openocd: fix SPDX tag format for files .c
[fw/openocd] / src / target / mips32_pracc.c
index 21a788f6452a48f9ae9f48fc5fce41b909979a66..c4704b5a5d90f68e424df1d046da23a7cc5746c3 100644 (file)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
 /***************************************************************************
  *   Copyright (C) 2008 by Spencer Oliver                                  *
  *   spen@spen-soft.co.uk                                                  *
  *                                                                         *
  *   Copyright (C) 2008 by David T.L. Wong                                 *
  *                                                                         *
- *   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     *
- *   (at your option) any later version.                                   *
- *                                                                         *
- *   This program is distributed in the hope that it will be useful,       *
- *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
- *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
- *   GNU General Public License for more details.                          *
+ *   Copyright (C) 2009 by David N. Claffey <dnclaffey@gmail.com>          *
  *                                                                         *
- *   You should have received a copy of the GNU General Public License     *
- *   along with this program; if not, write to the                         *
- *   Free Software Foundation, Inc.,                                       *
- *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
+ *   Copyright (C) 2011 by Drasko DRASKOVIC                                *
+ *   drasko.draskovic@gmail.com                                            *
  ***************************************************************************/
 
 /*
-This version has optimized assembly routines for 32 bit operations:
-- read word
-- write word
-- write array of words
-
-One thing to be aware of is that the MIPS32 cpu will execute the 
-instruction after a branch instruction (one delay slot).
-
-For example:
-
-
-    LW $2, ($5 +10)
-    B foo
-    LW $1, ($2 +100)
-
-The LW $1, ($2 +100) instruction is also executed. If this is 
-not wanted a NOP can be inserted:
-
-    LW $2, ($5 +10)
-    B foo
-    NOP
-    LW $1, ($2 +100)
-
-or the code can be changed to:
-
-    B foo
-    LW $2, ($5 +10)
-    LW $1, ($2 +100)
-
-The original code contained NOPs. I have removed these and moved
-the branches.
-
-I also moved the PRACC_STACK to 0xFF204000. This allows
-the use of 16 bits offsets to get pointers to the input
-and output area relative to the stack. Note that the stack
-isn't really a stack (the stack pointer is not 'moving')
-but a FIFO simulated in software.
-
-These changes result in a 35% speed increase when programming an
-external flash.
-
-More improvement could be gained if the registers do no need
-to be preserved but in that case the routines should be aware
-OpenOCD is used as a flash programmer or as a debug tool.
-
-Nico Coesel
-*/
-
+ * This version has optimized assembly routines for 32 bit operations:
+ * - read word
+ * - write word
+ * - write array of words
+ *
+ * One thing to be aware of is that the MIPS32 cpu will execute the
+ * instruction after a branch instruction (one delay slot).
+ *
+ * For example:
+ *  LW $2, ($5 +10)
+ *  B foo
+ *  LW $1, ($2 +100)
+ *
+ * The LW $1, ($2 +100) instruction is also executed. If this is
+ * not wanted a NOP can be inserted:
+ *
+ *  LW $2, ($5 +10)
+ *  B foo
+ *  NOP
+ *  LW $1, ($2 +100)
+ *
+ * or the code can be changed to:
+ *
+ *  B foo
+ *  LW $2, ($5 +10)
+ *  LW $1, ($2 +100)
+ *
+ * The original code contained NOPs. I have removed these and moved
+ * the branches.
+ *
+ * These changes result in a 35% speed increase when programming an
+ * external flash.
+ *
+ * More improvement could be gained if the registers do no need
+ * to be preserved but in that case the routines should be aware
+ * OpenOCD is used as a flash programmer or as a debug tool.
+ *
+ * Nico Coesel
+ */
 
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
+#include <helper/align.h>
+#include <helper/time_support.h>
+#include <jtag/adapter.h>
+
 #include "mips32.h"
 #include "mips32_pracc.h"
 
-typedef struct {
-       uint32_t *local_iparam;
-       int num_iparam;
-       uint32_t *local_oparam;
-       int num_oparam;
-       uint32_t *code;
-       int code_len;
-       uint32_t stack[32];
-       int stack_offset;
-       mips_ejtag_t *ejtag_info;
-} mips32_pracc_context;
-
-static int wait_for_pracc_rw(mips_ejtag_t *ejtag_info, uint32_t *ctrl)
+static int wait_for_pracc_rw(struct mips_ejtag *ejtag_info)
 {
-       uint32_t ejtag_ctrl;
-       
-       while (1) 
-       {
-               mips_ejtag_set_instr(ejtag_info, EJTAG_INST_CONTROL, NULL);
-               ejtag_ctrl = ejtag_info->ejtag_ctrl;
-               mips_ejtag_drscan_32(ejtag_info, &ejtag_ctrl);
-               if (ejtag_ctrl & EJTAG_CTRL_PRACC)
+       int64_t then = timeval_ms();
+
+       /* wait for the PrAcc to become "1" */
+       mips_ejtag_set_instr(ejtag_info, EJTAG_INST_CONTROL);
+
+       while (1) {
+               ejtag_info->pa_ctrl = ejtag_info->ejtag_ctrl;
+               int retval = mips_ejtag_drscan_32(ejtag_info, &ejtag_info->pa_ctrl);
+               if (retval != ERROR_OK)
+                       return retval;
+
+               if (ejtag_info->pa_ctrl & EJTAG_CTRL_PRACC)
                        break;
-               LOG_DEBUG("DEBUGMODULE: No memory access in progress!\n");
-               return ERROR_JTAG_DEVICE_ERROR;
+
+               int64_t timeout = timeval_ms() - then;
+               if (timeout > 1000) {
+                       LOG_DEBUG("DEBUGMODULE: No memory access in progress!");
+                       return ERROR_JTAG_DEVICE_ERROR;
+               }
        }
-       
-       *ctrl = ejtag_ctrl;
+
        return ERROR_OK;
 }
 
-static int mips32_pracc_exec_read(mips32_pracc_context *ctx, uint32_t address)
+/* Shift in control and address for a new processor access, save them in ejtag_info */
+static int mips32_pracc_read_ctrl_addr(struct mips_ejtag *ejtag_info)
 {
-       mips_ejtag_t *ejtag_info = ctx->ejtag_info;
-       int offset;
-       uint32_t ejtag_ctrl, data;
-
-       if ((address >= MIPS32_PRACC_PARAM_IN)
-               && (address <= MIPS32_PRACC_PARAM_IN + ctx->num_iparam * 4))
-       {
-               offset = (address - MIPS32_PRACC_PARAM_IN) / 4;
-               data = ctx->local_iparam[offset];
-       }
-       else if ((address >= MIPS32_PRACC_PARAM_OUT)
-               && (address <= MIPS32_PRACC_PARAM_OUT + ctx->num_oparam * 4))
-       {
-               offset = (address - MIPS32_PRACC_PARAM_OUT) / 4;
-               data = ctx->local_oparam[offset];
-       }
-       else if ((address >= MIPS32_PRACC_TEXT)
-               && (address <= MIPS32_PRACC_TEXT + ctx->code_len*4))
-       {
-               offset = (address - MIPS32_PRACC_TEXT) / 4;
-               data = ctx->code[offset];
-       }
-       else if (address == MIPS32_PRACC_STACK)
-       {
-               /* save to our debug stack */
-               data = ctx->stack[--ctx->stack_offset];
-       }
-       else
-       {
-               /* TODO: send JMP 0xFF200000 instruction. Hopefully processor jump back
-                * to start of debug vector */
-               
-               data = 0;
-               LOG_ERROR("Error reading unexpected address %8.8" PRIx32 "", address);
-               return ERROR_JTAG_DEVICE_ERROR;
-       }
-       
-       /* Send the data out */
-       mips_ejtag_set_instr(ctx->ejtag_info, EJTAG_INST_DATA, NULL);
-       mips_ejtag_drscan_32(ctx->ejtag_info, &data);
-
-       /* Clear the access pending bit (let the processor eat!) */
+       int retval = wait_for_pracc_rw(ejtag_info);
+       if (retval != ERROR_OK)
+               return retval;
 
-       ejtag_ctrl = ejtag_info->ejtag_ctrl & ~EJTAG_CTRL_PRACC;
-       mips_ejtag_set_instr(ctx->ejtag_info, EJTAG_INST_CONTROL, NULL);
-       mips_ejtag_drscan_32(ctx->ejtag_info, &ejtag_ctrl);
+       mips_ejtag_set_instr(ejtag_info, EJTAG_INST_ADDRESS);
 
-       jtag_add_clocks(5);
-       jtag_execute_queue();
-       
+       ejtag_info->pa_addr = 0;
+       return  mips_ejtag_drscan_32(ejtag_info, &ejtag_info->pa_addr);
+}
 
-       return ERROR_OK;
+/* Finish processor access */
+static void mips32_pracc_finish(struct mips_ejtag *ejtag_info)
+{
+       uint32_t ctrl = ejtag_info->ejtag_ctrl & ~EJTAG_CTRL_PRACC;
+       mips_ejtag_set_instr(ejtag_info, EJTAG_INST_CONTROL);
+       mips_ejtag_drscan_32_out(ejtag_info, ctrl);
 }
 
-static int mips32_pracc_exec_write(mips32_pracc_context *ctx, uint32_t address)
+static int mips32_pracc_clean_text_jump(struct mips_ejtag *ejtag_info)
 {
-       uint32_t ejtag_ctrl,data;
-       int offset;
-       mips_ejtag_t *ejtag_info = ctx->ejtag_info;
-
-       mips_ejtag_set_instr(ctx->ejtag_info, EJTAG_INST_DATA, NULL);
-       mips_ejtag_drscan_32(ctx->ejtag_info, &data);
-       
-       /* Clear access pending bit */
-       ejtag_ctrl = ejtag_info->ejtag_ctrl & ~EJTAG_CTRL_PRACC;
-       mips_ejtag_set_instr(ctx->ejtag_info, EJTAG_INST_CONTROL, NULL);
-       mips_ejtag_drscan_32(ctx->ejtag_info, &ejtag_ctrl);
-
-       jtag_add_clocks(5);
-       jtag_execute_queue();
-       
-       if ((address >= MIPS32_PRACC_PARAM_IN)
-               && (address <= MIPS32_PRACC_PARAM_IN + ctx->num_iparam * 4))
-       {
-               offset = (address - MIPS32_PRACC_PARAM_IN) / 4;
-               ctx->local_iparam[offset] = data;
-       }
-       else if ((address >= MIPS32_PRACC_PARAM_OUT )
-               && (address <= MIPS32_PRACC_PARAM_OUT + ctx->num_oparam * 4))
-       {
-               offset = (address - MIPS32_PRACC_PARAM_OUT) / 4;
-               ctx->local_oparam[offset] = data;
-       }
-       else if (address == MIPS32_PRACC_STACK)
-       {
-               /* save data onto our stack */
-               ctx->stack[ctx->stack_offset++] = data;
+       uint32_t jt_code = MIPS32_J(ejtag_info->isa, MIPS32_PRACC_TEXT);
+       pracc_swap16_array(ejtag_info, &jt_code, 1);
+       /* do 3 0/nops to clean pipeline before a jump to pracc text, NOP in delay slot */
+       for (int i = 0; i != 5; i++) {
+               /* Wait for pracc */
+               int retval = wait_for_pracc_rw(ejtag_info);
+               if (retval != ERROR_OK)
+                       return retval;
+
+               /* Data or instruction out */
+               mips_ejtag_set_instr(ejtag_info, EJTAG_INST_DATA);
+               uint32_t data = (i == 3) ? jt_code : MIPS32_NOP;
+               mips_ejtag_drscan_32_out(ejtag_info, data);
+
+               /* finish pa */
+               mips32_pracc_finish(ejtag_info);
        }
-       else
-       {
-               LOG_ERROR("Error writing unexpected address %8.8" PRIx32 "", address);
-               return ERROR_JTAG_DEVICE_ERROR;
+
+       if (ejtag_info->mode != 0)      /* async mode support only for MIPS ... */
+               return ERROR_OK;
+
+       for (int i = 0; i != 2; i++) {
+               int retval = mips32_pracc_read_ctrl_addr(ejtag_info);
+               if (retval != ERROR_OK)
+                       return retval;
+
+               if (ejtag_info->pa_addr != MIPS32_PRACC_TEXT) { /* LEXRA/BMIPS ?, shift out another NOP, max 2 */
+                       mips_ejtag_set_instr(ejtag_info, EJTAG_INST_DATA);
+                       mips_ejtag_drscan_32_out(ejtag_info, MIPS32_NOP);
+                       mips32_pracc_finish(ejtag_info);
+               } else
+                       break;
        }
-       
+
        return ERROR_OK;
 }
 
-int mips32_pracc_exec( mips_ejtag_t *ejtag_info, int code_len, uint32_t *code, int num_param_in, uint32_t *param_in, int num_param_out, uint32_t *param_out, int cycle)
+static int mips32_pracc_exec(struct mips_ejtag *ejtag_info, struct pracc_queue_info *ctx,
+                                       uint32_t *param_out, bool check_last)
 {
-       uint32_t ejtag_ctrl;
-       uint32_t address, data;
-       mips32_pracc_context ctx;
+       int code_count = 0;
+       int store_pending = 0;          /* increases with every store instr at dmseg, decreases with every store pa */
+       uint32_t max_store_addr = 0;    /* for store pa address testing */
+       bool restart = 0;               /* restarting control */
+       int restart_count = 0;
+       uint32_t instr = 0;
+       bool final_check = 0;           /* set to 1 if in final checks after function code shifted out */
+       bool pass = 0;                  /* to check the pass through pracc text after function code sent */
        int retval;
-       int pass = 0;
-       
-       ctx.local_iparam = param_in;
-       ctx.local_oparam = param_out;
-       ctx.num_iparam = num_param_in;
-       ctx.num_oparam = num_param_out;
-       ctx.code = code;
-       ctx.code_len = code_len;
-       ctx.ejtag_info = ejtag_info;
-       ctx.stack_offset = 0;
-       
-       while (1)
-       {
-               if ((retval = wait_for_pracc_rw(ejtag_info, &ejtag_ctrl)) != ERROR_OK)
-                       return retval;
-               
-               address = data = 0;
-               mips_ejtag_set_instr(ejtag_info, EJTAG_INST_ADDRESS, NULL);
-               mips_ejtag_drscan_32(ejtag_info, &address);
-
-//             printf("Adres: %.8x\n", address);
-               
-               /* Check for read or write */
-               if (ejtag_ctrl & EJTAG_CTRL_PRNW)
-               {
-                       if ((retval = mips32_pracc_exec_write(&ctx, address)) != ERROR_OK)
-                               return retval;
+
+       while (1) {
+               if (restart) {
+                       if (restart_count < 3) {                                        /* max 3 restarts allowed */
+                               retval = mips32_pracc_clean_text_jump(ejtag_info);
+                               if (retval != ERROR_OK)
+                                       return retval;
+                       } else
+                               return ERROR_JTAG_DEVICE_ERROR;
+                       restart_count++;
+                       restart = 0;
+                       code_count = 0;
+                       LOG_DEBUG("restarting code");
                }
-               else
-               {
-                       /* Check to see if its reading at the debug vector. The first pass through
-                        * the module is always read at the vector, so the first one we allow.  When
-                        * the second read from the vector occurs we are done and just exit. */
-                       if ((address == MIPS32_PRACC_TEXT) && (pass++))
-                       {
-                               break;
+
+               retval = mips32_pracc_read_ctrl_addr(ejtag_info); /* update current pa info: control and address */
+               if (retval != ERROR_OK)
+                       return retval;
+
+               /* Check for read or write access */
+               if (ejtag_info->pa_ctrl & EJTAG_CTRL_PRNW) {                            /* write/store access */
+                       /* Check for pending store from a previous store instruction at dmseg */
+                       if (store_pending == 0) {
+                               LOG_DEBUG("unexpected write at address %" PRIx32, ejtag_info->pa_addr);
+                               if (code_count < 2) {   /* allow for restart */
+                                       restart = 1;
+                                       continue;
+                               } else
+                                       return ERROR_JTAG_DEVICE_ERROR;
+                       } else {
+                               /* check address */
+                               if (ejtag_info->pa_addr < MIPS32_PRACC_PARAM_OUT ||
+                                               ejtag_info->pa_addr > max_store_addr) {
+                                       LOG_DEBUG("writing at unexpected address %" PRIx32, ejtag_info->pa_addr);
+                                       return ERROR_JTAG_DEVICE_ERROR;
+                               }
                        }
-                       
-                       if ((retval = mips32_pracc_exec_read(&ctx, address)) != ERROR_OK)
+                       /* read data */
+                       uint32_t data = 0;
+                       mips_ejtag_set_instr(ejtag_info, EJTAG_INST_DATA);
+                       retval = mips_ejtag_drscan_32(ejtag_info, &data);
+                       if (retval != ERROR_OK)
                                return retval;
 
+                       /* store data at param out, address based offset */
+                       param_out[(ejtag_info->pa_addr - MIPS32_PRACC_PARAM_OUT) / 4] = data;
+                       store_pending--;
+
+               } else {                                        /* read/fetch access */
+                        if (!final_check) {                    /* executing function code */
+                               /* check address */
+                               if (ejtag_info->pa_addr != (MIPS32_PRACC_TEXT + code_count * 4)) {
+                                       LOG_DEBUG("reading at unexpected address %" PRIx32 ", expected %x",
+                                                       ejtag_info->pa_addr, MIPS32_PRACC_TEXT + code_count * 4);
+
+                                       /* restart code execution only in some cases */
+                                       if (code_count == 1 && ejtag_info->pa_addr == MIPS32_PRACC_TEXT &&
+                                                                               restart_count == 0) {
+                                               LOG_DEBUG("restarting, without clean jump");
+                                               restart_count++;
+                                               code_count = 0;
+                                               continue;
+                                       } else if (code_count < 2) {
+                                               restart = 1;
+                                               continue;
+                                       }
+                                       return ERROR_JTAG_DEVICE_ERROR;
+                               }
+                               /* check for store instruction at dmseg */
+                               uint32_t store_addr = ctx->pracc_list[code_count].addr;
+                               if (store_addr != 0) {
+                                       if (store_addr > max_store_addr)
+                                               max_store_addr = store_addr;
+                                       store_pending++;
+                               }
+
+                               instr = ctx->pracc_list[code_count++].instr;
+                               if (code_count == ctx->code_count)      /* last instruction, start final check */
+                                       final_check = 1;
+
+                        } else {       /* final check after function code shifted out */
+                                       /* check address */
+                               if (ejtag_info->pa_addr == MIPS32_PRACC_TEXT) {
+                                       if (!pass) {    /* first pass through pracc text */
+                                               if (store_pending == 0)         /* done, normal exit */
+                                                       return ERROR_OK;
+                                               pass = 1;               /* pracc text passed */
+                                               code_count = 0;         /* restart code count */
+                                       } else {
+                                               LOG_DEBUG("unexpected second pass through pracc text");
+                                               return ERROR_JTAG_DEVICE_ERROR;
+                                       }
+                               } else {
+                                       if (ejtag_info->pa_addr != (MIPS32_PRACC_TEXT + code_count * 4)) {
+                                               LOG_DEBUG("unexpected read address in final check: %"
+                                                       PRIx32 ", expected: %x", ejtag_info->pa_addr,
+                                                       MIPS32_PRACC_TEXT + code_count * 4);
+                                               return ERROR_JTAG_DEVICE_ERROR;
+                                       }
+                               }
+                               if (!pass) {
+                                       if ((code_count - ctx->code_count) > 1) { /* allow max 2 instr delay slot */
+                                               LOG_DEBUG("failed to jump back to pracc text");
+                                               return ERROR_JTAG_DEVICE_ERROR;
+                                       }
+                               } else
+                                       if (code_count > 10) {          /* enough, abandon */
+                                               LOG_DEBUG("execution abandoned, store pending: %d", store_pending);
+                                               return ERROR_JTAG_DEVICE_ERROR;
+                                       }
+                               instr = MIPS32_NOP;     /* shift out NOPs instructions */
+                               code_count++;
+                        }
+
+                       /* Send instruction out */
+                       mips_ejtag_set_instr(ejtag_info, EJTAG_INST_DATA);
+                       mips_ejtag_drscan_32_out(ejtag_info, instr);
+               }
+               /* finish processor access, let the processor eat! */
+               mips32_pracc_finish(ejtag_info);
+
+               if (final_check && !check_last)                 /* last instr, don't check, execute and exit */
+                       return jtag_execute_queue();
+
+               if (store_pending == 0 && pass) {       /* store access done, but after passing pracc text */
+                       LOG_DEBUG("warning: store access pass pracc text");
+                       return ERROR_OK;
                }
-               
-               if (cycle == 0)
-                       break;
-       }
-       
-       /* stack sanity check */
-       if (ctx.stack_offset != 0)
-       {
-               LOG_DEBUG("Pracc Stack not zero");
        }
-       
-       return ERROR_OK;
 }
 
-int mips32_pracc_read_mem(mips_ejtag_t *ejtag_info, uint32_t addr, int size, int count, void *buf)
+inline void pracc_queue_init(struct pracc_queue_info *ctx)
 {
-       switch (size)
-       {
-               case 1:
-                       return mips32_pracc_read_mem8(ejtag_info, addr, count, (uint8_t*)buf);
-               case 2:
-                       return mips32_pracc_read_mem16(ejtag_info, addr, count, (uint16_t*)buf);
-               case 4:
-                       if (count == 1)
-                               return mips32_pracc_read_u32(ejtag_info, addr, (uint32_t*)buf);
-                       else
-                               return mips32_pracc_read_mem32(ejtag_info, addr, count, (uint32_t*)buf);
-       }
-       
-       return ERROR_OK;
+       ctx->retval = ERROR_OK;
+       ctx->code_count = 0;
+       ctx->store_count = 0;
+       ctx->max_code = 0;
+       ctx->pracc_list = NULL;
+       ctx->isa = ctx->ejtag_info->isa ? 1 : 0;
 }
 
-int mips32_pracc_read_mem32(mips_ejtag_t *ejtag_info, uint32_t addr, int count, uint32_t *buf)
-{      
-       uint32_t code[] = {
-                                                                                                                       /* start: */
-               MIPS32_MTC0(15,31,0),                                                           /* move $15 to COP0 DeSave */
-               MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)),             /* $15 = MIPS32_PRACC_STACK */
-               MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
-               MIPS32_SW(8,0,15),                                                                      /* sw $8,($15) */
-               MIPS32_SW(9,0,15),                                                                      /* sw $9,($15) */
-               MIPS32_SW(10,0,15),                                                             /* sw $10,($15) */
-               MIPS32_SW(11,0,15),                                                             /* sw $11,($15) */
-                       
-               MIPS32_LUI(8,UPPER16(MIPS32_PRACC_PARAM_IN)),           /* $8 = MIPS32_PRACC_PARAM_IN */
-               MIPS32_ORI(8,8,LOWER16(MIPS32_PRACC_PARAM_IN)),
-               MIPS32_LW(9,0,8),                                                                       /* $9=mem[$8]; read addr */
-               MIPS32_LW(10,4,8),                                                                      /* $10=mem[$8+4]; read count */
-               MIPS32_LUI(11,UPPER16(MIPS32_PRACC_PARAM_OUT)),         /* $11=MIPS32_PRACC_PARAM_OUT */
-               MIPS32_ORI(11,11,LOWER16(MIPS32_PRACC_PARAM_OUT)),
-               MIPS32_NOP,
-                                                                                                                       /* loop: */
-               MIPS32_BEQ(0,10,9),                                                                     /* beq 0, $10, end */
-               MIPS32_NOP,
-               
-               MIPS32_LW(8,0,9),                                                                       /* lw $8,0($9), Load $8 with the word @mem[$9] */
-               MIPS32_SW(8,0,11),                                                                      /* sw $8,0($11) */
-               
-               MIPS32_ADDI(10,10,NEG16(1)),                                            /* $10-- */
-               MIPS32_ADDI(9,9,4),                                                             /* $1 += 4 */
-               MIPS32_ADDI(11,11,4),                                                           /* $11 += 4 */
-               
-               MIPS32_NOP,
-               MIPS32_B(NEG16(9)),                                                                     /* b loop */
-               MIPS32_NOP,
-                                                                                                                       /* end: */
-               MIPS32_LW(11,0,15),                                                             /* lw $11,($15) */
-               MIPS32_LW(10,0,15),                                                             /* lw $10,($15) */
-               MIPS32_LW(9,0,15),                                                                      /* lw $9,($15) */
-               MIPS32_LW(8,0,15),                                                                      /* lw $8,($15) */
-               MIPS32_MFC0(15,31,0),                                                           /* move COP0 DeSave to $15 */
-               MIPS32_NOP,
-               MIPS32_B(NEG16(31)),                                                            /* b start */
-               MIPS32_NOP,
-       };
-       
-       int retval = ERROR_OK;
-       int blocksize;
-       int bytesread;
-       uint32_t param_in[2];
-       
-       bytesread = 0;
-       
-       while (count > 0)
-       {       
-               blocksize = count;
-               if (count > 0x400)
-                       blocksize = 0x400;
-               
-               param_in[0] = addr;
-               param_in[1] = blocksize;
-               
-               if ((retval = mips32_pracc_exec(ejtag_info, sizeof(code)/sizeof(code[0]), code, 
-                       sizeof(param_in)/sizeof(param_in[0]), param_in, blocksize, &buf[bytesread], 1)) != ERROR_OK)
-               {
-                       return retval;
+void pracc_add(struct pracc_queue_info *ctx, uint32_t addr, uint32_t instr)
+{
+       if (ctx->retval != ERROR_OK)    /* On previous out of memory, return */
+               return;
+       if (ctx->code_count == ctx->max_code) {
+               void *p = realloc(ctx->pracc_list, sizeof(struct pa_list) * (ctx->max_code + PRACC_BLOCK));
+               if (p) {
+                       ctx->max_code += PRACC_BLOCK;
+                       ctx->pracc_list = p;
+               } else {
+                       ctx->retval = ERROR_FAIL;       /* Out of memory */
+                       return;
                }
-               
-               count -= blocksize;
-               addr += blocksize;
-               bytesread += blocksize;
        }
+       ctx->pracc_list[ctx->code_count].instr = instr;
+       ctx->pracc_list[ctx->code_count++].addr = addr;
+       if (addr)
+               ctx->store_count++;
+}
 
-       return retval;
+static void pracc_add_li32(struct pracc_queue_info *ctx, uint32_t reg_num, uint32_t data, bool optimize)
+{
+       if (LOWER16(data) == 0 && optimize)
+               pracc_add(ctx, 0, MIPS32_LUI(ctx->isa, reg_num, UPPER16(data)));        /* load only upper value */
+       else if (UPPER16(data) == 0 && optimize)
+               pracc_add(ctx, 0, MIPS32_ORI(ctx->isa, reg_num, 0, LOWER16(data)));     /* load only lower */
+       else {
+               pracc_add(ctx, 0, MIPS32_LUI(ctx->isa, reg_num, UPPER16(data)));        /* load upper and lower */
+               pracc_add(ctx, 0, MIPS32_ORI(ctx->isa, reg_num, reg_num, LOWER16(data)));
+       }
 }
 
-int mips32_pracc_read_u32(mips_ejtag_t *ejtag_info, uint32_t addr, uint32_t *buf)
+inline void pracc_queue_free(struct pracc_queue_info *ctx)
 {
-       uint32_t code[] = {
-                                                                                                                       /* start: */
-               MIPS32_MTC0(15,31,0),                                                           /* move $15 to COP0 DeSave */
-               MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)),             /* $15 = MIPS32_PRACC_STACK */
-               MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
-               MIPS32_SW(8,0,15),                                                                      /* sw $8,($15) */
-
-               MIPS32_LW(8,NEG16(MIPS32_PRACC_STACK-MIPS32_PRACC_PARAM_IN), 15),  //load R8 @ param_in[0] = address
-
-               MIPS32_LW(8,0,8),                                                                       /* lw $8,0($8), Load $8 with the word @mem[$8] */
-               MIPS32_SW(8,NEG16(MIPS32_PRACC_STACK-MIPS32_PRACC_PARAM_OUT),15),                                                                       /* sw $8,0($9) */
-
-               MIPS32_LW(8,0,15),                                                                      /* lw $8,($15) */
-               MIPS32_B(NEG16(9)),     //was 17                                                        /* b start */
-               MIPS32_MFC0(15,31,0),   //this instruction will be executed (MIPS executes instruction after jump)                                                      /* move COP0 DeSave to $15 */
-               MIPS32_NOP,
-       };
+       free(ctx->pracc_list);
+}
 
-       int retval = ERROR_OK;
-       uint32_t param_in[1];
+int mips32_pracc_queue_exec(struct mips_ejtag *ejtag_info, struct pracc_queue_info *ctx,
+                                       uint32_t *buf, bool check_last)
+{
+       if (ctx->retval != ERROR_OK) {
+               LOG_ERROR("Out of memory");
+               return ERROR_FAIL;
+       }
+
+       if (ejtag_info->isa && ejtag_info->endianness)
+               for (int i = 0; i != ctx->code_count; i++)
+                       ctx->pracc_list[i].instr = SWAP16(ctx->pracc_list[i].instr);
+
+       if (ejtag_info->mode == 0)
+               return mips32_pracc_exec(ejtag_info, ctx, buf, check_last);
+
+       union scan_in {
+               uint8_t scan_96[12];
+               struct {
+                       uint8_t ctrl[4];
+                       uint8_t data[4];
+                       uint8_t addr[4];
+               } scan_32;
+
+       } *scan_in = malloc(sizeof(union scan_in) * (ctx->code_count + ctx->store_count));
+       if (!scan_in) {
+               LOG_ERROR("Out of memory");
+               return ERROR_FAIL;
+       }
 
-       param_in[0] = addr;
+       unsigned num_clocks =
+               ((uint64_t)(ejtag_info->scan_delay) * adapter_get_speed_khz() + 500000) / 1000000;
 
-       if ((retval = mips32_pracc_exec(ejtag_info, sizeof(code)/sizeof(code[0]), code, 
-               sizeof(param_in)/sizeof(param_in[0]), param_in, sizeof(uint32_t), buf, 1)) != ERROR_OK)
-       {
-               return retval;
+       uint32_t ejtag_ctrl = ejtag_info->ejtag_ctrl & ~EJTAG_CTRL_PRACC;
+       mips_ejtag_set_instr(ejtag_info, EJTAG_INST_ALL);
+
+       int scan_count = 0;
+       for (int i = 0; i != ctx->code_count; i++) {
+               jtag_add_clocks(num_clocks);
+               mips_ejtag_add_scan_96(ejtag_info, ejtag_ctrl, ctx->pracc_list[i].instr,
+                                      scan_in[scan_count++].scan_96);
+
+               /* Check store address from previous instruction, if not the first */
+               if (i > 0 && ctx->pracc_list[i - 1].addr) {
+                       jtag_add_clocks(num_clocks);
+                       mips_ejtag_add_scan_96(ejtag_info, ejtag_ctrl, 0, scan_in[scan_count++].scan_96);
+               }
        }
 
+       int retval = jtag_execute_queue();              /* execute queued scans */
+       if (retval != ERROR_OK)
+               goto exit;
+
+       uint32_t fetch_addr = MIPS32_PRACC_TEXT;                /* start address */
+       scan_count = 0;
+       for (int i = 0; i != ctx->code_count; i++) {                            /* verify every pracc access */
+               /* check pracc bit */
+               ejtag_ctrl = buf_get_u32(scan_in[scan_count].scan_32.ctrl, 0, 32);
+               uint32_t addr = buf_get_u32(scan_in[scan_count].scan_32.addr, 0, 32);
+               if (!(ejtag_ctrl & EJTAG_CTRL_PRACC)) {
+                       LOG_ERROR("Error: access not pending  count: %d", scan_count);
+                       retval = ERROR_FAIL;
+                       goto exit;
+               }
+               if (ejtag_ctrl & EJTAG_CTRL_PRNW) {
+                       LOG_ERROR("Not a fetch/read access, count: %d", scan_count);
+                       retval = ERROR_FAIL;
+                       goto exit;
+               }
+               if (addr != fetch_addr) {
+                       LOG_ERROR("Fetch addr mismatch, read: %" PRIx32 " expected: %" PRIx32 " count: %d",
+                                         addr, fetch_addr, scan_count);
+                       retval = ERROR_FAIL;
+                       goto exit;
+               }
+               fetch_addr += 4;
+               scan_count++;
+
+               /* check if previous instruction is a store instruction at dmesg */
+               if (i > 0 && ctx->pracc_list[i - 1].addr) {
+                       uint32_t store_addr = ctx->pracc_list[i - 1].addr;
+                       ejtag_ctrl = buf_get_u32(scan_in[scan_count].scan_32.ctrl, 0, 32);
+                       addr = buf_get_u32(scan_in[scan_count].scan_32.addr, 0, 32);
+
+                       if (!(ejtag_ctrl & EJTAG_CTRL_PRNW)) {
+                               LOG_ERROR("Not a store/write access, count: %d", scan_count);
+                               retval = ERROR_FAIL;
+                               goto exit;
+                       }
+                       if (addr != store_addr) {
+                               LOG_ERROR("Store address mismatch, read: %" PRIx32 " expected: %" PRIx32 " count: %d",
+                                                             addr, store_addr, scan_count);
+                               retval = ERROR_FAIL;
+                               goto exit;
+                       }
+                       int buf_index = (addr - MIPS32_PRACC_PARAM_OUT) / 4;
+                       buf[buf_index] = buf_get_u32(scan_in[scan_count].scan_32.data, 0, 32);
+                       scan_count++;
+               }
+       }
+exit:
+       free(scan_in);
        return retval;
 }
 
-int mips32_pracc_read_mem16(mips_ejtag_t *ejtag_info, uint32_t addr, int count, uint16_t *buf)
+static int mips32_pracc_read_u32(struct mips_ejtag *ejtag_info, uint32_t addr, uint32_t *buf)
 {
-       uint32_t code[] = {
-                                                                                                                       /* start: */
-               MIPS32_MTC0(15,31,0),                                                           /* move $15 to COP0 DeSave */
-               MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)),             /* $15 = MIPS32_PRACC_STACK */
-               MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
-               MIPS32_SW(8,0,15),                                                                      /* sw $8,($15) */
-               MIPS32_SW(9,0,15),                                                                      /* sw $9,($15) */
-               MIPS32_SW(10,0,15),                                                             /* sw $10,($15) */
-               MIPS32_SW(11,0,15),                                                             /* sw $11,($15) */
-                       
-               MIPS32_LUI(8,UPPER16(MIPS32_PRACC_PARAM_IN)),           /* $8 = MIPS32_PRACC_PARAM_IN */
-               MIPS32_ORI(8,8,LOWER16(MIPS32_PRACC_PARAM_IN)),
-               MIPS32_LW(9,0,8),                                                                       /* $9=mem[$8]; read addr */
-               MIPS32_LW(10,4,8),                                                                      /* $10=mem[$8+4]; read count */
-               MIPS32_LUI(11,UPPER16(MIPS32_PRACC_PARAM_OUT)),         /* $11=MIPS32_PRACC_PARAM_OUT */
-               MIPS32_ORI(11,11,LOWER16(MIPS32_PRACC_PARAM_OUT)),
-               MIPS32_NOP,
-                                                                                                                       /* loop: */
-               MIPS32_BEQ(0,10,9),                                                             /* beq 0, $10, end */
-               MIPS32_NOP,
-               
-               MIPS32_LHU(8,0,9),                                                                      /* lw $8,0($9), Load $8 with the halfword @mem[$9] */
-               MIPS32_SW(8,0,11),                                                                      /* sw $8,0($11) */
-               
-               MIPS32_ADDI(10,10,NEG16(1)),                                            /* $10-- */
-               MIPS32_ADDI(9,9,2),                                                             /* $9 += 2 */
-               MIPS32_ADDI(11,11,4),                                                           /* $11 += 4 */
-               MIPS32_NOP,
-               MIPS32_B(NEG16(9)),                                                                     /* b loop */
-               MIPS32_NOP,
-
-               MIPS32_LW(11,0,15),                                                             /* lw $11,($15) */
-               MIPS32_LW(10,0,15),                                                             /* lw $10,($15) */
-               MIPS32_LW(9,0,15),                                                                      /* lw $9,($15) */
-               MIPS32_LW(8,0,15),                                                                      /* lw $8,($15) */
-               MIPS32_MFC0(15,31,0),                                                           /* move COP0 DeSave to $15 */
-               MIPS32_NOP,
-               MIPS32_B(NEG16(31)),                                                            /* b start */
-               MIPS32_NOP,
-       };
+       struct pracc_queue_info ctx = {.ejtag_info = ejtag_info};
+       pracc_queue_init(&ctx);
+
+       pracc_add(&ctx, 0, MIPS32_LUI(ctx.isa, 15, PRACC_UPPER_BASE_ADDR));     /* $15 = MIPS32_PRACC_BASE_ADDR */
+       pracc_add(&ctx, 0, MIPS32_LUI(ctx.isa, 8, UPPER16((addr + 0x8000)))); /* load  $8 with modified upper addr */
+       pracc_add(&ctx, 0, MIPS32_LW(ctx.isa, 8, LOWER16(addr), 8));                    /* lw $8, LOWER16(addr)($8) */
+       pracc_add(&ctx, MIPS32_PRACC_PARAM_OUT,
+                               MIPS32_SW(ctx.isa, 8, PRACC_OUT_OFFSET, 15));   /* sw $8,PRACC_OUT_OFFSET($15) */
+       pracc_add_li32(&ctx, 8, ejtag_info->reg8, 0);                           /* restore $8 */
+       pracc_add(&ctx, 0, MIPS32_B(ctx.isa, NEG16((ctx.code_count + 1) << ctx.isa)));          /* jump to start */
+       pracc_add(&ctx, 0, MIPS32_MFC0(ctx.isa, 15, 31, 0));                            /* move COP0 DeSave to $15 */
+
+       ctx.retval = mips32_pracc_queue_exec(ejtag_info, &ctx, buf, 1);
+       pracc_queue_free(&ctx);
+       return ctx.retval;
+}
 
-//     /* TODO remove array */
-       uint32_t param_out[count];
-       int i;
-       
-//     int retval;
-       int blocksize;
-       int bytesread;
-       uint32_t param_in[2];
-       
-       bytesread = 0;
-       
-       //while (count > 0)
-       {       
-               blocksize = count;
-               if (count > 0x400)
-                       blocksize = 0x400;
-               
-               param_in[0] = addr;
-               param_in[1] = blocksize;
-               
-               mips32_pracc_exec(ejtag_info, sizeof(code)/sizeof(code[0]), code, \
-                       sizeof(param_in)/sizeof(param_in[0]), param_in, count, param_out, 1);
-               
-//             count -= blocksize;
-//             addr += blocksize;
-//             bytesread += blocksize;
+int mips32_pracc_read_mem(struct mips_ejtag *ejtag_info, uint32_t addr, int size, int count, void *buf)
+{
+       if (count == 1 && size == 4)
+               return mips32_pracc_read_u32(ejtag_info, addr, (uint32_t *)buf);
+
+       struct pracc_queue_info ctx = {.ejtag_info = ejtag_info};
+       pracc_queue_init(&ctx);
+
+       uint32_t *data = NULL;
+       if (size != 4) {
+               data = malloc(256 * sizeof(uint32_t));
+               if (!data) {
+                       LOG_ERROR("Out of memory");
+                       goto exit;
+               }
        }
-       
-       for (i = 0; i < count; i++)
-       {
-               buf[i] = param_out[i];
+
+       uint32_t *buf32 = buf;
+       uint16_t *buf16 = buf;
+       uint8_t *buf8 = buf;
+
+       while (count) {
+               ctx.code_count = 0;
+               ctx.store_count = 0;
+
+               int this_round_count = (count > 256) ? 256 : count;
+               uint32_t last_upper_base_addr = UPPER16((addr + 0x8000));
+
+               pracc_add(&ctx, 0, MIPS32_LUI(ctx.isa, 15, PRACC_UPPER_BASE_ADDR)); /* $15 = MIPS32_PRACC_BASE_ADDR */
+               pracc_add(&ctx, 0, MIPS32_LUI(ctx.isa, 9, last_upper_base_addr));       /* upper memory addr to $9 */
+
+               for (int i = 0; i != this_round_count; i++) {                   /* Main code loop */
+                       uint32_t upper_base_addr = UPPER16((addr + 0x8000));
+                       if (last_upper_base_addr != upper_base_addr) {  /* if needed, change upper addr in $9 */
+                               pracc_add(&ctx, 0, MIPS32_LUI(ctx.isa, 9, upper_base_addr));
+                               last_upper_base_addr = upper_base_addr;
+                       }
+
+                       if (size == 4)                          /* load from memory to $8 */
+                               pracc_add(&ctx, 0, MIPS32_LW(ctx.isa, 8, LOWER16(addr), 9));
+                       else if (size == 2)
+                               pracc_add(&ctx, 0, MIPS32_LHU(ctx.isa, 8, LOWER16(addr), 9));
+                       else
+                               pracc_add(&ctx, 0, MIPS32_LBU(ctx.isa, 8, LOWER16(addr), 9));
+
+                       pracc_add(&ctx, MIPS32_PRACC_PARAM_OUT + i * 4,                 /* store $8 at param out */
+                                         MIPS32_SW(ctx.isa, 8, PRACC_OUT_OFFSET + i * 4, 15));
+                       addr += size;
+               }
+               pracc_add_li32(&ctx, 8, ejtag_info->reg8, 0);                           /* restore $8 */
+               pracc_add_li32(&ctx, 9, ejtag_info->reg9, 0);                           /* restore $9 */
+
+               pracc_add(&ctx, 0, MIPS32_B(ctx.isa, NEG16((ctx.code_count + 1) << ctx.isa)));  /* jump to start */
+               pracc_add(&ctx, 0, MIPS32_MFC0(ctx.isa, 15, 31, 0));                    /* restore $15 from DeSave */
+
+               if (size == 4) {
+                       ctx.retval = mips32_pracc_queue_exec(ejtag_info, &ctx, buf32, 1);
+                       if (ctx.retval != ERROR_OK)
+                               goto exit;
+                       buf32 += this_round_count;
+               } else {
+                       ctx.retval = mips32_pracc_queue_exec(ejtag_info, &ctx, data, 1);
+                       if (ctx.retval != ERROR_OK)
+                               goto exit;
+
+                       uint32_t *data_p = data;
+                       for (int i = 0; i != this_round_count; i++) {
+                               if (size == 2)
+                                       *buf16++ = *data_p++;
+                               else
+                                       *buf8++ = *data_p++;
+                       }
+               }
+               count -= this_round_count;
        }
-       
-       return ERROR_OK;
+exit:
+       pracc_queue_free(&ctx);
+       free(data);
+       return ctx.retval;
 }
 
-int mips32_pracc_read_mem8(mips_ejtag_t *ejtag_info, uint32_t addr, int count, uint8_t *buf)
+int mips32_cp0_read(struct mips_ejtag *ejtag_info, uint32_t *val, uint32_t cp0_reg, uint32_t cp0_sel)
 {
-       uint32_t code[] = {
-                                                                                                                       /* start: */
-               MIPS32_MTC0(15,31,0),                                                           /* move $15 to COP0 DeSave */
-               MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)),             /* $15 = MIPS32_PRACC_STACK */
-               MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
-               MIPS32_SW(8,0,15),                                                                      /* sw $8,($15) */
-               MIPS32_SW(9,0,15),                                                                      /* sw $9,($15) */
-               MIPS32_SW(10,0,15),                                                             /* sw $10,($15) */
-               MIPS32_SW(11,0,15),                                                             /* sw $11,($15) */
-                       
-               MIPS32_LUI(8,UPPER16(MIPS32_PRACC_PARAM_IN)),           /* $8 = MIPS32_PRACC_PARAM_IN */
-               MIPS32_ORI(8,8,LOWER16(MIPS32_PRACC_PARAM_IN)),
-               MIPS32_LW(9,0,8),                                                                       /* $9=mem[$8]; read addr */
-               MIPS32_LW(10,4,8),                                                                      /* $10=mem[$8+4]; read count */
-               MIPS32_LUI(11,UPPER16(MIPS32_PRACC_PARAM_OUT)),         /* $11=MIPS32_PRACC_PARAM_OUT */
-               MIPS32_ORI(11,11,LOWER16(MIPS32_PRACC_PARAM_OUT)),
-               MIPS32_NOP,
-                                                                                                                       /* loop: */
-               MIPS32_BEQ(0,10,9),                                                             /* beq 0, $10, end */
-               MIPS32_NOP,
-               
-               MIPS32_LBU(8,0,9),                                                                      /* lw $8,0($9), Load t4 with the byte @mem[t1] */
-               MIPS32_SW(8,0,11),                                                                      /* sw $8,0($11) */
-               
-               MIPS32_ADDI(10,10,NEG16(1)),                                            /* $10-- */
-               MIPS32_ADDI(9,9,1),                                                             /* $9 += 1 */
-               MIPS32_ADDI(11,11,4),                                                           /* $11 += 4 */
-               MIPS32_NOP,
-               MIPS32_B(NEG16(9)),                                                                     /* b loop */
-               MIPS32_NOP,
-                                                                                                                       /* end: */
-               MIPS32_LW(11,0,15),                                                             /* lw $11,($15) */
-               MIPS32_LW(10,0,15),                                                             /* lw $10,($15) */
-               MIPS32_LW(9,0,15),                                                                      /* lw $9,($15) */
-               MIPS32_LW(8,0,15),                                                                      /* lw $8,($15) */
-               MIPS32_MFC0(15,31,0),                                                           /* move COP0 DeSave to $15 */
-               MIPS32_NOP,
-               MIPS32_B(NEG16(31)),                                                            /* b start */
-               MIPS32_NOP,
-       };
-       
-//     /* TODO remove array */
-       uint32_t param_out[count];
-       int i;
-       
-//     int retval;
-       int blocksize;
-       int bytesread;
-       uint32_t param_in[2];
-       
-       bytesread = 0;
-       
-//     while (count > 0)
-       {       
-               blocksize = count;
-               if (count > 0x400)
-                       blocksize = 0x400;
-               
-               param_in[0] = addr;
-               param_in[1] = blocksize;
-               
-               mips32_pracc_exec(ejtag_info, sizeof(code)/sizeof(code[0]), code, \
-                       sizeof(param_in)/sizeof(param_in[0]), param_in, count, param_out, 1);
-               
-//             count -= blocksize;
-//             addr += blocksize;
-//             bytesread += blocksize;
-       }
-       
-       for (i = 0; i < count; i++)
-       {
-               buf[i] = param_out[i];
-       }
+       struct pracc_queue_info ctx = {.ejtag_info = ejtag_info};
+       pracc_queue_init(&ctx);
+
+       pracc_add(&ctx, 0, MIPS32_LUI(ctx.isa, 15, PRACC_UPPER_BASE_ADDR));     /* $15 = MIPS32_PRACC_BASE_ADDR */
+       pracc_add(&ctx, 0, MIPS32_MFC0(ctx.isa, 8, cp0_reg, cp0_sel));          /* move cp0 reg / sel to $8 */
+       pracc_add(&ctx, MIPS32_PRACC_PARAM_OUT,
+                               MIPS32_SW(ctx.isa, 8, PRACC_OUT_OFFSET, 15));   /* store $8 to pracc_out */
+       pracc_add(&ctx, 0, MIPS32_MFC0(ctx.isa, 15, 31, 0));                            /* restore $15 from DeSave */
+       pracc_add(&ctx, 0, MIPS32_LUI(ctx.isa, 8, UPPER16(ejtag_info->reg8)));  /* restore upper 16 bits  of $8 */
+       pracc_add(&ctx, 0, MIPS32_B(ctx.isa, NEG16((ctx.code_count + 1) << ctx.isa)));          /* jump to start */
+       pracc_add(&ctx, 0, MIPS32_ORI(ctx.isa, 8, 8, LOWER16(ejtag_info->reg8))); /* restore lower 16 bits of $8 */
+
+       ctx.retval = mips32_pracc_queue_exec(ejtag_info, &ctx, val, 1);
+       pracc_queue_free(&ctx);
+       return ctx.retval;
+}
 
-       return ERROR_OK;
+int mips32_cp0_write(struct mips_ejtag *ejtag_info, uint32_t val, uint32_t cp0_reg, uint32_t cp0_sel)
+{
+       struct pracc_queue_info ctx = {.ejtag_info = ejtag_info};
+       pracc_queue_init(&ctx);
+
+       pracc_add_li32(&ctx, 15, val, 0);                               /* Load val to $15 */
+
+       pracc_add(&ctx, 0, MIPS32_MTC0(ctx.isa, 15, cp0_reg, cp0_sel));         /* write $15 to cp0 reg / sel */
+       pracc_add(&ctx, 0, MIPS32_B(ctx.isa, NEG16((ctx.code_count + 1) << ctx.isa)));          /* jump to start */
+       pracc_add(&ctx, 0, MIPS32_MFC0(ctx.isa, 15, 31, 0));                    /* restore $15 from DeSave */
+
+       ctx.retval = mips32_pracc_queue_exec(ejtag_info, &ctx, NULL, 1);
+       pracc_queue_free(&ctx);
+       return ctx.retval;
 }
 
-int mips32_pracc_write_mem(mips_ejtag_t *ejtag_info, uint32_t addr, int size, int count, void *buf)
+/**
+ * \b mips32_pracc_sync_cache
+ *
+ * Synchronize Caches to Make Instruction Writes Effective
+ * (ref. doc. MIPS32 Architecture For Programmers Volume II: The MIPS32 Instruction Set,
+ *  Document Number: MD00086, Revision 2.00, June 9, 2003)
+ *
+ * When the instruction stream is written, the SYNCI instruction should be used
+ * in conjunction with other instructions to make the newly-written instructions effective.
+ *
+ * Explanation :
+ * A program that loads another program into memory is actually writing the D- side cache.
+ * The instructions it has loaded can't be executed until they reach the I-cache.
+ *
+ * After the instructions have been written, the loader should arrange
+ * to write back any containing D-cache line and invalidate any locations
+ * already in the I-cache.
+ *
+ * If the cache coherency attribute (CCA) is set to zero, it's a write through cache, there is no need
+ * to write back.
+ *
+ * In the latest MIPS32/64 CPUs, MIPS provides the synci instruction,
+ * which does the whole job for a cache-line-sized chunk of the memory you just loaded:
+ * That is, it arranges a D-cache write-back (if CCA = 3) and an I-cache invalidate.
+ *
+ * The line size is obtained with the rdhwr SYNCI_Step in release 2 or from cp0 config 1 register in release 1.
+ */
+static int mips32_pracc_synchronize_cache(struct mips_ejtag *ejtag_info,
+                                        uint32_t start_addr, uint32_t end_addr, int cached, int rel)
 {
-       switch (size)
-       {
-               case 1:
-                       return mips32_pracc_write_mem8(ejtag_info, addr, count, (uint8_t*)buf);
-               case 2:
-                       return mips32_pracc_write_mem16(ejtag_info, addr, count,(uint16_t*)buf);
-               case 4:
-                       if (count == 1)
-                               return mips32_pracc_write_u32(ejtag_info, addr, (uint32_t*)buf);
-                       else
-                               return mips32_pracc_write_mem32(ejtag_info, addr, count, (uint32_t*)buf);
+       struct pracc_queue_info ctx = {.ejtag_info = ejtag_info};
+       pracc_queue_init(&ctx);
+
+       /** Find cache line size in bytes */
+       uint32_t clsiz;
+       if (rel) {      /* Release 2 (rel = 1) */
+               pracc_add(&ctx, 0, MIPS32_LUI(ctx.isa, 15, PRACC_UPPER_BASE_ADDR)); /* $15 = MIPS32_PRACC_BASE_ADDR */
+
+               pracc_add(&ctx, 0, MIPS32_RDHWR(ctx.isa, 8, MIPS32_SYNCI_STEP)); /* load synci_step value to $8 */
+
+               pracc_add(&ctx, MIPS32_PRACC_PARAM_OUT,
+                               MIPS32_SW(ctx.isa, 8, PRACC_OUT_OFFSET, 15));           /* store $8 to pracc_out */
+
+               pracc_add_li32(&ctx, 8, ejtag_info->reg8, 0);                           /* restore $8 */
+
+               pracc_add(&ctx, 0, MIPS32_B(ctx.isa, NEG16((ctx.code_count + 1) << ctx.isa)));  /* jump to start */
+               pracc_add(&ctx, 0, MIPS32_MFC0(ctx.isa, 15, 31, 0));                    /* restore $15 from DeSave */
+
+               ctx.retval = mips32_pracc_queue_exec(ejtag_info, &ctx, &clsiz, 1);
+               if (ctx.retval != ERROR_OK)
+                       goto exit;
+
+       } else {                        /* Release 1 (rel = 0) */
+               uint32_t conf;
+               ctx.retval = mips32_cp0_read(ejtag_info, &conf, 16, 1);
+               if (ctx.retval != ERROR_OK)
+                       goto exit;
+
+               uint32_t dl = (conf & MIPS32_CONFIG1_DL_MASK) >> MIPS32_CONFIG1_DL_SHIFT;
+
+               /* dl encoding : dl=1 => 4 bytes, dl=2 => 8 bytes, etc... max dl=6 => 128 bytes cache line size */
+               clsiz = 0x2 << dl;
+               if (dl == 0)
+                       clsiz = 0;
        }
-       
-       return ERROR_OK;
+
+       if (clsiz == 0)
+               goto exit;  /* Nothing to do */
+
+       /* make sure clsiz is power of 2 */
+       if (!IS_PWR_OF_2(clsiz)) {
+               LOG_DEBUG("clsiz must be power of 2");
+               ctx.retval = ERROR_FAIL;
+               goto exit;
+       }
+
+       /* make sure start_addr and end_addr have the same offset inside de cache line */
+       start_addr |= clsiz - 1;
+       end_addr |= clsiz - 1;
+
+       ctx.code_count = 0;
+       ctx.store_count = 0;
+
+       int count = 0;
+       uint32_t last_upper_base_addr = UPPER16((start_addr + 0x8000));
+
+       pracc_add(&ctx, 0, MIPS32_LUI(ctx.isa, 15, last_upper_base_addr)); /* load upper memory base addr to $15 */
+
+       while (start_addr <= end_addr) {                                                /* main loop */
+               uint32_t upper_base_addr = UPPER16((start_addr + 0x8000));
+               if (last_upper_base_addr != upper_base_addr) {          /* if needed, change upper addr in $15 */
+                       pracc_add(&ctx, 0, MIPS32_LUI(ctx.isa, 15, upper_base_addr));
+                       last_upper_base_addr = upper_base_addr;
+               }
+               if (rel)                        /* synci instruction, offset($15) */
+                       pracc_add(&ctx, 0, MIPS32_SYNCI(ctx.isa, LOWER16(start_addr), 15));
+
+               else {
+                       if (cached == 3)        /* cache Hit_Writeback_D, offset($15) */
+                               pracc_add(&ctx, 0, MIPS32_CACHE(ctx.isa, MIPS32_CACHE_D_HIT_WRITEBACK,
+                                                       LOWER16(start_addr), 15));
+                       /* cache Hit_Invalidate_I, offset($15) */
+                       pracc_add(&ctx, 0, MIPS32_CACHE(ctx.isa, MIPS32_CACHE_I_HIT_INVALIDATE,
+                                                       LOWER16(start_addr), 15));
+               }
+               start_addr += clsiz;
+               count++;
+               if (count == 256 && start_addr <= end_addr) {                   /* more ?, then execute code list */
+                       pracc_add(&ctx, 0, MIPS32_B(ctx.isa, NEG16((ctx.code_count + 1) << ctx.isa)));  /* to start */
+                       pracc_add(&ctx, 0, MIPS32_NOP);                                 /* nop in delay slot */
+
+                       ctx.retval = mips32_pracc_queue_exec(ejtag_info, &ctx, NULL, 1);
+                       if (ctx.retval != ERROR_OK)
+                               goto exit;
+
+                       ctx.code_count = 0;     /* reset counters for another loop */
+                       ctx.store_count = 0;
+                       count = 0;
+               }
+       }
+       pracc_add(&ctx, 0, MIPS32_SYNC(ctx.isa));
+       pracc_add(&ctx, 0, MIPS32_B(ctx.isa, NEG16((ctx.code_count + 1) << ctx.isa)));          /* jump to start */
+       pracc_add(&ctx, 0, MIPS32_MFC0(ctx.isa, 15, 31, 0));                            /* restore $15 from DeSave*/
+
+       ctx.retval = mips32_pracc_queue_exec(ejtag_info, &ctx, NULL, 1);
+exit:
+       pracc_queue_free(&ctx);
+       return ctx.retval;
 }
 
-int mips32_pracc_write_mem32(mips_ejtag_t *ejtag_info, uint32_t addr, int count, uint32_t *buf)
+static int mips32_pracc_write_mem_generic(struct mips_ejtag *ejtag_info,
+               uint32_t addr, int size, int count, const void *buf)
 {
+       struct pracc_queue_info ctx = {.ejtag_info = ejtag_info};
+       pracc_queue_init(&ctx);
+
+       const uint32_t *buf32 = buf;
+       const uint16_t *buf16 = buf;
+       const uint8_t *buf8 = buf;
+
+       while (count) {
+               ctx.code_count = 0;
+               ctx.store_count = 0;
+
+               int this_round_count = (count > 128) ? 128 : count;
+               uint32_t last_upper_base_addr = UPPER16((addr + 0x8000));
+                             /* load $15 with memory base address */
+               pracc_add(&ctx, 0, MIPS32_LUI(ctx.isa, 15, last_upper_base_addr));
+
+               for (int i = 0; i != this_round_count; i++) {
+                       uint32_t upper_base_addr = UPPER16((addr + 0x8000));
+                       if (last_upper_base_addr != upper_base_addr) {  /* if needed, change upper address in $15*/
+                               pracc_add(&ctx, 0, MIPS32_LUI(ctx.isa, 15, upper_base_addr));
+                               last_upper_base_addr = upper_base_addr;
+                       }
 
-//NC: use destination pointer as loop counter (last address is in $10)
-       uint32_t code[] = {
-                                                                                                                       /* start: */
-               MIPS32_MTC0(15,31,0),                                                           /* move $15 to COP0 DeSave */
-               MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)),             /* $15 = MIPS32_PRACC_STACK */
-               MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
-               MIPS32_SW(8,0,15),                                                                      /* sw $8,($15) */
-               MIPS32_SW(9,0,15),                                                                      /* sw $9,($15) */
-               MIPS32_SW(10,0,15),                                                             /* sw $10,($15) */
-               MIPS32_SW(11,0,15),                                                             /* sw $11,($15) */
-               
-               MIPS32_ADDI(8,15,NEG16(MIPS32_PRACC_STACK-MIPS32_PRACC_PARAM_IN)),  //$8= MIPS32_PRACC_PARAM_IN
-               MIPS32_LW(9,0,8),                                                                       /* Load write addr to $9 */
-               MIPS32_LW(10,4,8),      //last address                                                                  /* Load write count to $10 */
-               MIPS32_ADDI(8,8,8),     // $8 += 8 beginning of data
-
-//loop:
-               MIPS32_LW(11,0,8),                                                                      /* lw $11,0($8), Load $11 with the word @mem[$8] */
-               MIPS32_SW(11,0,9),                                                                      /* sw $11,0($9) */
-               
-               MIPS32_ADDI(9,9,4),                                                             /* $9 += 4 */
-               MIPS32_BNE(10,9,NEG16(4)),  //was 9 BNE $10, 9, loop                                                                    /* b loop */
-               MIPS32_ADDI(8,8,4),  //this instruction is part of the loop (one delay slot)!   /* $8 += 4 */
-                                                                                                                       /* end: */
-               MIPS32_LW(11,0,15),                                                             /* lw $11,($15) */
-               MIPS32_LW(10,0,15),                                                             /* lw $10,($15) */
-               MIPS32_LW(9,0,15),                                                                      /* lw $9,($15) */
-               MIPS32_LW(8,0,15),                                                                      /* lw $8,($15) */
-               MIPS32_B(NEG16(21)),     //was 30                                                       /* b start */
-               MIPS32_MFC0(15,31,0),                                                           /* move COP0 DeSave to $15 */
-               MIPS32_NOP, //this one will not be executed
-       };
-       
-       /* TODO remove array */
-       uint32_t param_in[count+2];
-       param_in[0] = addr;
-       param_in[1] = addr + count * sizeof(uint32_t);  //last address
-    
-       memcpy(&param_in[2], buf, count * sizeof(uint32_t));
-       
-       mips32_pracc_exec(ejtag_info, sizeof(code)/sizeof(code[0]), code, \
-               sizeof(param_in)/sizeof(param_in[0]),param_in, 0, NULL, 1);
+                       if (size == 4) {
+                               pracc_add_li32(&ctx, 8, *buf32, 1);             /* load with li32, optimize */
+                               pracc_add(&ctx, 0, MIPS32_SW(ctx.isa, 8, LOWER16(addr), 15)); /* store word to mem */
+                               buf32++;
 
-       return ERROR_OK;
+                       } else if (size == 2) {
+                               pracc_add(&ctx, 0, MIPS32_ORI(ctx.isa, 8, 0, *buf16));          /* load lower value */
+                               pracc_add(&ctx, 0, MIPS32_SH(ctx.isa, 8, LOWER16(addr), 15)); /* store half word */
+                               buf16++;
+
+                       } else {
+                               pracc_add(&ctx, 0, MIPS32_ORI(ctx.isa, 8, 0, *buf8));           /* load lower value */
+                               pracc_add(&ctx, 0, MIPS32_SB(ctx.isa, 8, LOWER16(addr), 15));   /* store byte */
+                               buf8++;
+                       }
+                       addr += size;
+               }
+
+               pracc_add_li32(&ctx, 8, ejtag_info->reg8, 0);                           /* restore $8 */
+
+               pracc_add(&ctx, 0, MIPS32_B(ctx.isa, NEG16((ctx.code_count + 1) << ctx.isa)));  /* jump to start */
+               pracc_add(&ctx, 0, MIPS32_MFC0(ctx.isa, 15, 31, 0));                    /* restore $15 from DeSave */
+
+               ctx.retval = mips32_pracc_queue_exec(ejtag_info, &ctx, NULL, 1);
+               if (ctx.retval != ERROR_OK)
+                       goto exit;
+               count -= this_round_count;
+       }
+exit:
+       pracc_queue_free(&ctx);
+       return ctx.retval;
 }
 
-int mips32_pracc_write_u32(mips_ejtag_t *ejtag_info, uint32_t addr, uint32_t *buf)
+int mips32_pracc_write_mem(struct mips_ejtag *ejtag_info, uint32_t addr, int size, int count, const void *buf)
 {
-       uint32_t code[] = {
-                                                                                                                       /* start: */
-               MIPS32_MTC0(15,31,0),                                                           /* move $15 to COP0 DeSave */
-               MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)),             /* $15 = MIPS32_PRACC_STACK */
-               MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
-               MIPS32_SW(8,0,15),                                                                      /* sw $8,($15) */
-               MIPS32_SW(9,0,15),                                                                      /* sw $9,($15) */
-       
-               MIPS32_LW(8,NEG16((MIPS32_PRACC_STACK-MIPS32_PRACC_PARAM_IN)-4), 15),  //load R8 @ param_in[1] = data
-               MIPS32_LW(9,NEG16(MIPS32_PRACC_STACK-MIPS32_PRACC_PARAM_IN), 15),  //load R9 @ param_in[0] = address
-
-               MIPS32_SW(8,0,9),                                                                       /* sw $8,0($9) */
-
-               MIPS32_LW(9,0,15),                                                                      /* lw $9,($15) */
-               MIPS32_LW(8,0,15),                                                                      /* lw $8,($15) */
-               MIPS32_B(NEG16(11)),                                                            /* b start */
-               MIPS32_MFC0(15,31,0),                                                   /* move COP0 DeSave to $15 */
-               MIPS32_NOP,
-       };
+       int retval = mips32_pracc_write_mem_generic(ejtag_info, addr, size, count, buf);
+       if (retval != ERROR_OK)
+               return retval;
 
-       /* TODO remove array */
-       uint32_t param_in[1+1];
-       param_in[0] = addr;
-       param_in[1] = *buf;
+       /**
+        * If we are in the cacheable region and cache is activated,
+        * we must clean D$ (if Cache Coherency Attribute is set to 3) + invalidate I$ after we did the write,
+        * so that changes do not continue to live only in D$ (if CCA = 3), but to be
+        * replicated in I$ also (maybe we wrote the instructions)
+        */
+       uint32_t conf = 0;
+       int cached = 0;
 
-       mips32_pracc_exec(ejtag_info, sizeof(code)/sizeof(code[0]), code, \
-               sizeof(param_in)/sizeof(param_in[0]),param_in, 0, NULL, 1);
+       if ((KSEGX(addr) == KSEG1) || ((addr >= 0xff200000) && (addr <= 0xff3fffff)))
+               return retval; /*Nothing to do*/
 
-       return ERROR_OK;
+       mips32_cp0_read(ejtag_info, &conf, 16, 0);
+
+       switch (KSEGX(addr)) {
+               case KUSEG:
+                       cached = (conf & MIPS32_CONFIG0_KU_MASK) >> MIPS32_CONFIG0_KU_SHIFT;
+                       break;
+               case KSEG0:
+                       cached = (conf & MIPS32_CONFIG0_K0_MASK) >> MIPS32_CONFIG0_K0_SHIFT;
+                       break;
+               case KSEG2:
+               case KSEG3:
+                       cached = (conf & MIPS32_CONFIG0_K23_MASK) >> MIPS32_CONFIG0_K23_SHIFT;
+                       break;
+               default:
+                       /* what ? */
+                       break;
+       }
+
+       /**
+        * Check cacheability bits coherency algorithm
+        * is the region cacheable or uncached.
+        * If cacheable we have to synchronize the cache
+        */
+       if (cached == 3 || cached == 0) {               /* Write back cache or write through cache */
+               uint32_t start_addr = addr;
+               uint32_t end_addr = addr + count * size;
+               uint32_t rel = (conf & MIPS32_CONFIG0_AR_MASK) >> MIPS32_CONFIG0_AR_SHIFT;
+               if (rel > 1) {
+                       LOG_DEBUG("Unknown release in cache code");
+                       return ERROR_FAIL;
+               }
+               retval = mips32_pracc_synchronize_cache(ejtag_info, start_addr, end_addr, cached, rel);
+       }
+
+       return retval;
 }
 
-int mips32_pracc_write_mem16(mips_ejtag_t *ejtag_info, uint32_t addr, int count, uint16_t *buf)
+int mips32_pracc_write_regs(struct mips_ejtag *ejtag_info, uint32_t *regs)
 {
-       uint32_t code[] = {
-                                                                                                                       /* start: */
-               MIPS32_MTC0(15,31,0),                                                           /* move $15 to COP0 DeSave */
-               MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)),             /* $15 = MIPS32_PRACC_STACK */
-               MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
-               MIPS32_SW(8,0,15),                                                                      /* sw $8,($15) */
-               MIPS32_SW(9,0,15),                                                                      /* sw $9,($15) */
-               MIPS32_SW(10,0,15),                                                             /* sw $10,($15) */
-               MIPS32_SW(11,0,15),                                                             /* sw $11,($15) */
-               
-               MIPS32_LUI(8,UPPER16(MIPS32_PRACC_PARAM_IN)),           /* $8 = MIPS32_PRACC_PARAM_IN */
-               MIPS32_ORI(8,8,LOWER16(MIPS32_PRACC_PARAM_IN)),
-               MIPS32_LW(9,0,8),                                                                       /* Load write addr to $9 */
-               MIPS32_LW(10,4,8),                                                                      /* Load write count to $10 */
-               MIPS32_ADDI(8,8,8),                                                             /* $8 += 8 */
-               MIPS32_NOP,
-                                                                                                                       /* loop: */
-               MIPS32_BEQ(0,10,9),                                                                     /* beq $0, $10, end */
-               MIPS32_NOP,
-               
-               MIPS32_LW(11,0,8),                                                                      /* lw $11,0($8), Load $11 with the word @mem[$8] */
-               MIPS32_SH(11,0,9),                                                                      /* sh $11,0($9) */
-               
-               MIPS32_ADDI(10,10,NEG16(1)),                                            /* $10-- */
-               MIPS32_ADDI(9,9,2),                                                             /* $9 += 2 */
-               MIPS32_ADDI(8,8,4),                                                             /* $8 += 4 */
-               
-               MIPS32_NOP,
-               MIPS32_B(NEG16(9)),                                                                     /* b loop */
-               MIPS32_NOP,
-                                                                                                                       /* end: */
-               MIPS32_LW(11,0,15),                                                             /* lw $11,($15) */
-               MIPS32_LW(10,0,15),                                                             /* lw $10,($15) */
-               MIPS32_LW(9,0,15),                                                                      /* lw $9,($15) */
-               MIPS32_LW(8,0,15),                                                                      /* lw $8,($15) */
-               MIPS32_MFC0(15,31,0),                                                           /* move COP0 DeSave to $15 */
-               MIPS32_NOP,
-               MIPS32_B(NEG16(30)),                                                            /* b start */
-               MIPS32_NOP,
+       struct pracc_queue_info ctx = {.ejtag_info = ejtag_info};
+       pracc_queue_init(&ctx);
+
+       uint32_t cp0_write_code[] = {
+               MIPS32_MTC0(ctx.isa, 1, 12, 0),                                 /* move $1 to status */
+               MIPS32_MTLO(ctx.isa, 1),                                                /* move $1 to lo */
+               MIPS32_MTHI(ctx.isa, 1),                                                /* move $1 to hi */
+               MIPS32_MTC0(ctx.isa, 1, 8, 0),                                  /* move $1 to badvaddr */
+               MIPS32_MTC0(ctx.isa, 1, 13, 0),                                 /* move $1 to cause*/
+               MIPS32_MTC0(ctx.isa, 1, 24, 0),                                 /* move $1 to depc (pc) */
        };
-       
-       /* TODO remove array */
-       uint32_t param_in[count+2];
-       int i;
-       param_in[0] = addr;
-       param_in[1] = count;
-       
-       for (i = 0; i < count; i++)
-       {
-               param_in[i+2] = buf[i];
+
+       /* load registers 2 to 31 with li32, optimize */
+       for (int i = 2; i < 32; i++)
+               pracc_add_li32(&ctx, i, regs[i], 1);
+
+       for (int i = 0; i != 6; i++) {
+               pracc_add_li32(&ctx, 1, regs[i + 32], 0);       /* load CPO value in $1 */
+               pracc_add(&ctx, 0, cp0_write_code[i]);                  /* write value from $1 to CPO register */
        }
-       
-       mips32_pracc_exec(ejtag_info, sizeof(code)/sizeof(code[0]), code, \
-               sizeof(param_in)/sizeof(param_in[0]), param_in, 0, NULL, 1);
+       pracc_add(&ctx, 0, MIPS32_MTC0(ctx.isa, 15, 31, 0));                            /* load $15 in DeSave */
+       pracc_add(&ctx, 0, MIPS32_LUI(ctx.isa, 1, UPPER16((regs[1]))));         /* load upper half word in $1 */
+       pracc_add(&ctx, 0, MIPS32_B(ctx.isa, NEG16((ctx.code_count + 1) << ctx.isa)));          /* jump to start */
+       pracc_add(&ctx, 0, MIPS32_ORI(ctx.isa, 1, 1, LOWER16((regs[1]))));      /* load lower half word in $1 */
 
-       return ERROR_OK;
+       ctx.retval = mips32_pracc_queue_exec(ejtag_info, &ctx, NULL, 1);
+
+       ejtag_info->reg8 = regs[8];
+       ejtag_info->reg9 = regs[9];
+       pracc_queue_free(&ctx);
+       return ctx.retval;
 }
 
-int mips32_pracc_write_mem8(mips_ejtag_t *ejtag_info, uint32_t addr, int count, uint8_t *buf)
+int mips32_pracc_read_regs(struct mips_ejtag *ejtag_info, uint32_t *regs)
 {
-       uint32_t code[] = {
-                                                                                                                       /* start: */
-               MIPS32_MTC0(15,31,0),                                                           /* move $15 to COP0 DeSave */
-               MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)),             /* $15 = MIPS32_PRACC_STACK */
-               MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
-               MIPS32_SW(8,0,15),                                                                      /* sw $8,($15) */
-               MIPS32_SW(9,0,15),                                                                      /* sw $9,($15) */
-               MIPS32_SW(10,0,15),                                                             /* sw $10,($15) */
-               MIPS32_SW(11,0,15),                                                             /* sw $11,($15) */
-               
-               MIPS32_LUI(8,UPPER16(MIPS32_PRACC_PARAM_IN)),           /* $8 = MIPS32_PRACC_PARAM_IN */
-               MIPS32_ORI(8,8,LOWER16(MIPS32_PRACC_PARAM_IN)),
-               MIPS32_LW(9,0,8),                                                                       /* Load write addr to $9 */
-               MIPS32_LW(10,4,8),                                                                      /* Load write count to $10 */
-               MIPS32_ADDI(8,8,8),                                                             /* $8 += 8 */
-               MIPS32_NOP,
-                                                                                                                       /* loop: */
-               MIPS32_BEQ(0,10,9),                                                                     /* beq $0, $10, end */
-               MIPS32_NOP,
-               
-               MIPS32_LW(11,0,8),                                                                      /* lw $11,0($8), Load $11 with the word @mem[$8] */
-               MIPS32_SB(11,0,9),                                                                      /* sb $11,0($9) */
-               
-               MIPS32_ADDI(10,10,NEG16(1)),                                            /* $10-- */
-               MIPS32_ADDI(9,9,1),                                                             /* $9 += 1 */
-               MIPS32_ADDI(8,8,4),                                                             /* $8 += 4 */
-               
-               MIPS32_NOP,
-               MIPS32_B(NEG16(9)),                                                                     /* b loop */
-               MIPS32_NOP,
-                                                                                                                       /* end: */
-               MIPS32_LW(11,0,15),                                                             /* lw $11,($15) */
-               MIPS32_LW(10,0,15),                                                             /* lw $10,($15) */
-               MIPS32_LW(9,0,15),                                                                      /* lw $9,($15) */
-               MIPS32_LW(8,0,15),                                                                      /* lw $8,($15) */
-               MIPS32_MFC0(15,31,0),                                                           /* move COP0 DeSave to $15 */
-               MIPS32_NOP,
-               MIPS32_B(NEG16(30)),                                                            /* b start */
-               MIPS32_NOP,
+       struct pracc_queue_info ctx = {.ejtag_info = ejtag_info};
+       pracc_queue_init(&ctx);
+
+       uint32_t cp0_read_code[] = {
+               MIPS32_MFC0(ctx.isa, 8, 12, 0),                                 /* move status to $8 */
+               MIPS32_MFLO(ctx.isa, 8),                                                /* move lo to $8 */
+               MIPS32_MFHI(ctx.isa, 8),                                                /* move hi to $8 */
+               MIPS32_MFC0(ctx.isa, 8, 8, 0),                                  /* move badvaddr to $8 */
+               MIPS32_MFC0(ctx.isa, 8, 13, 0),                                 /* move cause to $8 */
+               MIPS32_MFC0(ctx.isa, 8, 24, 0),                                 /* move depc (pc) to $8 */
        };
-       
-       /* TODO remove array */
-       uint32_t param_in[count+2];
-       int retval;
-       int i;
-       param_in[0] = addr;
-       param_in[1] = count;
-       
-       for (i = 0; i < count; i++)
-       {
-               param_in[i+2] = buf[i];
+
+       pracc_add(&ctx, 0, MIPS32_MTC0(ctx.isa, 1, 31, 0));                             /* move $1 to COP0 DeSave */
+       pracc_add(&ctx, 0, MIPS32_LUI(ctx.isa, 1, PRACC_UPPER_BASE_ADDR));      /* $1 = MIP32_PRACC_BASE_ADDR */
+
+       for (int i = 2; i != 32; i++)                                   /* store GPR's 2 to 31 */
+               pracc_add(&ctx, MIPS32_PRACC_PARAM_OUT + (i * 4),
+                                 MIPS32_SW(ctx.isa, i, PRACC_OUT_OFFSET + (i * 4), 1));
+
+       for (int i = 0; i != 6; i++) {
+               pracc_add(&ctx, 0, cp0_read_code[i]);                           /* load COP0 needed registers to $8 */
+               pracc_add(&ctx, MIPS32_PRACC_PARAM_OUT + (i + 32) * 4,                  /* store $8 at PARAM OUT */
+                                 MIPS32_SW(ctx.isa, 8, PRACC_OUT_OFFSET + (i + 32) * 4, 1));
        }
-       
-       retval = mips32_pracc_exec(ejtag_info, sizeof(code)/sizeof(code[0]), code, \
-               sizeof(param_in)/sizeof(param_in[0]), param_in, 0, NULL, 1);
+       pracc_add(&ctx, 0, MIPS32_MFC0(ctx.isa, 8, 31, 0));                     /* move DeSave to $8, reg1 value */
+       pracc_add(&ctx, MIPS32_PRACC_PARAM_OUT + 4,                     /* store reg1 value from $8 to param out */
+                         MIPS32_SW(ctx.isa, 8, PRACC_OUT_OFFSET + 4, 1));
 
-       return retval;
+       pracc_add(&ctx, 0, MIPS32_MFC0(ctx.isa, 1, 31, 0));             /* move COP0 DeSave to $1, restore reg1 */
+       pracc_add(&ctx, 0, MIPS32_B(ctx.isa, NEG16((ctx.code_count + 1) << ctx.isa)));          /* jump to start */
+       pracc_add(&ctx, 0, MIPS32_MTC0(ctx.isa, 15, 31, 0));                            /* load $15 in DeSave */
+
+       ctx.retval = mips32_pracc_queue_exec(ejtag_info, &ctx, regs, 1);
+
+       ejtag_info->reg8 = regs[8];     /* reg8 is saved but not restored, next called function should restore it */
+       ejtag_info->reg9 = regs[9];
+       pracc_queue_free(&ctx);
+       return ctx.retval;
 }
 
-int mips32_pracc_write_regs(mips_ejtag_t *ejtag_info, uint32_t *regs)
+/* fastdata upload/download requires an initialized working area
+ * to load the download code; it should not be called otherwise
+ * fetch order from the fastdata area
+ * 1. start addr
+ * 2. end addr
+ * 3. data ...
+ */
+int mips32_pracc_fastdata_xfer(struct mips_ejtag *ejtag_info, struct working_area *source,
+               int write_t, uint32_t addr, int count, uint32_t *buf)
 {
-       uint32_t code[] = {
-                                                                                                               /* start: */
-               MIPS32_LUI(2,UPPER16(MIPS32_PRACC_PARAM_IN)),   /* $2 = MIPS32_PRACC_PARAM_IN */
-               MIPS32_ORI(2,2,LOWER16(MIPS32_PRACC_PARAM_IN)),
-               MIPS32_LW(1,1*4,2),                                                     /* lw $1,1*4($2) */
-               MIPS32_LW(15,15*4,2),                                                   /* lw $15,15*4($2) */
-               MIPS32_MTC0(15,31,0),                                                   /* move $15 to COP0 DeSave */
-               MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)),     /* $15 = MIPS32_PRACC_STACK */
-               MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
-               MIPS32_SW(1,0,15),                                                              /* sw $1,($15) */
-               MIPS32_LUI(1,UPPER16(MIPS32_PRACC_PARAM_IN)),   /* $1 = MIPS32_PRACC_PARAM_IN */
-               MIPS32_ORI(1,1,LOWER16(MIPS32_PRACC_PARAM_IN)),
-               MIPS32_LW(3,3*4,1),                                                     /* lw $3,3*4($1) */
-               MIPS32_LW(4,4*4,1),                                                     /* lw $4,4*4($1) */
-               MIPS32_LW(5,5*4,1),                                                     /* lw $5,5*4($1) */
-               MIPS32_LW(6,6*4,1),                                                     /* lw $6,6*4($1) */
-               MIPS32_LW(7,7*4,1),                                                     /* lw $7,7*4($1) */
-               MIPS32_LW(8,8*4,1),                                                     /* lw $8,8*4($1) */
-               MIPS32_LW(9,9*4,1),                                                     /* lw $9,9*4($1) */
-               MIPS32_LW(10,10*4,1),                                                   /* lw $10,10*4($1) */
-               MIPS32_LW(11,11*4,1),                                                   /* lw $11,11*4($1) */
-               MIPS32_LW(12,12*4,1),                                                   /* lw $12,12*4($1) */
-               MIPS32_LW(13,13*4,1),                                                   /* lw $13,13*4($1) */
-               MIPS32_LW(14,14*4,1),                                                   /* lw $14,14*4($1) */
-               MIPS32_LW(16,16*4,1),                                                   /* lw $16,16*4($1) */
-               MIPS32_LW(17,17*4,1),                                                   /* lw $17,17*4($1) */
-               MIPS32_LW(18,18*4,1),                                                   /* lw $18,18*4($1) */
-               MIPS32_LW(19,19*4,1),                                                   /* lw $19,19*4($1) */
-               MIPS32_LW(20,20*4,1),                                                   /* lw $20,20*4($1) */
-               MIPS32_LW(21,21*4,1),                                                   /* lw $21,21*4($1) */
-               MIPS32_LW(22,22*4,1),                                                   /* lw $22,22*4($1) */
-               MIPS32_LW(23,23*4,1),                                                   /* lw $23,23*4($1) */
-               MIPS32_LW(24,24*4,1),                                                   /* lw $24,24*4($1) */
-               MIPS32_LW(25,25*4,1),                                                   /* lw $25,25*4($1) */
-               MIPS32_LW(26,26*4,1),                                                   /* lw $26,26*4($1) */
-               MIPS32_LW(27,27*4,1),                                                   /* lw $27,27*4($1) */
-               MIPS32_LW(28,28*4,1),                                                   /* lw $28,28*4($1) */
-               MIPS32_LW(29,29*4,1),                                                   /* lw $29,29*4($1) */
-               MIPS32_LW(30,30*4,1),                                                   /* lw $30,30*4($1) */
-               MIPS32_LW(31,31*4,1),                                                   /* lw $31,31*4($1) */
-               
-               MIPS32_LW(2,32*4,1),                                                    /* lw $2,32*4($1) */
-               MIPS32_MTC0(2,12,0),                                                    /* move $2 to status */
-               MIPS32_LW(2,33*4,1),                                                    /* lw $2,33*4($1) */
-               MIPS32_MTLO(2),                                                                 /* move $2 to lo */
-               MIPS32_LW(2,34*4,1),                                                    /* lw $2,34*4($1) */
-               MIPS32_MTHI(2),                                                                 /* move $2 to hi */
-               MIPS32_LW(2,35*4,1),                                                    /* lw $2,35*4($1) */
-               MIPS32_MTC0(2,8,0),                                                             /* move $2 to badvaddr */
-               MIPS32_LW(2,36*4,1),                                                    /* lw $2,36*4($1) */
-               MIPS32_MTC0(2,13,0),                                                    /* move $2 to cause*/
-               MIPS32_LW(2,37*4,1),                                                    /* lw $2,37*4($1) */
-               MIPS32_MTC0(2,24,0),                                                    /* move $2 to pc */
-               
-               MIPS32_LW(2,2*4,1),                                                     /* lw $2,2*4($1) */
-               MIPS32_LW(1,0,15),                                                              /* lw $1,($15) */
-               MIPS32_MFC0(15,31,0),                                                   /* move COP0 DeSave to $15 */
-               MIPS32_NOP,
-               MIPS32_B(NEG16(55)),                                                    /* b start */
-               MIPS32_NOP,
+       uint32_t isa = ejtag_info->isa ? 1 : 0;
+       uint32_t handler_code[] = {
+               /* r15 points to the start of this code */
+               MIPS32_SW(isa, 8, MIPS32_FASTDATA_HANDLER_SIZE - 4, 15),
+               MIPS32_SW(isa, 9, MIPS32_FASTDATA_HANDLER_SIZE - 8, 15),
+               MIPS32_SW(isa, 10, MIPS32_FASTDATA_HANDLER_SIZE - 12, 15),
+               MIPS32_SW(isa, 11, MIPS32_FASTDATA_HANDLER_SIZE - 16, 15),
+               /* start of fastdata area in t0 */
+               MIPS32_LUI(isa, 8, UPPER16(MIPS32_PRACC_FASTDATA_AREA)),
+               MIPS32_ORI(isa, 8, 8, LOWER16(MIPS32_PRACC_FASTDATA_AREA)),
+               MIPS32_LW(isa, 9, 0, 8),                                                /* start addr in t1 */
+               MIPS32_LW(isa, 10, 0, 8),                                               /* end addr to t2 */
+                                       /* loop: */
+               write_t ? MIPS32_LW(isa, 11, 0, 8) : MIPS32_LW(isa, 11, 0, 9),  /* from xfer area : from memory */
+               write_t ? MIPS32_SW(isa, 11, 0, 9) : MIPS32_SW(isa, 11, 0, 8),  /* to memory      : to xfer area */
+
+               MIPS32_BNE(isa, 10, 9, NEG16(3 << isa)),                        /* bne $t2,t1,loop */
+               MIPS32_ADDI(isa, 9, 9, 4),                                      /* addi t1,t1,4 */
+
+               MIPS32_LW(isa, 8, MIPS32_FASTDATA_HANDLER_SIZE - 4, 15),
+               MIPS32_LW(isa, 9, MIPS32_FASTDATA_HANDLER_SIZE - 8, 15),
+               MIPS32_LW(isa, 10, MIPS32_FASTDATA_HANDLER_SIZE - 12, 15),
+               MIPS32_LW(isa, 11, MIPS32_FASTDATA_HANDLER_SIZE - 16, 15),
+
+               MIPS32_LUI(isa, 15, UPPER16(MIPS32_PRACC_TEXT)),
+               MIPS32_ORI(isa, 15, 15, LOWER16(MIPS32_PRACC_TEXT) | isa),      /* isa bit for JR instr */
+               MIPS32_JR(isa, 15),                                                             /* jr start */
+               MIPS32_MFC0(isa, 15, 31, 0),                                    /* move COP0 DeSave to $15 */
        };
-       
-       int retval;
-       
-       retval = mips32_pracc_exec(ejtag_info, sizeof(code)/sizeof(code[0]), code, \
-               38, regs, 0, NULL, 1);
-       
-       return retval;
-}
 
-int mips32_pracc_read_regs(mips_ejtag_t *ejtag_info, uint32_t *regs)
-{
-       uint32_t code[] = {
-                                                                                                               /* start: */
-               MIPS32_MTC0(2,31,0),                                                    /* move $2 to COP0 DeSave */
-               MIPS32_LUI(2,UPPER16(MIPS32_PRACC_PARAM_OUT)),  /* $2 = MIPS32_PRACC_PARAM_OUT */
-               MIPS32_ORI(2,2,LOWER16(MIPS32_PRACC_PARAM_OUT)),
-               MIPS32_SW(0,0*4,2),                                                             /* sw $0,0*4($2) */
-               MIPS32_SW(1,1*4,2),                                                     /* sw $1,1*4($2) */
-               MIPS32_SW(15,15*4,2),                                                   /* sw $15,15*4($2) */
-               MIPS32_MFC0(2,31,0),                                                    /* move COP0 DeSave to $2 */
-               MIPS32_MTC0(15,31,0),                                                   /* move $15 to COP0 DeSave */
-               MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)),     /* $15 = MIPS32_PRACC_STACK */
-               MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
-               MIPS32_SW(1,0,15),                                                              /* sw $1,($15) */
-               MIPS32_SW(2,0,15),                                                              /* sw $2,($15) */
-               MIPS32_LUI(1,UPPER16(MIPS32_PRACC_PARAM_OUT)),  /* $1 = MIPS32_PRACC_PARAM_OUT */
-               MIPS32_ORI(1,1,LOWER16(MIPS32_PRACC_PARAM_OUT)),
-               MIPS32_SW(2,2*4,1),                                                     /* sw $2,2*4($1) */
-               MIPS32_SW(3,3*4,1),                                                     /* sw $3,3*4($1) */
-               MIPS32_SW(4,4*4,1),                                                     /* sw $4,4*4($1) */
-               MIPS32_SW(5,5*4,1),                                                     /* sw $5,5*4($1) */
-               MIPS32_SW(6,6*4,1),                                                     /* sw $6,6*4($1) */
-               MIPS32_SW(7,7*4,1),                                                     /* sw $7,7*4($1) */
-               MIPS32_SW(8,8*4,1),                                                     /* sw $8,8*4($1) */
-               MIPS32_SW(9,9*4,1),                                                     /* sw $9,9*4($1) */
-               MIPS32_SW(10,10*4,1),                                                   /* sw $10,10*4($1) */
-               MIPS32_SW(11,11*4,1),                                                   /* sw $11,11*4($1) */
-               MIPS32_SW(12,12*4,1),                                                   /* sw $12,12*4($1) */
-               MIPS32_SW(13,13*4,1),                                                   /* sw $13,13*4($1) */
-               MIPS32_SW(14,14*4,1),                                                   /* sw $14,14*4($1) */
-               MIPS32_SW(16,16*4,1),                                                   /* sw $16,16*4($1) */
-               MIPS32_SW(17,17*4,1),                                                   /* sw $17,17*4($1) */
-               MIPS32_SW(18,18*4,1),                                                   /* sw $18,18*4($1) */
-               MIPS32_SW(19,19*4,1),                                                   /* sw $19,19*4($1) */
-               MIPS32_SW(20,20*4,1),                                                   /* sw $20,20*4($1) */
-               MIPS32_SW(21,21*4,1),                                                   /* sw $21,21*4($1) */
-               MIPS32_SW(22,22*4,1),                                                   /* sw $22,22*4($1) */
-               MIPS32_SW(23,23*4,1),                                                   /* sw $23,23*4($1) */
-               MIPS32_SW(24,24*4,1),                                                   /* sw $24,24*4($1) */
-               MIPS32_SW(25,25*4,1),                                                   /* sw $25,25*4($1) */
-               MIPS32_SW(26,26*4,1),                                                   /* sw $26,26*4($1) */
-               MIPS32_SW(27,27*4,1),                                                   /* sw $27,27*4($1) */
-               MIPS32_SW(28,28*4,1),                                                   /* sw $28,28*4($1) */
-               MIPS32_SW(29,29*4,1),                                                   /* sw $29,29*4($1) */
-               MIPS32_SW(30,30*4,1),                                                   /* sw $30,30*4($1) */
-               MIPS32_SW(31,31*4,1),                                                   /* sw $31,31*4($1) */
-               
-               MIPS32_MFC0(2,12,0),                                                    /* move status to $2 */
-               MIPS32_SW(2,32*4,1),                                                    /* sw $2,32*4($1) */
-               MIPS32_MFLO(2),                                                                 /* move lo to $2 */
-               MIPS32_SW(2,33*4,1),                                                    /* sw $2,33*4($1) */
-               MIPS32_MFHI(2),                                                                 /* move hi to $2 */
-               MIPS32_SW(2,34*4,1),                                                    /* sw $2,34*4($1) */
-               MIPS32_MFC0(2,8,0),                                                             /* move badvaddr to $2 */
-               MIPS32_SW(2,35*4,1),                                                    /* sw $2,35*4($1) */
-               MIPS32_MFC0(2,13,0),                                                    /* move cause to $2 */
-               MIPS32_SW(2,36*4,1),                                                    /* sw $2,36*4($1) */
-               MIPS32_MFC0(2,24,0),                                                    /* move pc to $2 */
-               MIPS32_SW(2,37*4,1),                                                    /* sw $2,37*4($1) */
-               
-               MIPS32_LW(2,0,15),                                                              /* lw $2,($15) */
-               MIPS32_LW(1,0,15),                                                              /* lw $1,($15) */
-               MIPS32_MFC0(15,31,0),                                                   /* move COP0 DeSave to $15 */
-               MIPS32_NOP,
-               MIPS32_B(NEG16(60)),                                                    /* b start */
-               MIPS32_NOP,
+       if (source->size < MIPS32_FASTDATA_HANDLER_SIZE)
+               return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
+
+       pracc_swap16_array(ejtag_info, handler_code, ARRAY_SIZE(handler_code));
+               /* write program into RAM */
+       if (write_t != ejtag_info->fast_access_save) {
+               mips32_pracc_write_mem(ejtag_info, source->address, 4, ARRAY_SIZE(handler_code), handler_code);
+               /* save previous operation to speed to any consecutive read/writes */
+               ejtag_info->fast_access_save = write_t;
+       }
+
+       LOG_DEBUG("%s using 0x%.8" TARGET_PRIxADDR " for write handler", __func__, source->address);
+
+       uint32_t jmp_code[] = {
+               MIPS32_LUI(isa, 15, UPPER16(source->address)),                  /* load addr of jump in $15 */
+               MIPS32_ORI(isa, 15, 15, LOWER16(source->address) | isa),        /* isa bit for JR instr */
+               MIPS32_JR(isa, 15),                                             /* jump to ram program */
+               isa ? MIPS32_XORI(isa, 15, 15, 1) : MIPS32_NOP, /* drop isa bit, needed for LW/SW instructions */
        };
-       
-       int retval;
-       
-       retval = mips32_pracc_exec(ejtag_info, sizeof(code)/sizeof(code[0]), code, \
-               0, NULL, 38, regs, 1);
-       
+
+       pracc_swap16_array(ejtag_info, jmp_code, ARRAY_SIZE(jmp_code));
+
+       /* execute jump code, with no address check */
+       for (unsigned i = 0; i < ARRAY_SIZE(jmp_code); i++) {
+               int retval = wait_for_pracc_rw(ejtag_info);
+               if (retval != ERROR_OK)
+                       return retval;
+
+               mips_ejtag_set_instr(ejtag_info, EJTAG_INST_DATA);
+               mips_ejtag_drscan_32_out(ejtag_info, jmp_code[i]);
+
+               /* Clear the access pending bit (let the processor eat!) */
+               mips32_pracc_finish(ejtag_info);
+       }
+
+       /* wait PrAcc pending bit for FASTDATA write, read address */
+       int retval = mips32_pracc_read_ctrl_addr(ejtag_info);
+       if (retval != ERROR_OK)
+               return retval;
+
+       /* next fetch to dmseg should be in FASTDATA_AREA, check */
+       if (ejtag_info->pa_addr != MIPS32_PRACC_FASTDATA_AREA)
+               return ERROR_FAIL;
+
+       /* Send the load start address */
+       uint32_t val = addr;
+       mips_ejtag_set_instr(ejtag_info, EJTAG_INST_FASTDATA);
+       mips_ejtag_fastdata_scan(ejtag_info, 1, &val);
+
+       retval = wait_for_pracc_rw(ejtag_info);
+       if (retval != ERROR_OK)
+               return retval;
+
+       /* Send the load end address */
+       val = addr + (count - 1) * 4;
+       mips_ejtag_set_instr(ejtag_info, EJTAG_INST_FASTDATA);
+       mips_ejtag_fastdata_scan(ejtag_info, 1, &val);
+
+       unsigned num_clocks = 0;        /* like in legacy code */
+       if (ejtag_info->mode != 0)
+               num_clocks = ((uint64_t)(ejtag_info->scan_delay) * adapter_get_speed_khz() + 500000) / 1000000;
+
+       for (int i = 0; i < count; i++) {
+               jtag_add_clocks(num_clocks);
+               mips_ejtag_fastdata_scan(ejtag_info, write_t, buf++);
+       }
+
+       retval = jtag_execute_queue();
+       if (retval != ERROR_OK) {
+               LOG_ERROR("fastdata load failed");
+               return retval;
+       }
+
+       retval = mips32_pracc_read_ctrl_addr(ejtag_info);
+       if (retval != ERROR_OK)
+               return retval;
+
+       if (ejtag_info->pa_addr != MIPS32_PRACC_TEXT)
+               LOG_ERROR("mini program did not return to start");
+
        return retval;
 }