex_m3_disassemble_command(struct command_context_s *cmd_ctx,
+               char *cmd, char **args, int argc)
+{
+       int retval = ERROR_OK;
+       target_t *target = get_current_target(cmd_ctx);
+       uint32_t address;
+       unsigned long count;
+       arm_instruction_t cur_instruction;
+
+       if (argc != 2) {
+               command_print(cmd_ctx,
+                       "usage: cortex_m3 disassemble <address> <count>");
+               return ERROR_OK;
+       }
+
+       errno = 0;
+       address = strtoul(args[0], NULL, 0);
+       if (errno)
+               return ERROR_FAIL;
+       count = strtoul(args[1], NULL, 0);
+       if (errno)
+               return ERROR_FAIL;
+
+       while (count--) {
+               retval = thumb2_opcode(target, address, &cur_instruction);
+               if (retval != ERROR_OK)
+                       return retval;
+               command_print(cmd_ctx, "%s", cur_instruction.text);
+               address += cur_instruction.instruction_size;
+       }
+
+       return ERROR_OK;
+}
+
+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, },
+};
+
+static int
+handle_cortex_m3_vector_catch_command(struct command_context_s *cmd_ctx,
+               char *cmd, char **argv, int argc)
+{
+       target_t *target = get_current_target(cmd_ctx);
+       armv7m_common_t *armv7m = target->arch_info;
+       swjdp_common_t *swjdp = &armv7m->swjdp_info;
+       uint32_t demcr = 0;
+       int i;
+
+       mem_ap_read_atomic_u32(swjdp, DCB_DEMCR, &demcr);
+
+       if (argc > 0) {
+               unsigned catch = 0;
+
+               if (argc == 1) {
+                       if (strcmp(argv[0], "all") == 0) {
+                               catch = VC_HARDERR | VC_INTERR | VC_BUSERR
+                                       | VC_STATERR | VC_CHKERR | VC_NOCPERR
+                                       | VC_MMERR | VC_CORERESET;
+                               goto write;
+                       } else if (strcmp(argv[0], "none") == 0) {
+                               goto write;
+                       }
+               }
+               while (argc-- > 0) {
+                       for (i = 0; i < ARRAY_SIZE(vec_ids); i++) {
+                               if (strcmp(argv[argc], vec_ids[i].name) != 0)
+                                       continue;
+                               catch |= vec_ids[i].mask;
+                               break;
+                       }
+                       if (i == ARRAY_SIZE(vec_ids)) {
+                               LOG_ERROR("No CM3 vector '%s'", argv[argc]);
+                               return ERROR_INVALID_ARGUMENTS;
+                       }
+               }
+write:
+               demcr &= ~0xffff;
+               demcr |= catch;
+
+               /* write, but don't assume it stuck */
+               mem_ap_write_u32(swjdp, DCB_DEMCR, demcr);
+               mem_ap_read_atomic_u32(swjdp, DCB_DEMCR, &demcr);
+       }
+
+       for (i = 0; i < ARRAY_SIZE(vec_ids); i++)
+               command_print(cmd_ctx, "%9s: %s", vec_ids[i].name,
+                       (demcr & vec_ids[i].mask) ? "catch" : "ignore");
+
+       return ERROR_OK;
+}
+
 int cortex_m3_register_commands(struct command_context_s *cmd_ctx)
 {
        int retval;
@@ -1626,8 +1804,18 @@ int cortex_m3_register_commands(struct command_context_s *cmd_ctx)
 
        retval = armv7m_register_commands(cmd_ctx);
 
-       cortex_m3_cmd = register_command(cmd_ctx, NULL, "cortex_m3", NULL, COMMAND_ANY, "cortex_m3 specific commands");
-       register_command(cmd_ctx, cortex_m3_cmd, "maskisr", handle_cortex_m3_mask_interrupts_command, COMMAND_EXEC, "mask cortex_m3 interrupts ['on'|'off']");
+       cortex_m3_cmd = register_command(cmd_ctx, NULL, "cortex_m3",
+                       NULL, COMMAND_ANY, "cortex_m3 specific commands");
+
+       register_command(cmd_ctx, cortex_m3_cmd, "disassemble",
+                       handle_cortex_m3_disassemble_command, COMMAND_EXEC,
+                       "disassemble Thumb2 instructions <address> <count>");
+       register_command(cmd_ctx, cortex_m3_cmd, "maskisr",
+                       handle_cortex_m3_mask_interrupts_command, COMMAND_EXEC,
+                       "mask cortex_m3 interrupts ['on'|'off']");
+       register_command(cmd_ctx, cortex_m3_cmd, "vector_catch",
+                       handle_cortex_m3_vector_catch_command, COMMAND_EXEC,
+                       "catch hardware vectors ['all'|'none'|<list>]");
 
        return retval;
 }
@@ -1648,7 +1836,7 @@ int handle_cortex_m3_mask_interrupts_command(struct command_context_s *cmd_ctx,
        {
                if (!strcmp(args[0], "on"))
                {
-                       cortex_m3_write_debug_halt_mask(target, C_HALT|C_MASKINTS, 0);
+                       cortex_m3_write_debug_halt_mask(target, C_HALT | C_MASKINTS, 0);
                }
                else if (!strcmp(args[0], "off"))
                {