]> git.sur5r.net Git - openocd/blobdiff - src/target/mips_m4k.c
Change tap_state naming to be consistent with SVF documentation.
[openocd] / src / target / mips_m4k.c
index e89ee844cd9587bef4fb91691ffc1bccb80a41ed..353126d9e59152b24391a6cf1664113b2a3bc4bf 100644 (file)
@@ -25,6 +25,7 @@
 
 #include "mips32.h"
 #include "mips_m4k.h"
+#include "mips32_dmaacc.h"
 #include "jtag.h"
 #include "log.h"
 
@@ -43,8 +44,8 @@ int mips_m4k_read_memory(struct target_s *target, u32 address, u32 size, u32 cou
 int mips_m4k_write_memory(struct target_s *target, u32 address, u32 size, u32 count, u8 *buffer);
 int mips_m4k_register_commands(struct command_context_s *cmd_ctx);
 int mips_m4k_init_target(struct command_context_s *cmd_ctx, struct target_s *target);
-int mips_m4k_quit();
-int mips_m4k_target_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc, struct target_s *target);
+int mips_m4k_quit(void);
+int mips_m4k_target_create(struct target_s *target, Jim_Interp *interp);
 
 int mips_m4k_examine(struct target_s *target);
 int mips_m4k_assert_reset(target_t *target);
@@ -66,7 +67,7 @@ target_type_t mips_m4k_target =
        .assert_reset = mips_m4k_assert_reset,
        .deassert_reset = mips_m4k_deassert_reset,
        .soft_reset_halt = mips_m4k_soft_reset_halt,
-       
+
        .get_gdb_reg_list = mips32_get_gdb_reg_list,
 
        .read_memory = mips_m4k_read_memory,
@@ -74,7 +75,7 @@ target_type_t mips_m4k_target =
        .bulk_write_memory = mips_m4k_bulk_write_memory,
        .checksum_memory = NULL,
        .blank_check_memory = NULL,
-       
+
        .run_algorithm = mips32_run_algorithm,
 
        .add_breakpoint = mips_m4k_add_breakpoint,
@@ -83,45 +84,74 @@ target_type_t mips_m4k_target =
        .remove_watchpoint = mips_m4k_remove_watchpoint,
 
        .register_commands = mips_m4k_register_commands,
-       .target_command = mips_m4k_target_command,
+       .target_create = mips_m4k_target_create,
        .init_target = mips_m4k_init_target,
        .examine = mips_m4k_examine,
        .quit = mips_m4k_quit
 };
 
+int mips_m4k_examine_debug_reason(target_t *target)
+{
+       int break_status;
+       int retval;
+
+       if ((target->debug_reason != DBG_REASON_DBGRQ)
+               && (target->debug_reason != DBG_REASON_SINGLESTEP))
+       {
+               /* get info about inst breakpoint support */
+               if ((retval = target_read_u32(target, EJTAG_IBS, &break_status)) != ERROR_OK)
+                       return retval;
+               if (break_status & 0x1f)
+               {
+                       /* we have halted on a  breakpoint */
+                       if ((retval = target_write_u32(target, EJTAG_IBS, 0)) != ERROR_OK)
+                               return retval;
+                       target->debug_reason = DBG_REASON_BREAKPOINT;
+               }
+
+               /* get info about data breakpoint support */
+               if ((retval = target_read_u32(target, 0xFF302000, &break_status)) != ERROR_OK)
+                       return retval;
+               if (break_status & 0x1f)
+               {
+                       /* we have halted on a  breakpoint */
+                       if ((retval = target_write_u32(target, 0xFF302000, 0)) != ERROR_OK)
+                               return retval;
+                       target->debug_reason = DBG_REASON_WATCHPOINT;
+               }
+       }
+
+       return ERROR_OK;
+}
+
 int mips_m4k_debug_entry(target_t *target)
 {
-       u32 debug_reg;
        mips32_common_t *mips32 = target->arch_info;
        mips_ejtag_t *ejtag_info = &mips32->ejtag_info;
-       
+       u32 debug_reg;
+
        /* read debug register */
        mips_ejtag_read_debug(ejtag_info, &debug_reg);
-       
-       if ((target->debug_reason != DBG_REASON_DBGRQ)
-               && (target->debug_reason != DBG_REASON_SINGLESTEP))
-       {
-//             if (cortex_m3->nvic_dfsr & DFSR_BKPT)
-//             {
-//                     target->debug_reason = DBG_REASON_BREAKPOINT;
-//                     if (cortex_m3->nvic_dfsr & DFSR_DWTTRAP)
-//                             target->debug_reason = DBG_REASON_WPTANDBKPT;
-//             }
-//             else if (cortex_m3->nvic_dfsr & DFSR_DWTTRAP)
-//                     target->debug_reason = DBG_REASON_WATCHPOINT;
-       }
-       
+
+       /* make sure break uit configured */
+       mips32_configure_break_unit(target);
+
+       /* attempt to find halt reason */
+       mips_m4k_examine_debug_reason(target);
+
+       /* clear single step if active */
        if (debug_reg & EJTAG_DEBUG_DSS)
        {
                /* stopped due to single step - clear step bit */
                mips_ejtag_config_step(ejtag_info, 0);
        }
-       
+
        mips32_save_context(target);
-       
-       LOG_DEBUG("entered debug state at PC 0x%x, target->state: %s", \
-               *(u32*)(mips32->core_cache->reg_list[MIPS32_PC].value), target_state_strings[target->state]);
-       
+
+       LOG_DEBUG("entered debug state at PC 0x%x, target->state: %s",
+               *(u32*)(mips32->core_cache->reg_list[MIPS32_PC].value),
+                 Jim_Nvp_value2name_simple( nvp_target_state, target->state )->name);
+
        return ERROR_OK;
 }
 
@@ -130,33 +160,49 @@ int mips_m4k_poll(target_t *target)
        int retval;
        mips32_common_t *mips32 = target->arch_info;
        mips_ejtag_t *ejtag_info = &mips32->ejtag_info;
-       
+       u32 ejtag_ctrl = ejtag_info->ejtag_ctrl;
+
        /* read ejtag control reg */
-       jtag_add_end_state(TAP_RTI);
+       jtag_add_end_state(TAP_IDLE);
        mips_ejtag_set_instr(ejtag_info, EJTAG_INST_CONTROL, NULL);
-       mips_ejtag_drscan_32(ejtag_info, &ejtag_info->ejtag_ctrl);
-       
-       if (ejtag_info->ejtag_ctrl & EJTAG_CTRL_BRKST)
+       mips_ejtag_drscan_32(ejtag_info, &ejtag_ctrl);
+
+       /* clear this bit before handling polling
+        * as after reset registers will read zero */
+       if (ejtag_ctrl & EJTAG_CTRL_ROCC)
+       {
+               /* we have detected a reset, clear flag
+                * otherwise ejtag will not work */
+               jtag_add_end_state(TAP_IDLE);
+               ejtag_ctrl = ejtag_info->ejtag_ctrl & ~EJTAG_CTRL_ROCC;
+
+               mips_ejtag_set_instr(ejtag_info, EJTAG_INST_CONTROL, NULL);
+               mips_ejtag_drscan_32(ejtag_info, &ejtag_ctrl);
+               LOG_DEBUG("Reset Detected");
+       }
+
+       /* check for processor halted */
+       if (ejtag_ctrl & EJTAG_CTRL_BRKST)
        {
                if ((target->state == TARGET_RUNNING) || (target->state == TARGET_RESET))
                {
-                       jtag_add_end_state(TAP_RTI);
+                       jtag_add_end_state(TAP_IDLE);
                        mips_ejtag_set_instr(ejtag_info, EJTAG_INST_NORMALBOOT, NULL);
-                       
+
                        target->state = TARGET_HALTED;
-                       
+
                        if ((retval = mips_m4k_debug_entry(target)) != ERROR_OK)
                                return retval;
-                       
+
                        target_call_event_callbacks(target, TARGET_EVENT_HALTED);
                }
                else if (target->state == TARGET_DEBUG_RUNNING)
                {
                        target->state = TARGET_HALTED;
-                       
+
                        if ((retval = mips_m4k_debug_entry(target)) != ERROR_OK)
                                return retval;
-                       
+
                        target_call_event_callbacks(target, TARGET_EVENT_DEBUG_HALTED);
                }
        }
@@ -164,21 +210,9 @@ int mips_m4k_poll(target_t *target)
        {
                target->state = TARGET_RUNNING;
        }
-       
-       if (ejtag_info->ejtag_ctrl & EJTAG_CTRL_ROCC)
-       {
-               /* we have detected a reset, clear flag
-                * otherwise ejtag will not work */
-               jtag_add_end_state(TAP_RTI);
-               ejtag_info->ejtag_ctrl &= ~EJTAG_CTRL_ROCC;
-               
-               mips_ejtag_set_instr(ejtag_info, EJTAG_INST_CONTROL, NULL);
-               mips_ejtag_drscan_32(ejtag_info, &ejtag_info->ejtag_ctrl);
-               LOG_DEBUG("Reset Detected");
-       }
-       
-//     LOG_DEBUG("ctrl=0x%08X", ejtag_info->ejtag_ctrl);
-       
+
+//     LOG_DEBUG("ctrl=0x%08X", ejtag_ctrl);
+
        return ERROR_OK;
 }
 
@@ -186,21 +220,22 @@ int mips_m4k_halt(struct target_s *target)
 {
        mips32_common_t *mips32 = target->arch_info;
        mips_ejtag_t *ejtag_info = &mips32->ejtag_info;
-       
-       LOG_DEBUG("target->state: %s", target_state_strings[target->state]);
-       
+
+       LOG_DEBUG("target->state: %s",
+                 Jim_Nvp_value2name_simple( nvp_target_state, target->state )->name);
+
        if (target->state == TARGET_HALTED)
        {
                LOG_DEBUG("target was already halted");
                return ERROR_OK;
        }
-       
+
        if (target->state == TARGET_UNKNOWN)
        {
                LOG_WARNING("target was in unknown state when halt was requested");
        }
-       
-       if (target->state == TARGET_RESET) 
+
+       if (target->state == TARGET_RESET)
        {
                if ((jtag_reset_config & RESET_SRST_PULLS_TRST) && jtag_srst)
                {
@@ -213,16 +248,16 @@ int mips_m4k_halt(struct target_s *target)
                         * debug entry was already prepared in mips32_prepare_reset_halt()
                         */
                        target->debug_reason = DBG_REASON_DBGRQ;
-                       
+
                        return ERROR_OK;
                }
        }
-       
+
        /* break processor */
        mips_ejtag_enter_debug(ejtag_info);
-       
+
        target->debug_reason = DBG_REASON_DBGRQ;
-       
+
        return ERROR_OK;
 }
 
@@ -230,52 +265,72 @@ int mips_m4k_assert_reset(target_t *target)
 {
        mips32_common_t *mips32 = target->arch_info;
        mips_ejtag_t *ejtag_info = &mips32->ejtag_info;
-       
-       LOG_DEBUG("target->state: %s", target_state_strings[target->state]);
-       
+       mips_m4k_common_t *mips_m4k = mips32->arch_info;
+
+       LOG_DEBUG("target->state: %s",
+               Jim_Nvp_value2name_simple( nvp_target_state, target->state )->name);
+
        if (!(jtag_reset_config & RESET_HAS_SRST))
        {
                LOG_ERROR("Can't assert SRST");
                return ERROR_FAIL;
        }
-       
+
        if (target->reset_halt)
        {
                /* use hardware to catch reset */
-               jtag_add_end_state(TAP_RTI);
+               jtag_add_end_state(TAP_IDLE);
                mips_ejtag_set_instr(ejtag_info, EJTAG_INST_EJTAGBOOT, NULL);
        }
        else
        {
-               jtag_add_end_state(TAP_RTI);
+               jtag_add_end_state(TAP_IDLE);
                mips_ejtag_set_instr(ejtag_info, EJTAG_INST_NORMALBOOT, NULL);
        }
-       
-       /* here we should issue a srst only, but we may have to assert trst as well */
-       if (jtag_reset_config & RESET_SRST_PULLS_TRST)
+
+       if (strcmp(mips_m4k->variant, "ejtag_srst") == 0)
        {
-               jtag_add_reset(1, 1);
+               u32 ejtag_ctrl = ejtag_info->ejtag_ctrl | EJTAG_CTRL_PRRST | EJTAG_CTRL_PERRST;
+               LOG_DEBUG("Using EJTAG reset (PRRST) to reset processor...");
+               mips_ejtag_set_instr(ejtag_info, EJTAG_INST_CONTROL, NULL);
+               mips_ejtag_drscan_32(ejtag_info, &ejtag_ctrl);
        }
        else
        {
-               jtag_add_reset(0, 1);
+               /* here we should issue a srst only, but we may have to assert trst as well */
+               if (jtag_reset_config & RESET_SRST_PULLS_TRST)
+               {
+                       jtag_add_reset(1, 1);
+               }
+               else
+               {
+                       jtag_add_reset(0, 1);
+               }
        }
-       
+
        target->state = TARGET_RESET;
        jtag_add_sleep(50000);
 
        mips32_invalidate_core_regs(target);
 
+       if (target->reset_halt)
+       {
+               int retval;
+               if ((retval = target_halt(target))!=ERROR_OK)
+                       return retval;
+       }
+
        return ERROR_OK;
 }
 
 int mips_m4k_deassert_reset(target_t *target)
 {
-       LOG_DEBUG("target->state: %s", target_state_strings[target->state]);
-       
+       LOG_DEBUG("target->state: %s",
+               Jim_Nvp_value2name_simple( nvp_target_state, target->state )->name);
+
        /* deassert reset lines */
        jtag_add_reset(0, 0);
-       
+
        return ERROR_OK;
 }
 
@@ -285,38 +340,54 @@ int mips_m4k_soft_reset_halt(struct target_s *target)
        return ERROR_OK;
 }
 
+int mips_m4k_single_step_core(target_t *target)
+{
+       mips32_common_t *mips32 = target->arch_info;
+       mips_ejtag_t *ejtag_info = &mips32->ejtag_info;
+
+       /* configure single step mode */
+       mips_ejtag_config_step(ejtag_info, 1);
+
+       /* exit debug mode */
+       mips_ejtag_exit_debug(ejtag_info, 1);
+
+       mips_m4k_debug_entry(target);
+
+       return ERROR_OK;
+}
+
 int mips_m4k_resume(struct target_s *target, int current, u32 address, int handle_breakpoints, int debug_execution)
 {
        mips32_common_t *mips32 = target->arch_info;
        mips_ejtag_t *ejtag_info = &mips32->ejtag_info;
        breakpoint_t *breakpoint = NULL;
        u32 resume_pc;
-       
+
        if (target->state != TARGET_HALTED)
        {
                LOG_WARNING("target not halted");
                return ERROR_TARGET_NOT_HALTED;
        }
-       
+
        if (!debug_execution)
        {
                target_free_all_working_areas(target);
                mips_m4k_enable_breakpoints(target);
                mips_m4k_enable_watchpoints(target);
        }
-       
+
        /* current = 1: continue on current pc, otherwise continue at <address> */
-       if (!current) 
+       if (!current)
        {
                buf_set_u32(mips32->core_cache->reg_list[MIPS32_PC].value, 0, 32, address);
                mips32->core_cache->reg_list[MIPS32_PC].dirty = 1;
                mips32->core_cache->reg_list[MIPS32_PC].valid = 1;
        }
-       
+
        resume_pc = buf_get_u32(mips32->core_cache->reg_list[MIPS32_PC].value, 0, 32);
-       
+
        mips32_restore_context(target);
-       
+
        /* the front-end may request us not to handle breakpoints */
        if (handle_breakpoints)
        {
@@ -325,17 +396,18 @@ int mips_m4k_resume(struct target_s *target, int current, u32 address, int handl
                {
                        LOG_DEBUG("unset breakpoint at 0x%8.8x", breakpoint->address);
                        mips_m4k_unset_breakpoint(target, breakpoint);
-                       //mips_m4k_single_step_core(target);
+                       mips_m4k_single_step_core(target);
                        mips_m4k_set_breakpoint(target, breakpoint);
                }
        }
-       
+
        /* exit debug mode - enable interrupts if required */
        mips_ejtag_exit_debug(ejtag_info, !debug_execution);
-       
+       target->debug_reason = DBG_REASON_NOTHALTED;
+
        /* registers are now invalid */
        mips32_invalidate_core_regs(target);
-       
+
        if (!debug_execution)
        {
                target->state = TARGET_RUNNING;
@@ -348,7 +420,7 @@ int mips_m4k_resume(struct target_s *target, int current, u32 address, int handl
                target_call_event_callbacks(target, TARGET_EVENT_DEBUG_RESUMED);
                LOG_DEBUG("target debug resumed at 0x%x", resume_pc);
        }
-       
+
        return ERROR_OK;
 }
 
@@ -368,43 +440,43 @@ int mips_m4k_step(struct target_s *target, int current, u32 address, int handle_
        /* current = 1: continue on current pc, otherwise continue at <address> */
        if (!current)
                buf_set_u32(mips32->core_cache->reg_list[MIPS32_PC].value, 0, 32, address);
-       
+
        /* the front-end may request us not to handle breakpoints */
        if (handle_breakpoints)
                if ((breakpoint = breakpoint_find(target, buf_get_u32(mips32->core_cache->reg_list[MIPS32_PC].value, 0, 32))))
                        mips_m4k_unset_breakpoint(target, breakpoint);
-       
+
        /* restore context */
        mips32_restore_context(target);
-       
+
        /* configure single step mode */
        mips_ejtag_config_step(ejtag_info, 1);
-       
+
        target->debug_reason = DBG_REASON_SINGLESTEP;
-       
+
        target_call_event_callbacks(target, TARGET_EVENT_RESUMED);
-       
+
        /* exit debug mode */
        mips_ejtag_exit_debug(ejtag_info, 1);
-       
+
        /* registers are now invalid */
        mips32_invalidate_core_regs(target);
-       
+
        if (breakpoint)
                mips_m4k_set_breakpoint(target, breakpoint);
 
        LOG_DEBUG("target stepped ");
-       
+
        mips_m4k_debug_entry(target);
        target_call_event_callbacks(target, TARGET_EVENT_HALTED);
-       
+
        return ERROR_OK;
 }
 
 void mips_m4k_enable_breakpoints(struct target_s *target)
 {
        breakpoint_t *breakpoint = target->breakpoints;
-       
+
        /* set any pending breakpoints */
        while (breakpoint)
        {
@@ -416,25 +488,114 @@ void mips_m4k_enable_breakpoints(struct target_s *target)
 
 int mips_m4k_set_breakpoint(struct target_s *target, breakpoint_t *breakpoint)
 {
-       /* TODO */
+       mips32_common_t *mips32 = target->arch_info;
+       mips32_comparator_t * comparator_list = mips32->inst_break_list;
+
+       if (breakpoint->set)
+       {
+               LOG_WARNING("breakpoint already set");
+               return ERROR_OK;
+       }
+
+       if (breakpoint->type == BKPT_HARD)
+       {
+               int bp_num = 0;
+
+               while(comparator_list[bp_num].used && (bp_num < mips32->num_inst_bpoints))
+                       bp_num++;
+               if (bp_num >= mips32->num_inst_bpoints)
+               {
+                       LOG_DEBUG("ERROR Can not find free FP Comparator");
+                       LOG_WARNING("ERROR Can not find free FP Comparator");
+                       exit(-1);
+               }
+               breakpoint->set = bp_num + 1;
+               comparator_list[bp_num].used = 1;
+               comparator_list[bp_num].bp_value = breakpoint->address;
+               target_write_u32(target, comparator_list[bp_num].reg_address, comparator_list[bp_num].bp_value);
+               target_write_u32(target, comparator_list[bp_num].reg_address + 0x08, 0x00000000);
+               target_write_u32(target, comparator_list[bp_num].reg_address + 0x18, 1);
+               LOG_DEBUG("bp_num %i bp_value 0x%x", bp_num, comparator_list[bp_num].bp_value);
+       }
+       else if (breakpoint->type == BKPT_SOFT)
+       {
+
+       }
+
        return ERROR_OK;
 }
 
 int mips_m4k_unset_breakpoint(struct target_s *target, breakpoint_t *breakpoint)
 {
-       /* TODO */
+       /* get pointers to arch-specific information */
+       mips32_common_t *mips32 = target->arch_info;
+       mips32_comparator_t * comparator_list = mips32->inst_break_list;
+
+       if (!breakpoint->set)
+       {
+               LOG_WARNING("breakpoint not set");
+               return ERROR_OK;
+       }
+
+       if (breakpoint->type == BKPT_HARD)
+       {
+               int bp_num = breakpoint->set - 1;
+               if ((bp_num < 0) || (bp_num >= mips32->num_inst_bpoints))
+               {
+                       LOG_DEBUG("Invalid FP Comparator number in breakpoint");
+                       return ERROR_OK;
+               }
+               comparator_list[bp_num].used = 0;
+               comparator_list[bp_num].bp_value = 0;
+               target_write_u32(target, comparator_list[bp_num].reg_address + 0x18, 0);
+       }
+       else
+       {
+
+       }
+       breakpoint->set = 0;
+
        return ERROR_OK;
 }
 
 int mips_m4k_add_breakpoint(struct target_s *target, breakpoint_t *breakpoint)
 {
-       /* TODO */
+       mips32_common_t *mips32 = target->arch_info;
+
+       if (mips32->num_inst_bpoints_avail < 1)
+       {
+               LOG_INFO("no hardware breakpoint available");
+               return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
+       }
+
+       /* default to hardware for now */
+       breakpoint->type = BKPT_HARD;
+
+       mips32->num_inst_bpoints_avail--;
+       mips_m4k_set_breakpoint(target, breakpoint);
+
        return ERROR_OK;
 }
 
 int mips_m4k_remove_breakpoint(struct target_s *target, breakpoint_t *breakpoint)
 {
-       /* TODO */
+       /* get pointers to arch-specific information */
+       mips32_common_t *mips32 = target->arch_info;
+
+       if (target->state != TARGET_HALTED)
+       {
+               LOG_WARNING("target not halted");
+               return ERROR_TARGET_NOT_HALTED;
+       }
+
+       if (breakpoint->set)
+       {
+               mips_m4k_unset_breakpoint(target, breakpoint);
+       }
+
+       if (breakpoint->type == BKPT_HARD)
+               mips32->num_inst_bpoints_avail++;
+
        return ERROR_OK;
 }
 
@@ -465,7 +626,7 @@ int mips_m4k_remove_watchpoint(struct target_s *target, watchpoint_t *watchpoint
 void mips_m4k_enable_watchpoints(struct target_s *target)
 {
        watchpoint_t *watchpoint = target->watchpoints;
-       
+
        /* set any pending watchpoints */
        while (watchpoint)
        {
@@ -479,7 +640,7 @@ int mips_m4k_read_memory(struct target_s *target, u32 address, u32 size, u32 cou
 {
        mips32_common_t *mips32 = target->arch_info;
        mips_ejtag_t *ejtag_info = &mips32->ejtag_info;
-       
+
        LOG_DEBUG("address: 0x%8.8x, size: 0x%8.8x, count: 0x%8.8x", address, size, count);
 
        if (target->state != TARGET_HALTED)
@@ -494,13 +655,17 @@ int mips_m4k_read_memory(struct target_s *target, u32 address, u32 size, u32 cou
 
        if (((size == 4) && (address & 0x3u)) || ((size == 2) && (address & 0x1u)))
                return ERROR_TARGET_UNALIGNED_ACCESS;
-       
+
        switch (size)
        {
                case 4:
                case 2:
                case 1:
-                       return mips32_pracc_read_mem(ejtag_info, address, size, count, (void *)buffer);
+                       /* if noDMA off, use DMAACC mode for memory read */
+                       if(ejtag_info->impcode & EJTAG_IMP_NODMA)
+                               return mips32_pracc_read_mem(ejtag_info, address, size, count, (void *)buffer);
+                       else
+                               return mips32_dmaacc_read_mem(ejtag_info, address, size, count, (void *)buffer);
                default:
                        LOG_ERROR("BUG: we shouldn't get here");
                        exit(-1);
@@ -514,7 +679,7 @@ int mips_m4k_write_memory(struct target_s *target, u32 address, u32 size, u32 co
 {
        mips32_common_t *mips32 = target->arch_info;
        mips_ejtag_t *ejtag_info = &mips32->ejtag_info;
-       
+
        LOG_DEBUG("address: 0x%8.8x, size: 0x%8.8x, count: 0x%8.8x", address, size, count);
 
        if (target->state != TARGET_HALTED)
@@ -529,27 +694,31 @@ int mips_m4k_write_memory(struct target_s *target, u32 address, u32 size, u32 co
 
        if (((size == 4) && (address & 0x3u)) || ((size == 2) && (address & 0x1u)))
                return ERROR_TARGET_UNALIGNED_ACCESS;
-       
+
        switch (size)
        {
                case 4:
                case 2:
                case 1:
-                       mips32_pracc_write_mem(ejtag_info, address, size, count, (void *)buffer);
+                       /* if noDMA off, use DMAACC mode for memory write */
+                       if(ejtag_info->impcode & EJTAG_IMP_NODMA)
+                               mips32_pracc_write_mem(ejtag_info, address, size, count, (void *)buffer);
+                       else
+                               mips32_dmaacc_write_mem(ejtag_info, address, size, count, (void *)buffer);
                        break;
                default:
                        LOG_ERROR("BUG: we shouldn't get here");
                        exit(-1);
                        break;
        }
-       
+
        return ERROR_OK;
 }
 
 int mips_m4k_register_commands(struct command_context_s *cmd_ctx)
 {
        int retval;
-       
+
        retval = mips32_register_commands(cmd_ctx);
        return retval;
 }
@@ -557,19 +726,19 @@ int mips_m4k_register_commands(struct command_context_s *cmd_ctx)
 int mips_m4k_init_target(struct command_context_s *cmd_ctx, struct target_s *target)
 {
        mips32_build_reg_cache(target);
-       
+
        return ERROR_OK;
 }
 
-int mips_m4k_quit()
+int mips_m4k_quit(void)
 {
        return ERROR_OK;
 }
 
-int mips_m4k_init_arch_info(target_t *target, mips_m4k_common_t *mips_m4k, int chain_pos, char *variant)
+int mips_m4k_init_arch_info(target_t *target, mips_m4k_common_t *mips_m4k, jtag_tap_t *tap, const char *variant)
 {
        mips32_common_t *mips32 = &mips_m4k->mips32_common;
-       
+
        if (variant)
        {
                mips_m4k->variant = strdup(variant);
@@ -578,35 +747,22 @@ int mips_m4k_init_arch_info(target_t *target, mips_m4k_common_t *mips_m4k, int c
        {
                mips_m4k->variant = strdup("");
        }
-       
+
        mips_m4k->common_magic = MIPSM4K_COMMON_MAGIC;
-       
+
        /* initialize mips4k specific info */
-       mips32_init_arch_info(target, mips32, chain_pos, variant);
+       mips32_init_arch_info(target, mips32, tap, variant);
        mips32->arch_info = mips_m4k;
-               
+
        return ERROR_OK;
 }
 
-int mips_m4k_target_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc, struct target_s *target)
+int mips_m4k_target_create(struct target_s *target, Jim_Interp *interp)
 {
-       int chain_pos;
-       char *variant = NULL;
-       mips_m4k_common_t *mips_m4k = malloc(sizeof(mips_m4k_common_t));
-       
-       if (argc < 4)
-       {
-               LOG_ERROR("'target mips4k' requires at least one additional argument");
-               exit(-1);
-       }
-       
-       chain_pos = strtoul(args[3], NULL, 0);
-       
-       if (argc >= 5)
-               variant = args[4];
-       
-       mips_m4k_init_arch_info(target, mips_m4k, chain_pos, variant);
-       
+       mips_m4k_common_t *mips_m4k = calloc(1,sizeof(mips_m4k_common_t));
+
+       mips_m4k_init_arch_info(target, mips_m4k, target->tap, target->variant);
+
        return ERROR_OK;
 }
 
@@ -616,23 +772,27 @@ int mips_m4k_examine(struct target_s *target)
        mips32_common_t *mips32 = target->arch_info;
        mips_ejtag_t *ejtag_info = &mips32->ejtag_info;
        u32 idcode = 0;
-       
-       target->type->examined = 1;
-       
-       mips_ejtag_get_idcode(ejtag_info, &idcode, NULL);
-       
-       if (((idcode >> 1) & 0x7FF) == 0x29)
-       {
-               /* we are using a pic32mx so select ejtag port
-                * as it is not selected by default */
-               mips_ejtag_set_instr(ejtag_info, 0x05, NULL);
-               LOG_DEBUG("PIC32MX Detected - using EJTAG Interface");
-       }
-       
+
+       if (!target->type->examined)
+       {
+               mips_ejtag_get_idcode(ejtag_info, &idcode, NULL);
+
+               if (((idcode >> 1) & 0x7FF) == 0x29)
+               {
+                       /* we are using a pic32mx so select ejtag port
+                        * as it is not selected by default */
+                       mips_ejtag_set_instr(ejtag_info, 0x05, NULL);
+                       LOG_DEBUG("PIC32MX Detected - using EJTAG Interface");
+               }
+       }
+
        /* init rest of ejtag interface */
        if ((retval = mips_ejtag_init(ejtag_info)) != ERROR_OK)
                return retval;
-       
+
+       if ((retval = mips32_examine(target)) != ERROR_OK)
+               return retval;
+
        return ERROR_OK;
 }