Added support for SPI Flash Winbond W25Q64CV
[fw/openocd] / src / flash / nor / core.c
index 8b581b0c5ad752fff5080fe65e3cc81e0e7172c0..14aa9755158a59efcfa6ffa793ac1db3b01d9b6b 100644 (file)
@@ -1,8 +1,9 @@
 /***************************************************************************
  *   Copyright (C) 2005 by Dominic Rath <Dominic.Rath@gmx.de>              *
- *   Copyright (C) 2007,2008 Øyvind Harboe <oyvind.harboe@zylin.com>       *
+ *   Copyright (C) 2007-2010 Øyvind Harboe <oyvind.harboe@zylin.com>       *
  *   Copyright (C) 2008 by Spencer Oliver <spen@spen-soft.co.uk>           *
  *   Copyright (C) 2009 Zachary T Welch <zw@superlucidity.net>             *
+ *   Copyright (C) 2010 by Antonio Borneo <borneo.antonio@gmail.com>       *
  *                                                                         *
  *   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  *
@@ -28,7 +29,6 @@
 #include <flash/nor/imp.h>
 #include <target/image.h>
 
-
 /**
  * @file
  * Upper level of NOR flash framework.
@@ -36,7 +36,7 @@
  * primarily support access from Tcl scripts or from GDB.
  */
 
-struct flash_bank *flash_banks;
+static struct flash_bank *flash_banks;
 
 int flash_driver_erase(struct flash_bank *bank, int first, int last)
 {
@@ -44,9 +44,7 @@ int flash_driver_erase(struct flash_bank *bank, int first, int last)
 
        retval = bank->driver->erase(bank, first, last);
        if (retval != ERROR_OK)
-       {
-               LOG_ERROR("failed erasing sectors %d to %d (%d)", first, last, retval);
-       }
+               LOG_ERROR("failed erasing sectors %d to %d", first, last);
 
        return retval;
 }
@@ -54,105 +52,88 @@ int flash_driver_erase(struct flash_bank *bank, int first, int last)
 int flash_driver_protect(struct flash_bank *bank, int set, int first, int last)
 {
        int retval;
-       bool updated = false;
-
-       /* NOTE: "first == last" means protect just that sector */
 
        /* callers may not supply illegal parameters ... */
-       if (first < 0 || first > last || last >= bank->num_sectors)
+       if (first < 0 || first > last || last >= bank->num_sectors) {
+               LOG_ERROR("illegal sector range");
                return ERROR_FAIL;
+       }
 
        /* force "set" to 0/1 */
        set = !!set;
 
-       /*
-        * Filter out what trivial nonsense we can, so drivers don't have to.
+       /* DANGER!
         *
-        * Don't tell drivers to change to the current state...  it's needless,
-        * and reducing the amount of work to be done (potentially to nothing)
-        * speeds at least some things up.
-        */
-scan:
-       for (int i = first; i <= last; i++) {
-               struct flash_sector *sector = bank->sectors + i;
-
-               /* Only filter requests to protect the already-protected, or
-                * to unprotect the already-unprotected.  Changing from the
-                * unknown state (-1) to a known one is unwise but allowed;
-                * protection status is best checked first.
-                */
-               if (sector->is_protected != set)
-                       continue;
-
-               /* Shrink this range of sectors from the start; don't overrun
-                * the end.  Also shrink from the end; don't overun the start.
-                *
-                * REVISIT we could handle discontiguous regions by issuing
-                * more than one driver request.  How much would that matter?
-                */
-               if (i == first) {
-                       updated = true;
-                       first++;
-               } else if (i == last) {
-                       updated = true;
-                       last--;
-               }
-       }
-
-       /* updating the range affects the tests in the scan loop above; so
-        * re-scan, to make sure we didn't miss anything.
+        * We must not use any cached information about protection state!!!!
+        *
+        * There are a million things that could change the protect state:
+        *
+        * the target could have reset, power cycled, been hot plugged,
+        * the application could have run, etc.
+        *
+        * Drivers only receive valid sector range.
         */
-       if (updated) {
-               updated = false;
-               goto scan;
-       }
-
-       /* Single sector, already protected?  Nothing to do! */
-       if (first > last)
-               return ERROR_OK;
-
-
        retval = bank->driver->protect(bank, set, first, last);
        if (retval != ERROR_OK)
-       {
-               LOG_ERROR("failed setting protection for areas %d to %d (%d)", first, last, retval);
-       }
+               LOG_ERROR("failed setting protection for areas %d to %d", first, last);
 
        return retval;
 }
 
 int flash_driver_write(struct flash_bank *bank,
-               uint8_t *buffer, uint32_t offset, uint32_t count)
+       uint8_t *buffer, uint32_t offset, uint32_t count)
 {
        int retval;
 
        retval = bank->driver->write(bank, buffer, offset, count);
-       if (retval != ERROR_OK)
-       {
-               LOG_ERROR("error writing to flash at address 0x%08" PRIx32 " at offset 0x%8.8" PRIx32 " (%d)",
-                         bank->base, offset, retval);
+       if (retval != ERROR_OK) {
+               LOG_ERROR(
+                       "error writing to flash at address 0x%08" PRIx32 " at offset 0x%8.8" PRIx32,
+                       bank->base,
+                       offset);
        }
 
        return retval;
 }
 
+int flash_driver_read(struct flash_bank *bank,
+       uint8_t *buffer, uint32_t offset, uint32_t count)
+{
+       int retval;
+
+       LOG_DEBUG("call flash_driver_read()");
+
+       retval = bank->driver->read(bank, buffer, offset, count);
+       if (retval != ERROR_OK) {
+               LOG_ERROR(
+                       "error reading to flash at address 0x%08" PRIx32 " at offset 0x%8.8" PRIx32,
+                       bank->base,
+                       offset);
+       }
+
+       return retval;
+}
+
+int default_flash_read(struct flash_bank *bank,
+       uint8_t *buffer, uint32_t offset, uint32_t count)
+{
+       return target_read_buffer(bank->target, offset + bank->base, count, buffer);
+}
+
 void flash_bank_add(struct flash_bank *bank)
 {
        /* put flash bank in linked list */
        unsigned bank_num = 0;
-       if (flash_banks)
-       {
+       if (flash_banks) {
                /* find last flash bank */
                struct flash_bank *p = flash_banks;
-               while (NULL != p->next)
-               {
+               while (NULL != p->next) {
                        bank_num += 1;
                        p = p->next;
                }
                p->next = bank;
                bank_num += 1;
-       }
-       else
+       } else
                flash_banks = bank;
 
        bank->bank_number = bank_num;
@@ -168,12 +149,9 @@ struct flash_bank *get_flash_bank_by_num_noprobe(int num)
        struct flash_bank *p;
        int i = 0;
 
-       for (p = flash_banks; p; p = p->next)
-       {
+       for (p = flash_banks; p; p = p->next) {
                if (i++ == num)
-               {
                        return p;
-               }
        }
        LOG_ERROR("flash bank %d does not exist", num);
        return NULL;
@@ -184,20 +162,17 @@ int flash_get_bank_count(void)
        struct flash_bank *p;
        int i = 0;
        for (p = flash_banks; p; p = p->next)
-       {
                i++;
-       }
        return i;
 }
 
-struct flash_bank *get_flash_bank_by_name(const char *name)
+struct flash_bank *get_flash_bank_by_name_noprobe(const char *name)
 {
        unsigned requested = get_flash_name_index(name);
        unsigned found = 0;
 
        struct flash_bank *bank;
-       for (bank = flash_banks; NULL != bank; bank = bank->next)
-       {
+       for (bank = flash_banks; NULL != bank; bank = bank->next) {
                if (strcmp(bank->name, name) == 0)
                        return bank;
                if (!flash_driver_name_matches(bank->driver->name, name))
@@ -209,49 +184,76 @@ struct flash_bank *get_flash_bank_by_name(const char *name)
        return NULL;
 }
 
-struct flash_bank *get_flash_bank_by_num(int num)
+int get_flash_bank_by_name(const char *name, struct flash_bank **bank_result)
+{
+       struct flash_bank *bank;
+       int retval;
+
+       bank = get_flash_bank_by_name_noprobe(name);
+       if (bank != NULL) {
+               retval = bank->driver->auto_probe(bank);
+
+               if (retval != ERROR_OK) {
+                       LOG_ERROR("auto_probe failed");
+                       return retval;
+               }
+       }
+
+       *bank_result = bank;
+       return ERROR_OK;
+}
+
+int get_flash_bank_by_num(int num, struct flash_bank **bank)
 {
        struct flash_bank *p = get_flash_bank_by_num_noprobe(num);
        int retval;
 
        if (p == NULL)
-               return NULL;
+               return ERROR_FAIL;
 
        retval = p->driver->auto_probe(p);
 
-       if (retval != ERROR_OK)
-       {
-               LOG_ERROR("auto_probe failed %d\n", retval);
-               return NULL;
+       if (retval != ERROR_OK) {
+               LOG_ERROR("auto_probe failed");
+               return retval;
        }
-       return p;
+       *bank = p;
+       return ERROR_OK;
 }
 
-/* lookup flash bank by address */
-struct flash_bank *get_flash_bank_by_addr(struct target *target, uint32_t addr)
+/* lookup flash bank by address, bank not found is success, but
+ * result_bank is set to NULL. */
+int get_flash_bank_by_addr(struct target *target,
+       uint32_t addr,
+       bool check,
+       struct flash_bank **result_bank)
 {
        struct flash_bank *c;
 
        /* cycle through bank list */
-       for (c = flash_banks; c; c = c->next)
-       {
+       for (c = flash_banks; c; c = c->next) {
                int retval;
                retval = c->driver->auto_probe(c);
 
-               if (retval != ERROR_OK)
-               {
-                       LOG_ERROR("auto_probe failed %d\n", retval);
-                       return NULL;
+               if (retval != ERROR_OK) {
+                       LOG_ERROR("auto_probe failed");
+                       return retval;
                }
                /* check whether address belongs to this flash bank */
-               if ((addr >= c->base) && (addr <= c->base + (c->size - 1)) && target == c->target)
-                       return c;
+               if ((addr >= c->base) && (addr <= c->base + (c->size - 1)) && target == c->target) {
+                       *result_bank = c;
+                       return ERROR_OK;
+               }
        }
-       LOG_ERROR("No flash at address 0x%08" PRIx32 "\n", addr);
-       return NULL;
+       *result_bank = NULL;
+       if (check) {
+               LOG_ERROR("No flash at address 0x%08" PRIx32, addr);
+               return ERROR_FAIL;
+       }
+       return ERROR_OK;
 }
 
-int default_flash_mem_blank_check(struct flash_bank *bank)
+static int default_flash_mem_blank_check(struct flash_bank *bank)
 {
        struct target *target = bank->target;
        const int buffer_size = 1024;
@@ -259,38 +261,33 @@ int default_flash_mem_blank_check(struct flash_bank *bank)
        uint32_t nBytes;
        int retval = ERROR_OK;
 
-       if (bank->target->state != TARGET_HALTED)
-       {
+       if (bank->target->state != TARGET_HALTED) {
                LOG_ERROR("Target not halted");
                return ERROR_TARGET_NOT_HALTED;
        }
 
        uint8_t *buffer = malloc(buffer_size);
 
-       for (i = 0; i < bank->num_sectors; i++)
-       {
+       for (i = 0; i < bank->num_sectors; i++) {
                uint32_t j;
                bank->sectors[i].is_erased = 1;
 
-               for (j = 0; j < bank->sectors[i].size; j += buffer_size)
-               {
+               for (j = 0; j < bank->sectors[i].size; j += buffer_size) {
                        uint32_t chunk;
                        chunk = buffer_size;
                        if (chunk > (j - bank->sectors[i].size))
-                       {
                                chunk = (j - bank->sectors[i].size);
-                       }
 
-                       retval = target_read_memory(target, bank->base + bank->sectors[i].offset + j, 4, chunk/4, buffer);
+                       retval = target_read_memory(target,
+                                       bank->base + bank->sectors[i].offset + j,
+                                       4,
+                                       chunk/4,
+                                       buffer);
                        if (retval != ERROR_OK)
-                       {
                                goto done;
-                       }
 
-                       for (nBytes = 0; nBytes < chunk; nBytes++)
-                       {
-                               if (buffer[nBytes] != 0xFF)
-                               {
+                       for (nBytes = 0; nBytes < chunk; nBytes++) {
+                               if (buffer[nBytes] != 0xFF) {
                                        bank->sectors[i].is_erased = 0;
                                        break;
                                }
@@ -298,7 +295,7 @@ int default_flash_mem_blank_check(struct flash_bank *bank)
                }
        }
 
-       done:
+done:
        free(buffer);
 
        return retval;
@@ -312,19 +309,17 @@ int default_flash_blank_check(struct flash_bank *bank)
        int fast_check = 0;
        uint32_t blank;
 
-       if (bank->target->state != TARGET_HALTED)
-       {
+       if (bank->target->state != TARGET_HALTED) {
                LOG_ERROR("Target not halted");
                return ERROR_TARGET_NOT_HALTED;
        }
 
-       for (i = 0; i < bank->num_sectors; i++)
-       {
+       for (i = 0; i < bank->num_sectors; i++) {
                uint32_t address = bank->base + bank->sectors[i].offset;
                uint32_t size = bank->sectors[i].size;
 
-               if ((retval = target_blank_check_memory(target, address, size, &blank)) != ERROR_OK)
-               {
+               retval = target_blank_check_memory(target, address, size, &blank);
+               if (retval != ERROR_OK) {
                        fast_check = 0;
                        break;
                }
@@ -335,8 +330,7 @@ int default_flash_blank_check(struct flash_bank *bank)
                fast_check = 1;
        }
 
-       if (!fast_check)
-       {
+       if (!fast_check) {
                LOG_USER("Running slow fallback erase check - add working memory");
                return default_flash_mem_blank_check(bank);
        }
@@ -358,9 +352,9 @@ int default_flash_blank_check(struct flash_bank *bank)
  * sectors will be added to the range, and that reason string is used when
  * warning about those additions.
  */
-static int flash_iterate_address_range(struct target *target,
-               char *pad_reason, uint32_t addr, uint32_t length,
-               int (*callback)(struct flash_bank *bank, int first, int last))
+static int flash_iterate_address_range_inner(struct target *target,
+       char *pad_reason, uint32_t addr, uint32_t length,
+       int (*callback)(struct flash_bank *bank, int first, int last))
 {
        struct flash_bank *c;
        uint32_t last_addr = addr + length;     /* first address AFTER end */
@@ -368,20 +362,18 @@ static int flash_iterate_address_range(struct target *target,
        int last = -1;
        int i;
 
-       if ((c = get_flash_bank_by_addr(target, addr)) == NULL)
-               return ERROR_FLASH_DST_OUT_OF_BANK; /* no corresponding bank found */
+       int retval = get_flash_bank_by_addr(target, addr, true, &c);
+       if (retval != ERROR_OK)
+               return retval;
 
-       if (c->size == 0 || c->num_sectors == 0)
-       {
+       if (c->size == 0 || c->num_sectors == 0) {
                LOG_ERROR("Bank is invalid");
                return ERROR_FLASH_BANK_INVALID;
        }
 
-       if (length == 0)
-       {
+       if (length == 0) {
                /* special case, erase whole bank when length is zero */
-               if (addr != c->base)
-               {
+               if (addr != c->base) {
                        LOG_ERROR("Whole bank access must start at beginning of bank.");
                        return ERROR_FLASH_DST_BREAKS_ALIGNMENT;
                }
@@ -390,8 +382,7 @@ static int flash_iterate_address_range(struct target *target,
        }
 
        /* check whether it all fits in this bank */
-       if (addr + length - 1 > c->base + c->size - 1)
-       {
+       if (addr + length - 1 > c->base + c->size - 1) {
                LOG_ERROR("Flash access does not fit into bank.");
                return ERROR_FLASH_DST_BREAKS_ALIGNMENT;
        }
@@ -401,8 +392,7 @@ static int flash_iterate_address_range(struct target *target,
        addr -= c->base;
        last_addr -= c->base;
 
-       for (i = 0; i < c->num_sectors; i++)
-       {
+       for (i = 0; i < c->num_sectors; i++) {
                struct flash_sector *f = c->sectors + i;
                uint32_t end = f->offset + f->size;
 
@@ -426,7 +416,7 @@ static int flash_iterate_address_range(struct target *target,
                        else if (addr < end && pad_reason) {
                                /* FIXME say how many bytes (e.g. 80 KB) */
                                LOG_WARNING("Adding extra %s range, "
-                                               "%#8.8x to %#8.8x",
+                                       "%#8.8x to %#8.8x",
                                        pad_reason,
                                        (unsigned) f->offset,
                                        (unsigned) addr - 1);
@@ -447,7 +437,7 @@ static int flash_iterate_address_range(struct target *target,
                if (last_addr < end && pad_reason) {
                        /* FIXME say how many bytes (e.g. 80 KB) */
                        LOG_WARNING("Adding extra %s range, "
-                                       "%#8.8x to %#8.8x",
+                               "%#8.8x to %#8.8x",
                                pad_reason,
                                (unsigned) last_addr,
                                (unsigned) end - 1);
@@ -463,9 +453,9 @@ static int flash_iterate_address_range(struct target *target,
        /* invalid start or end address? */
        if (first == -1 || last == -1) {
                LOG_ERROR("address range 0x%8.8x .. 0x%8.8x "
-                               "is not sector-aligned",
-                               (unsigned) (c->base + addr),
-                               (unsigned) (c->base + last_addr - 1));
+                       "is not sector-aligned",
+                       (unsigned) (c->base + addr),
+                       (unsigned) (c->base + last_addr - 1));
                return ERROR_FLASH_DST_BREAKS_ALIGNMENT;
        }
 
@@ -476,11 +466,46 @@ static int flash_iterate_address_range(struct target *target,
        return callback(c, first, last);
 }
 
+/* The inner fn only handles a single bank, we could be spanning
+ * multiple chips.
+ */
+static int flash_iterate_address_range(struct target *target,
+       char *pad_reason, uint32_t addr, uint32_t length,
+       int (*callback)(struct flash_bank *bank, int first, int last))
+{
+       struct flash_bank *c;
+       int retval = ERROR_OK;
+
+       /* Danger! zero-length iterations means entire bank! */
+       do {
+               retval = get_flash_bank_by_addr(target, addr, true, &c);
+               if (retval != ERROR_OK)
+                       return retval;
+
+               uint32_t cur_length = length;
+               /* check whether it all fits in this bank */
+               if (addr + length - 1 > c->base + c->size - 1) {
+                       LOG_DEBUG("iterating over more than one flash bank.");
+                       cur_length = c->base + c->size - addr;
+               }
+               retval = flash_iterate_address_range_inner(target,
+                               pad_reason, addr, cur_length,
+                               callback);
+               if (retval != ERROR_OK)
+                       break;
+
+               length -= cur_length;
+               addr += cur_length;
+       } while (length > 0);
+
+       return retval;
+}
+
 int flash_erase_address_range(struct target *target,
-               bool pad, uint32_t addr, uint32_t length)
+       bool pad, uint32_t addr, uint32_t length)
 {
        return flash_iterate_address_range(target, pad ? "erase" : NULL,
-                       addr, length, &flash_driver_erase);
+               addr, length, &flash_driver_erase);
 }
 
 static int flash_driver_unprotect(struct flash_bank *bank, int first, int last)
@@ -488,18 +513,32 @@ static int flash_driver_unprotect(struct flash_bank *bank, int first, int last)
        return flash_driver_protect(bank, 0, first, last);
 }
 
-static int flash_unlock_address_range(struct target *target, uint32_t addr, uint32_t length)
+int flash_unlock_address_range(struct target *target, uint32_t addr, uint32_t length)
 {
        /* By default, pad to sector boundaries ... the real issue here
         * is that our (only) caller *permanently* removes protection,
         * and doesn't restore it.
         */
        return flash_iterate_address_range(target, "unprotect",
-                       addr, length, &flash_driver_unprotect);
+               addr, length, &flash_driver_unprotect);
+}
+
+static int compare_section(const void *a, const void *b)
+{
+       struct imagesection *b1, *b2;
+       b1 = *((struct imagesection **)a);
+       b2 = *((struct imagesection **)b);
+
+       if (b1->base_address == b2->base_address)
+               return 0;
+       else if (b1->base_address > b2->base_address)
+               return 1;
+       else
+               return -1;
 }
 
 int flash_write_unlock(struct target *target, struct image *image,
-               uint32_t *written, int erase, bool unlock)
+       uint32_t *written, int erase, bool unlock)
 {
        int retval = ERROR_OK;
 
@@ -508,20 +547,13 @@ int flash_write_unlock(struct target *target, struct image *image,
        struct flash_bank *c;
        int *padding;
 
-       /* REVISIT do_pad should perhaps just be another parameter.
-        * GDB wouldn't ever need it, since it erases separately.
-        * But "flash write_image" commands might want that option.
-        */
-       bool do_pad = false;
-
        section = 0;
        section_offset = 0;
 
        if (written)
                *written = 0;
 
-       if (erase)
-       {
+       if (erase) {
                /* assume all sectors need erasing - stops any problems
                 * when flash_write is called multiple times */
 
@@ -531,19 +563,27 @@ int flash_write_unlock(struct target *target, struct image *image,
        /* allocate padding array */
        padding = calloc(image->num_sections, sizeof(*padding));
 
+       /* This fn requires all sections to be in ascending order of addresses,
+        * whereas an image can have sections out of order. */
+       struct imagesection **sections = malloc(sizeof(struct imagesection *) *
+                       image->num_sections);
+       int i;
+       for (i = 0; i < image->num_sections; i++)
+               sections[i] = &image->sections[i];
+
+       qsort(sections, image->num_sections, sizeof(struct imagesection *),
+               compare_section);
+
        /* loop until we reach end of the image */
-       while (section < image->num_sections)
-       {
+       while (section < image->num_sections) {
                uint32_t buffer_size;
                uint8_t *buffer;
-               int section_first;
                int section_last;
-               uint32_t run_address = image->sections[section].base_address + section_offset;
-               uint32_t run_size = image->sections[section].size - section_offset;
+               uint32_t run_address = sections[section]->base_address + section_offset;
+               uint32_t run_size = sections[section]->size - section_offset;
                int pad_bytes = 0;
 
-               if (image->sections[section].size ==  0)
-               {
+               if (sections[section]->size ==  0) {
                        LOG_WARNING("empty section %d", section);
                        section++;
                        section_offset = 0;
@@ -551,28 +591,25 @@ int flash_write_unlock(struct target *target, struct image *image,
                }
 
                /* find the corresponding flash bank */
-               if ((c = get_flash_bank_by_addr(target, run_address)) == NULL)
-               {
-                       section++; /* and skip it */
+               retval = get_flash_bank_by_addr(target, run_address, false, &c);
+               if (retval != ERROR_OK)
+                       goto done;
+               if (c == NULL) {
+                       LOG_WARNING("no flash bank found for address %x", run_address);
+                       section++;      /* and skip it */
                        section_offset = 0;
                        continue;
                }
 
                /* collect consecutive sections which fall into the same bank */
-               section_first = section;
                section_last = section;
                padding[section] = 0;
-               while ((run_address + run_size - 1 < c->base + c->size - 1)
-                               && (section_last + 1 < image->num_sections))
-               {
-                       if (image->sections[section_last + 1].base_address < (run_address + run_size))
-                       {
-                               LOG_DEBUG("section %d out of order "
-                                               "(surprising, but supported)",
-                                               section_last + 1);
-                               /* REVISIT this can break with autoerase ...
-                                * clobbering data after it's written.
-                                */
+               while ((run_address + run_size - 1 < c->base + c->size - 1) &&
+                               (section_last + 1 < image->num_sections)) {
+                       /* sections are sorted */
+                       assert(sections[section_last + 1]->base_address >= c->base);
+                       if (sections[section_last + 1]->base_address >= (c->base + c->size)) {
+                               /* Done with this bank */
                                break;
                        }
 
@@ -593,25 +630,25 @@ int flash_write_unlock(struct target *target, struct image *image,
                        /* if we have multiple sections within our image,
                         * flash programming could fail due to alignment issues
                         * attempt to rebuild a consecutive buffer for the flash loader */
-                       pad_bytes = (image->sections[section_last + 1].base_address) - (run_address + run_size);
-                       if ((run_address + run_size + pad_bytes) > (c->base + c->size))
-                               break;
+                       pad_bytes = (sections[section_last + 1]->base_address) - (run_address + run_size);
                        padding[section_last] = pad_bytes;
-                       run_size += image->sections[++section_last].size;
+                       run_size += sections[++section_last]->size;
                        run_size += pad_bytes;
 
-                       LOG_INFO("Padding image section %d with %d bytes", section_last-1, pad_bytes);
+                       if (pad_bytes > 0)
+                               LOG_INFO("Padding image section %d with %d bytes",
+                                       section_last-1,
+                                       pad_bytes);
                }
 
-               /* fit the run into bank constraints */
-               if (run_address + run_size - 1 > c->base + c->size - 1)
-               {
-                       /* REVISIT isn't this superfluous, given the while()
-                        * loop conditions above??
+               if (run_address + run_size - 1 > c->base + c->size - 1) {
+                       /* If we have more than one flash chip back to back, then we limit
+                        * the current write operation to the current chip.
                         */
-                       LOG_WARNING("writing %d bytes only - as image section is %d bytes and bank is only %d bytes", \
-                                   (int)(c->base + c->size - run_address), (int)(run_size), (int)(c->size));
+                       LOG_DEBUG("Truncate flash run size to the current flash chip.");
+
                        run_size = c->base + c->size - run_address;
+                       assert(run_size > 0);
                }
 
                /* If we're applying any sector automagic, then pad this
@@ -625,7 +662,7 @@ int flash_write_unlock(struct target *target, struct image *image,
 
                        for (sector = 0; sector < c->num_sectors; sector++) {
                                end = c->sectors[sector].offset
-                                               + c->sectors[sector].size;
+                                       + c->sectors[sector].size;
                                if (offset_end <= end)
                                        break;
                        }
@@ -637,34 +674,48 @@ int flash_write_unlock(struct target *target, struct image *image,
 
                /* allocate buffer */
                buffer = malloc(run_size);
+               if (buffer == NULL) {
+                       LOG_ERROR("Out of memory for flash bank buffer");
+                       retval = ERROR_FAIL;
+                       goto done;
+               }
                buffer_size = 0;
 
                /* read sections to the buffer */
-               while (buffer_size < run_size)
-               {
+               while (buffer_size < run_size) {
                        size_t size_read;
 
                        size_read = run_size - buffer_size;
-                       if (size_read > image->sections[section].size - section_offset)
-                           size_read = image->sections[section].size - section_offset;
+                       if (size_read > sections[section]->size - section_offset)
+                               size_read = sections[section]->size - section_offset;
 
-                       if ((retval = image_read_section(image, section, section_offset,
-                                       size_read, buffer + buffer_size, &size_read)) != ERROR_OK || size_read == 0)
-                       {
+                       /* KLUDGE!
+                        *
+                        * #¤%#"%¤% we have to figure out the section # from the sorted
+                        * list of pointers to sections to invoke image_read_section()...
+                        */
+                       intptr_t diff = (intptr_t)sections[section] - (intptr_t)image->sections;
+                       int t_section_num = diff / sizeof(struct imagesection);
+
+                       LOG_DEBUG("image_read_section: section = %d, t_section_num = %d, "
+                                       "section_offset = %d, buffer_size = %d, size_read = %d",
+                               (int)section, (int)t_section_num, (int)section_offset,
+                               (int)buffer_size, (int)size_read);
+                       retval = image_read_section(image, t_section_num, section_offset,
+                                       size_read, buffer + buffer_size, &size_read);
+                       if (retval != ERROR_OK || size_read == 0) {
                                free(buffer);
-                               free(padding);
-                               return retval;
+                               goto done;
                        }
 
                        /* see if we need to pad the section */
                        while (padding[section]--)
-                                (buffer + buffer_size)[size_read++] = 0xff;
+                               (buffer + buffer_size)[size_read++] = 0xff;
 
                        buffer_size += size_read;
                        section_offset += size_read;
 
-                       if (section_offset >= image->sections[section].size)
-                       {
+                       if (section_offset >= sections[section]->size) {
                                section++;
                                section_offset = 0;
                        }
@@ -673,75 +724,40 @@ int flash_write_unlock(struct target *target, struct image *image,
                retval = ERROR_OK;
 
                if (unlock)
-               {
                        retval = flash_unlock_address_range(target, run_address, run_size);
-               }
-               if (retval == ERROR_OK)
-               {
-                       if (erase)
-                       {
+               if (retval == ERROR_OK) {
+                       if (erase) {
                                /* calculate and erase sectors */
                                retval = flash_erase_address_range(target,
-                                               do_pad, run_address, run_size);
+                                               true, run_address, run_size);
                        }
                }
 
-               if (retval == ERROR_OK)
-               {
+               if (retval == ERROR_OK) {
                        /* write flash sectors */
                        retval = flash_driver_write(c, buffer, run_address - c->base, run_size);
                }
 
                free(buffer);
 
-               if (retval != ERROR_OK)
-               {
-                       free(padding);
-                       return retval; /* abort operation */
+               if (retval != ERROR_OK) {
+                       /* abort operation */
+                       goto done;
                }
 
                if (written != NULL)
-                       *written += run_size; /* add run size to total written counter */
+                       *written += run_size;   /* add run size to total written counter */
        }
 
+done:
+       free(sections);
        free(padding);
 
        return retval;
 }
 
 int flash_write(struct target *target, struct image *image,
-               uint32_t *written, int erase)
+       uint32_t *written, int erase)
 {
        return flash_write_unlock(target, image, written, erase, false);
 }
-
-/**
- * Invalidates cached flash state which a target can change as it runs.
- *
- * @param target The target being resumed
- *
- * OpenOCD caches some flash state for brief periods.  For example, a sector
- * that is protected must be unprotected before OpenOCD tries to write it,
- * Also, a sector that's not erased must be erased before it's written.
- *
- * As a rule, OpenOCD and target firmware can both modify the flash, so when
- * a target starts running, OpenOCD needs to invalidate its cached state.
- */
-void nor_resume(struct target *target)
-{
-       struct flash_bank *bank;
-
-       for (bank = flash_banks; bank; bank = bank->next) {
-               int i;
-
-               if (bank->target != target)
-                       continue;
-
-               for (i = 0; i < bank->num_sectors; i++) {
-                       struct flash_sector *sector = bank->sectors + i;
-
-                       sector->is_erased = -1;
-                       sector->is_protected = -1;
-               }
-       }
-}