--- /dev/null
+/***************************************************************************
+ *   Copyright (C) 2009 by Duane Ellis                                     *
+ *   openocd@duaneellis.com                                                *
+ *                                                                         *
+ *   Copyright (C) 2010 by Olaf Lüke (at91sam3s* support)                  *
+ *   olaf@uni-paderborn.de                                                 *
+ *                                                                         *
+ *   Copyright (C) 2011 by Olivier Schonken, Jim Norris                    *
+ *   (at91sam3x* & at91sam4 support)*                                      *
+ *                                                                         *
+ *   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.                          *
+ *                                                                         *
+ *   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.             *
+****************************************************************************/
+
+/* Some of the the lower level code was based on code supplied by
+ * ATMEL under this copyright. */
+
+/* BEGIN ATMEL COPYRIGHT */
+/* ----------------------------------------------------------------------------
+ *         ATMEL Microcontroller Software Support
+ * ----------------------------------------------------------------------------
+ * Copyright (c) 2009, Atmel Corporation
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the disclaimer below.
+ *
+ * Atmel's name may not be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
+ * DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
+ * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+ * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ----------------------------------------------------------------------------
+ */
+/* END ATMEL COPYRIGHT */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "imp.h"
+#include <helper/time_support.h>
+
+#define REG_NAME_WIDTH  (12)
+
+/* at91sam4s series (has always one flash bank)*/
+#define FLASH_BANK_BASE_S   0x00400000
+
+#define         AT91C_EFC_FCMD_GETD                 (0x0)      /* (EFC) Get Flash Descriptor */
+#define         AT91C_EFC_FCMD_WP                   (0x1)      /* (EFC) Write Page */
+#define         AT91C_EFC_FCMD_WPL                  (0x2)      /* (EFC) Write Page and Lock */
+#define         AT91C_EFC_FCMD_EWP                  (0x3)      /* (EFC) Erase Page and Write Page */
+#define         AT91C_EFC_FCMD_EWPL                 (0x4)      /* (EFC) Erase Page and Write Page
+                                                                * then Lock */
+#define         AT91C_EFC_FCMD_EA                   (0x5)      /* (EFC) Erase All */
+/* cmd6 is not present int he at91sam4u4/2/1 data sheet table 19-2 */
+/* #define      AT91C_EFC_FCMD_EPL                  (0x6) // (EFC) Erase plane? */
+#define                        AT91C_EFC_FCMD_EPA                  (0x7)     /* (EFC) Erase pages */
+#define         AT91C_EFC_FCMD_SLB                  (0x8)      /* (EFC) Set Lock Bit */
+#define         AT91C_EFC_FCMD_CLB                  (0x9)      /* (EFC) Clear Lock Bit */
+#define         AT91C_EFC_FCMD_GLB                  (0xA)      /* (EFC) Get Lock Bit */
+#define         AT91C_EFC_FCMD_SFB                  (0xB)      /* (EFC) Set Fuse Bit */
+#define         AT91C_EFC_FCMD_CFB                  (0xC)      /* (EFC) Clear Fuse Bit */
+#define         AT91C_EFC_FCMD_GFB                  (0xD)      /* (EFC) Get Fuse Bit */
+#define         AT91C_EFC_FCMD_STUI                 (0xE)      /* (EFC) Start Read Unique ID */
+#define         AT91C_EFC_FCMD_SPUI                 (0xF)      /* (EFC) Stop Read Unique ID */
+
+#define  offset_EFC_FMR   0
+#define  offset_EFC_FCR   4
+#define  offset_EFC_FSR   8
+#define  offset_EFC_FRR   12
+
+extern struct flash_driver at91sam4_flash;
+
+static float _tomhz(uint32_t freq_hz)
+{
+       float f;
+
+       f = ((float)(freq_hz)) / 1000000.0;
+       return f;
+}
+
+/* How the chip is configured. */
+struct sam4_cfg {
+       uint32_t unique_id[4];
+
+       uint32_t slow_freq;
+       uint32_t rc_freq;
+       uint32_t mainosc_freq;
+       uint32_t plla_freq;
+       uint32_t mclk_freq;
+       uint32_t cpu_freq;
+       uint32_t fclk_freq;
+       uint32_t pclk0_freq;
+       uint32_t pclk1_freq;
+       uint32_t pclk2_freq;
+
+
+#define SAM4_CHIPID_CIDR          (0x400E0740)
+       uint32_t CHIPID_CIDR;
+#define SAM4_CHIPID_EXID          (0x400E0744)
+       uint32_t CHIPID_EXID;
+
+#define SAM4_PMC_BASE             (0x400E0400)
+#define SAM4_PMC_SCSR             (SAM4_PMC_BASE + 0x0008)
+       uint32_t PMC_SCSR;
+#define SAM4_PMC_PCSR             (SAM4_PMC_BASE + 0x0018)
+       uint32_t PMC_PCSR;
+#define SAM4_CKGR_UCKR            (SAM4_PMC_BASE + 0x001c)
+       uint32_t CKGR_UCKR;
+#define SAM4_CKGR_MOR             (SAM4_PMC_BASE + 0x0020)
+       uint32_t CKGR_MOR;
+#define SAM4_CKGR_MCFR            (SAM4_PMC_BASE + 0x0024)
+       uint32_t CKGR_MCFR;
+#define SAM4_CKGR_PLLAR           (SAM4_PMC_BASE + 0x0028)
+       uint32_t CKGR_PLLAR;
+#define SAM4_PMC_MCKR             (SAM4_PMC_BASE + 0x0030)
+       uint32_t PMC_MCKR;
+#define SAM4_PMC_PCK0             (SAM4_PMC_BASE + 0x0040)
+       uint32_t PMC_PCK0;
+#define SAM4_PMC_PCK1             (SAM4_PMC_BASE + 0x0044)
+       uint32_t PMC_PCK1;
+#define SAM4_PMC_PCK2             (SAM4_PMC_BASE + 0x0048)
+       uint32_t PMC_PCK2;
+#define SAM4_PMC_SR               (SAM4_PMC_BASE + 0x0068)
+       uint32_t PMC_SR;
+#define SAM4_PMC_IMR              (SAM4_PMC_BASE + 0x006c)
+       uint32_t PMC_IMR;
+#define SAM4_PMC_FSMR             (SAM4_PMC_BASE + 0x0070)
+       uint32_t PMC_FSMR;
+#define SAM4_PMC_FSPR             (SAM4_PMC_BASE + 0x0074)
+       uint32_t PMC_FSPR;
+};
+
+struct sam4_bank_private {
+       int probed;
+       /* DANGER: THERE ARE DRAGONS HERE.. */
+       /* NOTE: If you add more 'ghost' pointers */
+       /* be aware that you must *manually* update */
+       /* these pointers in the function sam4_GetDetails() */
+       /* See the comment "Here there be dragons" */
+
+       /* so we can find the chip we belong to */
+       struct sam4_chip *pChip;
+       /* so we can find the orginal bank pointer */
+       struct flash_bank *pBank;
+       unsigned bank_number;
+       uint32_t controller_address;
+       uint32_t base_address;
+       uint32_t flash_wait_states;
+       bool present;
+       unsigned size_bytes;
+       unsigned nsectors;
+       unsigned sector_size;
+       unsigned page_size;
+};
+
+struct sam4_chip_details {
+       /* THERE ARE DRAGONS HERE.. */
+       /* note: If you add pointers here */
+       /* becareful about them as they */
+       /* may need to be updated inside */
+       /* the function: "sam4_GetDetails() */
+       /* which copy/overwrites the */
+       /* 'runtime' copy of this structure */
+       uint32_t chipid_cidr;
+       const char *name;
+
+       unsigned n_gpnvms;
+#define SAM4_N_NVM_BITS 3
+       unsigned gpnvm[SAM4_N_NVM_BITS];
+       unsigned total_flash_size;
+       unsigned total_sram_size;
+       unsigned n_banks;
+#define SAM4_MAX_FLASH_BANKS 2
+       /* these are "initialized" from the global const data */
+       struct sam4_bank_private bank[SAM4_MAX_FLASH_BANKS];
+};
+
+struct sam4_chip {
+       struct sam4_chip *next;
+       int probed;
+
+       /* this is "initialized" from the global const structure */
+       struct sam4_chip_details details;
+       struct target *target;
+       struct sam4_cfg cfg;
+};
+
+
+struct sam4_reg_list {
+       uint32_t address;  size_t struct_offset; const char *name;
+       void (*explain_func)(struct sam4_chip *pInfo);
+};
+
+static struct sam4_chip *all_sam4_chips;
+
+static struct sam4_chip *get_current_sam4(struct command_context *cmd_ctx)
+{
+       struct target *t;
+       static struct sam4_chip *p;
+
+       t = get_current_target(cmd_ctx);
+       if (!t) {
+               command_print(cmd_ctx, "No current target?");
+               return NULL;
+       }
+
+       p = all_sam4_chips;
+       if (!p) {
+               /* this should not happen */
+               /* the command is not registered until the chip is created? */
+               command_print(cmd_ctx, "No SAM4 chips exist?");
+               return NULL;
+       }
+
+       while (p) {
+               if (p->target == t)
+                       return p;
+               p = p->next;
+       }
+       command_print(cmd_ctx, "Cannot find SAM4 chip?");
+       return NULL;
+}
+
+/*The actual sector size of the SAM4S flash memory is 65536 bytes. 16 sectors for a 1024KB device*/
+/*The lockregions are 8KB per lock reqion, with a 1024KB device having 128 lock reqions. */
+/*For the best results, nsectors are thus set to the amount of lock regions, and the sector_size*/
+/*set to the lock region size.  Page erases are used to erase 8KB sections when programming*/
+
+/* these are used to *initialize* the "pChip->details" structure. */
+static const struct sam4_chip_details all_sam4_details[] = {
+       /* Start at91sam4s* series */
+       /*atsam4s16c - LQFP100/BGA100*/
+       {
+               .chipid_cidr    = 0x28AC0CE0,
+               .name           = "at91sam4s16c",
+               .total_flash_size     = 1024 * 1024,
+               .total_sram_size      = 128 * 1024,
+               .n_gpnvms       = 2,
+               .n_banks        = 1,
+               {
+/*             .bank[0] = {*/
+                 {
+                       .probed = 0,
+                       .pChip  = NULL,
+                       .pBank  = NULL,
+                       .bank_number = 0,
+                       .base_address = FLASH_BANK_BASE_S,
+                       .controller_address = 0x400e0a00,
+                       .flash_wait_states = 6, /* workaround silicon bug */
+                       .present = 1,
+                       .size_bytes =  1024 * 1024,
+                       .nsectors   =  128,
+                       .sector_size = 8192,
+                       .page_size   = 512,
+                 },
+/*             .bank[1] = {*/
+                 {
+                       .present = 0,
+                       .probed = 0,
+                       .bank_number = 1,
+
+                 },
+               },
+       },
+       /*atsam4s16b - LQFP64/QFN64*/
+       {
+               .chipid_cidr    = 0x289C0CE0,
+               .name           = "at91sam4s16b",
+               .total_flash_size     = 1024 * 1024,
+               .total_sram_size      = 128 * 1024,
+               .n_gpnvms       = 2,
+               .n_banks        = 1,
+               {
+/*             .bank[0] = {*/
+                 {
+                       .probed = 0,
+                       .pChip  = NULL,
+                       .pBank  = NULL,
+                       .bank_number = 0,
+                       .base_address = FLASH_BANK_BASE_S,
+                       .controller_address = 0x400e0a00,
+                       .flash_wait_states = 6, /* workaround silicon bug */
+                       .present = 1,
+                       .size_bytes =  1024 * 1024,
+                       .nsectors   =  128,
+                       .sector_size = 8192,
+                       .page_size   = 512,
+                 },
+/*             .bank[1] = {*/
+                 {
+                       .present = 0,
+                       .probed = 0,
+                       .bank_number = 1,
+
+                 },
+               },
+       },
+       /*atsam4s16a - LQFP48/QFN48*/
+       {
+               .chipid_cidr    = 0x288C0CE0,
+               .name           = "at91sam4s16a",
+               .total_flash_size     = 1024 * 1024,
+               .total_sram_size      = 128 * 1024,
+               .n_gpnvms       = 2,
+               .n_banks        = 1,
+               {
+/*             .bank[0] = {*/
+                 {
+                       .probed = 0,
+                       .pChip  = NULL,
+                       .pBank  = NULL,
+                       .bank_number = 0,
+                       .base_address = FLASH_BANK_BASE_S,
+                       .controller_address = 0x400e0a00,
+                       .flash_wait_states = 6, /* workaround silicon bug */
+                       .present = 1,
+                       .size_bytes =  1024 * 1024,
+                       .nsectors   =  128,
+                       .sector_size = 8192,
+                       .page_size   = 512,
+                 },
+/*             .bank[1] = {*/
+                 {
+                       .present = 0,
+                       .probed = 0,
+                       .bank_number = 1,
+
+                 },
+               },
+       },
+       /*atsam4s8c - LQFP100/BGA100*/
+       {
+               .chipid_cidr    = 0x28AC0AE0,
+               .name           = "at91sam4s8c",
+               .total_flash_size     = 512 * 1024,
+               .total_sram_size      = 128 * 1024,
+               .n_gpnvms       = 2,
+               .n_banks        = 1,
+               {
+/*             .bank[0] = {*/
+                 {
+                       .probed = 0,
+                       .pChip  = NULL,
+                       .pBank  = NULL,
+                       .bank_number = 0,
+                       .base_address = FLASH_BANK_BASE_S,
+                       .controller_address = 0x400e0a00,
+                       .flash_wait_states = 6, /* workaround silicon bug */
+                       .present = 1,
+                       .size_bytes =  512 * 1024,
+                       .nsectors   =  64,
+                       .sector_size = 8192,
+                       .page_size   = 512,
+                 },
+/*             .bank[1] = {*/
+                 {
+                       .present = 0,
+                       .probed = 0,
+                       .bank_number = 1,
+
+                 },
+               },
+       },
+       /*atsam4s8b - LQFP64/BGA64*/
+       {
+               .chipid_cidr    = 0x289C0AE0,
+               .name           = "at91sam4s8b",
+               .total_flash_size     = 512 * 1024,
+               .total_sram_size      = 128 * 1024,
+               .n_gpnvms       = 2,
+               .n_banks        = 1,
+               {
+/*             .bank[0] = {*/
+                 {
+                       .probed = 0,
+                       .pChip  = NULL,
+                       .pBank  = NULL,
+                       .bank_number = 0,
+                       .base_address = FLASH_BANK_BASE_S,
+                       .controller_address = 0x400e0a00,
+                       .flash_wait_states = 6, /* workaround silicon bug */
+                       .present = 1,
+                       .size_bytes =  512 * 1024,
+                       .nsectors   =  64,
+                       .sector_size = 8192,
+                       .page_size   = 512,
+                 },
+/*             .bank[1] = {*/
+                 {
+                       .present = 0,
+                       .probed = 0,
+                       .bank_number = 1,
+
+                 },
+               },
+       },
+       /*atsam4s8a - LQFP48/BGA48*/
+       {
+               .chipid_cidr    = 0x288C0AE0,
+               .name           = "at91sam4s8a",
+               .total_flash_size     = 512 * 1024,
+               .total_sram_size      = 128 * 1024,
+               .n_gpnvms       = 2,
+               .n_banks        = 1,
+               {
+/*             .bank[0] = {*/
+                 {
+                       .probed = 0,
+                       .pChip  = NULL,
+                       .pBank  = NULL,
+                       .bank_number = 0,
+                       .base_address = FLASH_BANK_BASE_S,
+                       .controller_address = 0x400e0a00,
+                       .flash_wait_states = 6, /* workaround silicon bug */
+                       .present = 1,
+                       .size_bytes =  512 * 1024,
+                       .nsectors   =  64,
+                       .sector_size = 8192,
+                       .page_size   = 512,
+                 },
+/*             .bank[1] = {*/
+                 {
+                       .present = 0,
+                       .probed = 0,
+                       .bank_number = 1,
+
+                 },
+               },
+       },
+       /* terminate */
+       {
+               .chipid_cidr    = 0,
+               .name                   = NULL,
+       }
+};
+
+/* Globals above */
+/***********************************************************************
+ **********************************************************************
+ **********************************************************************
+ **********************************************************************
+ **********************************************************************
+ **********************************************************************/
+/* *ATMEL* style code - from the SAM4 driver code */
+
+/**
+ * Get the current status of the EEFC and
+ * the value of some status bits (LOCKE, PROGE).
+ * @param pPrivate - info about the bank
+ * @param v        - result goes here
+ */
+static int EFC_GetStatus(struct sam4_bank_private *pPrivate, uint32_t *v)
+{
+       int r;
+       r = target_read_u32(pPrivate->pChip->target,
+                       pPrivate->controller_address + offset_EFC_FSR,
+                       v);
+       LOG_DEBUG("Status: 0x%08x (lockerror: %d, cmderror: %d, ready: %d)",
+               (unsigned int)(*v),
+               ((unsigned int)((*v >> 2) & 1)),
+               ((unsigned int)((*v >> 1) & 1)),
+               ((unsigned int)((*v >> 0) & 1)));
+
+       return r;
+}
+
+/**
+ * Get the result of the last executed command.
+ * @param pPrivate - info about the bank
+ * @param v        - result goes here
+ */
+static int EFC_GetResult(struct sam4_bank_private *pPrivate, uint32_t *v)
+{
+       int r;
+       uint32_t rv;
+       r = target_read_u32(pPrivate->pChip->target,
+                       pPrivate->controller_address + offset_EFC_FRR,
+                       &rv);
+       if (v)
+               *v = rv;
+       LOG_DEBUG("Result: 0x%08x", ((unsigned int)(rv)));
+       return r;
+}
+
+static int EFC_StartCommand(struct sam4_bank_private *pPrivate,
+       unsigned command, unsigned argument)
+{
+       uint32_t n, v;
+       int r;
+       int retry;
+
+       retry = 0;
+do_retry:
+
+       /* Check command & argument */
+       switch (command) {
+
+               case AT91C_EFC_FCMD_WP:
+               case AT91C_EFC_FCMD_WPL:
+               case AT91C_EFC_FCMD_EWP:
+               case AT91C_EFC_FCMD_EWPL:
+               /* case AT91C_EFC_FCMD_EPL: */
+               case AT91C_EFC_FCMD_EPA:
+               case AT91C_EFC_FCMD_SLB:
+               case AT91C_EFC_FCMD_CLB:
+                       n = (pPrivate->size_bytes / pPrivate->page_size);
+                       if (argument >= n)
+                               LOG_ERROR("*BUG*: Embedded flash has only %u pages", (unsigned)(n));
+                       break;
+
+               case AT91C_EFC_FCMD_SFB:
+               case AT91C_EFC_FCMD_CFB:
+                       if (argument >= pPrivate->pChip->details.n_gpnvms) {
+                               LOG_ERROR("*BUG*: Embedded flash has only %d GPNVMs",
+                                               pPrivate->pChip->details.n_gpnvms);
+                       }
+                       break;
+
+               case AT91C_EFC_FCMD_GETD:
+               case AT91C_EFC_FCMD_EA:
+               case AT91C_EFC_FCMD_GLB:
+               case AT91C_EFC_FCMD_GFB:
+               case AT91C_EFC_FCMD_STUI:
+               case AT91C_EFC_FCMD_SPUI:
+                       if (argument != 0)
+                               LOG_ERROR("Argument is meaningless for cmd: %d", command);
+                       break;
+               default:
+                       LOG_ERROR("Unknown command %d", command);
+                       break;
+       }
+
+       if (command == AT91C_EFC_FCMD_SPUI) {
+               /* this is a very special situation. */
+               /* Situation (1) - error/retry - see below */
+               /*      And we are being called recursively */
+               /* Situation (2) - normal, finished reading unique id */
+       } else {
+               /* it should be "ready" */
+               EFC_GetStatus(pPrivate, &v);
+               if (v & 1) {
+                       /* then it is ready */
+                       /* we go on */
+               } else {
+                       if (retry) {
+                               /* we have done this before */
+                               /* the controller is not responding. */
+                               LOG_ERROR("flash controller(%d) is not ready! Error",
+                                       pPrivate->bank_number);
+                               return ERROR_FAIL;
+                       } else {
+                               retry++;
+                               LOG_ERROR("Flash controller(%d) is not ready, attempting reset",
+                                       pPrivate->bank_number);
+                               /* we do that by issuing the *STOP* command */
+                               EFC_StartCommand(pPrivate, AT91C_EFC_FCMD_SPUI, 0);
+                               /* above is recursive, and further recursion is blocked by */
+                               /* if (command == AT91C_EFC_FCMD_SPUI) above */
+                               goto do_retry;
+                       }
+               }
+       }
+
+       v = (0x5A << 24) | (argument << 8) | command;
+       LOG_DEBUG("Command: 0x%08x", ((unsigned int)(v)));
+       r = target_write_u32(pPrivate->pBank->target,
+                       pPrivate->controller_address + offset_EFC_FCR, v);
+       if (r != ERROR_OK)
+               LOG_DEBUG("Error Write failed");
+       return r;
+}
+
+/**
+ * Performs the given command and wait until its completion (or an error).
+ * @param pPrivate - info about the bank
+ * @param command  - Command to perform.
+ * @param argument - Optional command argument.
+ * @param status   - put command status bits here
+ */
+static int EFC_PerformCommand(struct sam4_bank_private *pPrivate,
+       unsigned command,
+       unsigned argument,
+       uint32_t *status)
+{
+
+       int r;
+       uint32_t v;
+       long long ms_now, ms_end;
+
+       /* default */
+       if (status)
+               *status = 0;
+
+       r = EFC_StartCommand(pPrivate, command, argument);
+       if (r != ERROR_OK)
+               return r;
+
+       ms_end = 10000 + timeval_ms();
+
+       do {
+               r = EFC_GetStatus(pPrivate, &v);
+               if (r != ERROR_OK)
+                       return r;
+               ms_now = timeval_ms();
+               if (ms_now > ms_end) {
+                       /* error */
+                       LOG_ERROR("Command timeout");
+                       return ERROR_FAIL;
+               }
+       } while ((v & 1) == 0);
+
+       /* error bits.. */
+       if (status)
+               *status = (v & 0x6);
+       return ERROR_OK;
+
+}
+
+/**
+ * Read the unique ID.
+ * @param pPrivate - info about the bank
+ * The unique ID is stored in the 'pPrivate' structure.
+ */
+static int FLASHD_ReadUniqueID(struct sam4_bank_private *pPrivate)
+{
+       int r;
+       uint32_t v;
+       int x;
+       /* assume 0 */
+       pPrivate->pChip->cfg.unique_id[0] = 0;
+       pPrivate->pChip->cfg.unique_id[1] = 0;
+       pPrivate->pChip->cfg.unique_id[2] = 0;
+       pPrivate->pChip->cfg.unique_id[3] = 0;
+
+       LOG_DEBUG("Begin");
+       r = EFC_StartCommand(pPrivate, AT91C_EFC_FCMD_STUI, 0);
+       if (r < 0)
+               return r;
+
+       for (x = 0; x < 4; x++) {
+               r = target_read_u32(pPrivate->pChip->target,
+                               pPrivate->pBank->base + (x * 4),
+                               &v);
+               if (r < 0)
+                       return r;
+               pPrivate->pChip->cfg.unique_id[x] = v;
+       }
+
+       r = EFC_PerformCommand(pPrivate, AT91C_EFC_FCMD_SPUI, 0, NULL);
+       LOG_DEBUG("End: R=%d, id = 0x%08x, 0x%08x, 0x%08x, 0x%08x",
+               r,
+               (unsigned int)(pPrivate->pChip->cfg.unique_id[0]),
+               (unsigned int)(pPrivate->pChip->cfg.unique_id[1]),
+               (unsigned int)(pPrivate->pChip->cfg.unique_id[2]),
+               (unsigned int)(pPrivate->pChip->cfg.unique_id[3]));
+       return r;
+
+}
+
+/**
+ * Erases the entire flash.
+ * @param pPrivate - the info about the bank.
+ */
+static int FLASHD_EraseEntireBank(struct sam4_bank_private *pPrivate)
+{
+       LOG_DEBUG("Here");
+       return EFC_PerformCommand(pPrivate, AT91C_EFC_FCMD_EA, 0, NULL);
+}
+
+/**
+ * Erases the entire flash.
+ * @param pPrivate - the info about the bank.
+ */
+static int FLASHD_ErasePages(struct sam4_bank_private *pPrivate,
+                                                        int firstPage,
+                                                        int numPages,
+                                                        uint32_t *status)
+{
+       LOG_DEBUG("Here");
+       uint8_t erasePages;
+       switch (numPages)       {
+               case 4:
+                       erasePages = 0x00;
+                       break;
+               case 8:
+                       erasePages = 0x01;
+                       break;
+               case 16:
+                       erasePages = 0x02;
+                       break;
+               case 32:
+                       erasePages = 0x03;
+                       break;
+               default:
+                       erasePages = 0x00;
+                       break;
+       }
+
+       return EFC_PerformCommand(pPrivate,
+               /* send Erase Page */
+               AT91C_EFC_FCMD_EPA,
+               (firstPage << 2) | erasePages,
+               status);
+}
+
+/**
+ * Gets current GPNVM state.
+ * @param pPrivate - info about the bank.
+ * @param gpnvm    -  GPNVM bit index.
+ * @param puthere  - result stored here.
+ */
+/* ------------------------------------------------------------------------------ */
+static int FLASHD_GetGPNVM(struct sam4_bank_private *pPrivate, unsigned gpnvm, unsigned *puthere)
+{
+       uint32_t v;
+       int r;
+
+       LOG_DEBUG("Here");
+       if (pPrivate->bank_number != 0) {
+               LOG_ERROR("GPNVM only works with Bank0");
+               return ERROR_FAIL;
+       }
+
+       if (gpnvm >= pPrivate->pChip->details.n_gpnvms) {
+               LOG_ERROR("Invalid GPNVM %d, max: %d, ignored",
+                       gpnvm, pPrivate->pChip->details.n_gpnvms);
+               return ERROR_FAIL;
+       }
+
+       /* Get GPNVMs status */
+       r = EFC_PerformCommand(pPrivate, AT91C_EFC_FCMD_GFB, 0, NULL);
+       if (r != ERROR_OK) {
+               LOG_ERROR("Failed");
+               return r;
+       }
+
+       r = EFC_GetResult(pPrivate, &v);
+
+       if (puthere) {
+               /* Check if GPNVM is set */
+               /* get the bit and make it a 0/1 */
+               *puthere = (v >> gpnvm) & 1;
+       }
+
+       return r;
+}
+
+/**
+ * Clears the selected GPNVM bit.
+ * @param pPrivate info about the bank
+ * @param gpnvm GPNVM index.
+ * @returns 0 if successful; otherwise returns an error code.
+ */
+static int FLASHD_ClrGPNVM(struct sam4_bank_private *pPrivate, unsigned gpnvm)
+{
+       int r;
+       unsigned v;
+
+       LOG_DEBUG("Here");
+       if (pPrivate->bank_number != 0) {
+               LOG_ERROR("GPNVM only works with Bank0");
+               return ERROR_FAIL;
+       }
+
+       if (gpnvm >= pPrivate->pChip->details.n_gpnvms) {
+               LOG_ERROR("Invalid GPNVM %d, max: %d, ignored",
+                       gpnvm, pPrivate->pChip->details.n_gpnvms);
+               return ERROR_FAIL;
+       }
+
+       r = FLASHD_GetGPNVM(pPrivate, gpnvm, &v);
+       if (r != ERROR_OK) {
+               LOG_DEBUG("Failed: %d", r);
+               return r;
+       }
+       r = EFC_PerformCommand(pPrivate, AT91C_EFC_FCMD_CFB, gpnvm, NULL);
+       LOG_DEBUG("End: %d", r);
+       return r;
+}
+
+/**
+ * Sets the selected GPNVM bit.
+ * @param pPrivate info about the bank
+ * @param gpnvm GPNVM index.
+ */
+static int FLASHD_SetGPNVM(struct sam4_bank_private *pPrivate, unsigned gpnvm)
+{
+       int r;
+       unsigned v;
+
+       if (pPrivate->bank_number != 0) {
+               LOG_ERROR("GPNVM only works with Bank0");
+               return ERROR_FAIL;
+       }
+
+       if (gpnvm >= pPrivate->pChip->details.n_gpnvms) {
+               LOG_ERROR("Invalid GPNVM %d, max: %d, ignored",
+                       gpnvm, pPrivate->pChip->details.n_gpnvms);
+               return ERROR_FAIL;
+       }
+
+       r = FLASHD_GetGPNVM(pPrivate, gpnvm, &v);
+       if (r != ERROR_OK)
+               return r;
+       if (v) {
+               /* already set */
+               r = ERROR_OK;
+       } else {
+               /* set it */
+               r = EFC_PerformCommand(pPrivate, AT91C_EFC_FCMD_SFB, gpnvm, NULL);
+       }
+       return r;
+}
+
+/**
+ * Returns a bit field (at most 64) of locked regions within a page.
+ * @param pPrivate info about the bank
+ * @param v where to store locked bits
+ */
+static int FLASHD_GetLockBits(struct sam4_bank_private *pPrivate, uint32_t *v)
+{
+       int r;
+       LOG_DEBUG("Here");
+       r = EFC_PerformCommand(pPrivate, AT91C_EFC_FCMD_GLB, 0, NULL);
+       if (r == ERROR_OK)      {
+               r = EFC_GetResult(pPrivate, v);
+               r = EFC_GetResult(pPrivate, v);
+               r = EFC_GetResult(pPrivate, v);
+               r = EFC_GetResult(pPrivate, v);
+       }
+       LOG_DEBUG("End: %d", r);
+       return r;
+}
+
+/**
+ * Unlocks all the regions in the given address range.
+ * @param pPrivate info about the bank
+ * @param start_sector first sector to unlock
+ * @param end_sector last (inclusive) to unlock
+ */
+
+static int FLASHD_Unlock(struct sam4_bank_private *pPrivate,
+       unsigned start_sector,
+       unsigned end_sector)
+{
+       int r;
+       uint32_t status;
+       uint32_t pg;
+       uint32_t pages_per_sector;
+
+       pages_per_sector = pPrivate->sector_size / pPrivate->page_size;
+
+       /* Unlock all pages */
+       while (start_sector <= end_sector) {
+               pg = start_sector * pages_per_sector;
+
+               r = EFC_PerformCommand(pPrivate, AT91C_EFC_FCMD_CLB, pg, &status);
+               if (r != ERROR_OK)
+                       return r;
+               start_sector++;
+       }
+
+       return ERROR_OK;
+}
+
+/**
+ * Locks regions
+ * @param pPrivate - info about the bank
+ * @param start_sector - first sector to lock
+ * @param end_sector   - last sector (inclusive) to lock
+ */
+static int FLASHD_Lock(struct sam4_bank_private *pPrivate,
+       unsigned start_sector,
+       unsigned end_sector)
+{
+       uint32_t status;
+       uint32_t pg;
+       uint32_t pages_per_sector;
+       int r;
+
+       pages_per_sector = pPrivate->sector_size / pPrivate->page_size;
+
+       /* Lock all pages */
+       while (start_sector <= end_sector) {
+               pg = start_sector * pages_per_sector;
+
+               r = EFC_PerformCommand(pPrivate, AT91C_EFC_FCMD_SLB, pg, &status);
+               if (r != ERROR_OK)
+                       return r;
+               start_sector++;
+       }
+       return ERROR_OK;
+}
+
+/****** END SAM4 CODE ********/
+
+/* begin helpful debug code */
+/* print the fieldname, the field value, in dec & hex, and return field value */
+static uint32_t sam4_reg_fieldname(struct sam4_chip *pChip,
+       const char *regname,
+       uint32_t value,
+       unsigned shift,
+       unsigned width)
+{
+       uint32_t v;
+       int hwidth, dwidth;
+
+
+       /* extract the field */
+       v = value >> shift;
+       v = v & ((1 << width)-1);
+       if (width <= 16) {
+               hwidth = 4;
+               dwidth = 5;
+       } else {
+               hwidth = 8;
+               dwidth = 12;
+       }
+
+       /* show the basics */
+       LOG_USER_N("\t%*s: %*d [0x%0*x] ",
+               REG_NAME_WIDTH, regname,
+               dwidth, v,
+               hwidth, v);
+       return v;
+}
+
+static const char _unknown[] = "unknown";
+static const char *const eproc_names[] = {
+       _unknown,                                       /* 0 */
+       "arm946es",                                     /* 1 */
+       "arm7tdmi",                                     /* 2 */
+       "cortex-m3",                            /* 3 */
+       "arm920t",                                      /* 4 */
+       "arm926ejs",                            /* 5 */
+       "cortex-a5",                            /* 6 */
+       "cortex-m4",                            /* 7 */
+       _unknown,                                       /* 8 */
+       _unknown,                                       /* 9 */
+       _unknown,                                       /* 10 */
+       _unknown,                                       /* 11 */
+       _unknown,                                       /* 12 */
+       _unknown,                                       /* 13 */
+       _unknown,                                       /* 14 */
+       _unknown,                                       /* 15 */
+};
+
+#define nvpsize2 nvpsize               /* these two tables are identical */
+static const char *const nvpsize[] = {
+       "none",                                         /*  0 */
+       "8K bytes",                                     /*  1 */
+       "16K bytes",                            /*  2 */
+       "32K bytes",                            /*  3 */
+       _unknown,                                       /*  4 */
+       "64K bytes",                            /*  5 */
+       _unknown,                                       /*  6 */
+       "128K bytes",                           /*  7 */
+       _unknown,                                       /*  8 */
+       "256K bytes",                           /*  9 */
+       "512K bytes",                           /* 10 */
+       _unknown,                                       /* 11 */
+       "1024K bytes",                          /* 12 */
+       _unknown,                                       /* 13 */
+       "2048K bytes",                          /* 14 */
+       _unknown,                                       /* 15 */
+};
+
+static const char *const sramsize[] = {
+       "48K Bytes",                            /*  0 */
+       "1K Bytes",                                     /*  1 */
+       "2K Bytes",                                     /*  2 */
+       "6K Bytes",                                     /*  3 */
+       "112K Bytes",                           /*  4 */
+       "4K Bytes",                                     /*  5 */
+       "80K Bytes",                            /*  6 */
+       "160K Bytes",                           /*  7 */
+       "8K Bytes",                                     /*  8 */
+       "16K Bytes",                            /*  9 */
+       "32K Bytes",                            /* 10 */
+       "64K Bytes",                            /* 11 */
+       "128K Bytes",                           /* 12 */
+       "256K Bytes",                           /* 13 */
+       "96K Bytes",                            /* 14 */
+       "512K Bytes",                           /* 15 */
+
+};
+
+static const struct archnames { unsigned value; const char *name; } archnames[] = {
+       { 0x19,  "AT91SAM9xx Series"                                            },
+       { 0x29,  "AT91SAM9XExx Series"                                          },
+       { 0x34,  "AT91x34 Series"                                                       },
+       { 0x37,  "CAP7 Series"                                                          },
+       { 0x39,  "CAP9 Series"                                                          },
+       { 0x3B,  "CAP11 Series"                                                         },
+       { 0x40,  "AT91x40 Series"                                                       },
+       { 0x42,  "AT91x42 Series"                                                       },
+       { 0x55,  "AT91x55 Series"                                                       },
+       { 0x60,  "AT91SAM7Axx Series"                                           },
+       { 0x61,  "AT91SAM7AQxx Series"                                          },
+       { 0x63,  "AT91x63 Series"                                                       },
+       { 0x70,  "AT91SAM7Sxx Series"                                           },
+       { 0x71,  "AT91SAM7XCxx Series"                                          },
+       { 0x72,  "AT91SAM7SExx Series"                                          },
+       { 0x73,  "AT91SAM7Lxx Series"                                           },
+       { 0x75,  "AT91SAM7Xxx Series"                                           },
+       { 0x76,  "AT91SAM7SLxx Series"                                          },
+       { 0x80,  "ATSAM3UxC Series (100-pin version)"           },
+       { 0x81,  "ATSAM3UxE Series (144-pin version)"           },
+       { 0x83,  "ATSAM3A/SAM4A xC Series (100-pin version)"},
+       { 0x84,  "ATSAM3X/SAM4X xC Series (100-pin version)"},
+       { 0x85,  "ATSAM3X/SAM4X xE Series (144-pin version)"},
+       { 0x86,  "ATSAM3X/SAM4X xG Series (208/217-pin version)"        },
+       { 0x88,  "ATSAM3S/SAM4S xA Series (48-pin version)"     },
+       { 0x89,  "ATSAM3S/SAM4S xB Series (64-pin version)"     },
+       { 0x8A,  "ATSAM3S/SAM4S xC Series (100-pin version)"},
+       { 0x92,  "AT91x92 Series"                                                       },
+       { 0x93,  "ATSAM3NxA Series (48-pin version)"            },
+       { 0x94,  "ATSAM3NxB Series (64-pin version)"            },
+       { 0x95,  "ATSAM3NxC Series (100-pin version)"           },
+       { 0x98,  "ATSAM3SDxA Series (48-pin version)"           },
+       { 0x99,  "ATSAM3SDxB Series (64-pin version)"           },
+       { 0x9A,  "ATSAM3SDxC Series (100-pin version)"          },
+       { 0xA5,  "ATSAM5A"                                                              },
+       { 0xF0,  "AT75Cxx Series"                                                       },
+       { -1, NULL },
+};
+
+static const char *const nvptype[] = {
+       "rom",  /* 0 */
+       "romless or onchip flash",      /* 1 */
+       "embedded flash memory",/* 2 */
+       "rom(nvpsiz) + embedded flash (nvpsiz2)",       /* 3 */
+       "sram emulating flash", /* 4 */
+       _unknown,       /* 5 */
+       _unknown,       /* 6 */
+       _unknown,       /* 7 */
+};
+
+static const char *_yes_or_no(uint32_t v)
+{
+       if (v)
+               return "YES";
+       else
+               return "NO";
+}
+
+static const char *const _rc_freq[] = {
+       "4 MHz", "8 MHz", "12 MHz", "reserved"
+};
+
+static void sam4_explain_ckgr_mor(struct sam4_chip *pChip)
+{
+       uint32_t v;
+       uint32_t rcen;
+
+       v = sam4_reg_fieldname(pChip, "MOSCXTEN", pChip->cfg.CKGR_MOR, 0, 1);
+       LOG_USER("(main xtal enabled: %s)", _yes_or_no(v));
+       v = sam4_reg_fieldname(pChip, "MOSCXTBY", pChip->cfg.CKGR_MOR, 1, 1);
+       LOG_USER("(main osc bypass: %s)", _yes_or_no(v));
+       rcen = sam4_reg_fieldname(pChip, "MOSCRCEN", pChip->cfg.CKGR_MOR, 3, 1);
+       LOG_USER("(onchip RC-OSC enabled: %s)", _yes_or_no(rcen));
+       v = sam4_reg_fieldname(pChip, "MOSCRCF", pChip->cfg.CKGR_MOR, 4, 3);
+       LOG_USER("(onchip RC-OSC freq: %s)", _rc_freq[v]);
+
+       pChip->cfg.rc_freq = 0;
+       if (rcen) {
+               switch (v) {
+                       default:
+                               pChip->cfg.rc_freq = 0;
+                               break;
+                       case 0:
+                               pChip->cfg.rc_freq = 4 * 1000 * 1000;
+                               break;
+                       case 1:
+                               pChip->cfg.rc_freq = 8 * 1000 * 1000;
+                               break;
+                       case 2:
+                               pChip->cfg.rc_freq = 12 * 1000 * 1000;
+                               break;
+               }
+       }
+
+       v = sam4_reg_fieldname(pChip, "MOSCXTST", pChip->cfg.CKGR_MOR, 8, 8);
+       LOG_USER("(startup clks, time= %f uSecs)",
+               ((float)(v * 1000000)) / ((float)(pChip->cfg.slow_freq)));
+       v = sam4_reg_fieldname(pChip, "MOSCSEL", pChip->cfg.CKGR_MOR, 24, 1);
+       LOG_USER("(mainosc source: %s)",
+               v ? "external xtal" : "internal RC");
+
+       v = sam4_reg_fieldname(pChip, "CFDEN", pChip->cfg.CKGR_MOR, 25, 1);
+       LOG_USER("(clock failure enabled: %s)",
+               _yes_or_no(v));
+}
+
+static void sam4_explain_chipid_cidr(struct sam4_chip *pChip)
+{
+       int x;
+       uint32_t v;
+       const char *cp;
+
+       sam4_reg_fieldname(pChip, "Version", pChip->cfg.CHIPID_CIDR, 0, 5);
+       LOG_USER_N("\n");
+
+       v = sam4_reg_fieldname(pChip, "EPROC", pChip->cfg.CHIPID_CIDR, 5, 3);
+       LOG_USER("%s", eproc_names[v]);
+
+       v = sam4_reg_fieldname(pChip, "NVPSIZE", pChip->cfg.CHIPID_CIDR, 8, 4);
+       LOG_USER("%s", nvpsize[v]);
+
+       v = sam4_reg_fieldname(pChip, "NVPSIZE2", pChip->cfg.CHIPID_CIDR, 12, 4);
+       LOG_USER("%s", nvpsize2[v]);
+
+       v = sam4_reg_fieldname(pChip, "SRAMSIZE", pChip->cfg.CHIPID_CIDR, 16, 4);
+       LOG_USER("%s", sramsize[v]);
+
+       v = sam4_reg_fieldname(pChip, "ARCH", pChip->cfg.CHIPID_CIDR, 20, 8);
+       cp = _unknown;
+       for (x = 0; archnames[x].name; x++) {
+               if (v == archnames[x].value) {
+                       cp = archnames[x].name;
+                       break;
+               }
+       }
+
+       LOG_USER("%s", cp);
+
+       v = sam4_reg_fieldname(pChip, "NVPTYP", pChip->cfg.CHIPID_CIDR, 28, 3);
+       LOG_USER("%s", nvptype[v]);
+
+       v = sam4_reg_fieldname(pChip, "EXTID", pChip->cfg.CHIPID_CIDR, 31, 1);
+       LOG_USER("(exists: %s)", _yes_or_no(v));
+}
+
+static void sam4_explain_ckgr_mcfr(struct sam4_chip *pChip)
+{
+       uint32_t v;
+
+       v = sam4_reg_fieldname(pChip, "MAINFRDY", pChip->cfg.CKGR_MCFR, 16, 1);
+       LOG_USER("(main ready: %s)", _yes_or_no(v));
+
+       v = sam4_reg_fieldname(pChip, "MAINF", pChip->cfg.CKGR_MCFR, 0, 16);
+
+       v = (v * pChip->cfg.slow_freq) / 16;
+       pChip->cfg.mainosc_freq = v;
+
+       LOG_USER("(%3.03f Mhz (%d.%03dkhz slowclk)",
+               _tomhz(v),
+               pChip->cfg.slow_freq / 1000,
+               pChip->cfg.slow_freq % 1000);
+}
+
+static void sam4_explain_ckgr_plla(struct sam4_chip *pChip)
+{
+       uint32_t mula, diva;
+
+       diva = sam4_reg_fieldname(pChip, "DIVA", pChip->cfg.CKGR_PLLAR, 0, 8);
+       LOG_USER_N("\n");
+       mula = sam4_reg_fieldname(pChip, "MULA", pChip->cfg.CKGR_PLLAR, 16, 11);
+       LOG_USER_N("\n");
+       pChip->cfg.plla_freq = 0;
+       if (mula == 0)
+               LOG_USER("\tPLLA Freq: (Disabled,mula = 0)");
+       else if (diva == 0)
+               LOG_USER("\tPLLA Freq: (Disabled,diva = 0)");
+       else if (diva == 1) {
+               pChip->cfg.plla_freq = (pChip->cfg.mainosc_freq * (mula + 1));
+               LOG_USER("\tPLLA Freq: %3.03f MHz",
+                       _tomhz(pChip->cfg.plla_freq));
+       }
+}
+
+static void sam4_explain_mckr(struct sam4_chip *pChip)
+{
+       uint32_t css, pres, fin = 0;
+       int pdiv = 0;
+       const char *cp = NULL;
+
+       css = sam4_reg_fieldname(pChip, "CSS", pChip->cfg.PMC_MCKR, 0, 2);
+       switch (css & 3) {
+               case 0:
+                       fin = pChip->cfg.slow_freq;
+                       cp = "slowclk";
+                       break;
+               case 1:
+                       fin = pChip->cfg.mainosc_freq;
+                       cp  = "mainosc";
+                       break;
+               case 2:
+                       fin = pChip->cfg.plla_freq;
+                       cp  = "plla";
+                       break;
+               case 3:
+                       if (pChip->cfg.CKGR_UCKR & (1 << 16)) {
+                               fin = 480 * 1000 * 1000;
+                               cp = "upll";
+                       } else {
+                               fin = 0;
+                               cp  = "upll (*ERROR* UPLL is disabled)";
+                       }
+                       break;
+               default:
+                       assert(0);
+                       break;
+       }
+
+       LOG_USER("%s (%3.03f Mhz)",
+               cp,
+               _tomhz(fin));
+       pres = sam4_reg_fieldname(pChip, "PRES", pChip->cfg.PMC_MCKR, 4, 3);
+       switch (pres & 0x07) {
+               case 0:
+                       pdiv = 1;
+                       cp = "selected clock";
+                       break;
+               case 1:
+                       pdiv = 2;
+                       cp = "clock/2";
+                       break;
+               case 2:
+                       pdiv = 4;
+                       cp = "clock/4";
+                       break;
+               case 3:
+                       pdiv = 8;
+                       cp = "clock/8";
+                       break;
+               case 4:
+                       pdiv = 16;
+                       cp = "clock/16";
+                       break;
+               case 5:
+                       pdiv = 32;
+                       cp = "clock/32";
+                       break;
+               case 6:
+                       pdiv = 64;
+                       cp = "clock/64";
+                       break;
+               case 7:
+                       pdiv = 6;
+                       cp = "clock/6";
+                       break;
+               default:
+                       assert(0);
+                       break;
+       }
+       LOG_USER("(%s)", cp);
+       fin = fin / pdiv;
+       /* sam4 has a *SINGLE* clock - */
+       /* other at91 series parts have divisors for these. */
+       pChip->cfg.cpu_freq = fin;
+       pChip->cfg.mclk_freq = fin;
+       pChip->cfg.fclk_freq = fin;
+       LOG_USER("\t\tResult CPU Freq: %3.03f",
+               _tomhz(fin));
+}
+
+#if 0
+static struct sam4_chip *target2sam4(struct target *pTarget)
+{
+       struct sam4_chip *pChip;
+
+       if (pTarget == NULL)
+               return NULL;
+
+       pChip = all_sam4_chips;
+       while (pChip) {
+               if (pChip->target == pTarget)
+                       break;  /* return below */
+               else
+                       pChip = pChip->next;
+       }
+       return pChip;
+}
+#endif
+
+static uint32_t *sam4_get_reg_ptr(struct sam4_cfg *pCfg, const struct sam4_reg_list *pList)
+{
+       /* this function exists to help */
+       /* keep funky offsetof() errors */
+       /* and casting from causing bugs */
+
+       /* By using prototypes - we can detect what would */
+       /* be casting errors. */
+
+       return (uint32_t *)(void *)(((char *)(pCfg)) + pList->struct_offset);
+}
+
+
+#define SAM4_ENTRY(NAME, FUNC)  { .address = SAM4_ ## NAME, .struct_offset = offsetof( \
+                                                 struct sam4_cfg, \
+                                                 NAME), # NAME, FUNC }
+static const struct sam4_reg_list sam4_all_regs[] = {
+       SAM4_ENTRY(CKGR_MOR, sam4_explain_ckgr_mor),
+       SAM4_ENTRY(CKGR_MCFR, sam4_explain_ckgr_mcfr),
+       SAM4_ENTRY(CKGR_PLLAR, sam4_explain_ckgr_plla),
+       SAM4_ENTRY(CKGR_UCKR, NULL),
+       SAM4_ENTRY(PMC_FSMR, NULL),
+       SAM4_ENTRY(PMC_FSPR, NULL),
+       SAM4_ENTRY(PMC_IMR, NULL),
+       SAM4_ENTRY(PMC_MCKR, sam4_explain_mckr),
+       SAM4_ENTRY(PMC_PCK0, NULL),
+       SAM4_ENTRY(PMC_PCK1, NULL),
+       SAM4_ENTRY(PMC_PCK2, NULL),
+       SAM4_ENTRY(PMC_PCSR, NULL),
+       SAM4_ENTRY(PMC_SCSR, NULL),
+       SAM4_ENTRY(PMC_SR, NULL),
+       SAM4_ENTRY(CHIPID_CIDR, sam4_explain_chipid_cidr),
+       SAM4_ENTRY(CHIPID_EXID, NULL),
+       /* TERMINATE THE LIST */
+       { .name = NULL }
+};
+#undef SAM4_ENTRY
+
+static struct sam4_bank_private *get_sam4_bank_private(struct flash_bank *bank)
+{
+       return (struct sam4_bank_private *)(bank->driver_priv);
+}
+
+/**
+ * Given a pointer to where it goes in the structure,
+ * determine the register name, address from the all registers table.
+ */
+static const struct sam4_reg_list *sam4_GetReg(struct sam4_chip *pChip, uint32_t *goes_here)
+{
+       const struct sam4_reg_list *pReg;
+
+       pReg = &(sam4_all_regs[0]);
+       while (pReg->name) {
+               uint32_t *pPossible;
+
+               /* calculate where this one go.. */
+               /* it is "possibly" this register. */
+
+               pPossible = ((uint32_t *)(void *)(((char *)(&(pChip->cfg))) + pReg->struct_offset));
+
+               /* well? Is it this register */
+               if (pPossible == goes_here) {
+                       /* Jump for joy! */
+                       return pReg;
+               }
+
+               /* next... */
+               pReg++;
+       }
+       /* This is *TOTAL*PANIC* - we are totally screwed. */
+       LOG_ERROR("INVALID SAM4 REGISTER");
+       return NULL;
+}
+
+static int sam4_ReadThisReg(struct sam4_chip *pChip, uint32_t *goes_here)
+{
+       const struct sam4_reg_list *pReg;
+       int r;
+
+       pReg = sam4_GetReg(pChip, goes_here);
+       if (!pReg)
+               return ERROR_FAIL;
+
+       r = target_read_u32(pChip->target, pReg->address, goes_here);
+       if (r != ERROR_OK) {
+               LOG_ERROR("Cannot read SAM4 register: %s @ 0x%08x, Err: %d",
+                       pReg->name, (unsigned)(pReg->address), r);
+       }
+       return r;
+}
+
+static int sam4_ReadAllRegs(struct sam4_chip *pChip)
+{
+       int r;
+       const struct sam4_reg_list *pReg;
+
+       pReg = &(sam4_all_regs[0]);
+       while (pReg->name) {
+               r = sam4_ReadThisReg(pChip,
+                               sam4_get_reg_ptr(&(pChip->cfg), pReg));
+               if (r != ERROR_OK) {
+                       LOG_ERROR("Cannot read SAM4 registere: %s @ 0x%08x, Error: %d",
+                               pReg->name, ((unsigned)(pReg->address)), r);
+                       return r;
+               }
+               pReg++;
+       }
+
+       return ERROR_OK;
+}
+
+static int sam4_GetInfo(struct sam4_chip *pChip)
+{
+       const struct sam4_reg_list *pReg;
+       uint32_t regval;
+
+       pReg = &(sam4_all_regs[0]);
+       while (pReg->name) {
+               /* display all regs */
+               LOG_DEBUG("Start: %s", pReg->name);
+               regval = *sam4_get_reg_ptr(&(pChip->cfg), pReg);
+               LOG_USER("%*s: [0x%08x] -> 0x%08x",
+                       REG_NAME_WIDTH,
+                       pReg->name,
+                       pReg->address,
+                       regval);
+               if (pReg->explain_func)
+                       (*(pReg->explain_func))(pChip);
+               LOG_DEBUG("End: %s", pReg->name);
+               pReg++;
+       }
+       LOG_USER("   rc-osc: %3.03f MHz", _tomhz(pChip->cfg.rc_freq));
+       LOG_USER("  mainosc: %3.03f MHz", _tomhz(pChip->cfg.mainosc_freq));
+       LOG_USER("     plla: %3.03f MHz", _tomhz(pChip->cfg.plla_freq));
+       LOG_USER(" cpu-freq: %3.03f MHz", _tomhz(pChip->cfg.cpu_freq));
+       LOG_USER("mclk-freq: %3.03f MHz", _tomhz(pChip->cfg.mclk_freq));
+
+       LOG_USER(" UniqueId: 0x%08x 0x%08x 0x%08x 0x%08x",
+               pChip->cfg.unique_id[0],
+               pChip->cfg.unique_id[1],
+               pChip->cfg.unique_id[2],
+               pChip->cfg.unique_id[3]);
+
+       return ERROR_OK;
+}
+
+static int sam4_protect_check(struct flash_bank *bank)
+{
+       int r;
+       uint32_t v[4] = {0};
+       unsigned x;
+       struct sam4_bank_private *pPrivate;
+
+       LOG_DEBUG("Begin");
+       if (bank->target->state != TARGET_HALTED) {
+               LOG_ERROR("Target not halted");
+               return ERROR_TARGET_NOT_HALTED;
+       }
+
+       pPrivate = get_sam4_bank_private(bank);
+       if (!pPrivate) {
+               LOG_ERROR("no private for this bank?");
+               return ERROR_FAIL;
+       }
+       if (!(pPrivate->probed))
+               return ERROR_FLASH_BANK_NOT_PROBED;
+
+       r = FLASHD_GetLockBits(pPrivate, v);
+       if (r != ERROR_OK) {
+               LOG_DEBUG("Failed: %d", r);
+               return r;
+       }
+
+       for (x = 0; x < pPrivate->nsectors; x++)
+               bank->sectors[x].is_protected = (!!(v[x >> 5] & (1 << (x % 32))));
+       LOG_DEBUG("Done");
+       return ERROR_OK;
+}
+
+FLASH_BANK_COMMAND_HANDLER(sam4_flash_bank_command)
+{
+       struct sam4_chip *pChip;
+
+       pChip = all_sam4_chips;
+
+       /* is this an existing chip? */
+       while (pChip) {
+               if (pChip->target == bank->target)
+                       break;
+               pChip = pChip->next;
+       }
+
+       if (!pChip) {
+               /* this is a *NEW* chip */
+               pChip = calloc(1, sizeof(struct sam4_chip));
+               if (!pChip) {
+                       LOG_ERROR("NO RAM!");
+                       return ERROR_FAIL;
+               }
+               pChip->target = bank->target;
+               /* insert at head */
+               pChip->next = all_sam4_chips;
+               all_sam4_chips = pChip;
+               pChip->target = bank->target;
+               /* assumption is this runs at 32khz */
+               pChip->cfg.slow_freq = 32768;
+               pChip->probed = 0;
+       }
+
+       switch (bank->base) {
+               default:
+                       LOG_ERROR("Address 0x%08x invalid bank address (try 0x%08x"
+                       "[at91sam4s series] )",
+                       ((unsigned int)(bank->base)),
+                       ((unsigned int)(FLASH_BANK_BASE_S)));
+                       return ERROR_FAIL;
+                       break;
+
+               /* at91sam4s series only has bank 0*/
+               case FLASH_BANK_BASE_S:
+                       bank->driver_priv = &(pChip->details.bank[0]);
+                       bank->bank_number = 0;
+                       pChip->details.bank[0].pChip = pChip;
+                       pChip->details.bank[0].pBank = bank;
+                       break;
+       }
+
+       /* we initialize after probing. */
+       return ERROR_OK;
+}
+
+static int sam4_GetDetails(struct sam4_bank_private *pPrivate)
+{
+       const struct sam4_chip_details *pDetails;
+       struct sam4_chip *pChip;
+       struct flash_bank *saved_banks[SAM4_MAX_FLASH_BANKS];
+       unsigned x;
+
+       LOG_DEBUG("Begin");
+       pDetails = all_sam4_details;
+       while (pDetails->name) {
+               /* Compare cidr without version bits */
+               if (pDetails->chipid_cidr == (pPrivate->pChip->cfg.CHIPID_CIDR & 0xFFFFFFE0))
+                       break;
+               else
+                       pDetails++;
+       }
+       if (pDetails->name == NULL) {
+               LOG_ERROR("SAM4 ChipID 0x%08x not found in table (perhaps you can ID this chip?)",
+                       (unsigned int)(pPrivate->pChip->cfg.CHIPID_CIDR));
+               /* Help the victim, print details about the chip */
+               LOG_INFO("SAM4 CHIPID_CIDR: 0x%08x decodes as follows",
+                       pPrivate->pChip->cfg.CHIPID_CIDR);
+               sam4_explain_chipid_cidr(pPrivate->pChip);
+               return ERROR_FAIL;
+       }
+
+       /* DANGER: THERE ARE DRAGONS HERE */
+
+       /* get our pChip - it is going */
+       /* to be over-written shortly */
+       pChip = pPrivate->pChip;
+
+       /* Note that, in reality: */
+       /*  */
+       /*     pPrivate = &(pChip->details.bank[0]) */
+       /* or  pPrivate = &(pChip->details.bank[1]) */
+       /*  */
+
+       /* save the "bank" pointers */
+       for (x = 0; x < SAM4_MAX_FLASH_BANKS; x++)
+               saved_banks[x] = pChip->details.bank[x].pBank;
+
+       /* Overwrite the "details" structure. */
+       memcpy(&(pPrivate->pChip->details),
+               pDetails,
+               sizeof(pPrivate->pChip->details));
+
+       /* now fix the ghosted pointers */
+       for (x = 0; x < SAM4_MAX_FLASH_BANKS; x++) {
+               pChip->details.bank[x].pChip = pChip;
+               pChip->details.bank[x].pBank = saved_banks[x];
+       }
+
+       /* update the *BANK*SIZE* */
+
+       LOG_DEBUG("End");
+       return ERROR_OK;
+}
+
+static int _sam4_probe(struct flash_bank *bank, int noise)
+{
+       unsigned x;
+       int r;
+       struct sam4_bank_private *pPrivate;
+
+
+       LOG_DEBUG("Begin: Bank: %d, Noise: %d", bank->bank_number, noise);
+       if (bank->target->state != TARGET_HALTED) {
+               LOG_ERROR("Target not halted");
+               return ERROR_TARGET_NOT_HALTED;
+       }
+
+       pPrivate = get_sam4_bank_private(bank);
+       if (!pPrivate) {
+               LOG_ERROR("Invalid/unknown bank number");
+               return ERROR_FAIL;
+       }
+
+       r = sam4_ReadAllRegs(pPrivate->pChip);
+       if (r != ERROR_OK)
+               return r;
+
+       LOG_DEBUG("Here");
+       if (pPrivate->pChip->probed)
+               r = sam4_GetInfo(pPrivate->pChip);
+       else
+               r = sam4_GetDetails(pPrivate);
+       if (r != ERROR_OK)
+               return r;
+
+       /* update the flash bank size */
+       for (x = 0; x < SAM4_MAX_FLASH_BANKS; x++) {
+               if (bank->base == pPrivate->pChip->details.bank[x].base_address) {
+                       bank->size = pPrivate->pChip->details.bank[x].size_bytes;
+                       break;
+               }
+       }
+
+       if (bank->sectors == NULL) {
+               bank->sectors = calloc(pPrivate->nsectors, (sizeof((bank->sectors)[0])));
+               if (bank->sectors == NULL) {
+                       LOG_ERROR("No memory!");
+                       return ERROR_FAIL;
+               }
+               bank->num_sectors = pPrivate->nsectors;
+
+               for (x = 0; ((int)(x)) < bank->num_sectors; x++) {
+                       bank->sectors[x].size = pPrivate->sector_size;
+                       bank->sectors[x].offset = x * (pPrivate->sector_size);
+                       /* mark as unknown */
+                       bank->sectors[x].is_erased = -1;
+                       bank->sectors[x].is_protected = -1;
+               }
+       }
+
+       pPrivate->probed = 1;
+
+       r = sam4_protect_check(bank);
+       if (r != ERROR_OK)
+               return r;
+
+       LOG_DEBUG("Bank = %d, nbanks = %d",
+               pPrivate->bank_number, pPrivate->pChip->details.n_banks);
+       if ((pPrivate->bank_number + 1) == pPrivate->pChip->details.n_banks) {
+               /* read unique id, */
+               /* it appears to be associated with the *last* flash bank. */
+               FLASHD_ReadUniqueID(pPrivate);
+       }
+
+       return r;
+}
+
+static int sam4_probe(struct flash_bank *bank)
+{
+       return _sam4_probe(bank, 1);
+}
+
+static int sam4_auto_probe(struct flash_bank *bank)
+{
+       return _sam4_probe(bank, 0);
+}
+
+static int sam4_erase(struct flash_bank *bank, int first, int last)
+{
+       struct sam4_bank_private *pPrivate;
+       int r;
+       int i;
+       uint32_t status;
+
+       LOG_DEBUG("Here");
+       if (bank->target->state != TARGET_HALTED) {
+               LOG_ERROR("Target not halted");
+               return ERROR_TARGET_NOT_HALTED;
+       }
+
+       r = sam4_auto_probe(bank);
+       if (r != ERROR_OK) {
+               LOG_DEBUG("Here,r=%d", r);
+               return r;
+       }
+
+       pPrivate = get_sam4_bank_private(bank);
+       if (!(pPrivate->probed))
+               return ERROR_FLASH_BANK_NOT_PROBED;
+
+       if ((first == 0) && ((last + 1) == ((int)(pPrivate->nsectors)))) {
+               /* whole chip */
+               LOG_DEBUG("Here");
+               return FLASHD_EraseEntireBank(pPrivate);
+       }
+       LOG_INFO("sam4 does not auto-erase while programing (Erasing relevant sectors)");
+       LOG_INFO("sam4 First: 0x%08x Last: 0x%08x", (unsigned int)(first), (unsigned int)(last));
+       for (i = first; i <= last; i++) {
+               /*16 pages equals 8KB - Same size as a lock region*/
+               r = FLASHD_ErasePages(pPrivate, i, 16, &status);
+               LOG_INFO("Erasing sector: 0x%08x", (unsigned int)(i));
+               if (r != ERROR_OK)
+                       LOG_ERROR("SAM4: Error performing Erase page @ lock region number %d",
+                               (unsigned int)(i));
+               if (status & (1 << 2)) {
+                       LOG_ERROR("SAM4: Lock Reqion %d is locked", (unsigned int)(i));
+                       return ERROR_FAIL;
+               }
+               if (status & (1 << 1)) {
+                       LOG_ERROR("SAM4: Flash Command error @lock region %d", (unsigned int)(i));
+                       return ERROR_FAIL;
+               }
+       }
+
+       return ERROR_OK;
+}
+
+static int sam4_protect(struct flash_bank *bank, int set, int first, int last)
+{
+       struct sam4_bank_private *pPrivate;
+       int r;
+
+       LOG_DEBUG("Here");
+       if (bank->target->state != TARGET_HALTED) {
+               LOG_ERROR("Target not halted");
+               return ERROR_TARGET_NOT_HALTED;
+       }
+
+       pPrivate = get_sam4_bank_private(bank);
+       if (!(pPrivate->probed))
+               return ERROR_FLASH_BANK_NOT_PROBED;
+
+       if (set)
+               r = FLASHD_Lock(pPrivate, (unsigned)(first), (unsigned)(last));
+       else
+               r = FLASHD_Unlock(pPrivate, (unsigned)(first), (unsigned)(last));
+       LOG_DEBUG("End: r=%d", r);
+
+       return r;
+
+}
+
+static int sam4_info(struct flash_bank *bank, char *buf, int buf_size)
+{
+       if (bank->target->state != TARGET_HALTED) {
+               LOG_ERROR("Target not halted");
+               return ERROR_TARGET_NOT_HALTED;
+       }
+       buf[0] = 0;
+       return ERROR_OK;
+}
+
+static int sam4_page_read(struct sam4_bank_private *pPrivate, unsigned pagenum, uint8_t *buf)
+{
+       uint32_t adr;
+       int r;
+
+       adr = pagenum * pPrivate->page_size;
+       adr = adr + pPrivate->base_address;
+
+       r = target_read_memory(pPrivate->pChip->target,
+                       adr,
+                       4,                                      /* THIS*MUST*BE* in 32bit values */
+                       pPrivate->page_size / 4,
+                       buf);
+       if (r != ERROR_OK)
+               LOG_ERROR("SAM4: Flash program failed to read page phys address: 0x%08x",
+                       (unsigned int)(adr));
+       return r;
+}
+
+/* The code below is basically this: */
+/* compiled with */
+/* arm-none-eabi-gcc -mthumb -mcpu = cortex-m3 -O9 -S ./foobar.c -o foobar.s */
+/*  */
+/* Only the *CPU* can write to the flash buffer. */
+/* the DAP cannot... so - we download this 28byte thing */
+/* Run the algorithm - (below) */
+/* to program the device */
+/*  */
+/* ======================================== */
+/* #include <stdint.h> */
+/*  */
+/* struct foo { */
+/*   uint32_t *dst; */
+/*   const uint32_t *src; */
+/*   int   n; */
+/*   volatile uint32_t *base; */
+/*   uint32_t   cmd; */
+/* }; */
+/*  */
+/*  */
+/* uint32_t sam4_function(struct foo *p) */
+/* { */
+/*   volatile uint32_t *v; */
+/*   uint32_t *d; */
+/*   const uint32_t *s; */
+/*   int   n; */
+/*   uint32_t r; */
+/*  */
+/*   d = p->dst; */
+/*   s = p->src; */
+/*   n = p->n; */
+/*  */
+/*   do { */
+/*     *d++ = *s++; */
+/*   } while (--n) */
+/*     ; */
+/*  */
+/*   v = p->base; */
+/*  */
+/*   v[ 1 ] = p->cmd; */
+/*   do { */
+/*     r = v[8/4]; */
+/*   } while (!(r&1)) */
+/*     ; */
+/*   return r; */
+/* } */
+/* ======================================== */
+
+static const uint8_t
+       sam4_page_write_opcodes[] = {
+       /*  24 0000 0446                mov     r4, r0 */
+       0x04, 0x46,
+       /*  25 0002 6168                ldr     r1, [r4, #4] */
+       0x61, 0x68,
+       /*  26 0004 0068                ldr     r0, [r0, #0] */
+       0x00, 0x68,
+       /*  27 0006 A268                ldr     r2, [r4, #8] */
+       0xa2, 0x68,
+       /*  28                          @ lr needed for prologue */
+       /*  29                  .L2: */
+       /*  30 0008 51F8043B            ldr     r3, [r1], #4 */
+       0x51, 0xf8, 0x04, 0x3b,
+       /*  31 000c 12F1FF32            adds    r2, r2, #-1 */
+       0x12, 0xf1, 0xff, 0x32,
+       /*  32 0010 40F8043B            str     r3, [r0], #4 */
+       0x40, 0xf8, 0x04, 0x3b,
+       /*  33 0014 F8D1                bne     .L2 */
+       0xf8, 0xd1,
+       /*  34 0016 E268                ldr     r2, [r4, #12] */
+       0xe2, 0x68,
+       /*  35 0018 2369                ldr     r3, [r4, #16] */
+       0x23, 0x69,
+       /*  36 001a 5360                str     r3, [r2, #4] */
+       0x53, 0x60,
+       /*  37 001c 0832                adds    r2, r2, #8 */
+       0x08, 0x32,
+       /*  38                  .L4: */
+       /*  39 001e 1068                ldr     r0, [r2, #0] */
+       0x10, 0x68,
+       /*  40 0020 10F0010F            tst     r0, #1 */
+       0x10, 0xf0, 0x01, 0x0f,
+       /*  41 0024 FBD0                beq     .L4 */
+       0xfb, 0xd0,
+       0x00, 0xBE                              /* bkpt #0 */
+};
+
+static int sam4_page_write(struct sam4_bank_private *pPrivate, unsigned pagenum, uint8_t *buf)
+{
+       uint32_t adr;
+       uint32_t status;
+       uint32_t fmr;   /* EEFC Flash Mode Register */
+       int r;
+
+       adr = pagenum * pPrivate->page_size;
+       adr = (adr + pPrivate->base_address);
+
+       /* Get flash mode register value */
+       r = target_read_u32(pPrivate->pChip->target, pPrivate->controller_address, &fmr);
+       if (r != ERROR_OK)
+               LOG_DEBUG("Error Read failed: read flash mode register");
+
+       /* Clear flash wait state field */
+       fmr &= 0xfffff0ff;
+
+       /* set FWS (flash wait states) field in the FMR (flash mode register) */
+       fmr |= (pPrivate->flash_wait_states << 8);
+
+       LOG_DEBUG("Flash Mode: 0x%08x", ((unsigned int)(fmr)));
+       r = target_write_u32(pPrivate->pBank->target, pPrivate->controller_address, fmr);
+       if (r != ERROR_OK)
+               LOG_DEBUG("Error Write failed: set flash mode register");
+
+       /* 1st sector 8kBytes - page 0 - 15*/
+       /* 2nd sector 8kBytes - page 16 - 30*/
+       /* 3rd sector 48kBytes - page 31 - 127*/
+       LOG_DEBUG("Wr Page %u @ phys address: 0x%08x", pagenum, (unsigned int)(adr));
+       r = target_write_memory(pPrivate->pChip->target,
+                       adr,
+                       4,                                      /* THIS*MUST*BE* in 32bit values */
+                       pPrivate->page_size / 4,
+                       buf);
+       if (r != ERROR_OK) {
+               LOG_ERROR("SAM4: Failed to write (buffer) page at phys address 0x%08x",
+                       (unsigned int)(adr));
+               return r;
+       }
+
+       r = EFC_PerformCommand(pPrivate,
+                       /* send Erase & Write Page */
+                       AT91C_EFC_FCMD_WP,      /*AT91C_EFC_FCMD_EWP only works on first two 8kb sectors*/
+                       pagenum,
+                       &status);
+
+       if (r != ERROR_OK)
+               LOG_ERROR("SAM4: Error performing Write page @ phys address 0x%08x",
+                       (unsigned int)(adr));
+       if (status & (1 << 2)) {
+               LOG_ERROR("SAM4: Page @ Phys address 0x%08x is locked", (unsigned int)(adr));
+               return ERROR_FAIL;
+       }
+       if (status & (1 << 1)) {
+               LOG_ERROR("SAM4: Flash Command error @phys address 0x%08x", (unsigned int)(adr));
+               return ERROR_FAIL;
+       }
+       return ERROR_OK;
+}
+
+static int sam4_write(struct flash_bank *bank,
+       uint8_t *buffer,
+       uint32_t offset,
+       uint32_t count)
+{
+       int n;
+       unsigned page_cur;
+       unsigned page_end;
+       int r;
+       unsigned page_offset;
+       struct sam4_bank_private *pPrivate;
+       uint8_t *pagebuffer;
+
+       /* incase we bail further below, set this to null */
+       pagebuffer = NULL;
+
+       /* ignore dumb requests */
+       if (count == 0) {
+               r = ERROR_OK;
+               goto done;
+       }
+
+       if (bank->target->state != TARGET_HALTED) {
+               LOG_ERROR("Target not halted");
+               r = ERROR_TARGET_NOT_HALTED;
+               goto done;
+       }
+
+       pPrivate = get_sam4_bank_private(bank);
+       if (!(pPrivate->probed)) {
+               r = ERROR_FLASH_BANK_NOT_PROBED;
+               goto done;
+       }
+
+       if ((offset + count) > pPrivate->size_bytes) {
+               LOG_ERROR("Flash write error - past end of bank");
+               LOG_ERROR(" offset: 0x%08x, count 0x%08x, BankEnd: 0x%08x",
+                       (unsigned int)(offset),
+                       (unsigned int)(count),
+                       (unsigned int)(pPrivate->size_bytes));
+               r = ERROR_FAIL;
+               goto done;
+       }
+
+       pagebuffer = malloc(pPrivate->page_size);
+       if (!pagebuffer) {
+               LOG_ERROR("No memory for %d Byte page buffer", (int)(pPrivate->page_size));
+               r = ERROR_FAIL;
+               goto done;
+       }
+
+       /* what page do we start & end in? */
+       page_cur = offset / pPrivate->page_size;
+       page_end = (offset + count - 1) / pPrivate->page_size;
+
+       LOG_DEBUG("Offset: 0x%08x, Count: 0x%08x", (unsigned int)(offset), (unsigned int)(count));
+       LOG_DEBUG("Page start: %d, Page End: %d", (int)(page_cur), (int)(page_end));
+
+       /* Special case: all one page */
+       /*  */
+       /* Otherwise: */
+       /*    (1) non-aligned start */
+       /*    (2) body pages */
+       /*    (3) non-aligned end. */
+
+       /* Handle special case - all one page. */
+       if (page_cur == page_end) {
+               LOG_DEBUG("Special case, all in one page");
+               r = sam4_page_read(pPrivate, page_cur, pagebuffer);
+               if (r != ERROR_OK)
+                       goto done;
+
+               page_offset = (offset & (pPrivate->page_size-1));
+               memcpy(pagebuffer + page_offset,
+                       buffer,
+                       count);
+
+               r = sam4_page_write(pPrivate, page_cur, pagebuffer);
+               if (r != ERROR_OK)
+                       goto done;
+               r = ERROR_OK;
+               goto done;
+       }
+
+       /* non-aligned start */
+       page_offset = offset & (pPrivate->page_size - 1);
+       if (page_offset) {
+               LOG_DEBUG("Not-Aligned start");
+               /* read the partial */
+               r = sam4_page_read(pPrivate, page_cur, pagebuffer);
+               if (r != ERROR_OK)
+                       goto done;
+
+               /* over-write with new data */
+               n = (pPrivate->page_size - page_offset);
+               memcpy(pagebuffer + page_offset,
+                       buffer,
+                       n);
+
+               r = sam4_page_write(pPrivate, page_cur, pagebuffer);
+               if (r != ERROR_OK)
+                       goto done;
+
+               count  -= n;
+               offset += n;
+               buffer += n;
+               page_cur++;
+       }
+
+       /* By checking that offset is correct here, we also
+       fix a clang warning */
+       assert(offset % pPrivate->page_size == 0);
+
+       /* intermediate large pages */
+       /* also - the final *terminal* */
+       /* if that terminal page is a full page */
+       LOG_DEBUG("Full Page Loop: cur=%d, end=%d, count = 0x%08x",
+               (int)page_cur, (int)page_end, (unsigned int)(count));
+
+       while ((page_cur < page_end) &&
+                       (count >= pPrivate->page_size)) {
+               r = sam4_page_write(pPrivate, page_cur, buffer);
+               if (r != ERROR_OK)
+                       goto done;
+               count -= pPrivate->page_size;
+               buffer += pPrivate->page_size;
+               page_cur += 1;
+       }
+
+       /* terminal partial page? */
+       if (count) {
+               LOG_DEBUG("Terminal partial page, count = 0x%08x", (unsigned int)(count));
+               /* we have a partial page */
+               r = sam4_page_read(pPrivate, page_cur, pagebuffer);
+               if (r != ERROR_OK)
+                       goto done;
+                                       /* data goes at start */
+               memcpy(pagebuffer, buffer, count);
+               r = sam4_page_write(pPrivate, page_cur, pagebuffer);
+               if (r != ERROR_OK)
+                       goto done;
+               buffer += count;
+       }
+       LOG_DEBUG("Done!");
+       r = ERROR_OK;
+done:
+       if (pagebuffer)
+               free(pagebuffer);
+       return r;
+}
+
+COMMAND_HANDLER(sam4_handle_info_command)
+{
+       struct sam4_chip *pChip;
+       pChip = get_current_sam4(CMD_CTX);
+       if (!pChip)
+               return ERROR_OK;
+
+       unsigned x;
+       int r;
+
+       /* bank0 must exist before we can do anything */
+       if (pChip->details.bank[0].pBank == NULL) {
+               x = 0;
+need_define:
+               command_print(CMD_CTX,
+                       "Please define bank %d via command: flash bank %s ... ",
+                       x,
+                       at91sam4_flash.name);
+               return ERROR_FAIL;
+       }
+
+       /* if bank 0 is not probed, then probe it */
+       if (!(pChip->details.bank[0].probed)) {
+               r = sam4_auto_probe(pChip->details.bank[0].pBank);
+               if (r != ERROR_OK)
+                       return ERROR_FAIL;
+       }
+       /* above guarantees the "chip details" structure is valid */
+       /* and thus, bank private areas are valid */
+       /* and we have a SAM4 chip, what a concept! */
+
+       /* auto-probe other banks, 0 done above */
+       for (x = 1; x < SAM4_MAX_FLASH_BANKS; x++) {
+               /* skip banks not present */
+               if (!(pChip->details.bank[x].present))
+                       continue;
+
+               if (pChip->details.bank[x].pBank == NULL)
+                       goto need_define;
+
+               if (pChip->details.bank[x].probed)
+                       continue;
+
+               r = sam4_auto_probe(pChip->details.bank[x].pBank);
+               if (r != ERROR_OK)
+                       return r;
+       }
+
+       r = sam4_GetInfo(pChip);
+       if (r != ERROR_OK) {
+               LOG_DEBUG("Sam4Info, Failed %d", r);
+               return r;
+       }
+
+       return ERROR_OK;
+}
+
+COMMAND_HANDLER(sam4_handle_gpnvm_command)
+{
+       unsigned x, v;
+       int r, who;
+       struct sam4_chip *pChip;
+
+       pChip = get_current_sam4(CMD_CTX);
+       if (!pChip)
+               return ERROR_OK;
+
+       if (pChip->target->state != TARGET_HALTED) {
+               LOG_ERROR("sam4 - target not halted");
+               return ERROR_TARGET_NOT_HALTED;
+       }
+
+       if (pChip->details.bank[0].pBank == NULL) {
+               command_print(CMD_CTX, "Bank0 must be defined first via: flash bank %s ...",
+                       at91sam4_flash.name);
+               return ERROR_FAIL;
+       }
+       if (!pChip->details.bank[0].probed) {
+               r = sam4_auto_probe(pChip->details.bank[0].pBank);
+               if (r != ERROR_OK)
+                       return r;
+       }
+
+       switch (CMD_ARGC) {
+               default:
+                       return ERROR_COMMAND_SYNTAX_ERROR;
+                       break;
+               case 0:
+                       goto showall;
+                       break;
+               case 1:
+                       who = -1;
+                       break;
+               case 2:
+                       if ((0 == strcmp(CMD_ARGV[0], "show")) && (0 == strcmp(CMD_ARGV[1], "all")))
+                               who = -1;
+                       else {
+                               uint32_t v32;
+                               COMMAND_PARSE_NUMBER(u32, CMD_ARGV[1], v32);
+                               who = v32;
+                       }
+                       break;
+       }
+
+       if (0 == strcmp("show", CMD_ARGV[0])) {
+               if (who == -1) {
+showall:
+                       r = ERROR_OK;
+                       for (x = 0; x < pChip->details.n_gpnvms; x++) {
+                               r = FLASHD_GetGPNVM(&(pChip->details.bank[0]), x, &v);
+                               if (r != ERROR_OK)
+                                       break;
+                               command_print(CMD_CTX, "sam4-gpnvm%u: %u", x, v);
+                       }
+                       return r;
+               }
+               if ((who >= 0) && (((unsigned)(who)) < pChip->details.n_gpnvms)) {
+                       r = FLASHD_GetGPNVM(&(pChip->details.bank[0]), who, &v);
+                       command_print(CMD_CTX, "sam4-gpnvm%u: %u", who, v);
+                       return r;
+               } else {
+                       command_print(CMD_CTX, "sam4-gpnvm invalid GPNVM: %u", who);
+                       return ERROR_COMMAND_SYNTAX_ERROR;
+               }
+       }
+
+       if (who == -1) {
+               command_print(CMD_CTX, "Missing GPNVM number");
+               return ERROR_COMMAND_SYNTAX_ERROR;
+       }
+
+       if (0 == strcmp("set", CMD_ARGV[0]))
+               r = FLASHD_SetGPNVM(&(pChip->details.bank[0]), who);
+       else if ((0 == strcmp("clr", CMD_ARGV[0])) ||
+                (0 == strcmp("clear", CMD_ARGV[0])))                   /* quietly accept both */
+               r = FLASHD_ClrGPNVM(&(pChip->details.bank[0]), who);
+       else {
+               command_print(CMD_CTX, "Unknown command: %s", CMD_ARGV[0]);
+               r = ERROR_COMMAND_SYNTAX_ERROR;
+       }
+       return r;
+}
+
+COMMAND_HANDLER(sam4_handle_slowclk_command)
+{
+       struct sam4_chip *pChip;
+
+       pChip = get_current_sam4(CMD_CTX);
+       if (!pChip)
+               return ERROR_OK;
+
+       switch (CMD_ARGC) {
+               case 0:
+                       /* show */
+                       break;
+               case 1:
+               {
+                       /* set */
+                       uint32_t v;
+                       COMMAND_PARSE_NUMBER(u32, CMD_ARGV[0], v);
+                       if (v > 200000) {
+                               /* absurd slow clock of 200Khz? */
+                               command_print(CMD_CTX, "Absurd/illegal slow clock freq: %d\n", (int)(v));
+                               return ERROR_COMMAND_SYNTAX_ERROR;
+                       }
+                       pChip->cfg.slow_freq = v;
+                       break;
+               }
+               default:
+                       /* error */
+                       command_print(CMD_CTX, "Too many parameters");
+                       return ERROR_COMMAND_SYNTAX_ERROR;
+                       break;
+       }
+       command_print(CMD_CTX, "Slowclk freq: %d.%03dkhz",
+               (int)(pChip->cfg.slow_freq / 1000),
+               (int)(pChip->cfg.slow_freq % 1000));
+       return ERROR_OK;
+}
+
+static const struct command_registration at91sam4_exec_command_handlers[] = {
+       {
+               .name = "gpnvm",
+               .handler = sam4_handle_gpnvm_command,
+               .mode = COMMAND_EXEC,
+               .usage = "[('clr'|'set'|'show') bitnum]",
+               .help = "Without arguments, shows all bits in the gpnvm "
+                       "register.  Otherwise, clears, sets, or shows one "
+                       "General Purpose Non-Volatile Memory (gpnvm) bit.",
+       },
+       {
+               .name = "info",
+               .handler = sam4_handle_info_command,
+               .mode = COMMAND_EXEC,
+               .help = "Print information about the current at91sam4 chip"
+                       "and its flash configuration.",
+       },
+       {
+               .name = "slowclk",
+               .handler = sam4_handle_slowclk_command,
+               .mode = COMMAND_EXEC,
+               .usage = "[clock_hz]",
+               .help = "Display or set the slowclock frequency "
+                       "(default 32768 Hz).",
+       },
+       COMMAND_REGISTRATION_DONE
+};
+static const struct command_registration at91sam4_command_handlers[] = {
+       {
+               .name = "at91sam4",
+               .mode = COMMAND_ANY,
+               .help = "at91sam4 flash command group",
+               .usage = "",
+               .chain = at91sam4_exec_command_handlers,
+       },
+       COMMAND_REGISTRATION_DONE
+};
+
+struct flash_driver at91sam4_flash = {
+       .name = "at91sam4",
+       .commands = at91sam4_command_handlers,
+       .flash_bank_command = sam4_flash_bank_command,
+       .erase = sam4_erase,
+       .protect = sam4_protect,
+       .write = sam4_write,
+       .read = default_flash_read,
+       .probe = sam4_probe,
+       .auto_probe = sam4_auto_probe,
+       .erase_check = default_flash_blank_check,
+       .protect_check = sam4_protect_check,
+       .info = sam4_info,
+};